river cross section: Topics by Science.gov

Sample records for river cross section

Ground beetle communities in a mountain river subjected to restoration: The Raba River, Polish Carpathians.

PubMed

Bednarska, Agnieszka J; Wyżga, Bartłomiej; Mikuś, Paweł; Kędzior, Renata

2018-01-01

Effects of passive restoration of mountain rivers on the organisms inhabiting exposed riverine sediments are considerably less understood than those concerning aquatic biota. Thus, the effects of a recovery of the Raba River after abandonment of maintenance of its channelization scheme on ground beetle (Coleoptera: Carabidae) communities were investigated by comparing 6 unmanaged cross-sections and 6 cross-sections from adjacent channelized reaches. In each cross-section, ground beetles were collected from 12 sampling sites in spring, summer, and autumn, and 8 habitat parameters characterizing the cross-sections and sampling sites were determined. Within a few years after abandonment of the Raba River channelization scheme, the width of this gravel-bed river increased up to three times and its multi-thread pattern became re-established. Consequently, unmanaged river cross-sections had significantly larger channel width and more low-flow channels and eroding cutbanks than channelized cross-sections. Moreover, sampling sites in the unmanaged cross-sections were typified by significantly steeper average surface slope and larger average distance from low-flow channels than the sites in channelized cross-sections. In total, 3992 individuals from 78 taxa were collected during the study. The ground beetle assemblages were significantly more abundant and richer in species in the unmanaged than in the channelized cross-sections but no significant differences in carabid diversity indices between the two cross-section types were recorded. Redundancy Analysis indicated active river zone width as the only variable explaining differences in abundance and species richness among the cross-sections. Multiple regression analysis indicated species diversity to predominantly depend on the degree of plant cover and substrate grain size. The study showed that increased availability of exposed sediments in the widened river reaches allowed ground beetles to increase their abundance and species richness within a few years after the onset of river restoration, but more time may be needed for development of more diverse carabid communities. Copyright © 2017 Elsevier B.V. All rights reserved.
Optimal cross-sectional sampling for river modelling with bridges: An information theory-based method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ridolfi, E.; Napolitano, F., E-mail: francesco.napolitano@uniroma1.it; Alfonso, L.

2016-06-08

The description of river topography has a crucial role in accurate one-dimensional (1D) hydraulic modelling. Specifically, cross-sectional data define the riverbed elevation, the flood-prone area, and thus, the hydraulic behavior of the river. Here, the problem of the optimal cross-sectional spacing is solved through an information theory-based concept. The optimal subset of locations is the one with the maximum information content and the minimum amount of redundancy. The original contribution is the introduction of a methodology to sample river cross sections in the presence of bridges. The approach is tested on the Grosseto River (IT) and is compared to existingmore » guidelines. The results show that the information theory-based approach can support traditional methods to estimate rivers’ cross-sectional spacing.« less
Surveying Cross Sections of the Kootenai River Between Libby Dam, Montana, and Kootenay Lake, British Columbia, Canada

USGS Publications Warehouse

Barton, Gary J.; Moran, Edward H.; Berenbrock, Charles

2004-01-01

The declining population of Kootenai River white sturgeon, which was listed as an Endangered Species in 1994, has prompted a recovery team to assess the feasibility of various habitat enhancement scenarios to reestablish white sturgeon populations. As the first phase in this assessment, the U.S. Geological Survey collected stream channel cross-section and longitudinal data during 2002—03 at about 400 locations along the Kootenai River from Libby Dam near Libby, Montana, to where the river empties into Kootenay Lake near Creston, British Columbia, Canada. Survey control stations with a horizontal and vertical accuracy of less than 0.1 foot were established using a global positioning system (GPS) prior to collection of stream channel cross-section data along the Kootenai River. A total of 245 cross sections were surveyed. Six cross sections upstream from Kootenai Falls were surveyed using a total station where the river was too shallow or dangerous to navigate by vessel. The remaining 239 cross sections were surveyed by interfacing real-time GPS equipment with an echo sounder to obtain bathymetric data and with a laser range- finder to obtain streambank data. These data were merged, straightened, ordered, and reduced in size to be useful. Spacing between these cross sections ranged from about 600 feet in the valley flat near Deep Creek and Shorty Island and near bridges to as much as several miles in other areas. These stream channel cross sections will provide information that can be used to develop hydraulic flow models of the Kootenai River from Libby Dam, Montana, to Queens Bay on Kootenay Lake in British Columbia, Canada.
Impact of a large flood on mountain river habitats, channel morphology, and valley infrastructure

NASA Astrophysics Data System (ADS)

Hajdukiewicz, Hanna; Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Radecki-Pawlik, Artur

2016-11-01

The Biała River, Polish Carpathians, was considerably modified by channelization and channel incision in the twentieth century. To restore the Biała, establishing an erodible corridor was proposed in two river sections located in its mountain and foothill course. In these sections, longer, unmanaged channel reaches alternate with short, channelized reaches; and channel narrowing and incision increases in the downstream direction. In June 2010 an 80-year flood occurred on the river; and this study aims at determining its effects on physical habitat conditions for river biota, channel morphology, and valley-floor infrastructure. Surveys of 10 pairs of closely located, unmanaged and channelized cross sections, performed in 2009 and in the late summer 2010, allowed us to assess the flood-induced changes to physical habitat conditions. A comparison of channel planforms determined before (2009) and after (2012) the flood provided information on the degree of channel widening as well as changes in the width of particular elements of the river's active zone in eight stretches of the Biała. The impact of the flood on valley-floor infrastructure was confronted with the degree of river widening in unmanaged and channelized river reaches. Before the flood, unmanaged cross sections were typified by finer bed material and greater lateral variability in depth-averaged and near-bed flow velocity than channelized cross sections. The flood tended to equalize habitat conditions in both types of river cross sections, obliterating differences (in particular physical habitat parameters) between channelized and unmanaged channel reaches. River widening mostly reflected an increase in the area of channel bars, whereas the widening of low-flow channels was less pronounced. A comparison of channel planform from 2009 and 2012 indicated that intense channel incision typical of downstream sections limited river widening by the flood. Active channel width increased by half in the unmanaged cross sections and by one-third in the channelized cross sections. However, damage to the valley-floor infrastructure was practically limited to the channelized river reaches with reinforced channel banks. This indicates incompetent management of riparian areas rather than the degree of river widening as a principal reason for the economic losses during the flood.
Modelling the flooding capacity of a Polish Carpathian river: A comparison of constrained and free channel conditions

NASA Astrophysics Data System (ADS)

Czech, Wiktoria; Radecki-Pawlik, Artur; Wyżga, Bartłomiej; Hajdukiewicz, Hanna

2016-11-01

The gravel-bed Biała River, Polish Carpathians, was heavily affected by channelization and channel incision in the twentieth century. Not only were these impacts detrimental to the ecological state of the river, but they also adversely modified the conditions of floodwater retention and flood wave passage. Therefore, a few years ago an erodible corridor was delimited in two sections of the Biała to enable restoration of the river. In these sections, short, channelized reaches located in the vicinity of bridges alternate with longer, unmanaged channel reaches, which either avoided channelization or in which the channel has widened after the channelization scheme ceased to be maintained. Effects of these alternating channel morphologies on the conditions for flood flows were investigated in a study of 10 pairs of neighbouring river cross sections with constrained and freely developed morphology. Discharges of particular recurrence intervals were determined for each cross section using an empirical formula. The morphology of the cross sections together with data about channel slope and roughness of particular parts of the cross sections were used as input data to the hydraulic modelling performed with the one-dimensional steady-flow HEC-RAS software. The results indicated that freely developed cross sections, usually with multithread morphology, are typified by significantly lower water depth but larger width and cross-sectional flow area at particular discharges than single-thread, channelized cross sections. They also exhibit significantly lower average flow velocity, unit stream power, and bed shear stress. The pattern of differences in the hydraulic parameters of flood flows apparent between the two types of river cross sections varies with the discharges of different frequency, and the contrasts in hydraulic parameters between unmanaged and channelized cross sections are most pronounced at low-frequency, high-magnitude floods. However, because of the deep incision of the river, both cross section types are typified by a similar, low potential for the retention of floodwater in floodplain areas. The study indicated that even though river restoration has only begun here, it already brings beneficial effects for flood risk management, reducing flow energy and shear forces exerted on the bed and banks of the channel in unmanaged river reaches. Only within wide, unmanaged channel reaches can the flows of low-frequency, high-magnitude floods be conveyed with relatively low shear forces exerted on the channel boundary. In contrast, in channelized reaches, flow velocity and shear forces are substantially higher, inevitably causing bank erosion and channel incision.
Sand-storage changes in the Colorado River downstream from the Paria and Little Colorado rivers, April 1994 to August 1995

USGS Publications Warehouse

Graf, Julia B.; Marlow, Jonathan E.; Rigas, Patricia D.; Jansen, Samuel M.D.

1997-01-01

Sixty-six cross sections on the Colorado River in 11-kilometer reachesdownstream from the Paria and Little Colorado Rivers were monitoredfrom June 1992 to August 1995 to provide data to evaluate the effectof releases from Glen Canyon Dam on channel-sand storage and fordevelopment of multidimensional flow and sediment-transport models.Most of the network of monumented cross sections was established andfirst measured JuneSeptember 1992. Data collected from June 1992through February 1994 were published in a previous report. Crosssections downstream from the Paria River were remeasured six timesbetween April 1994 and August 1995. Most sections downstream from theLittle Colorado River were remeasured four times in the same timeperiod. Each measurement consisted of 10 passes across the section,and data presented are the mean section and the standard deviationfrom the mean. Measured depths were converted to bed elevations usingwater-surface elevations measured or estimated for each reach. A linemarked at regular intervals was strung across the river between thesection end points and used to provide horizontal-position control. AWilcoxon rank-sum test was applied to the data, and bed-elevationdifferences between successive measurements that were statisticallysignificant at the 5-percent significance level were identified andused to compute the difference in cross-sectional area frommeasurement to measurement. Changes in sand storage computed forselected cross sections are presented. Changes in area at most of theselected cross sections during the period presented in this reportwere smaller than those measured during the period covered bythe previous report. The largest changes over the monitoring periodpresented in this report were measured at section p22 (+115 squaremeters) downstream from the Paria River and at sections lb1 (+209square meters) and lc2 (156 square meters) downstream from theLittle Colorado River. This report presents selected data from themeasurements made from April 1994 through August 1995 in graphicalform and describes the electronic form of the entire data set.
Determination of channel capacity of the Mokelumne River downstream from Camanche Dam, San Joaquin and Sacramento Counties, California

USGS Publications Warehouse

Simpson, R.G.

1972-01-01

This study evaluates the adequacy of a 39-mile reach of the Mokelumne River in San Joaquin and Sacramento Counties, California, to carry planned flood releases between Camanche Reservoir and the Bensons Ferry Bridge near Thornton. The flood releases from Camanche Reservoir are to be restricted, insofar as possible, so that the flows in the Mokelumne River will not exceed 5,000 cfs (cubic feet per second) as measured at the gaging station below Camanche Dam. Areas of inundation and computed floodwater profiles are based on channel conditions in late 1970 and on observed water-surface profiles during flood releases of about 5,000 cfs in January 1969 and January 1970. The inundated area shown on the maps (appendix A) and the water-surface elevations indicated on the cross sections (appendix G) are for the flood releases of those dates. The following conclusions are contingent on there being no levee failures during periods of high flow and no significant channel changes since the flood release of January 1970. 1. High tides in San Francisco Bay and, to a greater degree, flood stages on the Cosumnes River, cause backwater in the study reach. Severe backwater conditions occurring simultaneously with a flow of 5,000 cfs in the Mokelumne River can increase the flood stage 4 to 6 feet at Bensons Ferry Bridge (cross section 1). Backwater effects decrease in an upstream direction and are less than 0.5 foot at cross section 35, a river distance of 8.6 miles upstream from cross section 1, and 1.5 miles downstream from the Peltier Road bridge. 2. In the reach between cross sections 1 and 35, a 5,000 cfs release from Camanche Reservoir with maximum backwater effect (measured at cross section 1 at the mouth of the Cosumnes River) is confined within the natural or leveed banks except on the right bank flood plain between cross sections 12 and 19. 3. Upstream from cross section 35, there is overbank flooding at a flow of 5,000 cfs between cross sections 48 and 51, and 62 and 67.5. An increase in flow from 5,000 to 6,000 cfs will cause flooding between cross sections 43 and 47, 52 and 56, and 73 and 85. 4. A discharge of 5,000 cfs will pass through all bridge openings in the study reach except that of the Western Pacific Railroad Co. bridge at cross section 4. If large amounts of debris lodge on the railroad bridge when backwater from the Cosumnes River occurs, the debris could cause higher stages and flooding along the right bank between cross sections 5 and 12.
Low shear stress gravel-bed river

USGS Publications Warehouse

Milhous, Robert T.

1997-01-01

A low stress gravel bed river is a river where the cross-sectional average dimensionless shear stress (??*) rarely exceeds 0.047. That is the case for the Gunnison River below Delta in Western Colorado. The cross-sectional average ??* in the Gunnison River has not exceeded 0.047, except at one cross section during one year, in the 87 years of record. A ??* of 0.047 is the critical ??* in the bed-load equation considered to be most applicable to gravel/cobble bed rivers (the Meyer-Peter, Mueller equation). According to this equation, there has been no bed-material movement in the Gunnison River since 1920; in fact there has been bed-material movement and this movement is biologically important. Bed-material is moved when the ??* is 0.016 or larger. Streamflows that cause a ??* of at least 0.016 maintain the aquatic habitat in a low shear stress river.
Changes in channel geometry of six eruption-affected tributaries of the Lewis River, 1980-82, Mount St. Helens, Washington

USGS Publications Warehouse

Martinson, H.A.; Finneran, S.D.; Topinka, L.J.

1984-01-01

The May 18, 1980, eruption of Mount St. Helens generated a lateral blast, lahars and tephra deposits that altered tributary channels in the Lewis River drainage basin. In order to assess potential flood hazards, study channel adjustments, and construct a sediment budget for the perturbed drainages on the east and southeast flanks of the volcano, channel cross sections were monumented and surveyed on Pine Creek, Muddy River, and Smith Creek during September and October of 1980. Additional cross sections were monumented and surveyed on Swift Creek, Bean Creek, and Clearwater Creek during the summer of 1981. The network of 88 channel cross sections has been resurveyed annually. Selected cross sections have been surveyed more frequently, following periods of higher flow. The repetitive cross-section surveys provide measurements of bank erosion or accretion and of channel erosion or aggradation. The report presents channel cross-section profiles constructed from the survey data collected during water years 1980-82. (USGS)
Changes in cross-section geometry and channel volume in two reaches of the Kankakee River in Illinois, 1959-94

USGS Publications Warehouse

Terrio, Paul J.; Nazimek, John E.

1997-01-01

The upstream reaches of the Kankakee River in Indiana have been channelized, straightened, and ditched to facilitate agriculture; the downstream reaches of the river in Illinois have not been so altered. Concerns about the adjustments of this low-gradient river in response to these disturbances have led to studies of sedimentation along the Kankakee River in Illinois. The U.S. Geological Survey (USGS) began a study in 1992 to determine sedimentation characteristics of the Kankakee River in Illinois. As part of this study, changes in channel cross-section geometry and channel volume were determined by comparing measurements of cross-section geometry over time in two reaches of the Kankakee River. The study documents some of the adjustments of the Kankakee River to land-use changes and channelization in the upstream drainage area. The timing, magnitude, and process of adjustment are of interest in developing a better understanding of how alluvial stream systems in agricultural areas respond to disturbances in the drainage area. The data used for the study included cross-section measurements made by two State of Illinois agencies from 1959 to 1980 and measurements made by the USGS in 1994. The analyses indicated a net aggradation of about 133,600 cubic yards (yd3) of sediment in the Momence Wetlands reach, a naturally meandering reach of the river, from 1980 to 1994. Aggradation occurred at 25 cross sections in this reach, and scour occurred at 10 cross sections. All but one of the cross sections in the upstream third of the reach indicated aggradation, whereas aggradation and scour were found in the middle and downstream thirds of the reach. The magnitude of change was greatest in the middle third of the reach and was least in the downstream third of the reach. A net aggradation of approximately 298,600 yd3 of sediment was indicated for the Six-Mile Pool, a pooled reach of the river upstream from a dam, from 1978 to 1994. Approximately 182,900 yd3 of sediment accumulated from 1980 to 1994, and approximately 115,700 yd3 of sediment accumulated from 1978 to 1980. Most of the aggradation occurred in the middle third of the Six-Mile Pool reach.
Complete velocity distribution in river cross-sections measured by acoustic instruments

USGS Publications Warehouse

Cheng, R.T.; Gartner, J.W.; ,

2003-01-01

To fully understand the hydraulic properties of natural rivers, velocity distribution in the river cross-section should be studied in detail. The measurement task is not straightforward because there is not an instrument that can measure the velocity distribution covering the entire cross-section. Particularly, the velocities in regions near the free surface and in the bottom boundary layer are difficult to measure, and yet the velocity properties in these regions play the most significant role in characterizing the hydraulic properties. To further characterize river hydraulics, two acoustic instruments, namely, an acoustic Doppler current profiler (ADCP), and a "BoogieDopp" (BD) were used on fixed platforms to measure the detailed velocity profiles across the river. Typically, 20 to 25 stations were used to represent a river cross-section. At each station, water velocity profiles were measured independently and/or concurrently by an ADCP and a BD. The measured velocity properties were compared and used in computation of river discharge. In a tow-tank evaluation of a BD, it has been confirmed that BD is capable of measuring water velocity at about 11 cm below the free-surface. Therefore, the surface velocity distribution across the river was extracted from the BD velocity measurements and used to compute the river discharge. These detailed velocity profiles and the composite velocity distribution were used to assess the validity of the classic theories of velocity distributions, conventional river discharge measurement methods, and for estimates of channel bottom roughness.
Habitat use by a freshwater dolphin in the low-water season

USGS Publications Warehouse

Braulik, Gill T.; Reichert, Albert P.; Ehsan, Tahir; Khan, Samiullah; Northridge, Simon P.; Alexander, Jason S.; Garstang, Richard

2012-01-01

1. Many river dolphin populations are most vulnerable during the low-water season when habitat is limited. Indus River dolphin habitat selection in the dry season was investigated using Generalized Linear Models of dolphin distribution and abundance in relation to physical features of river geomorphology and channel geometry in cross-section. 2. Dolphins selected locations in the river with significantly greater mean depth, maximum depth, cross-sectional area, and hydraulic radius, and significantly narrower river width and a lower degree of braiding than areas where dolphins were absent. They were also recorded with higher frequency at river constrictions and at confluences. 3. Channel cross-sectional area was the most important factor affecting dolphin presence and abundance, with the area of water below 1 m in depth exerting the greatest influence. Indus dolphins avoided channels with small cross-sectional area (2), presumably owing to the risk of entrapment and reduced foraging opportunities. 4. Channel geometry had a greater ability to explain dolphin distribution than river geomorphology; however, both analyses indicated similar types of habitat selection. The dolphin–habitat relationships identified in the river geomorphology analysis were scale-dependent, indicating that dolphin distribution is driven by the occurrence of discrete small-scale features, such as confluences and constrictions, as well as by broader-scale habitat complexes. 5. There are numerous plans to impound or extract more water from the Indus River system. If low-water season flows are allowed to decrease further, the amount of deeper habitat will decline, there may be insufficient patches of suitable habitat to support the dolphin population through the low-water season, and dolphins may become isolated within deeper river sections, unable or unwilling to traverse through shallows between favourable patches of habitat.
Simulation of unsteady flow and solute transport in a tidal river network

USGS Publications Warehouse

Zhan, X.

2003-01-01

A mathematical model and numerical method for water flow and solute transport in a tidal river network is presented. The tidal river network is defined as a system of open channels of rivers with junctions and cross sections. As an example, the Pearl River in China is represented by a network of 104 channels, 62 nodes, and a total of 330 cross sections with 11 boundary section for one of the applications. The simulations are performed with a supercomputer for seven scenarios of water flow and/or solute transport in the Pearl River, China, with different hydrological and weather conditions. Comparisons with available data are shown. The intention of this study is to summarize previous works and to provide a useful tool for water environmental management in a tidal river network, particularly for the Pearl River, China.
55. CROSS SECTION OF POWER HOUSE, EXHIBIT L, SANTA ANA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

55. CROSS SECTION OF POWER HOUSE, EXHIBIT L, SANTA ANA RIVER NO. 1 PROJECT, APR. 30, 1945. SCE drawing no. 523199 (sheet no. 9, for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, SAR-1 Powerhouse, Redlands, San Bernardino County, CA
Detailed cross sections of the Eocene Green River Formation along the north and east margins of the Piceance Basin, western Colorado, using measured sections and drill hole information

USGS Publications Warehouse

Johnson, Ronald C.

2014-01-01

This report presents two detailed cross sections of the Eocene Green River Formation in the Piceance Basin, northwestern Colorado, constructed from eight detailed measured sections, fourteen core holes, and two rotary holes. The Eocene Green River Formation in the Piceance Basin contains the world’s largest known oil shale deposit with more than 1.5 billion barrels of oil in place. It was deposited in Lake Uinta, a long-lived saline lake that once covered much of the Piceance Basin and the Uinta Basin to the west. The cross sections extend across the northern and eastern margins of the Piceance Basin and are intended to aid in correlating between surface sections and the subsurface in the basin.
Constructing river stage-discharge rating curves using remotely sensed river cross-sectional inundation areas and river bathymetry

NASA Astrophysics Data System (ADS)

Pan, Feifei; Wang, Cheng; Xi, Xiaohuan

2016-09-01

Remote sensing from satellites and airborne platforms provides valuable data for monitoring and gauging river discharge. One effective approach first estimates river stage from satellite-measured inundation area based on the inundation area-river stage relationship (IARSR), and then the estimated river stage is used to compute river discharge based on the stage-discharge rating (SDR) curve. However, this approach is difficult to implement because of a lack of data for constructing the SDR curves. This study proposes a new method to construct the SDR curves using remotely sensed river cross-sectional inundation areas and river bathymetry. The proposed method was tested over a river reach between two USGS gauging stations, i.e., Kingston Mines (KM) and Copperas Creek (CC) along the Illinois River. First a polygon over each of two cross sections was defined. A complete IARSR curve was constructed inside each polygon using digital elevation model (DEM) and river bathymetric data. The constructed IARSR curves were then used to estimate 47 river water surface elevations at each cross section based on 47 river inundation areas estimated from Landsat TM images collected during 1994-2002. The estimated water surface elevations were substituted into an objective function formed by the Bernoulli equation of gradually varied open channel flow. A nonlinear global optimization scheme was applied to solve the Manning's coefficient through minimizing the objective function value. Finally the SDR curve was constructed at the KM site using the solved Manning's coefficient, channel cross sectional geometry and the Manning's equation, and employed to estimate river discharges. The root mean square error (RMSE) in the estimated river discharges against the USGS measured river discharges is 112.4 m3/s. To consider the variation of the Manning's coefficient in the vertical direction, this study also suggested a power-law function to describe the vertical decline of the Manning's coefficient with the water level from the channel bed lowest elevation to the bank-full level. The constructed SDR curve with the vertical variation of the Manning's coefficient reduced the RMSE in the estimated river discharges to 83.9 m3/s. These results indicate that the method developed and tested in this study is effective and robust, and has the potential for improving our ability of remote sensing of river discharge and providing data for water resources management, global water cycle study, and flood forecasting and prevention.
Publications - RI 2011-3B | Alaska Division of Geological & Geophysical

Science.gov Websites

structural cross sections for the Kavik River map area, Alaska Authors: Wallace, W.K., Wartes, M.A., Decker Kavik River map area, Alaska: Alaska Division of Geological & Geophysical Surveys Report of area, Alaska (144.0 M) Sheet 2 Interpretations of seismic reflection data and structural cross sections
Channel geometry and hydrologic data for six eruption-affected tributaries of the Lewis River, Mount St. Helens, Washington, water years 1983-84

USGS Publications Warehouse

Martinson, H.A.; Hammond, H.E.; Mast, W.W.; Mango, P.D.

1986-01-01

The May 18, 1980, eruption of Mount St. Helens generated a lateral blast, lahars, and tephra deposits that altered stream channels in the Lewis River drainage basin. In order to assess potential flood hazards, monitor channel adjustments, and construct a sediment budget for disturbed drainages on the east and southeast flanks of the volcano, channel cross sections were monumented and surveyed on Pine Creek, Muddy River, and Smith Creek during September and October of 1980. Additional cross sections were monumented and surveyed on Swift Creek, Bean Creek , and Clearwater Creek during 1981. This network of channel cross sections has been resurveyed annually. Selected cross sections have been surveyed more frequently, following periods of higher flow. Longitudinal stream profiles of the low-water thalweg and (or) water surfaces were surveyed periodically for selected short reaches of channel. Corresponding map views for these reaches were constructed using the survey data and aerial photographs. This report presents plots of channel cross-section profiles, longitudinal stream profiles, and channel maps constructed from survey data collected during water years 1983-84. (USGS)
Using thermochonology to validate a balanced cross section along the Karnali River, far-western Nepal

NASA Astrophysics Data System (ADS)

Battistella, C.; Robinson, D.; McQuarrie, N.; Ghoshal, S.

2017-12-01

Multiple valid balanced cross sections can be produced from mapped surface and subsurface data. By integrating low temperature thermochronologic data, we are better able to predict subsurface geometries. Existing valid balanced cross section for far western Nepal are few (Robinson et al., 2006) and do not incorporate thermochronologic data because the data did not exist. The data published along the Simikot cross section along the Karnali River since then include muscovite Ar, zircon U-Th/He and apatite fission track. We present new mapping and a new valid balanced cross section that takes into account the new field data as well as the limitations that thermochronologic data places on the kinematics of the cross section. Additional constrains include some new geomorphology data acquired since 2006 that indicate areas of increased vertical uplift, which indicate locations of buried ramps in the Main Himalayan thrust and guide the locations of Lesser Himalayan ramps in the balanced cross section. Future work will include flexural modeling, new low temperature thermochronometic data, and 2-D thermokinematic models from a sequentially forward modeled balanced cross sections in far western Nepal.
Measurements of velocity and discharge, Grand Canyon, Arizona, May 1994

USGS Publications Warehouse

Oberg, Kevin A.; Fisk, Gregory G.; ,

1995-01-01

The U.S. Geological Survey (USGS) evaluated the feasibility of utilizing an acoustic Doppler current profiler (ADCP) to collect velocity and discharge data in the Colorado River in Grand Canyon, Arizona, in May 1994. An ADCP is an instrument that can be used to measure water velocity and discharge from a moving boat. Measurements of velocity and discharge were made with an ADCP at 54 cross sections along the Colorado River between the Little Colorado River and Diamond Creek. Concurrent measurements of discharge with an ADCP and a Price-AA current meter were made at three U.S. Geological Survey streamflow-gaging stations: Colorado River above the Little Colorado River near Desert View, Colorado River near Grand Canyon, and Colorado River above Diamond Creek near Peach Springs. Discharges measured with an ADCP were within 3 percent of the rated discharge at each streamflow-gaging station. Discharges measured with the ADCP were within 4 percent of discharges measured with a Price-AA meter, except at the Colorado River above Diamond Creek. Vertical velocity profiles were measured with the ADCP from a stationary position at four cross sections along the Colorado River. Graphs of selected vertical velocity profiles collected in a cross section near National Canyon show considerable temporal variation among profile.

Measurement of stream channel habitat using sonar

USGS Publications Warehouse

Flug, Marshall; Seitz, Heather; Scott, John

1998-01-01

An efficient and low cost technique using a sonar system was evaluated for describing channel geometry and quantifying inundated area in a large river. The boat-mounted portable sonar equipment was used to record water depths and river width measurements for direct storage on a laptop computer. The field data collected from repeated traverses at a cross-section were evaluated to determine the precision of the system and field technique. Results from validation at two different sites showed average sample standard deviations (S.D.s) of 0.12 m for these complete cross-sections, with coefficient of variations of 10%. Validation using only the mid-channel river cross-section data yields an average sample S.D. of 0.05 m, with a coefficient of variation below 5%, at a stable and gauged river site using only measurements of water depths greater than 0.6 m. Accuracy of the sonar system was evaluated by comparison to traditionally surveyed transect data from a regularly gauged site. We observed an average mean squared deviation of 46.0 cm2, considering only that portion of the cross-section inundated by more than 0.6 m of water. Our procedure proved to be a reliable, accurate, safe, quick, and economic method to record river depths, discharges, bed conditions, and substratum composition necessary for stream habitat studies.
An acoustic doppler current profiler survey of flow velocities in Detroit River, a connecting channel of the Great Lakes

USGS Publications Warehouse

Holtschlag, David J.; Koschik, John A.

2003-01-01

Acoustic Doppler current profilers (ADCP) were used to survey flow velocities in Detroit River from July 8-19, 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. More than 3.5 million point velocities were measured at 130 cross sections. Cross sections were generally spaced about 1,800 ft apart along the river from the head of Detroit River at the outlet of Lake St. Clair to the mouth of Detroit River on Lake Erie. Two transects were surveyed at each cross section, one in each direction across the river. Along each transect, velocity profiles were generally obtained 0.8-2.2 ft apart. At each velocity profile, average water velocity data were obtained at 1.64 ft intervals of depth. The raw position and velocity data from the ADCP field survey were adjusted for local magnetic anomalies using global positioning system (GPS) measurements at the end points of the transects. The adjusted velocity and ancillary data can be retrieved though the internet and extracted to column-oriented data files.
On the derivation of flow rating curves in data-scarce environments

NASA Astrophysics Data System (ADS)

Manfreda, Salvatore

2018-07-01

River monitoring is a critical issue for hydrological modelling that relies strongly on the use of flow rating curves (FRCs). In most cases, these functions are derived by least-squares fitting which usually leads to good performance indices, even when based on a limited range of data that especially lack high flow observations. In this context, cross-section geometry is a controlling factor which is not fully exploited in classical approaches. In fact, river discharge is obtained as the product of two factors: 1) the area of the wetted cross-section and 2) the cross-sectionally averaged velocity. Both factors can be expressed as a function of the river stage, defining a viable alternative in the derivation of FRCs. This makes it possible to exploit information about cross-section geometry limiting, at least partially, the uncertainty in the extrapolation of discharge at higher flow values. Numerical analyses and field data confirm the reliability of the proposed procedure for the derivation of FRCs.
Cross-section, velocity, and bedload data at two erosion sites on the Tanana River near Fairbanks, Alaska, 1979

USGS Publications Warehouse

Burrows, Robert L.

1980-01-01

In an effort to relate river processes to vertical and lateral erosion at two sites on the Tanana River in the vicinity of Fairbanks, Alaska, measurements of depth, velocity, and bedload-transport rates were made at several sections at each site. To facilitate comparison of the river processes and ongoing erosion, compilation and graphic presentation of the velocity distributions and bedload-transport rates are presented in conjunction with cross-section configuration immediately adjacent to the area of erosion. Dry sieve analyses of the bedload samples give particle-size distribution. Approximately 85 to 95% of the material in transport at both sites was in the sand range (>0.062 millimeter <2.0 millimeter). (USGS)
Analysis and classification of topographic flow steering and inferred geomorphic processes as a function of discharge in a mountain river

NASA Astrophysics Data System (ADS)

Gore, J.; Pasternack, G. B.; Wiener, J.

2016-12-01

Process-based river classification tends to be done at reach to catchment scales assuming channels are uniform and thus differentiated by the simple specific stream power metric. In fact, mountain rivers are highly variable at subreach scales to the point that local topographic steering may be the dominant control on geomorphic processes. This study presents a new framework for characterizing how stage-dependent topographic steering varies continuously down a river, leading to a classification of subreach landforms on the basis of the geomorphic mechanism of flow convergence routing. The two remote mountain river segments were located in the 3480-km2 Yuba River, with the upper South Yuba having a substantial sediment supply from legacy hydraulic gold mining and the mainstem Yuba downstream of New Bullards Bar Dam having a restricted sediment supply. Meter-scale DEMs were produced for both cases using airborne LiDAR and survey data. DEMs were slope detrended to focus the analysis on cross-sectional variability. DEMs were then heavily smoothed to allow for automated tracing of the valley centerline, and then cross-sectional rectangles were spaced every 5 m. The average width (W) and detrended bed elevation (Z) of the wetted area was computed from the DEM for each raster for 6-7 different river stages. Both width and cross-sectionally averaged bed elevation were standardized. The product of these two variables was computed as a measure of cross-sectional area, and is termed the geomorphic covariance (Czw) series when plotted along each river corridor. Cwz was then used to classify each cross-section as one of five distinct landform types: nozzle, wide bar, normal channel, constricted pool, and oversized pool- with this classification varying with discharge such that a section could, for example, function as a nozzle during low flow but an oversized pool at high flow, or any other combination. Longitudinal profiles of bed elevation, width, covariance, and landform type were analyzed for their stage-dependent patterns to understand their geomorphic significance and to contrast the two rivers. This new method may be the first example of a hierarchical, process-based classification at the subreach scale in which one mechanism is assessed for how it varies not only in space, but as a function of discharge.
Roof Plans: Section "CC", Roof Plan; Roof Framing Plans: Section ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Roof Plans: Section "C-C", Roof Plan; Roof Framing Plans: Section "C-C", Section "D-D"; Roof Framing Sections: Cross Section "G-G", Cross Section "H-H" - Fort Washington, Fort Washington Light, Northeast side of Potomac River at Fort Washington Park, Fort Washington, Prince George's County, MD
Butterfly Dam, Cross section AA/South Elevation at Movable Leaf, Longitudinal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Butterfly Dam, Cross section A-A/South Elevation at Movable Leaf, Longitudinal Section B-B - Chicago Sanitary and Ship Canal, Butterfly Dam, Illinois Waterway River Mile 293.1, Lockport, Will County, IL
Hydraulic characteristics of the New River in the New River Gorge National River, West Virginia

USGS Publications Warehouse

Wiley, J.B.; Appel, David H.

1989-01-01

Traveltime, dispersion, water-surface and streambed profiles, and cross-section data were collected for use in application of flow and solute-transport models to the New River in the New River Gorge National River, West Virginia. Dye clouds subjected to increasing and decreasing flow rates (unsteady flow) showed that increasing flows shorten the cloud and decreasing flows lengthen the cloud. After the flow rate was changed and the flow was again steady, traveltime and dispersion characteristics were determined by the new rate of flow. Seven stage/streamflow relations identified the general changes of stream geometry throughout the study reach. Channel cross sections were estimated for model input. Low water and streambed profiles were developed from surveyed water surface elevations and water depths. (USGS)
Subsurface stratigraphic cross sections of cretaceous and lower tertiary rocks in the Wind River Basin, central Wyoming: Chapter 9 in Petroleum systems and geologic assessment of oil and gas resources in the Wind River Basin Province, Wyoming

USGS Publications Warehouse

Finn, Thomas M.

2007-01-01

The stratigraphic cross sections presented in this report were constructed as part of a project conducted by the U.S. Geological Survey to characterize and evaluate the undiscovered oil and gas resources of the Wind River Basin (WRB) in central Wyoming. The primary purpose of the cross sections is to show the stratigraphic framework and facies relations of Cretaceous and lower Tertiary rocks in this large, intermontane structural and sedimentary basin, which formed in the Rocky Mountain foreland during the Laramide orogeny (Late Cretaceous through early Eocene time). The WRB is nearly 200 miles (mi) long, 70 mi wide, and encompasses about 7,400 square miles (mi2) (fig. 1). The basin is structurally bounded by the Owl Creek and Bighorn Mountains on the north, the Casper arch on the east, the Granite Mountains on the south, and the Wind River Range on the west.
Alterations of channel parameters in response to river regulation works since 1840 on the Lower Tisza River (Hungary)

NASA Astrophysics Data System (ADS)

Kiss, Tímea; Fiala, Károly; Sipos, György

2008-06-01

In the last few years an increase in the frequency and magnitude of floods was detected on the Tisza River, endangering large areas of Hungary. The causes of these record floods were complex, including both natural and human induced factors. This paper focuses on river management works and their effect on planimetric and cross-sectional parameters, with special attention to the flood conductivity changes to the river channel. During 19th century river regulation works, half of the total length of the Tisza River was altered by cut-offs, while in the 20th century mostly revetments and groynes were constructed. Subsequently, horizontal and vertical channel parameters have changed considerably due to semi-natural bed processes. In order to reveal changes, hydrological map series (1842, 1890, 1929, 1957, 1976 and 1999) and cross-sectional surveys from the same dates were analysed. Prior to the intensive human interventions (before 1890s) the river's course was highly sinuous with some very sharp bends. Due to cut-offs both the length and sinuosity of the Tisza River decreased by 35%, while the lengths of straight sections and the river's slope doubled. As a consequence the river incised by up to 3.8 m until the 1929 survey, resulting better flood conductivity, which improved flood safety. In the 1920s river management favoured bank stabilisation in order to stop the lateral migration of the channel. Despite these measures, meander development has continued, however, in a distorted manner. This is reflected by the opposing processes of lengthening centre-line on the one hand and gradually decreasing radius of curvature on the other. These processes can be explained by the continuous development of natural point-bars on the convex bank, and the lack of lateral retreat on the concave stabilised bank. The width of the river decreased by 17-45%, while its mean and maximum depth increased by 5-48%. The area of cross-sections influenced by revetments decreased by 6-19%, resulting in a 6-15% decline in flood conductivity. The non-stabilised sections were influenced by upstream revetments. Therefore, their parameters show similar changes, but with a smaller rate. At present, the flood conductivity of the channel is worse than it was in its natural state. In all, it was found that the ongoing process of cross-sectional distortion is a significant factor in increasing flood stage and hazard, and high floods can be expected more frequently in the future partly due to this factor.
The Application of the Specific Gage Technique and Aerial Photographs in Kaskaskia River Degradation Studies

NASA Astrophysics Data System (ADS)

Du, X.

2008-12-01

The Kaskaskia River basin contains 136,000 acres of bottomland forest, the largest contiguous tract of bottomland forest remaining in the state of Illinois. Since the 1960's, the Carlyle Lake Dam impoundment and channelization activities have altered the natural hydrologic and ecological equilibrium of the Kaskaskia River. Morphological changes of the river channel have necessitated conservation and restoration efforts to create and maintain the sustainability, diversity, health, and connectivity of the river watershed. This study utilized the specific gage technique and historical aerial photographs to investigate the spatial and temporal changes of the river. Historical daily discharge and daily stage data from the Carlyle (1966 to 2002) and Venedy Station gages (1984 to 2003) were analyzed. Logs of daily discharge data were used to generate annual rating curves. The best fit equations were produced from annual rating regressions. A stage associated with a chosen reference discharge, the minimum available discharge (MAD), was calculated. A stage decreasing/increasing trend was used as a primary indicator of channel bed incision/aggradation. Pseudo specific gage analysis (PSGA) was used to model channel cross sectional geometry changes over time. PSGA applied similar procedures as compared to the specific gage technique. Instead of using the stage variable, PSGA utilized cross sectional width, cross-sectional area, mean velocity and gage height individually. At each gage, the historical change of each cross sectional parameter was plotted against the log of discharge. Ratings of specific stages, specific cross sectional width, specific depth, specific area, and specific velocity associated with the chosen discharge, MAD, were produced. The decreasing/increasing trend of each parameter mentioned above corresponded with changes of channel cross sectional geometries over time. Historical aerial photographs were also used to assess the bankfull channel width changing rates during the pre and post modification period. The statistical significance of the regression trendlines from the specific gage analyses and PSGA was tested. Results suggested that there was no significant channel bed incision trend near the river gages within the studied time period. A statistically significant increase in channel width changing rates was found during post-modification period. Following the channelization and dam construction on the Kaskaskia River, substantial channel bed widening has accelerated bank erosion and associated channel morphology change, which has consequently resulted in a net loss of riparian habitat in this important bottomland forest corridor in southern Illinois, USA.
Simplified stratigraphic cross sections of the Eocene Green River Formation in the Piceance Basin, northwestern Colorado

USGS Publications Warehouse

Dietrich, John D.; Johnson, Ronald C.

2013-01-01

Thirteen stratigraphic cross sections of the Eocene Green River Formation in the Piceance Basin of northwestern Colorado are presented in this report. Originally published in a much larger and more detailed form by Self and others (2010), they are shown here in simplified, page-size versions that are easily accessed and used for presentation purposes. Modifications to the original versions include the elimination of the detailed lithologic columns and oil-yield histograms from Fischer assay data and the addition of ground-surface lines to give the depth of the various oil shale units shown on the cross section.
Cross-Sectional Data for Selected Reaches of the Chattahoochee River within the Chattahoochee River National Recreation Area, Georgia, 2004

USGS Publications Warehouse

Dalton, Melinda S.

2006-01-01

This report presents hydrologic data for selected reaches of the Chattahoochee River within the Chattahoochee River National Recreation Area (CRNRA). Data about transect location, width, depth, and velocity of flow for selected reaches of the river are presented in tabular form. The tables contain measurements collected from shoal and run habitats identified as critical sites for the CRNRA. In shoal habitats, measurements were collected while wading using a digital flowmeter and laser range finder. In run habitats, measurements were collected using acoustic Doppler current profiling. Fifty-three transects were established in six reaches throughout the CRNRA; 24 in shoal habitat, 26 in run habitat, and 3 in pool habitat. Illustrations in this report contain information about study area location, hydrology, transect locations, and cross-sectional information. A study area location figure is followed by figures identifying locations of transects within each individual reach. Cross-sectional information is presented for each transect, by reach, in a series of graphs. The data presented herein can be used to complete preliminary habitat assessments for the Chattahoochee River within the CRNRA. These preliminary assessments can be used to identify reaches of concern for future impacts associated with continual development in the Metropolitan Atlanta area and potential water allocation agreements between Georgia, Florida, and Alabama.
Detailed north-south cross section showing environments of deposition, organic richness, and thermal maturities of lower Tertiary rocks in the Uinta Basin, Utah

USGS Publications Warehouse

Johnson, Ronald C.

2014-01-01

The Uinta Basin of northeast Utah has produced large amounts of hydrocarbons from lower Tertiary strata since the 1960s. Recent advances in drilling technologies, in particular the development of efficient methods to drill and hydraulically fracture horizontal wells, has spurred renewed interest in producing hydrocarbons from unconventional low-permeability dolomite and shale reservoirs in the lacustrine, Eocene Green River Formation. The Eocene Green River Formation was deposited in Lake Uinta, a long-lived saline lake that occupied the Uinta Basin, the Piceance Basin to the east, and the intervening Douglas Creek arch. The focus of recent drilling activity has been the informal Uteland Butte member of the Green River Formation and to a much lesser extent the overlying R-0 oil shale zone of the Green River Formation. Initial production rates ranging from 500 to 1,500 barrels of oil equivalent per day have been reported from the Uteland Butte member from horizontal well logs that are as long as 4,000 feet (ft);. The cross section presented here extends northward from outcrop on the southern margin of the basin into the basin’s deep trough, located just south of the Uinta Mountains, and transects the area where this unconventional oil play is developing. The Monument Butte field, which is one of the fields located along this line of section, has produced hydrocarbons from conventional sandstone reservoirs in the lower part of the Green River Formation and underlying Wasatch Formation since 1981. A major fluvial-deltaic system entered Lake Uinta from the south, and this new line of section is ideal for studying the effect of the sediments delivered by this drainage on hydrocarbon reservoirs in the Green River Formation. The cross section also transects the Greater Altamont-Bluebell field in the deepest part of the basin, where hydrocarbons have been produced from fractured, highly overpressured marginal lacustrine and fluvial reservoirs in the Green River, Wasatch, and North Horn Formations since 1970. Datum for the cross section is sea level so that hydrocarbon source rocks and reservoir rocks could be integrated into the structural framework of the basin.
Data collection for a time-of-travel and dispersion study on the Coosa River near Childersburg, Alabama

USGS Publications Warehouse

Gardner, R.A.

1985-01-01

Approximately 2,300 dye-tracer samples were collected and analyzed during a 5-day time-of-travel study on a 23-mile reach of the Coosa River between Logan Martin and Lay dams near Childersburg, Alabama, October 27 to 31, 1984. Rhodamine WT was used as the tracer-dye. Unsteady flow conditions prevailed in the study reach. The rate of movement of the dye cloud between sampling cross sections ranged from 0.15 to 1.36 feet per second. The average rate of movement of the dye cloud between the injection cross section and the downstream sampling cross section was 0.42 foot per second. (USGS)
Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

USGS Publications Warehouse

Berenbrock, Charles E.

2015-01-01

The effects of reduced cross-sectional data points on steady-flow profiles were also determined. Thirty-five cross sections of the original steady-flow model of the Kootenai River were used. These two methods were tested for all cross sections with each cross section resolution reduced to 10, 20 and 30 data points, that is, six tests were completed for each of the thirty-five cross sections. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but this was not always the case, especially in the braided reach. Differences were smaller for reduced cross sections developed by the genetic algorithm method than the standard algorithm method.
Strategies and equipment for sampling suspended sediment and associated toxic chemicals in large rivers - with emphasis on the Mississippi River

USGS Publications Warehouse

Meade, R.H.; Stevens, H.H.

1990-01-01

A Lagrangian strategy for sampling large rivers, which was developed and tested in the Orinoco and Amazon Rivers of South America during the early 1980s, is now being applied to the study of toxic chemicals in the Mississippi River. A series of 15-20 cross-sections of the Mississippi mainstem and its principal tributaries is sampled by boat in downstream sequence, beginning upriver of St. Louis and concluding downriver of New Orleans 3 weeks later. The timing of the downstream sampling sequence approximates the travel time of the river water. Samples at each cross-section are discharge-weighted to provide concentrations of dissolved and suspended constituents that are converted to fluxes. Water-sediment mixtures are collected from 10-40 equally spaced points across the river width by sequential depth integration at a uniform vertical transit rate. Essential equipment includes (i) a hydraulic winch, for sensitive control of vertical transit rates, and (ii) a collapsible-bag sampler, which allows integrated samples to be collected at all depths in the river. A section is usually sampled in 4-8 h, for a total sample recovery of 100-120 l. Sampled concentrations of suspended silt and clay are reproducible within 3%.
Hydraulic conditions of flood flows in a Polish Carpathian river subjected to variable human impacts

NASA Astrophysics Data System (ADS)

Radecki-Pawlik, Artur; Czech, Wiktoria; Wyżga, Bartłomiej; Mikuś, Paweł; Zawiejska, Joanna; Ruiz-Villanueva, Virginia

2016-04-01

Channel morphology of the Czarny Dunajec River, Polish Carpathians, has been considerably modified as a result of channelization and gravel-mining induced channel incision, and now it varies from a single-thread, incised or regulated channel to an unmanaged, multi-thread channel. We investigated effects of these distinct channel morphologies on the conditions for flood flows in a study of 25 cross-sections from the middle river course where the Czarny Dunajec receives no significant tributaries and flood discharges increase little in the downstream direction. Cross-sectional morphology, channel slope and roughness of particular cross-section parts were used as input data for the hydraulic modelling performed with the 1D steady-flow HEC-RAS model for discharges with recurrence interval from 1.5 to 50 years. The model for each cross-section was calibrated with the water level of a 20-year flood from May 2014, determined shortly after the flood on the basis of high-water marks. Results indicated that incised and channelized river reaches are typified by similar flow widths and cross-sectional flow areas, which are substantially smaller than those in the multi-thread reach. However, because of steeper channel slope in the incised reach than in the channelized reach, the three river reaches differ in unit stream power and bed shear stress, which attain the highest values in the incised reach, intermediate values in the channelized reach, and the lowest ones in the multi-thread reach. These patterns of flow power and hydraulic forces are reflected in significant differences in river competence between the three river reaches. Since the introduction of the channelization scheme 30 years ago, sedimentation has reduced its initial flow conveyance by more than half and elevated water stages at given flood discharges by about 0.5-0.7 m. This partly reflects a progressive growth of natural levees along artificially stabilized channel banks. By contrast, sediments of natural levees deposited along the multi-thread channel and subsequently eroded in the course of lateral channel migration and floodplain reworking; as a result, they do not reduce the conveyance of floodplain flows in this reach. This study was performed within the scope of the Research Project DEC-2013/09/B/ST10/00056 financed by the National Science Centre of Poland.
Use of multispectral satellite remote sensing to assess mixing of suspended sediment downstream of large river confluences

NASA Astrophysics Data System (ADS)

Umar, M.; Rhoads, Bruce L.; Greenberg, Jonathan A.

2018-01-01

Although past work has noted that contrasts in turbidity often are detectable on remotely sensed images of rivers downstream from confluences, no systematic methodology has been developed for assessing mixing over distance of confluent flows with differing surficial suspended sediment concentrations (SSSC). In contrast to field measurements of mixing below confluences, satellite remote-sensing can provide detailed information on spatial distributions of SSSC over long distances. This paper presents a methodology that uses remote-sensing data to estimate spatial patterns of SSSC downstream of confluences along large rivers and to determine changes in the amount of mixing over distance from confluences. The method develops a calibrated Random Forest (RF) model by relating training SSSC data from river gaging stations to derived spectral indices for the pixels corresponding to gaging-station locations. The calibrated model is then used to predict SSSC values for every river pixel in a remotely sensed image, which provides the basis for mapping of spatial variability in SSSCs along the river. The pixel data are used to estimate average surficial values of SSSC at cross sections spaced uniformly along the river. Based on the cross-section data, a mixing metric is computed for each cross section. The spatial pattern of change in this metric over distance can be used to define rates and length scales of surficial mixing of suspended sediment downstream of a confluence. This type of information is useful for exploring the potential influence of various controlling factors on mixing downstream of confluences, for evaluating how mixing in a river system varies over time and space, and for determining how these variations influence water quality and ecological conditions along the river.
Temporal Differences in Flow Depth and Velocity Distributions and Hydraulic Microhabitats Near Bridges of the Lower Platte River, Nebraska, 1934-2006

USGS Publications Warehouse

Ginting, Daniel; Zelt, Ronald B.

2008-01-01

As part of a collaborative study of the cumulative impacts on stream and riparian ecology of water and channel management practices in the lower Platte River, Nebraska, this report describes a study by the U.S. Geological Survey in cooperation with the Lower Platte South Natural Resources District that summarizes: (1) temporal differences in distribution of streamflow depth, velocity, and microhabitats among five discrete 11-water-year periods 1934-44, 1951-61, 1966-76, 1985-95, and 1996-2006, and (2) the effects of bridge proximity on distribution of streamflow depth, velocity, and microhabitat of the Platte River when cross sections were measured at a similar discharge. The scope of the study included the four presently (2008) active streamflow-gaging stations located near bridges over the lower Platte River at North Bend, near Leshara, near Ashland, and at Louisville, Nebraska, and the most downstream streamflow-gaging station within the central Platte River segment near Duncan, Nebraska. Generally, in cases where temporal differences in streamflow depth and velocity were evident, at least one of the water-year periods from 1934 through 1995 had deeper streamflow than the recent water-year period (1996-2006). Temporal differences in distributions of streamflow depth were not strongly associated with differences in either climatic conditions or the maximum peak flow that occurred prior to the latest discharge measurement during each period. The relative cross-sectional area of most hydraulic niches did not differ among the water-year periods. Part of this apparent uniformity likely was an artifact of the broad microhabitat classification used for this study. In cases where temporal differences in relative cross-sectional area of hydraulic niches were evidenced, the differences occurred during high- and low-flow conditions, not during median flow conditions. The temporal differences in relative cross-sectional area were found more frequently for hydraulic niches defined by moderate and fast velocities than for hydraulic niches defined by slow velocities. Generally, any significant increase or decrease in the relative cross-sectional areas of hydraulic niches during the water-year periods from 1934 through 1995 had disappeared during the most recent water-year period, 1996-2006. Deep-Swift niche was the predominant hydraulic niche for all near-bridge sites on the lower Platte River for high- and median-flow conditions. The Deep-Swift niche also was the predominant niche for the near-bridge sites near Ashland and at Louisville for low-flow conditions; for the near-bridge sites at North Bend and near Leshara, streamflow cross-sectional areas during low-flow conditions were shared among the Shallow-Moderate, Intermediate-Moderate, Intermediate-Swift, and Deep-Swift hydraulic niches. For the near-bridge site near Duncan, the site farthest downstream in the central Platte River system, the Deep-Swift hydraulic niche was predominant only during high-flow conditions; during median- and low-flow conditions the relative cross-sectional area was shared among the Shallow-Slow, Shallow-Moderate, Intermediate-Moderate, and Intermediate-Swift hydraulic niches. Significant temporal differences in the relative cross-sectional area of the Deep-Swift hydraulic niche were found for sites near the two farthest downstream bridges near Ashland and at Louisville, but only for low-flow conditions. The Deep-Swift microhabitat was of special interest because it is the preferred hydraulic habitat during the adult life of the endangered pallid sturgeon (Scaphirhynchus albus). Temporal differences in relative cross-sectional areas of the Glide low-flow geomorphic microhabitat that contained the Deep-Swift hydraulic niche also indicated that relative cross-sectional areas of the Glide during the 1951-61 and 1996-2006 water-year periods were lower than during the 1966-76 period. The temporal differences indicated that any significant temporal chang

Reduced channel conveyance on the Wichita River at Wichita Falls, Texas, 1900-2009

USGS Publications Warehouse

Winters, Karl; Baldys, Stanley; Schreiber, Russell

2010-01-01

Recent floods on the Wichita River at Wichita Falls, Texas, have reached higher stages compared to historical floods of similar magnitude discharges. The U.S. Geological Survey (USGS) has operated streamflow-gaging station 07312500 Wichita River at Wichita Falls, Tex., since 1938 and flood measurements near the location of the present gage were first made in 1900. Floods recorded in 2007 and 2008 at this gaging station, including the record flood of June 30, 2007, reached higher stages compared to historical floods before 1972 of similar peak discharges. For flood measurements made at stages of more than 18 feet, peak stages were about 1 to 3 feet higher compared to peak stages of similar peak discharges measured before 1972. Flood measurements made at stages of more than 18 feet also indicate a decrease in the measured mean velocity from about 3.5 to about 2.0 feet per second from 1941 to 2008. The increase in stage and decrease in streamflow velocity for similar magnitude floods indicates channel conveyance has decreased over time. A study to investigate the causes of reduced channel conveyance in the Wichita River reach from Loop 11 downstream to River Road in Wichita Falls was done by the USGS in cooperation with the City of Wichita Falls. Historical photographs indicate substantial growth of riparian vegetation downstream from Loop 11 between 1950 and 2009. Aerial photographs taken between 1950 and 2008 also indicate an increase in riparian vegetation. Twenty-five channel cross sections were surveyed by the USGS in this reach in 2009. These cross sections were located at bridge crossings or collocated with channel cross sections previously surveyed in 1986 for use in a floodplain mapping study by the Federal Emergency Management Agency. Four channel cross sections 3,400 to 11,900 feet downstream from Martin Luther King Jr. Boulevard indicate narrowing of the channel. The remaining channel cross sections surveyed in 2009 by the USGS compared favorably with cross sections surveyed in 1986 for the Federal Emergency Management Agency, with no substantial differences noted. Comparison of channel cross sections surveyed in 2009 to those from historic bridge plans indicate no change in cross section has occurred at most of the bridges from Loop 11 downstream to River Road in Wichita Falls, except for obstructions noted at the Scott Avenue bridge and Martin Luther King Jr. bridge. Although obstructions in the channel at these bridges only partially block flow, they could also be contributing to reduced channel conveyance. Step-backwater profiles were used by the USGS to verify channel roughness. The main channel roughness coefficients (Manning's n values) from 2009 surveys were virtually unchanged from those used in a 1991 hydraulic model done for the Federal Emergency Management Agency. The average overbank roughness coefficient (Manning's n value) was 0.15, more than double the value of 0.06 used in the 1991 hydraulic model. Increased overbank vegetation has resulted in higher stages conveying the same amount of discharge, particularly for discharges more than 4,000 cubic feet per second.
78 FR 36212 - Availability of Application for the Proposal To Replace the Existing Movable I-5 Bridge Across...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-17

... materials for the Columbia River Crossing. The document contained an incorrect phone number for the Columbia... Columbia River Crossing.'' (78 FR 26380). Mistakenly, the phone number for the person listed in the FOR FURTHER INFORMATION CONTACT section was incorrect. The correct phone number for Gary Greene, Columbia...
Hydraulic-Geometry Relations for Rivers in Coastal and Central Maine

USGS Publications Warehouse

Dudley, Robert W.

2004-01-01

Hydraulic-geometry relations (curves) were derived for 15 sites on 12 rivers in coastal and central Maine on the basis of site-specific (at-a-station) hydraulic-geometry relations and hydraulic models. At-a-station hydraulic-geometry curves, expressed as well-established power functions, describe the relations between channel geometry, velocity, and flow at a given point on a river. The derived at-a-station hydraulic-geometry curves indicate that, on average, a given increase in flow at a given river cross section in the study area will be nearly equally conveyed by increases in velocity and channel cross-sectional area. Regional curves describing the bankfull streamflow and associated channel geometry as functions of drainage area were derived for use in stream-channel assessment and restoration projects specific to coastal and central Maine. Regional hydraulic-geometry curves were derived by combining hydraulic-geometry information for 15 river cross sections using bankfull flow as the common reference streamflow. The exponents of the derived regional hydraulic-geometry relations indicate that, in the downstream direction, most of the conveyance of increasing contribution of flow is accommodated by an increase in cross-sectional area?with about 50 percent of the increase in flow accommodated by an increase in channel width, and 32 percent by an increase in depth. The remaining 18 percent is accommodated by an increase in streamflow velocity. On an annual-peak-series basis, results of this study indicate that the occurrence of bankfull streamflow for rivers in Maine is more frequent than the 1.5-year streamflow. On a flow-duration basis, bankfull streamflow for rivers in coastal and central Maine is equaled or exceeded approximately 8.1 percent of the time on mean?or about 30 days a year. Bankfull streamflow is roughly three times that of the mean annual streamflow for the sites investigated in this study. Regional climate, snowmelt hydrology, and glacial geology may play important roles in dictating the magnitude and frequency of occurrence of bankfull streamflows observed for rivers in coastal and central Maine.
Calculating e-flow using UAV and ground monitoring

NASA Astrophysics Data System (ADS)

Zhao, C. S.; Zhang, C. B.; Yang, S. T.; Liu, C. M.; Xiang, H.; Sun, Y.; Yang, Z. Y.; Zhang, Y.; Yu, X. Y.; Shao, N. F.; Yu, Q.

2017-09-01

Intense human activity has led to serious degradation of basin water ecosystems and severe reduction in the river flow available for aquatic biota. As an important water ecosystem index, environmental flows (e-flows) are crucial for maintaining sustainability. However, most e-flow measurement methods involve long cycles, low efficiency, and transdisciplinary expertise. This makes it impossible to rapidly assess river e-flows at basin or larger scales. This study presents a new method to rapidly assessing e-flows coupling UAV and ground monitorings. UAV was firstly used to calculate river-course cross-sections with high-resolution stereoscopic images. A dominance index was then used to identify key fish species. Afterwards a habitat suitability index, along with biodiversity and integrity indices, was used to determine an appropriate flow velocity with full consideration of the fish spawning period. The cross-sections and flow velocity values were then combined into AEHRA, an e-flow assessment method for studying e-flows and supplying-rate. To verify the results from this new method, the widely used Tennant method was employed. The root-mean-square errors of river cross-sections determined by UAV are less than 0.25 m, which constitutes 3-5% water-depth of the river cross-sections. In the study area of Jinan city, the ecological flow velocity (VE) is equal to or greater than 0.11 m/s, and the ecological water depth (HE) is greater than 0.8 m. The river ecosystem is healthy with the minimum e-flow requirements being always met when it is close to large rivers, which is beneficial for the sustainable development of the water ecosystem. In the south river channel of Jinan, the upstream flow mostly meets the minimum e-flow requirements, and the downstream flow always meets the minimum e-flow requirements. The north of Jinan consists predominantly of artificial river channels used for irrigation. Rainfall rarely meets the minimum e-flow and irrigation water requirements. We suggest that the water shortage problem can be partly solved by diversion of the Yellow River. These results can provide useful information for ecological operations and restoration. The method used in this study for calculating e-flow based on a combination of UAV and ground monitoring can effectively promote research progress into basin e-flow, and provide an important reference for e-flow monitoring around the world.
An acoustic doppler current profiler survey of flow velocities in St. Clair River, a connecting channel of the Great Lakes

USGS Publications Warehouse

Holtschlag, David J.; Koschik, John A.

2003-01-01

Acoustic Doppler current profilers (ADCP) were used to measure flow velocities in St. Clair River during a survey in May and June of 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. The survey provides 2.7 million point velocity measurements at 104 cross sections. Sections are spaced about 1,630 ft apart along the river from Port Huron to Algonac, Michigan, a distance of 28.6 miles. Two transects were obtained at each cross section, one in each direction across the river. Along each transect, velocity profiles were obtained 2-4 ft apart. At each velocity profile, average water velocity data were obtained at 1.64 ft intervals of depth. The raw position and velocity data from the ADCP field survey were adjusted for local magnetic anomalies using global positioning system (GPS) measurements at the end points of the transects. The adjusted velocity and ancillary data can be retrieved through the internet and extracted to column-oriented data files.
Application of acoustic velocity meters for gaging discharge of three low-velocity tidal streams in the St. Johns River basin, northeast Florida

USGS Publications Warehouse

Sloat, J.V.; Gain, W.S.

1995-01-01

Index-velocity data collected with acoustic velocity meters, stage data, and cross-sectional area data were used to calculate discharge at three low-velocity, tidal streamflow stations in north-east Florida. Discharge at three streamflow stations was computed as the product of the channel cross-sectional area and the mean velocity as determined from an index velocity measured in the stream using an acoustic velocity meter. The tidal streamlflow stations used in the study were: Six Mile Creek near Picolata, Fla.; Dunns Creek near Satsuma, Fla.; and the St. Johns River at Buffalo Bluff. Cross-sectional areas at the measurement sections ranged from about 3,000 square feet at Six Mile Creek to about 18,500 square feet at St. Johns River at Buffalo Bluff. Physical characteristics for all three streams were similar except for drainage area. The topography primarily is low-relief, swampy terrain; stream velocities ranged from about -2 to 2 feet per second; and the average change in stage was about 1 foot. Instantaneous discharge was measured using a portable acoustic current meter at each of the three streams to develop a relation between the mean velocity in the stream and the index velocity measured by the acoustic velocity meter. Using least-squares linear regression, a simple linear relation between mean velocity and index velocity was determined. Index velocity was the only significant linear predictor of mean velocity for Six Mile Creek and St. Johns River at Buffalo Bluff. For Dunns Creek, both index velocity and stage were used to develop a multiple-linear predictor of mean velocity. Stage-area curves for each stream were developed from bathymetric data. Instantaneous discharge was computed by multiplying results of relations developed for cross-sectional area and mean velocity. Principal sources of error in the estimated discharge are identified as: (1) instrument errors associated with measurement of stage and index velocity, (2) errors in the representation of mean daily stage and index velocity due to natural variability over time and space, and (3) errors in cross-sectional area and mean-velocity ratings based on stage and index velocity. Standard errors for instantaneous discharge for the median cross-sectional area for Six Mile Creek, Dunns Creek, and St. Johns River at Buffalo Bluff were 94,360, and 1,980 cubic feet per second, respectively. Standard errors for mean daily discharge for the median cross-sectional area for Six Mile Creek, Dunns Creek, and St. Johns River at Buffalo Bluff were 25, 65, and 455 cubic feet per second, respectively. Mean daily discharge at the three sites ranged from about -500 to 1,500 cubic feet per second at Six Mile Creek and Dunns Creek and from about -500 to 15,000 cubic feet per second on the St. Johns River at Buffalo Bluff. For periods of high discharge, the AVM index-velocity method tended to produce estimates accurate with 2 to 6 percent. For periods of moderate discharge, errors in discharge may increase to more than 50 percent. At low flows, errors as a percentage of discharge increase toward infinity.
Stability evaluation of modernized bank protections in a culvert construction

NASA Astrophysics Data System (ADS)

Cholewa, Mariusz; Plesiński, Karol; Kamińska, Katarzyna; Wójcik, Izabela

2018-02-01

The paper presents stability evaluation of the banks of the Wilga River on a chosen stretch in Koźmice Wielkie, Małopolska Province. The examined stretch included the river bed upstream from the culvert on a district road. The culvert construction, built over four decades ago, was disassembled in 2014. The former construction, two pipes that were 1.4 m in diameter, was entirely removed. The investor decided to build a new construction in the form of insitu poured reinforced concrete with a 4 x 2 m cross section. Change of geometry and different location in relation to the river current caused increase in the flow velocity and, as a consequence, erosion of both protected and natural banks. Groundwater conditions were determined based on the geotechnical tests that were carried out on soil samples taken from the banks and the river bed. Stability calculations of natural slopes of the Wilga River and the ones protected with riprap indicate mistakes in the design project concerning construction of the river banks. The purpose of the study was to determine the stability of the Wilga River banks on a selected section adjacent to the rebuilt culvert. Stability of a chosen cross section was analysed in the paper. Presented conclusions are based on the results of geotechnical tests and numerical calculations.
Consistent initial conditions for the Saint-Venant equations in river network modeling

NASA Astrophysics Data System (ADS)

Yu, Cheng-Wei; Liu, Frank; Hodges, Ben R.

2017-09-01

Initial conditions for flows and depths (cross-sectional areas) throughout a river network are required for any time-marching (unsteady) solution of the one-dimensional (1-D) hydrodynamic Saint-Venant equations. For a river network modeled with several Strahler orders of tributaries, comprehensive and consistent synoptic data are typically lacking and synthetic starting conditions are needed. Because of underlying nonlinearity, poorly defined or inconsistent initial conditions can lead to convergence problems and long spin-up times in an unsteady solver. Two new approaches are defined and demonstrated herein for computing flows and cross-sectional areas (or depths). These methods can produce an initial condition data set that is consistent with modeled landscape runoff and river geometry boundary conditions at the initial time. These new methods are (1) the pseudo time-marching method (PTM) that iterates toward a steady-state initial condition using an unsteady Saint-Venant solver and (2) the steady-solution method (SSM) that makes use of graph theory for initial flow rates and solution of a steady-state 1-D momentum equation for the channel cross-sectional areas. The PTM is shown to be adequate for short river reaches but is significantly slower and has occasional non-convergent behavior for large river networks. The SSM approach is shown to provide a rapid solution of consistent initial conditions for both small and large networks, albeit with the requirement that additional code must be written rather than applying an existing unsteady Saint-Venant solver.
Decadal changes in channel morphology of a freely meandering river—Powder River, Montana, 1975–2016

USGS Publications Warehouse

Moody, John A.; Meade, Robert H.

2018-03-19

Few studies exist on the long-term geomorphic effects of floods. However, the U.S. Geological Survey (USGS) was able to begin such a study after a 50-year recurrence interval flood in 1978 because 20 channel cross sections along a 100-kilometer reach of river were established in 1975 and 1977 as part of a study for a proposed dam on Powder River in southeastern Montana. These cross-section measurements (data for each channel cross section are available at the USGS ScienceBase website) have been repeated about 30 times during four decades (1975–2016) and provide a unique dataset for understanding long-term changes in channel morphology caused by an extreme flood and a spectrum of annual floods.Changes in channel morphology of a 100-kilometer reach of Powder River are documented in a series of narratives for each channel cross section that include a time series of photographs as a record of these changes. The primary change during the first decade (1975–85) was the rapid vertical growth of a new inset flood plain within the flood-widened channel. Changes during the second decade (1985–95) were characterized by slower growth of the flood plain, and the effects of ice-jam floods typical of a northward-flowing river. Changes during the third decade (1995–2005) showed little vertical growth of the inset flood plain, which had reached a height that limited overbank deposition. And changes during the final decade (2005–16) covered in this report showed that, because the new inset flood plain had reached a limiting height, the effects of the large annual flood of 2008 (largest flood since 1978) were relatively small compared to smaller floods in previous decades. Throughout these four decades, the riparian vegetation, which interacts with the river, has undergone a gradual but substantial change that may have lasting effects on the channel morphology.
Water quality of the tidal Potomac River and Estuary; hydrologic data report supplement, 1979 through 1981 water years

USGS Publications Warehouse

Coupe, R.H.; Webb, W.E.

1984-01-01

This report is a companion report to the U.S. Geological Survey 1979, 1980, and 1981 Hydrologic Data Reports of the tidal Potomac River and Estuary. It contains values of biochemical oxygen demand and specific rate constants, incident light and light attenuation measurements; numbers of phytoplankton, fecal coliform and fecal streptococci, cross-sectional averages from field measurements of dissolved oxygen, pH, specific conductance , and temperature data; and cross-sectional averages of chlorophyll data. Sewage treatment plant loads are also included. (USGS)
An overview of historical channel adjustment and selected hydraulic values in the Lower Sabine and Lower Brazos River Basins, Texas and Louisiana

USGS Publications Warehouse

Heitmuller, Franklin T.; Greene, Lauren E.; John D. Gordon, John D.

2010-01-01

The Sabine and Brazos are alluvial rivers; alluvial rivers are dynamic systems that adjust their geometry in response to changes in streamflow (discharge) and sediment load. In fluvial geomorphology, the term 'channel adjustment' refers to river channel changes in three geometric dimensions: (1) channel slope (profile); (2) the outline or shape, such as meandering or braided, projected on a horizontal plane (planform); and (3) cross-sectional form (shape). The primary objective of the study was to investigate how the channel morphology of these rivers has changed in response to reservoirs and other anthropogenic disturbances that have altered streamflow and sediment load. The results of this study are expected to aid ecological assessments in the lower Sabine River and lower Brazos River Basins for the Texas Instream Flow Program. Starting in the 1920s, several dams have been constructed on the Sabine and Brazos Rivers and their tributaries, and numerous bridges have been built and sometimes replaced multiple times, which have changed the natural flow regime and reduced or altered sediment loads downstream. Changes in channel geometry over time can reduce channel conveyance and thus streamflow, which can have adverse ecological effects. Channel attributes including cross-section form, channel slope, and planform change were evaluated to learn how each river's morphology changed over many years in response to natural and anthropogenic disturbances. Climate has large influence on the hydrologic regimes of the lower Sabine and lower Brazos River Basins. Equally important as climate in controlling the hydrologic regime of the two river systems are numerous reservoirs that regulate downstream flow releases. The hydrologic regimes of the two rivers and their tributaries reflect the combined influences of climate, flow regulation, and drainage area. Historical and contemporary cross-sectional channel geometries at 15 streamflow-gaging stations in the lower Sabine and lower Brazos River Basins were evaluated. An in-depth discussion of results from streamflow-gaging station 08028500 Sabine River near Bon Weir, Tex., is featured here as an example of the analyses that were done at each station.
Surface-water-quality assessment of the Upper Illinois River basin in Illinois, Indiana, and Wisconsin; cross-sectional and depth variation of water-quality constituents and properties in the Upper Illinois River basin, 1987-88

USGS Publications Warehouse

Marron, Donna C.; Blanchard, Stephen F.

1995-01-01

Data on water velocity, temperature, specific con- ductance, pH, dissolved oxygen concentration, chlorophyll concentration, suspended sediment con- centration, fecal-coliform counts, and the percen- tage of suspended sediment finer than 62 micrometers ranged up to 21 percent; and cross-section coefficients of variation of the concentrations of suspended sediment, fecal coliform, and chlorophyll ranged from 7 to 115 percent. Midchannel measure- ments of temperature, specific conductance, and pH were within 5 percent of mean cross-sectional values of these properties at the eight sampling sites, most of which appear well mixed because of the effect of dams and reservoirs. Measurements of the concentration of dissolved oxygen at various cross- section locations and at variable sampling depths are required to obtain a representative value of this constituent at these sites. The large varia- bility of concentrations of chlorophyll and suspended sediment, and fecal-coliform counts at the eight sampling sites indicates that composite rather than midchannel or mean values of these constituents are likely to be most representative of the channel cross section.
27 CFR 9.178 - Columbia Gorge.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Columbia River. From this point, the boundary line— (1) Goes 1.5 miles straight north along the R9E-R10E line to the northwest corner of section 19, T3N, R10E (Hood River Quadrangle); (2) Continues 2 miles... Quadrangle); (3) Goes 4.1 miles straight north along the section line, crossing onto the Northwestern Lake...
27 CFR 9.178 - Columbia Gorge.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Columbia River. From this point, the boundary line— (1) Goes 1.5 miles straight north along the R9E-R10E line to the northwest corner of section 19, T3N, R10E (Hood River Quadrangle); (2) Continues 2 miles... Quadrangle); (3) Goes 4.1 miles straight north along the section line, crossing onto the Northwestern Lake...
27 CFR 9.178 - Columbia Gorge.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Columbia River. From this point, the boundary line— (1) Goes 1.5 miles straight north along the R9E-R10E line to the northwest corner of section 19, T3N, R10E (Hood River Quadrangle); (2) Continues 2 miles... Quadrangle); (3) Goes 4.1 miles straight north along the section line, crossing onto the Northwestern Lake...
27 CFR 9.178 - Columbia Gorge.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Columbia River. From this point, the boundary line— (1) Goes 1.5 miles straight north along the R9E-R10E line to the northwest corner of section 19, T3N, R10E (Hood River Quadrangle); (2) Continues 2 miles... Quadrangle); (3) Goes 4.1 miles straight north along the section line, crossing onto the Northwestern Lake...
Flood-plain and channel aggradation of selected bridge sites in the Iowa and Skunk River basins, Iowa

USGS Publications Warehouse

Eash, D.A.

1996-01-01

Flood-plain and channel-aggradation rates were estimated at 10 bridge sites on the Iowa River upstream of Coralville Lake and at two bridge sites in the central part of the Skunk River Basin. Four measurement methods were used to quantify aggradation rates: (1) a dendrogeomorphic method that used tree-age data and sediment-deposition depths, (2) a bridge-opening cross-section method that compared historic and recent cross sections of bridge openings, (3) a stage-discharge rating-curve method that compared historic and recent stages for the 5-year flood discharge and the average discharge, and (4) nine sediment pads that were installed on the Iowa River flood plain at three bridge sites in the vicinity of Marshalltown. The sediment pads were installed prior to overbank flooding in 1993. Sediments deposited on the pads as a result of the 1993 flood ranged in depth from 0.004 to 2.95 feet. Measurement periods used to estimate average aggradation rates ranged from 1 to 98 years and varied among methods and sites. The highest aggradation rates calculated for the Iowa River Basin using the dendrogeomorphic and rating- curve measurement methods were for the State Highway 14 crossing at Marshalltown, where these highest rates were 0.045 and 0.124 feet per year, respectively. The highest aggradation rates calculated for the Skunk River Basin were for the U.S. Highway 63 crossing of the South Skunk River near Oskaloosa, where these highest rates were 0.051 and 0.298 feet per year, respectively.
23. Cross section of newly completed concrete channel and trestle ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. Cross section of newly completed concrete channel and trestle supported steel flume, 1919. Courtesy of the Mandeville Department of Special Collections, Central Library, University of California, San Diego. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA
Kinematic Modeling of Central Nepal: Thermochronometer Cooling Ages as a Constraint for Balanced Cross Sections

NASA Astrophysics Data System (ADS)

Olree, E.; Robinson, D. M.; McQuarrie, N.; Ghoshal, S.; Olsen, J.

2016-12-01

Using balanced cross sections, one can visualize a valid and admissible interpretation of the surface and subsurface data. Khanal (2014) and Cross (2014) produced two valid and admissible cross sections along the Marsyandi River in central Nepal. However, thermochronologic data adds another dimension that must be adhered to when producing valid and admissible balanced cross sections. Since the previous cross sections were produced, additional zircon-helium (ZHe) cooling ages along the Marsyandi River show ages of 1 Ma near the Main Central thrust in the hinterland to 4 Ma near the Main Boundary thrust closer to the foreland. This distribution of cooling ages requires recent uplift in the hinterland, which is not present in the cross sections. Although a restored version of the Khanal (2014) cross section is sequentially deformed using 2D Move, the kinematic sequence implied in the cross section is inconsistent with the ZHe age distribution. The hinterland dipping duplex proposed by Khanal would require cooling ages that are oldest near the Main Central thrust and young southwards toward the active ramp located 80 km north of the Main Frontal thrust. Instead, the 4 Ma age near the Main Boundary thrust and the increasingly younger ages to the north could be produced by either a foreland-dipping Lesser Himalayan duplex, which would keep active uplift in the north, or by translation of the hinterland dipping duplex southward over the ramp, moving the active thrust ramp northward. To address this problem, a new balanced cross section was produced using both new mapping through the region and the ZHe age distribution as additional constraints. The section was then restored and sequentially deformed in 2D Move. This study illustrates that multiple cross sections can be viable and admissible; however, they can still be incorrect. Thermochronology places additional constraints on the permissible geometries, and thus increases our ability to predict subsurface geometries. The next step of this project is to link the uplift and erosion implied by the kinematic sequence of the new cross section to the measured cooling history by importing the cross section kinematics into advection diffusion modeling software that predicts cooling ages.
Change detection of riverbed movements using river cross-sections and LiDAR data

NASA Astrophysics Data System (ADS)

Vetter, Michael; Höfle, Bernhard; Mandlburger, Gottfried; Rutzinger, Martin

2010-05-01

Today, Airborne LiDAR derived digital terrain models (DTMs) are used for several aspects in different scientific disciplines, such as hydrology, geomorphology or archaeology. In the field of river geomorphology, LiDAR data sets can provide information on the riverine vegetation, the level and boundary of the water body, the elevation of the riparian foreland and their roughness. The LiDAR systems in use for topographic data acquisition mainly operate with wavelengths of at least 1064nm and, thus, are not able to penetrate water. LiDAR sensors with two wavelengths are available (bathymetric LiDAR), but they can only provide elevation information of riverbeds or lakes, if the water is clear and the minimum water depth exceeds 1.5m. In small and shallow rivers it is impossible to collect information of the riverbed, regardless of the used LiDAR sensor. In this article, we present a method to derive a high-resolution DTM of the riverbed and to combine it with the LiDAR DTM resulting in a watercourse DTM (DTM-W) as a basis for calculating the changes in the riverbed during several years. To obtain such a DTM-W we use river cross-sections acquired by terrestrial survey or echo-sounding. First, a differentiation between water and land has to be done. A highly accurate water surface can be derived by using a water surface delineation algorithm, which incorporates the amplitude information of the LiDAR point cloud and additional geometrical features (e.g. local surface roughness). The second step is to calculate a thalweg line, which is the lowest flow path in the riverbed. This is achieved by extracting the lowest point of each river cross section and by fitting a B-spline curve through those points. In the next step, the centerline of the river is calculated by applying a shrinking algorithm of the water boundary polygon. By averaging the thalweg line and the centerline, a main flow path line can be computed. Subsequently, a dense array of 2D-profiles perpendicular to the flow path line is defined and the heights are computed by linear interpolation of the original cross sections. Thus, a very dense 3D point cloud of the riverbed is obtained from which a grid model of the river bed can be calculated applying any suitable interpolation technique like triangulation, linear prediction or inverse distance mapping. In a final step, the river bed model and the LiDAR DTM are combined resulting in a watercourse DTM. By computing different DTM-Ws from multiple cross section data sets, the volume and the magnitude of changes in the riverbed can be estimated. Hence, the erosion or accumulation areas and their volume changes during several years can be quantified.

Isopycnal deepening of an under-ice river plume in coastal waters: Field observations and modeling

NASA Astrophysics Data System (ADS)

Li, S. Samuel; Ingram, R. Grant

2007-07-01

The Great Whale River, located on the southeast coast of Hudson Bay in Canada, forms a large river plume under complete landfast ice during early spring. Short-term fluctuations of plume depth have motivated the present numerical study of an under-ice river plume subject to tidal motion and friction. We introduce a simple two-layer model for predicting the vertical penetration of the under-ice river plume as it propagates over a deepening topography. The topography is idealized but representative. Friction on the bottom surface of the ice cover, on the seabed, and at the plume interface is parameterized using the quadratic friction law. The extent of the vertical penetration is controlled by dimensionless parameters related to tidal motion and river outflow. Model predictions are shown to compare favorably with under-ice plume measurements from the river mouth. This study illustrates that isopycnal deepening occurs when the ice-cover vertical motion creates a reduced flow cross-section during the ebbing tide. This results in supercritical flow and triggers the downward plume penetration in the offshore. For a given river discharge, the freshwater source over a tidal cycle is unsteady in terms of discharge velocity because of the variation in the effective cross-sectional area at the river mouth, through which freshwater flows.
Water quality of the tidal Potomac River and Estuary: Hydrologic Data Reports supplement, 1979 through 1981 water years

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coupe, R.H. Jr.; Webb, W.E.

1984-01-01

This report is a companion report to the US Geological Survey 1979, 1980, and 1981 Hydrologic Data Reports of the tidal Potomac River and Estuary. The information included in this report contains values of biochemical oxygen demand and specific-rate constants, incident-light and light-attenuation measurements; numbers of phytoplankton, fecal coliform and fecal streptococci; cross-sectional averages from field measurements of dissolved oxygen, pH, specific conductance, and temperature data; and cross-sectional averages of chlorophyll data. Sewage-treatment plant loads are also included. 29 refs., 4 figs., 3 tabs.
Method based on the Laplace equations to reconstruct the river terrain for two-dimensional hydrodynamic numerical modeling

NASA Astrophysics Data System (ADS)

Lai, Ruixun; Wang, Min; Yang, Ming; Zhang, Chao

2018-02-01

The accuracy of the widely-used two-dimensional hydrodynamic numerical model depends on the quality of the river terrain model, particularly in the main channel. However, in most cases, the bathymetry of the river channel is difficult or expensive to obtain in the field, and there is a lack of available data to describe the geometry of the river channel. We introduce a method that originates from the grid generation with the elliptic equation to generate streamlines of the river channel. The streamlines are numerically solved with the Laplace equations. In the process, streamlines in the physical domain are first computed in a computational domain, and then transformed back to the physical domain. The interpolated streamlines are integrated with the surrounding topography to reconstruct the entire river terrain model. The approach was applied to a meandering reach in the Qinhe River, which is a tributary in the middle of the Yellow River, China. Cross-sectional validation and the two-dimensional shallow-water equations are used to test the performance of the river terrain generated. The results show that the approach can reconstruct the river terrain using the data from measured cross-sections. Furthermore, the created river terrain can maintain a geometrical shape consistent with the measurements, while generating a smooth main channel. Finally, several limitations and opportunities for future research are discussed.
Potential effects of deepening the St. Johns River navigation channel on saltwater intrusion in the surficial aquifer system, Jacksonville, Florida

USGS Publications Warehouse

Bellino, Jason C.; Spechler, Rick M.

2013-01-01

The U.S. Army Corps of Engineers (USACE) has proposed dredging a 13-mile reach of the St. Johns River navigation channel in Jacksonville, Florida, deepening it to depths between 50 and 54 feet below North American Vertical Datum of 1988. The dredging operation will remove about 10 feet of sediments from the surficial aquifer system, including limestone in some locations. The limestone unit, which is in the lowermost part of the surficial aquifer system, supplies water to domestic wells in the Jacksonville area. Because of density-driven hydrodynamics of the St. Johns River, saline water from the Atlantic Ocean travels upstream as a saltwater “wedge” along the bottom of the channel, where the limestone is most likely to be exposed by the proposed dredging. A study was conducted to determine the potential effects of navigation channel deepening in the St. Johns River on salinity in the adjacent surficial aquifer system. Simulations were performed with each of four cross-sectional, variable-density groundwater-flow models, developed using SEAWAT, to simulate hypothetical changes in salinity in the surficial aquifer system as a result of dredging. The cross-sectional models were designed to incorporate a range of hydrogeologic conceptualizations to estimate the effect of uncertainty in hydrogeologic properties. The cross-sectional models developed in this study do not necessarily simulate actual projected conditions; instead, the models were used to examine the potential effects of deepening the navigation channel on saltwater intrusion in the surficial aquifer system under a range of plausible hypothetical conditions. Simulated results for modeled conditions indicate that dredging will have little to no effect on salinity variations in areas upstream of currently proposed dredging activities. Results also indicate little to no effect in any part of the surficial aquifer system along the cross section near River Mile 11 or in the water-table unit along the cross section near River Mile 8. Salinity increases of up to 4.0 parts per thousand (ppt) were indicated by the model incorporating hydrogeologic conceptualizations with both a semiconfining bed over the limestone unit and a preferential flow layer within the limestone along the cross section near River Mile 8. Simulated increases in salinity greater than 0.2 ppt in this area were generally limited to portions of the limestone unit within about 75 feet of the channel on the north side of the river. The potential for saltwater to move from the river channel to the surficial aquifer system is limited, but may be present in areas where the head gradient from the aquifer to the river is small or negative and the salinity of the river is sufficient to induce density-driven advective flow into the aquifer. In some areas, simulated increases in salinity were exacerbated by the presence of laterally extensive semiconfining beds in combination with a high-conductivity preferential flow zone in the limestone unit of the surficial aquifer system and an upgradient source of saline water, such as beneath the salt marshes near Fanning Island. The volume of groundwater pumped in these areas is estimated to be low; therefore, saltwater intrusion will not substantially affect regional water supply, although users of the surficial aquifer system east of Dames Point along the northern shore of the river could be affected. Proposed dredging operations pose no risk to salinization of the Floridan aquifer system; in the study area, the intermediate confining unit ranges in thickness from more than 300 to about 500 feet and provides sufficient hydraulic separation between the surficial and Floridan aquifer systems.
Final Section of Australia's Moomba-Sydney line completed

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ives, G. Jr.

1976-12-01

Newham-Techint Gas Line JV, a joint venture between Techint Engineering (Australia) Inc. and Eric Newham (Wallerawang) Pty. Ltd., has finished construction of the final 58-mile leg of the Moomba-Sydney gas line. More than half the line is owned by The Pipeline Authority (a goverment department); the remainder belongs to the privately owned Australian Gas Light Co. Along the right-of-way, the terrain varies from an open farm belt to some 28 miles of rugged sandstone requiring blasting and drilling. In addition, the excessive number of river (2) and stream (43) crossings presented considerable problems to work crews. At the river-crossing sections,more » the pipe was installed (with a minimum of 3-ft cover) in the dry after crews temporarily dammed the river.« less
A 184-year record of river meander migration from tree rings, aerial imagery, and cross sections

NASA Astrophysics Data System (ADS)

Schook, Derek M.; Rathburn, Sara L.; Friedman, Jonathan M.; Wolf, J. Marshall

2017-09-01

Channel migration is the primary mechanism of floodplain turnover in meandering rivers and is essential to the persistence of riparian ecosystems. Channel migration is driven by river flows, but short-term records cannot disentangle the effects of land use, flow diversion, past floods, and climate change. We used three data sets to quantify nearly two centuries of channel migration on the Powder River in Montana. The most precise data set came from channel cross sections measured an average of 21 times from 1975 to 2014. We then extended spatial and temporal scales of analysis using aerial photographs (1939-2013) and by aging plains cottonwoods along transects (1830-2014). Migration rates calculated from overlapping periods across data sets mostly revealed cross-method consistency. Data set integration revealed that migration rates have declined since peaking at 5 m/year in the two decades after the extreme 1923 flood (3000 m3/s). Averaged over the duration of each data set, cross section channel migration occurred at 0.81 m/year, compared to 1.52 m/year for the medium-length air photo record and 1.62 m/year for the lengthy cottonwood record. Powder River peak annual flows decreased by 48% (201 vs. 104 m3/s) after the largest flood of the post-1930 gaged record (930 m3/s in 1978). Declining peak discharges led to a 53% reduction in channel width and a 29% increase in sinuosity over the 1939-2013 air photo record. Changes in planform geometry and reductions in channel migration make calculations of floodplain turnover rates dependent on the period of analysis. We found that the intensively studied last four decades do not represent the past two centuries.
A 184-year record of river meander migration from tree rings, aerial imagery, and cross sections

USGS Publications Warehouse

Schook, Derek M.; Rathburn, Sara L.; Friedman, Jonathan M.; Wolf, J. Marshall

2017-01-01

Channel migration is the primary mechanism of floodplain turnover in meandering rivers and is essential to the persistence of riparian ecosystems. Channel migration is driven by river flows, but short-term records cannot disentangle the effects of land use, flow diversion, past floods, and climate change. We used three data sets to quantify nearly two centuries of channel migration on the Powder River in Montana. The most precise data set came from channel cross sections measured an average of 21 times from 1975 to 2014. We then extended spatial and temporal scales of analysis using aerial photographs (1939–2013) and by aging plains cottonwoods along transects (1830–2014). Migration rates calculated from overlapping periods across data sets mostly revealed cross-method consistency. Data set integration revealed that migration rates have declined since peaking at 5 m/year in the two decades after the extreme 1923 flood (3000 m3/s). Averaged over the duration of each data set, cross section channel migration occurred at 0.81 m/year, compared to 1.52 m/year for the medium-length air photo record and 1.62 m/year for the lengthy cottonwood record. Powder River peak annual flows decreased by 48% (201 vs. 104 m3/s) after the largest flood of the post-1930 gaged record (930 m3/s in 1978). Declining peak discharges led to a 53% reduction in channel width and a 29% increase in sinuosity over the 1939–2013 air photo record. Changes in planform geometry and reductions in channel migration make calculations of floodplain turnover rates dependent on the period of analysis. We found that the intensively studied last four decades do not represent the past two centuries
Hydrologic conditions, habitat characteristics, and occurrence of fishes in the Apalachicola River floodplain, Florida; second annual report of progress, October 1993-September 1994

USGS Publications Warehouse

Light, Helen M.; Darst, Melanie R.; Grubbs, J.W.

1995-01-01

This report describes progress and interim results of the second year of a 4-year study. The purpose of the 4-year study is to describe aquatic habitat types in the Apalachicola River floodplain and quantify the amount of habitat inundated by the river at various stages. Final results will be used to determine possible effects of altered flows on floodplain habitats and their associated fish communities. The study is being conducted by the U.S. Geological Survey in cooperation with the Northwest Florida Water Management District as part of a comprehensive study of water needs throughout two large river basins in Florida, Georgia, and Alabama. By the end of the second year, approxi- mately 80 to 90 percent of field data collection was completed. Water levels at 56 floodplain and main channel locations at study sites were read numerous times during low water and once or twice during high water. Rating curves estimating the relationship between stage at a floodplain site and flow of the Apalachicola River at Chattahoochee are presented for 3 sites in the upper river. Elevation, substrate type, and amount of vegetative structure were described at 27 cross sections representing eight different floodplain tributary types at upper, middle, and lower river study sites. A summary of substrate and structure information from all cross sections is presented. Substrate and structure characteristics of floodplain habitats inundated when river flow was at record low flow, mean annual low flow, and mean flow are described for 3 cross sections in the upper river. Digital coverage of high-altitude infra-red aerial photography was processed for use in a Geographic Information System which will be used to map aquatic habitats in the third year of the study. A summary of the literature on fish utilization of floodplain habitats is described. Eighty-one percent of the species collected in the main channel of the Apalachicola River are known to occur in floodplain habitats of eastern rivers.
Historical Channel Adjustment and Estimates of Selected Hydraulic Values in the Lower Sabine River and Lower Brazos River Basins, Texas and Louisiana

USGS Publications Warehouse

Heitmuller, Franklin T.; Greene, Lauren E.

2009-01-01

The U.S. Geological Survey, in cooperation with the Texas Water Development Board, evaluated historical channel adjustment and estimated selected hydraulic values at U.S. Geological Survey streamflow-gaging stations in the lower Sabine River Basin in Texas and Louisiana and lower Brazos River Basin in Texas to support geomorphic assessments of the Texas Instream Flow Program. Channel attributes including cross-section geometry, slope, and planform change were evaluated to learn how each river's morphology changed over the years in response to natural and anthropogenic disturbances. Historical and contemporary cross-sectional channel geometries at several gaging stations on each river were compared, planform changes were assessed, and hydraulic values were estimated including mean flow velocity, bed shear stress, Froude numbers, and hydraulic depth. The primary sources of historical channel morphology information were U.S. Geological Survey hard-copy discharge-measurement field notes. Additional analyses were done using computations of selected flow hydraulics, comparisons of historical and contemporary aerial photographs, comparisons of historical and contemporary ground photographs, evaluations of how frequently stage-discharge rating curves were updated, reviews of stage-discharge relations for field measurements, and considerations of bridge and reservoir construction activities. Based on historical cross sections at three gaging stations downstream from Toledo Bend Reservoir, the lower Sabine River is relatively stable, but is subject to substantial temporary scour-and-fill processes during floods. Exceptions to this characterization of relative stability include an episode of channel aggradation at the Sabine River near Bon Wier, Texas, during the 1930s, and about 2 to 3 feet of channel incision at the Sabine River near Burkeville, Texas, since the late 1950s. The Brazos River, at gaging stations downstream from Waco, Texas, has adjusted to a combination of hydrologic, sedimentary, and anthropogenic controls. Since the 1960s, numerous point bars have vertically accreted and vegetation has encroached along the channel margins, which probably promotes channel-bed incision to compensate for a reduction in cross-sectional area. Channel incision was detected at all gaging stations along the Brazos River, and the depth of incision is greatest in the lowermost gaging stations, exemplified by about 5 feet of channel-bed incision between 1993 and 2004 at Richmond, Texas. One notable exception to this pattern of incision was a period of aggradation at U.S. Geological Survey gaging station 08096500 Brazos River at Waco, Texas, during the late 1920s and 1930s, probably associated with upstream dam construction. Lateral channel migration rates along the Brazos River determined from aerial photographs are greatest between Waco and Hempstead, Texas, with numerous bends moving an average of more than 10 feet per year. Migration rates at selected bends downstream from Hempstead were measured as less than 10 feet per year, on average. Two tributaries of the Brazos River, the Little and Navasota Rivers, also were investigated for historical channel adjustment. The Little River near Cameron, Texas (08106500) has incised its channel bed about 12 feet since 1949, and the lower Navasota River shows complex adjustment to bridge construction activities and a channel avulsion.
Effects of slope smoothing in river channel modeling

NASA Astrophysics Data System (ADS)

Kim, Kyungmin; Liu, Frank; Hodges, Ben R.

2017-04-01

In extending dynamic river modeling with the 1D Saint-Venant equations from a single reach to a large watershed there are critical questions as to how much bathymetric knowledge is necessary and how it should be represented parsimoniously. The ideal model will include the detail necessary to provide realism, but not include extraneous detail that should not exert a control on a 1D (cross-section averaged) solution. In a Saint-Venant model, the overall complexity of the river channel morphometry is typically abstracted into metrics for the channel slope, cross-sectional area, hydraulic radius, and roughness. In stream segments where cross-section surveys are closely spaced, it is not uncommon to have sharp changes in slope or even negative values (where a positive slope is the downstream direction). However, solving river flow with the Saint-Venant equations requires a degree of smoothness in the equation parameters or the equation set with the directly measured channel slopes may not be Lipschitz continuous. The results of non-smoothness are typically extended computational time to converge solutions (or complete failure to converge) and/or numerical instabilities under transient conditions. We have investigated using cubic splines to smooth the bottom slope and ensure always positive reference slopes within a 1D model. This method has been implemented in the Simulation Program for River Networks (SPRNT) and is compared to the standard HEC-RAS river solver. It is shown that the reformulation of the reference slope is both in keeping with the underlying derivation of the Saint-Venant equations and provides practical numerical stability without altering the realism of the simulation. This research was supported in part by the National Science Foundation under grant number CCF-1331610.
Water-quality data for the Ohio River from New Cumberland Dam to Pike Island Dam, West Virginia and Ohio, June-November 1992

USGS Publications Warehouse

Miller, Kimberly F.; Faulkenburg, C.W.; Chambers, D.B.; Waldron, M.C.

1995-01-01

This report contains water-quality data for the Ohio River, collected during the summer and fall of 1992, from river mile 51.1 (3.3 miles upstream from New Cumberland Dam) to river mile 84.0 (0.2 miles upstream from Pike Island Dam). The data were collected to assess the effects of hydropower development on water quality. Water quality was determined by a combination of repeated synoptic field measurements and laboratory analyses. Synoptic measurements were made along a longitudinal transect with 18 mid-channel sampling sites; cross-sectional transects of water quality were measured at 5 of these sites. Water-quality measurements also were made at two sites located on the back-channel (Ohio) side of Browns Island. Water temperature, dissolved oxygen concentration, pH, and specific conductance were measured at each longitudinal-transect and back-channel sampling site. Longitudinal-transect and back-channel stations were sampled at three depths (about 3.3 feet below the surface of the water, middle of the water column, and near the bottom of the river). Cross-sectional transects consisted of three or four detailed vertical pro- files of the same characteristics. Water samples were collected from three depths at the mid-channel vertical profile in each cross-sectional transect and were analyzed for concentrations of phyto- plankton photosynthetic pigments chlorophyll a and chlorophyll b. Estimates of the depth of light penetration (Secchi disk transparency) were made at pigment-sampling locations whenever light and river-surface conditions were appropriate. Synoptic sampling usually was completed in 12 hours or less and was repeated seven times between June 25 and November 6, 1992.
Streambank Protection and Erosion Control.

DTIC Science & Technology

1987-01-01

TABLE OF CONTENTS N CHAPTER ONE - INTRODUCTION ----------------------------------------- -- 1. 1.1 Purpose...downstream cross sectional area by stream bank erosion and bed scour to accommodate the increased flow. This may be caused by poor planning and assessment...the magnitude, except for very large floods which occur infrequently. 3.2 Channel Geometry [6] .*. Channel geometry of a river cross section is an
The effects of the Chesapeake Bay impact crater on the geologic framework and the correlation of hydrogeologic units of southeastern Virginia, south of the James River

USGS Publications Warehouse

Powars, David S.

2000-01-01

About 35 million years ago, a large comet or meteor slammed into the shallow shelf on the western margin of the Atlantic Ocean, creating the Chesapeake Bay impact crater. This report, the second in a series, refines the geologic framework of southeastern Virginia, south of the James River in and near the impact crater, and presents evidence for the existence of a pre-impact James River structural zone. The report includes detailed correlations of core lithologies with borehole geophysical logs; the correlations provide the foundation for the compilation of stratigraphic cross sections. These cross sections are tied into the geologic framework of the lower York-James Peninsula as presented in the first report in the series, Professional Paper 1612
Streamflow and sediment-transport data, Colorado River and three tributaries in Grand Canyon, Arizona, 1983 and 1985-86

USGS Publications Warehouse

Garrett, W.B.; van de Vanter, E.K.; Graf, J.B.

1993-01-01

The U.S. Geological Survey collected streamflow and sediment-transport data at 5 streamflow-gaging stations on the Colorado River between Glen Canyon Dam and Lake Mead as a part of an interagency environmental study. The data were collected for about 6 mo in 1983 and about 4 mo in 1985-86; data also were collected at 3 sites on tributary streams in 1983. The data were used for development of unsteady flow-routing and sediment-transport models, sand-load rating curves, and evaluation of channel changes. For the 1983 sampling period, 1,076 composite cross-section suspended-sediment samples were analyzed; 809 of these samples were collected on the main stem of the Colorado River and 267 samples were from the tributaries. Bed-material samples were obtained at 1,988 verticals; 161 samples of material in transport near the bed (bedload) were collected to define the location of sand, gravel, and bed rock in the channel cross section; and 664 discharge measurements were made. For the 1985-86 sampling period, 765 composite cross-section suspended-sediment samples and 887 individual vertical samples from cross sections were analyzed. Bed-material samples were obtained at 531 verticals, 159 samples of bedload were collected, and 218 discharge measurements were made. All data are presented in tabular form. Some types of data also are presented in graphs to better show trends or variations. (USGS)
A comprehensive one-dimensional numerical model for solute transport in rivers

NASA Astrophysics Data System (ADS)

Barati Moghaddam, Maryam; Mazaheri, Mehdi; MohammadVali Samani, Jamal

2017-01-01

One of the mechanisms that greatly affect the pollutant transport in rivers, especially in mountain streams, is the effect of transient storage zones. The main effect of these zones is to retain pollutants temporarily and then release them gradually. Transient storage zones indirectly influence all phenomena related to mass transport in rivers. This paper presents the TOASTS (third-order accuracy simulation of transient storage) model to simulate 1-D pollutant transport in rivers with irregular cross-sections under unsteady flow and transient storage zones. The proposed model was verified versus some analytical solutions and a 2-D hydrodynamic model. In addition, in order to demonstrate the model applicability, two hypothetical examples were designed and four sets of well-established frequently cited tracer study data were used. These cases cover different processes governing transport, cross-section types and flow regimes. The results of the TOASTS model, in comparison with two common contaminant transport models, shows better accuracy and numerical stability.
Tropical storm Irene flood of August 2011 in northwestern Massachusetts

USGS Publications Warehouse

Bent, Gardner C.; Olson, Scott A.; Massey, Andrew J.

2016-09-02

The simulated 1-percent AEP discharge water-surface elevations (nonregulatory) from recent (2015–16) hydraulic models for river reaches in the study area, which include the Deerfield, Green, and North Rivers in the Deerfield River Basin and the Hoosic River in the Hoosic River Basin, were compared with water-surface profiles in the FISs. The water-surface elevation comparisons were generally done downstream and upstream from bridges, dams, and major tributaries. The simulated 1-percent AEP discharge water-surface elevations of the recent hydraulic studies averaged 2.2, 2.3, 0.3, and 0.7 ft higher than water-surface elevations in the FISs for the Deerfield, Green, North, and Hoosic Rivers, respectively. The differences in water-surface elevations between the recent (2015–16) hydraulic studies and the FISs likely are because of (1) improved land elevation data from light detection and ranging (lidar) data collected in 2012, (2) detailed surveying of hydraulic structures and cross sections throughout the river reaches in 2012–13 (reflecting structure and cross section changes during the last 30–35 years), (3) updated hydrology analyses (30–35 water years of additional peak flow data at streamgages), and (4) high-water marks from the 2011 tropical storm Irene flood being used for model calibration.
Sele coastal plain flood risk due to wave storm and river flow interaction

NASA Astrophysics Data System (ADS)

Benassai, Guido; Aucelli, Pietro; Di Paola, Gianluigi; Della Morte, Renata; Cozzolino, Luca; Rizzo, Angela

2016-04-01

Wind waves, elevated water levels and river discharge can cause flooding in low-lying coastal areas, where the water level is the interaction between wave storm elevated water levels and river flow interaction. The factors driving the potential flood risk include weather conditions, river water stage and storm surge. These data are required to obtain inputs to run the hydrological model used to evaluate the water surface level during ordinary and extreme events regarding both the fluvial overflow and storm surge at the river mouth. In this paper we studied the interaction between the sea level variation and the river hydraulics in order to assess the location of the river floods in the Sele coastal plain. The wave data were acquired from the wave buoy of Ponza, while the water level data needed to assess the sea level variation were recorded by the tide gauge of Salerno. The water stages, river discharges and rating curves for Sele river were provided by Italian Hydrographic Service (Servizio Idrografico e Mareografico Nazionale, SIMN).We used the dataset of Albanella station (40°29'34.30"N, 15°00'44.30"E), located around 7 km from the river mouth. The extreme river discharges were evaluated through the Weibull equation, which were associated with their return period (TR). The steady state river water levels were evaluated through HEC-RAS 4.0 model, developed by Hydrologic Engineering Center (HEC) of the United States Army Corps of Engineers Hydrologic Engineering Center (USACE,2006). It is a well-known 1D model that computes water surface elevation (WSE) and velocity at discrete cross-sections by solving continuity, energy and flow resistance (e.g., Manning) equation. Data requirements for HEC-RAS include topographic information in the form of a series of cross-sections, friction parameter in the form of Manning's n values across each cross-section, and flow data including flow rates, flow change locations, and boundary conditions. For a steady state sub-critical simulation, the boundary condition is a known downstream WSE, in this case the elevated water level due to wave setup, wind setup and inverted barometer, while the upstream boundary condition consisted in WSE corresponding to river discharges associated to different return periods. The results of the simulations evidence, for the last 10 kilometers of the river, the burst of critical inundation scenarios even with moderate flow discharge, if associated with concurrent storm surge which increase the water level at the river mouth, obstructing normal flow discharge.
Dye-dispersion study at proposed pumped-storage project on Hudson River at Cornwall, New York

USGS Publications Warehouse

Dunn, Bernard; Gravlee, George C.

1978-01-01

Data were collected during a dye-dispersion study on a 6-mile, tide-affected reach of the Hudson River near the proposed Cornwall Pumped Storage Project on September 21-22, 1977. The results indicated that complete mixing did not occur during the first tidal cycle but was complete after two or more cycles. The fluorometric dye-tracing procedure was used to determine the dispersion characteristics of the water mass. Rhodamine WT dye, 20-percent solution, was continuously injected on the west side of the river throughout an ebb tide, and its movement was monitored during a 30-hour period. Samples were collected both individually and continuously. Automatic dye samplers were used at selected cross sections near each bank. Bathymetric measurements were made at eight cross sections between Newburgh and West Point to determine the depths. (Woodard-USGS)
Map showing contours on top of the upper Cretaceous Mowry Shale, Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Crysdale, B.L.

1991-01-01

This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 4,926 of these wells that penetrate the Minnelusa Formation and equivalents.
Map showing structure contours on the top of the upper Jurassic Morrison Formation, Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Crysdale, B.L.

1991-01-01

This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 2,429 of these wells that penetrate the Minnelusa Formation and equivalents.

Morphological changes of Gumara River channel over 50 years, upper Blue Nile basin, Ethiopia

NASA Astrophysics Data System (ADS)

Abate, Mengiste; Nyssen, Jan; Steenhuis, Tammo S.; Moges, Michael M.; Tilahun, Seifu A.; Enku, Temesgen; Adgo, Enyew

2015-06-01

In response to anthropogenic disturbances, alluvial rivers adjust their geometry. The alluvial river channels in the upper Blue Nile basin have been disturbed by human-induced factors since a longtime. This paper examines channel adjustment along a 38-km stretch of the Gumara River which drains towards Lake Tana and then to the Blue Nile. Over a 50 years period, agriculture developed rapidly in the catchment and flooding of the alluvial plain has become more frequent in recent times. The objectives of this study were to document the changes in channel planform and cross-section of the Gumara River and to investigate whether the changes could have contributed to the frequent flooding or vice versa. Two sets of aerial photographs (1957 and 1980) were scanned, and then orthorectified. Recent channel planform information was extracted from SPOT images of 2006 and Google Earth. Channel planform and bed morphology (vertical changes) were determined for these nearly 50 years period. The vertical changes were determined based on aggradation along a permanent structure, historic information on river cross-sections at a hydrological gauging station, and field observations. The results indicate that the lower reach of Gumara near its mouth has undergone major planform changes. A delta with approx. 1.12 km2 of emerged land was created between 1957 and 1980 and an additional 1 km2 of land has been added between 1980 and 2006. The sinuosity of the river changed only slightly: negatively (-1.1% i.e. meandering decreased) for the period from 1957 to 1980 and positively (+3.0%) for the period 1980-2006. Comparison of cross-sections at the hydrological gauging station showed that the deepest point in the river bed aggraded by 2.91 m for the period 1963-2009. The importance of sediment deposition in the stream and on its banks is related to land degradation in the upper catchment, and to artificial rising of Lake Tana level that creates a backwater effect and sediment deposition in Gumara River. Direct anthropogenic impacts (irrigation activities and building of dykes along the river banks) have contributed to the huge deposition in the river bed. Where the abstraction of water for irrigation is intensive, seepage water through the banks has contributed to river bank failure. In general, this study showed that changes to the planform at the mouth of the river and to the riverbed level are substantial. Moreover, the study indicated that the flood carrying capacity of the Gumara River channel has diminished in recent times.
Data for calibrating unsteady-flow sediment-transport models, East Fork River, Wyoming, 1975

USGS Publications Warehouse

Mahoney, Holly A.; Andrews, Edmund D.; Emmett, William W.; Leopold, Luna Bergere; Meade, Robert H.; Myrick, Robert M.; Nordin, Carl F.

1976-01-01

In 1975, data to calibrate a one-dimensional unsteady-flow and sediment-transport routing model were collected on a reach of the East Fork River of western Wyoming. The reach, 3.1 miles (5 kilometers) in length, wan immediately upstream from a previously established bedload sampling station. Nineteen channel cross sections were sounded at regular intervals during the spring-runoff period. Four stage recorders provided continuous records of water-surface elevations. Samples of bed material at most of the cross sections were obtained prior to high water. Streamflow and sediment-discharge measurements were collected at four of the sections.The physiography and hydrology of the contributing watershed, the study reach, and the equipment and techniques used in data collection are described briefly. The bulk of the report is a presentation of data for the several-week period of late May to early June 1975, for which concurrent water discharge data, bedload transport and size data, and cross-section depth measurements were collected. In addition, some data collected in 1973 and 1974 and before and after the calibration period in 1975 are included for completeness.
Preliminary cross section of Englebright Lake sediments

USGS Publications Warehouse

Snyder, Noah P.; Hampton, Margaret A.

2003-01-01

Overview -- The Upper Yuba River Studies Program is a CALFED-funded, multidisciplinary investigation of the feasibility of introducing anadromous fish species to the Yuba River system upstream of Englebright Dam. Englebright Lake (Figure 1 on poster) is a narrow, 14-km-long reservoir located in the northern Sierra Nevada, northeast of Marysville, CA. The dam was completed in 1941 for the primary purpose of trapping sediment derived from mining operations in the Yuba River watershed. Possible management scenarios include lowering or removing Englebright Dam, which could cause the release of stored sediments and associated contaminants, such as mercury used extensively in 19th-century hydraulic gold mining. Transport of released sediment to downstream areas could increase existing problems including flooding and mercury bioaccumulation in sport fish. To characterize the extent, grain size, and chemistry of this sediment, a coring campaign was done in Englebright Lake in May and June 2002. More than twenty holes were drilled at 7 different locations along the longitudinal axis of the reservoir (Figure 4 on poster), recovering 6 complete sequences of post-reservoir deposition and progradation. Here, a longitudinal cross section of Englebright Lake is presented (Figure 5 on poster), including pre-dam and present-day topographic profiles, and sedimentologic sections for each coring site. This figure shows the deltaic form of the reservoir deposit, with a thick upper section consisting of sand and gravel overlying silt, a steep front, and a thinner lower section dominated by silt. The methodologies used to create the reservoir cross section are discussed in the lower part of this poster.
20. GEOLOGY, PLAN AND PROFILE, SHOWING LINED AND UNLINED SECTIONS, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. GEOLOGY, PLAN AND PROFILE, SHOWING LINED AND UNLINED SECTIONS, AND DETAILED TYPICAL CROSS SECTIONS. Leeds, Hill, Barnard & Jewett drawing, no number, revised 3-20-42. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA
Interpreting the cross-sectional flow field in a river bank based on a genetic-algorithm two-dimensional heat-transport method (GA-VS2DH)

NASA Astrophysics Data System (ADS)

Su, Xiaoru; Shu, Longcang; Chen, Xunhong; Lu, Chengpeng; Wen, Zhonghui

2016-12-01

Interactions between surface waters and groundwater are of great significance for evaluating water resources and protecting ecosystem health. Heat as a tracer method is widely used in determination of the interactive exchange with high precision, low cost and great convenience. The flow in a river-bank cross-section occurs in vertical and lateral directions. In order to depict the flow path and its spatial distribution in bank areas, a genetic algorithm (GA) two-dimensional (2-D) heat-transport nested-loop method for variably saturated sediments, GA-VS2DH, was developed based on Microsoft Visual Basic 6.0. VS2DH was applied to model a 2-D bank-water flow field and GA was used to calibrate the model automatically by minimizing the difference between observed and simulated temperatures in bank areas. A hypothetical model was developed to assess the reliability of GA-VS2DH in inverse modeling in a river-bank system. Some benchmark tests were conducted to recognize the capability of GA-VS2DH. The results indicated that the simulated seepage velocity and parameters associated with GA-VS2DH were acceptable and reliable. Then GA-VS2DH was applied to two field sites in China with different sedimentary materials, to verify the reliability of the method. GA-VS2DH could be applied in interpreting the cross-sectional 2-D water flow field. The estimates of horizontal hydraulic conductivity at the Dawen River and Qinhuai River sites are 1.317 and 0.015 m/day, which correspond to sand and clay sediment in the two sites, respectively.
Channel evolution of the Hatchie River near the U.S. Highway 51 crossing in Lauderdale and Tipton counties, West Tennessee

USGS Publications Warehouse

Bryan, B.A.

1989-01-01

An investigation was conducted to describe the channel cross-section evolution near the bridge crossing of the Hatchie River at U.S. Highway 51 in Lauderdale and Tipton Counties, in West Tennessee. The study also included velocity and discharge distributions near the bridge crossing, and definition of streamflow duration and flood frequencies at the bridge site and comparison of these statistics with flows prior to the bridge collapse. Cross-section measurements at the site indicated that the channel was widening at a rate of 0.8 ft/year from 1931 through about 1975. The channel bed was stable at an elevation of about 235 ft. Construction of a south bound bridge in 1974 and 1975 reduced the effective flow width from about 4,000 to about 1,000 ft. Data collected from 1975 to 1981 indicated that the channel bed degraded to an elevation of about 230 ft and the widening rate increased to about 4.5 ft/year. The channel bed returned to approximately the pre-construction elevation of 235 ft as channel width increased. The widening rate decreased to about 1.8 ft/year from 1981 through 1989. Channel-geometry data indicated that recent channel morphology changes along the toe of the right bank have resulted in continued bank undercutting and bank failure. Cross-section geometry and flow-velocity distributions from measurements made from April 6 through 10, 1989, indicate that there is a high-flow meander pattern through this river reach and that the bridges are located at the point where the current strikes the right bank. (USGS)
The Expression of Backwater Dynamics in the Morphology, Kinematics and Deposit Architecture of Fluvio-deltaic Channels

NASA Astrophysics Data System (ADS)

Fernandes, A. M.; Smith, V.

2017-12-01

A downstream reduction in bed material flux is associated with the backwater zone, where rivers in their terminal reaches deepen to respond to the sea-level in the receiving basin. This downstream change in sediment transport is reflected in: a) lateral channel mobility, and b) sedimentology and stratigraphic architecture of composite depositional bodies that are left behind. Here we draw comparisons between the Mississippi River and the Trinity River (TX), in terms of bar morphologies and composition, and lateral mobility of these rivers. Across the backwater transition, both rivers display a slight increase in lateral migration rates, followed by substantial decrease lateral migration in the terminal reaches. Both rivers also display predominantly symmetrical channel cross-sections, coincident with very small migration rates in the terminal reaches. We will discuss how the divergence in sediment transport flux across the backwater zone relates to the volume and shape of bank-attached bars, which in turn relates to the cross-sectional shapes of the channels as well as their lateral migrations rates, and ultimately defines the internal architecture of the composite channel deposits that result. Furthermore, we draw comparisons between the morphologies of bank-attached bars and channels in rivers and submarine channels to present insights into how the dominant mode of sediment transport in these different environments ultimately controls the morphologies and kinematics of these channels.
Modeling Water-Surface Elevations and Virtual Shorelines for the Colorado River in Grand Canyon, Arizona

USGS Publications Warehouse

Magirl, Christopher S.; Breedlove, Michael J.; Webb, Robert H.; Griffiths, Peter G.

2008-01-01

Using widely-available software intended for modeling rivers, a new one-dimensional hydraulic model was developed for the Colorado River through Grand Canyon from Lees Ferry to Diamond Creek. Solving one-dimensional equations of energy and continuity, the model predicts stage for a known steady-state discharge at specific locations, or cross sections, along the river corridor. This model uses 2,680 cross sections built with high-resolution digital topography of ground locations away from the river flowing at a discharge of 227 m3/s; synthetic bathymetry was created for topography submerged below the 227 m3/s water surface. The synthetic bathymetry was created by adjusting the water depth at each cross section up or down until the model?s predicted water-surface elevation closely matched a known water surface. This approach is unorthodox and offers a technique to construct one-dimensional hydraulic models of bedrock-controlled rivers where bathymetric data have not been collected. An analysis of this modeling approach shows that while effective in enabling a useful model, the synthetic bathymetry can differ from the actual bathymetry. The known water-surface profile was measured using elevation data collected in 2000 and 2002, and the model can simulate discharges up to 5,900 m3/s. In addition to the hydraulic model, GIS-based techniques were used to estimate virtual shorelines and construct inundation maps. The error of the hydraulic model in predicting stage is within 0.4 m for discharges less than 1,300 m3/s. Between 1,300-2,500 m3/s, the model accuracy is about 1.0 m, and for discharges between 2,500-5,900 m3/s, the model accuracy is on the order of 1.5 m. In the absence of large floods on the flow-regulated Colorado River in Grand Canyon, the new hydraulic model and the accompanying inundation maps are a useful resource for researchers interested in water depths, shorelines, and stage-discharge curves for flows within the river corridor with 2002 topographic conditions.
Water-quality data for the Ohio River from New Cumberland Dam to Pike Island Dam, West Virginia and Ohio, May-October 1993

USGS Publications Warehouse

Miller, K.F.; Messinger, Terence; Waldron, M.C.; Faulkenburg, C.W.

1996-01-01

This report contains water-quality data for the Ohio River from river mile 51.1 (3.3 miles upstream from New Cumberland Dam) to river mile 84.0 (0.2 miles upstream from Pike Island Dam) that were collected during the summer and fall of 1993. The data were collected to establish the water quality of the Ohio River and to use in assessing the proposed effects of hydropower development on the water quality of the Ohio River. Water quality was determined by a combination of repeated synoptic field measurements, continuous-record monitoring, and laboratory analyses. Synoptic measurements were made along a longitudinal transect with 18 mid-channel sampling sites; cross-sectional transects of water-quality measurements were made at 5 of these sites. Water-quality measurements also were made at two sites located on the back-channel (Ohio) side of Browns Island. At each longitudinal-transect and back-channel sampling site, measurements were made of specific conductance, pH, water temperature, and dissolved oxygen conentration. Longitudinal-transect and back-channel stations were sampled at four depths (at the surface, about 3.3 feet below the surface, middle of the water column, and near the bottom of the river). Cross-sectional transects consisted of three to four detailed vertical profiles of the same characteristics. Water samples were collected from three depths at the mid-channel vertical profile in each cross-sectional transect and were analyzed for concentrations of phytoplankton photosynthetic pigments chlorophyll a and chlorophyll b. Estimates of the depth of light penetration (Secchi-disk transparency) were made at pigment-sampling locations whenever light and river-surface conditions were appropriate. Synoptic sampling usually was completed in 12 hours or less and was repeated 10 times from May through October 1993. Continuous-record monitoring of water quality consisted of hourly measurements of specific conductance, pH, water temperature, and dissolved oxygen concentration, made at a depth of 6.6 feet upstream and downstream of New Cumberland Dam. Continuous monitors were operated from May through October 1993.
Water-quality data for the Ohio River from Willow Island Dam to Belleville Dam, West Virginia and Ohio, May-October 1993

USGS Publications Warehouse

Miller, K.F.

1996-01-01

This report contains water-quality data for the Ohio River from river mile 160.6 (1.1 mile upstream from Willow Island Dam) to river mile 203.6 (0.3 mile upstream from Belleville Dam) that were collected during the summer and fall of 1993. The data were collected to establish the water quality of the Ohio River and to use in assessing the proposed effects of hydropower development on the water quality of the Ohio River. Water quality was monitored by a combination of synoptic field measurements, laboratory analyses, and continuous- record monitoring. Field measurements of water- quality characteristics were made along a longitudinal transect with 24 mid-channel sampling sites; cross-sectional transects of water-quality measurements were made at six of these sites. Water-quality measurements also were made at six sites located on the back-channel (West Virginia) sides of Marietta, Muskingum, and Blennerhassett Islands. At each longitudinal-transect and back- channel sampling site, measurements of specific conductance, pH, water temperature, and dissolved oxygen concentration were made at three depths (about 3.3 feet below the surface of the water, middle of the water column, and near the bottom of the river). Cross-sectional transects consisted of three to four detailed vertical profiles of the same characteristics. Water samples were collected at three depths in the mid-channel vertical profile in each cross-sectional transect and were analyzed for concentrations of phytoplankton chlorophyll a and chlorophyll b. Estimates of the depth of light penetration (Secchi disk transparency) were made at phytoplankton- pigment-sampling locations whenever light and river-surface conditions were appropriate. Each synoptic sampling event was completed in 2 days or less. The entire network was sampled 10 times from May 24 to October 27, 1993. Continuous-record monitoring of water quality consisted of hourly measurments of specific conductance, pH, water temperature, and dissolved oxygen concentration that were made at a depth of 6.6 feet at the ends of the upstream and downstream wingwalls at Willow Island Dam. Continuous-record monitors were operated from May through October 1993.
Bulb-T beams with self-consolidating concrete on the Route 33 bridge over the Pamunkey River in Virginia.

DOT National Transportation Integrated Search

2008-01-01

This study evaluated the bulb-T beams made with self-consolidating concrete (SCC) used in the Route 33 Bridge over the Pamunkey River at West Point, Virginia. Before the construction of the bridge, two test beams with SCC similar in cross section to ...
Ground-penetrating radar methods used in surface-water discharge measurements

USGS Publications Warehouse

Haeni, F.P.; Buursink, Marc L.; Costa, John E.; Melcher, Nick B.; Cheng, Ralph T.; Plant, William J.

2000-01-01

In 1999, an experiment was conducted to see if a combination of complementary radar methods could be used to calculate the discharge of a river without having any of the measuring equipment in the water. The cross-sectional area of the 183-meter wide Skagit River in Washington State was measured using a ground-penetrating radar (GPR) system with a single 100-MHz antenna. A van-mounted, side-looking pulsed-Doppler radar system was used to collect water-surface velocity data across the same section of the river. The combined radar data sets were used to calculate the river discharge and the results compared closely to the discharge measurement made by using the standard in-water measurement techniques.
Geomorphic change on the Missouri River during the flood of 2011: Chapter I in 2011 Floods of the Central United States

USGS Publications Warehouse

Schenk, Edward R.; Skalak, Katherine J.; Benthem, Adam J.; Dietsch, Benjamin J.; Woodward, Brenda K.; Wiche, Gregg J.; Galloway, Joel M.; Nustad, Rochelle A.; Hupp, Cliff R.

2014-01-01

The 2011 flood on the Missouri River was one of the largest floods since the river became regulated by a series of high dams in the mid-20th century (greater than 150,000 cubic feet per second during the peak). The flood persisted through most of the summer, eroding river banks, adding sand to sandbars, and moving the thalweg of the channel in many places. The U.S. Geological Survey monitored and assessed the changes in two reaches of the Missouri River: the Garrison Reach in North Dakota, bounded by the Garrison Dam and the Lake Oahe Reservoir, and the Recreational Reach along the boundary of South Dakota and Nebraska bounded upstream by the Gavins Point Dam and extending downstream from Ponca, Nebraska. Historical cross-section data from the Garrison Dam closure until immediately before the flood indicate that the upper reaches of the river near the dam experienced rapid erosion, channel incision, and island/sandbar loss following the dam closure. The erosion, incision, and land loss lessened with time. Conversely, the lower reach near the Lake Oahe Reservoir slackwaters became depositional with channel in-filling and sandbar growth through time as the flow slowed upon reaching the reservoir. Preliminary post-flood results in the Garrison Reach indicate that the main channel has deepened at most cross-sections whereas sandbars and islands have grown vertically. Sandbars and the thalweg migrated within the Recreational Reach, however net scouring and aggradation was minimal. Changes in the two-dimensional area of sandbars and islands are still being assessed using high-resolution satellite imagery. A sediment balance can be constructed for the Garrison Reach using cross-sections, bathymetric data, sand traps for wind-blown material, a quasi-three-dimensional numerical model, and dating of sediment cores. Data collection and analysis for a reach-scale sediment balance and a concurrent analysis of the effects of riparian and island vegetation on sediment deposition currently (2014) is ongoing.
JPRS Report Science & Technology Japan

DTIC Science & Technology

1989-10-20

plant callus o Adaptation of protozoans to microgravity o Fertilization and embryogeny of newt in space o Fertilization and embryogeny of sea urchin ...for by the mining and manufacturing branch. Moreover, about 50 percent of the energy consumed is exhausted to air, river, sea , etc., as waste heat...Cross section of substrate Figure 6. Photo of Cross Section of Coating Film Taken by Scanning Electron Microscope ( SEM ) It was heated for 60 hours
Water-surface profile and flood boundaries for the computed 100-year flood, lower Salt River, Lincoln County, Wyoming

USGS Publications Warehouse

Miller, Kirk A.; Mason, John P.

2000-01-01

The water-surface profile and flood boundaries for the computed 100-year flood were determined for a part of the lower Salt River in Lincoln County, Wyoming. Channel cross-section data were provided by Lincoln County. Cross-section data for bridges and other structures were collected and compiled by the U.S. Geological Survey. Roughness coefficients ranged from 0.034 to 0.100. The 100-year flood was computed using standard methods, ranged from 5,170 to 4,120 cubic feet per second through the study reach, and was adjusted proportional to contributing drainage area. Water-surface elevations were determined by the standard step-backwater method. Flood boundaries were plotted on digital basemaps.
Bed-material entrainment potential, Roaring Fork River at Basalt, Colorado

USGS Publications Warehouse

Elliott, John G.

2002-01-01

The Roaring Fork River at Basalt, Colorado, has a frequently mobile streambed composed of gravel, cobbles, and boulders. Recent urban and highway development on the flood plain, earlier attempts to realign and confine the channel, and flow obstructions such as bridge openings and piers have altered the hydrology, hydraulics, sediment transport, and sediment deposition areas of the Roaring Fork. Entrainment and deposition of coarse sediment on the streambed and in large alluvial bars have reduced the flood-conveying capacity of the river. Previous engineering studies have identified flood-prone areas and hazards related to inundation and high streamflow velocity, but those studies have not evaluated the potential response of the channel to discharges that entrain the coarse streambed. This study builds upon the results of earlier flood studies and identifies some potential areas of concern associated with bed-material entrainment. Cross-section surveys and simulated water-surface elevations from a previously run HEC?RAS model were used to calculate the boundary shear stress on the mean streambed, in the thalweg, and on the tops of adjacent alluvial bars for four reference streamflows. Sediment-size characteristics were determined for surficial material on the streambed, on large alluvial bars, and on a streambank. The median particle size (d50) for the streambed samples was 165 millimeters and for the alluvial bars and bank samples was 107 millimeters. Shear stresses generated by the 10-, 50-, and 100-year floods, and by a more common flow that just inundated most of the alluvial bars in the study reach were calculated at 14 of the cross sections used in the Roaring Fork River HEC?RAS model. The Shields equation was used with a Shields parameter of 0.030 to estimate the critical shear stress for entrainment of the median sediment particle size on the mean streambed, in the thalweg, and on adjacent alluvial bar surfaces at the 14 cross sections. Sediment-entrainment potential for a specific geomorphic surface was expressed as the ratio of the flood-generated boundary shear stress to the critical shear stress (to/tc) with respect to two threshold conditions. The partial entrainment threshold (to/tc=1) is the condition where the mean boundary shear stress (to) equals the critical shear stress for the median particle size (tc) at that cross section. At this threshold discharge, the d50 particle size becomes entrained, but movement of d50-size particles may be limited to a few individual particles or in a small area of the streambed surface. The complete entrainment threshold (to/tc=2) is the condition where to is twice the critical shear stress for the median particle size, the condition where complete or widespread mobilization of the d50 particle-size fraction is anticipated. Entrainment potential for a specific reference streamflow varied greatly in the downstream direction. At some cross sections, the bed or bar material was mobile, whereas at other cross sections, the bed or bar material was immobile for the same discharge. The significance of downstream variability is that sediment entrained at one cross section may be transported into, but not through, a cross section farther downstream, a situation resulting in sediment deposition and possibly progressive aggradation and loss of channel conveyance. Little or no sediment in the d50-size range is likely to be entrained or transported through much of the study reach by the bar-inundating streamflow. However, the entrainment potential at this discharge increases abruptly to more than twice the critical value, then decreases abruptly, at a series of cross sections located downstream from the Emma and Midland Avenue Bridges. Median particle-size sediment is mobile at most cross sections in the study reach during the 10-year flood; however, the bed material is immobile at cross sections just upstream from the Upper Bypass and Midland Avenue Bridges. A similar s
Spillway for Benbrook Dam, Clear Fork of the Trinity River, Texas: Model Investigation

DTIC Science & Technology

1949-03-01

section at tho too of tho spillway to tho trapezoidal cross section of tho exit channel. Concreto training walls 11 ft in height will confine the...embankment sections to the spillway, thus eliminating the concreto sec- tiona . This procedure would require training walls at each abutment t o protect
Development of a cross-section based stream package for MODFLOW

NASA Astrophysics Data System (ADS)

Ou, G.; Chen, X.; Irmak, A.

2012-12-01

Accurate simulation of stream-aquifer interactions for wide rivers using the streamflow routing package in MODFLOW is very challenging. To better represent a wide river spanning over multiple model grid cells, a Cross-Section based streamflow Routing (CSR) package is developed and incorporated into MODFLOW to simulate the interaction between streams and aquifers. In the CSR package, a stream segment is represented as a four-point polygon instead of a polyline which is traditionally used in streamflow routing simulation. Each stream segment is composed of upstream and downstream cross-sections. A cross-section consists of a number of streambed points possessing coordinates, streambed thicknesses and streambed hydraulic conductivities to describe the streambed geometry and hydraulic properties. The left and right end points are used to determine the locations of the stream segments. According to the cross-section geometry and hydraulic properties, CSR calculates the new stream stage at the cross-section using the Brent's method to solve the Manning's Equation. A module is developed to automatically compute the area of the stream segment polygon on each intersected MODFLOW grid cell as the upstream and downstream stages change. The stream stage and streambed hydraulic properties of model grids are interpolated based on the streambed points. Streambed leakage is computed as a function of streambed conductance and difference between the groundwater level and stream stage. The Muskingum-Cunge flow routing scheme with variable parameters is used to simulate the streamflow as the groundwater (discharge or recharge) contributes as lateral flows. An example is used to illustrate the capabilities of the CSR package. The result shows that the CSR is applicable to describing the spatial and temporal variation in the interaction between streams and aquifers. The input data become simple due to that the internal program automatically interpolates the cross-section data to each model grid cell.
Mapping the response of riparian vegetation to possible flow reductions in the Snake River, Idaho

USGS Publications Warehouse

Johnson, W. Carter; Dixon, Mark D.; Simons, Robert W.; Jenson, Susan; Larson, Kevin

1995-01-01

This study was initiated to determine the general effects of potential flow reductions in the middle Snake River (Swan Falls Dam downstream to the Idaho-Oregon border) on its riparian vegetation. Considerable water from the river is currently used to irrigate the adjacent Snake River Plain, and increased demand for water in the future is likely. The problem was subdivided into several research components including: field investigation of the existing riparian vegetation and river environment, hydrological modeling to calculate the effects of one flow scenario on hydrological regime, and integration of vegetation and hydrological modeling results with a Geographic Information System (GIs) to map the riverbed, island, and bank conditions under the scenario flow. Field work was conducted in summer 1990. Riparian vegetation along 40 U.S. Geological Survey cross-sections was sampled at approximately 1.25 mile intervals within the 50 mile long study area. Cross-section and flow data were provided by the U.S. Geological. Survey. GIs mapping of land/water cover using ARC/INFO was based on 1987 aerial photographs. Riverbed contour maps were produced by linking cross-section data, topographic contouring software (anudem), and GIs. The maps were used to spatially display shallow areas in the channel likely to become vegetated under reduced flow conditions. The scenario would reduce flow by approximately 20% (160 MAF) and lower the river an average of 0.5 ft. The scenario flow could cause a drop in the elevation of the riparian zone comparable to the drop in mean river level and expansion of the lower riparian zone into shallow areas of the channel. The GIs maps showed that the shallow areas of the channel more likely to become vegetated under the scenario flow are located in wide reaches near islands. Some possible ecological consequences of the scenario flow include a greater area of riparian habitat, reduced flow velocity and sedimentation in shallow channels leading to channel deactivation, increased island visitation and nest predation by predatory mammals due to loss of a water barrier between some islands and banks, and larger populations of alien plant species in the new riparian vegetation.
Channel Width Change as a Potential Sediment Source, Minnesota River Basin

NASA Astrophysics Data System (ADS)

Lauer, J. W.; Echterling, C.; Lenhart, C. F.; Rausch, R.; Belmont, P.

2017-12-01

Turbidity and suspended sediment are important management considerations along the Minnesota River. The system has experience large and relatively consistent increases in both discharge and channel width over the past century. Here we consider the potential role of channel cross section enlargement as a sediment source. Reach-average channel width was digitized from aerial images dated between 1937 and 2015 along multiple sub-reaches of the Minnesota River and its major tributaries. Many of the sub-reaches include several actively migrating bends. The analysis shows relatively consistent increases in width over time, with average increase rates of 0.4 percent per year. Extrapolation to the river network using a regional relationship for cross-sectional area vs. drainage area indicates that large tributaries and main-stem reaches account for most of the bankfull cross-sectional volume in the basin. Larger tributaries and the main stem thus appear more important for widening related sediment production than small tributaries. On a basin-wide basis, widening could be responsible for a gross supply of more sediment than has been gaged at several main-stem sites, indicating that there may be important sinks for both sand and silt/clay size material distributed throughout the system. Sediment storage is probably largest along the lowest-slope reaches of the main stem. While channel width appears to have adjusted relatively quickly in response to discharge and other hydraulic modifications, net storage of sediment in floodplains probably occurs sufficiently slowly that depth adjustment will lag width adjustment significantly. Detailed analysis of the lower Minnesota River using a river segmenting approach allows for a more detailed assessment of reach-scale processes. Away from channel cutoffs, elongation of the channel at eroding bends is consistent with rates observed on other actively migrating rivers. However, the sinuosity increase has been more than compensated by several natural and engineered cutoffs. The sinuosity change away from cutoffs probably plays a relatively modest role in the reach's sediment budget. However, point bars and abandoned oxbow lakes are important zones of sediment storage that may be large enough to account for much of the widening-related production of sand in the reach.

River bed Elevation Changes and Increasing Flood Hazards in the Nisqually River at Mount Rainier National Park, Washington

NASA Astrophysics Data System (ADS)

Halmon, S.; Kennard, P.; Beason, S.; Beaulieu, E.; Mitchell, L.

2006-12-01

Mount Rainier, located in Southwestern Washington, is the most heavily glaciated volcano of the Cascade Mountain Range. Due to the large quantities of glaciers, Mount Rainier also has a large number of braided rivers, which are formed by a heavy sediment load being released from the glaciers. As sediment builds in the river, its bed increases, or aggrades,its floodplain changes. Some contributions to a river's increased sediment load are debris flows, erosion, and runoff, which tend to carry trees, boulders, and sediment downstream. Over a period of time, the increased sediment load will result in the river's rise in elevation. The purpose of this study is to monitor aggradation rates, which is an increase in height of the river bed, in one of Mount Rainier's major rivers, the Nisqually. The studied location is near employee offices and visitor attractions in Longmire. The results of this study will also provide support to decision makers regarding geological hazard reduction in the area. The Nisqually glacier is located on the southern side of the volcano, which receives a lot of sunlight, thus releasing large amounts of snowmelt and sediment in the summer. Historical data indicate that several current features which may contribute to future flooding, such as the unnatural uphill slope to the river, which is due to a major depositional event in the late 1700s where 15 ft of material was deposited in this area. Other current features are the glaciers surrounding the Nisqually glacier, such as the Van Trump and Kaultz glaciers that produced large outbursts, affecting the Nisqually River and the Longmire area in 2001, 2003, and 2005. In an effort to further explore these areas, the research team used a surveying device, total station, in the Nisqually River to measure elevation change and angles of various positions within ten cross sections along the Longmire area. This data was then put into GIS for analyzation of its current sediment level and for comparison to previous cross sections, which were in 1993 and 2005. Results of the data analysis revealed changes in altitude of the sediment, as well as new areas of built up sediment. For example, a 7 foot increase in elevation, which was not revealed in the 2005 data, indicated there was an increased amount of debris that traveled from upstream. Further data will be obtained once all the cross sections are completed and data is closer analyzed.
Do rivers really obey power-laws? Using continuous high resolution measurements to define bankfull channel and evaluate downstream hydraulic-scaling over large changes in drainage area

NASA Astrophysics Data System (ADS)

Scher, C.; Tennant, C.; Larsen, L.; Bellugi, D. G.

2016-12-01

Advances in remote-sensing technology allow for cost-effective, accurate, high-resolution mapping of river-channel topography and shallow aquatic bathymetry over large spatial scales. A combination of near-infrared and green spectra airborne laser swath mapping was used to map river channel bathymetry and watershed geometry over 90+ river-kilometers (75-1175 km2) of the Greys River in Wyoming. The day of flight wetted channel was identified from green LiDAR returns, and more than 1800 valley-bottom cross-sections were extracted at regular 50-m intervals. The bankfull channel geometry was identified using a "watershed-based" algorithm that incrementally filled local minima to a "spill" point, thereby constraining areas of local convergence and delineating all the potential channels along the cross-section for each distinct "spill stage." Multiple potential channels in alluvial floodplains and lack of clearly defined channel banks in bedrock reaches challenge identification of the bankfull channel based on topology alone. Here we combine a variety of topological measures, geometrical considerations, and stage levels to define a stage-dependent bankfull channel geometry, and compare the results with day of flight wetted channel data. Initial results suggest that channel hydraulic geometry and basin hydrology power-law scaling may not accurately capture downstream channel adjustments for rivers draining complex mountain topography.
Developing an Approach to Prioritize River Restoration using Data Extracted from Flood Risk Information System Databases.

NASA Astrophysics Data System (ADS)

Vimal, S.; Tarboton, D. G.; Band, L. E.; Duncan, J. M.; Lovette, J. P.; Corzo, G.; Miles, B.

2015-12-01

Prioritizing river restoration requires information on river geometry. In many states in the US detailed river geometry has been collected for floodplain mapping and is available in Flood Risk Information Systems (FRIS). In particular, North Carolina has, for its 100 Counties, developed a database of numerous HEC-RAS models which are available through its Flood Risk Information System (FRIS). These models that include over 260 variables were developed and updated by numerous contractors. They contain detailed surveyed or LiDAR derived cross-sections and modeled flood extents for different extreme event return periods. In this work, over 4700 HEC-RAS models' data was integrated and upscaled to utilize detailed cross-section information and 100-year modelled flood extent information to enable river restoration prioritization for the entire state of North Carolina. We developed procedures to extract geomorphic properties such as entrenchment ratio, incision ratio, etc. from these models. Entrenchment ratio quantifies the vertical containment of rivers and thereby their vulnerability to flooding and incision ratio quantifies the depth per unit width. A map of entrenchment ratio for the whole state was derived by linking these model results to a geodatabase. A ranking of highly entrenched counties enabling prioritization for flood allowance and mitigation was obtained. The results were shared through HydroShare and web maps developed for their visualization using Google Maps Engine API.
Isopach map of the interval from surface elevation to the top of the Pennsylvanian and Permian Minnelusa Formation and equivalents, Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Crysdale, B.L.

1990-01-01

This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 1,480 of these wells that penetrate the Minnelusa Formation and equivalents.
Map showing contours on the top of the Pennsylvanian and Permian Minnelusa Formation and equivalents, Powder River basin, Wyoming and Montana

USGS Publications Warehouse

Crysdale, B.L.

1990-01-01

This map is one in a series of U.S. Geological Survey Miscellaneous Field Studies (MF) maps showing computer-generated structure contours, isopachs, and cross sections of selected formations in the Powder River basin, Wyoming and Montana. The map and cross sections were constructed from information stored in a U.S. Geological Survey Evolution of Sedimentary Basins data base. This data base contains picks of geologic formation and (or) unit tops and bases determined from electric resistivity and gamma-ray logs of 8,592 wells penetrating Tertiary and older rocks in the Powder River basin. Well completion cards (scout tickets) were reviewed and compared with copies of all logs, and formation or unit contacts determined by N. M. Denson, D.L. Macke, R. R. Schumann and others. This isopach map is based on information from 1,480 of these wells that penetrate the Minnelusa Formation and equivalents.
An analysis of river bank slope and unsaturated flow effects on bank storage.

PubMed

Doble, Rebecca; Brunner, Philip; McCallum, James; Cook, Peter G

2012-01-01

Recognizing the underlying mechanisms of bank storage and return flow is important for understanding streamflow hydrographs. Analytical models have been widely used to estimate the impacts of bank storage, but are often based on assumptions of conditions that are rarely found in the field, such as vertical river banks and saturated flow. Numerical simulations of bank storage and return flow in river-aquifer cross sections with vertical and sloping banks were undertaken using a fully-coupled, surface-subsurface flow model. Sloping river banks were found to increase the bank infiltration rates by 98% and storage volume by 40% for a bank slope of 3.4° from horizontal, and for a slope of 8.5°, delay bank return flow by more than four times compared with vertical river banks and saturated flow. The results suggested that conventional analytical approximations cannot adequately be used to quantify bank storage when bank slope is less than 60° from horizontal. Additionally, in the unconfined aquifers modeled, the analytical solutions did not accurately model bank storage and return flow even in rivers with vertical banks due to a violation of the dupuit assumption. Bank storage and return flow were also modeled for more realistic cross sections and river hydrograph from the Fitzroy River, Western Australia, to indicate the importance of accurately modeling sloping river banks at a field scale. Following a single wet season flood event of 12 m, results showed that it may take over 3.5 years for 50% of the bank storage volume to return to the river. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.
Hydrodynamic and sedimentological controls governing formation of fluvial levees

NASA Astrophysics Data System (ADS)

Johnston, G. H.; Edmonds, D. A.; David, S. R.; Czuba, J. A.

2017-12-01

Fluvial levees are familiar features found on the margins of river channels, yet we know little about what controls their presence, height, and shape. These attributes of levees are important because they control sediment transfer from channel to floodplain and flooding patterns along a river system. Despite the familiarity and importance of levees, there is a surprising lack of basic geomorphic data on fluvial levees. Because of this we seek to understand: 1) where along rivers do levees tend to occur?; 2) what geomorphic and hydrodynamic variables control cross-sectional shape of levees? We address these questions by extracting levee shape from LiDAR data and by collecting hydrodynamic and sedimentological data from reaches of the Tippecanoe River, the White River, and the Muscatatuck River, Indiana, USA. Fluvial levees are extracted from a 1.5-m resolution LiDAR bare surface model and compared to hydrological, sedimentological, and geomorphological data from USGS stream gages. We digitized banklines and extracted levee cross-sections to calculate levee slope, taper, height, e-folding length, and e-folding width. To answer the research questions, we performed a multivariable regression between the independent variables—channel geometry, sediment grain size and concentration, flooding conditions, and slope—and the dependent levee variables. We find considerable variation in levee presence and shape in our field data. On the Muscatatuck River levees occur on 30% of the banks compared to 10% on the White River. Moreover, levees on the Muscatatuck are on average 3 times wider than the White River. This is consistent with the observation that the Muscatatuck is finer-grained compared to the White River and points to sedimentology being an important control on levee geomorphology. Future work includes building a morphodynamic model to understand how different hydrodynamic and geomorphic conditions control levee geometry.
Looking to the Future: Non-contact Methods for Measuring Streamflow

USGS Publications Warehouse

Costa, J.E.; Cheng, R.T.; Haeni, F.P.; Melcher, N.B.; Spicer, K.R.; Plant, J.; Keller, W.C.; Hayes, K.; Wahl, T.L.; Pugh, C.A.; Oberg, K.A.; Vermeyen, T.B.

2002-01-01

We have conducted a series of proof-of-concept experiments to demonstrate whether it is possible to make completely non-contact open-channel discharge measurements. After an extensive evaluation of potential technologies, we concluded a combination of high-frequency (microwave) radar (for measuring surface velocity) and low-frequency radar (ground-penetrating radar) for measuring channel cross-section, had the best chance for success. The first experiment in 1999 on the Skagit River, Washington, using non-contact methods, produced a discharge value nearly exactly the same as from an ADCP and current meter. Surface-velocity data were converted to mean velocity based on measurements of the velocity profile (multiplied by 0.85), and radar signal speed in impure fresh water was measured to be 0.11-0.12 ft/ns. The weak link was thought to be the requirement to suspend the GPR antenna over the water, which required a bridge or cableway. Two contractors, expert with radar, were unsuccessful in field experiments to measure channel cross-section from the riverbank. Another series of experiments were designed to demonstrate whether both radar systems could be mounted on a helicopter, flown back and forth across a river, and provide data to compute flow. In Sept. 2000 and May 2001, a series of helicopter flights with mounted radar systems successfully measured surface velocity and channel cross-section of the Cowlitz River, Washington.
Stratigraphic cross sections of the Niobrara interval of the Cody Shale and associated rocks in the Wind River Basin, central Wyoming

USGS Publications Warehouse

Finn, Thomas M.

2017-02-07

The Wind River Basin in Wyoming is one of many structural and sedimentary basins that formed in the Rocky Mountain foreland during the Laramide orogeny. The basin is nearly 200 miles long, 70 miles wide, and encompasses about 7,400 square miles in central Wyoming. The basin is bounded by the Washakie Range, Owl Creek uplift, and southern Bighorn Mountains on the north, the Casper arch on the east, the Granite Mountains on the south, and Wind River Range on the west.Many important conventional oil and gas fields producing from reservoirs ranging in age from Mississippian through Tertiary have been discovered in this basin. In addition, an extensive unconventional overpressured basin-centered gas accumulation has been identified in Cretaceous and Tertiary strata in the deeper parts of the basin. It has long been suggested that various Upper Cretaceous marine shales, including the Cody Shale, are the principal hydrocarbon source rocks for many of these accumulations. With recent advances and success in horizontal drilling and multistage fracture stimulation, there has been an increase in exploration and completion of wells in these marine shales in other Rocky Mountain Laramide basins that were traditionally thought of only as hydrocarbon source rocks.The two stratigraphic cross sections presented in this report were constructed as part of a project carried out by the U.S. Geological Survey to characterize and evaluate the undiscovered continuous (unconventional) oil and gas resources of the Niobrara interval of the Upper Cretaceous Cody Shale in the Wind River Basin in central Wyoming. The primary purpose of the cross sections is to show the stratigraphic relationship of the Niobrara equivalent strata and associated rocks in the lower part of the Cody Shale in the Wind River Basin. These two cross sections were constructed using borehole geophysical logs from 37 wells drilled for oil and gas exploration and production, and one surface section along East Sheep Creek near Shotgun Butte in the northwestern part of the basin. Both lines originate at the East Sheep Creek surface section and end near Clarkson Hill in the extreme southeastern part of the basin. The stratigraphic interval extends from the upper part of the Frontier Formation to the middle part of the Cody Shale. The datum is the base of the “chalk kick” marker bed, a distinctive resistivity peak or zone in the lower part of the Cody Shale. A gamma ray and (or) spontaneous potential (SP) log was used in combination with a resistivity log to identify and correlate units. Marine molluscan index fossils collected from nearby outcrop sections were projected into the subsurface to help determine the relative ages of the strata and aid in correlation.
Modern geomorphology in a post-glacial landscape and implications for river restoration, eastern Yosemite Valley, Yosemite National Park, USA

NASA Astrophysics Data System (ADS)

Minear, J. T.; Wright, S. A.; Roche, J. W.

2011-12-01

Yosemite National Park, USA, is one of the most popular national parks in the country with over 3.9 million visitors annually. The majority of tourists visit a relatively small area around the Merced River in scenic eastern Yosemite Valley, which has resulted in degradation to the river and streambanks. The National Park Service is updating the long-term management plan for the Merced River which includes river restoration. A key component determining the success of future river restoration efforts is the transport and supply of sediment. For this study, we investigate the modern geomorphology of the eastern Yosemite Valley region. For the watershed and reach analyses, we draw from a variety of topographic and hydrologic records, including 20-years of data from permanent cross sections, aerial and ground-based LiDAR surveys, and a nearly 100-year hydrologic record. In addition, we utilize hydraulic and sediment transport models to investigate channel velocities, bed shear stress and sediment transport at the reach scale. From the watershed-scale analysis, it is likely that large-scale remnant glacial features exert a primary control on the sediment supply to the study area with relatively small volumes of both suspended and bedload sediment being contributed to the study site. Two of the three major watersheds, Tenaya Creek and the upper Merced River, likely contribute only small amounts of bedload downstream due to low-gradient depositional reaches. Though little-known, the third major watershed, Illilouette Creek, is the only watershed capable of contributing larger amounts of bedload material, though the bedload material is likely contributed only during high flow events. High flows in the Yosemite Valley region have two different distributions: large early winter storm events above the 20-year return interval, and moderate snowmelt flows at and below the 20-year return interval. Sediment transport analyses indicate that bedload transport is dominated by relatively frequent (<2 year) snowmelt flow events and that the coarsest material in the reach (>110 mm) is mobile during these flows. The permanent cross sections record large topographic changes, including infilling at key bars, associated with the 1997 flood, the largest recorded early winter event (100-year return interval). Following snowmelt events post-1997, cross sections are returning to near pre-1997 levels. The cross section data suggest there is likely a disconnect between sediment supplied to the reach and sediment transport, with the majority of sediment supply occurring during large early winter events while the majority of sediment transport occurs during snowmelt events. An implication of our findings for river restoration in this area of the Merced River is that the ability of the channel to rebuild streambanks is relatively low, given the low suspended sediment supply. In contrast, bedload transport is relatively frequent and occurs in significant quantities, suggesting that river restoration involving bed recovery (e.g. recovery of pools formed by riprap or bridges) should be relatively rapid if obstructions are removed.
Reaction and relaxation in a coarse-grained fluvial system following catchment-wide disturbance

NASA Astrophysics Data System (ADS)

Tunnicliffe, Jon; Brierley, Gary; Fuller, Ian C.; Leenman, Anya; Marden, Mike; Peacock, Dave

2018-04-01

The Waiapu River catchment (drainage area of 1734-km2) is one of the most prolific conveyors of sediment in the world, annually delivering roughly 35 Mt of fine material to the ocean from eroding gullies, hillslopes, and reworked sediment on valley floors. Tectonic and geologic influences, in combination with a dynamic climate influenced by tropical cyclones and clearance of vegetation from steep hillslopes, predisposes this region to high rates of erosion. The bedload sediment regime of the river is strongly influenced by several exceptionally large gullies and gully complexes that produce a coarse-grained, poorly sorted sediment mixture. Rapid abrasion and breakdown leads to high rates of suspended sediment yield. A wave of bedload material, manifesting as elevated bed levels and significant widening of active alluvial fills, has been triggered by large inputs of hillslope material from a few key tributary catchments following Cyclone Bola in 1988. We review the evidence for the relaxation process of the sedimentary system in the subsequent 29 years, appraising some of the legacy effects that may endure, as associated with reworking of the considerable alluvial stores within the Waiapu system. We use Structure-from-Motion (SfM) techniques and archival aerial photos to quantify changes in sediment storage at the base of two major gully systems in recent decades. A record of over 850 cross section surveys at 62 sites on 10 rivers throughout the catchment (1958-2017) indicates recent transition from a trend of continuous accumulation to downcutting and remobilisation of valley-bottom deposits. The channel cross sections provide a minimum estimate of sediment flux from source areas to the lower reaches of the river, giving a rudimentary but spatially extensive picture of the wave of material cascading through the drainage network. The largest impacts occur in the upper steepland rivers, closest to the landslide-derived sediment supply. Transport rates here, as inferred from cross section change, are at a maximum during an aggradational phase following Cyclone Bola then taper off, despite the large sediment accumulations remaining in the system. As of 2017, the river is in the process of incising the upper extents of this deposit on a trajectory of recovery toward pre-Bola conditions. The compilation of cross section data provides us with new insights into the sensitivity of particular sites in the landscape, as well as the changing relationship between reach sediment storage and transport rates during the response and relaxation phase of a major disturbance in a large catchment.
Water-quality data for the Ohio River from Willow Island Dam to Belleville Dam, West Virginia and Ohio, June-October 1991

USGS Publications Warehouse

Chambers, D.B.; Miller, K.F.; Waldron, M.C.; Falkenburg, C.W.

1994-01-01

This report contains water-quality data for the Ohio River from river mile 160.6 (1.1 mi upstream from Willow Island Dam) to river mile 203.6 (0.3 mi upstream from Belleville Dam) during the summer of 1991. Water quality was determined by a combi- nation of synoptic field measurements and laboratory analyses. Synoptic sampling consisted of 8 cross-sectional transects and a longitudinal transect with 28 mid-channel stations. Each cross- sectional transect included five vertical profiles of water temperature, dissolved oxygen concen- tration, pH, and specific conductance. Longi- tudinal transect stations were sampled at three depths (near the surface, middle of the water column, and at or near the bottom) for the same characteristics. Sampling was completed in 3 days or less, and was repeated approximately every 2 weeks from June through October 1991. Beginning in August 1991, water samples were collected at selected locations and analyzed for chlorophyll-a and pheophytin concentrations, as measures of phytoplankton biomass and phytoplankton-degradation products, respectively. The depth of light penetration was estimated at all pigment-sampling locations.
Linking long-term gully and river channel dynamics to environmental change using repeat photography (Northern Ethiopia)

NASA Astrophysics Data System (ADS)

Frankl, Amaury; Nyssen, Jan; De Dapper, Morgan; Haile, Mitiku; Billi, Paolo; Munro, R. Neil; Deckers, Jozef; Poesen, Jean

2011-06-01

In the Highlands of Northern Ethiopia gully occurrence is linked to poverty-driven unsustainable use of the land in a vulnerable semi-arid and mountainous environment, where intensive rainfall challenges the physical integrity of the landscape. Trends in gully and river channel erosion, and their relation to triggering environmental changes can proffer valuable insights into sustainable development in Northern Ethiopia. In order to assess the region-wide change in gully and river channel morphology over 140 years, a set of 57 historical photographs taken in Tigray, and, clearly displaying gully cross-sections, were precisely repeated from 2006 till 2009. Ninety-two percent of the gully and river sections (n = 38) increased in cross-sectional area during the studied period, especially after 1975. Two repeatedly photographed catchments of Lake Ashenge and Atsela allowed a detailed study of gully development from 1936 until 2009. A conceptual hydrogeomorphic model was devised for these catchments and validated for the Northern Ethiopian Highlands. Three major phases can be distinguished in the hydrological regime of the catchments. In the first phase, between 1868 (or earlier) and ca. 1965, the relatively stable channels showed an oversized morphology inherited from a previous period when external forcing in environmental conditions had caused the channels to shape. In the second phase (ca. 1965 - ca. 2000), increased aridity and continued vegetation clearance accelerated the channel dynamics of the gully and river system. The third phase (ca. 2000 - present) started after the large-scale implementation of soil and water conservation measures. In 2009, 23% of the gully and river sections were stabilizing. This paper validates previous research indicating severe land degradation in the second half of the 20th century. Additionally, it demonstrates that the recent erosive cycle started around 1965 and, that at the present time, improved land management stabilizes headwater streams.
Fluvial development of the Nete valley during the Late Weichselian and early Holocene: new data from a cross-section south of Kasterlee (NE-Belgium)

NASA Astrophysics Data System (ADS)

Beerten, Koen; Van Nieuland, Jasper; Vandenberghe, Dimitri; Deforce, Koen; Rogiers, Bart

2014-05-01

The Late Quaternary geomorphology and stratigraphy of the fluvial deposits in the Kleine Nete valley is poorly documented, apart from the classic paper by Munaut and Paulissen (1973) on the palaeo-ecology of this river valley. A good description of the fluvial development within this catchment over longer timescales would help to understand palaeohydrological conditions, as it may give insight into changes in river bed elevation and palaeo-channel morphology. As such, existing hydrological models can be tested for conditions that are different than today, by unlocking the palaeohydrological archive. During road construction works, a cross-section through the Kleine Nete alluvium could be observed, directly (tens of meters) south of the present river course and underneath an abandoned channel that is traceable on historical maps and still visible in the landscape today. The river's alluvium is very thin - the sediment thickness usually does not exceed 2-3 m - while the composition is monotonous, either sand or peat with at a thin loamy layer at the top. Different fluvial facies, including horizontally laminated and cross-bedded sands, channel-fill sands, in-situ (?) peat layers, reworked peat mixed with sand, and loamy alluvium were encountered and sampled for grain-size analysis, palynological analysis and optically stimulated luminescence (OSL) dating. The preliminary results show that vertical aggradation took place during the late Pleniglacial (between ca. 20-16 ka) over a large area (probably by a braided river). This aggradation phase was followed by incision and the development of confined channels that subsequently were filled with basal peat and channel sands during the Late Glacial (ca. 15-12 ka) and the early Holocene (ca. 11 ka). The different dimensions of the observed channels (cross-section and river bed elevation), in comparison with those of the present-day river, suggest that large parts of the alluvial plain were experiencing different hydrological conditions during the Late Glacial and early Holocene than today. We conclude that despite the non-continuous nature of the sedimentary archive in the investigated profile, relevant information with respect to the palaeohydrological evolution of the Nete catchment could be obtained. Reference Munaut, A.V., Paulissen, E., 1973. Evolution et paléo-écologie de la vallée de la Petite Nèthe au cours du post-Würm (Belgique). Extrait des Annales de la Société Géologique de Belgique 96, 301-346.
An Equivalent cross-section Framework for improving computational efficiency in Distributed Hydrologic Modelling

NASA Astrophysics Data System (ADS)

Khan, Urooj; Tuteja, Narendra; Ajami, Hoori; Sharma, Ashish

2014-05-01

While the potential uses and benefits of distributed catchment simulation models is undeniable, their practical usage is often hindered by the computational resources they demand. To reduce the computational time/effort in distributed hydrological modelling, a new approach of modelling over an equivalent cross-section is investigated where topographical and physiographic properties of first-order sub-basins are aggregated to constitute modelling elements. To formulate an equivalent cross-section, a homogenization test is conducted to assess the loss in accuracy when averaging topographic and physiographic variables, i.e. length, slope, soil depth and soil type. The homogenization test indicates that the accuracy lost in weighting the soil type is greatest, therefore it needs to be weighted in a systematic manner to formulate equivalent cross-sections. If the soil type remains the same within the sub-basin, a single equivalent cross-section is formulated for the entire sub-basin. If the soil type follows a specific pattern, i.e. different soil types near the centre of the river, middle of hillslope and ridge line, three equivalent cross-sections (left bank, right bank and head water) are required. If the soil types are complex and do not follow any specific pattern, multiple equivalent cross-sections are required based on the number of soil types. The equivalent cross-sections are formulated for a series of first order sub-basins by implementing different weighting methods of topographic and physiographic variables of landforms within the entire or part of a hillslope. The formulated equivalent cross-sections are then simulated using a 2-dimensional, Richards' equation based distributed hydrological model. The simulated fluxes are multiplied by the weighted area of each equivalent cross-section to calculate the total fluxes from the sub-basins. The simulated fluxes include horizontal flow, transpiration, soil evaporation, deep drainage and soil moisture. To assess the accuracy of equivalent cross-section approach, the sub-basins are also divided into equally spaced multiple hillslope cross-sections. These cross-sections are simulated in a fully distributed settings using the 2-dimensional, Richards' equation based distributed hydrological model. The simulated fluxes are multiplied by the contributing area of each cross-section to get total fluxes from each sub-basin referred as reference fluxes. The equivalent cross-section approach is investigated for seven first order sub-basins of the McLaughlin catchment of the Snowy River, NSW, Australia, and evaluated in Wagga-Wagga experimental catchment. Our results show that the simulated fluxes using an equivalent cross-section approach are very close to the reference fluxes whereas computational time is reduced of the order of ~4 to ~22 times in comparison to the fully distributed settings. The transpiration and soil evaporation are the dominant fluxes and constitute ~85% of actual rainfall. Overall, the accuracy achieved in dominant fluxes is higher than the other fluxes. The simulated soil moistures from equivalent cross-section approach are compared with the in-situ soil moisture observations in the Wagga-Wagga experimental catchment in NSW, and results found to be consistent. Our results illustrate that the equivalent cross-section approach reduces the computational time significantly while maintaining the same order of accuracy in predicting the hydrological fluxes. As a result, this approach provides a great potential for implementation of distributed hydrological models at regional scales.
A web-based Tamsui River flood early-warning system with correction of real-time water stage using monitoring data

NASA Astrophysics Data System (ADS)

Liao, H. Y.; Lin, Y. J.; Chang, H. K.; Shang, R. K.; Kuo, H. C.; Lai, J. S.; Tan, Y. C.

2017-12-01

Taiwan encounters heavy rainfalls frequently. There are three to four typhoons striking Taiwan every year. To provide lead time for reducing flood damage, this study attempt to build a flood early-warning system (FEWS) in Tanshui River using time series correction techniques. The predicted rainfall is used as the input for the rainfall-runoff model. Then, the discharges calculated by the rainfall-runoff model is converted to the 1-D river routing model. The 1-D river routing model will output the simulating water stages in 487 cross sections for the future 48-hr. The downstream water stage at the estuary in 1-D river routing model is provided by storm surge simulation. Next, the water stages of 487 cross sections are corrected by time series model such as autoregressive (AR) model using real-time water stage measurements to improve the predicted accuracy. The results of simulated water stages are displayed on a web-based platform. In addition, the models can be performed remotely by any users with web browsers through a user interface. The on-line video surveillance images, real-time monitoring water stages, and rainfalls can also be shown on this platform. If the simulated water stage exceeds the embankments of Tanshui River, the alerting lights of FEWS will be flashing on the screen. This platform runs periodically and automatically to generate the simulation graphic data of flood water stages for flood disaster prevention and decision making.
Sand deposition in the Colorado River in the Grand Canyon from flooding of the Little Colorado River

USGS Publications Warehouse

Wiele, S.M.; Graf, J.B.; Smith, J.D.

1996-01-01

Methods for computing the volume of sand deposited in the Colorado River in Grand Canyon National Park by floods in major tributaries and for determining redistribution of that sand by main-channel flows are required for successful management of sand-dependent riparian resources. We have derived flow, sediment transport, and bed evolution models based on a gridded topography developed from measured channel topography and used these models to compute deposition in a short reach of the river just downstream from the Little Colorado River, the largest tributary in the park. Model computations of deposition from a Little Colorado River flood in January 1993 were compared to bed changes measured at 15 cross sections. The total difference between changes in cross-sectional area due to deposition computed by the model and the measured changes was 6%. A wide reach with large areas of recirculating flow and large depressions in the main channel accumulated the most sand, whereas a reach with similar planimetric area but a long, narrow shape and relatively small areas of recirculating flow and small depressions in the main channel accumulated only about a seventh as much sand. About 32% of the total deposition was in recirculation zones, 65% was in the main channel, and 3% was deposited along the channel margin away from the recirculation zone. Overall, about 15% of the total input of sand from this Little Colorado River flood was deposited in the first 3 km below the confluence, suggesting that deposition of the flood-derived material extended for only several tens of kilometers downstream from the confluence.
Assessment of Flood Mitigation Solutions Using a Hydrological Model and Refined 2D Hydrodynamic Simulations

NASA Astrophysics Data System (ADS)

Khuat Duy, B.; Archambeau, P.; Dewals, B. J.; Erpicum, S.; Pirotton, M.

2009-04-01

Following recurrent inundation problems on the Berwinne catchment, in Belgium, a combined hydrologic and hydrodynamic study has been carried out in order to find adequate solutions for the floods mitigation. Thanks to detailed 2D simulations, the effectiveness of the solutions can be assessed not only in terms of discharge and height reductions in the river, but also with other aspects such as the inundated surfaces reduction and the decrease of inundated buildings and roads. The study is carried out in successive phases. First, the hydrological runoffs are generated using a physically based and spatially distributed multi-layer model solving depth-integrated equations for overland flow, subsurface flow and baseflow. Real floods events are simulated using rainfall series collected at 8 stations (over 20 years of available data). The hydrological inputs are routed through the river network (and through the sewage network if relevant) with the 1D component of the modelling system, which solves the Saint-Venant equations for both free-surface and pressurized flows in a unified way. On the main part of the river, the measured river cross-sections are included in the modelling, and existing structures along the river (such as bridges, sluices or pipes) are modelled explicitely with specific cross sections. Two gauging stations with over 15 years of continuous measurements allow the calibration of both the hydrologic and hydrodynamic models. Second, the flood mitigation solutions are tested in the simulations in the case of an extreme flooding event, and their effects are assessed using detailed 2D simulations on a few selected sensitive areas. The digital elevation model comes from an airborne laser survey with a spatial resolution of 1 point per square metre and is completed in the river bed with a bathymetry interpolated from cross-section data. The upstream discharge is extracted from the 1D simulation for the selected rainfall event. The study carried out with this methodology allowed to assess the suggested solutions with multiple effectiveness criteria and therefore constitutes a very useful support for decision makers.
AutoRoute Rapid Flood Inundation Model

DTIC Science & Technology

2013-03-01

Res. 33(2): 309-319. U.S. Army Engineer Hydrologic Engineering Center. 2010. “ HEC - RAS : River Analysis System, User’s Manual, Version 4.1.” Davis...cross-section data does not exist. As such, the AutoRoute model is not meant to be as accurate as models such as HEC - RAS (U.S. Army Engineer...such as HEC - RAS assume that the defined low point of cross sections must be connected. However, in this approach the channel is assumed to be defined
Validation of annual growth rings in freshwater mussel shells using cross dating .Can

Treesearch

Andrew L. Rypel; Wendell R. Haag; Robert H. Findlay

2009-01-01

We examined the usefulness of dendrochronological cross-dating methods for studying long-term, interannual growth patterns in freshwater mussels, including validation of annual shell ring formation. Using 13 species from three rivers, we measured increment widths between putative annual rings on shell thin sections and then removed age-related variation by...

Characteristics of the Cross-Sectional Vorticity of the Natural Spawning Grounds of Schizothorax prenanti and a Vague-Set Similarity Model for Ecological Restoration

PubMed Central

Liu, Ming-Yang; Zhang, Ling-Lei; Li, Jia; Li, Yong; Li, Nan; Chen, Ming-Qian

2015-01-01

Schizothorax prenanti is an endemic fish in the mountain rivers of southwestern China with unique protection value. To further explore the vortex motion of hydraulic habitats, which is closely related to the fish breeding process, the cross-sectional vorticity was used to evaluate the hydraulic conditions of the natural spawning habitat of S. prenanti. A coupled level-set and volume-of-fluid (CLSVOF) three-dimensional (3D) model was applied to simulate the hydraulic habitat of the Weimen reach, a typical natural spawning ground for S. prenanti in the upper Yangtze River. The model was used in conjunction with the Wilcoxon rank sum test to distinguish the distributions of vertical vorticity in spawning and non-spawning reaches. Statistical analysis revealed that the cross-sectional vorticity in spawning reaches was significantly greater than in non-spawning reaches, with likely biological significance in the spawning process. The range of cross-sectional mean values of vorticity was 0.17 s-1–0.35 s-1 in areas with concentrated fish sperm and eggs; the minimum value was 0.17 s-1, and the majority of values were greater than 0.26 s-1. Based on this study, a vague-set similarity model was used to assess the effectiveness of ecological restoration by evaluating the similarity of the cross-sectional vorticity of the natural spawning reach and rehabilitated spawning reach after implementing ecological restoration measures. The outcome might provide a theoretical basis for the recovery of damaged S. prenanti spawning grounds and act as an important complement for the assessment of recovery effectiveness and as a useful reference for the coordination of ecological water use with the demands of hydraulic and hydropower engineering. PMID:26317847
Specific absorption and backscatter coefficient signatures in southeastern Atlantic coastal waters

NASA Astrophysics Data System (ADS)

Bostater, Charles R., Jr.

1998-12-01

Measurements of natural water samples in the field and laboratory of hyperspectral signatures of total absorption and reflectance were obtained using long pathlength absorption systems (50 cm pathlength). Water was sampled in Indian River Lagoon, Banana River and Port Canaveral, Florida. Stations were also occupied in near coastal waters out to the edge of the Gulf Stream in the vicinity of Kennedy Space Center, Florida and estuarine waters along Port Royal Sound and along the Beaufort River tidal area in South Carolina. The measurements were utilized to calculate natural water specific absorption, total backscatter and specific backscatter optical signatures. The resulting optical cross section signatures suggest different models are needed for the different water types and that the common linear model may only appropriate for coastal and oceanic water types. Mean particle size estimates based on the optical cross section, suggest as expected, that particle size of oceanic particles are smaller than more turbid water types. The data discussed and presented are necessary for remote sensing applications of sensors as well as for development and inversion of remote sensing algorithms.
Mitigation of hazards from future lahars from Mount Merapi in the Krasak River channel near Yogyakarta, central Java

USGS Publications Warehouse

Ege, John R.; ,

1983-01-01

Procedures for reducing hazards from future lahars and debris flows in the Krasak River channel near Yogyakarta, Central Java, Indonesia, include (1) determining the history of the location, size, and effects of previous lahars and debris flows, and (2) decreasing flow velocities. The first may be accomplished by geologic field mapping along with acquiring information by interviewing local residents, and the second by increasing the cross sectional area of the river channel and constructing barriers in the flow path.
Magnetic fingerprint of the sediment load in a meander bend section of the Seine River (France)

NASA Astrophysics Data System (ADS)

Kayvantash, D.; Cojan, I.; Kissel, C.; Franke, C.

2017-06-01

This study aims to evaluate the potential of magnetic methods to determine the composition of the sediment load in a cross section of an unmanaged meander in the upstream stretch of the Seine River (Marnay-sur-Seine). Suspended particulate matter (SPM) was collected based on a regular sampling scheme along a cross section of the river, at two different depth levels: during a low-water stage (May 2014) and a high-water stage (February 2015). Riverbed sediments (RBS) were collected during the low-water stage and supplementary samples were taken from the outer and inner banks. Magnetic properties of the dry bulk SPM and sieved RBS and bank sediments were analysed. After characterizing the main magnetic carrier as magnetite, hysteresis parameters were measured, giving access to the grain size and the concentration of these magnetite particles. The results combined with sedimentary grain size data were compared to the three-dimensional velocity profile of the river flow. In the RBS where the magnetic grain size is rather uniform, the concentration of magnetite is inversely proportional to the mean grain size of the total sediment indicating that magnetite is strongly associated with the fine sedimentary fraction. The same pattern is observed in the samples from the outer and inner banks. During the low-water stage, the uniformly fine SPM grain size distribution characterizes the wash load. The magnetic fraction is also relatively fine (within the pseudo single domain range) with concentration similar to that of the fine RBS fraction. During the high-water stage, SPM samples correspond to mixtures of wash load and resuspended sediment from the bedload and riverbanks. Here, the grain size distribution is heterogeneous across the section showing coarser particles compared to those in the low-water stage and more varying magnetite concentrations while the magnetic grain size is like that of the low-water stage. The magnetite concentration in the high-water SPM can be modelled based on a mixing of the magnetite concentrations of the different grain size fractions, thus quantifying the impact of resuspension in the cross section.
Ecological condition of the East Fork of the Gila River and selected tributaries: Gila National Forest, New Mexico

Treesearch

Robert D. Ohmart

1996-01-01

Ecological condition of riparian habitats along the East Fork of the Gila River, Main Diamond Creek, lower South Diamond Creek, and Black Canyon Creek are all in very heavily degraded condition. Channel cross-sections show extensive entrenchment, high width-to-depth ratios, and numerous reaches where banks are sloughing into the stream, especially on the East Fork of...
A numerical model for the solution of the Shallow Water equations in composite channels with movable bed

NASA Astrophysics Data System (ADS)

minatti, L.

2013-12-01

A finite volume model solving the shallow water equations coupled with the sediments continuity equation in composite channels with irregular geometry is presented. The model is essentially 1D but can handle composite cross-sections in which bedload transport is considered to occur inside the main channel only. This assumption is coherent with the observed behavior of rivers on short time scales where main channel areas exhibit more relevant morphological variations than overbanks. Furthermore, such a model allows a more precise prediction of thalweg elevation and cross section shape variations than fully 1D models where bedload transport is considered to occur uniformly over the entire cross section. The coupling of the equations describing water and sediments dynamics results in a hyperbolic non-conservative system that cannot be solved numerically with the use of a conservative scheme. Therefore, a path-conservative scheme, based on the approach proposed by Pares and Castro (2004) has been devised in order to account for the coupling with the sediments continuity equation and for the concurrent presence of bottom elevation and breadth variations of the cross section. In order to correctly compute numerical fluxes related to bedload transport in main channel areas, a special treatment of the equations is employed in the model. The resulting scheme is well balanced and fully coupled and can accurately model abrupt time variations of flow and bedload transport conditions in wide rivers, characterized by the presence of overbank areas that are less active than the main channel. The accuracy of the model has been first tested in fixed bed conditions by solving problems with a known analytical solution: in these tests the model proved to be able to handle shocks and supercritical flow conditions properly(see Fig. 01). A practical application of the model to the Ombrone river, southern Tuscany (Italy) is shown. The river has shown relevant morphological changes during the last fifteen years, most of them related to the occurrence of high flow rates. The employment of the model allowed to perform a detailed flood hazard assessment where potential risks associated to bedload transport,such as sediments filling of manufacts, excessive erosion or aggradation rates have been evaluated, together with the more 'classical' evaluation of water levels. The whole process also led to the identification of sensitive reaches of the river that require monitoring thus allowing better management practices of the public money allocated for river maintenance. Solution of the Riemann problem for a 10 m wide rectangular XS. The dotted lines represent the numerical solution, while the continuous ones represent the analytical solution
Channel Bank Cohesion and the Maintenance of Suspension Rivers

NASA Astrophysics Data System (ADS)

Dunne, K. B. J.; Jerolmack, D. J.

2017-12-01

Gravel-bedded rivers organize their channel geometry and grain size such that transport is close to the threshold of motion at bankfull. Sand-bedded rivers, however, typically maintain bankfull fluid shear (or Shields) stresses far in excess of threshold; there is no widely accepted explanation for these "suspension rivers". We propose that all alluvial rivers are at the threshold of motion for their erosion-limiting material, i.e., the structural component of the river cross-section that is most difficult to mobilize. The entrainment threshold of gravel is large enough that bank cohesion has little influence on gravel-bed rivers. Sand, however, is the most easily entrained material; silt and clay can raise the entrainment threshold of sand by orders of magnitude. We examine a global dataset of river channel geometry and show that the shear stress range for sand-bedded channels is entirely within the range of entrainment thresholds for sand-mud mixtures - suggesting that rivers that suspend their sandy bed material are still threshold rivers in terms of bank material. We then present new findings from a New Jersey coastal-plain river examining if and how river-bank toe composition controls hydraulic geometry. We consider the toe because it is the foundation of the river bank, and its erosion leads to channel widening. Along a 20-km profile of the river we measure cross-section geometry, bed slope, and bed and bank composition, and we explore multiple methods of measuring the threshold shear stress of the the river-bank toe in-situ. As the composition of the river bed transitions from gravel to sand, we see preliminary evidence of a shift from bed-threshold to bank-threshold control on hydraulic geometry. We also observe that sub-bankfull flows are insufficient to erode (cohesive) bank materials, even though transport of sand is active at nearly all flows. Our findings highlight the importance of focusing on river-bank toe material, which in the studied stream is always submerged. The toe is more compacted and more resistant to erosion than the subaerially-exposed upper bank. We find mounting evidence that sand-bedded rivers are much like gravel-bedded river; they are near-threshold channels in which the suspended load does not play a controlling role in the determination of equilibrium hydraulic geometry.
Multiple Deltas Built Out Over Time

NASA Image and Video Library

2014-12-08

This diagram depicts a vertical cross section through geological layers deposited by rivers, deltas and lakes. Deposits from a series of successive deltas build out increasingly high in elevation as they migrate toward the center of the basin.
Flood prediction, its risk and mitigation for the Babura River with GIS

NASA Astrophysics Data System (ADS)

Tarigan, A. P. M.; Hanie, M. Z.; Khair, H.; Iskandar, R.

2018-03-01

This paper describes the flood prediction along the Babura River, the catchment of which is within the comparatively larger watershed of the Deli River which crosses the centre part of Medan City. The flood plain and ensuing inundation area were simulated using HECRAS based on the available data of rainfall, catchment, and river cross-sections. The results were shown in a GIS format in which the city map of Medan and other infrastructure layers were stacked for spatial analysis. From the resulting GIS, it can be seen that 13 sub-districts were likely affected by the flood, and then the risk calculation of the flood damage could be estimated. In the spirit of flood mitigation thoughts, 6 locations of evacuation centres were identified and 15 evacuation routes were recommended to reach the centres. It is hoped that the flood prediction and its risk estimation in this study will inspire the preparedness of the stakeholders for the probable threat of flood disaster.
Development of Conceptual Designs for the Prevention of Ice Formation in the Proposed Maple River Aqueduct

DTIC Science & Technology

2014-09-18

USA 1907 Reinforced concrete 50 × 6 × up to 350 ft various heights 35 ft 1675 2244 7 creeks and the Green River/ Hennepin Canal Solid...2 1 1 2 2e xs f U Uh L S C g g α α = + − (4) where Lxs = the distance between cross sections, g = the acceleration of gravity, α1 and α2 = the
Photographic copy of original drawing, by Corps of Engineers, U.S. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photographic copy of original drawing, by Corps of Engineers, U.S. Army, February 1939 (original in possession of Corps of Engineers, U.S. Army, Pittsburgh District, Engineering Division files) Unit 2, cross sections, STA. 96+52.0 to STA. 101+53.5 - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA
A Computational Model to Simulate Groundwater Seepage Risk in Support of Geotechnical Investigations of Levee and Dam Projects

DTIC Science & Technology

2013-03-01

Allen 1974, 1978; Bridge and Leeder 1979; Mackey and Bridge 1992) that computes synthetic stratigraphy for a floodplain cross section. The model...typical of that used to record and communicate geologic information for engineering applications. The computed stratigraphy differentiates between...belt dimensions measured for two well-studied river systems: (A) the Linge River within the Rhine-Meuse Delta , Netherlands, and (B) the Lower
Channel-conveyance capacity, channel change, and sediment transport in the lower Puyallup, White, and Carbon Rivers, western Washington

USGS Publications Warehouse

Czuba, Jonathan A.; Czuba, Christiana R.; Magirl, Chistopher S.; Voss, Frank D.

2010-01-01

Draining the volcanic, glaciated terrain of Mount Rainier, Washington, the Puyallup, White, and Carbon Rivers convey copious volumes of water and sediment down to Commencement Bay in Puget Sound. Recent flooding in the lowland river system has renewed interest in understanding sediment transport and its effects on flow conveyance throughout the lower drainage basin. Bathymetric and topographic data for 156 cross sections were surveyed in the lower Puyallup River system by the U.S. Geological Survey (USGS) and were compared with similar datasets collected in 1984. Regions of significant aggradation were measured along the Puyallup and White Rivers. Between 1984 and 2009, aggradation totals as measured by changes in average channel elevation were as much as 7.5, 6.5, and 2 feet on the Puyallup, White, and Carbon Rivers, respectively. These aggrading river sections correlated with decreasing slopes in riverbeds where the rivers exit relatively confined sections in the upper drainage and enter the relatively unconstricted valleys of the low-gradient Puget Lowland. Measured grain-size distributions from each riverbed showed a progressive fining downstream. Analysis of stage-discharge relations at streamflow-gaging stations along rivers draining Mount Rainier demonstrated the dynamic nature of channel morphology on river courses influenced by glaciated, volcanic terrain. The greatest rates of aggradation since the 1980s were in the Nisqually River near National (5.0 inches per year) and the White River near Auburn (1.8 inches per year). Less pronounced aggradation was measured on the Puyallup River and the White River just downstream of Mud Mountain Dam. The largest measured rate of incision was measured in the Cowlitz River at Packwood (5.0 inches per year). Channel-conveyance capacity estimated using a one-dimensional hydraulic model decreased in some river reaches since 1984. The reach exhibiting the largest decrease (about 20-50 percent) in channel-conveyance capacity was the White River between R Street Bridge and the Lake Tapps return, a reach affected by recent flooding. Conveyance capacity also decreased in sections of the Puyallup River. Conveyance capacity was mostly unchanged along other study reaches. Bedload transport was simulated throughout the entire river network and consistent with other observations and analyses, the hydraulic model showed that the upper Puyallup and White Rivers tended to accumulate sediment. Accuracy of the bedload-transport modeling, however, was limited due to a scarcity of sediment-transport data sets from the Puyallup system, mantling of sand over cobbles in the lower Puyallup and White Rivers, and overall uncertainty in modeling sediment transport in gravel-bedded rivers. Consequently, the output results from the model were treated as more qualitative in value, useful in comparing geomorphic trends within different river reaches, but not accurate in producing precise predictions of mass of sediment moved or deposited. The hydraulic model and the bedload-transport component were useful for analyzing proposed river-management options, if surveyed cross sections adequately represented the river-management site and proposed management options. The hydraulic model showed that setback levees would provide greater flood protection than gravel-bar scalping after the initial project construction and for some time thereafter, although the model was not accurate enough to quantify the length of time of the flood protection. The greatest hydraulic benefit from setback levees would be a substantial increase in the effective channel-conveyance area. By widening the distance between levees, the new floodplain would accommodate larger increases in discharge with relatively small incremental increases in stage. Model simulation results indicate that the hydraulic benefit from a setback levee also would be long-lived and would effectively compensate for increased deposition within the setback reach
Velocity, bathymetry, and transverse mixing characteristics of the Ohio River upstream from Cincinnati, Ohio, October 2004-March 2006

USGS Publications Warehouse

Koltun, G.F.; Ostheimer, Chad J.; Griffin, Michael S.

2006-01-01

Velocity, bathymetry, and transverse (cross-channel) mixing characteristics were studied in a 34-mile study reach of the Ohio River extending from the lower pool of the Captain Anthony Meldahl Lock and Dam, near Willow Grove, Ky, to just downstream from the confluence of the Licking and Ohio Rivers, near Newport, Ky. Information gathered in this study ultimately will be used to parameterize hydrodynamic and water-quality models that are being developed for the study reach. Velocity data were measured at an average cross-section spacing of about 2,200 feet by means of boat-mounted acoustic Doppler current profilers (ADCPs). ADCP data were postprocessed to create text files describing the three-dimensional velocity characteristics in each transect. Bathymetry data were measured at an average transect spacing of about 800 feet by means of a boat-mounted single-beam echosounder. Depth information obtained from the echosounder were postprocessed with water-surface slope and elevation information collected during the surveys to compute stream-bed elevations. The bathymetry data were written to text files formatted as a series of space-delimited x-, y-, and z-coordinates. Two separate dye-tracer studies were done on different days in overlapping stream segments in an 18.3-mile section of the study reach to assess transverse mixing characteristics in the Ohio River. Rhodamine WT dye was injected into the river at a constant rate, and concentrations were measured in downstream cross sections, generally spaced 1 to 2 miles apart. The dye was injected near the Kentucky shoreline during the first study and near the Ohio shoreline during the second study. Dye concentrations were measured along transects in the river by means of calibrated fluorometers equipped with flow-through chambers, automatic temperature compensation, and internal data loggers. The use of flow-through chambers permitted water to be pumped continuously out of the river from selected depths and through the fluorometer for measurement as the boat traversed the river. Time-tagged concentration readings were joined with horizontal coordinate data simultaneously captured from a differentially corrected Global Positioning System (GPS) device to create a plain-text, comma-separated variable file containing spatially tagged dye-concentration data. Plots showing the transverse variation in relative dye concentration indicate that, within the stream segments sampled, complete transverse mixing of the dye did not occur. In addition, the highest concentrations of dye tended to be nearest the side of the river from which the dye was injected. Velocity, bathymetry, and dye-concentration data collected during this study are available for Internet download by means of hyperlinks in this report. Data contained in this report were collected between October 2004 and March 2006.
Computational Fluid Dynamics Modeling of the John Day Dam Tailrace

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C.

US Army Corps of Engineers - Portland District required that a two-dimensional (2D) depth-averaged and a three-dimensional (3D) free-surface numerical models to be developed and validated for the John Day tailrace. These models were used to assess potential impact of a select group of structural and operational alternatives to tailrace flows aimed at improving fish survival at John Day Dam. The 2D model was used for the initial assessment of the alternatives in conjunction with a reduced-scale physical model of the John Day Project. A finer resolution 3D model was used to more accurately model the details of flow inmore » the stilling basin and near-project tailrace hydraulics. Three-dimensional model results were used as input to the Pacific Northwest National Laboratory particle tracking software, and particle paths and times to pass a downstream cross section were used to assess the relative differences in travel times resulting from project operations and structural scenarios for multiple total river flows. Streamlines and neutrally-buoyant particles were seeded in all turbine and spill bays with flows. For a Total River of 250 kcfs running with the Fish Passage Plan spill pattern and a spillwall, the mean residence times for all particles were little changed; however the tails of the distribution were truncated for both spillway and powerhouse release points, and, for the powerhouse releases, reduced the residence time for 75% of the particles to pass a downstream cross section from 45.5 minutes to 41.3 minutes. For a total river of 125 kcfs configured with the operations from the Fish Passage Plan for the temporary spillway weirs and for a proposed spillwall, the neutrally-buoyant particle tracking data showed that the river with a spillwall in place had the overall mean residence time increase; however, the residence time for 75% of the powerhouse-released particles to pass a downstream cross section was reduced from 102.4 min to 89 minutes.« less
Annual bed-elevation regime in the alluvial channel of Squamish River, southwestern British Columbia Canada

USGS Publications Warehouse

Stanford, S.D.; Seidl, M.A.; Ashley, G.M.

2000-01-01

The aim of this study is to examine the annual regime of channel scour and fill by monitoring bed-elevation changes in a reach of Squamish River in southwestern British Columbia, Canada. Sonar surveys of 13 river cross-sections in a sandy gravel-bed single-channel study reach were repeated biweekly over a full hydrologic year (1995/6). The survey results show that bedload movement occurs as waves or pulses forming bedwaves that appear to maintain an overall coherence with movement downstream. These bedwaves propagate downstream by a mode here termed pulse scour and pulse fill, a process distinguished from the conventional mode of scour and fill commonly associated with flood events (here termed local scour and local fill). Bedwave celerity was estimated to be about 15.5 m d-1 corresponding to a bedwave residence time in the study reach of almost one hydrologic year. The total amount of local bed-elevation change ranged between 0.22 m and 2.41 m during the period of study. Analysis of the bed-elevation and flow data reveals that, because of the bedware phenomenon, there is no simple relation between the mean bed-elevation and discharge nor any strong linear correlation among cross-sectional behaviour. The bed-elevation data also suggest that complex changes to the bed within a cross-section are masked when the bed is viewed in one dimension, although no definitive trends in bed behaviour were found in the two-dimensional analysis. Although a weak seasonal effect is evident in this study, the bed-elevation regime is dominated by sediment supply-driven fluctuations in bedload transport occurring at timescales shorter than the seasonal fluctuation in discharge. The study also indicates that bed-elevation monitoring on Squamish River, and others like it, for purposes of detecting and measuring aggradation/degradation must take into account very considerable and normal channel-bed variability operating at timescales from hours to months. Copyright (C) 2000 John Wiley and Sons, Ltd.
Cross-channel variability in benthic habitat

USGS Publications Warehouse

Vayssieres, Marc; Peterson, Heather

2003-01-01

The Interagency Ecological Program’s Environmental Monitoring Program (EMP) has monitored benthic invertebrates since the mid-1970s. A recent review of the EMP found that the spatial study design of the benthos monitoring element was in need of a thorough reexamination through intense special studies and extensive historic data analyses. This article reports the results of preliminary analyses of historical EMP data focusing on cross-channel variability. Specific questions are: (1) do benthic habitats and community assemblages vary between positions across a river channel? (2) Are benthic samples taken at a single channel position sufficiently representative of benthos assemblages across the channel to characterize long term changes in the benthos community of a particular section of a river?
Hydropower production from bridges in urban or suburban areas

NASA Astrophysics Data System (ADS)

Tucciarelli, Tullio; Sammartano, Vincenzo; Sinagra, Marco; Morreale, Gabriele; Ferreira, Teresa

2015-04-01

A new technology for hydropower production from rivers crossing urban or suburban areas is proposed, based on the use of Cross-Flow turbines having its axis horizontal and normal to the flow direction. A large part of the river cross-section could be covered by the turbine cross-section and this would generate a small, but consistent jump between the water levels of the inlet and the outlet sections. The turbine should be anchored to a pre-existing bridge and the total length of its axis should be of the same order of the bridge length. Due to the large axis extension, it should be possible to easily attain a gross power similar to the power produced with a more traditional installation, based on weirs or barrages, if single jumps of few tens of centimeters were added over a large number of bridges. If the bridges were set in urbanized areas, the production of electricity would be located close to its consumption, according to the smart grid requirements, and the hydrological basin at the bridge section (along with the corresponding discharge) would be greater than the basin of traditional plants located in more upstream locations. The maximum water level to be attained in the upstream section of the bridge should be the minimum among the following ones: 1) the level corresponding to the maximum flood allowed by the surrounding infra-structures, 2) the level corresponding to the maximum force allowed by the bridge structures. The resulting upstream water level hydrographs should be compatible with the river suspended and bed load equilibrium and with the requirement of the aquatic living population. The system should include a mechanism able to raise the turbine completely out of the water level, if required, for maintenance or other purposes. The complete lifting of the turbine could be used to: a) reconstruct the natural river bed profile during floods, b) allow the navigation or fish movements during some periods of the year, or even some hours of the day. A possible technology which would allow the accomplishment of the proposed targets is the use of a Cross-Flow turbine, arranged according to the scheme of Fig.1, where: - the position of the rotating wall (rw) is set according to the pressure measured at its top, so that a small but constant falling discharge (Q2) is guaranteed. This falling discharge allows the transition of floating objects and hid the all machinery, with an obvious skyline improvement. - the average distance d is set in order to guarantee in the confined channel below the turbine an average velocity V similar to the original one existing in the river. PIC Fig.1 - Scheme of the river Cross-Flow turbine. Observe in Fig.2 the results of a CFX simulation, carried on with the following input data for a large rectangular section per unit width: ho (m) h1(m) h2 (m) d(m) 1.5314 1.99 0.082 0.1021 Q2(m2/s) Q3(m2/s)w (r.p.m.)V0(m/s) 0.04 0.267 27 2.61 Table 1. Input data for the CFD simulation. Simulation have been carried out using ANSYS code, with a computational domain divided using both tetrahedral and prismatic elements. The mechanical power estimated at the rotational shaft was of 4.84 KW/m and the hydraulic power of the water stream was of 7.25 KW/m. Thus the turbine efficiency was of about 49.97 %. PIC Fig.2 - Vectors velocity water field close to the Cross-Flow turbine domain. From the environmental point of view the turbine constitutes nonetheless a physical barrier that moving organisms will have to negotiate on their movements through the blades, particularly larger ones such as fish. Also, the hydraulic environment of the river will be modified, e.g. turbulence, shear stress, pressure and flow patterns, affecting as well the smaller organisms. While developing the turbine, a thorough appraisal of its environmental consequences for aquatic ecosystems has to be done, in order to develop an environmentally-friendly structure, embedding mitigation aspects. Furthermore, the structure itself will be subject to colonization on its surfaces by a biological matrix including microbial organisms but also filamentous algae and aquatic macrophytes, either anchored of clogging to the structure while drifting downstream. When developing the turbine, the side-effects of such epibiosis have to be evaluated, given the evidence already existing in rivers and canals, of harmful vegetation interfering with irrigation and transport structures.
Sources and routing of the Amazon River Flood Wave

NASA Astrophysics Data System (ADS)

Richey, Jeffrey E.; Mertes, Leal A. K.; Dunne, Thomas; Victoria, Reynaldo L.; Forsberg, Bruce R.; Tancredi, AntôNio C. N. S.; Oliveira, Eurides

1989-09-01

We describe the sources and routing of the Amazon River flood wave through a 2000-km reach of the main channel, between São Paulo de Olivença and Obidos, Brazil. The damped hydrograph of the main stem reflects the large drainage basin area, the 3-month phase lag in peak flows between the north and south draining tributaries due to seasonal differences in precipitation, and the large volume of water stored on the floodplain. We examined several aspects of the valley floor hydrology that are important for biogeochemistry. These include volumes of water storage in the channel and the floodplain and the rates of transfer between these two storage elements at various seasons and in each segment of the valley. We estimate that up to 30% of the water in the main stem is derived from water that has passed through the floodplain. To predict the discharge at any cross section within the study reach, we used the Muskingum formula to predict the hydrograph at downriver cross sections from a known hydrograph at upstream cross-sections and inputs and outputs along each reach. The model was calibrated using three years of data and was successfully tested against an additional six years of data. With this model it is possible to interpolate discharges for unsampled times and sites.
Backwater at bridges and densely wooded flood plains, west fork Amite River near Liberty, Mississippi

USGS Publications Warehouse

Colson, B.E.; Ming, C.O.; Arcement, George J.

1979-01-01

Floodflow data that will provide a base for evaluating digital models relating to open-channel flow were obtained at 22 sites on streams in Alabama, Louisiana, and Mississippi. Thirty-five floods were measured. Analysis of the data indicated methods currently in use would be inaccurate where densely vegetated flood plains are crossed by highway embankments and single-opening bridges. This atlas presents flood information at the site on West Fork Amite River near Liberty, MS. Water depths , velocities, and discharges through bridge openings on West Fork Amite River near Liberty, MS for floods of December 6, 1971 , and March 25, 1973, are shown, together with peak water-surface elevations along embankments and along cross sections. Manning 's roughness coefficient values in different parts of the flood plain are shown on maps, and flood-frequency relations are shown on a graph. (USGS).

Stream channel cross sections for a reach of the Boise River in Ada County, Idaho

USGS Publications Warehouse

Hortness, Jon E.; Werner, Douglas C.

1999-01-01

The Federal Emergency Management Agency produces maps of areas that are likely to be inundated during major floods, usually the 100-year, or 1-percent probability, flood. The maps, called Flood Insurance Rate Maps, are used to determine flood insurance rates for homes, businesses, or other structures located in flood-prone areas. State and local governments also use these maps for help with, among other things, development planning and disaster mitigation. During the period October 1997 through December 1998, the initial phase of a hydraulic analysis project of the Boise River from Barber Dam to the Ada/Canyon County boundary, the U.S. Geological Survey collected stream channel cross-section data at 238 locations along the river and documented 108 elevation reference marks established for horizontal and vertical control. In the final phase of the project, the Survey will use these data to determine water-surface elevations for the 10-, 50-, 100-, and 500-year floods and to define floodway limits. The Federal Emergency Management Agency will use the results of this hydraulic analysis to update the 100- and 500-year flood boundaries and the floodway limits on their Flood Insurance Rate Maps.
9. Photocopy of Blueprint (Original held by the Community end ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. Photocopy of Blueprint (Original held by the Community end Economic Development Department, City of Detroit), C. Howard Crane, Architect. CROSS SECTION THROUGH STADIUM, NOVEMBER 27, 1926. (4' x 5' negative) - Olympia Arena, 5920 Grand River Avenue, Detroit, MI
Simulation of multistatic and backscattering cross sections for airborne radar

NASA Astrophysics Data System (ADS)

Biggs, Albert W.

1986-07-01

In order to determine susceptibilities of airborne radar to electronic countermeasures and electronic counter-countermeasures simulations of multistatic and backscattering cross sections were developed as digital modules in the form of algorithms. Cross section algorithms are described for prolate (cigar shape) and oblate (disk shape) spheroids. Backscattering cross section algorithms are also described for different categories of terrain. Backscattering cross section computer programs were written for terrain categorized as vegetation, sea ice, glacial ice, geological (rocks, sand, hills, etc.), oceans, man-made structures, and water bodies. PROGRAM SIGTERRA is a file for backscattering cross section modules of terrain (TERRA) such as vegetation (AGCROP), oceans (OCEAN), Arctic sea ice (SEAICE), glacial snow (GLASNO), geological structures (GEOL), man-made structures (MAMMAD), or water bodies (WATER). AGCROP describes agricultural crops, trees or forests, prairies or grassland, and shrubs or bush cover. OCEAN has the SLAR or SAR looking downwind, upwind, and crosswind at the ocean surface. SEAICE looks at winter ice and old or polar ice. GLASNO is divided into a glacial ice and snow or snowfields. MANMAD includes buildings, houses, roads, railroad tracks, airfields and hangars, telephone and power lines, barges, trucks, trains, and automobiles. WATER has lakes, rivers, canals, and swamps. PROGRAM SIGAIR is a similar file for airborne targets such as prolate and oblate spheroids.
Laminar laboratory rivers

NASA Astrophysics Data System (ADS)

Seizilles, Grégoire; Devauchelle, Olivier; Lajeunesse, Éric; Métivier, François

2014-05-01

A viscous fluid flowing over fine plastic grains spontaneously channelizes into a few centimeters-wide river. After reaching its equilibrium shape, this stable laboratory flume is able to carry a steady load of sediments, like many alluvial rivers. When the sediment discharge vanishes, the river size, shape and slope fit the threshold theory proposed by Glover and Florey (1951), which assumes that the Shields parameter is critical on the channel bed. As the sediment discharge is increased, the river widens and flattens. Surprisingly, the aspect ratio of its cross section depends on the sediment discharge only, regardless of the water discharge. We propose a theoretical interpretation of these findings based on the balance between gravity, which pulls particles towards the center of the channel, and the diffusion of bedload particles, which pushes them away from areas of intense bedload.
Directional Gila River crossing saves construction, mitigation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saylor, L.A.

1994-12-01

Directional drilled river crossing technology gained a new convert this fall as El Paso Natural Gas Co. (EPNG) replaced a washed out 10 3/4-in. line that crossed the Gila River and two irrigation canals near Yuma, Ariz. The 1,650-ft bore, the company's first drilled river crossing, saved both construction costs and environmental reporting and mitigation expenses. This paper reviews the planning, engineering, and equipment used to install this river pipeline crossing.
River habitat assessment for ecological restoration of Wei River Basin, China.

PubMed

Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia

2018-04-11

As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.
Changes in sinuosities of the rivers at geological structural lines in the Pannonian Basin - Mosaics to the neotectonic image of the region

NASA Astrophysics Data System (ADS)

Petrovszki, Judit

2010-05-01

In the central, flat area of the Pannonian Basin, there are just few topographic features for neotectonic investigations. However, a lot of meandering rivers flow here, and it is possible to reconstruct their natural, pre-regulation planforms. Using the map sheets of the Second Military Survey of the Habsburg Empire (mid-19th century; Timár et al., 2006), I digitized the meandering rivers on this area. Sinuosities at different sample section lengths were computed in a GIS environment, providing so-called 'sinuosity-spectra' (van Balen et al., 2008) for each point of the analyzed channels. The channel sinuosity of this river systems are analyzed in order to draw conclusions on the neotectonic activity of the Great Hungarian Plain and the other flat areas of the Pannonian Basin. Several points of sinuosity change were identified. To prove, that these are of neotectonic origin, seismic sections crossing the study area, were also analyzed as well as the geodinamical map of the area (Horváth et al., 2006). High sinuosity variations (low to high or high to low), spatially correlated to linear features identified in seismic survey sections, indicating their neotectonic activity (after Ouchi, 1985). We can see two significante sinuosity changes on the Hron/Garam River (Slovakia), one at Tekov and the one at Kéménd. There are faults on the neotectonic map at these points, crossing the river - they are the possible causes of the increasing of the sinuosity. The vertical activity of these structural lines is verified by the sinuosity changes. At the Maros/Mureş River (Romania/Hungary), a significant sinuosity change can also be identified near to the town of Aiud, where the phenomene is just the opposite like in the Hron/Garam river. There is a fault on the neotectonic map crossing the river. Upstream of the river has higher sinuosity values, and after crossing the fault, it decresed. Here also the fault caused the sinuosity changing, so this fault is also an active one. However, there are more case studies, concerning the rivers of the Pannonian Basin, such as the Tisza River (Timár, 2003), the Körös system (Petrovszki and Timár, 2010), the creeks of the Little Hungarian Plain (Zámolyi et al., 2010) and the downstream part of the Danube (Petrovszki, 2010), providing a broader overview of the river-confirmed neotectonic activity of the region. Horváth, F., Bada, G., Windhoffer, G., Csontos, L., Dombrádi, E., Dövényi, P., Fodor, L., Grenerczy, Gy., Síkhegyi, F., Szafián, P., Székely, B., Timár, G., Tóth, L., Tóth, T. (2006): A Pannon-medence jelenkori geodinamikájának atlasza: Euro-konform térképsorozat és magyarázó. Magyar Geofizika 47(4), 133-137. Ouchi, S. (1985): Response of alluvial rivers to slow active tectonic movement. Geol. Soc. Am. Bull. 96, 504-515. Petrovszki, J. (2010): Sinuosity calculations of the Danube River between Paks (Hungary) and Beograd (Serbia). Geophysical Research Abstracts. Vol. 12, EGU2010-4571 Petrovszki, J., Timár, G. (2010): Channel sinuosity of the Körös River system, Hungary/Romania, as possible indicator of the neotectonic activity. Geomorphology, in press, DOI: 10.1016/j.geomorph.2009.11.009. Timár, G. (2003): Controls on channel sinuosity changes: a case study of the Tisza River, the Great Hungarian Plain. Quaternary Sci. Rev. 22, 2199-2207. Timár, G., Molnár, G., Székely, B., Biszak, S., Varga, J., Jankó, A. (2006): Digitized maps of the Habsburg Empire - The map sheets of the second military survey and their georeferenced version. Arcanum, Budapest, 59 p. van Balen, R. T., Kasse, C., Moor, J. (2008): Impact of groundwater flow on meandering; example from the Geul river, the Netherlands. Earth Surf. Process. and Landf. 33(13), 2010-2028. Zámolyi, A., Székely, B., Draganits, E., Timár, G. (2010): Neotectonic control on river sinuosity at the western margin of the Little Hungarian Plain. Geomorph., in press, DOI: 10.1016/j.geomorph.2009.06.028
Evaluating the potential for remote bathymetric mapping of a turbid, sand-bed river: 2. Application to hyperspectral image data from the Platte River

USGS Publications Warehouse

Legleiter, C.J.; Kinzel, P.J.; Overstreet, B.T.

2011-01-01

This study examined the possibility of mapping depth from optical image data in turbid, sediment-laden channels. Analysis of hyperspectral images from the Platte River indicated that depth retrieval in these environments is feasible, but might not be highly accurate. Four methods of calibrating image-derived depth estimates were evaluated. The first involved extracting image spectra at survey point locations throughout the reach. These paired observations of depth and reflectance were subjected to optimal band ratio analysis (OBRA) to relate (R2 = 0.596) a spectrally based quantity to flow depth. Two other methods were based on OBRA of data from individual cross sections. A fourth strategy used ground-based reflectance measurements to derive an OBRA relation (R2 = 0.944) that was then applied to the image. Depth retrieval accuracy was assessed by visually inspecting cross sections and calculating various error metrics. Calibration via field spectroscopy resulted in a shallow bias but provided relative accuracies similar to image-based methods. Reach-aggregated OBRA was marginally superior to calibrations based on individual cross sections, and depth retrieval accuracy varied considerably along each reach. Errors were lower and observed versus predicted regression R2 values higher for a relatively simple, deeper site than a shallower, braided reach; errors were 1/3 and 1/2 the mean depth for the two reaches. Bathymetric maps were coherent and hydraulically reasonable, however, and might be more reliable than implied by numerical metrics. As an example application, linear discriminant analysis was used to produce a series of depth threshold maps for characterizing shallow-water habitat for roosting cranes. ?? 2011 by the American Geophysical Union.
Evaluating the potential for remote bathymetric mapping of a turbid, sand-bed river: 2. application to hyperspectral image data from the Platte River

USGS Publications Warehouse

Legleiter, Carl J.; Kinzel, Paul J.; Overstreet, Brandon T.

2011-01-01

This study examined the possibility of mapping depth from optical image data in turbid, sediment-laden channels. Analysis of hyperspectral images from the Platte River indicated that depth retrieval in these environments is feasible, but might not be highly accurate. Four methods of calibrating image-derived depth estimates were evaluated. The first involved extracting image spectra at survey point locations throughout the reach. These paired observations of depth and reflectance were subjected to optimal band ratio analysis (OBRA) to relate (R2 = 0.596) a spectrally based quantity to flow depth. Two other methods were based on OBRA of data from individual cross sections. A fourth strategy used ground-based reflectance measurements to derive an OBRA relation (R2 = 0.944) that was then applied to the image. Depth retrieval accuracy was assessed by visually inspecting cross sections and calculating various error metrics. Calibration via field spectroscopy resulted in a shallow bias but provided relative accuracies similar to image-based methods. Reach-aggregated OBRA was marginally superior to calibrations based on individual cross sections, and depth retrieval accuracy varied considerably along each reach. Errors were lower and observed versus predicted regression R2 values higher for a relatively simple, deeper site than a shallower, braided reach; errors were 1/3 and 1/2 the mean depth for the two reaches. Bathymetric maps were coherent and hydraulically reasonable, however, and might be more reliable than implied by numerical metrics. As an example application, linear discriminant analysis was used to produce a series of depth threshold maps for characterizing shallow-water habitat for roosting cranes.
Modelling of Sediment Transport of the Mehadica River, Caras Severin County, Romania

NASA Astrophysics Data System (ADS)

Grozav, Adia; Beilicci, Robert; Beilicci, Erika

2017-10-01

Study case is situated in Caras-Severin County. Every sediment transport model application is different both in terms of time and space scale, study objectives, required accuracy, allocated resources, background of the study team etc. For sediment transport modelling, it is necessary to know the characteristics of the sediment in the river bed. Therefore, it is recommended to collect a number of bed sediment grap samples. These samples should be analysing in terms of grain size distribution. To solve theoretical problems of movement of water in the river Mehadica, it requires modelling of water flow in this case. Numerical modelling was performed using the program MIKE11. MIKE 11 is a user-friendly, fully dynamic, one-dimensional modelling tool for the detailed analysis, design, management and operation of both simple and complex river and channel systems. With its exceptional flexibility, speed and user friendly environment, MIKE 11 provides a complete and effective design environment for engineering, water resources, water quality management and planning applications. The Hydrodynamic (HD) module is the nucleus of the MIKE 11 modelling system and forms the basis for most modules including Flood Forecasting, Advection- Dispersion, Water Quality and Non-cohesive sediment transport modules. The MIKE 11 HD module solves the vertically integrated equations for the conservation of mass and momentum, i.e. the Saint-Venant equations. The input data are: area plan with location of cross sections; cross sections topographical data and roughness of river bed; flood discharge hydrograph. Advanced computational modules are included for description of flow over hydraulic structures, including possibilities to describe structure operation.
Qualitative simulation of bathymetric changes due to reservoir sedimentation: A Japanese case study.

PubMed

Bilal, Ahmed; Dai, Wenhong; Larson, Magnus; Beebo, Qaid Naamo; Xie, Qiancheng

2017-01-01

Sediment-dynamics modeling is a useful tool for estimating a dam's lifespan and its cost-benefit analysis. Collecting real data for sediment-dynamics analysis from conventional field survey methods is both tedious and expensive. Therefore, for most rivers, the historical record of data is either missing or not very detailed. Available data and existing tools have much potential and may be used for qualitative prediction of future bathymetric change trend. This study shows that proxy approaches may be used to increase the spatiotemporal resolution of flow data, and hypothesize the river cross-sections and sediment data. Sediment-dynamics analysis of the reach of the Tenryu River upstream of Sakuma Dam in Japan was performed to predict its future bathymetric changes using a 1D numerical model (HEC-RAS). In this case study, only annually-averaged flow data and the river's longitudinal bed profile at 5-year intervals were available. Therefore, the other required data, including river cross-section and geometry and sediment inflow grain sizes, had to be hypothesized or assimilated indirectly. The model yielded a good qualitative agreement, with an R2 (coefficient of determination) of 0.8 for the observed and simulated bed profiles. A predictive simulation demonstrated that the useful life of the dam would end after the year 2035 (±5 years), which is in conformity with initial detailed estimates. The study indicates that a sediment-dynamic analysis can be performed even with a limited amount of data. However, such studies may only assess the qualitative trends of sediment dynamics.
Qualitative and numerical analyses of the effects of river inflow variations on mixing diagrams in estuaries

USGS Publications Warehouse

Cifuentes, L.A.; Schemel, L.E.; Sharp, J.H.

1990-01-01

The effects of river inflow variations on alkalinity/salinity distributions in San Francisco Bay and nitrate/salinity distributions in Delaware Bay are described. One-dimensional, advective-dispersion equations for salinity and the dissolved constituents are solved numerically and are used to simulate mixing in the estuaries. These simulations account for time-varying river inflow, variations in estuarine cross-sectional area, and longitudinally varying dispersion coefficients. The model simulates field observations better than models that use constant hydrodynamic coefficients and uniform estuarine geometry. Furthermore, field observations and model simulations are consistent with theoretical 'predictions' that the curvature of propery-salinity distributions depends on the relation between the estuarine residence time and the period of river concentration variation. ?? 1990.
Floating Debris Control: A Literature Review

DTIC Science & Technology

1987-06-01

8, which are photographs of the Appalachian Power Company facility at the Winfield Lock and Dam on the Kanawha River. The cross section of the boom...gravity = 32.2 w weight of 1 cu ft of water, lb 62.5 T total tension in the boom, lb 18 Then, Figure 7. Debris diversion boom and debris... Appalachian Power Company Station at Winfield Lock and Dam, Kanawha River, West Virginia. 2 T = wRdv (sin a) = 1.94 Rdv2 (sin a) g (2) Ample allowances
Development of a spatially distributed model of fish population density for habitat assessment of rivers

NASA Astrophysics Data System (ADS)

Sui, Pengzhe; Iwasaki, Akito; Ryo, Masahiro; Saavedra, Oliver; Yoshimura, Chihiro

2013-04-01

Flow conditions play an important role in sustaining biodiversity of river ecosystem. However, their relations to freshwater fishes, especially to fish population density, have not been clearly described. This study, therefore, aimed to propose a new methodology to quantitatively link habitat conditions, including flow conditions and other physical conditions, to population density of fish species. We developed a basin-scale fish distribution model by integrating the concept of habitat suitability assessment with a distributed hydrological model (DHM) in order to estimate fish population density with particular attention to flow conditions. Generalized linear model (GLM) was employed to evaluate the relationship between population density of fish species and major environmental factors. The target basin was Sagami River in central Japan, where the river reach was divided into 10 sections by estuary, confluences of tributaries, and river-crossing structures (dams, weirs). The DHM was employed to simulate river discharge from 1998 to 2005, which was used to calculate 10 flow indices including mean discharge, 25th and 75th percentile discharge, duration of low and high flows, number of floods. In addition, 5 water quality parameters and 13 other physical conditions (such as basin area, river width, mean diameter of riverbed material, and number of river-crossing structures upstream and downstream) of each river section were considered as environmental variables. In case of Sagami River, 10 habitat variables among them were then selected based on their correlations to avoid multicollinearity. Finally, the best GLM was developed for each species based on Akaike's information criterion. As results, population densities of 16 fish species in Sagami River were modelled, and correlation coefficients between observed and calculated population densities for 10 species were more than 0.70. The key habitat factors for population density varied among fish species. Minimum discharge (MID) was found to be positively correlated to 9 among 16 fish species. For duration of high and low flows (DHF and DLF), longer DHF/DLF was corresponded to lower population density for 7/6 fish species, respectively, such as Rhinogobius kurodai and Plecoglossus altivelis altivelis. Among physical habitat conditions, sinuosity index (SI, the ratio between actual river section length and straight line length) seems to be the most important parameter for fish population density in Sagami River basin, since it affects 12 out of 16 fish species, followed by mean longitudinal slope (S) and number of downstream dams (NLD). Above results demonstrated the applicability of fish distribution model to provide quantitative information on flow conditions required to maintain fish population, which enabled us to evaluate and project ecological consequences of water resource management policy, such as flood management and water withdrawal.
An entropy-based method for determining the flow depth distribution in natural channels

NASA Astrophysics Data System (ADS)

Moramarco, Tommaso; Corato, Giovanni; Melone, Florisa; Singh, Vijay P.

2013-08-01

A methodology for determining the bathymetry of river cross-sections during floods by the sampling of surface flow velocity and existing low flow hydraulic data is developed . Similar to Chiu (1988) who proposed an entropy-based velocity distribution, the flow depth distribution in a cross-section of a natural channel is derived by entropy maximization. The depth distribution depends on one parameter, whose estimate is straightforward, and on the maximum flow depth. Applying to a velocity data set of five river gage sites, the method modeled the flow area observed during flow measurements and accurately assessed the corresponding discharge by coupling the flow depth distribution and the entropic relation between mean velocity and maximum velocity. The methodology unfolds a new perspective for flow monitoring by remote sensing, considering that the two main quantities on which the methodology is based, i.e., surface flow velocity and flow depth, might be potentially sensed by new sensors operating aboard an aircraft or satellite.
Revised Subsurface Stratigraphic Framework of the Fort Union and Wasatch Formations, Powder River Basin, Wyoming and Montana

USGS Publications Warehouse

Flores, Romeo M.; Spear, Brianne D.; Purchase, Peter A.; Gallagher, Craig M.

2010-01-01

Described in this report is an updated subsurface stratigraphic framework of the Paleocene Fort Union Formation and Eocene Wasatch Formation in the Powder River Basin (PRB) in Wyoming and Montana. This framework is graphically presented in 17 intersecting west-east and north-south cross sections across the basin. Also included are: (1) the dataset and all associated digital files and (2) digital files for all figures and table 1 suitable for large-format printing. The purpose of this U.S. Geological Survey (USGS) Open-File Report is to provide rapid dissemination and accessibility of the stratigraphic cross sections and related digital data to USGS customers, especially the U.S. Bureau of Land Management (BLM), to facilitate their modeling of the hydrostratigraphy of the PRB. This report contains a brief summary of the coal-bed correlations and database, and is part of a larger ongoing study that will be available in the near future.
The role of the exchanges through the Strait of Gibraltar on the budget of elements in the Western Mediterranean Sea: consequences of human-induced modifications.

PubMed

Gómez, Fernando

2003-06-01

The role of the Strait of Gibraltar on the exchanges of substances between Mediterranean Sea and the Atlantic Ocean is reviewed. The previous estimations have been recalculated by using a similar water flux and compared with the river and atmospheric inputs to the Western Mediterranean Sea. The man-induced changes in the dimensions of the Strait of Gibraltar increasing (planning the sill) or reducing of the cross-section by a total or partial dam are discussed. A total dam will control the sea-level rise in the Mediterranean Sea, but an annual increase of major nutrient concentrations of 1-2% could be expected, lower than the rate of increase of the river and atmospheric inputs in the Western Mediterranean Sea. The increase of the cross-section of the Strait by increasing the depth (planning) at the sill could compensate the increase of the external nutrient inputs.
Swath-altimetry measurements of the main stem Amazon River: measurement errors and hydraulic implications

NASA Astrophysics Data System (ADS)

Wilson, M. D.; Durand, M.; Jung, H. C.; Alsdorf, D.

2015-04-01

The Surface Water and Ocean Topography (SWOT) mission, scheduled for launch in 2020, will provide a step-change improvement in the measurement of terrestrial surface-water storage and dynamics. In particular, it will provide the first, routine two-dimensional measurements of water-surface elevations. In this paper, we aimed to (i) characterise and illustrate in two dimensions the errors which may be found in SWOT swath measurements of terrestrial surface water, (ii) simulate the spatio-temporal sampling scheme of SWOT for the Amazon, and (iii) assess the impact of each of these on estimates of water-surface slope and river discharge which may be obtained from SWOT imagery. We based our analysis on a virtual mission for a ~260 km reach of the central Amazon (Solimões) River, using a hydraulic model to provide water-surface elevations according to SWOT spatio-temporal sampling to which errors were added based on a two-dimensional height error spectrum derived from the SWOT design requirements. We thereby obtained water-surface elevation measurements for the Amazon main stem as may be observed by SWOT. Using these measurements, we derived estimates of river slope and discharge and compared them to those obtained directly from the hydraulic model. We found that cross-channel and along-reach averaging of SWOT measurements using reach lengths greater than 4 km for the Solimões and 7.5 km for Purus reduced the effect of systematic height errors, enabling discharge to be reproduced accurately from the water height, assuming known bathymetry and friction. Using cross-sectional averaging and 20 km reach lengths, results show Nash-Sutcliffe model efficiency values of 0.99 for the Solimões and 0.88 for the Purus, with 2.6 and 19.1 % average overall error in discharge, respectively. We extend the results to other rivers worldwide and infer that SWOT-derived discharge estimates may be more accurate for rivers with larger channel widths (permitting a greater level of cross-sectional averaging and the use of shorter reach lengths) and higher water-surface slopes (reducing the proportional impact of slope errors on discharge calculation).
Lateral and vertical heterogeneity of flow and suspended sediment characteristics during a dam flushing event, in high velocity conditions

NASA Astrophysics Data System (ADS)

Antoine, Germain; Cazilhac, Marine; Monnoyer, Quentin; Jodeau, Magali; Gratiot, Nicolas; Besnier, Anne-Laure; Henault, Fabien; Le Brun, Matthieu

2015-04-01

The dynamic of suspended sediments in highly turbulent and concentrated flow is an important issue to better predict the sediment propagation along mountain rivers. In such extreme environments, the spatial and temporal variability of hydraulic and sediment parameters are difficult to measure: the flow velocity and the suspended sediment concentration (SSC) could be high (respectively several m/s and g/l) and rapidly variable. Simple methods are commonly used to estimate water discharge and mean or punctual SSC. But no method has been used successfully in a mountain river to estimate during a whole event the spatial distribution of flow velocity and SSC, as well as sediment parameters like grain size or settling velocity into a river cross section. This leads to these two questions: in such conditions, can we calculate sediment fluxes with one sediment concentration measurement? How can we explain the spatial heterogeneity of sediment characteristics? In this study, we analyze sampled data from a very well instrumented river reach in the Northern French Alps: the Arc-Isère River system. This gravel-bed river system is characterized by large concentrations of fines sediments, coming from the highly erodible mountains around. To control the hydraulic, sedimentary and chemical parameters from the catchment head, several gauging stations have been established since 2006. Especially, several measurements are usually done during the flushing of the dams located on the upper part of the river. During the flushing event of June 2014, we instrumented the gauging station located just upstream the confluence between the Isere and the Arc River, at the outlet of the Arc River watershed. ADCP measurements have been performed to estimate the spatial distribution of the flow velocity (up to 3 m/s), and turbidimeters and automatic samplers have been used to estimate the spatial distribution of the SSC into the cross section (up to 6 g/l). These samples have been directly analyzed to measure the grain size distribution with a LISST Portable XR, as well as the settling velocities of the suspended sediments with the SCAF device (Wendling et al., 2013). Even if the measurements were difficult due to the flow conditions, some observations are relevant. For example, we observed a spatial heterogeneity of the settling velocity and the grain size of the suspended sediments into the cross section, whereas the SSC was almost homogeneous at the same time. In particular, these measurements show that the sediment flux can be calculated from the single turbidimeter located on the left bank. Moreover, the hydrodynamic measurements highlight the heterogeneity of the settling velocity due to the flow conditions. The first conclusions of these field measurements could be of great importance to assess numerical models, when they are used to estimate sediment deposits in river. V. WENDLING, N. GRATIOT, C. LEGOUT, I.G. DROPPO, A.J. MANNING, G. ANTOINE, H. MICHALLET, M. JODEAU : A rapid method for settling velocity and flocculation measurement within high suspended sediment concentration rivers. INTERCOH 2013, Gainesville, Florida.
Broadband measurements of aerosol extinction in the ultraviolet spectral region

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Flores, J. M.; Brock, C. A.; Brown, S. S.; Rudich, Y.

2013-04-01

Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross sections and complex refractive indices. We describe a new laboratory instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We determined aerosol extinction cross sections and directly observed Mie scattering resonances for aerosols that are purely scattering (polystyrene latex spheres and ammonium sulfate), slightly absorbing (Suwannee River fulvic acid), and strongly absorbing (nigrosin dye). We describe an approach for retrieving refractive indices as a function of wavelength from the measured extinction cross sections over the 360-420 nm wavelength region. The retrieved refractive indices for PSL and ammonium sulfate agree within uncertainty with the literature values for this spectral region. The refractive index determined for nigrosin is 1.78 (± 0.03) + 0.19 (± 0.08)i at 360 nm and 1.63 (± 0.03) + 0.21 (± 0.05)i at 420 nm. The refractive index determined for Suwannee River fulvic acid is 1.71 (± 0.02) + 0.07 (± 0.06)i at 360 nm and 1.66 (± 0.02) + 0.06 (± 0.04)i at 420 nm. These laboratory results support the potential for a field instrument capable of determining ambient aerosol optical extinction, average aerosol extinction cross section, and complex refractive index as a function of wavelength.

Broadband measurements of aerosol extinction in the ultraviolet spectral region

NASA Astrophysics Data System (ADS)

Washenfelder, R. A.; Flores, J. M.; Brock, C. A.; Brown, S. S.; Rudich, Y.

2013-01-01

Aerosols influence the Earth's radiative budget by scattering and absorbing incoming solar radiation. The optical properties of aerosols vary as a function of wavelength, but few measurements have reported the wavelength dependence of aerosol extinction cross-sections and complex refractive indices. We describe a new laboratory instrument to measure aerosol optical extinction as a function of wavelength, using cavity enhanced spectroscopy with a broadband light source. The instrument consists of two broadband channels which span the 360-390 and 385-420 nm spectral regions using two light emitting diodes (LED) and a grating spectrometer with charge-coupled device (CCD) detector. We determined aerosol extinction cross-sections and directly observed Mie scattering resonances for aerosols that are purely scattering (polystyrene latex spheres and ammonium sulfate), slightly absorbing (Suwannee River fulvic acid), and strongly absorbing (nigrosin dye). We describe an approach for retrieving refractive indices as a function of wavelength from the measured extinction cross-sections over the 360-420 nm wavelength region. The retrieved refractive indices for PSL and ammonium sulfate agree within uncertainty with literature values for this spectral region. The refractive index determined for nigrosin is 1.78 (±0.03) + 0.19 (±0.08) i at 360 nm and 1.53 (±0.03) + 0.21 (±0.05) i at 420 nm. The refractive index determined for Suwannee River fulvic acid is 1.71 (±0.02) + 0.07 (±0.06) i at 360 nm and 1.66 (±0.02) + 0.06 (±0.04) i at 420 nm. These laboratory results support the potential for a field instrument capable of determining ambient aerosol optical extinction, average aerosol extinction cross-section, and complex refractive index as a function of wavelength.
Metal poisons for criticality in waste streams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williamson, T.G.; Goslen, A.Q.

1996-12-31

Many of the wastes from processing fissile materials contain metals that may serve as neutron poisons. It would be advantageous to the criticality evaluation of these wastes to demonstrate that the poisons remain with the fissile materials and to demonstrate an always safe poison-to-fissile ratio. The first task, demonstrating that the materials stay together, is the job of the chemist; the second, calculating an always safe ratio, is an object of this paper. In an earlier study, the authors demonstrated safe ratios for iron, manganese, and chromium oxides to {sup 235}U. In these studies, the Hansen-Roach 16-group cross sections weremore » used with the Savannah River site code HRXN. Multiplication factors were computed, and safe ratios were defined such that the adjusted neutron multiplication factors (k values) were <0.95. These safe weight ratios were Fe:{sup 235}U - 77:1; Mn:{sup 235}U - 30:1; and Cr:{sup 235}U - 52:1. Palmer has shown that for certain mixtures of aluminum, iron, and zirconium with {sup 235}U, the computed infinite multiplication factors may differ by as much as 20% with different cross sections and processing systems. Parks et al. have further studied these mixtures and state, {open_quotes}...these metal/uranium mixtures are very sensitive to the metal cross-section data in the intermediate-energy range and the processing methods that are used.{close_quotes} They conclude with a call for more experimental data. The purpose of this study is to reexamine earlier work with cross sections and processing codes used at Westinghouse Savannah River Company today. This study will focus on {sup 235}U mixtures with iron, manganese and chromium. Sodium will be included in the list of poisons because it is abundant in many of the waste materials.« less
Regional Hydraulic Geometry Curves of the Northern Cascade Mountains, Chelan and King Counties, Washington State, USA

NASA Astrophysics Data System (ADS)

Gasperi, J. T.; McClung, J. M.; Hanson, D. L.

2006-12-01

The USDA-Natural Resources Conservation Service has developed regional hydraulic geometry curves relating drainage area to bankfull top width, mean depth and cross-sectional area for the east and west sides of the northern Cascade Mountains in Chelan and King Counties, Washington. NRCS surveyed 10 channel reaches with drainage areas from 1 to 1000 square miles within the Wenatchee River drainage of Chelan County and 10 channel reaches with drainage areas of 1 to 100 square miles within the Cedar and Green River drainages of King County. Selection criteria for stream reaches required a minimum of 20 years of USGS stream gage discharge records, unregulated flows and safe access. Survey data were collected with a Sokkia Total Station during low flow conditions from August 2004 to September 2005. NRCS measured a channel cross-section at each of the USGS stream gage sites and two or three additional cross-sections up and downstream. The authors also collected samples of bed material for gradation analysis and estimation of Manning's roughness coefficient, n. Bankfull elevations were estimated based on visual identification of field indicators and USGS flood discharges for the 50% exceedance probability event. Field data were evaluated with the Ohio DNR Reference Reach spreadsheet to determine bankfull top width, mean depth and cross-sectional area. We applied a simple linear regression to the data following USGS statistical methods to evaluate the closeness of fit between drainage area and bankfull channel dimensions. The resulting R2 values of 0.83 to 0.93 for the eastern Cascade data of Chelan County and 0.71 to 0.88 for the western Cascade data of King County indicate a close association between drainage area and bankfull channel dimensions for these two sets of data.
A systematic overview of the coincidences of river sinuosity changes and tectonically active structures in the Pannonian Basin

NASA Astrophysics Data System (ADS)

Petrovszki, Judit; Székely, Balázs; Timár, Gábor

2012-12-01

As tectonic movements change the valley slope (low-gradient reaches of valleys, in sedimentary basins), the alluvial rivers, as sensitive indicators, respond to these changes, by varying their courses to accommodate this forcing. In our study sinuosity values, a commonly used characteristic parameter to detect river pattern changes, were studied for the major rivers in the Pannonian Basin in order to reveal neotectonic influence on their planform shape. Our study area comprises the entire Pannonian Basin (330,000 km2) located in eastern Central-Europe, bounded by the Alps, Carpathians and Dinarides. The studied rivers were mostly in their natural meandering state before the main river regulations of the 19th century. The last quasi-natural, non-regulated river planforms were surveyed somewhat earlier, during the Second Military Survey of the Habsburg Empire. Using the digitized river sections of that survey, the sinuosities of the rivers were calculated with different sample section sizes ranging from 5 km to 80 km. Depending on the bank-full discharge, also a 'most representative' section size is given, which can be connected to the neotectonic activity. In total, the meandering reaches of 28 rivers were studied; their combined length is 7406 km. The places where the river sinuosity changed were compared to the structural lines of the "Atlas of the present-day geodynamics of the Pannonian Basin" (Horváth et al., 2006). 36 junctions along 26 structural lines were identified where the fault lines of this neotectonic map crossed the rivers. Across these points the mean sinuosity changed. Depending on the direction of the relative vertical movements, the sinuosity values increased or decreased. There were some points, where the sinuosity changed in an opposite way. Along these sections, the rivers belong to the range of unorganized meandering or there are lithological margins. Assuming that the rivers indicate on-going faulting accurately, some places were found, where positioning of the faults of the neotectonic map could be improved according to the sinuosity jumps. However, some significant sinuosity changes cannot be correlated to known faults. In these cases other factors may play a role (e.g., hydrological changes, increase of sediment discharge also can modify sinuosity). In order to clarify the origin of these changes seismic sections and other geodynamical information should be analyzed to prove or disprove tectonic relationship if hydrological reasons can be excluded.
Archeological Investigations at the Three Rivers Flood Control Project.

DTIC Science & Technology

1980-01-01

quartzite, jasper and chert-rich Uvalde gravels. In Pleistocene to Holocene times, valley incision ENVIRONMENTAL SETTING 6 and the topographic...fragments and a thick bi-,ace. The latter is elliptical in outline, plano -convex in cross section, and has sinuous edges. The dorsal surface retains
5. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL CUT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL CUT AND MORTARED STONE PIER AND ASSOCIATED STEEL SUPERSTRUCTURE (CENTER), AND CANTILEVERED NORTHERN TRUSS SECTION (RIGHT). FACING NORTHWEST. - Coverts Crossing Bridge, Spanning Mahoning River along Township Route 372 (Covert Road), New Castle, Lawrence County, PA
Water temperature, specific conductance, pH, and dissolved-oxygen concentrations in the lower White River and the Puyallup River estuary, Washington, August-October 2002

USGS Publications Warehouse

Ebbert, James C.

2003-01-01

The U.S. Geological Survey, Washington State Department of Ecology, and Puyallup Tribe of Indians monitored water temperature, specific conductance, pH, and dissolved-oxygen concentrations in the White River at river miles 4.9 and 1.8 from August until mid-October 2002. Water diverted from the White River upstream from the monitoring sites into Lake Tapps is returned to the river at river mile 3.6 between the two sites. The same characteristics were measured in a cross section of the Puyallup River estuary at river mile 1.5 during high and low tides in September 2002. In late August, maximum daily water temperatures in the White River of 21.1°C (degrees Celsius) at river mile 4.9 and 19.6°C at river mile 1.8 exceeded the water-quality standard of 18°C at both monitoring sites. In mid-September, maximum daily water temperatures at river mile 4.9 exceeded the standard on 5 days. From August 2-25, water temperatures at both monitoring sites were similar and little or no water was discharged from Lake Tapps to the White River. Increases in water temperature at river mile 1.8 in late September and early October were caused by the mixing of warmer water discharged from Lake Tapps with cooler water in the White River.Specific conductance in the White River usually was lower at river mile 1.8 than at river mile 4.9 because of mixing with water from Lake Tapps, which has a lower specific conductance. Maximum values of pH in the White River at river mile 4.9 often exceeded the upper limit of the water-quality standard, 8.5 pH units, from early September until mid-October, when turbidity decreased. The pH standard was not exceeded at river mile 1.8. Dissolved-oxygen concentrations in the White River were often lower at river mile 1.8 than at river mile 4.9 because of mixing with water discharged from Lake Tapps, which has lower dissolved-oxygen concentrations. The lowest concentration of dissolved oxygen observed was 7.9 mg/L (milligrams per liter) at river mile 1.8. The lower limit allowed by the water-quality standard is 8 mg/L. Concentrations of dissolved oxygen measured in a cross section of the Puyallup River estuary at high tide on September 12, 2002, ranged from 9.9 to 10.2 mg/L in fresh water at the surface and from 8.1 to 8.4 mg/L in salt water near the riverbed. These values were within limits set by Washington State water-quality standards for dissolved oxygen of 8 mg/L in fresh water and 6 mg/L in marine water.
Air-photo based change in channel width in the Minnesota River basin: Modes of adjustment and implications for sediment budget

NASA Astrophysics Data System (ADS)

Wesley Lauer, J.; Echterling, Caitlyn; Lenhart, Christian; Belmont, Patrick; Rausch, Rachel

2017-11-01

The Minnesota River and major tributaries have experienced large increases in discharge over the past century. Aerial photograph-based measurements of channel width were made for the 1938-2015 period at 16 multibend subreaches by digitizing the area between vegetation lines and dividing by centerline length. Results show considerable increases in width for the main stem (0.62 ± 0.10%/y) and major tributaries (0.31 ± 0.08%/y) but are inconclusive for smaller channels (width < 25 m). Width change for a 146.5-km reach of the lower Minnesota River between 1938 and 2008 is similar to that from the subreach-scale analysis. Widening was associated with lateral centerline movement and temporal change in at-a-station hydraulic geometry for water surface width, indicating that widening is associated with cross-sectional change and not simply upward movement of the vegetation line. Digital elevation model analysis and regional hydraulic geometry show that the main stem and larger tributaries account for the vast majority ( 85%) of bankfull channel volume. High-order channels are thus disproportionately responsible for sediment production through cross section enlargement, although floodplains or off-channel water bodies adjacent to these channels likely represent important sediment sinks. Because channel enlargement can play an important role in sediment production, it should be considered in sediment reduction strategies in the Minnesota River basin and carefully evaluated in other watersheds undergoing long-term increases in discharge.
Managed flood effects on beaver pond habitat in a desert riverine ecosystem, bill williams river, Arizona USA

USGS Publications Warehouse

Andersen, D.C.; Shafroth, P.B.; Pritekel, C.M.; O'Neill, M. W.

2011-01-01

The ecological effects of beaver in warm-desert streams are poorly documented, but potentially significant. For example, stream water and sediment budgets may be affected by increased evaporative losses and sediment retention in beaver ponds. We measured physical attributes of beaver pond and adjacent lotic habitats on a regulated Sonoran Desert stream, the Bill Williams River, after ???11 flood-free months in Spring 2007 and Spring 2008. Neither a predicted warming of surface water as it passed through a pond nor a reduction in dissolved oxygen in ponds was consistently observed, but bed sediment sorted to finest in ponds as expected. We observed a river segment-scale downstream rise in daily minimum stream temperature that may have been influenced by the series of ??100 beaver ponds present. Channel cross-sections surveyed before and after an experimental flood (peak flow 65 m3/s) showed net aggradation on nine of 13 cross-sections through ponds and three of seven through lotic reaches. Our results indicate that beaver affect riverine processes in warm deserts much as they do in other biomes. However, effects may be magnified in deserts through the potential for beaver to alter the stream thermal regime and water budget. ?? Society of Wetland Scientists 2011.
Morphological adjustments in a meandering reach of the middle Yangtze River caused by severe human activities

NASA Astrophysics Data System (ADS)

Zhou, Meirong; Xia, Junqiang; Lu, Jinyou; Deng, Shanshan; Lin, Fenfen

2017-05-01

In the past 50 years, the Shishou reach in the middle Yangtze River underwent significant channel evolution owing to the implementation of an artificial cutoff, the construction of bank revetment works and the operation of the Three Gorges Project (TGP). Based on the measured hydrological data and topographic data, the processes of channel evolution in this reach were investigated mainly from the adjustments in planform and cross-sectional geometries. The variation in planform geometry obtained in this study indicates that (i) the artificial cutoff at Zhongzhouzi caused the river regime to adjust drastically, with the mean rate of thalweg migration at reach scale of 42.0 m/a over the period 1966-1975; (ii) then the effect of this artificial cutoff reduced gradually, with the mean migration rate decreasing to < 30 m/a in 1975-1993, while it increased to > 40 m/a owing to the occurrence of high water levels in 1993-1998; and (iii) the average annual rate of thalweg migration decreased to 29.3 m/a because of the impacts of various bank protection engineering and the TGP operation during the period 2002-2015. However, remarkable thalweg migration processes still occurred in local regions after the TGP operation, which resulted in significant bankline migration in local reaches of Beimenkou, Shijiatai, and Tiaoxiankou. In addition, the adjustments of bankfull channel geometry were investigated at section and reach scales after the TGP operation. Calculated results show that lateral channel migration in this reach was restricted by various river regulation works and that channel evolution was mainly characterized by an increase in bankfull depth and cross-sectional area. Empirical relationships were developed between the reach-scale bankfull dimensions (depth and area), the bankfull widths at specified sections, and the previous 5-year average fluvial erosion intensity during flood seasons, with high correlation degrees between them being obtained.
A novel dendrochronological approach reveals drivers of carbon sequestration in tree species of riparian forests across spatiotemporal scales.

PubMed

Rieger, Isaak; Kowarik, Ingo; Cherubini, Paolo; Cierjacks, Arne

2017-01-01

Aboveground carbon (C) sequestration in trees is important in global C dynamics, but reliable techniques for its modeling in highly productive and heterogeneous ecosystems are limited. We applied an extended dendrochronological approach to disentangle the functioning of drivers from the atmosphere (temperature, precipitation), the lithosphere (sedimentation rate), the hydrosphere (groundwater table, river water level fluctuation), the biosphere (tree characteristics), and the anthroposphere (dike construction). Carbon sequestration in aboveground biomass of riparian Quercus robur L. and Fraxinus excelsior L. was modeled (1) over time using boosted regression tree analysis (BRT) on cross-datable trees characterized by equal annual growth ring patterns and (2) across space using a subsequent classification and regression tree analysis (CART) on cross-datable and not cross-datable trees. While C sequestration of cross-datable Q. robur responded to precipitation and temperature, cross-datable F. excelsior also responded to a low Danube river water level. However, CART revealed that C sequestration over time is governed by tree height and parameters that vary over space (magnitude of fluctuation in the groundwater table, vertical distance to mean river water level, and longitudinal distance to upstream end of the study area). Thus, a uniform response to climatic drivers of aboveground C sequestration in Q. robur was only detectable in trees of an intermediate height class and in taller trees (>21.8m) on sites where the groundwater table fluctuated little (≤0.9m). The detection of climatic drivers and the river water level in F. excelsior depended on sites at lower altitudes above the mean river water level (≤2.7m) and along a less dynamic downstream section of the study area. Our approach indicates unexploited opportunities of understanding the interplay of different environmental drivers in aboveground C sequestration. Results may support species-specific and locally adapted forest management plans to increase carbon dioxide sequestration from the atmosphere in trees. Copyright © 2016 Elsevier B.V. All rights reserved.
185. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

185. Photocopy of drawing, Twin Falls Canal Company, date unknown. MILNER DAM CROSS SECTION PLAN, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID
45. Photographic copy of the original construction drawing, 1934, by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

45. Photographic copy of the original construction drawing, 1934, by Sverdrup and Parcel, Consulting Engineers, from microfilm copy at Bridge Division, Missouri Highway and Transportation Department. Cross section--300-ft. span - Mark Twain Memorial Bridge, Spanning Mississippi River at US Route 36, Hannibal, Marion County, MO
Feeding the hungry river: Fluvial morphodynamics and the entrainment of artificially inserted sediment at the dammed river Isar, Eastern Alps, Germany

NASA Astrophysics Data System (ADS)

Heckmann, Tobias; Haas, Florian; Abel, Judith; Rimböck, Andreas; Becht, Michael

2017-08-01

Dams interrupt the sediment continuum in rivers by retaining the bedload; combined with flow diversion, bedload retention in tributaries and river engineering measures, this causes a bedload deficit leading to changes in river planform and morphodynamics, with potentially detrimental downstream effects. As part of the SedAlp joint project (Sediment management in Alpine basins: integrating sediment continuum, risk mitigation and hydropower), this study investigates changes within a section of the dammed river Isar between the Sylvenstein reservoir and the city of Bad Tölz. We use a multi-method approach on a range of spatial and temporal scales. First, we analysed historical maps and aerial photos to analyse river planform and landcover changes within the river corridor of the whole study area on a temporal scale of over 100 years. Results show that major changes occurred before the construction of the Sylvenstein reservoir, suggesting that present morphodynamics represent the reaction to different disturbances on different time scales. Second, changes in mean bed elevation of cross profiles regularly surveyed by the water authorities are analysed in light of artificial sediment insertion and floods; they are also used to estimate the sediment budget of river reaches between consecutive cross profiles. Results suggest stability and a slight tendency towards incision, especially near the Sylvenstein reservoir; further downstream, the sediment balance was positive. Third, we acquired multitemporal aerial photos using an unmanned aerial vehicle and generated high-resolution digital elevation models to show how sediment artificially inserted in the river corridor is entrained. Depending on the position of the artificial deposits in relation to the channel, the deposits are entrained during floods of different return periods.
Hydraulic Geometry and Microtopography of Tidal Freshwater Forested Wetlands and Implications for Restoration, Columbia River, U.S.A.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Diefenderfer, Heida L.; Coleman, Andre M.; Borde, Amy B.

2008-01-01

The hydrologic reconnection of tidal channels, riverine floodplains, and main stem channels are among responses by ecological restoration practitioners to the increasing fragmentation and land conversion occurring in coastal and riparian zones. Design standards and monitoring of such ecological restoration depend upon the characterization of reference sites that vary within and among regions. Few locales, such as the 235 km tidal portion of the Columbia River on the West Coast U.S.A., remain in which the reference conditions and restoration responses of tidal freshwater forested wetlands on temperate zone large river floodplains can be compared. This study developed hydraulic geometry relationshipsmore » for Picea sitchensis (Sitka spruce) dominated tidal forests (swamps) in the vicinity of Grays Bay on the Columbia River some 37 km from the Pacific Coast using field surveys and Light Detection and Ranging (LiDAR) data. Scaling relationships between catchment area and the parameters of channel cross-sectional area at outlet and total channel length were comparable to tidally influenced systems of San Francisco Bay and the United Kingdom. Dike breaching, culvert replacement, and tide gate replacement all affected channel cross-sectional geometry through changes in the frequency of over-marsh flows. Radiocarbon dating of buried wood provided evidence of changes in sedimentation rates associated with diking, and restoration trajectories may be confounded by historical subsidence behind dikes rendering topographical relationships with water level incomparable to reference conditions. At the same time, buried wood is influencing the development of channel morphology toward characteristics resembling reference conditions. Ecological restoration goals and practices in tidal forested wetland regions of large river floodplains should reflect the interactions of these controlling factors.« less
Estimates of bridge scour at two sites on the Virgin River, southeastern Nevada, using a sediment-transport model and historical geomorphic data

USGS Publications Warehouse

Hilmes, M.M.; Vaill, J.E.

1997-01-01

A bridge-scour study by the U.S. Geological Survey, in cooperation with the Nevada Department of Transportation, began in April 1996 to evaluate the Mesquite, Nevada, and Riverside, Nevada, bridges on the lower Virgin River using a sediment-transport model and historical geomorphic data. The BRIdge Stream Tube model for Alluvial River Simulation (BRI-STARS) was used to estimate bridge scour. The model was first calibrated using data for the Virgin River flood of March 12, 1995. Surveyed channel-geometry data were available at 11 cross sections for dates before and after the March 1995 flood to allow for evaluation of the model results. The model estimated the thalweg altitude within plus or minus 1 meter at 10 of the 11 cross sections. The calibrated model then was used to estimate the contraction, channel, pier, and total scour for synthesized hydrographs for 100- and 500-year floods at the two bridge sites. The estimated maximum total scour at the Mesquite bridge was 1.30 meters for the 100-year flood and 1.32 meters for the 500-year flood. The maximum total scour at the Riverside bridge was 1.90 meters for the 100-year flood and 2.01 meters for the 500-year flood. General scour was evaluated using stage-discharge relations at nearby streamflow-gaging stations, 1993-95 channel-geometry data, and channel-geometry data for the 100- and 500-year floods. On the basis of stage and discharge at the Littlefield, Arizona, gaging station, no long-term trend in aggradation or degradation was found. However, several cycles of aggradation and degradation had occurred during the period of record; the difference between the highest and lowest stage was 0.87 meter for a chosen low-flow discharge of 5.66 cubic meters per second for 1929-95. The value of 0.87 meter is probably the best estimate of general scour. The cross sections had an average scour depth of 0.07 meter between 1993 and 1994 and 0.16 meter between 1994 and 1995. The model simulated little general scour for the 100- and 500-year floods at the cross sections and did not give a good estimate of general scour, probably because the duration (days) of the floods used in the model was relatively short when compared with the duration (months or years) of geomorphic processes that influence long-term aggradation or degradation. Historical geomorphic changes of the Virgin River at the bridge sites and the causes of those changes were documented using aerial photographs from 1938-95 and other historical information. The Virgin River has become narrower and more sinuous through time, the vegetation on the flood plain has increased, and the channel has shifted laterally many times. The processes associated with these channel changes were found to be long-term changes in precipitation and streamflow; the duration, magnitude, and timing of floods; sediment-transport characteristics; channel avulsion; changes in density of vegetation; and anthropogenic influences.
Summary of Flow Loss between Selected Cross Sections on the Rio Grande in and near Albuquerque, New Mexico

USGS Publications Warehouse

Veenhuis, Jack E.

2002-01-01

The upper middle Rio Grande Basin, as defined by the U.S. Army Corps of Engineers, extends from the headwaters of the Rio Grande in southwestern Colorado to Fort Quitman, Texas. Most of the basin has a semiarid climate typical of the southwestern United States. This climate drives a highly variable streamflow regime that contributes to the complexity of water management in the basin. Currently, rapid population growth in the basin has resulted in increasing demands on the hydrologic system. Water management decisions have become increasingly complex because of the broad range of interests and issues. For these reasons, the U.S. Geological Survey, in cooperation with the City of Albuquerque, New Mexico, conducted paired flow measurements at two cross sections to determine cross-sectional loss in the Albuquerque reach of the Rio Grande. This report statistically summarizes flow losses in the Albuquerque reach of the Rio Grande during the winter nonirrigation season from December 1996 to February 2000. The two previous flow-loss investigations are statistically summarized. Daily mean flow losses are calculated for the winter nonirrigation season using daily mean flows at three selected Rio Grande streamflow-gaging stations.For the winter nonirrigation season cross-sectional measurements (1996-2000), an average of 210 cubic feet per second was returned to the river between the measurement sites, of which 165 cubic feet per second was intercepted by riverside drains along the 21.9-mile reach from the Rio Grande near Bernalillo to the Rio Grande at Rio Bravo Bridge streamflow-gaging stations. Total cross-sectional losses in this reach averaged about 90 cubic feet per second. Regression equations were determined for estimating downstream total outflow from upstream total inflow for all three paired measurement studies. Regression equations relating the three daily mean flow recording stations also were determined. In each succeeding study, additional outside variables were controlled, which provided more accurate flow-loss measurements. Regression-equation losses between measurement cross sections ranged from 1.9 to 7.9 percent during the nonirrigation season and from about 5.9 to 6.4 percent during the irrigation season. Mean and median loss by reach length for all three daily mean flow stations and all three cross-sectional measurement reaches showed consistent flow loss per mile by season with allowance for nonideal river conditions for the initial measurement studies. Unsteady measurement conditions were reflected in the regression equation mean-square errors and ultimately in the change in daily mean discharge at the Rio Grande at Albuquerque gaging station during the measurement periods.
Aerial view of the entire bridge crossing the Tennessee River ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Aerial view of the entire bridge crossing the Tennessee River looking up river. The swing bridge, when open, permits river navigational traffic to ply the river. Construction of a replacement bridge, to be located 93.27 feet down river, has now started. - Bridgeport Swing Span Bridge, Spanning Tennessee River, Bridgeport, Jackson County, AL
Preliminary Stratigraphic Cross Sections of Oil Shale in the Eocene Green River Formation, Uinta Basin, Utah

USGS Publications Warehouse

Dyni, John R.

2008-01-01

Oil shale units in the Eocene Green River Formation are shown on two east-west stratigraphic sections across the Uinta Basin in northeastern Utah. Several units have potential value for recovery of shale oil, especially the Mahogany oil shale zone, which is a high grade oil shale that can be traced across most of the Uinta Basin and into the Piceance Basin in northwestern Colorado. Many thin medium to high grade oil shale beds above the Mahogany zone can also be traced for many miles across the basin. Several units below the Mahogany that have slow velocities on sonic logs may be low grade oil shale. These may have value as a source for shale gas.
Numerical Model Study of the Tuscarawas River below Dover Dam, Ohio

DTIC Science & Technology

2009-09-01

chl.erdc.usace.army.mil/sms). Cross-sections from a ERDC/CHL TR-09-17 7 HEC - RAS model provided by the district, along with aerial photographs for proper alignment...ER D C/ CH L TR -0 9 -1 7 Numerical Model Study of the Tuscarawas River below Dover Dam, Ohio Richard L. Stockstill and Jane M. Vaughan...September 2009 C oa st al a n d H yd ra u lic s La b or at or y Approved for public release; distribution is unlimited. ERDC/CHL TR-09

Analysing the meandering rivers responses to the slope-changes, depending on their bankfull discharge - Case study in the Pannonian Basin

NASA Astrophysics Data System (ADS)

Petrovszki, Judit; Timár, Gábor; Molnár, Gábor

2014-05-01

The multi-variable connection between the channel slope, bankfull discharge and sinuosity values were analysed to get a mathematical formula, which describes the responses of the rivers, and gives the probable sinuosity values for every slope and discharge values. Timár (2003) merged two planar diagrams into a quasi 3D graph. One of them displayed how the river pattern changes, according to the slope and bankfull discharge values (Leopold and Wolmann, 1957; Ackers and Charlton, 1971); the other based on flume experiments, and gives a connection between the slope and sinuosity (Schumm and Khan, 1972). The result graph suggests that the slope-sinuosity connection also works along the natural rivers, for every discharge values. The aim of this work was to prove this relation, and describe it numerically. The sinuosity values were calculated along the natural, meandering river beds, using historical maps (2nd Military Survey of the Habsburg Empire, from the 19th century). The available slope and discharge values were imported from a database measured after the main river control works, at the beginning of the 20th century (Viczián, 1905). Analysing the reports of the river control works, the natural slope could be computed for every river sections. The mean discharges were also converted to bankfull discharges. Neither long time series, nor cross sectional areas were obtainable, so other method was used to generate the bankfull discharge. After the above mentioned corrections a quadratic polynomial surface was fitted onto these points with least squares regression. The cross section of this surface follows the theoretical slope-sinuosity graph, verifying that the flume experiments and natural rivers behave similarly. The differences between the fitted surface and the original points were caused by other river parameters, which also affect the natural rivers (e.g. the sediment discharge). Furthermore, this graph confirms the connection between the slope and sinuosity, so the sinuosity is a useable parameter to detect the changing slope. The research is made in the frame of project OTKA-NK83400 (SourceSink Hungary). The European Union and the European Social Fund also have provided financial support to the project under the grant agreement no. TÁMOP 4.2.1./B-09/1/KMR-2010-0003. References: Ackers, P., Charlton, F. G. (1971): The slope and resistance of small meandering channels. Inst. Civil Engineers Proc. Supp. XV, Paper 73625. Leopold, L. B., Wolman, M. G. (1957): River chanel patterns; braided, meandering and straight. USGS Prof. Paper 282B: 1-73. Schumm, S. A., Khan, H. R. (1972): Experimental study of channel patterns. Geol. Soc. Am. Bull. 83:1755-1770. Timár, G. (2003): Controls on channel sinuosity changes: a case study of the Tisza River, the Great Hungarian Plain. Quaternary Science Reviews 22: 2199-2207. Viczián E. (1905): Magyarország vízierői. Pallas, Budapest, 349 o.
Suspended sediments of the modern Amazon and Orinoco rivers

USGS Publications Warehouse

Meade, R.H.

1994-01-01

The Amazon and Orinoco Rivers are massive transcontinental conveyance systems for suspended sediment. They derive about 90% of their sediment from the Andes that support their western headwaters, transport it for thousands of kilometers across the breadth of the continent and deposit it in the coastal zones of the Atlantic. At their points of maximum suspended-sediment discharge, the Amazon transports an average of 1100-1300 ?? 106 tons per year and the Orinoco transports about 150 ?? 106 tons per year. Relations of sediment discharge to water discharge are complicated by unusual patterns of seasonal storage and remobilization, increased storage and reduced transport of sediment in the middle Orinoco during periods of peak water discharge, and storage of suspended sediment in the lower Amazon during rising discharge and resuspension during falling discharge. Spatial distributions of suspended sediment in cross-sections of both rivers are typically heterogeneous, not only in the vertical sense but also in the lateral. The cross-channel mixing of tributary inputs into the mainstem waters is a slow process that requires several hundred kilometers of downriver transport to complete. Considerable fine-grained sediment is exchanged between rivers and floodplains by the combination of overbank deposition and bank erosion. ?? 1994.
Determination of the 100-year flood plain on Upper Three Runs and selected tributaries, and the Savannah River at the Savannah River site, South Carolina, 1995

USGS Publications Warehouse

Lanier, T.H.

1996-01-01

The 100-year flood plain was determined for Upper Three Runs, its tributaries, and the part of the Savannah River that borders the Savannah River Site. The results are provided in tabular and graphical formats. The 100-year flood-plain maps and flood profiles provide water-resource managers of the Savannah River Site with a technical basis for making flood-plain management decisions that could minimize future flood problems and provide a basis for designing and constructing drainage structures along roadways. A hydrologic analysis was made to estimate the 100-year recurrence- interval flow for Upper Three Runs and its tributaries. The analysis showed that the well-drained, sandy soils in the head waters of Upper Three Runs reduce the high flows in the stream; therefore, the South Carolina upper Coastal Plain regional-rural-regression equation does not apply for Upper Three Runs. Conse- quently, a relation was established for 100-year recurrence-interval flow and drainage area using streamflow data from U.S. Geological Survey gaging stations on Upper Three Runs. This relation was used to compute 100-year recurrence-interval flows at selected points along the stream. The regional regression equations were applicable for the tributaries to Upper Three Runs, because the soil types in the drainage basins of the tributaries resemble those normally occurring in upper Coastal Plain basins. This was verified by analysis of the flood-frequency data collected from U.S. Geological Survey gaging station 02197342 on Fourmile Branch. Cross sections were surveyed throughout each reach, and other pertinent data such as flow resistance and land-use were col- lected. The surveyed cross sections and computed 100-year recurrence-interval flows were used in a step-backwater model to compute the 100-year flood profile for Upper Three Runs and its tributaries. The profiles were used to delineate the 100-year flood plain on topographic maps. The Savannah River forms the southwestern border of the Savannah River Site. Data from previously published reports were used to delineate the 100-year flood plain for the Savannah River from the downstream site boundary at the mouth of Lower Three Runs at river mile 125 to the upstream site boundary at river mile 163.
A New Approach to Scaling Channel Width in Bedrock Rivers and its Implications for Modeling Fluvial Incision

NASA Astrophysics Data System (ADS)

Finnegan, N. J.; Roe, G.; Montgomery, D. R.; Hallet, B.

2004-12-01

The fundamental role of bedrock channel incision on the evolution of mountainous topography has become a central concept in tectonic geomorphology over the past decade. During this time the stream power model of bedrock river incision has immerged as a valuable tool for exploring the dynamics of bedrock river incision in time and space. In most stream power analyses, river channel width--a necessary ingredient for calculating power or shear stress per unit of bed area--is assumed to scale solely with discharge. However, recent field-based studies provide evidence for the alternative view that channel width varies locally, much like channel slope does, in association with spatial changes in rock uplift rate and erodibility. This suggests that simple scaling relations between width and discharge, and hence estimates of stream power, don't apply in regions where rock uplift and erodibility vary spatially. It also highlights the need for an alternative to the traditional assumptions of hydraulic geometry to further investigation of the coupling between bedrock river incision and tectonic processes. Based on Manning's equation, basic mass conservation principles, and an assumption of self-similarity for channel cross sections, we present a new relation for scaling the steady-state width of bedrock river channels as a function of discharge (Q), channel slope (S), and roughness (Ks): W \\propto Q3/8S-3/16Ks1/16. In longitudinally simple, uniform-concavity rivers from the King Range in coastal Northern California, the model emulates traditional width-discharge relations that scale channel width with the square root of discharge. More significantly, our relation describes river width trends for the Yarlung Tsangpo in SE Tibet and the Wenatchee River in the Washington Cascades, both rivers that narrow considerably as they incise terrain with spatially varied rock uplift rates and/or lithology. We suggest that much of observed channel width variability is a simple consequence of the tendency for water to flow faster in steeper reaches and therefore maintain smaller channel cross sections. We demonstrate that using conventional scaling relations for bedrock channel width can significantly underestimate stream power variability in bedrock channels, and that our model improves estimates of spatial patterns of bedrock incision rates.
Flood characteristics for the New River in the New River Gorge National River, West Virginia

USGS Publications Warehouse

Wiley, J.B.; Cunningham, M.K.

1994-01-01

The frequency and magnitude of flooding of the New River in the New River Gorge National River was studied. A steady-state, one-dimensional flow model was applied to the study reach. Rating curves, cross sections, and Manning's roughness coefficients that were used are presented in this report. Manning's roughness coefficients were evaluated by comparing computed elevations (from application of the steady-state, one-dimensional flow model) to rated elevations at U.S. Geological Survey (USGS) streamflow-gaging stations and miscellaneous-rating sites. Manning's roughness coefficients ranged from 0.030 to 0.075 and varied with hydraulic depth. The 2-, 25-, and 100-year flood discharges were esti- mated on the basis of information from flood- insurance studies of Summers County, Fayette County, and the city of Hinton, and flood-frequency analysis of discharge records for the USGS streamflow-gaging stations at Hinton and Thurmond. The 100-year discharge ranged from 107,000 cubic feet per second at Hinton to 150,000 cubic feet per second at Fayette.
Hydroecological monitoring in the headwaters of the Volga River

NASA Astrophysics Data System (ADS)

Kuzovlev, Viacheslav V.; Zhenikov, Yuri N.; Zhenikov, Kyrill Y.; Shaporenko, Sergey I.; Haun, Stefan; Füreder, Leopold; Schletterer, Martin

2016-04-01

Europe's largest river, the Volga (3551 km), has experienced multiple stressors from human activities (i.e. the Volga Basin comprises about 40 % of the Russian population, 45 % of the country's industry and more than 50 % of its agriculture). During the research expedition "Upper Volga 2005" an assessment of hydrological, limnochemical and biological parameters was carried out by scientists from the Russian Federation and from Austria. The extensive sampling in 2005 showed that the free-flowing section of the Volga River, located upstream of Tver, represents conditions which are either reference or least disturbed - thus it can be considered as a refugial system for freshwater biota of the European lowlands. Subsequently three stretches in the headwaters of the Volga River (Rzhev, Staritsa, Tver) were selected for the monitoring programme "REFCOND_VOLGA", which is in operation since 2006. These locations correspond also with the sampling sites of ROSHYDROMET, i.e. at Tver physic-chemical samples are taken monthly and at Rzhev samples are taken in the main hydrological periods. The laboratory ship "ROSHYDROMET 11" conducted monthly cruises between Tver and Kalyazin (Ivankovskoye and Uglichskoye reservoirs on Volga) in the headwaters during the navigation period (May - October). This also includes measurements with ADCP, which further allow the analyses of the spatial distribution of the suspended solids within cross sections. In addition sediment fluxes were derived by using the acoustic backscatter signal strength from the acoustic current Doppler profiler (ADCP). We exemplify at the monitoring sites the spatial distribution of different sediments, i.e. choriotope types, according the longitudinal profile of the river. We show that it is highly influenced by morphodynamics in the different river sections and this corresponds with the zoobenthos fauna accordingly. This interdisciplinary approach, including sediment conditions, limnochemistry, hydrology and hydrobiology, leads to a hydro-ecological reference for European lowland rivers.
Interactions between river channel processes and riparian vegetation - an example from the Lužnice River, Czech Republic

NASA Astrophysics Data System (ADS)

Krejci, Lukas; Macka, Zdenek

2010-05-01

Riparian vegetation responds to hydrogemorphic processes and environmental changes and also controls these processes. Our study focuses on the interactions between woody riparian vegetation (live and dead trees) and river channel morphology on the example of three 1 km long reaches of the Lužnice River in southern Czech Republic. Here, we propose that despite spatial proximity, identical hydrological and sedimentological controls, three river reaches have different geomorphology due to varying character of riparian woody vegetation and different character and abundance of large in-stream wood (LW). Upstream, middle and downstream reaches vary markedly in channel dimensions (width, depth) and the present day rate of lateral erosion. Three reaches also show the different in-stream wood loads which are dependent mainly on the character of the riparian vegetation, and on the lateral activity of the channel. The highest wood load was recorded at the downstream reach with 102,162 m3/ha, the lowest at the middle reach 37,041 m3/ha, the upstream reach has load 81,370 m3/ha. Upper reach woody vegetation is the mixture of willow, alder, chokecherry and oak. The reach is only slightly sinuous with the moderate rate of incision and lateral erosion. The channel width and depth are 13 m and 2,1 m respectively, the mean cross section area is 27,3 m2. Erosion in the reach is slightly enhanced by the river training works upstream (canalisation, weir construction). Middle reach woody vegetation mostly consist of willow. Tree-tops often incline into the channel, thus, dissipating effectively the energy of the river flow. The reach is moderately sinuous and rather laterally stable. The channel width and depth are 10 m and 2,5 m respectively, the mean cross section area is 25 m2. The reach approximates the natural condition of the pristine river. The impact of river training works is minor only with the road bridge upstream. This reach in the most natural condition shows the lowest in-stream wood load and lowest rate of the present day bank erosion. Downstream reach woody vegetation is discontinuous, alternating with pastures. Riparian trees are the mixture of poplar, willow, alder and oak. The reach is highly sinuous with distinct meanders and laterally very dynamic. The channel width and depth are 15 m and 3,7 m respectively, the mean cross section area is 55,5 m2. The highest bank erosion was noted at the locations with pastures. The specific feature of this reach are fossil oak logs, which are exhumed from the alluvial sediments by the rapid lateral erosion. The enhanced incision and lateral erosion is the combined effect of riparian forest clearance and river training works (canalisation) downstream. The planform changes of the river since 1952 have been studied by analysis of the aerial images. It was derived that floodplain area of 12 450 m2, 16 318 m2 and 20 687 m2 was eroded, of which 10 465 m2, 8496 m2 and 10 733 m2 was wooded land at the upstream, middle and downstream reaches. We estimated that this rate of bank erosion delivered 644, 510 and 628 trees to the river channel since 1952. These numbers represent 390%, 1130% and 285% of the present day number of LW pieces in the river channel. Approximate turnover rates of LW can be estimated from these data. Present day rate of bank erosion and LW input is monitored at selected concave banks by repeated geodetic surveying. The Lužnice River has a sandy bed and LW modifies bed and bank morphology profoundly. We found that 33%, 29% and 36% of LW pieces caused localized erosion (pool formation) and 37%, 24% and 21 % caused local deposition at upstream, middle and downstream river reaches. The research was supported by Czech Science Foundation, grant no. 205/08/0926.
Investigations of Sediment Transportation, Middle Loup River at Dunning, Nebraska: With Application of Data from Turbulence Flume

USGS Publications Warehouse

Hubbell, David Wellington; Matejka, Donald Quintin

1959-01-01

An investigation of fluvial sediments of the Middle Loup River at Dunning, Nebr., was begun in 1946 and expanded in 1949 to provide information on sediment transportation. Construction of an artificial turbulence flume at which the total sediment discharge of the Middle Loup River at Dunning, Nebr., could be measured with suspended-sediment sampling equipment was completed in 1949. Since that time. measurements have been made at the turbulence flume and at several selected sections in a reach upstream and downstream from the flume. The Middle Loup River upstream from Dunning traverses the sandhills region of north-central Nebraska and has a drainage area of approximately 1,760 square miles. The sandhills are underlain by the Ogallala formation of Tertiary age and are mantled by loess and dune sand. The topography is characterized by northwest-trending sand dunes, which are stabilized by grass cover. The valley floor upstream from Dunning is generally about half a mile wide, is about 80 feet lower than the uplands, and is composed of sand that was mostly stream deposited. The channel is defined by low banks. Bank erosion is prevalent and is the source of most of the sediment load. The flow originates mostly from ground-water accretion and varies between about 200 and 600 cfs (cubic feet per second). Measured suspended-sediment loads vary from about 200 to 2,000 tons per day, of which about 20 percent is finer than 0.062 millimeter and 100 percent is finer than 0.50 millimeter. Total sediment discharges vary from about 500 to 3,500 tons per day, of which about 10 percent is finer than 0.062 millimeter, about 90 percent is finer than 0.50 millimeter, and about 98 percent is finer than 2.0 millimeters. The measured suspended-sediment discharge in the reach near Dunning averages about one-half of the total sediment discharge as measured at the turbulence flume. This report contains information collected during the period October 1, 1948, to September 30, 1952. The information includes sediment discharges; particle-size analyses of total load, of measured suspended sediment, and of bed material; water discharges and other hydraulic data for the turbulence flume and the selected sections. Sediment discharges have been computed with several different formulas, and insofar as possible, each computed load has been compared with data from the turbulence flume. Sediment discharges computed with the Einstein procedure did not agree well, in general, with comparable measured loads. However, a satisfactory representative cross section for the reach could not be determined with the cross sections that were selected for this investigation. If the computed cross section was narrower and deeper than a representative cross section for the reach, computed loads were high; and if the computed cross section was wider and shallower than a representative cross section for the reach, computed loads were low. Total sediment discharges computed with the modified Einstein procedure compared very well with the loads of individual size ranges and the measured total loads at the turbulence flume. Sediment discharges computed with the Straub equation averaged about twice the measured total sediment discharge at the turbulence flume. Bed-load discharges computed with the Kalinske equation were of about the right magnitude; however, high computed loads were associated with low total loads, low unmeasured loads, and low concentrations of measured suspended sediment coarser than 0.125 millimeter. Bed-load discharges computed with the Schoklitsch equation seemed somewhat high; about one-third of the computed loads were slightly higher than comparable unmeasured loads. Although, in general, high computed discharges with the Schoklitsch equation were associated with high measured total loads, high unmeasured loads, and high concentrations of measured suspended sediment coarser than 0.125 millimeter, the trend was not consistent. Bed-load discharges computed
Revised geologic cross sections of parts of the Colorado, White River, and Death Valley regional groundwater flow systems, Nevada, Utah, and Arizona

USGS Publications Warehouse

Page, William R.; Scheirer, Daniel S.; Langenheim, V.E.; Berger, Mary A.

2006-01-01

This report presents revisions to parts of seven of the ten cross sections originally published in U.S. Geological Survey Open-File Report 2006-1040. The revisions were necessary to correct errors in some of the original cross sections, and to show new parts of several sections that were extended and (or) appended to the original section profiles. Revisions were made to cross sections C-C', D-D', E-E', F-F', G-G', I-I', and J-J', and the parts of the sections revised or extended are highlighted below the sections on plate 1 by red brackets and the word "revised," or "extended." Sections not listed above, as well as the interpretive text and figures, are generally unchanged from the original report. Cross section C-C' includes revisions in the east Mormon Mountains in the east part of the section; D-D' includes revisions in the Mormon Mesa area in the east part of the section; E-E' includes revisions in the Muddy Mountains in the east part of the section; F-F' includes revisions from the Muddy Mountains to the south Virgin Mountains in the east part of the section; and J-J' includes some revisions from the east Mormon Mountains to the Virgin Mountains. The east end of G-G' was extended about 16 km from the Black Mountains to the southern Virgin Mountains, and the northern end of I-I' was extended about 45 km from the Muddy Mountains to the Mormon Mountains, and revisions were made in the Muddy Mountains part of the original section. This report contains 10 interpretive cross sections and an integrated text describing the geology of parts of the Colorado, White River, and Death Valley regional groundwater flow systems in Nevada, Utah, and Arizona. The primary purpose of the report is to provide geologic framework data for input into a numerical groundwater model. Therefore, the stratigraphic and structural summaries are written in a hydrogeologic context. The oldest rocks (basement) are Early Proterozoic metamorphic and intrusive crystalline rocks that are considered confining units because of their low permeability. Late Proterozoic to Lower Cambrian clastic units overlie the crystalline rocks and are also considered confining units within the regional flow systems. Above the clastic units are Middle Cambrian to Lower Permian carbonate rocks that are the primary aquifers in the flow systems. The Middle Cambrian to Lower Permian carbonate rocks are overlain by a sequence of mainly clastic rocks of late Paleozoic to Mesozoic age that are mostly considered confining units, but they may be permeable where faulted. Tertiary volcanic and plutonic rocks are exposed in the northern and southern parts of the study area. In the Clover and Delamar Mountains, these rocks are highly deformed by north- and northwest-striking normal and strike-slip faults that are probably important conduits in transmitting groundwater from the basins in the northern Colorado and White River flow systems to basins in the southern part of the flow systems. The youngest rocks in the region are Tertiary to Quaternary basin-fill deposits. These rocks consist of middle to late Tertiary sediments consisting of limestone, conglomerate, sandstone, tuff, and gypsum, and younger Quaternary surficial units consisting of alluvium, colluvium, playa deposits, and eolian deposits. Basin-fill deposits are both aquifers and aquitards. The rocks in the study area were complexly deformed by episodes of Mesozoic compression and Cenozoic extensional tectonism. Some Cretaceous thrust faults and folds of the Sevier orogenic belt form duplex zones and define areas of maximum thickness for the Paleozoic carbonate rocks. Cenozoic faults are important because they are the primary structures that control groundwater flow in the regional flow systems.
Conservation biology of the Cross River gorilla (Gorilla gorilla diehli)

NASA Astrophysics Data System (ADS)

Bergl, Richard Alexander

The Cross River gorilla (Gorilla gorilla diehli), a recently revived fourth subspecies of gorilla, is the most endangered and poorly studied ape taxon. Only about 300 Cross River gorillas remain and these gorillas occur in at least eleven different localities. This dissertation presents a population-wide assessment of threats to this population based on molecular genetic data, satellite imagery and demographic modeling. I used DNA extracted from non-invasively collected fecal samples to amplify eleven microsatellite loci for population genetic analysis. Microsatellite data suggested that a complex population structure is present in the Cross River gorilla, with three genetically identifiable subpopulations present. Though levels of gene flow between certain subpopulations were low, there is evidence that reproductive contact persists between many of the subpopulations. The genetic data also demonstrate that levels of diversity in the Cross River population are not evenly distributed across subpopulations, and that one subpopulation has higher levels of variability than the others. In a genus-wide comparison, levels of genetic diversity in the Cross River gorilla were comparable to those of the similarly small populations of the mountain gorilla ( Gorilla beringei beringei) in Bwindi and the Virunga volcanoes, but showed lower levels of diversity than a sample from a large, continuous population of Gorilla gorilla gorilla at Mondika, Central African Republic. Genetic data also showed strong evidence of a population bottleneck in the Cross River gorilla, but not in the other three gorilla populations examined. I used analysis of remotely-sensed data from the Landsat satellite to assess the extent and pattern of land cover distribution across the Cross River gorilla's range. Considerable potential gorilla habitat remains within the range of the Cross River gorilla and each gorilla locality is at least tenuously connected by forest. Finally, I developed a model-based population viability analysis for the Cross River gorilla. Demographic modeling suggested that both population structure and variables associated with female reproductive output most influence population growth in the Cross River gorilla. Taken together, the results of my study are encouraging for the conservation of the Cross River gorilla population, and highlight the resilience of these animals in the face of human activities. Conservation efforts should promote connectivity between gorilla localities and foster the growth of their population. The methods I applied could provide useful insights into patterns of population structure and migration for a wide range of animal taxa.
A Televised Entertainment-Education Drama to Promote Positive Discussion about Organ Donation

ERIC Educational Resources Information Center

Khalil, Georges E.; Rintamaki, Lance S.

2014-01-01

This article investigates pathways between the exposure to an entertainment-education (E-E) television drama called "Three Rivers" and positive discussion of organ donation among viewers of the drama in the United States. A cross-sectional survey was conducted using an online advertising for a period of one week. Survey participants…
Two-dimensional hydrologic modeling to evaluate aquatic habitat conditions

Treesearch

Pamela Edwards; Frederica Wood; Michael Little; Peter Vila; Peter Vila

2006-01-01

We describe the modeling and mapping procedures used to examine aquatic habitat conditions and habitat suitability of a small river in north- central West Virginia where fish survival and reproduction in specific reaches are poor. The study includes: (1) surveying cross sections of streambed reaches and measuring discharges and corresponding water-surface elevations,...
194. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

194. Photocopy of drawing, Twin Falls Canal Company, date unknown. PROFILE AND GATE PLAN, NORTH ISLAND CROSS SECTION OF DAM, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID
Questa Baseline and Pre-Mining Ground-Water Quality Investigation. 24. Seismic Refraction Tomography for Volume Analysis of Saturated Alluvium in the Straight Creek Drainage and Its Confluence With Red River, Taos County, New Mexico

USGS Publications Warehouse

Powers, Michael H.; Burton, Bethany L.

2007-01-01

As part of a research effort directed by the New Mexico Environment Department to determine pre-mining water quality of the Red River at a molybdenum mining site in northern New Mexico, we used seismic refraction tomography to create subsurface compressional-wave velocity images along six lines that crossed the Straight Creek drainage and three that crossed the valley of Red River. Field work was performed in June 2002 (lines 1-4) and September 2003 (lines 5-9). We interpreted the images to determine depths to the water table and to the top of bedrock. Depths to water and bedrock in boreholes near the lines correlate well with our interpretations based on seismic data. In general, the images suggest that the alluvium in this area has a trapezoidal cross section. Using a U.S. Geological Survey digital elevation model grid of surface elevations of this region and the interpreted elevations to water table and bedrock obtained from the seismic data, we generated new models of the shape of the buried bedrock surface and the water table through surface interpolation and extrapolation. Then, using elevation differences between the two grids, we calculated volumes of dry and wet alluvium in the two drainages. The Red River alluvium is about 51 percent saturated, whereas the much smaller volume of alluvium in the tributary Straight Creek is only about 18 percent saturated. When combined with average ground-water velocity values, the information we present can be used to determine discharge of Straight Creek into Red River relative to the total discharge of Red River moving past Straight Creek. This information will contribute to more accurate models of ground-water flow, which are needed to determine the pre-mining water quality in the Red River.
On mass and momentum conservation in the variable-parameter Muskingum method

NASA Astrophysics Data System (ADS)

Reggiani, Paolo; Todini, Ezio; Meißner, Dennis

2016-12-01

In this paper we investigate mass and momentum conservation in one-dimensional routing models. To this end we formulate the conservation equations for a finite-dimensional reach and compute individual terms using three standard Saint-Venant (SV) solvers: SOBEK, HEC-RAS and MIKE11. We also employ two different variable-parameter Muskingum (VPM) formulations: the classical Muskingum-Cunge (MC) and the revised, mass-conservative Muskingum-Cunge-Todini (MCT) approach, whereby geometrical cross sections are treated analytically in both cases. We initially compare the three SV solvers for a straight mild-sloping prismatic channel with geometric cross sections and a synthetic hydrograph as boundary conditions against the analytical MC and MCT solutions. The comparison is substantiated by the fact that in this flow regime the conditions for the parabolic equation model solved by MC and MCT are met. Through this intercomparison we show that all approaches have comparable mass and momentum conservation properties, except the MC. Then we extend the MCT to use natural cross sections for a real irregular river channel forced by an observed triple-peak event and compare the results with SOBEK. The model intercomparison demonstrates that the VPM in the form of MCT can be a computationally efficient, fully mass and momentum conservative approach and therefore constitutes a valid alternative to Saint-Venant based flood wave routing for a wide variety of rivers and channels in the world when downstream boundary conditions or hydraulic structures are non-influential.
Qualitative simulation of bathymetric changes due to reservoir sedimentation: A Japanese case study

PubMed Central

Dai, Wenhong; Larson, Magnus; Beebo, Qaid Naamo; Xie, Qiancheng

2017-01-01

Sediment-dynamics modeling is a useful tool for estimating a dam’s lifespan and its cost–benefit analysis. Collecting real data for sediment-dynamics analysis from conventional field survey methods is both tedious and expensive. Therefore, for most rivers, the historical record of data is either missing or not very detailed. Available data and existing tools have much potential and may be used for qualitative prediction of future bathymetric change trend. This study shows that proxy approaches may be used to increase the spatiotemporal resolution of flow data, and hypothesize the river cross-sections and sediment data. Sediment-dynamics analysis of the reach of the Tenryu River upstream of Sakuma Dam in Japan was performed to predict its future bathymetric changes using a 1D numerical model (HEC-RAS). In this case study, only annually-averaged flow data and the river’s longitudinal bed profile at 5-year intervals were available. Therefore, the other required data, including river cross-section and geometry and sediment inflow grain sizes, had to be hypothesized or assimilated indirectly. The model yielded a good qualitative agreement, with an R2 (coefficient of determination) of 0.8 for the observed and simulated bed profiles. A predictive simulation demonstrated that the useful life of the dam would end after the year 2035 (±5 years), which is in conformity with initial detailed estimates. The study indicates that a sediment-dynamic analysis can be performed even with a limited amount of data. However, such studies may only assess the qualitative trends of sediment dynamics. PMID:28384361
Rainwater content estimated using polarimetric radar parameters in the Heihe River Basin

NASA Astrophysics Data System (ADS)

Zhao, Guo; Chu, Rongzhong; Zhang, Tong; Jia, Wei

2013-02-01

The rainwater content of cold and arid regions has strong spatial and temporal heterogeneity. Representing rainwater content at high resolution can help us understand the characteristics of inland river basin water cycles and improve the prediction accuracy of hydrological models. Data were used from the Watershed Allied Telemetry Experimental Research (WATER) project of the Heihe River Basin, which is the second largest inland river basin in the arid regions of northwest China. We used raindrop size distributions to improve the rain water content estimation of meteorological radar and to obtain accurate rain water content data in this area. Subsequently, four estimation methods applied in the polarimetric radar were tested. The results of a non-linear regression method show that M(KDP, ZH, ZDR) has the highest accuracy for measuring rain water content. Finally, the formula for measuring the spatial rain water content was applied to a polarimetric radar with an X-band (714XDP). The influence of raindrop size distribution (DSD) on the formula M(KDP, ZH, ZDR) is lowest sensitivity, and it can be explained as follows. On the one hand, the horizontal and vertical front reflection cross sections of the radar are different, so KDP is proportional to the 3rd power of the raindrop diameter. On the other hand, the rear cross section of the radar is proportional to the sixth power of the raindrop diameter. The rainfall's spatial water content M is proportional to the 3rd power of the raindrop diameter, so the influence of the drop size distribution (DSD) on KDP is much smaller than that of ZH.
Prerequisites for Accurate Monitoring of River Discharge Based on Fixed-Location Velocity Measurements

NASA Astrophysics Data System (ADS)

Kästner, K.; Hoitink, A. J. F.; Torfs, P. J. J. F.; Vermeulen, B.; Ningsih, N. S.; Pramulya, M.

2018-02-01

River discharge has to be monitored reliably for effective water management. As river discharge cannot be measured directly, it is usually inferred from the water level. This practice is unreliable at places where the relation between water level and flow velocity is ambiguous. In such a case, the continuous measurement of the flow velocity can improve the discharge prediction. The emergence of horizontal acoustic Doppler current profilers (HADCPs) has made it possible to continuously measure the flow velocity. However, the profiling range of HADCPs is limited, so that a single instrument can only partially cover a wide cross section. The total discharge still has to be determined with a model. While the limitations of rating curves are well understood, there is not yet a comprehensive theory to assess the accuracy of discharge predicted from velocity measurements. Such a theory is necessary to discriminate which factors influence the measurements, and to improve instrument deployment as well as discharge prediction. This paper presents a generic method to assess the uncertainty of discharge predicted from range-limited velocity profiles. The theory shows that a major source of error is the variation of the ratio between the local and cross-section-averaged velocity. This variation is large near the banks, where HADCPs are usually deployed and can limit the advantage gained from the velocity measurement. We apply our theory at two gauging stations situated in the Kapuas River, Indonesia. We find that at one of the two stations the index velocity does not outperform a simple rating curve.
Measuring stream discharge by non-contact methods: A proof-of-concept experiment

USGS Publications Warehouse

Costa, J.E.; Spicer, K.R.; Cheng, R.T.; Haeni, F.P.; Melcher, N.B.; Thurman, E.M.; Plant, W.J.; Keller, W.C.

2000-01-01

This report describes an experiment to make a completely non-contact open-channel discharge measurement. A van-mounted, pulsed doppler (10GHz) radar collected surface-velocity data across the 183-m wide Skagit River, Washington at a USGS streamgaging station using Bragg scattering from short waves produced by turbulent boils on the surface of the river. Surface velocities were converted to mean velocities for 25 sub-sections by assuming a normal open-channel velocity profile (surface velocity times 0.85). Channel cross-sectional area was measured using a 100 MHz ground-penetrating radar antenna suspended from a cableway car over the river. Seven acoustic doppler current profiler discharge measurements and a conventional current-meter discharge measurement were also made. Three non-contact discharge measurements completed in about a 1-hour period were within 1 % of the gaging station rating curve discharge values. With further refinements, it is thought that open-channel flow can be measured reliably by non-contact methods.
Modeling flash floods in southern France for road management purposes

NASA Astrophysics Data System (ADS)

Vincendon, Béatrice; Édouard, Simon; Dewaele, Hélène; Ducrocq, Véronique; Lespinas, Franck; Delrieu, Guy; Anquetin, Sandrine

2016-10-01

Flash-floods are among the most devastating hazards in the Mediterranean. A major subset of damage and casualties caused by flooding is related to road submersion. Distributed hydrological nowcasting can be used for road flooding monitoring. This requires rainfall-runoff simulations at a high space and time resolution. Distributed hydrological models, such as the ISBA-TOP coupled system used in this study, are designed to simulate discharges for any cross-section of a river but they are generally calibrated for certain outlets and give deteriorated results for the sub-catchment outlets. The paper first analyses ISBA-TOP discharge simulations in the French Mediterranean region for target points different from the outlets used for calibration. The sensitivity of the model to its governing factors is examined to highlight the validity of results obtained for ungauged river sections compared with those obtained for the main gauged outlets. The use of improved model inputs is found beneficial for sub-catchments simulation. The calibration procedure however provides the parameters' values for the main outlets only and these choices influence the simulations for ungauged catchments or sub-catchments. As a result, a new version of ISBA-TOP system without any parameter to calibrate is used to produce diagnostics relevant for quantifying the risk of road submersion. A first diagnostic is the simulated runoff spatial distribution, it provides a useful information about areas with a high risk of submersion. Then an indicator of the flood severity is given by simulated discharges presented with respect to return periods. The latter has to be used together with information about the vulnerability of road-river cross-sections.

Computation of discharge using the index-velocity method in tidally affected areas

USGS Publications Warehouse

Ruhl, Catherine A.; Simpson, Michael R.

2005-01-01

Computation of a discharge time-series in a tidally affected area is a two-step process. First, the cross-sectional area is computed on the basis of measured water levels and the mean cross-sectional velocity is computed on the basis of the measured index velocity. Then discharge is calculated as the product of the area and mean velocity. Daily mean discharge is computed as the daily average of the low-pass filtered discharge. The Sacramento-San Joaquin River Delta and San Francisco Bay, California, is an area that is strongly influenced by the tides, and therefore is used as an example of how this methodology is used.
Plans, Trains, and Automobiles: Big River Crossing Issues in a Small Community

DOT National Transportation Integrated Search

1999-01-01

This paper addresses cross-cutting topics associated with the replacement of a : regional Mississippi River crossing along the Great River Road. The breadth and : depth of issues define the ease with which transportation problems can be solved. : In ...
Data collected to support monitoring of constructed emergent sandbar habitat on the Missouri River downstream from Gavins Point Dam, South Dakota and Nebraska, 2004-06

USGS Publications Warehouse

Thompson, Ryan F.; Johnson, Michaela R.; Andersen, Michael J.

2007-01-01

The U.S. Army Corps of Engineers has constructed emergent sandbar habitat on sections of the Missouri River bordering South Dakota and Nebraska downstream from Gavins Point Dam to create and enhance habitat for threatened and endangered bird species. Two areas near river miles 761.3 and 769.8 were selected for construction of emergent sandbar habitat. Pre- and postconstruction data were collected by the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, to evaluate the success of the habitat management techniques. Data collected include pre- and postconstruction channel-geometry data (bathymetric and topographic) for areas upstream from, downstream from, and within each construction site. Water-velocity data were collected for selected parts of the site near river mile 769.8. Instruments and methods used in data collection, as well as quality-assurance and quality-control measures, are described. Geospatial channel-geometry data are presented for transects of the river channel as cross sections and as geographical information system shapefiles. Geospatial land-surface elevation data are provided for part of each site in the form of a color-shaded relief map. Geospatial water-velocity data also are provided as color-shaded maps and geographical information system shapefiles.
Italian river crossing; Horizontal drilling meets pipeline project criteria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1988-06-01

The River Piave flows out of the Italian Alps, crossing the Veneto farmlands on its way to the Adriatic Sea. It is an important commerce-carrying waterway. SNAM, the Italian state gas pipeline company, wanted to install a 22-in. pipeline across the Piave just north of Venice. The method chosen for crossing the river had to meet several important criteria. InArc had used its river crossing method on seven previous SNAM projects and recommended the Piave crossing should be drilled. This paper describes the use of this horizontal drilling method for this application.
Rock Erodibility as a Dynamic Variable Driven by the Interplay between Erosion and Weathering in Bedrock Channels: Examples from Great Falls, Virginia, USA

NASA Astrophysics Data System (ADS)

Hancock, G. S.; Huettenmoser, J.; Shobe, C. M.; Eppes, M. C.

2016-12-01

Rock erodibility in channels is a primary control on the stresses required to erode bedrock (e.g., Sklar and Dietrich, 2001). Erodibility tends to be treated as a uniform and fixed variable at the scale of channel cross-sections, particularly in models of channel profile evolution. Here we present field data supporting the hypothesis (Hancock et al., 2011) that erodibility is a dynamic variable, driven by the interplay between erosion rate and weathering processes within cross-sections. We hypothesize that rock weathering varies in cross-sections from virtually unweathered in the thalweg, where frequent stripping removes weathered rock, to a degree of weathering determined by the frequency of erosive events higher on the channel margin. We test this hypothesis on three tributaries to the Potomac River underlain by similar bedrock but with varying erosion rates ( 0.01 to 0.8 m/ky). At multiple heights within three cross-sections on three tributaries, we measured compressive strength with a Schmidt hammer, surface roughness with a contour gage, and density and length of visible cracks. Compressive strength decreased with height in all nine cross-sections by 10% to 50%, and surface roughness increased with height in seven cross-sections by 25% - 45%, with the remaining two showing minimal change. Crack density increased with height in the three cross-sections measured. Taken together these data demonstrate increases in weathering intensity, and presumably, rock erodibility, with height. The y-intercept of the relation between height and the three measured variables were nearly identical, suggesting that thalweg erodibility was similar on each channel, as predicted, even though erodibility higher in the cross-section were markedly different. The rate at which the three variables changed with height in each cross-section is strongly related to stream power. Assuming stream power is a reasonable surrogate for erosion rate, this result implies that erosion rate can be a primary influence on the distribution of erodibility within channel cross-sections. We conclude that the interplay between rates of erosion and weathering produces spatial as well as temporal variability in erodibility which, in turn, influences channel form and gradient.
Variability of pesticide exposure in a stream mesocosm system: macrophyte-dominated vs. non-vegetated sections.

PubMed

Beketov, Mikhail A; Liess, Matthias

2008-12-01

For flowing water bodies no information is available about patterns of contaminant distribution in flowing water compared to macrophyte-dominated structures. The aim of the study was to examine temporal dynamic and spatial cross-channel variability of pulse exposure of the insecticide thiacloprid in outdoor stream mesocosms. Two distinct cross-channel sections have been considered: macrophyte-dominated littoral and non-vegetated midstream. Median disappearance time ranged from 17 to 43 h (water phase, midstream). We showed that during the exposure pulse (10h) thiacloprid concentrations in the macrophyte-dominated section were 20-60% lower than those in the non-vegetated section. This suggests that spatial variability in contaminant concentrations, particularly in streams containing macrophytes, should be taken into account to enable a more realistic assessment of (i) exposure and associated effects and (ii) mass transport of pesticides and other chemicals into river systems (e.g. losses with surface runoff).
Electrical resistivity investigation of fluvial geomorphology to evaluate potential seepage conduits to agricultural lands along the San Joaquin River, Merced County, California, 2012–13

USGS Publications Warehouse

Groover, Krishangi D.; Burgess, Matthew K.; Howle, James F.; Phillips, Steven P.

2017-02-08

Increased flows in the San Joaquin River, part of the San Joaquin River Restoration Program, are designed to help restore fish populations. However, increased seepage losses could result from these higher restoration flows, which could exacerbate existing drainage problems in neighboring agricultural lands and potentially damage crops. Channel deposits of abandoned river meanders that are hydraulically connected to the river could act as seepage conduits, allowing rapid and widespread water-table rise during restoration flows. There is a need to identify the geometry and properties of these channel deposits to assess their role in potential increased seepage effects and to evaluate management alternatives for reducing seepage. Electrical and electromagnetic surface geophysical methods have provided a reliable proxy for lithology in studies of fluvial and hyporheic systems where a sufficient electrical contrast exists between deposits of differing grain size. In this study, direct-current (DC) resistivity was used to measure subsurface resistivity to identify channel deposits and to map their subsurface geometry. The efficacy of this method was assessed by using DC resistivity surveys collected along a reach of the San Joaquin River in Merced County, California, during the summers of 2012 and 2013, in conjunction with borings and associated measurements from a hydraulic profiling tool. Modeled DC resistivity data corresponded with data from cores, hand-auger samples, a hydraulic profiling tool, and aerial photographs, confirming that DC resistivity is effective for differentiating between silt and sand deposits in this setting. Modeled DC resistivity data provided detailed two-dimensional cross-sectional resistivity profiles to a depth of about 20 meters. The distribution of high-resistivity units in these profiles was used as a proxy for identifying areas of high hydraulic conductivity. These data were used subsequently to guide the location and depth of wells installed onsite for monitoring flow in the channel deposits. Estimates of the cross-sectional area of channel deposits from DC resistivity pseudosections can provide critical input for groundwater-flow models designed to simulate river seepage and evaluate seepage-management alternatives.
Modelling of hyperconcentrated flood and channel evolution in a braided reach using a dynamically coupled one-dimensional approach

NASA Astrophysics Data System (ADS)

Xia, Junqiang; Zhang, Xiaolei; Wang, Zenghui; Li, Jie; Zhou, Meirong

2018-06-01

Hyperconcentrated sediment-laden floods often occur in a braided reach of the Lower Yellow River, usually leading to significant channel evolution. A one-dimensional (1D) morphodynamic model using a dynamically coupled solution approach is developed to simulate hyperconcentrated flood and channel evolution in the braided reach with an extremely irregular cross-sectional geometry. In the model, the improved equations for hydrodynamics account for the effects of sediment concentration and bed evolution, which are coupled with the equations of non-equilibrium sediment transport and bed evolution. The model was validated using measurements from the 1977 and 2004 hyperconcentrated floods. Furthermore, the effects were investigated of different cross-sectional spacings and allocation modes of channel deformation area on the model results. It was found that a suitable cross-sectional distance of less than 3 km should be adopted when simulating hyperconcentrated floods, and the results using the uniform allocation mode can agree better with measurements than other two allocation modes.
A Structural Analysis of the Lewiston Basin, Clarkston, WA

NASA Astrophysics Data System (ADS)

Alloway, M.; Watkinson, A.; Reidel, S. P.

2010-12-01

The Lewiston Structure is located in southeastern Washington / west-central Idaho and is a generally E-W trending asymmetric, non-cylindrical anticline in the Columbia River Basalt Group (CRBG) that transfers displacement into the Limekiln fault system to the southeast. A serial cross-section analysis and 3-D construction of this structure shows how the fold varies along its trend and sheds light on the deformational history of the Lewiston Basin. Construction of the fold’s 3-D form shows that the fold’s wavelength increases and amplitude decreases eastward along its trend. Balanced cross-sections show approximately 5% shortening across the structure which is consistent with the Yakima Fold Belt (YFB). Although the structure is similar to the YFB, it does not form part of a belt and its local nature has been suggested to mark the cratonic boundary of the Cretaceous. Discovery of an angular unconformity in the Grande Ronde Basalt - reverse polarity unit 1 (GRB-R1) proves that the NE trending section of the fold was deforming during emplacement of R1 and allows separation of the fold into two structural domains. Analysis of the two domains using the Gauss method for heterogeneous fault-slip data indicate NW-SE shortening during R1 time and N-S shortening for post CRBG emplacement. Furthermore, slip data for strain-inversion and specification of spatial-distribution patterns help identify the existence of a transpressional tectonic environment. The nature of faulting associated with the Lewiston Structure is a topic of some debate, namely the presence of a reverse fault on the southern limb of the fold conspicuously hidden by the Snake River. The reverse fault under debate outcrops to the east of the field area and is GRB-R2 (reverse polarity unit 2) thrust over Pliocene gravels. Better control on unit thicknesses and map contacts rule out the possibility of a reverse fault exposed on the surface of the southern limb of the fold in the field area. This major fault dies out or becomes blind before reaching the ID-WA border and the conspicuous change in attitude from the north side of the river to the south is accommodated by an abrupt fold hinge beneath the river. Three-dimensional representation of how the structure varies along its trend, not to scale. A-A' crosses the location where the Snake River changes direction from E-W to S-N. G-G' was modified from Garwood and Bush (2005) and is outside of the field area.
On the effects of improved cross-section representation in one dimensional flow routing models applied to ephemeral rivers

USDA-ARS?s Scientific Manuscript database

Flash floods are an important component of the semi-arid hydrological cycle, and provide the potential for groundwater recharge as well as posing a dangerous natural hazard. A number of catchment models have been applied to flash flood prediction; however, in general they perform poorly. This study ...
6. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL PIER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW OF THE EASTERN BRIDGE ELEVATION, SHOWING CENTRAL PIER AND ASSOCIATED SUPERSTRUCTURE, AND CANTILEVERED NORTHERN TRUSS SECTION. NOTE THE JOIN BETWEEN EYE-BAR (LEFT) AND RIVETED CHANNEL (RIGHT) LOWER BRIDGE CHORDS AT CENTER LEFT OF PHOTOGRAPH. FACING NORTH. - Coverts Crossing Bridge, Spanning Mahoning River along Township Route 372 (Covert Road), New Castle, Lawrence County, PA
The subsurface cross section resistivity using magnetotelluric method in Pelabuhan Ratu area, West Java, implication for geological hazard mitigation

NASA Astrophysics Data System (ADS)

Gaffar, Eddy Z.

2016-02-01

Pelabuhan Ratu area is located on the south coast of West Java. Pelabuhan Ratu area's rapid development and population growth were partly stimulated by the Indonesian Government Regulation No. 66 the year 1998 that made Pelabuhan Ratu the capital city of the district of Sukabumi. Because of this fact, it is very important to create a geological hazard mitigation plan for the area. Pelabuhan Ratu were passed by two major faults: Cimandiri fault in the western and Citarik fault in the eastern. Cimandiri fault starts from the upstream of Cimandiri River to the southern of Sukabumi and Cianjur city. While Citarik fault starts from the Citarik River until the Salak Mountain. These two faults needs to be observed closely as they are prone to cause earthquake in the area. To mitigate earthquake that is estimated will occur at Cimandiri fault or the Citarik fault, the Research Center for Geotechnology LIPI conducted research using Magnetotelluric (MT) method with artificial Phoenix MT tool to determine the cross-section resistivity of the Pelabuhan Ratu and the surrounding area. Measurements were taken at 40 points along the highway towards Jampang to Pelabuhan Ratu, and to Bandung towards Cibadak with a distance of less than 500 meters between the measuring points. Measurement results using this tool will generate AMT cross-section resistivity to a depth of 1500 meters below the surface. Cross-section resistivity measurement results showed that there was a layer of rock with about 10 Ohm-m to 1000 Ohm-m resistivity. Rocks with resistivity of 10 Ohm-m was interpreted as conductive rocks that were loose or sandstone containing water. If an earthquake to occur in this area, it will lead to a strong movement and liquefaction that will destroy buildings and potentially cause casualties in this area.
Assimilation of measurement data in hydrodynamic modeling

NASA Astrophysics Data System (ADS)

Karamuz, Emilia; Romanowicz, Renata J.

2016-04-01

This study focuses on developing methods to combine ground-based data from operational monitoring with data from satellite imaging to obtain a more accurate evaluation of flood inundation extents. The distributed flow model MIKE 11 was used to determine the flooding areas for a flood event with available satellite data. Model conditioning was based on the integrated use of data from remote measurement techniques and traditional data from gauging stations. Such conditioning of the model improves the quality of fit of the model results. The use of high resolution satellite images (from IKONOS, QuickBird e.t.c) and LiDAR Digital Elevation Model (DEM) allows information on water levels to be extended to practically any chosen cross-section of the tested section of the river. This approach allows for a better assessment of inundation extent, particularly in areas with a scarce network of gauging stations. We apply approximate Bayesian analysis to integrate the information on flood extent originating from different sources. The approach described above was applied to the Middle River Vistula reach, from the Zawichost to Warsaw gauging stations. For this part of the river the detailed geometry of the river bed and floodplain data were available. Finally, three selected sub-sections were analyzed with the most suitable satellite images of inundation area. ACKNOWLEDGEMENTS This research was supported by the Institute of Geophysics Polish Academy of Sciences through the Young Scientist Grant no. 3b/IGF PAN/2015.
Salinity of the Delaware Estuary

USGS Publications Warehouse

Cohen, Bernard; McCarthy, Leo T.

1962-01-01

The purpose of this investigation was to obtain data on and study the factors affecting the salinity of the Delaware River from Philadelphia, Pa., to the Appoquinimink River, Del. The general chemical quality of water in the estuary is described, including changes in salinity in the river cross section and profile, diurnal and seasonal changes, and the effects of rainfall, sea level, and winds on salinity. Relationships are established of the concentrations of chloride and dissolved solids to specific conductance. In addition to chloride profiles and isochlor plots, time series are plotted for salinity or some quantity representing salinity, fresh-water discharge, mean river level, and mean sea level. The two major variables which appear to have the greatest effect on the salinity of the estuary are the fresh-water flow of the river and sea level. The most favorable combination of these variables for salt-water encroachment occurs from August to early October and the least favorable combination occurs between December and May.
A flow-simulation model of the tidal Potomac River

USGS Publications Warehouse

Schaffranek, Raymond W.

1987-01-01

A one-dimensional model capable of simulating flow in a network of interconnected channels has been applied to the tidal Potomac River including its major tributaries and embayments between Washington, D.C., and Indian Head, Md. The model can be used to compute water-surface elevations and flow discharges at any of 66 predetermined locations or at any alternative river cross sections definable within the network of channels. In addition, the model can be used to provide tidal-interchange flow volumes and to evaluate tidal excursions and the flushing properties of the riverine system. Comparisons of model-computed results with measured watersurface elevations and discharges demonstrate the validity and accuracy of the model. Tidal-cycle flow volumes computed by the calibrated model have been verified to be within an accuracy of ? 10 percent. Quantitative characteristics of the hydrodynamics of the tidal river are identified and discussed. The comprehensive flow data provided by the model can be used to better understand the geochemical, biological, and other processes affecting the river's water quality.
Investigation of Hyporheic Thermal Flux and Downstream Attenuation Driven by Hydropeaking in the Colorado River, Austin, Texas

NASA Astrophysics Data System (ADS)

Watson, J. A.; Cardenas, M. B.; Neilson, B. T.; Bennett, P. C.

2015-12-01

Thermal flux related to regulated river hydropeaking has been extensively researched at the single-study site scale, but little work has been done quantifying the downstream attenuation of a single regulated flood pulse at multiple sites. In order to better understand this flood pulse attenuation we instrumented four sites with temperature probes along a 91 km stretch of the Colorado River downstream of longhorn dam, Austin, TX. Piezometer transects perpendicular to the river at each site were instrumented with HOBO thermistors over a 1.4m screened interval within the saturated zone at 20cm spacing. As flood pulses are attenuated downstream, temperature gradients and distance of lateral temperature pulse penetration into the bank are hypothesized to decrease. The data collected in this investigation will test this hypothesis by providing 2D temperature cross-sections along an attenuating flood pulse, providing detailed spatial data on temperature gradients adjacent to the river.
Testing laser-based sensors for continuous in situ monitoring of suspended sediment in the Colorado River, Arizona

USGS Publications Warehouse

Melis, T.S.; Topping, D.J.; Rubin, D.M.; Bogen, J.; Fergus, T.; Walling, D.

2003-01-01

High-resolution monitoring of sand mass balance in the Colorado River below Glen Canyon Dam, Arizona, USA, is needed for environmental management. In the Grand Canyon, frequent collection of suspended-sediment samples from cableways is logistically complicated, costly and provides limited spatial and temporal resolution. In situ laser sensors were tested in the Colorado River as an alternative method for monitoring the river's suspended transport. LISST data were collected at a fixed-depth, near-shore site while isokinetic measurements were simultaneously made from a nearby cableway. Diurnal variations in LISST grain size and concentration data compared well with depth-integrated, cross-section data. Tbe LISST was also successfully used to electronically trigger an ISCO 6712 pump sampler to provide continuous monitoring during periods when suspended concentrations exceeded the LISST's measurement range. Initial results indicate that the LISST can provide useful high-resolution suspended-sediment data within the Colorado River, when optics are maintained on a weekly basis.
River bathymetry estimation based on the floodplains topography.

NASA Astrophysics Data System (ADS)

Bureš, Luděk; Máca, Petr; Roub, Radek; Pech, Pavel; Hejduk, Tomáš; Novák, Pavel

2017-04-01

Topographic model including River bathymetry (bed topography) is required for hydrodynamic simulation, water quality modelling, flood inundation mapping, sediment transport, ecological and geomorphologic assessments. The most common way to create the river bathymetry is to use of the spatial interpolation of discrete points or cross sections data. The quality of the generated bathymetry is dependent on the quality of the measurements, on the used technology and on the size of input dataset. Extensive measurements are often time consuming and expensive. Other option for creating of the river bathymetry is to use the methods of mathematical modelling. In the presented contribution we created the river bathymetry model. Model is based on the analytical curves. The curves are bent into shape of the cross sections. For the best description of the river bathymetry we need to know the values of the model parameters. For finding these parameters we use of the global optimization methods. The global optimization schemes is based on heuristics inspired by the natural processes. We use new type of DE (differential evolution) for finding the solutions of inverse problems, related to the parameters of mathematical model of river bed surfaces. The presented analysis discuss the dependence of model parameters on the selected characteristics. Selected characteristics are: (1) Topographic characteristics (slope and curvature in the left and right floodplains) determined on the base of DTM 5G (digital terrain model). (2) Optimization scheme. (3) Type of used analytical curves. The novel approach is applied on the three parts of Vltava river in Czech Republic. Each part of the river is described on the base of the point field. The point fields was measured with ADCP probe River surveyor M9. This work was supported by the Technology Agency of the Czech Republic, programme Alpha (project TA04020042 - New technologies bathymetry of rivers and reservoirs to determine their storage capacity and monitor the amount and dynamics of sediments) and Internal Grant Agency of Faculty of Environmental Sciences (CULS) (IGA/20164233). Keywords: bathymetry, global optimization, bed topography References: Merwade, Venkatesh. "Effect of spatial trends on interpolation of river bathymetry." Journal of Hydrology, 371.1, 169-181, 2009. Legleiter, Carl J., and Phaedon C. Kyriakidis. Spatial prediction of river channel topography by kriging. Earth Surface Processes and Landforms, 33.6 , 841-867, 2008. P. Maca and P. Pech and and J. Pavlasek. Comparing the Selected Transfer Functions and Local Optimization Methods for Neural Network Flood Runoff Forecast. Mathematical Problems in Engineering, vol. 2014, Article ID 782351, 10 pages, 2014. M. Jakubcova and P. Maca and and P. Pech. A Comparison of Selected Modifications of the Particle Swarm Optimization Algorithm. Journal of Applied Mathematics, vol. 2014, Article ID 293087, 10 pages, 2014.
Understanding whose births get registered: a cross sectional study in Bauchi and Cross River states, Nigeria.

PubMed

Adi, Atam E; Abdu, Tukur; Khan, Amir; Rashid, Musa Haruna; Ebri, Ubi E; Cockcroft, Anne; Andersson, Neil

2015-03-13

It is a recognized child right to acquire a name and a nationality, and birth registration may be necessary to allow access to services, but the level of birth registration is low in Nigeria. A household survey about management of childhood illnesses provided an opportunity to examine actionable determinants of birth registration of children in Bauchi and Cross River states of Nigeria. Trained field teams visited households in a stratified random cluster sample of 90 enumeration areas in each state. They administered a questionnaire to women 14-49 years old which included questions about birth registration of their children 0-47 months old and about socio-economic and other factors potentially related to birth registration, including education of the parents, poverty (food sufficiency), marital status of the mother, maternal antenatal care and place of delivery of the last pregnancy. Bivariate then multivariate analysis examined associations with birth registration. Facilitators later conducted separate male and female focus group discussions in the same 90 communities in each state, discussing the reasons for the findings about levels of birth registration. Nearly half (45%) of 8602 children in Cross River State and only a fifth (19%) of 9837 in Bauchi State had birth certificates (seen or unseen). In both states, children whose mothers attended antenatal care and who delivered in a government health facility in their last pregnancy were more likely to have a birth certificate, as were children of more educated parents, from less poor households, and from urban communities. Focus group discussions revealed that many people did not know about birth certificates or where to get them, and parents were discouraged from getting birth certificates because of the unofficial payments involved. There are low levels of birth registration in Bauchi and Cross River states, particularly among disadvantaged households. As a result of this study, both states have planned interventions to increase birth registration, including closer collaboration between the National Population Commissions and state health services.
Combining split-beam and dual-frequency identification sonars to estimate abundance of anadromous fishes in the Roanoke River, North Carolina

USGS Publications Warehouse

Hughes, Jacob B.; Hightower, Joseph E.

2015-01-01

Riverine hydroacoustic techniques are an effective method for evaluating abundance of upstream migrating anadromous fishes. To use these methods in the Roanoke River, North Carolina, at a wide site with uneven bottom topography, we used a combination of split-beam sonar and dual-frequency identification sonar (DIDSON) deployments. We aimed a split-beam sonar horizontally to monitor midchannel and near-bottom zones continuously over the 3-month spring monitoring periods in 2010 and 2011. The DIDSON was rotated between seven cross-channel locations (using a vertical aim) and nearshore regions (using horizontal aims). Vertical deployment addressed blind spots in split-beam coverage along the bottom and provided reliable information about the cross-channel and vertical distributions of upstream migrants. Using a Bayesian framework, we modeled sonar counts within four cross-channel strata and apportioned counts by species using species proportions from boat electrofishing and gill netting. Modeled estimates (95% credible intervals [CIs]) of total upstream migrants in 2010 and 2011 were 2.5 million (95% CI, 2.4–2.6 million) and 3.6 million (95% CI, 3.4–3.9 million), respectively. Results indicated that upstream migrants are extremely shore- and bottom-oriented, suggesting nearshore DIDSON monitoring improved the accuracy and precision of our estimates. This monitoring protocol and model may be widely applicable to river systems regardless of their cross-sectional width or profile.

Sediment transport monitoring for sustainable hydropower development

NASA Astrophysics Data System (ADS)

Rüther, Nils; Guerrero, Massimo; Stokseth, Siri

2015-04-01

Due to the increasing demand of CO2 neutral energy not only in Europe but also in World, a relatively large amount of new hydro power plants (HPP) are built. In addition, will existing ones refurbished and renewed in order to run them more cost effective. A huge thread to HPPs is incoming sediments in suspension from the rivers upstream. The sediments settle in the reservoir and reduce the effective head and volume and reduce consequently the life time of the reservoir. In addition are the fine sediments causing severe damages to turbines and infrastructure of a HPP. For estimating the amount of incoming sediments in suspension and therefore planning efficient counter measures, it is essential to monitor the rivers within the catchment of the HPP for suspended sediments. This work is considerably time consuming and requires highly educated personnel and is therefore expensive. Consequently will this study present a method to measure suspended sediment concentrations and their grain size distribution with a dual frequency acoustic Doppler current profiler (ADCP). This method is more cost effective and reliable in comparison to traditional measurement methods. Having more detailed information about the sediments being transported in a river, the hydro power plant can be planned, built, and operated much more efficiently and sustainable. The two horizontal ADCPs are installed at a measurement cross section in the Devoll river in Albania. To verify the new method, the suspended load concentrations will be monitored also in the traditional ways at the same cross sections. It is planned to install turbidity measurement devices included with an automatic sampling devices. It is also planned to use an optical in situ measurement device (LISST SL by Sequoia Inc.) to have detailed information of sediment concentration and grain sizes over the depth.
Sediment-stabilizing and Destabilizing Ecoengineering Species from River to Estuary: the Case of the Scheldt System

NASA Astrophysics Data System (ADS)

Selakovic, S.; Cozzoli, F.; Leuven, J.; Van Braeckel, A.; Speybroeck, J.; Kleinhans, M. G.; Bouma, T.

2017-12-01

Interactions between organisms and landscape forming processes play an important role in evolution of coastal landscapes. In particular, biota has a strong potential to interact with important geomorphological processes such as sediment dynamics. Although many studies worked towards quantifying the impact of different species groups on sediment dynamics, information has been gathered on an ad hoc base. Depending on species' traits and distribution, functional groups of ecoengineering species may have differential effects on sediment deposition and erosion. We hypothesize that the spatial distributions of sediment-stabilizing and destabilizing species across the channel and along the whole salinity gradient of an estuary partly determine the planform shape and channel-shoal morphology of estuaries. To test this hypothesis, we analyze vegetation and macrobenthic data taking the Scheldt river-estuarine continuum as model ecosystem. We identify species traits with important effects on sediment dynamics and use them to form functional groups. By using linearized mixed modelling, we are able to accurately describe the distributions of the different functional groups. We observe a clear distinction of dominant ecosystem engineering functional groups and their potential effects on the sediment in the river-estuarine continuum. The first results of longitudinal cross section show the highest effects of stabilizing plant species in riverine and sediment bioturbators in weak polyhaline part of continuum. The distribution of functional groups in transverse cross sections shows dominant stabilizing effect in supratidal zone compared to dominant destabilizing effect in the lower intertidal zone. This analysis offers a new and more general conceptualization of distributions of sediment stabilizing and destabilizing functional groups and their potential impacts on sediment dynamics, shoal patterns, and planform shapes in river-estuarine continuum. We intend to test this in future modelling and experiments.
Male responsibility and maternal morbidity: a cross-sectional study in two Nigerian states.

PubMed

Andersson, Neil; Omer, Khalid; Caldwell, Dawn; Dambam, Mohammed Musa; Maikudi, Ahmed Yahya; Effiong, Bassey; Ikpi, Edet; Udofia, Etuk; Khan, Amir; Ansari, Umaira; Ansari, Noor; Hamel, Candyce

2011-12-21

Nigeria continues to have high rates of maternal morbidity and mortality. This is partly associated with lack of adequate obstetric care, partly with high risks in pregnancy, including heavy work. We examined actionable risk factors and underlying determinants at community level in Bauchi and Cross River States of Nigeria, including several related to male responsibility in pregnancy. In 2009, field teams visited a stratified (urban/rural) last stage random sample of 180 enumeration areas drawn from the most recent censuses in each of Bauchi and Cross River states. A structured questionnaire administered in face-to-face interviews with women aged 15-49 years documented education, income, recent birth history, knowledge and attitudes related to safe birth, and deliveries in the last three years. Closed questions covered female genital mutilation, intimate partner violence (IPV) in the last year, IPV during the last pregnancy, work during the last pregnancy, and support during pregnancy. The outcome was complications in pregnancy and delivery (eclampsia, sepsis, bleeding) among survivors of childbirth in the last three years. We adjusted bivariate and multivariate analysis for clustering. The most consistent and prominent of 28 candidate risk factors and underlying determinants for non-fatal maternal morbidity was intimate partner violence (IPV) during pregnancy (ORa 2.15, 95%CIca 1.43-3.24 in Bauchi and ORa 1.5, 95%CI 1.20-2.03 in Cross River). Other spouse-related factors in the multivariate model included not discussing pregnancy with the spouse and, independently, IPV in the last year. Shortage of food in the last week was a factor in both Bauchi (ORa 1.66, 95%CIca 1.22-2.26) and Cross River (ORa 1.32, 95%CIca 1.15-1.53). Female genital mutilation was a factor among less well to do Bauchi women (ORa 2.1, 95%CIca 1.39-3.17) and all Cross River women (ORa 1.23, 95%CIca 1.1-1.5). Enhancing clinical protocols and skills can only benefit women in Nigeria and elsewhere. But the violence women experience throughout their lives--genital mutilation, domestic violence, and steep power gradients--is accentuated through pregnancy and childbirth, when women are most vulnerable. IPV especially in pregnancy, women's fear of husbands or partners and not discussing pregnancy are all within men's capacity to change.
The roles of physical habitat in reproduction and survival of pallid sturgeon and shovelnose sturgeon in the Lower Missouri River, progress 2005–06: Chapter D in Factors affecting the reproduction, recruitment, habitat, and population dynamics of pallid sturgeon and shovelnose sturgeon in the Missouri River

USGS Publications Warehouse

Jacobson, Robert B.; Johnson, Harold E.; Reuter, Joanna M.; Elliott, Caroline M.

2007-01-01

This report documents progress on three related components of habitat assessments in the Lower Missouri River during 2005–06. The habitat-use component links this research directly to sturgeon ecology research described in other chapters. The habitat availability and habitat dynamics assessments provide physical context for the ecological research. Results from 2005 to 2006 indicate that the methods developed to assess habitat use, quality, quantity, and dynamics are appropriate and sufficiently accurate to address critical questions about sturgeon habitat on the Lower Missouri River. Preliminary analysis of habitats occupied by adult female shovelnose sturgeon indicates that migrating sturgeon do not select for depth but seem to select for lower than reach-averaged velocities and higher than reach-averaged velocity gradients. Data collected to compile, calibrate, and validate multidimensional hydraulic models in probable spawning reaches appear to be sufficient to support the modeling objectives. Monitoring of selected channel cross sections and long profiles multiple times during the year showed little change at the upstreammost reach over the range of flows measured during 2006, likely because of channel stability associated with an armored bed. Geomorphic changes documented at monitoring cross sections increased with distance downstream. Hydroacoustic substrate-class parameters documented systematic changes with discharge and with hydraulic environment across the channel. Similarly, bed velocity varied predictably with discharge and hydraulic environment, indicating its potential as an indicator of bedload sediment transport. Longitudinal profiles showed substantial downstream movement of dunes over the monitored discharges, as well as substantial within-year variability in dune size. Observations of geomorphic change during the moderate flow range of 2006 support the hypothesis that the magnitude of flow modifications under consideration on the Lower Missouri River will be sufficient to transport sediment and potentially modify spawning habitats.
Safety evaluation model of urban cross-river tunnel based on driving simulation.

PubMed

Ma, Yingqi; Lu, Linjun; Lu, Jian John

2017-09-01

Currently, Shanghai urban cross-river tunnels have three principal characteristics: increased traffic, a high accident rate and rapidly developing construction. Because of their complex geographic and hydrological characteristics, the alignment conditions in urban cross-river tunnels are more complicated than in highway tunnels, so a safety evaluation of urban cross-river tunnels is necessary to suggest follow-up construction and changes in operational management. A driving risk index (DRI) for urban cross-river tunnels was proposed in this study. An index system was also constructed, combining eight factors derived from the output of a driving simulator regarding three aspects of risk due to following, lateral accidents and driver workload. Analytic hierarchy process methods and expert marking and normalization processing were applied to construct a mathematical model for the DRI. The driving simulator was used to simulate 12 Shanghai urban cross-river tunnels and a relationship was obtained between the DRI for the tunnels and the corresponding accident rate (AR) via a regression analysis. The regression analysis results showed that the relationship between the DRI and the AR mapped to an exponential function with a high degree of fit. In the absence of detailed accident data, a safety evaluation model based on factors derived from a driving simulation can effectively assess the driving risk in urban cross-river tunnels constructed or in design.
Geomorphology of the lower Copper River, Alaska

USGS Publications Warehouse

Brabets, T.P.

1996-01-01

The Copper River, located in southcentral Alaska, drains an area of more than 24,000 square miles. About 30 miles above its mouth, this large river enters Miles Lake, a proglacial lake formed by the retreat of Miles Glacier. Downstream from the outlet of Miles Lake, the Copper River flows past the face of Childs Glacier before it enters a large, broad, alluvial flood plain. The Copper River Highway traverses this flood plain and in 1996, 11 bridges were located along this section of the highway. These bridges cross parts or all of the Copper River and in recent years, some of these bridges have sustained serious damage due to the changing course of the Copper River. Although the annual mean discharge of the lower Copper River is 57,400 cubic feet per second, most of the flow occurs during the summer months from snowmelt, rainfall, and glacial melt. Approximately every six years, an outburst flood from Van Cleve Lake, a glacier-dammed lake formed by Miles Glacier, releases approximately 1 million acre-feet of water into the Copper River. At the peak outflow rate from Van Cleve Lake, the flow of the Copper River will increase an additional 140,000 and 190,000 cubic feet per second. Bedload sampling and continuous seismic reflection were used to show that Miles Lake traps virtually all the bedload being transported by the Copper River as it enters the lake from the north. The reservoir-like effect of Miles Lake results in the armoring of the channel of the Copper River downstream from Miles Lakes, past Childs Glacier, until it reaches the alluvial flood plain. At this point, bedload transport begins again. The lower Copper River transports 69 million tons per year of suspended sediment, approximately the same quantity as the Yukon River, which drains an area of more than 300,000 square miles. By correlating concurrent flows from a long-term streamflow- gaging station on the Copper River with a short-term streamflow-gaging station at the outlet of Miles Lake, long-term flow characteristics of the lower Copper River were synthesized. Historical discharge and cross-section data indicate that as late as 1970, most of the flow of the lower Copper River was through the first three bridges of the Copper River Highway as it begins to traverse the alluvial flood plain. In the mid 1980's, a percentage of the flow had shifted away from these three bridges and in 1995, only 51 percent of the flow of the Copper River passed through them. Eight different years of aerial photography of the lower Copper River were analyzed using Geographical Information System techniques. This analysis indicated that no major channel changes were caused by the 1964 earthquake. A flood in 1981 that had a recurrence interval of more than 100 years caused significant channel changes in the lower Copper River. A probability analysis of the lower Copper River indicated stable areas and the long-term locations of channels. By knowing the number of times a particular area has been occupied by water and the last year an area was occupied by water, areas of instability can be located. A Markov analysis of the lower Copper River indicated that the tendency of the flood plain is to remain in its current state. Large floods of the magnitude of the 1981 event are believed to be the cause of major changes in the lower Copper River.
Geomorphology of the lower Copper River, Alaska

USGS Publications Warehouse

Brabets, Timothy P.

1997-01-01

The Copper River, located in southcentral Alaska, drains an area of more than 24,000 square miles. About 30 miles above its mouth, this large river enters Miles Lake, a proglacial lake formed by the retreat of Miles Glacier. Downstream from the outlet of Miles Lake, the Copper River flows past the face of Childs Glacier before it enters a large, broad, alluvial flood plain. The Copper River Highway traverses this flood plain and in 1995, 11 bridges were located along this section of the highway. These bridges cross parts of the Copper River and in recent years, some of these bridges have sustained serious damage due to the changing course of the Copper River. Although the annual mean discharge of the lower Copper River is 57,400 cubic feet per second, most of the flow occurs during the summer months from snowmelt, rainfall, and glacial melt. Approximately every six years, an outburst flood from Van Cleve Lake, a glacier-dammed lake formed by Miles Glacier, releases approximately 1 million acre-feet of water into the Copper River. When the outflow rate from Van Cleve Lake reaches it peak, the flow of the Copper River will increase between 150,000 to 190,000 cubic feet per second. Data collected by bedload sampling and continuous seismic reflection indicated that Miles Lake traps virtually all the bedload being transported by the Copper River as it enters the lake from the north. The reservoir-like effect of Miles Lake results in the armoring of the channel of the Copper River downstream from Miles Lake, past Childs Glacier, until it reaches the alluvial flood plain. At this point, bedload transport begins again. The lower Copper River transports 69 million tons per year of suspended sediment, approximately the same quantity as the Yukon River, which drains an area of more than 300,000 square miles. By correlating concurrent flows from a long-term streamflow-gaging station on the Copper River with a short-term streamflow-gaging station at the outlet of Miles Lake, long-term flow characteristics of the lower Copper River were synthesized. Historical discharge and cross-section data indicate that as late as 1970, most of the flow of the lower Copper River was through the first three bridges of the Copper River Highway as it begins to traverse the alluvial flood plain. In the mid 1980's, a percentage of the flow had shifted away from these three bridges and in 1995, only 51 percent of the flow of the Copper River passed through them. Eight different years of aerial photography of the lower Copper River were analyzed using Geographical Information System techniques. This analysis indicated that no major channel changes were caused by the 1964 earthquake. However, a flood in 1981 that had a recurrence interval of more than 100 years caused significant channel changes in the lower Copper River. A probability analysis of the lower Copper River indicated stable areas and the long-term locations of channels. By knowing the number of times a particular area has been occupied by water and the last year an area was occupied by water, areas of instability can be located. A Markov analysis of the lower Copper River indicated that the tendency of the flood plain is to remain in its current state. Large floods of the magnitude of the 1981 event are believed to be the cause of major changes in the lower Copper River.
Lecturers' Perception of Research Activities for Knowledge Production in Universities in Cross River State, Nigeria

ERIC Educational Resources Information Center

Uchendu, C. C.; Osim, R. O.; Odigwe, F. N.; Alade, F. N.

2014-01-01

This study examined lecturers' perception of research activities for knowledge production in universities in Cross River State, Nigeria. Two hypotheses were isolated to give direction to this investigation. 240 university lecturers were sampled from a population of 1,868 from the two universities in Cross River State, using stratified random…
Brown Trout removal effects on short-term survival and movement of Myxobolus cerebralis-resistant rainbow trout

USGS Publications Warehouse

Fetherman, Eric R.; Winkelman, Dana L.; Bailey, Larissa L.; Schisler, George J.; Davies, K.

2015-01-01

Following establishment of Myxobolus cerebralis (the parasite responsible for salmonid whirling disease) in Colorado, populations of Rainbow Trout Oncorhynchus mykissexperienced significant declines, whereas Brown Trout Salmo trutta densities increased in many locations across the state, potentially influencing the success of M. cerebralis-resistant Rainbow Trout reintroductions. We examined the effects of Brown Trout removal on the short-term (3-month) survival and movement of two crosses of reintroduced, M. cerebralis-resistant Rainbow Trout in the Cache la Poudre River, Colorado. Radio frequency identification passive integrated transponder tags and antennas were used to track movements of wild Brown Trout and stocked Rainbow Trout in reaches where Brown Trout had or had not been removed. Multistate mark–recapture models were used to estimate tagged fish apparent survival and movement in these sections 3 months following Brown Trout removal. A cross between the German Rainbow Trout and Colorado River Rainbow Trout strains exhibited similar survival and movement probabilities in the reaches, suggesting that the presence of Brown Trout did not affect its survival or movement. However, a cross between the German Rainbow Trout and Harrison Lake Rainbow Trout exhibited less movement from the reach in which Brown Trout had been removed. Despite this, the overall short-term benefits of the removal were equivocal, suggesting that Brown Trout removal may not be beneficial for the reintroduction of Rainbow Trout. Additionally, the logistical constraints of conducting removals in large river systems are substantial and may not be a viable management option in many rivers.
Large dams and alluvial rivers in the Anthropocene: The impacts of the Garrison and Oahe Dams on the Upper Missouri River

USGS Publications Warehouse

Skalak, Katherine; Benthem, Adam J.; Schenk, Edward R.; Hupp, Cliff R.; Galloway, Joel M.; Nustad, Rochelle A.; Wiche, Gregg J.

2013-01-01

The Missouri River has had a long history of anthropogenic modification with considerable impacts on river and riparian ecology, form, and function. During the 20th century, several large dam-building efforts in the basin served the needs for irrigation, flood control, navigation, and the generation of hydroelectric power. The managed flow provided a range of uses, including recreation, fisheries, and habitat. Fifteen dams impound the main stem of the river, with hundreds more on tributaries. Though the effects of dams and reservoirs are well-documented, their impacts have been studied individually, with relatively little attention paid to their interaction along a river corridor. We examine the morphological and sedimentological changes in the Upper Missouri River between the Garrison Dam in ND (operational in 1953) and Oahe Dam in SD (operational in 1959). Through historical aerial photography, stream gage data, and cross sectional surveys, we demonstrate that the influence of the upstream dam is still a major control of river dynamics when the backwater effects of the downstream reservoir begin. In the “Anthropocene”, dams are ubiquitous on large rivers and often occur in series, similar to the Garrison Dam Segment. We propose a conceptual model of how interacting dams might affect river geomorphology, resulting in distinct and recognizable morphologic sequences that we term “Inter-Dam sequence” characteristic of major rivers in the US.
Stream channel reference sites: An illustrated guide to field technique

Treesearch

Cheryl C Harrelson; C. L. Rawlins; John P. Potyondy

1994-01-01

This document is a guide to establishing permanent reference sites for gathering data about the physical characteristics of streams and rivers. The minimum procedure consists of the following: (1) select a site, (2) map the site and location, (3) measure the channel cross-section, (4) survey a longitudinal profile of the channel, (5) measure stream flow, (6) measure...
Bathymetric surveys of the Kootenai River near Bonners Ferry, Idaho, water year 2011

USGS Publications Warehouse

Fosness, Ryan L.

2013-01-01

In 2009, the Kootenai Tribe of Idaho released and implemented the Kootenai River Habitat Restoration Master Plan. This plan aimed to restore, enhance, and maintain the Kootenai River habitat and landscape to support and sustain habitat conditions for aquatic species and animal populations. In support of these restoration efforts, the U.S. Geological Survey, in cooperation with the Kootenai Tribe of Idaho, conducted high-resolution multibeam echosounder bathymetric surveys in May, June, and July 2011, as a baseline bathymetric monitoring survey on the Kootenai River near Bonners Ferry, Idaho. Three channel patterns or reaches exist in the study area—braided, meander, and a transitional zone connecting the braided and meander reaches. Bathymetric data were collected at three study areas in 2011 to provide: (1) surveys in unmapped portions of the meander reach; (2) monitoring of the presence and extent of sand along planned lines within a section of the meander reach; and (3) monitoring aggradation and degradation of the channel bed at specific cross sections within the braided reach and transitional zone. The bathymetric data will be used to update and verify flow models, calibrate and verify sediment transport modeling efforts, and aid in the biological assessment in support of the Kootenai River Habitat Restoration Master Plan. The data and planned lines for each study reach were produced in ASCII XYZ format supported by most geospatial software.
Lateral and vertical channel movement and potential for bed-material movement on the Madison River downstream from Earthquake Lake, Montana

USGS Publications Warehouse

Chase, Katherine J.; McCarthy, Peter M.

2012-01-01

The 1959 Hebgen Lake earthquake caused a massive landslide (Madison Slide) that dammed the Madison River and formed Earthquake Lake. The U.S. Army Corps of Engineers excavated a spillway through the Madison Slide to permit outflow from Earthquake Lake. In June 1970, high streamflows on the Madison River severely eroded the spillway channel and damaged the roadway embankment along U.S. Highway 287 downstream from the Madison Slide. Investigations undertaken following the 1970 flood events concluded that substantial erosion through and downstream from the spillway could be expected for streamflows greater than 3,500 cubic feet per second (ft3/s). Accordingly, the owners of Hebgen Dam, upstream from Earthquake Lake, have tried to manage releases from Hebgen Lake to prevent streamflows from exceeding 3,500 ft3/s measured at the U.S. Geological Survey (USGS) gaging station 0638800 Madison River at Kirby Ranch, near Cameron, Montana. Management of flow releases from Hebgen Lake to avoid exceeding the threshold streamflow at USGS gaging station 06038800 is difficult, and has been questioned for two reasons. First, no road damage was reported downstream from the Earthquake Lake outlet in 1993, 1996, and 1997 when streamflows exceeded the 3,500-ft3/s threshold. Second, the 3,500-ft3/s threshold generally precludes releases of higher flows that could be beneficial to the blue-ribbon trout fishery downstream in the Madison River. In response to concerns about minimizing streamflow downstream from Earthquake Lake and the possible armoring of the spillway, the USGS, in cooperation with the Madison River Fisheries Technical Advisory Committee (MADTAC; Bureau of Land Management; Montana Department of Environmental Quality; Montana Fish, Wildlife and Parks; PPL-Montana; U.S. Department of Agriculture Forest Service - Gallatin National Forest; and U.S. Fish and Wildlife Service), conducted a study to determine movement of the Madison River channel downstream from Earthquake Lake and to investigate the potential for bed material movement along the same reach. The purpose of this report is to present information about the lateral and vertical movement of the Madison River from 1970 to 2006 for a 1-mile reach downstream from Earthquake Lake and for Raynolds Pass Bridge, and to provide an analysis of the potential for bed-material movement so that MADTAC can evaluate the applicability of the previously determined threshold streamflow for initiation of damaging erosion. As part of this study channel cross sections originally surveyed by the USGS in 1971 were resurveyed in 2006. Incremental channel-movement distances were determined by comparing the stream centerlines from 14 aerial photographs taken between 1970 and 2006. Depths of channel incision and aggregation were determined by comparing the 2006 and 1971 cross-section and water-surface data. Particle sizes of bed and bank materials were measured in 2006 and 2008 using the pebble-count method and sieve analyses. A one-dimensional hydraulic-flow model (HEC-RAS) was used to calculate mean boundary-shear stresses for various streamflows; these calculated boundary-shear stresses were compared to calculated critical-shear stresses for the bed materials to determine the potential for bed-material movement. A comparison of lateral channel movement distances with annual peak streamflows shows that streamflows higher than the 3,500-ft3/s threshold were followed by lateral channel movement except from 1991 to 1992 and possibly from 1996 to 1997. However, it was not possible to discern whether the channel moved gradually or suddenly, or in response to one peak flow, to several peak flows, or to sustained flows. The channel moved between 2002 and 2005 even when streamflows were less than the threshold streamflow of 3,500 ft3/s. Comparisons of cross sections and aerial photographs show that the channel has moved laterally and incised and aggraded to varying degrees. The channel has developed meander bends and has incised as much as 5–12 feet (ft) through the upstream part of the Madison Slide (cross sections 1400–800). Near cross section 800, the stream has eroded into the steep right bank between the stream and the road where fill was mechanically placed after 1970. Channel movement also was noted downstream from the Madison Slide. Near Raynolds Pass Bridge, about 3 miles (mi) downstream from Earthquake Lake, elevations across the channel have changed by -1.4 ft to +1.9 ft, but these changes were local in nature and could represent a few rocks or depressions in the bed. Overall, it does not appear that the materials eroded from the Madison Slide are causing aggradation in the subreach near the Raynolds Pass Bridge. Comparisons of critical shear stresses to mean boundary-shear stresses indicate that the D50 particle sizes (median size) along the right side of the bed between cross sections 400 and 500 and along the right side of the bed between cross sections 1300 and 1400 could move at the threshold streamflow. In contrast, most of the D84 particle sizes at those two locations probably will not move at the threshold streamflow. This lack of movement for the larger particles at the threshold streamflow could lead to further armoring of the bed as the D50 and smaller-sized particles are removed from the bed and transported downstream. The Shields parameter values from 0.04 to 0.08 that were used to calculate critical shear stresses could be conservative for a high-gradient stream such as the Madison. A higher, less conservative, Shields parameter would result in higher critical shear stresses, meaning that higher streamflows would be required to move material than those reported herein. In addition, because materials in the channel thalweg are exposed to higher boundary-shear stresses than the materials along the sides of the channel, larger, more erosion-resistant materials likely exist in the deeper parts of the channel where high-flow depths and velocities prevented sediment sampling. Movement of these materials might require higher critical shear stresses than estimated in this report. Characterization of sediment sizes in the center of the stream and observation of bed-material movement for a range of streamflows could provide information to help refine the Shields parameter and critical-shear stress estimates for bed materials in the Madison River downstream from Earthquake Lake. Furthermore, resurveying cross sections and water-surface elevations more frequently (either annually or after high streamflows) could better define the relation between streamflow and lateral and vertical channel movement.
Hydraulic visibility and effective cross sections based on hydrodynamical modeling of flow lines gained by satellite altimetry

NASA Astrophysics Data System (ADS)

Biancamaria, S.; Garambois, P. A.; Calmant, S.; Roux, H.; Paris, A.; Monnier, J.; Santos da Silva, J.

2015-12-01

Hydrodynamic laws predict that irregularities in a river bed geometry produce spatial and temporal variations in the water level, hence in its slope. Conversely, observation of these changes is a goal of the SWOT mission with the determination of the discharge as a final objective. In this study, we analyse the relationship between river bed undulations and water surface for an ungauged reach of the Xingu river, a first order tributary of the Amazon river. It is crosscut more than 10 times by a single ENVISAT track over a hundred of km. We have determined time series of water levelsat each of these crossings, called virtual stations (VS), hence slopes of the flow line. Using the discharge series computed by Paiva et al. (2013) between 1998 and 2009, Paris et al. (submitted) determined at each VS a rating curve relating these simulated discharge with the ENVISAT height series. One parameter of these rating curves is the zero-flow depth Z 0 . We show that it is possible to explain the spatial and temporal variations of the water surface slope in terms of hydrodynamical response of the longitudinal changes of the river bed geometry given by the successive values of Z 0 . Our experiment is based on an effective, single thread representation of a braided river, realistic values for the Manning coefficient and river widths picked up on JERS images. This study confirms that simulated flow lines are consistent with water surface elevations (WSE) and slopes gained by satellite altimetry. Hydrodynamical signatures are more visible where the river bed geometry varies significantly, and for reaches with a strong downstream control. Therefore, this study suggests that the longitudinal variations of the slope might be an interesting criteria for the question of river segmentation into elementary reaches for the SWOT mission which will provide continuous measurements of the water surface elevation, the slope and the reach width.
Hydraulic geometry of river cross sections; theory of minimum variance

USGS Publications Warehouse

Williams, Garnett P.

1978-01-01

This study deals with the rates at which mean velocity, mean depth, and water-surface width increase with water discharge at a cross section on an alluvial stream. Such relations often follow power laws, the exponents in which are called hydraulic exponents. The Langbein (1964) minimum-variance theory is examined in regard to its validity and its ability to predict observed hydraulic exponents. The variables used with the theory were velocity, depth, width, bed shear stress, friction factor, slope (energy gradient), and stream power. Slope is often constant, in which case only velocity, depth, width, shear and friction factor need be considered. The theory was tested against a wide range of field data from various geographic areas of the United States. The original theory was intended to produce only the average hydraulic exponents for a group of cross sections in a similar type of geologic or hydraulic environment. The theory does predict these average exponents with a reasonable degree of accuracy. An attempt to forecast the exponents at any selected cross section was moderately successful. Empirical equations are more accurate than the minimum variance, Gauckler-Manning, or Chezy methods. Predictions of the exponent of width are most reliable, the exponent of depth fair, and the exponent of mean velocity poor. (Woodard-USGS)
Detailed measured sections, cross sections, and paleogeographic reconstructions of the upper cretaceous and lower tertiary nonmarine interval, Wind River Basin, Wyoming: Chapter 10 in Petroleum systems and geologic assessment of oil and gas resources in the Wind River Basin Province, Wyoming

USGS Publications Warehouse

Johnson, Ronald C.

2007-01-01

Detailed measured sections and regional stratigraphic cross sections are used to reconstruct facies maps and interpret paleogeographic settings for the interval from the base of Upper Cretaceous Mesaverde Formation to top of lower member of the Paleocene Fort Union Formation in the Wind River Basin, Wyoming. The Mesaverde Formation spans the time during which the Upper Cretaceous seaway retreated eastward out of central Wyoming in Campanian time and the initial stages of the Lewis transgression in earliest Maastrichtian time. This retreat stalled for a considerable period of time during deposition of the lower part of the Mesaverde, creating a thick buildup of marginal marine sandstones and coaly coastal plain deposits across the western part of the basin. The Lewis sea transgressed into the northeast part of Wind River Basin, beginning in early Maastrichtian time during deposition of the Teapot Sandstone Member of the Mesaverde Formation. The Meeteetse Formation, which overlies the Teapot, was deposited in a poorly-drained coastal plain setting southwest of the Lewis seaway. The Lewis seaway, at maximum transgression, covered much of the northeast half of the Wind River Basin area but was clearly deflected around the present site of the Wind River Range, southwest of the basin, providing the first direct evidence of Laramide uplift on that range. Uplift of the Wind River Range continued during deposition of the overlying Maastrichtian Lance Formation. The Granite Mountains south of the basin also became a positive feature during this time. A rapidly subsiding trough during the Maastrichtian time formed near the presentday trough of the Wind River Basin in which more than 6,000 feet of Lance was deposited. The development of this trough appears to have begun before the adjacent Owl Creek Mountains to the north started to rise; however, a muddy facies in the upper part of Lance in the deep subsurface, just to the south, might be interpreted to indicate that the Cretaceous Cody Shale was being eroded off a rising Owl Creek Mountains in latest Cretaceous time. The Paleocene Fort Union Formation unconformably overlies older units but with only slight angular discordance around much of the margins of the Wind River Basin. Pre-Fort Union erosion was most pronounced toward the Wind River Range to the southwest, where the Fort Union ultimately overlies strata as old as the upper part of the Cretaceous Cody Shale. The unconformity appears to die out toward the basin center. Coal-forming mires developed throughout the western part of the basin near the beginning of the Paleocene. River systems entering the basin from the Wind River Range to the southwest and the Granite Mountains to the south produced areas of sandy fluvial deposition along mountain fronts. A major river system appears to have entered the basin from about the same spot along the Wind River Range throughout much of the Paleocene, probably because it became incised and could not migrate laterally. The muddy floodplain facies that developed along the deep basin trough during latest Cretaceous time, expanded during the early part of the Paleocene. Coal-forming mires that characterize part of the lower Fort Union Formation reached maximum extent near the beginning of the late Paleocene and just prior to the initial transgression of Lake Waltman. From the time of initial flooding, Lake Waltman expanded rapidly, drowning the coal-forming mires in the central part of the basin and spreading to near basin margins. Outcrop studies along the south margin of the basin document that once maximum transgression was reached, the lake was rapidly pushed basinward and replaced by fluvial environments.
Monitoring and Risk Identification Caused by High Water, Floods and Erosion Processes in Urban Part of Sava Riverbed

NASA Astrophysics Data System (ADS)

Oskoruš, D.; Miković, N.; Ljevar, I.

2012-04-01

Riverbed erosion and bottom deepening are part of natural fluvial processes in the upper stream of Sava River. The increasing gradient of those changes is interconnected with the level of human influence in the river basin and riverbed as well. In time period of last forty years the consequences of riverbed erosion are become serious as well as dangerous and they threaten the stability of hydro technical structures. The increasing value of flow velocity in riverbed in urban part of river section during high water level, mud and debris flow during the floods as well, is especially dangerous for old bridges. This paper contains result of velocity measurements during high waters taken by Hydrological Service of Republic Croatia, load transport monitoring during such events and cross sections in some vulnerable location. In this paper is given one example of Jakuševac railway bridge in Zagreb, heavily destroyed during high water event on the 30 March 2009., recently reconstructed by "Croatian Railways" company. Keywords: Riverbed erosion, flow velocity, mud and debris flow, risk identification, stability of bridges
Water quality of the tidal Potomac River and Estuary; hydrologic data report, 1981 water year, with a section on collection and analysis of chlorophyll-a

USGS Publications Warehouse

Blanchard, Stephen F.; Coupe, Richard H.; Woodward, Joan C.

1982-01-01

This report contains data on the physical and chemical properties measured in the Tidal Potomac River and Estuary during the 1981 water year. Data were collected at least weekly at five stations, and periodically at 15 stations and at two other stations near the mouth of the Potomac River in Chesapeake Bay. Each of the five stations represent a cross section at which the transport of selected dissolved and suspended materials can be computed. The remaining 17 stations are locations at which data were collected for special studies of selected phenomena, such as salt water migration and dissolved oxygen dynamics. Samples were routinely analyzed for chlorophyll-a, nitrogen, pheophytin, phosphorus, silica and suspended sediment. Additional samples were analyzed for adenosine triphosphate, algal growth potential, alkalinity, calcium, chloride, dissolved-solids residue, fluoride, iron, manganese, magnesium, nitrifying bacteria, organic carbon, potassium, seston, sodium, and sulfate. In addition, in-situ measurements of dissolved oxygen, specific conductance, pH, temperature, solar radiation, and secchi disk transparency were made. (USGS)
Initial river test of a monostatic RiverSonde streamflow measurement system

USGS Publications Warehouse

Teague, C.C.; Barrick, D.E.; Lilleboe, P.M.; Cheng, R.T.; ,

2003-01-01

A field experiment was conducted on May 7-8, 2002 using a CODAR RiverSonde UHF radar system at Vernalis, California on the San Joaquin River. The monostatic radar configuration on one bank of the river, with the antennas looking both upriver and downriver, provided very high-quality data. Estimates of both along-river and cross-river surface current were generated using several models, including one based on normal-mode analysis. Along-river surface velocities ranged from about 0.6 m/s at the river banks to about 1.0 m/s near the middle of the river. Average cross-river surface velocities were 0.02 m/s or less.
Risk assessment on an Argentinean road with a dynamic traffic simulator

NASA Astrophysics Data System (ADS)

Voumard, Jérémie; Baumann, Valérie; Jaboyedoff, Michel; Derron, Marc-Henri; Penna, Ivanna

2014-05-01

The National Route 7 in Argentina is one of the most important corridors crossing the Andean Cordillera. It concentrates most of the traffic related to the Southern Common Market (MERCOSUR), it also connects Mendoza city (the fourth most populated in Argentina) with Santiago de Chile (the Chile capital city), and is used by tourists to access to the Aconcagua National park, Puente del Inca natural monument, skiing resorts, and to local displacements for the villages along the Mendoza valley. The road crosses the Andes through the Mendoza river valley at an elevation between 2'000 and 3'000 m. The traffic (2500 vehicles/day) is composed of motorcycles, cars and pickup trucks, trucks without trailer, buses, and semi-trailer trucks. Debris flows developed along tributaries of the Mendoza River, and due to remobilization of talus materials, impact frequently the road, causing traffic disruptions, bridges damages, etc. Rock falls detached from highly fractured outcrops also impact frequently the road, causing sometimes casualties. The aim of this study is to evaluate risk along sections of the National Road 7 develop along the Mendoza river, using a dynamic traffic simulator based on MATLAB© routine. The dynamic traffic simulator developed for natural hazards events on roads consider different scenarios based on traffic speeds, vehicle types, interactions types, road properties and natural processes. Here we show that vehicle types and traffic variations may influence the risk estimation. The analyzed risk on several critical sections of the National Route 7 demonstrates that risk may significantly increase: 1) on sinuous sections, steep sections and because of road conditions changes (exit of tunnel, bridges, road width, etc.) because of decreasing vehicle speed, particularly with semi-trailer trucks; 2) when an event, such a debris flow, occurs and generates a vehicle tailback increasing their duration presence in the risk area.

Occupational Stress and Management Strategies of Secondary School Principals in Cross River State, Nigeria

ERIC Educational Resources Information Center

Anyanwu, Joy; Ezenwaji, Ifeyinwa; Okenjom, Godian; Enyi, Chinwe

2015-01-01

The study aimed at finding out sources and symptoms of occupational stress and management strategies of principals in secondary schools in Cross River State, Nigeria. Descriptive survey research design was adopted for the study with a population of 420 principals (304 males and 116 females) in secondary schools in Cross River State, Nigeria. Three…
On the Far Bank: The Effects of Gap Crossing on Operational Reach

DTIC Science & Technology

2015-05-25

operations. 15. SUBJECT TERMS United States Army; Gap crossing; River crossing; Operational reach; Operation Market -Garden; Operation Plunder...3 Case Study: Operation Market Garden...successful gap crossing. The Allied failure in Operation Market -Garden during World War II showed that successfully crossing a river such as the Waal does
Simulation of hydraulic characteristics in the white sturgeon spawning habitat of the Kootenai River near Bonners Ferry, Idaho

USGS Publications Warehouse

Berenbrock, Charles

2005-01-01

Hydraulic characterization of the Kootenai River, especially in the white sturgeon spawning habitat reach, is needed by the Kootenai River White Sturgeon Recovery Team to promote hydraulic conditions that improve spawning conditions for the white sturgeon (Acipenser transmontanus) in the Kootenai River. The decreasing population and spawning failure of white sturgeon has led to much concern. Few wild juvenile sturgeons are found in the river today. Determining the location of the transition between backwater and free-flowing water in the Kootenai River is a primary focus for biologists who believe that hydraulic changes at the transition affect the location where the sturgeon choose to spawn. The Kootenai River begins in British Columbia, Canada, and flows through Montana, Idaho, and back into British Columbia. The 65.6-mile reach of the Kootenai River in Idaho was studied. The study area encompasses the white sturgeon spawning reach that has been designated as a critical habitat. A one-dimensional hydraulic-flow model of the study reach was developed, calibrated, and used to develop relations between hydraulic characteristics and water-surface elevation, discharge, velocity, and backwater extent. The model used 164 cross sections, most of which came from a previous river survey conducted in 2002-03. The model was calibrated to water-surface elevations at specific discharges at five gaging stations. Calibrated water-surface elevations ranged from about 1,743 to about 1,759 feet, and discharges used in calibration ranged from 5,000 to 47,500 cubic feet per second. Model calibration was considered acceptable when the difference between measured and simulated water-surface elevations was ?0.15 foot or less. Measured and simulated average velocities also were compared. These comparisons indicated agreement between measured and simulated values. The location of the transition between backwater and free-flowing water was determined using the calibrated model. The model was used to simulate hydraulic characteristics for a range of water-surface elevations from 1,741 to 1,762 feet and discharges from 4,000 to 75,000 cubic feet per second. These simulated hydraulic characteristics were used to develop a three-parameter relation-discharge in the study reach, water-surface elevation at Kootenai River at Porthill gaging station (12322000), and the location of the transition between backwater and free-flowing water. Simulated hydraulic characteristics produced backwater locations ranging from river mile (RM) 105.6 (Porthill) to RM 158 (near Crossport), a span of about 52 miles. However, backwater locations from measured data ranged primarily from RM 152 to RM 157, a 5-mile span. The average backwater location from measured data was at about RM 154. Three-parameter relations also were developed for determining the amount of discharge in the Shorty Island side channel and average velocity at selected cross sections in the study reach. Simulated discharge for the side channel relative to measured data ranged from 0 to about 5,500 cubic feet per second, and simulated average velocity relative to measured data ranged from 0 to about 3.5 feet per second. Relations using other hydraulic, sediment/incipient motion, ecological, and biological characteristics also could be developed. The relations also can be used in real time by accessing data from the Web. Discharge and stage data for two gaging stations, Tribal Hatchery (12310100) and Porthill (12322500), are available from the Idaho U.S. Geological Survey web page (URL: http://waterdata.usgs.gov/id/nwis/current/?type=flow). Because the coordinate axes of the three-parameter relations use discharge from the Tribal Hatchery gaging station and water-surface elevation from the Porthill gaging station, the location of the transition between backwater and free-flowing water can be determined for current conditions using the real-time data. Similarly, discharge in the Shorty Island side channel and (or) average velocity at selected cross sections also can be determined for current conditions.
Childhood Malnutrition is Associated with Maternal Care During Pregnancy and Childbirth: A Cross-Sectional Study in Bauchi and Cross River States, Nigeria.

PubMed

Hamel, Candyce; Enne, Joseph; Omer, Khalid; Ayara, Ndem; Yarima, Yahaya; Cockcroft, Anne; Andersson, Neil

2015-02-20

Malnutrition remains an important cause of childhood morbidity and mortality; the levels of childhood malnutrition in Nigeria are among the highest in the world. The literature supports many direct and indirect causes of malnutrition, but few studies have examined the link between maternal care during pregnancy and childbirth and childhood malnutrition. This study examines this potential link in Bauchi and Cross River states in Nigeria. In 2011, a household survey collected information about children under four years old and their mothers' last pregnancy. Trained fieldworkers measured mid-upper arm circumference (MUAC) of children aged 6-47 months. We examined associations with childhood malnutrition in bivariate and multivariate analysis. Some 4.4% of 3643 children in Cross River, and 14.7% of 2706 in Bauchi were malnourished (MUAC z-score). In both states, a child whose mother had fewer than four government antenatal care visits was more likely to be malnourished (Cross River: OR 1.85, 95%CIca 1.33-2.55; Bauchi: OR 1.29, 95%CIca 1.02-1.63). In Bauchi, a child whose mother who rarely or never discussed pregnancy and childbirth with her husband (OR 1.34, 95%CIca 1.07-1.68), and who did not have her last delivery attended by a skilled health worker was more likely to be malnourished (OR 1.50, 95%CIca 1.09-2.07). These findings, if confirmed in other studies, suggest that poor care of women in pregnancy and childbirth could pose a longer term risk to the health of the child, as well as increasing immediate risks for both mother and child. Significance for public healthChildhood malnutrition is a public health priority, accounting for almost 1/5 of global disease burden among children under five years old. Many studies have examined risk factors for childhood malnutrition, but few have examined the link between maternal care during pregnancy and childbirth and childhood malnutrition. This study, albeit a cross-sectional design, provides evidence of a link between poor care during pregnancy and childbirth and childhood malnutrition in two states of Nigeria. This is important for public health because it suggests another benefit of caring for women during pregnancy and childbirth. This could not only reduce maternal and child perinatal mortality, but also have benefits for the longer-term health and development of children. This finding could be useful for paternal advocacy; it may motivate men to support their wives during pregnancy and childbirth since through this support, fathers can also protect the future development of their children.
Characterization of Interactions between Surface Water and Near-Stream Groundwater along Fish Creek, Teton County, Wyoming, by Using Heat as a Tracer

USGS Publications Warehouse

Eddy-Miller, Cheryl A.; Wheeler, Jerrod D.; Essaid, Hedeff I.

2009-01-01

Fish Creek, a tributary of the Snake River, is about 25 river kilometers long and is located in Teton County in western Wyoming near the town of Wilson. Local residents began observing an increase in the growth of algae and aquatic plants in the stream during the last decade. Due to the known importance of groundwater to surface water in the area, the U.S. Geological Survey (USGS), in cooperation with the Teton Conservation District, conducted a study to characterize the interactions between surface water and near-stream groundwater along Fish Creek. The study has two main objectives: (1) develop an improved spatial and temporal understanding of water flow (fluxes) between surface water and groundwater, and (2) use a two-dimensional groundwater-flow and heat-transport model to interpret observed temperature and hydraulic-head distributions and to describe groundwater flow near Fish Creek. The study is intended to augment hydrologic information derived from previously published results of a seepage investigation on Fish Creek. Seepage measurements provide spatially averaged gains and losses over an entire reach for one point in time, whereas continuous temperature and water-level measurements provide continuous estimates of gain and loss at a specific location. Stage, water-level, and temperature data were collected from surface water and from piezometers completed in an alluvial aquifer at three cross sections on Fish Creek at Teton Village, Resor's Bridge, and Wilson from October 2004 to October 2006. The flow and energy (heat) transport model VS2DH was used to simulate flow through the streambed of Fish Creek at the Teton Village cross section from April 15 to October 14, 2006, (183 recharge periods) and at the Resor's Bridge and Wilson cross sections from June 6, 2005, to October 14, 2006 (496 recharge periods). A trial-and-error technique was used to determine the best match between simulated and measured data. These results were then used to calibrate the cross-sectional models and determine horizontal and vertical hydraulic conductivities. The fluxes of groundwater into the stream or fluxes of stream water into the alluvial aquifer were estimated by using the calibrated VS2DH model for each cross section. Results of the simulations indicated that surface water/groundwater interaction and hydraulic properties were different at the three cross sections. At the most upstream cross section, Teton Village, Fish Creek flowed intermittently and continually gained relatively large quantities of water from April through September. During other times of the year, the stream was dry near the cross section. Saturated hydraulic conductivity set at 1x10-4 m/s in both the horizontal and vertical directions resulted in the best match between simulated and measured temperatures. The Resor's Bridge cross section, about midway between the other two cross sections, was near the point where perennial flow begins. At this cross section, the stream gained water from groundwater during high flow in late spring and summer, was near equilibrium with groundwater during August and September, and lost water to groundwater during the remainder of the year. Horizontal hydraulic conductivity set at 5x10-5 m/s and vertical hydraulic conductivity set at 1x10-5 m/s resulted in the best match between simulated and measured temperatures. The Wilson cross section, the most downstream site, was at USGS streamflow-gaging station 13016450. This part of the stream is perennial and was almost always gaining a small volume of water from groundwater. Saturated hydraulic conductivity set at 1x10-4 m/s in the horizontal direction and at 5x10-6 m/s in the vertical direction resulted in the best match between simulated and measured temperatures. Quantitative values of the flux from groundwater into surface water were estimated by using VS2DH and ranged from 1.1 to 6.6 cubic meters per day (m3/d) at the Teton Village cross section, from -3.8 to 7.4 m3/d at t
Sedimentation Impacts Modeling for the Lower Elwha River

NASA Astrophysics Data System (ADS)

Beggs, M.; Kosaka, M.; Sigel, A.; Vandermause, R.; Lauer, J. W.

2012-12-01

The removal of Glines Canyon and Elwha Dams from the Elwha River, northwest Washington, is intended to restore natural geomorphic and ecological processes to the Elwha River basin. Prior to the start of dam removal, over 16 million cubic meters of sediment had accumulated in the reservoirs above the two dams. As dam removal progresses, a portion of this sediment will erode and then be deposited on the downstream river bed and floodplain. To address uncertainty in downstream response to the project, the United States Bureau of Reclamation is implementing an adaptive management plan that relies upon continuous monitoring of water levels at a set of stream gages along the river. To interpret the monitoring data and allow for rapid assessment of the rate of downstream sedimentation, we developed rating curves at several locations along the lower Elwha River. The curves consider a range of possible sedimentation scenarios, each involving different sedimentation levels and/or locations. One scenario considers sedimentation primarily in the river channel, another considers sedimentation primarily on the floodplain, and a third considers both possibilities in tandem. We modeled these scenarios using two separate approaches. First, we modified the cross sections in an existing U.S. Army Corps of Engineers HEC-RAS model to represent possible changes associated with geomorphic adjustment to the dam removals. In-channel sedimentation was assumed to occur as a constant fraction of the bankfull depth at any given section, thereby focusing geomorphic change in relatively deep pool areas. In the HEC-RAS model, off-channel sedimentation was assumed uniform. The HEC-RAS model showed that both low-flow and flood hydraulics are much more sensitive to plausible levels of in-channel sedimentation than to plausible levels of overbank sedimentation. The wide floodplain, complex secondary channels, and geomorphic evolution since the original cross sections were surveyed raise some questions regarding the validity of our 1-D HEC-RAS results and motivated our second approach, which involved developing an independent 2-D hydraulic model using the U.S. Bureau of Reclamation SRH-2d program. This model had the added benefit of being able to utilize more recently surveyed bathymetric and topographic data. The 2-D model was used to improve the representation of spatial variability of likely floodplain sedimentation. For this, we used a preliminary run of the program to characterize the water surface elevation for a typical flood event. We then used the modeled water surface as an input for an eight direction pour point determination of flow direction in ArcGIS. This allowed us to approximate the flow distance from the main channel along streamlines crossing the floodplain. Using observed levee morphology, we developed an ad-hoc exponential function for overbank sedimentation as a function of flow distance from the channel. This tended to focus deposition on natural levees at the upstream side of point bars or meander necks. Despite the more narrowly focused zone of floodplain sedimentation, however, the results were consistent with the 1-D result that in-channel sedimentation is like to have a greater relative impact on system-wide hydraulics than does overbank sedimentation.
An Evaluation of the Science Education Component of the Cross River State Science and Technical Education Project

ERIC Educational Resources Information Center

Ekuri, Emmanuel Etta

2012-01-01

The Cross River State Science and Technical Education Project was introduced in 1992 by edict number 9 of 20 December 1991, "Cross River State Science and Technical Education Board Edit, 20 December, 1991", with the aim of improving the quality of science teaching and learning in the state. As the success of the project depends…
Youth Empowerment in Higher Education for Sustainable Development of Developing Communities in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ekpiken, William E.; Ukpabio, Godfrey U.

2015-01-01

This paper was an attempt to examine youth empowerment in higher education for sustainable development of developing communities in Cross River State in Nigeria. In Cross River State developing communities, youths are in the majority and form a very strong formidable force in the society we live, study, but are not empowered while in school nor…
3. ENVIRONMENT, FROM SOUTH, SHOWING RIVER ROAD RIDGE CARRYING CASSELMAN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. ENVIRONMENT, FROM SOUTH, SHOWING RIVER ROAD RIDGE CARRYING CASSELMAN RIVER ROAD OVER CASSELMAN RIVER - River Road Bridge, Crossing Casselman River on Casselman River Road, Grantsville, Garrett County, MD
Physically based method for measuring suspended-sediment concentration and grain size using multi-frequency arrays of acoustic-doppler profilers

USGS Publications Warehouse

Topping, David J.; Wright, Scott A.; Griffiths, Ronald; Dean, David

2014-01-01

As the result of a 12-year program of sediment-transport research and field testing on the Colorado River (6 stations in UT and AZ), Yampa River (2 stations in CO), Little Snake River (1 station in CO), Green River (1 station in CO and 2 stations in UT), and Rio Grande (2 stations in TX), we have developed a physically based method for measuring suspended-sediment concentration and grain size at 15-minute intervals using multifrequency arrays of acoustic-Doppler profilers. This multi-frequency method is able to achieve much higher accuracies than single-frequency acoustic methods because it allows removal of the influence of changes in grain size on acoustic backscatter. The method proceeds as follows. (1) Acoustic attenuation at each frequency is related to the concentration of silt and clay with a known grain-size distribution in a river cross section using physical samples and theory. (2) The combination of acoustic backscatter and attenuation at each frequency is uniquely related to the concentration of sand (with a known reference grain-size distribution) and the concentration of silt and clay (with a known reference grain-size distribution) in a river cross section using physical samples and theory. (3) Comparison of the suspended-sand concentrations measured at each frequency using this approach then allows theory-based calculation of the median grain size of the suspended sand and final correction of the suspended-sand concentration to compensate for the influence of changing grain size on backscatter. Although this method of measuring suspended-sediment concentration is somewhat less accurate than using conventional samplers in either the EDI or EWI methods, it is much more accurate than estimating suspended-sediment concentrations using calibrated pump measurements or single-frequency acoustics. Though the EDI and EWI methods provide the most accurate measurements of suspended-sediment concentration, these measurements are labor-intensive, expensive, and may be impossible to collect at time intervals less than discharge-independent changes in suspended-sediment concentration can occur (< hours). Therefore, our physically based multi-frequency acoustic method shows promise as a cost-effective, valid approach for calculating suspended-sediment loads in river at a level of accuracy sufficient for many scientific and management purposes.
Hydraulic, geomorphic, and trout habitat conditions of the Lake Fork of the Gunnison River in Hinsdale County, Lake City, Colorado, Water Years 2010-2011

USGS Publications Warehouse

Williams, Cory A.; Richards, Rodney J.; Schaffrath, Keelin R.

2015-01-01

Sediment mobility is an important process for flushing fine sediments from within the gravel frameworks. Evaluations of channel and flow characteristics at cross-section locations 2–8 show a range of streambed mobility. In general, boundary shear stress and streambed mobility increase with increases in streamflow. Within the cross sections, the greatest boundary shear stress occurs towards the center of the channel. Reach-scale assessment of sediment mobility in the lower reach shows increased streambed mobility. This is due in part to smaller grain sizes in the lower reach, but may also reflect the greater extent of channel alterations, specifically the temporary berms constructed by CDOT in the late 1980s and 1990s, present in this reach.
Fire chronology and windstorm effects on persistence of a disjunct oak-shortleaf pine community

Treesearch

Michael D. Jones; Marlin L. Bowles

2012-01-01

We investigated effects of a human-altered fire regime and wind storms on persistence of disjunct oak-shortleaf pine vegetation occurring along 5.5 km of xeric habitat on the east bluffs of the Mississippi River in Union County, IL. In 2009, we resampled vegetation transects established in seven stands in 1954 and obtained 26 cross sections containing fire scars from...
Bedload transport in a river confluence

NASA Astrophysics Data System (ADS)

Martín-Vide, J. P.; Plana-Casado, A.; Sambola, A.; Capapé, S.

2015-12-01

The confluence of the regulated Toltén River and its tributary the unregulated Allipén (south of Chile) has proved dynamic in the last decade. Daily bedload measurements with a Helley-Smith sampler, bed surveys, and grain-size distributions of the two rivers are obtained from a field campaign that lasts 3 months in high-flow season. The goals are to quantify total bedload and to understand the balance between tributary and main river and the bedload distribution in space and texture. The bedload transport varies 200-fold, with a maximum of 5000 t/day. The discharge varies five-fold, with a maximum of 900 m3/s. Two-thirds of the total bedload volume are transported through the deeper area of the cross section and gravel is predominant (64%). Average bedload volumes in the confluence seem unbalanced in favour of the tributary. Main river bedload transport is predominantly at below-capacity conditions, while the tributary bedload transport is at-capacity conditions. This is deemed the main reason of inaccuracy of the bedload predictors. The roles of entrainment into suspension, helical flow, partial transport, and mobile armour are discussed.
Route-Specific Passage and Survival of Steelhead Kelts at The Dalles and Bonneville Dams, 2012 - Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rayamajhi, Bishes; Ploskey, Gene R.; Woodley, Christa M.

2013-07-31

This study was mainly focused on evaluating the route-specific passage and migration success of steelhead kelts passing downstream through The Dalles Dam (TDA) and Bonneville Dam (BON) at Columbia River (CR) river kilometers 309 and 234 respectively. Oregon Department of Fish and Wildlife (ODFW) personnel collected, tagged and released out-migrating steelhead kelts in the tributaries of the Deschutes River, 15 Mile Creek and Hood River between April 14 and June 4, 2012. A PIT tag was injected into each kelt’s dorsal sinus whereas a Juvenile Salmon Acoustic Telemetry System (JSATS) acoustic micro-transmitter was attached to an external FLoy T-bar tagmore » and inserted into the dorsal back musculature using a Floy tagging gun. JSATS cabled arrays were deployed at TDA and BON and autonomous node arrays were deployed near Celilo, Oregon (CR325); the BON forebay (CR236); the BON tailrace (CR233); near Knapp, Washington (CR156); and near Kalama, Washington (CR113) to monitor the kelts movement while passing through the dams and above mentioned river cross-sections.« less
Cumulative River Dynamic Assessment using Topo-Hydrographical High Definition Surveying in the Danube River area - Km 347-Km344

NASA Astrophysics Data System (ADS)

Nichersu, Iulian; Mierla, Marian; Trifanov, Cristian

2013-04-01

Cumulative River Dynamic Assessment using Topo-Hydrographical High Definition Surveying in the Danube River area - Km 347-Km344 Iulian NICHERSU, Cristian TRIFANOV, Marian MIERLA The purpose of this paper is to depict and illustrate the benefits of Topo-Hydrographical High Definition Surveying (THHDS), also known as 3D multi-beam scanning, on a topo-hydrological survey application in Danube Valley. This research investigates the evolution of Danube river dynamics. We start with cross-sections made in 2002, 2007 and 2010 in this area and we coupled with 2012 THHDS. 3D multi-beam scanning method of data acquisition improve the spatial hydrological model and offers better dynamics assessment for future studies, considering that this area is carried out dredging works to improve navigation conditions - THHDS technique true modeling capabilities have applications in hydrotechnical works. Dynamics stands out on all 3 axes and cartographic documents have used both the 1930, 1950, and orthophoto images taken during flight to obtain the 3D model of the floodplain through LIDAR method, in 2007.
Coarse sediment transport dynamics at three spatial scales of bedrock channel bed complexity

NASA Astrophysics Data System (ADS)

Goode, J. R.; Wohl, E.

2007-12-01

Rivers incised into bedrock in fold-dominated terrain display a complex bed topography that strongly interacts with local hydraulics to produce spatial differences in bed sediment flux. We used painted tracer clasts to investigate how this complex bed topography influences coarse sediment transport at three spatial scales (reach, cross- section and grain). The study was conducted along the Ocoee River gorge, Tennessee between the TVA Ocoee #3 dam and the 1996 Olympic whitewater course. The bed topography consists of undulating bedrock ribs, which are formed at a consistent strike to the bedding and cleavage of the metagreywake and phyllite substrate. Ribs vary in their orientation to flow (from parallel to oblique) and amplitude among three study reaches. These bedrock ribs create a rough bed topography that substantially alters the local flow field and influences reach- scale roughness. In each reach, 300 tracer clasts were randomly selected from the existing bed material. Tracer clasts were surveyed and transport distances were calculated after five scheduled summer releases and a suite of slightly larger but sporadic winter releases. Transport distances were examined as a function of rib orientation and amplitude (reach scale), spatial proximity to bedrock ribs and standard deviation of the bed elevation (cross- section scale), and whether clasts were hydraulically shielded by surrounding clasts, incorporated in the armour layer, imbricated, and/or existed in a pothole, in addition to size and angularity. At the reach scale, where ribs are parallel to flow, lower reach-scale roughness leads to greater sediment transport capacity, sediment flux and transport distances because transport is uninhibited in the downstream direction. Preliminary results indicate that cross section scale characteristics of bed topography exert a greater control on transport distances than grain size.
Organic contaminants associated with suspended sediment collected during five cruises of the Mississippi River and its principal tributaries, May 1988 to June 1990

USGS Publications Warehouse

Rostad, Colleen E.; Bishop, LaDonna M.; Ellis, Geoffrey S.; Leiker, Thomas J.; Monsterleet, Stephanie G.; Pereira, Wilfred E.

2004-01-01

Suspended-sediment samples were obtained from sites along the Mississippi River and its principal tributaries to determine the presence of halogenated hydrophobic organic compounds on the suspended sediment smaller than 63 micrometers. Sample collection involved pumping discharge-weighted volumes of river water along a cross section of the river into a continuous-flow centrifuge to isolate the suspended sediment. The suspended sediment was analyzed by gas chromatography/mass spectrometry for pentachlorobenzene, hexachlorobenzene, pentachloroanisole, chlorothalonil, pentachlorophenol, dachthal, chlordane, nonachlor, and penta-, hexa-, hepta-, and octachlorobiphenyls. Samples collected during June 1989 and February-March 1990 also were analyzed for U.S. Environmental Protection Agency priority pollutants, including polycyclic aromatic hydrocarbons, phthalate esters, and triazines. Samples were collected at sites on the Mississippi River from above St. Louis, Missouri to below New Orleans, Louisiana, and on the Illinois, Missouri, Ohio, Wabash, Cumberland, Tennessee, White, Arkansas, and Yazoo Rivers. Masses of selected halogenated hydrophobic organic compounds associated with the suspended sediment at each site are presented in this report in tabular format, along with suspended-sediment concentration, water discharge, and organic-carbon content.
Flood-plain areas of the Mississippi River, mile 866.8 to mile 888.0, Minnesota

USGS Publications Warehouse

Carlson, George H.; Gue, Lowell C.

1980-01-01

Profiles of the regional flood, 500-year flood, and flood-protection elevation have been developed for a 21-mile reach of the Mississippi River. Areas flooded by the regional flood and by the 500-year flood were delineated by photogrammetric mapping techniques and are shown on seven large-scale map sheets. Over 1,300 acres of flood plain are included in the cities of Anoka, Champlin, Coon Rapids, Dayton, Ramsey and Elk River, and in unincorporated areas of Wright County. The flood-outline maps and flood profiles comprise data needed by local units of government to adopt, enforce, and administer flood-plain management regulations along the Mississippi River throughout the study reach. Streamflow data from two gaging stations provided the basis for definition of the regional and 500-year floods. Cross-section data obtained at 83 locations were used to develop a digital computer model of the river. Flood elevation and discharge data from the 1965 flood provided a basis for adjusting the computer model. Information relating the history of floods, formation of ice jams, and duration of flood elevations at Anoka and at Elk River are included.
Radiolarian biostratigraphy of the Quinn River Formation, Black Rock terrane, north-central Nevada: correlations with eastern Klamath terrane geology

USGS Publications Warehouse

Blome, C.D.; Reed, K.M.

1995-01-01

The Quinn River Formation, Black Rock terrane, Quinn River Crossing, is one of the few Nevadan sections of Permian and Triassic strata that are unaffected by Sonoman deformation. The formation consists of: 1) a basal tuff overlain by limestone and ferruginous dolomite, 2) interbedded radiolarian-bearing chert and argillite, 3) siltstone and carbonaceous shale, and 4) partly volcaniclastic rocks. All but the uppermost (barren) chert samples contain Late Permian radiolarian taxa. These radiolarians suggest that early Wordian conodonts reported from near the top of the chert and argillite unit are reworked. Poorly preserved Early(?) or Middle triassic radiolarians and Middle Triassic ammonites and pectenacid bivalves from the middle part of the volcaniclastic unit indicate the Early Triassic deposition cannot be documented at Quinn River. The ages of the Quinn River brachiopod, conodont, and radiolarian faunas resemble those of the Dekkas and Pit Formations, eastern Klamath terrane, northern California. The analogous Quinn River and eastern Klamath rock types and faunal ages, as well as similar hiatuses in their stratigraphic records, suggest that they may be lateral equivalents that formed in the same island-arc sedimentary basin. -from Authors
Preliminary hydraulic analysis and implications for restoration of Noyes Slough, Fairbanks, Alaska

USGS Publications Warehouse

Burrows, Robert L.; Langley, Dustin E.; Evetts, David M.

2000-01-01

The present-day channels of the Chena River and Noyes Slough in downtown Fairbanks, Alaska, were formed as sloughs of the Tanana River, and part of the flow of the Tanana River occupied these waterways. Flow in these channels was reduced after the completion of Moose Creek Dike in 1945, and flow in the Chena River was affected by regulation from the Chena River Lakes Flood Control Project, which was completed in 1980. In 1981, flow in the Chena River was regulated for the first time by Moose Creek Dam, located about 20 miles upstream from Fairbanks. Constructed as part of the Chena River Lakes Flood Control Project, the dam was designed to reduce maximum flows to 12,000 cubic feet per second in downtown Fairbanks. Cross-section measurements made near the entrance to Noyes Slough show that the channel bed of the Chena River has been downcutting, thereby reducing the magnitude and duration of flow in the slough. Consequently the slough slowly is drying up. The slough provides habitat for wildlife such as ducks, beaver, and muskrat and is a fishery for anadromous and other resident species. Beavers have built 10 dams in the slough. Declining flow in the slough may endanger the remaining habitat. Residents of the community wish to restore flow in Noyes Slough to create a clean, flowing waterway during normal summer flows. The desire is to enhance the slough as a fishery and habitat for other wildlife and for recreational boating. During this study, existing and new data were compiled to determine past and present hydraulic interaction between the Chena River and Noyes Slough. The U.S. Army Corps of Engineers Hydrologic Engineering Center River Analysis System (HECRAS) computer program was used to construct a model to use in evaluating alternatives for increasing flow in the slough. Under present conditions, the Chena must flow at about 2,400 cubic feet per second or more for flow to enter Noyes Slough. In an average year, water flows in Noyes Slough for 106 days during the open-water season, and maximum flow is about 1,050 cubic feet per second. The model was used to test a single method of increasing flow in Noyes Slough. A modified channel 40 feet wide and about 2 feet deeper within the existing slough channel was simulated by changing the cross-section geometry in the HECRAS model. The resulting model showed that flow in such a modified slough channel would begin at a flow of about 830 cubic feet per second in the Chena River and would increase to a maximum flow of about 1,440 cubic feet per second. In an average year, flow would continue for 158 days during the open-water season. Theoretically, enlarging the slough channel by lowering its bed could increase flow, but other solutions are possible. Possible obstacles to excavating the channel, such as bridges and utility crossings, and the destruction of desirable features such as beaver dams were not considered in the study. Further engineering and economic analyses would be needed to assess the cost of excavation and future maintenance of the modified channel. A computer-modeling program such as HECRAS may provide a means for testing other solutions.

River salinity on a mega-delta, an unstructured grid model approach.

NASA Astrophysics Data System (ADS)

Bricheno, Lucy; Saiful Islam, Akm; Wolf, Judith

2014-05-01

With an average freshwater discharge of around 40,000 m3/s the BGM (Brahmaputra Ganges and Meghna) river system has the third largest discharge worldwide. The BGM river delta is a low-lying fertile area covering over 100,000 km2 mainly in India and Bangladesh. Approximately two-thirds of the Bangladesh people work in agriculture and these local livelihoods depend on freshwater sources directly linked to river salinity. The finite volume coastal ocean model (FVCOM) has been applied to the BGM delta in order to simulate river salinity under present and future climate conditions. Forced by a combination of regional climate model predictions, and a basin-wide river catchment model, the 3D baroclinic delta model can determine river salinity under the current climate, and make predictions for future wet and dry years. The river salinity demonstrates a strong seasonal and tidal cycle, making it important for the model to be able to capture a wide range of timescales. The unstructured mesh approach used in FVCOM is required to properly represent the delta's structure; a complex network of interconnected river channels. The model extends 250 km inland in order to capture the full extent of the tidal influence and grid resolutions of 10s of metres are required to represent narrow inland river channels. The use of FVCOM to simulate flows so far inland is a novel challenge, which also requires knowledge of the shape and cross-section of the river channels.
Field evaluation of the error arising from inadequate time averaging in the standard use of depth-integrating suspended-sediment samplers

USGS Publications Warehouse

Topping, David J.; Rubin, David M.; Wright, Scott A.; Melis, Theodore S.

2011-01-01

Several common methods for measuring suspended-sediment concentration in rivers in the United States use depth-integrating samplers to collect a velocity-weighted suspended-sediment sample in a subsample of a river cross section. Because depth-integrating samplers are always moving through the water column as they collect a sample, and can collect only a limited volume of water and suspended sediment, they collect only minimally time-averaged data. Four sources of error exist in the field use of these samplers: (1) bed contamination, (2) pressure-driven inrush, (3) inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration, and (4) inadequate time averaging. The first two of these errors arise from misuse of suspended-sediment samplers, and the third has been the subject of previous study using data collected in the sand-bedded Middle Loup River in Nebraska. Of these four sources of error, the least understood source of error arises from the fact that depth-integrating samplers collect only minimally time-averaged data. To evaluate this fourth source of error, we collected suspended-sediment data between 1995 and 2007 at four sites on the Colorado River in Utah and Arizona, using a P-61 suspended-sediment sampler deployed in both point- and one-way depth-integrating modes, and D-96-A1 and D-77 bag-type depth-integrating suspended-sediment samplers. These data indicate that the minimal duration of time averaging during standard field operation of depth-integrating samplers leads to an error that is comparable in magnitude to that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. This random error arising from inadequate time averaging is positively correlated with grain size and does not largely depend on flow conditions or, for a given size class of suspended sediment, on elevation above the bed. Averaging over time scales >1 minute is the likely minimum duration required to result in substantial decreases in this error. During standard two-way depth integration, a depth-integrating suspended-sediment sampler collects a sample of the water-sediment mixture during two transits at each vertical in a cross section: one transit while moving from the water surface to the bed, and another transit while moving from the bed to the water surface. As the number of transits is doubled at an individual vertical, this error is reduced by ~30 percent in each size class of suspended sediment. For a given size class of suspended sediment, the error arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration depends only on the number of verticals collected, whereas the error arising from inadequate time averaging depends on both the number of verticals collected and the number of transits collected at each vertical. Summing these two errors in quadrature yields a total uncertainty in an equal-discharge-increment (EDI) or equal-width-increment (EWI) measurement of the time-averaged velocity-weighted suspended-sediment concentration in a river cross section (exclusive of any laboratory-processing errors). By virtue of how the number of verticals and transits influences the two individual errors within this total uncertainty, the error arising from inadequate time averaging slightly dominates that arising from inadequate sampling of the cross-stream spatial structure in suspended-sediment concentration. Adding verticals to an EDI or EWI measurement is slightly more effective in reducing the total uncertainty than adding transits only at each vertical, because a new vertical contributes both temporal and spatial information. However, because collection of depth-integrated samples at more transits at each vertical is generally easier and faster than at more verticals, addition of a combination of verticals and transits is likely a more practical approach to reducing the total uncertainty in most field situatio
GSTARS computer models and their applications, part I: theoretical development

USGS Publications Warehouse

Yang, C.T.; Simoes, F.J.M.

2008-01-01

GSTARS is a series of computer models developed by the U.S. Bureau of Reclamation for alluvial river and reservoir sedimentation studies while the authors were employed by that agency. The first version of GSTARS was released in 1986 using Fortran IV for mainframe computers. GSTARS 2.0 was released in 1998 for personal computer application with most of the code in the original GSTARS revised, improved, and expanded using Fortran IV/77. GSTARS 2.1 is an improved and revised GSTARS 2.0 with graphical user interface. The unique features of all GSTARS models are the conjunctive use of the stream tube concept and of the minimum stream power theory. The application of minimum stream power theory allows the determination of optimum channel geometry with variable channel width and cross-sectional shape. The use of the stream tube concept enables the simulation of river hydraulics using one-dimensional numerical solutions to obtain a semi-two- dimensional presentation of the hydraulic conditions along and across an alluvial channel. According to the stream tube concept, no water or sediment particles can cross the walls of stream tubes, which is valid for many natural rivers. At and near sharp bends, however, sediment particles may cross the boundaries of stream tubes. GSTARS3, based on FORTRAN 90/95, addresses this phenomenon and further expands the capabilities of GSTARS 2.1 for cohesive and non-cohesive sediment transport in rivers and reservoirs. This paper presents the concepts, methods, and techniques used to develop the GSTARS series of computer models, especially GSTARS3. ?? 2008 International Research and Training Centre on Erosion and Sedimentation and the World Association for Sedimentation and Erosion Research.
Combining Envisat type and CryoSat-2 altimetry to inform hydrodynamic models

NASA Astrophysics Data System (ADS)

Schneider, Raphael; Nygaard Godiksen, Peter; Villadsen, Heidi; Madsen, Henrik; Bauer-Gottwein, Peter

2015-04-01

Hydrological models are developed and used for flood forecasting and water resources management. Such models rely on a variety of input and calibration data. In general, and especially in data scarce areas, remote sensing provides valuable data for the parameterization and updating of such models. Satellite radar altimeters provide water level measurements of inland water bodies. So far, many studies making use of satellite altimeters have been based on data from repeat-orbit missions such as Envisat, ERS or Jason or on synthetic wide-swath altimetry data as expected from the SWOT mission. This work represents one of the first hydrologic applications of altimetry data from a drifting orbit satellite mission, using data from CryoSat-2. We present an application where CryoSat-2 data is used to improve a hydrodynamic model of the Ganges and Brahmaputra river basins in South Asia set up in the DHI MIKE 11 software. The model's parameterization and forcing is mainly based on remote sensing data, for example the TRMM 3B42 precipitation product and the SRTM DEM for river and subcatchment delineation. CryoSat-2 water levels were extracted over a river mask derived from Landsat 7 and 8 imagery. After calibrating the hydrological-hydrodynamic model against observed discharge, simulated water levels were fitted to the CryoSat-2 data, with a focus on the Brahmaputra river in the Assam valley: The average simulated water level in the hydrodynamic model was fitted to the average water level along the river's course as observed by CryoSat-2 over the years 2011-2013 by adjusting the river bed elevation. In a second step, the cross section shapes were adjusted so that the simulated water level dynamics matched those obtained from Envisat virtual station time series. The discharge calibration resulted in Nash-Sutcliffe coefficients of 0.86 and 0.94 for the Ganges and Brahmaputra. Using the Landsat river mask, the CryoSat-2 water levels show consistency along the river and are in good accordance with other products, such as the SRTM DEM. The adjusted hydrodynamic model reproduced the average water level profile along the river channel with a higher accuracy than a model based on the SRTM DEM. Furthermore, the amplitudes as observed in Envisat virtual station time series could be reproduced fitting simple triangular cross section shapes. A hydrodynamic model prepared in such a way provides water levels at any point along the river and any point in time, which are consistent with the multi-mission altimetric dataset. This means it can for example be updated by assimilation of near real-time water level measurements from CryoSat-2 improving its flood forecasting capability.
Field testing of three bedload samplers' efficiency in a gravel-bed river, Spitsbergen

NASA Astrophysics Data System (ADS)

Rachlewicz, Grzegorz; Zwoliński, Zbigniew; Kociuba, Waldemar; Stawska, Monika

2017-06-01

A comparative study of the three bedload traps was accomplished to determine the effectiveness differences between the devices. The research was carried out in two transverse sections of the proglacial, gravel-bedded Scott River (SW Svalbard) using three devices to perform direct measurements of bedload transport in the river channels. Several samplers are used for field measurements, but none of them has gained widespread acceptance as a standard so far. The paper compares transport rates collected in three bedload samplers that differ in structure and functionality: i) a portable Helley-Smith, pressure-difference bedload sampler (H-S), ii) an anchored River Bedload Trap (RBT), and iii) the portable sampler used by the Polish Hydrological Services (PIHM type C). All three samplers are constructed using the same components: a frame made of thin stainless steel sheet and a nylon bag with the same (2 mm) mesh size (except PIHM). Measurements were conducted within three consecutive days in two cross sections, in the same vertical profiles and at the same time (at intervals of 30 and 60 min). Measurements of bedload transport and water velocity were performed simultaneously. In order to determine the effectiveness and representativeness of short-term measurements using particular devices, the masses of the samples were converted into a specific rate of bedload transport and compared to the results of long-term continuous measurement (24 h measurement cycle). The results confirm that both specific transport indicators and the mass of the samples collected by the tested devices show a significant variation. Generally, the highest mass and specific transport indicators were obtained using the H-S sampler. The RBT produced moderate transport rates, while the PIHM sampler gave the lowest rates. The bedload transport rate in a profile estimated on the short-term measurements was compared to results of the continuous measurements conducted in the same cross sections. In the 7 cases we obtained underestimation (to max. 10 times) and in the next 7 cases - overestimation (to max. 114 times). Only in four cases were the results of short-term measurements similar to the continuous ones. The results obtained from the RBT sampler show the smallest variability among all tested devices.
HDD proves effective in crossing French river

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-06-01

Gas de France is the primary transporter and distributor of natural gas in France, operating some 28,000 kilometers of gas pipelines. In 1996, Gas de France and Gas du Sud Ouest moved forward with the Artere du Midi consisting of a 375-kilometer gas pipeline, respectively in charge of 200-kilometer and a 175-kilometer sections linking the east and west grids in the southeast of France. A significant part of the Artere du Midi included a crossing of the Rhone River near Aries. The Rhone flows from north to south between the volcanic massif central and the Alps into the Mediterranean Sea.more » The crossing site is just at the entry of the Rhone delta, where the flow decelerates and erosion deposits of large granular size have occurred for millennia. Geotechnical investigations indicated that the crossing has difficult soil conditions, mostly made of coarse sand with numerous lenses of gravel and cobble. The Rhone delta, once occupied by the Romans is scenic and historic, so the construction method was very sensitive to the local public and tourist. Despite the geotechnical conditions, Gaz de France chose the horizontal directional drilling method for construction because it offers minimal environmental impact and a relatively short construction schedule. The paper discusses the horizontal directional drilling process.« less
Spatiotemporal Responses of Groundwater Flow and Aquifer-River Exchanges to Flood Events

NASA Astrophysics Data System (ADS)

Liang, Xiuyu; Zhan, Hongbin; Schilling, Keith

2018-03-01

Rapidly rising river stages induced by flood events lead to considerable river water infiltration into aquifers and carry surface-borne solutes into hyporheic zones which are widely recognized as an important place for the biogeochemical activity. Existing studies for surface-groundwater exchanges induced by flood events usually limit to a river-aquifer cross section that is perpendicular to river channels, and neglect groundwater flow in parallel with river channels. In this study, surface-groundwater exchanges to a flood event are investigated with specific considerations of unconfined flow in direction that is in parallel with river channels. The groundwater flow is described by a two-dimensional Boussinesq equation and the flood event is described by a diffusive-type flood wave. Analytical solutions are derived and tested using the numerical solution. The results indicate that river water infiltrates into aquifers quickly during flood events, and mostly returns to the river within a short period of time after the flood event. However, the rest river water will stay in aquifers for a long period of time. The residual river water not only flows back to rivers but also flows to downstream aquifers. The one-dimensional model of neglecting flow in the direction parallel with river channels will overestimate heads and discharge in upstream aquifers. The return flow induced by the flood event has a power law form with time and has a significant impact on the base flow recession at early times. The solution can match the observed hydraulic heads in riparian zone wells of Iowa during flood events.
Pentzien lays diagonal cross of Potomac for Columbia gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klinger, O.

1976-05-01

One of the most unusual pipeline river crossings was completed last fall by Pentzien, Inc., for Columbia LNG Corp. on the Potomac River at Bryans Road, MD, 22 miles south of Washington, DC. Part of a line delivering regasified Algerian LNG to Virginia and Pennsylvania, this crossing would have been only 7896 ft straight across the river; however, to obtaining necessary country authorization without excessively delaying the project, the line was laid diagonally 19,500 ft across the river at a cost about two-thirds more than for a straight-line crossing. The concrete-coated 36-in.-diam pipe for the project was so heavy thatmore » each transport truck could handle only a single 40-ft length at a time. Laser beams on each side of the river were used to guide both the dredging and pipelaying operations.« less
Earth Observations taken by the Expedition 18 Crew

NASA Image and Video Library

2009-01-31

ISS018-E-024949 (31 Jan. 2009) --- The All-American Canal, the largest irrigation canal in the world and a key landmark along the California-Mexico border, is featured in this image photographed by an Expedition 18 crewmember on the International Space Station. This image captures about 15 kilometers of the important infrastructure corridor just west of Yuma, AZ. The prominent dark line crossing the image is the Canal which is crossed, in this view, by Interstate Highway 8. The canal carries 740.6 cubic meters (26,155 cubic feet) of water per second from the Colorado River westward to support the intensive agriculture of California?s Imperial Valley to the northwest, and to nine cities including San Diego, CA. The canal system is the Imperial Valley?s only source of water, and allows irrigation of more than 2,000 square kilometers (500,000 acres) of agricultural fields. The Coachella Canal, one of four main branch canals, leads water north to Imperial Valley. This section of the canal requires constant maintenance. Approximately 68,000 acre-feet of water per year are lost by seepage from the All-American Canal - especially where the canal crosses the great Algodones Dune Field, a portion of which is visible extending from top to bottom in the center of the image. Additionally, dune sand is constantly blown to the southeast, and into the canal. As part of California?s Colorado River Water Use Plan, 37 kilometers (23 miles) of the canal is being lined to prevent water loss by seepage. A recently opened sector parallels the old canal (right) and new lined sectors are under construction (bright lines, center). Engineers have sited new sections of the canal to avoid the worst areas of dune-sand invasion, so that the new configuration will be significantly cheaper to maintain and operate. A new road crosses the dunes and marks the US?Mexico border as part of border fence construction efforts. The margin of the Colorado River floodplain in Mexico is just visible two kilometers south of the border (lower left corner). This floodplain is Mexico?s equivalent of the Imperial Valley in terms of its enormous irrigated agricultural production.
The Impact of Incessant Strike Actions and Industrial Disputes in Cross River University of Technology and Its Effect on Students Motivation to Learning

ERIC Educational Resources Information Center

Orok-Duke, Orok Ekpo; Sackey, Jacob; Usiabulu, Michael; Bassey, Okpa Inah

2016-01-01

The purpose of this study was to find out the impact of incessant strike actions and industrial disputes in Cross River University of Technology and its effect on students' motivation to learning. Over the years, a considerable amount of effort has been put on ground in order to run the Cross River University of Technology devoid of financial…
Numerical simulation of impurity transport in Lake Baikal during the summer period

NASA Astrophysics Data System (ADS)

Tsydenov, Bair O.

2017-11-01

The distributions of impurities obtained as a result of numerical modeling on the Srednyaya arm (Selenga River mouth)- Cape Golyi cross-section of Lake Baikal, Siberia, Russia, are presented. The data on the air temperature, relative humidity, atmospheric pressure, humidity, and cloudiness from the Babushkin meteorological station from 01.06.2016 to 30.06.2016 are used as the weather condition in the mathematical model. The results of simulation have shown that the impurities dissolved in water reach the bottom of the Selenga shallow basin of Lake Baikal. As the heat accumulation increases and the river waters warm up, the maximum concentrations of suspended substances tend to remain in the upper layers of the lake.
Potential use of geothermal resources in the Snake River Basin: an environmental overview. Volume II. Annotated bibliography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spencer, S.G.; Russell, B.F.; Sullivan, J.F.

This volume is a partially annotated bibliography of reference materials pertaining to the seven KGRA's. The bibliography is divided into sections by program element as follows: terrestrial ecology, aquatic ecology, heritage resources, socioeconomics and demography, geology, geothermal, soils, hydrology and water quality, seismicity, and subsidence. Cross-referencing is available for those references which are applicable to specific KGRA's. (MHR)
22. Photographic copy of ink on linen drawing (at the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. Photographic copy of ink on linen drawing (at the archives of Niagara Mohawk Power Corporation, 300 Eric Boulevard West, Syracuse, New York 13202), Strand, Draftsman, September 23, 1913. Sheet 1-258, International Paper Company and Finch, Pruyn & Company. Concrete dam. Detail showing cross sections through the dam. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY
Scale Factor Study for 1:30 Local Scour Model

DTIC Science & Technology

2016-08-01

railway crossing on the Santa Ana River near Corona , CA. Data from the scale factor study provide an adjustment for applying documented scour...upstream and downstream of the test section respectively. Discharge into the model came from three recirculation pumps with a total capacity of ERDC...upstream baffle blocks. The total discharge was measured by reading the differential from a manometer across a venturi meter and verified with a total
Use of airborne near-infrared LiDAR for determining channel cross-section characteristics and monitoring aquatic habitat in Pacific Northwest rivers: A preliminary analysis [Chapter 6

Treesearch

Russell N. Faux; John M. Buffington; M. German Whitley; Steve H. Lanigan; Brett B. Roper

2009-01-01

Aquatic habitat monitoring is being conducted by numerous organizations in many parts of the Pacific Northwest to document physical and biological conditions of stream reaches as part of legal- and policy-mandated environmental assessments. Remote sensing using discrete-return, near-infrared, airborne LiDAR (Light Detection and Ranging) and high-resolution digital...
Debris flows from tributaries of the Colorado River, Grand Canyon National Park, Arizona

USGS Publications Warehouse

Webb, Robert H.; Pringle, Patrick T.; Rink, Glenn R.

1989-01-01

A reconnaissance of 36 tributaries of the Colorado River indicates that debris flows are a major process by which sediment is transported to the Colorado River in Grand Canyon National Park. Debris flows are slurries of sediment and water that have a water content of less than about 40 percent by volume. Debris flows occur frequently in arid and semiarid regions. Slope failures commonly trigger debris flows, which can originate from any rock formation in the Grand Canyon. The largest and most frequent flows originate from the Permian Hermit Shale, the underlying Esplanade Sandstone of the Supai Group, and other formations of the Permian and Pennsylvanian Supai Group. Debris flows also occur in the Cambrian Muav Limestone and underlying Bright Angel Shale and the Quaternary basalts in the western Grand Canyon. Debris-flow frequency and magnitude were studied in detail in the Lava-Chuar Creek drainage at Colorado River mile 65.5; in the Monument Creek drainage at mile 93.5; and in the Crystal Creek drainage at mile 98.2. Debris flows have reached the Colorado River on an average of once every 20 to 30 years in the Lava-Chuar Creek drainage since about 1916. Two debris flows have reached the Colorado River in the last 25 years in Monument Creek. The Crystal Creek drainage has had an average of one debris flow reaching the Colorado River every 50 years, although the debris flow of 1966 has been the only flow that reached the Colorado River since 1900. Debris flows may actually reach the Colorado River more frequently in these drainages because evidence for all debris flows may not have been preserved in the channel-margin stratigraphy. Discharges were estimated for the peak flow of three debris flows that reached the Colorado River. The debris flow of 1966 in the Lava-Chuar Creek drainage had an estimated discharge of 4,000 cubic feet per second. The debris flow of 1984 in the Monument Creek drainage had a discharge estimated between 3,600 and 4,200 cubic feet per second. The debris flow of 1966 in the Crystal Creek drainage had a discharge estimated between 9,200 and 14,000 cubic feet per second. Determination of the effective cross-sectional area was a problem in all calculations involving superelevations on bends because areas near superelevation marks were 1.5 to 3.5 times larger than areas of upstream or downstream cross sections. Debris flows in the Grand Canyon generally are composed of 10 to 40 percent sand by weight and may represent a significant source of beach-building sand along the Colorado River. The particle-size distributions are very poorly sorted and the largest transported boulders were in the Crystal Creek drainage. The large boulders transported into the Colorado River by debris flows create or change hydraulic controls (rapids); these controls appear to be governed by the magnitude and frequency of tributary-flow events and the history of discharges on the Colorado River. Reworking of debris fans by the Colorado River creates debris bars that constrain the size of eddy systems and forms secondary rapids and riffles below tributary mouths.
Northeastern Florida Bay estuarine creek data, water years 1996-2000

USGS Publications Warehouse

Hittle, Clinton D.; Zucker, Mark A.

2004-01-01

From October 1995 to September 2000 (water years 1996-2000), continuous 15-minute stage, water velocity, salinity, and water temperature data were collected at seven estuarine creeks that flow into northeastern Florida Bay. These creeks include West Highway Creek, Stillwater Creek, Trout Creek, Mud Creek, Taylor River, Upstream Taylor River, and McCormick Creek. Discharge was computed at 15-minute intervals using mean water velocity and the cross-sectional area of the channel. Fifteen-minute unit values are presented for comparison of the quantity, quality, timing, and distribution of flows through the creeks. Revised discharge estimation formulas are presented for three noninstrumented sites (East Highway Creek, Oregon Creek and Stillwater Creek) that utilize an improved West Highway discharge rating. Stillwater Creek and Upstream Taylor River were originally noninstrumented sites; both were fully instrumented in 1999. Discharge rating equations are presented for these sites and were developed using a simple linear regression.
Digital Elevation Model Correction for the thalweg values of Obion River system, TN

NASA Astrophysics Data System (ADS)

Dullo, T. T.; Bhuyian, M. N. M.; Hawkins, S. A.; Kalyanapu, A. J.

2016-12-01

Obion River system is located in North-West Tennessee and discharges into the Mississippi River. To facilitate US Department of Agriculture (USDA) to estimate water availability for agricultural consumption a one-dimensional HEC-RAS model has been proposed. The model incorporates the major tributaries (north and south), main stem of Obion River along with a segment of the Mississippi River. A one-meter spatial resolution Light Detection and Ranging (LiDAR) derived Digital Elevation Model (DEM) was used as the primary source of topographic data. LiDAR provides fine-resolution terrain data over given extent. However, it lacks in accurate representation of river bathymetry due to limited penetration beyond a certain water depth. This reduces the conveyance along river channel as represented by the DEM and affects the hydrodynamic modeling performance. This research focused on proposing a method to overcome this issue and test the qualitative improvement by the proposed method over an existing technique. Therefore, objective of this research is to compare effectiveness of a HEC-RAS based bathymetry optimization method with an existing hydraulic based DEM correction technique (Bhuyian et al., 2014) for Obion River system in Tennessee. Accuracy of hydrodynamic simulations (upon employing bathymetry from respective sources) would be regarded as the indicator of performance. The aforementioned river system includes nine major reaches with a total river length of 310 km. The bathymetry of the river was represented via 315 cross sections equally spaced at about one km. This study targeted to selecting best practice for treating LiDAR based terrain data over complex river system at a sub-watershed scale.
Calibration and validation of a two-dimensional hydrodynamic model of the Ohio River, Jefferson County, Kentucky

USGS Publications Warehouse

Wagner, C.R.; Mueller, D.S.

2001-01-01

The quantification of current patterns is an essential component of a Water Quality Analysis Simulation Program (WASP) application in a riverine environment. The U.S. Geological Survey (USGS) provided a field validated two-dimensional Resource Management Associates-2 (RMA-2) hydrodynamic model capable of quantifying the steady-flowpatterns in the Ohio River extending from river mile 590 to 630 for the Ohio River Valley Water Sanitation Commission (ORSANCO) water-quality modeling efforts on that reach. Because of the hydrodynamic complexities induced by McAlpine Locks and Dam (Ohio River mile 607), the model was split into two segments: an upstream reach, which extended from the dam upstream to the upper terminus of the study reach at Ohio River mile 590; and a downstream reach, which extended from the dam downstream to a lower terminus at Ohio River mile 636. The model was calibrated to a low-flow hydraulic survey (approximately 35,000 cubic feet per second (ft3/s)) and verified with data collected during a high-flow survey (approximately 390,000 ft3/s). The model calibration and validation process included matching water-surface elevations at 10 locations and velocity profiles at 30 cross sections throughout the study reach. Based on the calibration and validation results, the model is a representative simulation of the Ohio River steady-flow patterns below discharges of approximately 400,000 ft3/s.
Comparison of Heat and Bromide as Ground Water Tracers Near Streams

USGS Publications Warehouse

Constantz, J.; Cox, M.H.; Su, G.W.

2003-01-01

Heat and bromide were compared as tracers for examining stream/ground water exchanges along the middle reaches of the Santa Clara River, California, during a 10-hour surface water sodium bromide injection test. Three cross sections that comprise six shallow (<1 m) piezometers were installed at the upper, middle, and lower sections of a 17 km long study reach, to monitor temperatures and bromide concentrations in the shallow ground water beneath the stream. A heat and ground water transport simulation model and a closely related solute and ground water transport simulation model were matched up for comparison of simulated and observed temperatures and bromide concentrations in the streambed. Vertical, one-dimensional simulations of sediment temperature were fitted to observed temperature results, to yield apparent streambed hydraulic conductivities in each cross section. The temperature-based hydraulic conductivities were assigned to a solute and ground water transport model to predict sediment bromide concentrations, during the sodium bromide injection test. Vertical, one-dimensional simulations of bromide concentrations in the sediments yielded a good match to the observed bromide concentrations, without adjustment of any model parameters except solute dispersivities. This indicates that, for the spatial and temporal scales examined on the Santa Clara River, the use of heat and bromide as tracers provide comparable information with respect to apparent hydraulic conductivities and fluxes for sediments near streams. In other settings, caution should be used due to differences in the nature of conservative (bromide) versus nonconservative (heat) tracers, particularly when preferential flowpaths are present.

4. ENVIRONMENT, FROM NORTH, SHOWING RIVER ROAD BRIDGE CARRYING CASSELMAN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. ENVIRONMENT, FROM NORTH, SHOWING RIVER ROAD BRIDGE CARRYING CASSELMAN RIVER ROAD OVER CASSELMAN RIVER, WITH MARYLAND GEOLOGICAL SURVEY STREAM-GAUGING STATION AT NORTHEAST CORNER OF BRIDGE - River Road Bridge, Crossing Casselman River on Casselman River Road, Grantsville, Garrett County, MD
HIV prevalence and risk behaviours among men having sex with men in Nigeria.

PubMed

Merrigan, Mike; Azeez, Aderemi; Afolabi, Bamgboye; Chabikuli, Otto Nzapfurundi; Onyekwena, Obinna; Eluwa, George; Aiyenigba, Bolatito; Kawu, Issa; Ogungbemi, Kayode; Hamelmann, Christoph

2011-02-01

To evaluate HIV and syphilis prevalence among men who have sex with men (MSM) in Nigeria, and assess their HIV-related risk behaviours and exposure to HIV prevention interventions. Cross-sectional study using respondent-driven sampling conducted in Lagos, Kano and Cross River states, Nigeria, between July and September 2007. A total of 879 MSM participated, 293 from each state. Eight participants (1.1%, CI 0.1% to 2.2%) in Cross River, 27 (9.3%, CI 5.7% to 15.4%) in Kano and 74 (17.4%, CI 12.3% to 23.2%) in Lagos tested positive for HIV. No syphilis was detected. The median age was 22 years. MSM reported an average of 4.2 male anal sex partners in the past 6 months. Between 24.4% (Lagos) and 36.0% (Kano) of MSM reported selling sex to other men. Up to 49.7% of MSM reported sex with a girlfriend and ≤ 6.5% purchased sex from female sex workers. Consistent condom use in commercial sex with other men over the past 6 months ranged from 28.0% (Cross River) to 34.3% (Kano), in contrast to between 23.9% (Kano) and 45.8% (Lagos) for non-commercial sex. Associations with HIV positivity included age in the three states, having been the receptive partner in anal sex in the past 6 months in Lagos and in Lagos and Kano feeling at risk of HIV. Large differentials in HIV prevalence between states together with high mobility, inconsistent condom use and behavioural links with female sex partners, have the potential for further HIV transmission within MSM networks, and between MSM and the general population.
Channel adjustments to historical disturbances along the lower Brazos and Sabine Rivers, south-central USA

NASA Astrophysics Data System (ADS)

Heitmuller, Franklin T.

2014-01-01

Historical channel adjustments are documented and discussed in context with anthropogenic disturbances along two meandering, coastal plain rivers - the lower Brazos and Sabine Rivers in the south-central United States. Hard-copy streamflow-measurement notes of the U.S. Geological Survey were utilized to render historical cross sections (1925-2007) at nine gauging stations, which were complemented with repeat photographs and flood-frequency analysis to assess trajectories of channel change and interpret causative mechanisms. Downstream- and upstream-propagating disturbances caused episodes of channel-bed incision and aggradation at different locations for distinct time periods along both rivers. Incision associated with upstream dams is detected, but channels are compensated downstream with sediment inputs from lateral channel migration and tributaries. In one case, temporary aggradation along the Brazos River at Waco was likely caused by a combination of dam construction and regional soil erosion. Channel-bed incision on the lowermost Brazos River is unrelated to dams, but is associated with instream aggregate extraction, possibly in conjunction with downstream channelization. On the Sabine River, extensive aggradation during the 1930s might be associated with logging activities (1880s-1930s), but whether the cause is pervasive regional-scale hillslope erosion or local-scale mill-site activities is indeterminate. Following passage of this sediment, the river generally recovered to pre-disturbance conditions and has exhibited stability despite a mainstem reservoir. Translation of this sediment slug is attenuated by a transition to a flood-prone, distributary-dominated system downstream of the Holocene-Pleistocene terrace onlap position. Additional findings include cross-channel hingepoints separating thalweg incision from simultaneous point-bar or bank accretion at meander bends, which indicates channel adjustment occurs along non-cohesive beds in preference to cohesive or artificially reinforced banks. Also, flood reduction has resulted in bankfull stages that are higher than levels associated with the post-regulation 2-year return period. Finally, vegetation encroachment along banks since the 1970s coupled with reduced flooding along the lower Brazos River has promoted bank accretion deposits that, when fully developed, serve as morphologic indicators of the post-regulation 1- to 2-year return period stage.
The Northern end of the Dead Sea Basin: Geometry from reflection seismic evidence

USGS Publications Warehouse

Al-Zoubi, A. S.; Heinrichs, T.; Qabbani, I.; ten Brink, Uri S.

2007-01-01

Recently released reflection seismic lines from the Eastern side of the Jordan River north of the Dead Sea were interpreted by using borehole data and incorporated with the previously published seismic lines of the eastern side of the Jordan River. For the first time, the lines from the eastern side of the Jordan River were combined with the published reflection seismic lines from the western side of the Jordan River. In the complete cross sections, the inner deep basin is strongly asymmetric toward the Jericho Fault supporting the interpretation of this segment of the fault as the long-lived and presently active part of the Dead Sea Transform. There is no indication for a shift of the depocenter toward a hypothetical eastern major fault with time, as recently suggested. Rather, the north-eastern margin of the deep basin takes the form of a large flexure, modestly faulted. In the N-S-section along its depocenter, the floor of the basin at its northern end appears to deepen continuously by roughly 0.5??km over 10??km distance, without evidence of a transverse fault. The asymmetric and gently-dipping shape of the basin can be explained by models in which the basin is located outside the area of overlap between en-echelon strike-slip faults. ?? 2007 Elsevier B.V. All rights reserved.
Tracing of the Rhône River within Lake Geneva using stable isotope composition of water

NASA Astrophysics Data System (ADS)

Cotte, Gabriel; Vennemann, Torsten

2017-04-01

Determining the hydrodynamics of lake water is essential for a better understanding of nutrient transport but also of the distribution of potential pollutants through water reservoirs. The objective of this study is to understand the mixing of Rhône River water within Lake Geneva. During summer and autumn, when the lake thermally well stratified, the Rhône River water can potentially flow more or less directly towards and finally out of the "Petit Lac" (small lake basin close to Geneva) more than 55 km from its mouth. During winter, when stratification is weakened, the water from the Rhône River mixes more diffusively with the water of Lake Geneva. The aim of this study is to determine the path of the Rhône River through the lake more precisely and identify the thermal and meteorologic conditions favourable for different types of flows as suggested by physical circulation models of the Rhône River interflows. Waters are sampled from different North-South transects across the lake. Bathymetric profiles are measured for temperature, pH, conductivity and oxygen concentrations. In addition, the H- and O-isotope compositions of water, the C-isotope composition of dissolved inorganic carbon and the major ions are analysed. Sampling campaigns are carried out every two months to study the hydrodynamics of the lake at varying thermal conditions. The isotopic composition of water was already proven to be a powerful tool to trace the Rhône River interflow within the lake (Halder et al., 2013) but the details of this interflow remain debatable. It is the aim of the present study to use the isotopic tracer method in much more detailed cross-sections as a tool to both test and verify interflow models based on wind patterns and thermal dispersion of the waters. The chosen cross-sections, to be sampled regularly and "event-based", that is after extended periods of similar meteorological conditions, should allow for more precise estimates of the path of the Rhône water interflow and the control of different wind conditions on the formation of resultant gyres of circulation within Lake Geneva. For example, an anticlockwise gyre forces Rhône River water to flow at intermediate depths towards the northern shore of the lake and a return interflow close to the southern shore of the lake. Isotopic mixing models coupled to physical hydrodynamic models of the lake will help constrain the flow paths of the Rhône. References Halder J., Decrouy L. & Vennemann T. 2013 : Mixing of Rhône River water in Lake Geneva (Switzerland-France) inferred from stable hydrogen and oxygen isotope profiles, Journal of Hydrology 477:152-164
Intimate Views of Cretaceous Plutons, the Colorado River Extensional Corridor, and Colorado River Stratigraphy in and near Topock Gorge, Southwest USA

NASA Astrophysics Data System (ADS)

Howard, K. A.; John, B. E.; Nielson, J. E.; Miller, J. M.; Priest, S. S.

2010-12-01

Geologic mapping of the Topock 7.5’ quadrangle, CA-AZ, reveals a structurally complex part of the Colorado River extensional corridor, and a younger stratigraphic record of landscape evolution during the history of the Colorado River. Paleoproterozoic gneisses and Mesoproterozoic granitoids and diabase sheets are exposed through cross-sectional thicknesses of many kilometers. Mesozoic to Tertary igneous rocks intrude the older rocks and include dismembered parts of the Late Cretaceous Chemehuevi Mountains Plutonic Suite. Plutons of this suite exposed in the Arizona part of the quad reconstruct, if Miocene deformation is restored, as cupolas capping the sill-like Chemehuevi Mountains batholith exposed in California. A nonconformity between Proterozoic and Miocene rocks reflects pre-Miocene uplift and erosional stripping of regional Paleozoic and Mesozoic strata. Thick (1-3 km) Miocene sections of volcanic rocks, sedimentary breccias, and conglomerate record the Colorado River extensional corridor’s structural and erosional evolution. Four major Miocene low-angle normal faults and a steep block-bounding Miocene fault divide the deformed rocks into major structural plates and giant tilted blocks on the east side of the Chemehuevi Mountains core complex. The low-angle faults attenuate >10 km of crustal section, superposing supracrustal and upper crustal rocks against originally deeper gneisses and granitoids. The block-bounding Gold Dome fault zone juxtaposes two large hanging-wall blocks, each tilted 90°, and splays at its tip into folds that deform layered Miocene rocks. A 15-16 Ma synfaulting intrusion occupies the triangular zone or gap where the folding strata detached from an inside corner along this fault between the tilt blocks. Post-extensional landscape evolution is recorded by upper Miocene to Quaternary strata, locally deformed. This includes several Pliocene and younger aggradational episodes in the Colorado River valley, and intervening degradation episodes at times when the river re-incised. Post-Miocene aggradational sequences include (1) the Bouse Formation, (2) fluvial deposits correlated with the alluvium of Bullhead City, (3) a younger fluvial boulder conglomerate, (4) the Chemehuevi Formation and related valley-margin deposits, and (5) and Holocene deposits under the valley floor.
Long-term continuous acoustical suspended-sediment measurements in rivers - Theory, application, bias, and error

USGS Publications Warehouse

Topping, David J.; Wright, Scott A.

2016-05-04

It is commonly recognized that suspended-sediment concentrations in rivers can change rapidly in time and independently of water discharge during important sediment‑transporting events (for example, during floods); thus, suspended-sediment measurements at closely spaced time intervals are necessary to characterize suspended‑sediment loads. Because the manual collection of sufficient numbers of suspended-sediment samples required to characterize this variability is often time and cost prohibitive, several “surrogate” techniques have been developed for in situ measurements of properties related to suspended-sediment characteristics (for example, turbidity, laser-diffraction, acoustics). Herein, we present a new physically based method for the simultaneous measurement of suspended-silt-and-clay concentration, suspended-sand concentration, and suspended‑sand median grain size in rivers, using multi‑frequency arrays of single-frequency side‑looking acoustic-Doppler profilers. The method is strongly grounded in the extensive scientific literature on the incoherent scattering of sound by random suspensions of small particles. In particular, the method takes advantage of theory that relates acoustic frequency, acoustic attenuation, acoustic backscatter, suspended-sediment concentration, and suspended-sediment grain-size distribution. We develop the theory and methods, and demonstrate the application of the method at six study sites on the Colorado River and Rio Grande, where large numbers of suspended-sediment samples have been collected concurrently with acoustic attenuation and backscatter measurements over many years. The method produces acoustical measurements of suspended-silt-and-clay and suspended-sand concentration (in units of mg/L), and acoustical measurements of suspended-sand median grain size (in units of mm) that are generally in good to excellent agreement with concurrent physical measurements of these quantities in the river cross sections at these sites. In addition, detailed, step-by-step procedures are presented for the general river application of the method.Quantification of errors in sediment-transport measurements made using this acoustical method is essential if the measurements are to be used effectively, for example, to evaluate uncertainty in long-term sediment loads and budgets. Several types of error analyses are presented to evaluate (1) the stability of acoustical calibrations over time, (2) the effect of neglecting backscatter from silt and clay, (3) the bias arising from changes in sand grain size, (4) the time-varying error in the method, and (5) the influence of nonrandom processes on error. Results indicate that (1) acoustical calibrations can be stable for long durations (multiple years), (2) neglecting backscatter from silt and clay can result in unacceptably high bias, (3) two frequencies are likely required to obtain sand-concentration measurements that are unbiased by changes in grain size, depending on site-specific conditions and acoustic frequency, (4) relative errors in silt-and-clay- and sand-concentration measurements decrease substantially as concentration increases, and (5) nonrandom errors may arise from slow changes in the spatial structure of suspended sediment that affect the relations between concentration in the acoustically ensonified part of the cross section and concentration in the entire river cross section. Taken together, the error analyses indicate that the two-frequency method produces unbiased measurements of suspended-silt-and-clay and sand concentration, with errors that are similar to, or larger than, those associated with conventional sampling methods.
The Irrigation Effect: How River Regulation Can Promote Some Riparian Vegetation.

PubMed

Gill, Karen M; Goater, Lori A; Braatne, Jeffrey H; Rood, Stewart B

2018-04-01

River regulation impacts riparian ecosystems by altering the hydrogeomorphic conditions that support streamside vegetation. Obligate riparian plants are often negatively impacted since they are ecological specialists with particular instream flow requirements. Conversely, facultative riparian plants are generalists and may be less vulnerable to river regulation, and could benefit from augmented flows that reduce drought stress during hot and dry periods. To consider this 'irrigation effect' we studied the facultative shrub, netleaf hackberry (Celtis reticulata), the predominant riparian plant along the Hells Canyon corridor of the Snake River, Idaho, USA, where dams produce hydropeaking, diurnal flow variation. Inventories of 235 cross-sectional transects revealed that hackberry was uncommon upstream from the reservoirs, sparse along the reservoir with seasonal draw-down and common along two reservoirs with stabilized water levels. Along the Snake River downstream, hackberry occurred in fairly continuous, dense bands along the high water line. In contrast, hackberry was sparsely scattered along the free-flowing Salmon River, where sandbar willow (Salix exigua), an obligate riparian shrub, was abundant. Below the confluence of the Snake and Salmon rivers, the abundance and distribution of hackberry were intermediate between the two upstream reaches. Thus, river regulation apparently benefited hackberry along the Snake River through Hells Canyon, probably due to diurnal pulsing that wets the riparian margin. We predict similar benefits for some other facultative riparian plants along other regulated rivers with hydropeaking during warm and dry intervals. To analyze the ecological impacts of hydropeaking we recommend assessing daily maxima, as well as daily mean river flows.
The Irrigation Effect: How River Regulation Can Promote Some Riparian Vegetation

NASA Astrophysics Data System (ADS)

Gill, Karen M.; Goater, Lori A.; Braatne, Jeffrey H.; Rood, Stewart B.

2018-04-01

River regulation impacts riparian ecosystems by altering the hydrogeomorphic conditions that support streamside vegetation. Obligate riparian plants are often negatively impacted since they are ecological specialists with particular instream flow requirements. Conversely, facultative riparian plants are generalists and may be less vulnerable to river regulation, and could benefit from augmented flows that reduce drought stress during hot and dry periods. To consider this `irrigation effect' we studied the facultative shrub, netleaf hackberry ( Celtis reticulata), the predominant riparian plant along the Hells Canyon corridor of the Snake River, Idaho, USA, where dams produce hydropeaking, diurnal flow variation. Inventories of 235 cross-sectional transects revealed that hackberry was uncommon upstream from the reservoirs, sparse along the reservoir with seasonal draw-down and common along two reservoirs with stabilized water levels. Along the Snake River downstream, hackberry occurred in fairly continuous, dense bands along the high water line. In contrast, hackberry was sparsely scattered along the free-flowing Salmon River, where sandbar willow ( Salix exigua), an obligate riparian shrub, was abundant. Below the confluence of the Snake and Salmon rivers, the abundance and distribution of hackberry were intermediate between the two upstream reaches. Thus, river regulation apparently benefited hackberry along the Snake River through Hells Canyon, probably due to diurnal pulsing that wets the riparian margin. We predict similar benefits for some other facultative riparian plants along other regulated rivers with hydropeaking during warm and dry intervals. To analyze the ecological impacts of hydropeaking we recommend assessing daily maxima, as well as daily mean river flows.
PIT-tagged particle study of bed mobility in a Maine salmon river impacted by logging activities

NASA Astrophysics Data System (ADS)

Thompson, D. M.; Fixler, S. A.; Roberts, K. E.; McKenna, M.; Marshall, A. E.; Koenig, S.

2017-12-01

Presenting an interim report on a study on the Narraguagus River in Maine, which utilizes laser total stations cross-sectional surveys and tracking of passive integrated transponder (PIT) tags embedded in glass spheres to document changes in channel-bed characteristics associated with large wood (LW) additions and natural spawning activities. In 2016, work was initiated to monitor changes in bed elevation and sediment mobility with the addition of LW to the Narraguagus River as part of a restoration effort. Ten cross-sections, spaced 5-m apart, were established and surveyed with a laser total station in each of three different study reaches. The study sites include a control reach, a section with anticipated spawning activities and a site with ongoing LW placement. A grid of 200 glass spheres embedded with PIT tags, with twenty alternating 25-mm and 40-mm size particles equally spaced along each of the ten transects, were placed to serve as point sensors to detect sediment mobilization within each reach. In 2017, the site was revisited to determine if differences in PIT-tagged tracer particle mobilization reflect locations were LW was added and places where Atlantic salmon (Salmo salar) and sea lamprey (Petromyzon marinus) construct spawning redds. The positions of PIT-tagged tracer particles was recorded, but particles were not disturbed or uncovered to permit study of potential reworking of buried tracer particles the following year. Full tracer particle recovery will be determined in 2018 to determine if depths of tracer burial and changes in bed elevation vary among places near redds, LW and main channel locations. The data will be used to determine if salmon redds are preferentially located in either places with greater evidence of sediment reworking or alternatively in stable areas? The study will help determine the degree of bed disruption associated with spawning activities and whether LW placement encourages similar sediment mobilization processes.
Situk River Hydrology Following Closure of Russell Fiord by Hubbard Glacier

DTIC Science & Technology

2011-03-01

and in- vestigate potential channel erosion, the impacts on the Old Situk River crossing and Situk Lake, and the potential influence of log jams and...52 Log jams ...crossing and Situk Lake (the upstream source of the Situk River), and the potential impacts of log jams and channel migration. ERDC/CRREL TR-11-5 4 2
Feasibility of estimate sediment yield in the non-sediment monitoring station area - A case study of Alishan River watershed,Taiwan

NASA Astrophysics Data System (ADS)

Chang, ChiaChi; Chan, HsunChuan; Jia, YaFei; Zhang, YaoXin

2017-04-01

Due to the steep topography, frail geology and concentrated rainfall in wet season, slope disaster occurred frequently in Taiwan. In addition, heavy rainfall induced landslides in upper watersheds. The sediment yield on the slopeland affects the sediment transport in the river. Sediment deposits on the river bed reduce the river cross section and change the flow direction. Furthermore, it generates risks to residents' lives and property in the downstream. The Taiwanese government has been devoting increasing efforts on the sedimentary management issues and on reduction in disaster occurrence. However, due to the limited information on the environmental conditions in the upper stream, it is difficult to set up the sedimentary monitoring equipment. This study used the upper stream of the Qingshuei River, the Alishan River, as a study area. In August 2009, Typhoon Morakot caused the sedimentation of midstream and downstream river courses in the Alishan River. Because there is no any sediment monitoring stations within the Alishan River watershed, the sediment yield values are hard to determine. The objective of this study is to establish a method to analyze the event-landslide sediment transport in the river on the upper watershed. This study numerically investigated the sediment transport in the Alishan River by using the KINEROS 2 model developed by the United States Department of Agriculture and the CCHE1D model developed by the National Center for Computational Hydroscience and Engineering. The simulated results represent the morphology changes in the Alishan River during the typhoon events. The results consist of a critical strategy reference for the sedimentary management for the Alishan River watershed.
Flood-inundation map and water-surface profiles for floods of selected recurrence intervals, Consumnes River and Deer Creek, Sacramento County, California

USGS Publications Warehouse

Guay, Joel R.; Harmon, Jerry G.; McPherson, Kelly R.

1998-01-01

The damage caused by the January 1997 floods along the Cosumnes River and Deer Creek generated new interest in planning and managing land use in the study area. The 1997 floodflow peak, the highest on record and considered to be a 150-year flood, caused levee failures at 24 locations. In order to provide a technical basis for floodplain management practices, the U.S. Goelogical Survey, in cooperation with the Federal Emergency Management Agency, completed a flood-inundation map of the Cosumnes River and Deer Creek drainage from Dillard Road bridge to State Highway 99. Flood frequency was estimated from streamflow records for the Cosumnes River at Michigan Bar and Deer Creek near Sloughhouse. Cross sections along a study reach, where the two rivers generally flow parallel to one another, were used with a step-backwater model (WSPRO) to estimate the water-surface profile for floods of selected recurrence intervals. A flood-inundation map was developed to show flood boundaries for the 100-year flood. Water-surface profiles were developed for the 5-, 10-, 50-, 100-, and 500-year floods.
Using a coupled eco-hydrodynamic model to predict habitat for target species following dam removal

USGS Publications Warehouse

Tomsic, C.A.; Granata, T.C.; Murphy, R.P.; Livchak, C.J.

2007-01-01

A habitat suitability index (HSI) model was developed for a water quality sensitive fish (Greater Redhorse) and macroinvertebrate (Plecoptera) species to determine the restoration success of the St. John Dam removal for the Sandusky River (Ohio). An ArcGIS?? model was created for pre- and post-dam removal scenarios. Inputs to the HSI model consist of substrate distributions from river surveys, and water level and velocity time series, outputs from a hydrodynamic model. The ArcGIS?? model predicted habitat suitability indices at 45 river cross-sections in the hydrodynamic model. The model was programmed to produce polygon layers, using graphical user interfaces that were displayed in the ArcGIS?? environment. The results of the model clearly show an increase of habitat suitability from pre- to post-dam removal periods and in the former reservoir. The change in suitability of the model is attributed mostly to the change in depth in the river following the dam removal for both the fish and invertebrate species. The results of the invertebrate model followed the same positive trend as species enumerations from the river basin. ?? 2007 Elsevier B.V. All rights reserved.
Continuous measurement of suspended-sediment discharge in rivers by use of optical backscatterance sensors

USGS Publications Warehouse

Schoellhamer, D.H.; Wright, S.A.; Bogen, J.; Fergus, T.; Walling, D.

2003-01-01

Optical sensors have been used to measure turbidity and suspended-sediment concentration by many marine and estuarine studies, and optical sensors can provide automated, continuous time series of suspended-sediment concentration and discharge in rivers. Three potential problems with using optical sensors are biological fouling, particle-size variability, and particle-reflectivity variability. Despite varying particle size, output from an optical backscatterance sensor in the Sacramento River at Freeport, California, USA, was calibrated successfully to discharge-weighted, cross-sectionally averaged suspended-sediment concentration, which was measured with the equal discharge-, or width-increment, methods and an isokinetic sampler. A correction for sensor drift was applied to the 3-year time series. However, the calibration of an optical backscatterance sensor used in the Colorado River at Cisco, Utah, USA, was affected by particle-size variability. The adjusted time series at Freeport was used to calculate hourly suspended-sediment discharge that compared well with daily values from a sediment station at Freeport. The appropriateness of using optical sensors in rivers should be evaluated on a site-specific basis and measurement objectives, potential particle size effects, and potential fouling should be considered.
Risk assessment for arsenic-contaminated groundwater along River Indus in Pakistan.

PubMed

Rabbani, Unaib; Mahar, Gohar; Siddique, Azhar; Fatmi, Zafar

2017-02-01

The study determined the risk zone and estimated the population at risk of adverse health effects for arsenic exposure along the bank of River Indus in Pakistan. A cross-sectional survey was conducted in 216 randomly selected villages of one of the districts along River Indus. Wells of ten households from each village were selected to measure arsenic levels. The location of wells was identified using global positioning system device, and spatial variations of the groundwater contamination were assessed using geographical information system tools. Using layers of contaminated drinking water wells according to arsenic levels and population with major landmarks, a risk zone and estimated population at risk were determined, which were exposed to arsenic level ≥10 µg/L. Drinking wells with arsenic levels of ≥10 µg/L were concentrated within 18 km near the river bank. Based on these estimates, a total of 13 million people were exposed to ≥10 µg/L arsenic concentration along the course of River Indus traversing through 27 districts in Pakistan. This information would help the researchers in designing health effect studies on arsenic and policy makers in allocating resources for designing focused interventions for arsenic mitigation in Pakistan. The study methods have implication on similar populations which are affected along rivers due to arsenic contamination.
Evaluation of models and data for assessing whooping crane habitat in the central Platte River, Nebraska

USGS Publications Warehouse

Farmer, Adrian H.; Cade, Brian S.; Terrell, James W.; Henriksen, Jim H.; Runge, Jeffery T.

2005-01-01

The primary objectives of this evaluation were to improve the performance of the Whooping Crane Habitat Suitability model (C4R) used by the U.S. Fish and Wildlife Service (Service) for defining the relationship between river discharge and habitat availability, and to assist the Service in implementing improved model(s) with existing hydraulic files. The C4R habitat model is applied at the scale of individual river cross-sections, but the model outputs are scaledup to larger reaches of the river using a decision support “model” comprised of other data and procedures. Hence, the validity of the habitat model depends at least partially on how its outputs are incorporated into this larger context. For that reason, we also evaluated other procedures including the PHABSIM data files, the FORTRAN computer programs used to implement the model, and other parameters used to simulate the relationship between river flows and the availability of Whooping Crane roosting habitat along more than 100 miles of heterogeneous river channels. An equally important objective of this report was to fully document these related procedures as well as the model and evaluation results so that interested parties could readily understand the technical basis for the Service’s recommendations.
Studying the Permian Cross-section (Volga Region) Using Chemical and Isotopic Investigations

NASA Astrophysics Data System (ADS)

Gareev, B. I.; Batalin, G. A.; Nurgalieva, N. G.; Nourgaliev, D. K.

2016-12-01

This paper presents a study of international important site: the cross-section of Permian system's Urzhumian Stagein the ravine "Pechischy". Outcrop is located on the right bank of the Volga River (about 10 km West of Kazan). Ithas local, regional and planetary correlation features and also footprints of different geographical scale events.The main objective in the research is the deep study of sediments using chemical and isotopic investigations. XRFspectrometer was used for chemical investigations of samples. Chemistry of carbonates and clastic rocks includesthe analysis of chemical elements, compounds, petrochemical (lithogeochemical) modules for the interpretationof the genesis of lithotypes. For the review of the geochemistry of stable isotopes of carbon (oxygen) we usedIRMS. The main objective is the nature of the isotope fractionation issues, to addressing the issues of stratigraphyand paleogeography.The measurements have shown the variability of chemical parameters in cross-section. It gives us opportunity tosee small changes in sedimentation and recognize the factors that influence to the process.The work was carried out according to the Russian Government's Program of Competitive Growth of KazanFederal University, supported by the grant provided to the Kazan State University for performing the state programin the field of scientific research.
Denitrification potential of riparian soils in relation to multiscale spatial environmental factors: a case study of a typical watershed, China.

PubMed

Wei, Jianbing; Feng, Hao; Cheng, Quanguo; Gao, Shiqian; Liu, Haiyan

2017-02-01

The objective of this study was to test the hypothesis that environmental regulators of riparian zone soil denitrification potential differ according to spatial scale within a watershed; consequently, a second objective was to provide spatial strategies for conserving and restoring the purification function of runoff in riparian ecosystems. The results show that soil denitrification in riparian zones was more heterogeneous at the profile scale than at the cross-section and landscape scales. At the profile scale, biogeochemical factors (including soil total organic carbon, total nitrogen, and nitrate-nitrogen) were the major direct regulators of the spatial distribution of soil denitrification enzyme activity (DEA). At the cross-section scale, factors included distance from river bank and vegetation density, while landscape-scale factors, including topographic index, elevation, and land use types, indirectly regulated the spatial distribution of DEA. At the profile scale, soil DEA was greatest in the upper soil layers. At the cross-section scale, maximum soil DEA occurred in the mid-part of the riparian zone. At the landscape scale, soil DEA showed an increasing trend towards downstream sites, except for those in urbanized areas.
S-wave refraction survey of alluvial aggregate

USGS Publications Warehouse

Ellefsen, Karl J.; Tuttle, Gary J.; Williams, Jackie M.; Lucius, Jeffrey E.

2005-01-01

An S-wave refraction survey was conducted in the Yampa River valley near Steamboat Springs, Colo., to determine how well this method could map alluvium, a major source of construction aggregate. At the field site, about 1 m of soil overlaid 8 m of alluvium that, in turn, overlaid sedimentary bedrock. The traveltimes of the direct and refracted S-waves were used to construct velocity cross sections whose various regions were directly related to the soil, alluvium, and bed-rock. The cross sections were constrained to match geologic logs that were developed from drill-hole data. This constraint minimized the ambiguity in estimates of the thickness and the velocity of the alluvium, an ambiguity that is inherent to the S-wave refraction method. In the cross sections, the estimated S-wave velocity of the alluvium changed in the horizontal direction, and these changes were attributed to changes in composition of the alluvium. The estimated S-wave velocity of the alluvium was practically constant in the vertical direc-tion, indicating that the fine layering observed in the geologic logs could not be detected. The S-wave refraction survey, in conjunction with independent information such as geologic logs, was found to be suitable for mapping the thickness of the alluvium.

Identifiability of altimetry-based rating curve parameters in function of river morphological parameters

NASA Astrophysics Data System (ADS)

Paris, Adrien; André Garambois, Pierre; Calmant, Stéphane; Paiva, Rodrigo; Walter, Collischonn; Santos da Silva, Joecila; Medeiros Moreira, Daniel; Bonnet, Marie-Paule; Seyler, Frédérique; Monnier, Jérôme

2016-04-01

Estimating river discharge for ungauged river reaches from satellite measurements is not straightforward given the nonlinearity of flow behavior with respect to measurable and non measurable hydraulic parameters. As a matter of facts, current satellite datasets do not give access to key parameters such as river bed topography and roughness. A unique set of almost one thousand altimetry-based rating curves was built by fit of ENVISAT and Jason-2 water stages with discharges obtained from the MGB-IPH rainfall-runoff model in the Amazon basin. These rated discharges were successfully validated towards simulated discharges (Ens = 0.70) and in-situ discharges (Ens = 0.71) and are not mission-dependent. The rating curve writes Q = a(Z-Z0)b*sqrt(S), with Z the water surface elevation and S its slope gained from satellite altimetry, a and b power law coefficient and exponent and Z0 the river bed elevation such as Q(Z0) = 0. For several river reaches in the Amazon basin where ADCP measurements are available, the Z0 values are fairly well validated with a relative error lower than 10%. The present contribution aims at relating the identifiability and the physical meaning of a, b and Z0given various hydraulic and geomorphologic conditions. Synthetic river bathymetries sampling a wide range of rivers and inflow discharges are used to perform twin experiments. A shallow water model is run for generating synthetic satellite observations, and then rating curve parameters are determined for each river section thanks to a MCMC algorithm. Thanks to twin experiments, it is shown that rating curve formulation with water surface slope, i.e. closer from Manning equation form, improves parameter identifiability. The compensation between parameters is limited, especially for reaches with little water surface variability. Rating curve parameters are analyzed for riffle and pools for small to large rivers, different river slopes and cross section shapes. It is shown that the river bed elevation Z0is systematically well identified with relative errors on the order of a few %. Eventually, these altimetry-based rating curves provide morphological parameters of river reaches that can be used as inputs into hydraulic models and a priori information that could be useful for SWOT inversion algorithms.
77 FR 65929 - Notice of Final Federal Agency Actions on the Tappan Zee Hudson River Crossing Project in New York

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-31

... 21st Century Act (MAP-21), Pub. L. 112-141, Sec. 1308, 126 Stat. 405 (2012). Issued on: October 24... of 1966 [49 U.S.C. 303]. 4. Wildlife: Endangered Species Act [16 U.S.C. 1531-1544 and Section 1536], Marine Mammal Protection Act [16 U.S.C. 1361], Fish and Wildlife Coordination Act [16 U.S.C. 661-667(d...
Modeling Surface Water Dynamics in the Amazon Basin Using Mosart-Inundation-v1.0: Impacts of Geomorphological Parameters and River Flow Representation

NASA Technical Reports Server (NTRS)

Luo, Xiangyu; Li, Hong-Yi; Leung, Ruby; Tesfa, Teklu K.; Getirana, Augusto; Papa, Fabrice; Hess, Laura L.

2017-01-01

Surface water dynamics play an important role in water, energy and carbon cycles of the Amazon Basin. A macro-scale inundation scheme was integrated with a surface-water transport model and the extended model was applied in this vast basin. We addressed the challenges of improving basin-wide geomorphological parameters and river flow representation for 15 large-scale applications. Vegetation-caused biases embedded in the HydroSHEDS DEM data were alleviated by using a vegetation height map of about 1-km resolution and a land cover dataset of about 90-m resolution. The average elevation deduction from the DEM correction was about 13.2 m for the entire basin. Basin-wide empirical formulae for channel cross-sectional geometry were adjusted based on local information for the major portion of the basin, which could significantly reduce the cross-sectional area for the channels of some subregions. The Manning roughness coefficient of the channel 20 varied with the channel depth to reflect the general rule that the relative importance of riverbed resistance in river flow declined with the increase of river size. The entire basin was discretized into 5395 subbasins (with an average area of 1091.7 km2), which were used as computation units. The model was driven by runoff estimates of 14 years (1994 2007) generated by the ISBA land surface model. The simulated results were evaluated against in situ streamflow records, and remotely sensed Envisat altimetry data and GIEMS inundation data. The hydrographs were reproduced fairly well for the majority of 25 13 major stream gauges. For the 11 subbasins containing or close to 11 of the 13 gauges, the timing of river stage fluctuations was captured; for most of the 11 subbasins, the magnitude of river stage fluctuations was represented well. The inundation estimates were comparable to the GIEMS observations. Sensitivity analyses demonstrated that refining floodplain topography, channel morphology and Manning roughness coefficients, as well as accounting for backwater effects could evidently affect local and upstream inundation, which consequently affected flood waves and inundation of the downstream 30 area. It was also shown that the river stage was sensitive to local channel morphology and Manning roughness coefficients, as well as backwater effects. The understanding obtained in this study could be helpful to improving modeling of surface hydrology in basins with evident inundation, especially at regional or larger scales.
The Grain-size Patchiness of Braided Gravel-Bed Streams - example of the Urumqi River (northeast Tian Shan, China)

NASA Astrophysics Data System (ADS)

Guerit, L.; Barrier, L.; Narteau, C.; Métivier, F.; Liu, Y.; Lajeunesse, E.; Gayer, E.; Meunier, P.; Malverti, L.; Ye, B.

2014-02-01

In gravel-bed rivers, sediments are often sorted into patches of different grain-sizes, but in braided streams, the link between this sorting and the channel morpho-sedimentary elements is still unclear. In this study, the size of the bed sediment in the shallow braided gravel-bed Urumqi River is characterized by surface-count and volumetric sampling methods. Three morpho-sedimentary elements are identified in the active threads of the river: chutes at flow constrictions, which pass downstream to anabranches and bars at flow expansions. The surface and surface-layer grain-size distributions of these three elements show that they correspond to only two kinds of grain-size patches: (1) coarse-grained chutes, coarser than the bulk river bed, and (2) finer-grained anabranches and bars, consistent with the bulk river bed. In cross-section, the chute patches are composed of one coarse-grained top layer, which can be interpreted as a local armour layer overlying finer deposits. In contrast, the grain size of the bar-anabranch patches is finer and much more homogeneous in depth than the chute patches. Those patches, which are features of lateral and vertical sorting associated to the transport dynamics that build braided patterns, may be typical of active threads in shallow gravel-bed rivers and should be considered in future works on sorting processes and their geomorphologic and stratigraphic results.
The distribution of sediments grain size along the depth in source of the Yangtze River, Tibetan Plateau, China

NASA Astrophysics Data System (ADS)

Zhou, Y.; Yao, S.; Zhou, S.; Liu, X.; Yan, X.; Lu, J.

2017-12-01

Sediment was the one result of river process, in alluvial rive, it can reflect the hydrodynamic characteristic, even the hydrology and climate. In the source region of the Yangtze River with few human activities, The Qumalai Reach of the Tongtianhe River was selected to research the distribution of sediments grain size along the depth. The vertical drilling tools were used to obtain 7 boreholes along the river cross section, and the sedimentary cores were made analysis of stratification and granularity. The results show: The sediments are dominated by sand and grail, the sediment transport capacity of river sources is strong; the grain size frequency distribution curve with 2 3 kurtosis, main peak is sharp, it is typical deposit sediment of the suspended load; The grain size coarsen from the stream terrace to the main channel, sediment transport capacity of main stream is bigger; There are several coarse and fine sediments layers in the sedimentary core of the terrace and flood plain, medium diameters of each layer are various from 0.4mm to 80mm, different layer with different grain size can reflect the different hydrodynamic characteristic of each historical period. This result can provide the original data and enlightenment to support the research for historical river process and hydrology so much as the climate change.
Long-term continuous acoustical suspended-sediment measurements in rivers – Theory, evaluation, and results from 14 stations on five rivers

USGS Publications Warehouse

Topping, David; Wright, Scott A.; Griffiths, Ronald; Dean, David

2016-01-01

We have developed a physically based method for using two acoustic frequencies to measure suspended-silt-and-clay concentration, suspended-sand concentration, and suspended-sand median grain size in river cross sections at 15-minute intervals over decadal timescales. The method is strongly grounded in the extensive scientific literature on the scattering of sound by suspensions of small particles. In particular, the method takes advantage of the specific theoretical relations among acoustic frequency, acoustic attenuation, acoustic backscatter, suspended-sediment concentration, and suspended-sediment grain-size distribution. We briefly describe the theory and methods, demonstrate the application of the method, and compute biases and errors in the method at 14 stations in the Colorado River and Rio Grande basins, where large numbers of suspended-sediment samples have been collected concurrently with acoustical measurements over many years. Quantification of errors in sediment-transport measurements made using this method is essential if the measurements are to be used effectively, e.g., to evaluate uncertainty in long-term sediment loads and budgets
Synthetic river valleys: Creating prescribed topography for form-process inquiry and river rehabilitation design

NASA Astrophysics Data System (ADS)

Brown, R. A.; Pasternack, G. B.; Wallender, W. W.

2014-06-01

The synthesis of artificial landforms is complementary to geomorphic analysis because it affords a reflection on both the characteristics and intrinsic formative processes of real world conditions. Moreover, the applied terminus of geomorphic theory is commonly manifested in the engineering and rehabilitation of riverine landforms where the goal is to create specific processes associated with specific morphology. To date, the synthesis of river topography has been explored outside of geomorphology through artistic renderings, computer science applications, and river rehabilitation design; while within geomorphology it has been explored using morphodynamic modeling, such as one-dimensional simulation of river reach profiles, two-dimensional simulation of river networks, and three-dimensional simulation of subreach scale river morphology. To date, no approach allows geomorphologists, engineers, or river rehabilitation practitioners to create landforms of prescribed conditions. In this paper a method for creating topography of synthetic river valleys is introduced that utilizes a theoretical framework that draws from fluvial geomorphology, computer science, and geometric modeling. Such a method would be valuable to geomorphologists in understanding form-process linkages as well as to engineers and river rehabilitation practitioners in developing design surfaces that can be rapidly iterated. The method introduced herein relies on the discretization of river valley topography into geometric elements associated with overlapping and orthogonal two-dimensional planes such as the planform, profile, and cross section that are represented by mathematical functions, termed geometric element equations. Topographic surfaces can be parameterized independently or dependently using a geomorphic covariance structure between the spatial series of geometric element equations. To illustrate the approach and overall model flexibility examples are provided that are associated with mountain, lowland, and hybrid synthetic river valleys. To conclude, recommended advances such as multithread channels are discussed along with potential applications.
Anthropogenic controls on geomorphic evolution of the Upper Missouri River

NASA Astrophysics Data System (ADS)

Benthem, A.; Skalak, K.; Schenk, E.; Hupp, C.; Galloway, J.; Nustad, R.

2012-12-01

The 70-mile free flowing Upper Missouri River reach is bounded upstream by the Garrison Dam and downstream by Lake Oahe. The Garrison Dam, which regulates flow into the reach, was completed in 1953; the Oahe Dam (which created Lake Oahe and the associated delta near Bismarck, ND) was completed in 1959. This reach is used for recreation, water supply, fisheries, and as habitat for threatened and endangered species. The Upper Missouri River regularly (approximately every two years) received annual peak flows above 100,000 cubic feet per second (cfs) prior to the completion of the Garrison Dam. Annual peak flows consistently have been between 30,000 and 45,000 cfs following dam completion. The largest flood since dam regulation occurred in 2011 following an abnormally high snow pack season and a week-long rain event in the headwaters. Flood releases from the Garrison Dam began in May 2011 and peaked in June with a flow of approximately 150,000 cfs. The peak flow was sustained for two weeks. The dam releases have had a discernible impact on the Missouri River throughout this section. The 2011 flood has highlighted the critical need for quantifying the complex interaction between the regional geomorphology and human activities. It is necessary to first understand and quantify the historical impacts of the dams in order to determine the impact of the 2011 flood on channel planform, morphology, and sediment dynamics. We have created a spatial-temporal conceptual model of the governing fluvial and deltaic processes for the reach. Methods used for the development of the conceptual model include interpretation of repeat aerial photography, historical streamgage data, historical cross-sectional surveys, in addition to ground-truthing data with sediment cores, channel surveys, and dendrogeomorphic tools. Preliminary results indicate that prior to the 2011 flood the reach had achieved a dynamic equilibrium in response to dam closure and subsequent managed flows. The perturbation from the dam closure attenuated over approximately a 30-year period. Cross-sectional analysis indicates the reach just below the Garrison Dam increased in capacity over this period and the lower end of the reach (just upstream of the delta) either maintained capacity or experienced a reduction. Analysis of channel planform through repeat aerial photography suggests channel adjustment of varying types and degrees. Loss of islands and erosion has occurred in the 20 miles just below the dam; the next 30 miles have generally remained metastable and many islands in the remaining 20 miles of the river have become bank-attached. Loss of conveyance and increased frequency and growth of islands has occurred in the delta above the reservoir. However, the Upper Missouri River is still responding to the historic flood of 2011 and analysis is ongoing.
19. 'Transverse Bracing, 3 180'61/2' c. to c. End ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. 'Transverse Bracing, 3 - 180'-6-1/2' c. to c. End Pins Sing. Tr. Thro' Spans, C.O. 839 10th Crossing Sacramento River, C.O. 840 11th Crossing Sacramento River, C.O. 841 13th Crossing Sacramento River, Sacramento Division, So. Pac. Co., The Phoenix Bridge Co., C.O's. 839, 840 & 841, Drawing #4, Eng'r - C. Scheidl, Draftsman - B. Heald, Scale 1' = 1'-0', April 13th 1901.' - Southern Pacific Railroad Shasta Route, Bridge No. 310.58, Milepost 310.58, Sims, Shasta County, CA
Level II scour analysis for Bridge 63 (CHESTH00090063) on Town Highway 9, crossing the Williams River, Chester, Vermont

USGS Publications Warehouse

Flynn, Robert H.

1997-01-01

year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.
Level II scour analysis for Bridge 43 (SPRICYBRIG0043) on Bridge Street, crossing the Black River, Springfield, Vermont

USGS Publications Warehouse

Ivanoff, Michael A.; Medalie, Laura

1997-01-01

year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.
River sinuosity changes as indicators of the possible neotectonic activity - a case study on the Danube River between Paks (Hungary) and Beograd (Serbia)

NASA Astrophysics Data System (ADS)

Petrovszki, Judit

2010-05-01

The meandering, pre-regulation river planforms of the Danube River, between Paks (Hungary) and Beograd (Serbia) was digitized from the map sheets of the Second Military Survey of the Habsburg Empire (Timár et al., 2006). These maps were surveyed before or simultaneously with the river control works, so it is possible to follow the natural riverbeds, the natural changing of the meandering structure. The sinuosity values were calculated with different window sizes, and displayed in a spectrum-like diagram (sinuosity spectra; after van Balen et al., 2008). The channel sinuosity of this river is analyzed in order to draw conclusions on the neotectonic activity of the western part of the Great Hungarian Plain. Several points of sinuosity change were identified. To prove that these are of neotectonic origin, a neotectonic map and seismic sections crossing the study area, were also analyzed. Significant sinuosity changes (low to high or high to low), spatially correlated to linear features identified in seismic survey sections or in tectonic maps (Horváth et al., 2006), indicate their neotectonic activity (Ouchi, 1985; Timár, 2003; Zámolyi et al., 2010). Upstream of the Hungarian-Serbian border, the Duna (Danube) has anabranching planform, the Baracskai-Duna is the main anabranch. There is a fault on the neotectonic map, crossing both rivers, and cause the decreasing of the sinuosity. The vertical activity of the structural line, which is more or less parallel to the international border, is verified by the sinuosity change. The direction of the change (from high to low sinuosity values) correlates with the normal fault character, shown on the map. Another significant sinuosity change occurs downstream of the Drava River confluence. The explanation of this change can be of two kinds. First, there is a known tectonic feature along the Drava River, with dextral faulting. The sinuosity increase could indicate a small active vertical component of this structural line. However, another possible explanation is based on the significant sediment load of the tributary, that is naturally decreases the river sinuosity. Horváth, F., Bada, G., Windhoffer, G., Csontos, L., Dombrádi, E., Dövényi, P., Fodor, L., Grenerczy, Gy., Síkhegyi, F., Szafián, P., Székely, B., Timár, G., Tóth, L., Tóth, T. (2006): A Pannon-medence jelenkori geodinamikájának atlasza: Euro-konform térképsorozat és magyarázó. Magyar Geofizika 47(4), 133-137. Ouchi, S. (1985): Response of alluvial rivers to slow active tectonic movement. Geol. Soc. Am. Bull. 96, 504-515. Timár, G. (2003): Controls on channel sinuosity changes: a case study of the Tisza River, the Great Hungarian Plain. Quaternary Sci. Rev. 22, 2199-2207. Timár, G., Molnár, G., Székely, B., Biszak, S., Varga, J., Jankó, A. (2006): Digitized maps of the Habsburg Empire - The map sheets of the second military survey and their georeferenced version. Arcanum, Budapest, 59 p. van Balen, R. T., Kasse, C., Moor, J. (2008): Impact of groundwater flow on meandering; example from the Geul river, the Netherlands. Earth Surf. Process. and Landf. 33(13), 2010-2028. Zámolyi, A., Székely, B., Draganits, E., Timár, G. (2010): Neotectonic control on river sinuosity at the western margin of the Little Hungarian Plain. Geomorph., in press, DOI: 10.1016/j.geomorph.2009.06.028
Synthesis of natural flows at selected sites in and near the Milk River basin, Montana, 1928-89

USGS Publications Warehouse

Cary, L.E.; Parrett, Charles

1995-01-01

Natural monthly streamflows were synthesized for the years 1928-89 at 2 sites in the St. Mary River Basin and 11 sites in the Milk River Basin in north- central Montana. The sites are represented as nodes in a streamflow accounting model being developed by the Bureau of Reclamation for the Milk River Basin. Recorded flows at most sites have been affected by human activities, including reservoir storage and irrigation diversions. The flows at the model nodes were corrected for the effects of these activities to obtain synthesized flows. The synthesized flows at nodes with seasonal and short-term records were extended using a statistical technique. The methods of synthesis varied, depending on upstream activities and information available. Flows at sites in the St. Mary River Basin and at the Milk River at Eastern Crossing of International Boundary pre- viously had been synthesized. The flows at mainstem sites downstream from the Milk River at Eastern Crossing were synthesized by adding synthesized natural runoff from intervening drainage areas to natural flows for Milk River at Eastern Crossing. Natural runoff from intervening drainage areas was estimated by multiplying recorded flows at selected index gaging stations on tributary streams by the ratio of the intervening drainage area to the combined drainage area of the index stations. The recorded flows for Milk River at Western Crossing of International Boundary and for Peoples Creek near Dodson, Montana, were assumed to be natural flows. The synthesized annual flows at the mouth of the Milk River compared favorably with the recorded flows near the mouth when the effects of upstream irrigation were considered.
CTUIR Grande Ronde River Basin Watershed Restoration Program McCoy Creek/McIntyre Creek Road Crossing, 1996-1998 Progress Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Childs, Allen B.

1999-07-01

This Annual Report provides a detailed overview of watershed restoration accomplishments achieved by the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and project partners in the Upper Grande Ronde River Basin under contract with the Bonneville Power Administration (BPA) during the period July 1, 1997 through June 30, 1998. The Contract Agreement entitled McCoy Meadows Watershed Restoration Project (Project No.96-83-01) includes habitat restoration planning, design, and implementation in two project areas--the McCoy Meadows Ranch located in the Meadow, McCoy, and McIntyre Creek subbasins on private land and the Mainstem Grande Ronde River Habitat Enhancement Project located on private andmore » National Forest System lands near Bird Tract Springs along the Grande Ronde River. During the contract period, the CTUIR and partners (Mark and Lorna Tipperman, landowners), Oregon Department of Environmental Quality (ODEQ), U.S. Environmental Protection Agency (EPA), Oregon Department of Fish and Wildlife (ODFW), and Natural Resource Conservation Service (NRCS) initiated phase 1 construction of the McCoy Meadows Restoration Project. Phase 1 involved reintroduction of a segment of McCoy Creek from its existing channelized configuration into a historic meander channel. Project efforts included bioengineering and tree/shrub planting and protection, transporting salvaged cottonwood tree boles and limbs from offsite source to the project area for utilization by resident beaver populations for forage and dam construction materials, relocation of existing BPA/ODFW riparian corridor fencing to outer edges of meadow floodplain, establishment of pre-project photo points, and coordination of other monitoring and evaluation efforts being led by other project partners including groundwater monitoring wells, channel cross sections, water quality monitoring stations, juvenile population sampling index sites, redd surveys, and habitat surveys. Project activities also included coordination with the U.S. Forest Service, Wallowa-Whitman National Forest, LaGrande Ranger District (USFS) on the Forest Road 2137 (McIntyre Road) Relocation and Obliteration Project and the McCoy Creek crossing. The USFS completed engineering designs under the cooperative effort for the McCoy Creek crossing. Project activities accomplished on the Upper Mainstem Large Wood Addition Project included placement of approximately 120 whole trees to enhance instream structural diversity, pool habitat quality, streambank stability, and improved floodplain morphology. Project activities accomplished on the Mainstem Grande Ronde Habitat Enhancement Project included coordination with landowners (Shauna Musgrove of Cuhna Ranches, Dean Stone, and the Wallowa-Whitman National Forest, LaGrande Ranger District) to develop a habitat enhancement/restoration project opportunity along a 3 mile section of the mainstem Grande Ronde River and major tributaries including the lower reaches of Bear Creek and Jordan Creek. Upon securing an agreement with the landowners, project partners including the CTUIR, ODFW, NRCS, and USFS initiated development of project objectives and site-specific designs. By June 1998, project designs were completed and preparations nearly complete to initiate onsite project construction.« less
Hydrogeomorphological variability and ecological impacts in straight and restored river reach sections

NASA Astrophysics Data System (ADS)

Schäppi, B.; Molnar, P.; Perona, P.; Tockner, K.; Burlando, P.

2009-04-01

Healthy floodplain ecosystems are characterized by high habitat diversity which tends to be lost in straightened channelized rivers. River restoration projects aim to increase habitat heterogeneity by re-establishing natural flow conditions and/or re-activating geomorphic processes in straightened reaches. The success of such projects is usually measured by means of structural and functional hydrogeomorphic and ecological indicators. Important indicators include flow variables and morphological features such as flow depth, velocity, shore line length, exposed gravel area and wetted river width. Also important are the rates at which these variables and features change under varying streamflow. A high spatial variability in the indicators is generally connected with high habitat diversity. The temporal availability and spatial distribution of both aquatic and riparian habitats control the composition and diversity of benthic organisms, fish, and riparian communities. Spatial heterogeneity provides refugia, i.e. areas from which recolonization after a disturbance event may occur. In addition, it facilitates the transfer of organisms and matter across the aquatic and terrestrial interface, thereby increasing the overall functional performance of coupled river-riparian ecosystems. However the habitat diversity can be maintained over time only if there are frequent disturbances such as periodic floods that reset the system and create new germination sites for pioneer vegetation and rework the channel bed to form new aquatic habitat. Therefore the flow and morphology indicators need to be investigated on spatial as well as on temporal scales. Traditionally, these indicators are measured in the field albeit most measurements can be carried out only at low flow conditions. We propose that flow simulations with a 2d hydrodynamic model may be used for a fast and convenient assessment of indicators of flow variables and morphological features with relatively little calibration required and we illustrate an example thereof. The advantage of using computer simulations as compared to field observations is that a range of discharges can be investigated. Using a flood frequency analysis the return period of simulated flows can be estimated and translated into frequency-dependent habitat types. In order to investigate how flow variables change, we conducted a series of 2d flow simulations at different flow rates along the prealpine Thur River (Switzerland) consisting of both restored and straight reaches. Restoration basically consisted of widening the river cross-section and allowing a natural morphology to form. The simulated flow variables (flow depth and velocity) were then analyzed separately for the two reaches. The distributions of the both variables for the restored reach were significantly different from the straight reach, most notably an increase in the variance was observed. In order to analyze the temporal variability we investigated the development of the riverbed morphology over time using different digital elevation models combined with cross section data measured at annual intervals. Spatially explicit erosion and deposition patterns were derived from this analysis. The riverbed topography at different dates was then used to analyze the temporal evolution of the flow indicators for the different flow conditions. Comparisons between the restored and straight reaches allow us to assess the success of river restoration in terms of flow variability and morphological complexity.
25. VIEW OF McGREGOR BRIDGE (18811936), CROSSING THE MERRIMACK RIVER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. VIEW OF McGREGOR BRIDGE (1881-1936), CROSSING THE MERRIMACK RIVER AT BRIDGE STREET, LOOKING SOUTHEAST. NORTH ELEVATION OF DOUBLE-DECKED, THREE-SPAN DOUGLAS PATENT PARABOLIC IRON TRUSS ERECTED BY CORRUGATED METAL COMPANY (BERLIN IRON BRIDGE COMPANY, BERLIN, CT) From 'Bridge Street Bridge', photographer and date unknown. - Notre Dame Bridge, Spanning Merrimack River on Bridge Street, Manchester, Hillsborough County, NH
Statistical and Conceptual Model Testing Geomorphic Principles through Quantification in the Middle Rio Grande River, NM.

NASA Astrophysics Data System (ADS)

Posner, A. J.

2017-12-01

The Middle Rio Grande River (MRG) traverses New Mexico from Cochiti to Elephant Butte reservoirs. Since the 1100s, cultivating and inhabiting the valley of this alluvial river has required various river training works. The mid-20th century saw a concerted effort to tame the river through channelization, Jetty Jacks, and dam construction. A challenge for river managers is to better understand the interactions between a river training works, dam construction, and the geomorphic adjustments of a desert river driven by spring snowmelt and summer thunderstorms carrying water and large sediment inputs from upstream and ephemeral tributaries. Due to its importance to the region, a vast wealth of data exists for conditions along the MRG. The investigation presented herein builds upon previous efforts by combining hydraulic model results, digitized planforms, and stream gage records in various statistical and conceptual models in order to test our understanding of this complex system. Spatially continuous variables were clipped by a set of river cross section data that is collected at decadal intervals since the early 1960s, creating a spatially homogenous database upon which various statistical testing was implemented. Conceptual models relate forcing variables and response variables to estimate river planform changes. The developed database, represents a unique opportunity to quantify and test geomorphic conceptual models in the unique characteristics of the MRG. The results of this investigation provides a spatially distributed characterization of planform variable changes, permitting managers to predict planform at a much higher resolution than previously available, and a better understanding of the relationship between flow regime and planform changes such as changes to longitudinal slope, sinuosity, and width. Lastly, data analysis and model interpretation led to the development of a new conceptual model for the impact of ephemeral tributaries in alluvial rivers.
The Hidden Tragedy of Rivers: A Decade of Unintentional Fatal Drowning in Australia.

PubMed

Peden, Amy E; Franklin, Richard C; Leggat, Peter A

2016-01-01

Describe unintentional drowning deaths in rivers, creeks and streams (rivers) in Australia and identify risk factors to inform prevention. This study is a cross-sectional, total population audit of all unintentional fatal drownings in Australian rivers between 1-July-2002 and 30-June-2012 using Australian coronial data. A modified Bonferroni test has been applied, deeming statistical significance p<0.03 and p<0.04 respectively. Rivers (n = 770; 26.6%) were the leading location among the 2,892 people who died from unintentional fatal drowning. This is a rate of 0.37/100,000 people / annum. Within river drowning deaths common groups include; males (80.4%), adults (85.3%), adults who have consumed alcohol (25.5%), people who fell in (21.3%), people involved in non-aquatic transport incidents (18.2%) and locals (74.0%). Children were 1.75 times more likely than adults (p<0.04) to drown in rivers as a result of a fall and adults 1.50 times more likely to drown in rivers as a result of watercraft incidents when compared to children. When compared to males, females were 2.27 and 4.45 times respectively more likely to drown in rivers as a result of incidents involving non-aquatic transport (p<0.04) and being swept away by floodwaters (p<0.04). Males were 2.66 and 4.27 times respectively more likely to drown in rivers as a result of watercraft incidents (p<0.04) and as a result of jumping in (p<0.04) when compared to females. While rivers are the leading location for drowning in Australia, little is understood about the risks. This study has identified key groups (males, adults, locals) and activities. While males were more likely to drown, the risk profile for females differed.
27. Photographic copy of ink on linen drawing (at the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. Photographic copy of ink on linen drawing (at the archives of Niagara Mohawk Power Corporation, 300 Eric Boulevard West, Syracuse, New York 13202), Strand, Draftsman, July 3, 1913. Sheet 1-260, Finch, Pruyn & Company and International Paper Company. Detail of concrete dam and headgate wall. Detail showing typical cross section through the dam. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY
35. Photocopy of original plan (on file at City of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

35. Photocopy of original plan (on file at City of New York Department of Ports, International Trade, and Commerce) no date CONTRACT 1519/CITY OF NEW YORK/DEPARTMENT OF DOCKS AND FERRIES/ FREIGHT SHED/ W. 55TH ST. IMPROVEMENT/BOROUGH OF MANHATTAN/ CROSS SECTION AND DETAILS - PIER SHED (Drawing 8 of 16) - West 55th Street & West 56th Street Piers, Hudson River at West Fifty-fifth & West Fifty-sixth Streets, Manhattan, New York County, NY

Use of the routing procedure to study dye and gas transport in the West Fork Trinity River, Texas

USGS Publications Warehouse

Jobson, Harvey E.; Rathbun, R.E.

1984-01-01

Rhodamine-WT dye, ethylene, and propane were injected at three sites along a 21.6-kilometer reach of the West Fork Trinity River below Fort Worth, Texas. Complete dye concentration versus time curves and peak gas concentrations were measured at three cross sections below each injection. The peak dye concentrations were located and samples were collected at about three-hour intervals for as many as six additional cross sections. These data were analyzed to determine the longitudinal dispersion coefficients as well as the gas desorption coefficients using both standard techniques and a numerical routing procedure. The routing procedure, using a Lagrangian transport model to minimize numerical dispersion, provided better estimates of the dispersion coefficient than did the method of moments. At a steady flow of about 0.76 m2/s, the dispersion coefficient varied from about 0.7 m2/s in a reach contained within a single deep pool to about 2.0 m2/s in a reach containing riffles and small pools. The bulk desorption coefficients computed using the routing procedure and the standard peak method were essentially the same. The liquid film coefficient could also be obtained using the routing procedure. Both the bulk desorption coefficient and the liquid film coefficient were much smaller in the pooled reach than in the reaches containing riffles.
Salmonids, stream temperatures, and solar loading--modeling the shade provided to the Klamath River by vegetation and geomorphology

USGS Publications Warehouse

Forney, William M.; Soulard, Christopher E.; Chickadel, C. Christopher

2013-01-01

The U.S. Geological Survey is studying approaches to characterize the thermal regulation of water and the dynamics of cold water refugia. High temperatures have physiological impacts on anadromous fish species. Factors affecting the presence, variability, and quality of thermal refugia are known, such as riverine and watershed processes, hyporheic flows, deep pools and bathymetric factors, thermal stratification of reservoirs, and other broader climatic considerations. This research develops a conceptual model and methodological techniques to quantify the change in solar insolation load to the Klamath River caused by riparian and floodplain vegetation, the morphology of the river, and the orientation and topographic characteristics of its watersheds. Using multiple scales of input data from digital elevation models and airborne light detection and ranging (LiDAR) derivatives, different analysis methods yielded three different model results. These models are correlated with thermal infrared imagery for ground-truth information at the focal confluence with the Scott River. Results from nonparametric correlation tests, geostatistical cross-covariograms, and cross-correlograms indicate that statistical relationships between the insolation models and the thermal infrared imagery exist and are significant. Furthermore, the use of geostatistics provides insights to the spatial structure of the relationships that would not be apparent otherwise. To incorporate a more complete representation of the temperature dynamics in the river system, other variables including the factors mentioned above, and their influence on solar loading, are discussed. With similar datasets, these methods could be applied to any river in the United States—especially those listed as temperature impaired under Section 303(d) of the Clean Water Act—or international riverine systems. Considering the importance of thermal refugia for aquatic species, these methods can help investigate opportunities for riparian restoration, identify problematic reaches unlikely to provide good habitat, and simulate changes to solar loading estimates from alternative landscape configurations.
Comparison of methods for determining streamflow requirements for aquatic habitat protection at selected sites on the Assabet and Charles Rivers, Eastern Massachusetts, 2000-02

USGS Publications Warehouse

Parker, Gene W.; Armstrong, David S.; Richards, Todd A.

2004-01-01

Four methods used to determine streamflow requirements for habitat protection at nine critical riffle reaches in the Assabet River and Charles River Basins were compared. The methods include three standard setting techniques?R2Cross, Wetted Perimeter, and Tennant?and a diagnostic method, the Range of Variability Approach. One study reach is on the main stem of the Assabet River, four reaches are on tributaries to the Assabet River (Cold Harbor Brook, Danforth Brook, Fort Meadow Brook, and Elizabeth Brook), three are on the main stem of the Charles River, and one is on a tributary to the Charles River (Mine Brook). The strength of the R2Cross and Wetted-Perimeter methods is that they may be applied at ungaged locations whereas the Tennant method and the Range of Variability Approach require a period of streamflow record for analysis. Fish community assessments conducted at or near riffle sites in flowing reaches of the Assabet River and Charles River Basins were used to indicate ecological conditions. The fish communities in the main stem and tributary reaches of both the Assabet and Charles River Basins indicated degraded aquatic ecosystems. However, the degree of degradation differs between the two basins. The extreme predominance of tolerant, generalist species in the Charles River fish community demon-strates the cumulative impacts of flow, habitat, and water-chemistry degradation, combined with the effects of nearby impoundments and changing land use. The range of discharges for nine ungaged riffle reaches defined by the median R2Cross 3-of-3 criteria, R2Cross 2-of-3 criteria, and Wetted-Perimeter streamflow requirements, was 0.86 cubic foot per second per square mile, 0.18 cubic foot per second per square mile, and 0.23 cubic foot per second per square mile, respectively. Application of R2Cross and Wetted-Perimeter methods to sites with altered streamflows or at sites that are riffles only at low to moderate flows can result in a greater variability of streamflow requirements than would result if the methods were applied to riffles on natural channels with unaltered streamflows. The R2Cross 2-of-3 criteria and the Wetted-Perimeter streamflow requirements for the Assabet and Charles River sites show narrower interquartile ranges and lower median streamflow requirements than for 10 index streamflow-gaging stations in southern New England. This is especially evident for the R2Cross 2-of-3 criteria and Wetted-Perimeter results that were close to half of the flow requirements determined at the 10 southern New England stations. The R2Cross and Wetted-Perimeter methods were also compared to the Range of Variability Approach analysis and the Tennant Method. The median R2Cross 3-of-3 criteria streamflow requirement for the nine riffles is close to the 75th percentile of the monthly mean flows during the summer low-flow period from six streamflow-gaging stations near the Assabet and Charles River Basins having mostly unaltered flow. This streamflow requirement is close to the median Tennant 40-percent-flow requirement for good habitat condi-tion for the same six nearby stations. The R2Cross 2-of-3 criteria and Wetted-Perimeter results were less than the 25th-percentile of monthly mean flows during the summer months for the six stations. These streamflow requirements are in the poor habitat range as indicated by a Tennant analysis of the same six stations. These comparisons indicate that the R2Cross and Wetted-Perimeter methods underestimate streamflow requirements when applied to sites in smaller drainage areas and channels that are runs at higher flows.
Formation and maintenance of single-thread tie channels entering floodplain lakes: Observations from three diverse river systems

NASA Astrophysics Data System (ADS)

Rowland, J. C.; Dietrich, W. E.; Day, G.; Parker, G.

2009-06-01

Tie channels connect rivers to floodplain lakes on many lowland rivers and thereby play a central role in floodplain sedimentology and ecology; yet they are generally unrecognized and little studied. Here we report the results of field studies focused on tie channel origin and morphodynamics in the following three contrasting systems: the Middle Fly River (Papua New Guinea), the Lower Mississippi River, and Birch Creek in Alaska. Across these river systems, tie channels vary by an order of magnitude in size but exhibit the same characteristic morphology and appear to develop and evolve by a similar set of processes. In all three systems, the channels are characterized by a narrow, leveed, single-thread morphology with maximum width approximately one tenth the width of the mainstem river. The channels typically have a V-shaped cross section, unlike most fluvial channels. These channels develop as lakes become isolated from the river by sedimentation. Narrowing of the connection between river and lake causes a sediment-laden jet to develop. Levees develop along the margins of the jet leading to channel emergence and eventual levee aggradation to the height of the mainstem levees. Bidirectional flow in these channels is common. Outflows from the lake scour sediment and prevent channel blockage. We propose that channel geometry and size are then controlled by a dynamic balance between channel narrowing by suspended sediment deposition and incision and widening by mass failure of banks during outflows. Tie channels are laterally stable and may convey flow for hundreds to a few thousand of years.
Use of induced polarization to characterize the hydrogeologic framework of the zone of surface‐water/groundwater exchange at the Hanford 300 Area, WA

USGS Publications Warehouse

Slater, Lee; Ntarlagiannis, Dimitrios; Day-Lewis, Frederick D.; Mwakanyamale, Kisa; Lane, John W.; Ward, Andy; Versteeg, Roelof J.

2010-01-01

An extensive continuous waterborne electrical imaging (CWEI) survey was conducted along the Columbia River corridor adjacent to the U.S. Department of Energy (DOE) Hanford 300 Area, WA, in order to improve the conceptual model for exchange between surface water and U‐contaminated groundwater. The primary objective was to determine spatial variability in the depth to the Hanford‐Ringold (H‐R) contact, an important lithologic boundary that limits vertical transport of groundwater along the river corridor. Resistivity and induced polarization (IP) measurements were performed along six survey lines parallel to the shore (each greater than 2.5 km in length), with a measurement recorded every 0.5–3.0 m depending on survey speed, resulting in approximately 65,000 measurements. The H‐R contact was clearly resolved in images of the normalized chargeability along the river corridor due to the large contrast in surface area (hence polarizability) of the granular material between the two lithologic units. Cross sections of the lithologic structure along the river corridor reveal a large variation in the thickness of the overlying Hanford unit (the aquifer through which contaminated groundwater discharges to the river) and clearly identify locations along the river corridor where the underlying Ringold unit is exposed to the riverbed. Knowing the distribution of the Hanford and Ringold units along the river corridor substantially improves the conceptual model for the hydrogeologic framework regulating U exchange between groundwater and Columbia River water relative to current models based on projections of data from boreholes on land into the river.
Heat tracing to determine spatial patterns of hyporheic exchange across a river transect

NASA Astrophysics Data System (ADS)

Lu, Chengpeng; Chen, Shuai; Zhang, Ying; Su, Xiaoru; Chen, Guohao

2017-09-01

Significant spatial variability of water fluxes may exist at the water-sediment interface in river channels and has great influence on a variety of water issues. Understanding the complicated flow systems controlling the flux exchanges along an entire river is often limited due to averaging of parameters or the small number of discrete point measurements usually used. This study investigated the spatial pattern of the hyporheic flux exchange across a river transect in China, using the heat tracing approach. This was done with measurements of temperature at high spatial resolution during a 64-h monitoring period and using the data to identify the spatial pattern of the hyporheic exchange flux with the aid of a one-dimensional conduction-advection-dispersion model (VFLUX). The threshold of neutral exchange was considered as 126 L m-2 d-1 in this study and the heat tracing results showed that the change patterns of vertical hyporheic flux varied with buried depth along the river transect; however, the hyporheic flux was not simply controlled by the streambed hydraulic conductivity and water depth in the river transect. Also, lateral flow dominated the hyporheic process within the shallow high-permeability streambed, while the vertical flow was dominant in the deep low-permeability streambed. The spatial pattern of hyporheic exchange across the river transect was naturally controlled by the heterogeneity of the streambed and the bedform of the stream cross-section. Consequently, a two-dimensional conceptual illustration of the hyporheic process across the river transect is proposed, which could be applicable to river transects of similar conditions.
High Resolution Airborne Shallow Water Mapping

NASA Astrophysics Data System (ADS)

Steinbacher, F.; Pfennigbauer, M.; Aufleger, M.; Ullrich, A.

2012-07-01

In order to meet the requirements of the European Water Framework Directive (EU-WFD), authorities face the problem of repeatedly performing area-wide surveying of all kinds of inland waters. Especially for mid-sized or small rivers this is a considerable challenge imposing insurmountable logistical efforts and costs. It is therefore investigated if large-scale surveying of a river system on an operational basis is feasible by employing airborne hydrographic laser scanning. In cooperation with the Bavarian Water Authority (WWA Weilheim) a pilot project was initiated by the Unit of Hydraulic Engineering at the University of Innsbruck and RIEGL Laser Measurement Systems exploiting the possibilities of a new LIDAR measurement system with high spatial resolution and high measurement rate to capture about 70 km of riverbed and foreland for the river Loisach in Bavaria/Germany and the estuary and parts of the shoreline (about 40km in length) of lake Ammersee. The entire area surveyed was referenced to classic terrestrial cross-section surveys with the aim to derive products for the monitoring and managing needs of the inland water bodies forced by the EU-WFD. The survey was performed in July 2011 by helicopter and airplane and took 3 days in total. In addition, high resolution areal images were taken to provide an optical reference, offering a wide range of possibilities on further research, monitoring, and managing responsibilities. The operating altitude was about 500 m to maintain eye-safety, even for the aided eye, the airspeed was about 55 kts for the helicopter and 75 kts for the aircraft. The helicopter was used in the alpine regions while the fixed wing aircraft was used in the plains and the urban area, using appropriate scan rates to receive evenly distributed point clouds. The resulting point density ranged from 10 to 25 points per square meter. By carefully selecting days with optimum water quality, satisfactory penetration down to the river bed was achieved throughout the project. During the data processing meshes for multiple purposes like monitoring sediment transport or accumulation and hydro-dynamic numeric modeling were generated. The meshes were professionally conditioned considering the adherence of, both, geometric and physical mesh quality criterions. Whereas the research is focused on the design and implementation of monitoring database structures, the airborne hydrographic data are also made available for classical processing means (cross sections, longitudinal section).
Child Survival Strategies: Assessment of Knowledge and Practice of Rural Women of Reproductive Age in Cross River State, Nigeria.

PubMed

Etokidem, Aniekan Jumbo; Johnson, Ofonime

2016-01-01

Introduction . Nigeria is one of the five countries that account for about 50% of under-five mortality in the world. The objective of this study was to assess the knowledge and practice of child survival strategies among rural community caregivers in Cross River State of Nigeria. Materials and Methods . This descriptive cross-sectional survey used a pretested questionnaire to obtain information from 150 women of reproductive age. Data analysis was done using SPSS version 20. Results . The child survival strategy known to most of the respondents was oral rehydration therapy as indicated by 98% followed by female education by 73.3% and immunization by 67.3%. Only 20% of the respondents had adequate knowledge of frequency of weighing a child while only 32.7% knew that breastfeeding should be continued even if the child had diarrhea. More respondents with nonformal education (83.3%) practiced exclusive breastfeeding of their last children compared to respondents with primary education (77.3%), secondary education (74.2%), and tertiary education (72.2%). Conclusion . Although respondents demonstrated adequate knowledge and practice of most of the strategies, there was evidence of gaps, including myths and misconceptions that could mar efforts towards reducing child morbidity and mortality in the state.
River network bedload model: a tool to investigate the impact of flow regulation on grain size distribution in a large Alpine catchment

NASA Astrophysics Data System (ADS)

Costa, Anna; Molnar, Peter

2017-04-01

Sediment transport rates along rivers and the grain size distribution (GSD) of coarse channel bed sediment are the result of the long term balance between transport capacity and sediment supply. Transport capacity, mainly a function of channel geometry and flow competence, can be altered by changes in climatic forcing as well as by human activities. In Alpine rivers it is hydropower production systems that are the main causes of modification to the transport capacity of water courses through flow regulation, leading over longer time scales to the adjustment of river bed GSDs. We developed a river network bedload transport model to evaluate the impacts of hydropower on the transfer of sediments and the GSDs of the Upper Rhône basin, a 5,200 km2 catchment located in the Swiss Alps. Many large reservoirs for hydropower production have been built along the main tributaries of the Rhône River since the 1960s, resulting in a complex system of intakes, tunnels, and pumping stations. Sediment storage behind dams and intakes, is accompanied by altered discharge due to hydropower operations, mainly higher flow in winter and lower in summer. It is expected that this change in flow regime may have resulted in different bedload transport. However, due the non-linear, threshold-based nature of the relation between discharge and sediment mobilization, the effects of changed hydraulic conditions are not easily deducible, and because observations of bedload in pre- and post-dam conditions are usually not available, a modelling approach is often necessary. In our modelling approach, the river network is conceptualized as a series of connected links (river reaches). Average geometric characteristics of each link (width, length, and slope of cross section) are extracted from digital elevation data, while surface roughness coefficients are assigned based on the GSD. Under the assumptions of rectangular prismatic cross sections and normal flow conditions, bed shear stress is estimated from available time series of daily discharge distributed along the river network. Potential bedload transport is estimated by the Wilcock and Crowe surface-based model for the entire GSD. Mass balance between transport capacity and sediment supply, applied to each individual grain size, determines the actual transport and the resulting GSD of the channel bed. Channel bed erosion is allowed through a long-term erosion rate. Sediment input from hillslopes is included as lateral sediment flux. Initial and boundary conditions are set based on available data of GSDs, while an approximation of the depth of the mobile bed is selected through sensitivity analysis. With the river network bedload model we aim to estimate the effect of flow regulation, i.e. altered transport capacity, on sediment transport and GSD of the entire Rhône river system. The model can also be applied as a tool to explore possible changes in bedload transport and channel GSDs under different discharge scenarios based, for example, on climate change projections or modified hydropower operation policies.
Geologic map of the Topock 7.5’ quadrangle, Arizona and California

USGS Publications Warehouse

Howard, Keith A.; John, Barbara E.; Nielson, Jane E.; Miller, Julia M.G.; Wooden, Joseph L.

2013-01-01

The Topock quadrangle exposes a structurally complex part of the Colorado River extensional corridor and also exposes deposits that record landscape evolution during the history of the Colorado River. Paleoproterozoic gneisses and Mesoproterozoic granitoids and intrusive sheets are exposed through tilted cross-sectional thicknesses of many kilometers. Intruding them are a series of Mesozoic to Tertiary igneous rocks including dismembered parts of the Late Cretaceous Chemehuevi Mountains Plutonic Suite. Plutons of this suite in Arizona, if structurally restored for Miocene extension, formed cupolas capping the Chemehuevi Mountains batholith in California. Thick (1–3 km) Miocene sections of volcanic rocks, sedimentary breccias, conglomerate, and sandstone rest nonconformably on the Proterozoic rocks and record the structural and depositional evolution of the Colorado River extensional corridor. Four major Miocene low-angle normal faults and a steep block-bounding fault that developed during this episode divide the deformed rocks of the quadrangle into major structural plates and tilted blocks in and east of the Chemehuevi Mountains core complex. The low-angle faults attenuate crustal section, superposing supracrustal and upper crustal rocks against gneisses and granitoids originally from deeper crustal levels. The transverse block-bounding Gold Dome Fault Zone juxtaposes two large hanging-wall blocks, each tilted 90°, and the fault zone splays at its tip into folds in layered Miocene rocks. A synfaulting intrusion occupies the triangular zone where the folded strata detached from an inside corner along this fault between the tilt blocks. Post-extensional upper Miocene to Quaternary strata, locally deformed, record post-extensional landscape evolution, including several Pliocene and younger aggradational episodes in the Colorado River valley and intervening degradation episodes. The aggradational sequences include (1) the Bouse Formation, (2) fluvial deposits correlated with the alluvium of Bullhead City, (3) the younger fluvial boulder conglomerate of Bat Cave Wash, (4) the fluvial Chemehuevi Formation and related valley-margin deposits, and (5) fluvial Holocene deposits under the river and the valley floor. These fluvial records of Colorado River deposition are interspersed with piedmont alluvial fan deposits of several ages.
13. A streetcar crosses the Cuyahoga River in the waning ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. A streetcar crosses the Cuyahoga River in the waning days of Cleveland's trolley age. Copy of photograph taken by Herbert H. Harwood, Jr., Baltimore, Maryland, photo courtesy Mr. Harwood - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH
[Effect of Seasonal Temperature Increasing on Nitrogen Mineralization in Soil of the Water Level Fluctuating Zone of Three Gorge Tributary During the Dry Period].

PubMed

Lin, Jun-jie; Zhang, Shuai; Liu, Dan; Zhou, Bin; Xiao, Xiao-jun; Ma, Hui-yan; Yu, Zhi-guo

2016-02-15

To reveal the effect of seasonal temperature increasing on nitrogen mineralization in soil of the water level fluctuating soil zone of three gorge reservoir areas in the Yangtze river tributary during the dry period, surface soils were collected from the water level fluctuating zone of Pengxi river crossing two hydrological sections, i.e., upstream and downstream and three water level altitudes, 155 m (low), 165 m (middle) and 175 m (high). We incubated the soil at 25 degrees C and 35 degrees C to determine the transformation rates of nitrogen in soil of Pengxi river basin during the dry period. The result showed that TN and NO3- -N contents in the soil of upstream section and higher (175 m) altitude of water level were higher than those in downstream and low (165 m) altitude of water level, whereas the pattern for NH4+ -N was different, with higher NH4+ -N contents in downstream and low water level. The inorganic nitrogen was dominated by NO3- -N, which accounted for up to 57.4%-84.7% of inorganic nitrogen. Generally, soil ammoniation, nitration and net N mineralization increased with the rising water level altitude and stream sections (P < 0.05). In summary, nitration and net N mineralization significantly increased with increasing temperature, (P < 0.05), while ammoniation showed no difference (P > 0.05).
33 CFR 117.911 - Atlantic Intracoastal Waterway, Little River to Savannah River.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., Little River to Savannah River. 117.911 Section 117.911 Navigation and Navigable Waters COAST GUARD... § 117.911 Atlantic Intracoastal Waterway, Little River to Savannah River. (a) General. Public vessels of... Register citations affecting § 117.911, see the List of CFR Sections Affected, which appears in the Finding...
Local and non-local effects of spanwise finite perturbations in erodible river bathymetries

NASA Astrophysics Data System (ADS)

Musa, Mirko; Hill, Craig; Guala, Michele

2015-11-01

Laboratory experiments were performed to study the effect of axial-flow hydrokinetic turbine models on an erodible river bed under live-bed conditions. Results indicate that the presence of an operating turbine rotor creates a blockage in the mean flow which produces a remarkable geomorphic signature in the migrating bedforms. These impacts affect a local area downstream of the turbines when placed symmetrically with respect to the cross section of the channel. On the other hand, more interesting results are observed with an asymmetric installation of the turbines. This configuration demonstrates a stronger effect on the mean flow, resulting in a larger plan-wise distortion of the mean topography and differential migration patterns of bedforms. Different turbine installation arrangements and hub heights above the mean bed were investigated, focusing mainly on the perturbation of sediment transport characteristics influenced by the turbine wake. Additional results with spanwise modulated submerged walls explore the possibility to control river topography harvesting this type of geomorphic destabilization.
Water quality of the tidal Potomac River and estuary hydrologic data report, 1980 water year

USGS Publications Warehouse

Blanchard, Stephen; Coupe, R.H.; Woodward, J.C.

1982-01-01

This report contains data on the physical and chemical properties measured in the Tidal Potomac River and Estuary during the 1980 Water Year. Data were collected routinely at five stations, and periodically at 17 stations including three stations near the mouth of the Potomac River in Chesapeake Bay. Each of the five stations represent a cross section through which the transport of selected dissolved and suspended materials can be computed. The remaining stations represent locations at which data were collected for special synoptic studies such as salt water migration, and dissolved oxygen dynamics. Routinely, samples were analyzed for silica, nitrogen, phosphorus, chlorophyll-a, pheophytin, and suspended sediment. Additional samples were analyzed for organic carbon, calcium, manganese, magnesium, sodium, alkalinity, sulfate, iron, potassium, chloride, fluoride, seston, algal growth potential, adenosine triphosphate, nitrifying bacteria and dissolved-solids residue. In addition, solar radiation measurements and in-situ measurements of dissolved oxygen, specific conductance, pH, temperature, and Secchi disk transparency are reported. (USGS)
Changing Regulations of COD Pollution Load of Weihe River Watershed above TongGuan Section, China

NASA Astrophysics Data System (ADS)

Zhu, Lei; Liu, WanQing

2018-02-01

TongGuan Section of Weihe River Watershed is a provincial section between Shaanxi Province and Henan Province, China. Weihe River Watershed above TongGuan Section is taken as the research objective in this paper and COD is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a method—characteristic section load (CSLD) method is suggested and point and non-point source pollution loads of Weihe River Watershed above TongGuan Section are calculated in the rainy, normal and dry season in 2013. The results show that the monthly point source pollution loads of Weihe River Watershed above TongGuan Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above TongGuan Section change greatly and the non-point source pollution load proportions of total pollution load of COD decrease in the rainy, wet and normal period in turn.
Using CSLD Method to Calculate COD Pollution Load of Wei River Watershed above Huaxian Section, China

NASA Astrophysics Data System (ADS)

Zhu, Lei; Song, JinXi; Liu, WanQing

2017-12-01

Huaxian Section is the last hydrological and water quality monitoring section of Weihe River Watershed. Weihe River Watershed above Huaxian Section is taken as the research objective in this paper and COD is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads—characteristic section load(CSLD) method is suggested and point source pollution and non-point source pollution loads of Weihe River Watershed above Huaxian Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Huaxian Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above Huaxian Section change greatly and the non-point source pollution load proportions of total pollution load of COD decrease in the normal, rainy and wet period in turn.
Lateral mixing in the Mississippi River below the confluence with the Ohio River

USGS Publications Warehouse

Rathbun, R.E.; Rostad, C.E.

2004-01-01

Lateral dispersion coefficients for two dispersants were determined for three sections of the Mississippi River below the confluence with the Ohio River. The dispersants were the specific conductance and an industrial organic compound (trimethyltriazinetrione). Three models based on the stream tube concept were used, and lateral dispersion coefficients computed from these models were comparable. Coefficients for the two dispersants also were comparable. Lateral dispersion coefficients were consistent with expectations based on the characteristics of the river sections. Overall average values were 0.444 m2/s for a relatively straight section of river, 1.69 m2/s for a section containing two sharp bends, and 2.22 m2/s for a long section containing four sharp bends and several small islands. The lateral dispersion coefficients measured for the Mississippi River are consistent with literature data and a water discharge relation. Results of this study provide lateral dispersion coefficients for a water discharge not previously reported in the literature as well as new values for the Mississippi River.
A Review Of CryoSat-2/SIRAL Applications For The Monitoring Of River Water Levels

NASA Astrophysics Data System (ADS)

Bercher, Nicolas; Dinardo, Salvatore; Lucas, Bruno Manuel; Fleury, Sara; Calmant, Stephane; Femenias, Pierre; Boy, Francois; Picot, Nicolas; Benveniste, Jerome

2013-12-01

Regarding hydrology applications and particularly the monitoring of river water levels from space, the CryoSat- 2 ice mission has two main valuable characteristics: (1) its geodetic orbit and (2) the altimeter's SAR and SARin modes. The benefits of the geodetic orbit of the satellite have been illustrated in the frame of the ”20 years of progress in radar altimetry” symposium (Venice, 2012) [2]. It has been shown that, with such an orbit, the way river water level was monitored using conventional altimeters had to be revisited. In particular, using LRM mode only, CryoSat-2 allowed us to build spatio-temporal time series of the river water level, to map river's topography and eventually derive pseudo-time series and pseudo-profiles of the river. This paper focuses on the new ways to use altimetry for the monitoring of river water levels. SIRAL's (CryoSat-2 altimeter) SAR and SARin modes have the ability to deliver surface heights with an unprecedented along-track resolution of about 300 m. Moreover, using the SARin mode (involving the satellite's two antennas), the cross- track angle of the retracked echo is also available in routine. These two aspects of the SARin mode (high resolution and cross-track angle) make it a new tool to distinguish whether the retracked echo came from the sur- face of interest (e.g., a river) or any other reflective object nearby the surface of interest (e.g., another river section, lakes or temporary lake after flooding events or any other specular surfaces). We introduce the multiple benefits of using the intermediate multi-look matrix (also known as stack matrix), among them: (1) to refine and select among the multiple Doppler-beam waveforms before averaging and retracking them, and (2) to be able to study the surfaces response according to their view angle. Custom products processed at ESA (ESRIN) by Dinardo et al. [7], in the perspective of Sentinel-3, as well as official CryoSat-2 L1b and L2 products were used to illustrate these perspectives. The paper mainly introduces the potential new applications brought by SIRAL's SAR and SARin modes. Finally, combined with its really dense geodetic orbit, CryoSat-2 can be seen as a topography mission that paves the way toward the SWOT mission.
Geomorphic response of rivers to glacial retreat and increasing peak flows downstream from Mount Rainier, Washington

NASA Astrophysics Data System (ADS)

Czuba, J. A.; Barnas, C. R.; Magirl, C. S.; Voss, F. D.

2010-12-01

On Mount Rainier, Washington, the National Park Service has documented widespread aggradation of as much as 10 m since the early 20th century, of rivers draining the glaciated stratovolcano. This rapid sedimentation appears to be related to glacial retreat and also may be a function of the increased magnitude and timing of peak flows that mobilize and transport sediment. We are conducting an assessment of the Puget Lowland rivers that drain Mount Rainier, 25-100 km downstream from the park boundary, to document the geomorphic response of the downstream reaches given the widespread aggradation upstream. These downstream reaches provide critical aquatic habitat for spawning and rearing of several species of salmonids, including endangered Chinook salmon and steelhead. Fluvial sedimentation can have both deleterious and beneficial effects on aquatic habitat depending on sediment particle size, river slope and width, and river management. To date, our work shows sedimentation of as much as 2 m between 1984 and 2009 in these lowland rivers. Aggradation rates that were calculated by comparing channel change at 156 cross sections, ranged between 4.8 and 9.1 cm/yr in reaches where rivers exit the mountain front and enter the lowland. Analysis of streamflow-gaging station data from throughout the watersheds draining Mount Rainier show rapid incision and aggradation, suggesting pulses of coarse-grained bedload may be moving down the mountainous rivers as kinetic waves. Preliminary results, however, seem to indicate that the rivers in the Puget Lowland have not yet experienced significant widespread sedimentation directly related to glacial retreat. Estimating the time of arrival of mobilized alluvium is a critical need for resource managers given the potential effects of sedimentation on river flood-conveyance capacity, fish habitat, and estuarine wetlands.

33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Carolina Power & Light Company (CP&L) overhead power line crossing). (4) Passing Lane and Anchorage Basin... Buoy 56 (LL 30830) and approximately 590 feet downstream of the CP&L overhead power line crossing...
33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Carolina Power & Light Company (CP&L) overhead power line crossing). (4) Passing Lane and Anchorage Basin... Buoy 56 (LL 30830) and approximately 590 feet downstream of the CP&L overhead power line crossing...
33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Carolina Power & Light Company (CP&L) overhead power line crossing). (4) Passing Lane and Anchorage Basin... Buoy 56 (LL 30830) and approximately 590 feet downstream of the CP&L overhead power line crossing...
33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Carolina Power & Light Company (CP&L) overhead power line crossing). (4) Passing Lane and Anchorage Basin... Buoy 56 (LL 30830) and approximately 590 feet downstream of the CP&L overhead power line crossing...
33 CFR 165.540 - Regulated Navigation Area; Cape Fear River, Northeast Cape Fear River, Wilmington, North Carolina.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Carolina Power & Light Company (CP&L) overhead power line crossing). (4) Passing Lane and Anchorage Basin... Buoy 56 (LL 30830) and approximately 590 feet downstream of the CP&L overhead power line crossing...
Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Detail, Vertical Cross Bracing-End Detail - Cumberland Covered Bridge, Spanning Mississinewa River, Matthews, Grant County, IN
Phenomena and characteristics of barrier river reaches in the middle and lower Yangtze River, China

NASA Astrophysics Data System (ADS)

You, Xingying; Tang, Jinwu

2017-06-01

Alluvial river self-adjustment describes the mechanism whereby a river that was originally in an equilibrium state of sediment transport encounters some disturbance that destroys the balance and results in responses such as riverbed deformation. A systematic study of historical and recent aerial photographs and topographic maps in the Middle and Lower Reaches of the Yangtze River (MLYR) shows that river self-adjustment has the distinguishing feature of transferring from upstream to downstream, which may affect flood safety, waterway morphology, bank stability, and aquatic environmental safety over relatively long reaches downstream. As a result, it is necessary to take measures to control or block this transfer. Using the relationship of the occurrence time of channel adjustments between the upstream and downstream, 34 single-thread river reaches in the MLYR were classified into four types: corresponding, basically corresponding, basically not corresponding, not corresponding. The latter two types, because of their ability to prevent upstream channel adjustment from transferring downstream, are called barrier river reaches in this study. Statistics indicate that barrier river reaches are generally single thread and slightly curved, with a narrow and deep cross-sectional morphology, and without flow deflecting nodes in the upper and middle parts of reaches. Moreover, in the MLYR, barrier river reaches have a hydrogeometric coefficient of {<}{4}, a gradient {>}1.2‱, a silty clay content of the concave bank {>}{9.5}%, and a median diameter of the bed sediment {>}{0.158} mm. The barrier river reach mechanism lies in that can effectively centralise the planimetric position of the main stream from different upstream directions, meaning that no matter how the upper channel adjusts, the main stream shows little change, providing relatively stable inflow conditions for the lower reaches. Regarding river regulation, it is necessary to optimise the benefits of barrier river reaches; long river reaches without barrier properties should be systematically planned and regulated; drastic bank collapse and sandbar shrinking should be urgently controlled to prevent the loss of barrier effects.
Reconstructing the Santa Tecla flash flood in the Ondara River (Ebro Basin, NE Spain)

NASA Astrophysics Data System (ADS)

Balasch, J. C.; Tuset, J.; Ramos, M. C.; Martínez-Casasnovas, J. A.

2009-09-01

The Santa Tecla flood may be considered the most catastrophic rainfall event in the modern history of Catalonia (NE Iberian Peninsula), and one of the most important in the Western Mediterranean Basin. This event took place during the night between 22nd and 23rd September 1874, in which torrential convective rainfalls generated significant flash floods in most of the small streams in the southern half of Catalonia (i.e. Ondara, Corb, Francolí and Siurana catchments). More than 570 people died, 150 of which in the town of Tàrrega, by the Ondara River. Despite being one of the last huge floods of the pre-instrumental era and, consequently, without any precipitation or flow data, the event was reconstructed both hydraulically and hydrologically for the Ondara River at Tàrrega (150 km2). Thus, the maximum water level and the temporal evolution of the flood were obtained, respectively, from several epigraphic limnimarks found in Tàrrega and from the event description recorded in historical documents. Additionally, the information from local archaeological sites allowed the reconstruction of the fluvial section at Tàrrega at the end of the 19th century. Finally, some old cellars flooded during the event provided information about sediment concentration at the peak flow. The methodology put into practice for the event reconstruction had two stages. The first stage was the hydraulic modelling, which estimated the peak flow. The input data used were the maximum water level given by the limnimetric marks, a digital terrain model of the river bed shape, and the stream and floodplain roughness and channel slope (which were considered similar to the present ones, according to archaeological data). The hydraulic model used was the unidimensional HEC-RAS (USACE), applied in several cross sections of the Ondara River at Tàrrega. The second stage was the hydrological modelling. The objective of this stage was to derive the event hyetograph from the above calculated peak flow and the hydrologic response of the basin. This hydrologic behaviour, that is the relation between the hyetograph and the hydrograph, was estimated taking into account rainfall duration (6-8 hours according to historical documents), basin characteristics, soil type, soil land use and cover and the antecedent soil moisture, using SCS Curve Number method. After that, a transfer Synthetic Unitary Hydrograph function and a wave propagation method (Muskingum) were applied to describe the discharge evolution and the water routing into the stream channel. The software used in this stage was the HEC-HMS (USACE). The results of the hydraulic simulation at the Sant Agustí street cross section were the following: a) a maximum water depth of 6.16 m above the original river bed, b) a mean water velocity of about 2 m•s-1, c) a peak flow of 996 m3•s-1 (increased by 480 m3•s-1 from the Cercavins River downstream Tàrrega), and d) a specific peak discharge of the event of 6.6 m3•s-1•km-2, which exceeds the values of the 500-year return period floods compiled from the Ebro drainage basin systematic database. From the information obtained in the flooded cellars, the sediment concentration during the peak flow was estimated in 11.2% (in volume), characteristic of a hyperconcentrated flow. The water level reached in the abovepresented cross section is partly explained by the recently discovered Sant Agustí Bridge, buried until now in the river bed. The results of the hydrologic modelling were: a) a surface runoff total volume of 12 hm3, b) a runoff coefficient of about 35.5%, c) a lagtime of 2.5-3 hours, and d) if the previous soil humidity for the Curve Number method was low (situation I), a total rainfall of 225 mm with a peak intensity higher than 100 mm•h-1 is needed; if the previous soil humidity for the Curve Number method was medium (situation II), a total rainfall of 156 mm with a peak intensity of about 70 mm•h-1 occurs. Rainfall values for medium previous moisture condition (II) represent a 1000-year return period according to the regional systematic data.
Bathymetric and underwater video survey of Lower Granite Reservoir and vicinity, Washington and Idaho, 2009-10

USGS Publications Warehouse

Williams, Marshall L.; Fosness, Ryan L.; Weakland, Rhonda J.

2012-01-01

The U.S. Geological Survey conducted a bathymetric survey of the Lower Granite Reservoir, Washington, using a multibeam echosounder, and an underwater video mapping survey during autumn 2009 and winter 2010. The surveys were conducted as part of the U.S. Army Corps of Engineer's study on sediment deposition and control in the reservoir. The multibeam echosounder survey was performed in 1-mile increments between river mile (RM) 130 and 142 on the Snake River, and between RM 0 and 2 on the Clearwater River. The result of the survey is a digital elevation dataset in ASCII coordinate positioning data (easting, northing, and elevation) useful in rendering a 3×3-foot point grid showing bed elevation and reservoir geomorphology. The underwater video mapping survey was conducted from RM 107.73 to 141.78 on the Snake River and RM 0 to 1.66 on the Clearwater River, along 61 U.S. Army Corps of Engineers established cross sections, and dredge material deposit transects. More than 900 videos and 90 bank photographs were used to characterize the sediment facies and ground-truth the multibeam echosounder data. Combined, the surveys were used to create a surficial sediment facies map that displays type of substrate, level of embeddedness, and presence of silt.
Comparison of hyporheic flow and water quality in open and tree-covered banks downstream of Xin'an River dam, China

NASA Astrophysics Data System (ADS)

Liu, D.

2017-12-01

Plants, especially trees, in the riparian zone may have a significant impact on the flow rate, temperature and chemical properties of groundwater. A field study was conducted in the downstream bank of the Xin'an River dam, Zhejiang, China. In the field, two areas of about 20 meters apart were chosen, of which one was a open place and the other was covered with many orange trees. Comparison of hyporheic flow and water quality in the open and tree-covered banks were made by monitoring the water level, water temperature, water chemistry (March, 2015) along the cross sections perpendicular to the river. The analyses indicated that water level around the trees was relatively low in the day and high in the evening, thus changed the direction and magnitude of the natural groundwater flow velocity, totally strengthened the hyporheic exchange between the groundwater and river. The trees also changed the temperature distribution of the natural river bank, and induced the wider infiltration range of the low-temperature water. The temperature around the trees was relatively low in the day, yet it was high in the evening. Dissolved oxygen (DO) and electricity conductivity (EC) around the trees were significantly increased, yet the pH was almost unaffected.
Modeling hydraulic and sediment transport processes in white sturgeon spawning habitat on the Kootenai River, Idaho

USGS Publications Warehouse

McDonald, Richard R.; Nelson, Jonathan M.; Vaughn Paragamian,; Barton, Gary J.

2017-01-01

The Kootenai River white sturgeon currently spawn (2005) in an 18-kilometer reach of the Kootenai River, Idaho. Since completion of Libby Dam upstream from the spawning reach, there has been only one successful year of recruitment of juvenile fish. Where successful in other rivers, white sturgeon spawn over clean coarse material of gravel size or larger. The channel substrate in the current spawning reach is composed primarily of sand and some buried gravel; within a few kilometers upstream there is clean gravel. We used a 2-dimensional flow and sediment-transport model and the measured locations of sturgeon spawning from 1994-2002 to gain insight into the paradox between the current spawning location and the absence of suitable substrate. Spatial correlations between spawning locations and the model simulations of velocity and depth indicate the white sturgeon tend to select regions of highest velocity and depth within any river cross-section to spawn. These regions of high velocity and depth are independent of pre- or post-dam flow conditions. A simple sediment-transport simulation suggests that high discharge and relatively long duration flow associated with pre-dam flow events might be sufficient to scour the sandy substrate and expose existing lenses of gravel and cobble as lag deposits in the current spawning reach.
A model to predict the evolution of a gravel bed river under an imposed cyclic hydrograph and its application to the Trinity River

NASA Astrophysics Data System (ADS)

Viparelli, Enrica; Gaeuman, David; Wilcock, Peter; Parker, Gary

2011-02-01

Major changes in the morphology of the Trinity River in California, such as narrowing of the cross section and sedimentation of fine sediment in pools, occurred after the closure of a system of dams. These changes caused a dramatic reduction in the salmonid population and a resulting decline of the fishery. Gravel augmentation, regulated flood releases, and mechanical channel rehabilitation are currently being implemented to help restore the aquatic habitat of the river. The present paper describes a tool, named the Spawning Gravel Refresher, for designing and predicting the effects of gravel augmentation in gravel bed rivers. The tool assumes an imposed, cycled hydrograph. The model is calibrated and applied to the regulated reach of the Trinity River in four steps: (1) zeroing runs to reproduce conditions of mobile bed equilibrium as best can be estimated for the predam Trinity River, (2) runs to compare the predictions with the results of previous studies, (3) runs at an engineering time scale to reproduce the effects of the dams, and (4) runs to design gravel augmentation schemes. In the fourth group of runs, the combined effects of engineered flood flow releases and gravel augmentation are predicted. At an engineering time scale, the model indicates that the fraction of fine sediment in the surface layer and in the topmost part of the substrate should decrease when subjected to these two restoration measures, with a consequent improvement of the quality of the spawning gravel.
Monitoring and research to describe geomorphic effects of the 2011 controlled flood on the Green River in the Canyon of Lodore, Dinosaur National Monument, Colorado and Utah

USGS Publications Warehouse

Mueller, Erich R.; Grams, Paul E.; Schmidt, John C.; Hazel, Joseph E.; Kaplinski, Matt; Alexander, Jason A.; Kohl, Keith

2014-01-01

In 2011, a large magnitude flow release from Flaming Gorge Reservoir, Wyoming and Utah, occurred in response to high snowpack in the middle Rocky Mountains. This was the third highest recorded discharge along the Green River downstream of Flaming Gorge Dam, Utah, since its initial closure in November 1962 and motivated a research effort to document effects of these flows on channel morphology and sedimentology at four long-term monitoring sites within the Canyon of Lodore in Dinosaur National Monument, Colorado and Utah. Data collected in September 2011 included raft-based bathymetric surveys, ground-based surveys of banks, channel cross sections and vegetation-plot locations, sand-bar stratigraphy, and painted rock recovery on gravel bars. As part of this surveying effort, Global Navigation Satellite System (GNSS) data were collected at benchmarks on the canyon rim and along the river corridor to establish a high-resolution survey control network. This survey control network allows for the collection of repeatable spatial and elevation data necessary for high accuracy geomorphic change detection. Nearly 10,000 ground survey points and more than 20,000 bathymetric points (at 1-meter resolution) were collected over a 5-day field campaign, allowing for the construction of reach-scale digital elevation models (DEMs). Additionally, we evaluated long-term geomorphic change at these sites using repeat topographic surveys of eight monumented cross sections at each of the four sites. Analysis of DEMs and channel cross sections show a spatially variable pattern of erosion and deposition, both within and between reaches. As much as 5 meters of scour occurred in pools downstream from flow constrictions, especially in channel segments where gravel bars were absent. By contrast, some channel cross sections were stable during the 2011 floods, and have shown almost no change in over a decade of monitoring. Partial mobility of gravel bars occurred, and although in some locations vegetation such as tamarisk (Tamarix ramosissima) was damaged, wholesale bed motion necessary to fully clear these surfaces was not evident. In flow recirculation zones, eddy sandbars aggraded one meter or more, increasing the area of bars exposed during typical dam operations. Yet overall, the 2011 flood resulted in a decrease in reach-scale sand storage because bed degradation exceeded bar deposition. The 2011 response is consistent with that of a similar event in 1999, which was followed by sand-bar erosion and sediment accumulation on the bed during subsequent years of normal dam operational flows. Although the 1999 and 2011 floods were exceptional in the post-dam system, they did not exceed the pre-dam 2-year flood, isolating their effects to the modern active channel with minor erosion or reworking of pre-dam deposits stabilized through vegetation encroachment.
Use of radars to monitor stream discharge by noncontact methods

USGS Publications Warehouse

Costa, J.E.; Cheng, R.T.; Haeni, F.P.; Melcher, N.; Spicer, K.R.; Hayes, E.; Plant, W.; Hayes, K.; Teague, C.; Barrick, D.

2006-01-01

Conventional measurements of river flows are costly, time‐consuming, and frequently dangerous. This report evaluates the use of a continuous wave microwave radar, a monostatic UHF Doppler radar, a pulsed Doppler microwave radar, and a ground‐penetrating radar to measure river flows continuously over long periods and without touching the water with any instruments. The experiments duplicate the flow records from conventional stream gauging stations on the San Joaquin River in California and the Cowlitz River in Washington. The purpose of the experiments was to directly measure the parameters necessary to compute flow: surface velocity (converted to mean velocity) and cross‐sectional area, thereby avoiding the uncertainty, complexity, and cost of maintaining rating curves. River channel cross sections were measured by ground‐penetrating radar suspended above the river. River surface water velocity was obtained by Bragg scattering of microwave and UHF Doppler radars, and the surface velocity data were converted to mean velocity on the basis of detailed velocity profiles measured by current meters and hydroacoustic instruments. Experiments using these radars to acquire a continuous record of flow were conducted for 4 weeks on the San Joaquin River and for 16 weeks on the Cowlitz River. At the San Joaquin River the radar noncontact measurements produced discharges more than 20% higher than the other independent measurements in the early part of the experiment. After the first 3 days, the noncontact radar discharge measurements were within 5% of the rating values. On the Cowlitz River at Castle Rock, correlation coefficients between the USGS stream gauging station rating curve discharge and discharge computed from three different Doppler radar systems and GPR data over the 16 week experiment were 0.883, 0.969, and 0.992. Noncontact radar results were within a few percent of discharge values obtained by gauging station, current meter, and hydroacoustic methods. Time series of surface velocity obtained by different radars in the Cowlitz River experiment also show small‐amplitude pulsations not found in stage records that reflect tidal energy at the gauging station. Noncontact discharge measurements made during a flood on 30 January 2004 agreed with the rated discharge to within 5%. Measurement at both field sites confirm that lognormal velocity profiles exist for a wide range of flows in these rivers, and mean velocity is approximately 0.85 times measured surface velocity. Noncontact methods of flow measurement appear to (1) be as accurate as conventional methods, (2) obtain data when standard contact methods are dangerous or cannot be obtained, and (3) provide insight into flow dynamics not available from detailed stage records alone.
Geologic setting of the low-level burial grounds

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lindsey, K.A.; Jaeger, G.K.; Slate, J.L.

1994-10-13

This report describes the regional and site specific geology of the Hanford Sites low-level burial grounds in the 200 East and West Areas. The report incorporates data from boreholes across the entire 200 Areas, integrating the geology of this area into a single framework. Geologic cross-sections, isopach maps, and structure contour maps of all major geological units from the top of the Columbia River Basalt Group to the surface are included. The physical properties and characteristics of the major suprabasalt sedimentary units also are discussed.
29 CFR 1917.126 - River banks.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 7 2011-07-01 2011-07-01 false River banks. 1917.126 Section 1917.126 Labor Regulations...) MARINE TERMINALS Terminal Facilities § 1917.126 River banks. (a) This section applies to temporary installations or temporary operations near a river bank. (b) Where working surfaces at river banks slope so...
29 CFR 1917.126 - River banks.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) MARINE TERMINALS Terminal Facilities § 1917.126 River banks. (a) This section applies to temporary installations or temporary operations near a river bank. (b) Where working surfaces at river banks slope so... 29 Labor 7 2010-07-01 2010-07-01 false River banks. 1917.126 Section 1917.126 Labor Regulations...
Traditional medicine used in childbirth and for childhood diarrhoea in Nigeria's Cross River State: interviews with traditional practitioners and a statewide cross-sectional study

PubMed Central

Sarmiento, Iván; Zuluaga, Germán; Andersson, Neil

2016-01-01

Objectives Examine factors associated with use of traditional medicine during childbirth and in management of childhood diarrhoea. Design Cross-sectional cluster survey, household interviews in a stratified last stage random sample of 90 census enumeration areas; unstructured interviews with traditional doctors. Setting Oil-rich Cross River State in south-eastern Nigeria has 3.5 million residents, most of whom depend on a subsistence agriculture economy. Participants 8089 women aged 15–49 years in 7685 households reported on the health of 11 305 children aged 0–36 months in July–August 2011. Primary and secondary outcome measures Traditional medicine used at childbirth and for management of childhood diarrhoea; covariates included access to Western medicine and education, economic conditions, engagement with the modern state and family relations. Cluster-adjusted analysis relied on the Mantel-Haenszel procedure and Mantel extension. Results 24.1% (1371/5686) of women reported using traditional medicine at childbirth; these women had less education, accessed antenatal care less, experienced more family violence and were less likely to have birth certificates for their children. 11.3% (615/5425) of young children with diarrhoea were taken to traditional medical practitioners; these children were less likely to receive BCG, to have birth certificates, to live in households with a more educated head, or to use fuel other than charcoal for cooking. Education showed a gradient with decreasing use of traditional medicine for childbirth (χ2 135.2) and for childhood diarrhoea (χ2 77.2). Conclusions Use of traditional medicine is associated with several factors related to cultural transition and to health status, with formal education playing a prominent role. Any assessment of the effectiveness of traditional medicine should anticipate confounding by these factors, which are widely recognised to affect health in their own right. PMID:27094939
Traditional medicine used in childbirth and for childhood diarrhoea in Nigeria's Cross River State: interviews with traditional practitioners and a statewide cross-sectional study.

PubMed

Sarmiento, Iván; Zuluaga, Germán; Andersson, Neil

2016-04-19

Examine factors associated with use of traditional medicine during childbirth and in management of childhood diarrhoea. Cross-sectional cluster survey, household interviews in a stratified last stage random sample of 90 census enumeration areas; unstructured interviews with traditional doctors. Oil-rich Cross River State in south-eastern Nigeria has 3.5 million residents, most of whom depend on a subsistence agriculture economy. 8089 women aged 15-49 years in 7685 households reported on the health of 11,305 children aged 0-36 months in July-August 2011. Traditional medicine used at childbirth and for management of childhood diarrhoea; covariates included access to Western medicine and education, economic conditions, engagement with the modern state and family relations. Cluster-adjusted analysis relied on the Mantel-Haenszel procedure and Mantel extension. 24.1% (1371/5686) of women reported using traditional medicine at childbirth; these women had less education, accessed antenatal care less, experienced more family violence and were less likely to have birth certificates for their children. 11.3% (615/5425) of young children with diarrhoea were taken to traditional medical practitioners; these children were less likely to receive BCG, to have birth certificates, to live in households with a more educated head, or to use fuel other than charcoal for cooking. Education showed a gradient with decreasing use of traditional medicine for childbirth (χ(2) 135.2) and for childhood diarrhoea (χ(2) 77.2). Use of traditional medicine is associated with several factors related to cultural transition and to health status, with formal education playing a prominent role. Any assessment of the effectiveness of traditional medicine should anticipate confounding by these factors, which are widely recognised to affect health in their own right. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Modeling the influence of river rehabilitation scenarios on bed material sediment flux in a large river over decadal timescales

USGS Publications Warehouse

Singer, Michael B.; Dunne, Thomas

2006-01-01

A stochastic flood generator and calibrated sediment transport formulae were used to assess the decadal impact of major river rehabilitation strategies on two fraction bed material sediment flux and net storage, first‐order indicators of aquatic riverine habitat, in a large river system. Model boundary conditions were modified to reflect the implementation of three major river rehabilitation strategies being considered in the Sacramento River Valley: gravel augmentation, setting back of levees, and flow alteration. Fifty 30‐year model simulations were used to compute probabilities of the response in sediment flux and net storage to these strategies. Total annual average bed material sediment flux estimates were made at six gauged river cross sections, and ∼60 km reach‐scale sediment budgets were evaluated between them. Gravel augmentation to improve spawning habitat induced gravel accumulation locally and/or downstream, depending on the added mixture. Levee setbacks to recreate the river corridor reduced flow stages for most flows and hence lowered sediment flux. Flow alteration to mimic natural flow regimes systematically decreased total annual average flux, suggesting that high‐magnitude low‐frequency transport events do not affect long‐term trends in bed material flux. The results indicate that each rehabilitation strategy reduces sediment transport in its target reaches and modulates imbalances in total annual bed material sediment budgets at the reach scale. Additional risk analysis is necessary to identify extreme conditions associated with variable hydrology that could affect rehabilitation over decades. Sensitivity analysis suggests that sorting of bed material sediment is the most important determinant of modeled transport and storage patterns.

Passive optical remote sensing of Congo River bathymetry using Landsat

NASA Astrophysics Data System (ADS)

Ache Rocha Lopes, V.; Trigg, M. A.; O'Loughlin, F.; Laraque, A.

2014-12-01

While there have been notable advances in deriving river characteristics such as width, using satellite remote sensing datasets, deriving river bathymetry remains a significant challenge. Bathymetry is fundamental to hydrodynamic modelling of river systems and being able to estimate this parameter remotely would be of great benefit, especially when attempting to model hard to access areas where the collection of field data is difficult. One such region is the Congo Basin, where due to past political instability and large scale there are few studies that characterise river bathymetry. In this study we test whether it is possible to use passive optical remote sensing to estimate the depth of the Congo River using Landsat 8 imagery in the region around Malebo Pool, located just upstream of the Kinshasa gauging station. Methods of estimating bathymetry using remotely sensed datasets have been used extensively for coastal regions and now more recently have been demonstrated as feasible for optically shallow rivers. Previous river bathymetry studies have focused on shallow rivers and have generally used aerial imagery with a finer spatial resolution than Landsat. While the Congo River has relatively low suspended sediment concentration values the application of passive bathymetry estimation to a river of this scale has not been attempted before. Three different analysis methods are tested in this study: 1) a single band algorithm; 2) a log ratio method; and 3) a linear transform method. All three methods require depth data for calibration and in this study area bathymetry measurements are available for three cross-sections resulting in approximately 300 in-situ measurements of depth, which are used in the calibration and validation. The performance of each method is assessed, allowing the feasibility of passive depth measurement in the Congo River to be determined. Considering the scarcity of in-situ bathymetry measurements on the Congo River, even an approximate estimate of depths from these methods will be of considerable value in its hydraulic characterisation.
Balancing hydropower production and river bed incision in operating a run-of-river hydropower scheme along the River Po

NASA Astrophysics Data System (ADS)

Denaro, Simona; Dinh, Quang; Bizzi, Simone; Bernardi, Dario; Pavan, Sara; Castelletti, Andrea; Schippa, Leonardo; Soncini-Sessa, Rodolfo

2013-04-01

Water management through dams and reservoirs is worldwide necessary to support key human-related activities ranging from hydropower production to water allocation, and flood risk mitigation. Reservoir operations are commonly planned in order to maximize these objectives. However reservoirs strongly influence river geomorphic processes causing sediment deficit downstream, altering the flow regime, leading, often, to process of river bed incision: for instance the variations of river cross sections over few years can notably affect hydropower production, flood mitigation, water supply strategies and eco-hydrological processes of the freshwater ecosystem. The river Po (a major Italian river) has experienced severe bed incision in the last decades. For this reason infrastructure stability has been negatively affected, and capacity to derive water decreased, navigation, fishing and tourism are suffering economic damages, not to mention the impact on the environment. Our case study analyzes the management of Isola Serafini hydropower plant located on the main Po river course. The plant has a major impact to the geomorphic river processes downstream, affecting sediment supply, connectivity (stopping sediment upstream the dam) and transport capacity (altering the flow regime). Current operation policy aims at maximizing hydropower production neglecting the effects in term of geomorphic processes. A new improved policy should also consider controlling downstream river bed incision. The aim of this research is to find suitable modeling framework to identify an operating policy for Isola Serafini reservoir able to provide an optimal trade-off between these two conflicting objectives: hydropower production and river bed incision downstream. A multi-objective simulation-based optimization framework is adopted. The operating policy is parameterized as a piecewise linear function and the parameters optimized using an interactive response surface approach. Global and local response surface are comparatively assessed. Preliminary results show that a range of potentially interesting trade-off policies exist able to better control river bed incision downstream without significantly decreasing hydropower production.
Rainfall-Runoff Parameters Uncertainity

NASA Astrophysics Data System (ADS)

Heidari, A.; Saghafian, B.; Maknoon, R.

2003-04-01

Karkheh river basin, located in southwest of Iran, drains an area of over 40000 km2 and is considered a flood active basin. A flood forecasting system is under development for the basin, which consists of a rainfall-runoff model, a river routing model, a reservior simulation model, and a real time data gathering and processing module. SCS, Clark synthetic unit hydrograph, and Modclark methods are the main subbasin rainfall-runoff transformation options included in the rainfall-runoff model. Infiltration schemes, such as exponentioal and SCS-CN methods, account for infiltration losses. Simulation of snow melt is based on degree day approach. River flood routing is performed by FLDWAV model based on one-dimensional full dynamic equation. Calibration and validation of the rainfall-runoff model on Karkheh subbasins are ongoing while the river routing model awaits cross section surveys.Real time hydrometeological data are collected by a telemetry network. The telemetry network is equipped with automatic sensors and INMARSAT-C comunication system. A geographic information system (GIS) stores and manages the spatial data while a database holds the hydroclimatological historical and updated time series. Rainfall runoff parameters uncertainty is analyzed by Monte Carlo and GLUE approaches.
Secondary flow structures in large rivers

NASA Astrophysics Data System (ADS)

Chauvet, H.; Devauchelle, O.; Metivier, F.; Limare, A.; Lajeunesse, E.

2012-04-01

Measuring the velocity field in large rivers remains a challenge, even with recent measurement techniques such as Acoustic Doppler Current Profiler (ADCP). Indeed, due to the diverging angle between its ultrasonic beams, an ADCP cannot detect small-scale flow structures. However, when the measurements are limited to a single location for a sufficient period of time, averaging can reveal large, stationary flow structures. Here we present velocity measurements in a straight reach of the Seine river in Paris, France, where the cross-section is close to rectangular. The transverse modulation of the streamwise velocity indicates secondary flow cells, which seem to occupy the entire width of the river. This observation is reminiscent of the longitudinal vortices observed in laboratory experiments (e.g. Blanckaert et al., Advances in Water Resources, 2010, 33, 1062-1074). Although the physical origin of these secondary structures remains unclear, their measured velocity is sufficient to significantly impact the distribution of streamwise momentum. We propose a model for the transverse profile of the depth-averaged velocity based on a crude representation of the longitudinal vortices, with a single free parameter. Preliminary results are in good agreement with field measurements. This model also provides an estimate for the bank shear stress, which controls bank erosion.
Streamflow and sediment data collected to determine the effects of a controlled flood in March and April 1996 on the Colorado River between Lees Ferry and Diamond Creek, Arizona

USGS Publications Warehouse

Konieczki, Alice D.; Graf, Julia B.; Carpenter, Michael C.

1997-01-01

An 8-day period of planned release of water at 1,275 cubic meters per second from Glen Canyon Dam in March and April 1996 provided an opportunity to collect data on river stage, streamflow, water chemistry, and sediment transport at discharges above powerplant releases. The U.S. Geological Survey collected data at five streamflow-gaging stations on the mainstem of the Colorado River and four on tributaries during the controlled flood. River-stage data were collected at an additional 29 locations, and suspended-sediment data were collected at 4 of the 5 mainstem streamflow-gaging stations. In addition, measurements of reach-average flow velocity were made using a dye tracer, and water-surface slope was measured in reaches adjacent to three of the streamflow-gaging stations. Sand-storage changes caused by the controlled flood were documented by measuring bed elevation of the channel at cross sections before and after the controlled releases at the network of 120 monumented locations. This report presents selected data in tabular and graphical form. The data presented in the report are available in electronic form.
Continuous measurements of bedload transport rates in a small glacial river catchment in the summer season (Spitsbergen)

NASA Astrophysics Data System (ADS)

Kociuba, Waldemar; Janicki, Grzegorz

2014-05-01

The study on bedload transport was conducted on the gravel-bed Scott River catchment with a glacial alimentation regime, located in the NW part of the Wedel Jarlsberg Land (Spitsbergen) with subpolar climatic conditions. In the melt season of 2010, bedload transport rate was continuously monitored at 24-hour intervals by means of four River Bedload Trap devices aligned across the width of the channel. The maximum bedload transport rate varied strongly at portions of the cross section from 16 to 152 kg m- 1 d- 1 in cross-profile I (c-p I) and 4 to 125 kg m- 1 d- 1 in cross-profile II (c-p II). The maximum channel-mean bedload transport rate (qa) amounted to 54 kg m- 1 d- 1 (c-p I) and 35 kg m- 1 d- 1 (c-p II). Mean daily bedload discharge (Qb) was estimated at a level of 97 kg day- 1 (c-p I) and 35 kg m- 1 d- 1 (c-p II), and the total bedload yield was determined at approx. 4345 kg in the measurement period (2086 kg — c-p I; 2203 kg — c-p II from 13.07 to 10.08). The analysis of the relationship between channel-mean bedload transport rate and water velocity or shear stress revealed a significant value of the correlation coefficient (R2 = 0.6). Discharge and rate of bedload transport were dependent on the weather and number of days with flood discharge. Approx. 58% of the entire discharged bedload was transported during 3 violent ablation-precipitation floods. Bedload grain size distribution was right-skewed and showed moderate sorting.
76 FR 63858 - Drawbridge Operation Regulation; Trent River, New Bern, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

... River Bridge Runs. This deviation allows the bridge to remain in the closed position to ensure safe..., Docket Operations, telephone 202-366-9826. SUPPLEMENTARY INFORMATION: The Neuse River Bridge Run... River, mile 0.0, at New Bern, NC. The route of the three Neuse River Bridge Run races cross the bridge...
Simulation of flow and sediment mobility using a multidimensional flow model for the White Sturgeon critical-habitat reach, Kootenai River near Bonners Ferry, Idaho

USGS Publications Warehouse

Barton, Gary J.; McDonald, Richard R.; Nelson, Jonathan M.; Dinehart, Randal L.

2005-01-01

In 1994, the Kootenai River white sturgeon (Acipenser transmontanus) was listed as an Endangered Species as a direct result of two related observations. First, biologists observed that the white sturgeon population in the Kootenai River was declining. Second, they observed a decline in recruitment of juvenile sturgeon beginning in the 1950s with an almost total absence of recruitment since 1974, following the closure of Libby Dam in 1972. This second observation was attributed to changes in spawning and (or) rearing habitat resulting from alterations in the physical habitat, including flow regime, sediment-transport regime, and bed morphology of the river. The Kootenai River White Sturgeon Recovery Team was established to find and implement ways to improve spawning and rearing habitat used by white sturgeon. They identified the need to develop and apply a multidimensional flow model to certain reaches of the river to quantify physical habitat in a spatially distributed manner. The U.S. Geological Survey has addressed these needs by developing, calibrating, and validating a multidimensional flow model used to simulate streamflow and sediment mobility in the white sturgeon critical-habitat reach of the Kootenai River. This report describes the model and limitations, presents the results of a few simple simulations, and demonstrates how the model can be used to link physical characteristics of streamflow to biological or other habitat data. This study was conducted in cooperation with the Kootenai Tribe of Idaho along a 23-kilometer reach of the Kootenai River, including the white sturgeon spawning reach near Bonners Ferry, Idaho that is about 108 to 131 kilometers below Libby Dam. U.S. Geological Survey's MultiDimensional Surface-Water Modeling System was used to construct a flow model for the critical-habitat reach of the Kootenai River white sturgeon, between river kilometers 228.4 and 245.9. Given streamflow, bed roughness, and downstream water-surface elevation, the model computes the velocity field, water-surface elevations, and boundary shear stress throughout the modeled reach. The 17.5 kilometer model reach was subdivided into two segments on the basis of predominant grain size: a straight reach with a sand, gravel, and cobble substrate located between the upstream model boundary at river kilometer 245.9 and the upstream end of Ambush Rock at river kilometer 244.6, and a meandering reach with a predominately sand substrate located between upstream end of Ambush Rock and the downstream model boundary at river kilometer 228.4. Model cell size in the x and y (horizontal) dimensions is 5 meters by 5 meters along the computational grid centerline with 15 nodes in the z (vertical) dimension. The model was calibrated to historical streamflows evenly distributed between 141.6 and 2,548.9 cubic meters per second. The model was validated by comparing simulated velocities with velocities measured at 15 cross sections during steady streamflow. These 15 cross sections were each measured multiple (7-13) times to obtain velocities suitable for comparison to the model results. Comparison of modeled and measured velocities suggests that the model does a good job of reproducing flow patterns in the river, although some discrepancies were noted. The model was used to simulate water-surface elevation, depth, velocity, bed shear stress, and sediment mobility for Kootenai River streamflows of 170, 566, 1,130, 1,700, and 2,270 cubic meters per second (6,000, 20,000, 40,000, 60,000, and 80,000 cubic feet per second). The three lowest streamflow simulations represent a range of typical river conditions before and since the construction of Libby Dam, and the highest streamflow simulation (2,270 cubic meters per second) is approximately equal to the annual median peak streamflow prior to emplacement of Libby Dam in 1972. Streamflow greater than 566 cubic meters per second were incrementally increased by 570 cubic meters per second. For each
Structure and petroleum potential of the continental margin between Cross Sound and Icy Bay, northern Gulf of Alaska

USGS Publications Warehouse

Bruns, T.R.

1982-01-01

Major structural features of the Yakutat segment, the segment of the continental margin between Cross Sound and Icy Bay, northern Gulf of Alaska, are delineated by multichannel seismic reflection data. A large structural high is centered on Fairweather Ground and lies generally at the edge of the shelf from Cross Sound to west of the Alsek Valley. A basement uplift, the Dangerous River zone, along which the seismic acoustic basement shallows by up to two kilometers, extends north from the western edge of Fairweather Ground towards the mouth of the Dangerous River. The Dangerous River zone separates the Yakutat segment into two distinct subbasins. The eastern subbasin has a maximum sediment thickness of about 4 km, and the axis of the basin is near and parallel to the coast. Strata in this basin are largely of late Cenozoic age (Neogene and Quaternary) and approximately correlate with the onshore Yakataga Formation. The western subbasin has a maximum of at least 9 km of sediment, comprised of a thick (greater than 4.5 km) Paleogene section overlain by late Cenozoic strata. The Paleogene section is truncated along the Dangerous River zone by a combination of erosion, faulting, and onlap onto the acoustic basement. Within the western subbasin, the late Cenozoic basin axis is near and parallel to the coast, but the Paleogene basin axis appears to trend in a northwest direction diagonally across the shelf. Sedimentary strata throughout the Yakutat shelf show regional subsidence and only minor deformation except in the vicinity of the Fairweather Ground structural high, near and along the Dangerous River zone, and at the shoreline near Lituya Bay. Seismic data across the continental slope and adjacent deep ocean show truncation at the continental slope of Paleogene strata, the presence of a thick (to 6 km) undeformed or mildly deformed abyssal sedimentary section at the base of the slope that in part onlaps the slope, and a relatively narrow zone along the slope or at the base of the slope where faulting may have occurred. Observed deformation at the base of the slope is primarily related to the late Cenozoic uplift of Fairweather Ground, and to Quaternary folding perpendicular to the Pacific-North America relative convergence vector. No accretionary section or major deformation is observed along the continental slope. The absence of these features suggests that no major subduction of the Pacific plate beneath the Yakutat margin has occurred during the late Cenozoic. However, transform faulting along the base of the slope has occurred, because probable Oligocene oceanic basement is juxtaposed against Mesozoic and Paleogene sedimentary strata of the Yakutat slope. This juxtaposition most likely occurred during late Oligocene and Miocene time. During much of the late Cenozoic, and especially during Pliocene-Pleistocene time, the Yakutat segment has apparently been moving northward with the Pacific plate. Dredge samples from the continental slope recovered potential hydrocarbon source and reservoir rocks from the Paleogene sedimentary sequence. Most of the organic matter from these samples is immature to marginally mature. Lopatin calculations suggest that rocks beneath the shelf are likely to be thermally mature at a depth of 4 to 5 km and deeper. In general, the strata at these depths are largely of Paleogene age. Thus, the Paleogene strata may have significant resource potential if source and reservoir rocks similar to those dredged at the slope are present below the shelf. The Paleogene strata are contained primarily within the western subbasin; strata in the east subbasin appear to have little resource potential. Structural traps are apparently present in parts of the basin near and along the Dangerous River zone. These traps are in an updip position from potentially mature strata of the western subbasin, and may hold commercial accumulations of hydrocarbons, if sufficient hydrocarbon generation and migration has occurred
Inorganic and organic carbon spatial variability in the Congo River during high waters (December 2013)

NASA Astrophysics Data System (ADS)

Borges, Alberto V.; Bouillon, Steven; Teodoru, Cristian; Leporcq, Bruno; Descy, Jean-Pïerre; Darchambeau, François

2014-05-01

Rivers are important components of the global carbon cycle, as they transport terrestrial organic matter from the land to the sea, and emit CO2 to the atmosphere. In particular, tropical systems that account for 60% of global freshwater discharge to the oceans. In contrast with south American rivers, very little information is available for African rivers on their carbon flows and stocks, in particular the Congo river, the second largest river in the World in terms of freshwater discharge (1457 km3 yr-1) and in terms of drainage basin (3.75 106 km2) located the second largest tropical forest in the World. Here, we report a data-set of continuous (every minute) records of the partial pressure of CO2 (pCO2) (total of 10,000 records), and discrete samples of particulate (POC) and dissolved (DOC) organic carbon (total of 75 samples) in the mainstem and major tributaries of the Congo river, along the 1700 km stretch from Kisangani to Kinshasa (total river length = 4374 km), during the high water period (December 2013). The pCO2 dynamic range was high ranging from minimum values of 2000 ppm in white waters tributaries (higher turbidity, conductivity and O2, lower DOC), up to maximal values of 18,000 ppm in blackwaters tributaries (lower turbidity, conductivity and O2, higher DOC). In the mainstem, very strong horizontal (cross-section) gradients were imposed by the presence of blackwaters close to the riverbanks and the presence of whitewaters in the middle of the river. In the mainstem, a distinct horizontal (longitudinal) pattern was observed with pCO2 increasing, and conductivity and turbidity decreasing downstream.
Synthetic River Valleys

NASA Astrophysics Data System (ADS)

Brown, R.; Pasternack, G. B.

2011-12-01

The description of fluvial form has evolved from anecdotal descriptions to artistic renderings to 2D plots of cross section or longitudinal profiles and more recently 3D digital models. Synthetic river valleys, artificial 3D topographic models of river topography, have a plethora of potential applications in fluvial geomorphology, and the earth sciences in general, as well as in computer science and ecology. Synthetic river channels have existed implicitly since approximately the 1970s and can be simulated from a variety of approaches spanning the artistic and numerical. An objective method of synthesizing 3D stream topography based on reach scale attributes would be valuable for sizing 3D flumes in the physical and numerical realms, as initial input topography for morphodynamic models, stream restoration design, historical reconstruction, and mechanistic testing of interactions of channel geometric elements. Quite simply - simulation of synthetic channel geometry of prescribed conditions can allow systematic evaluation of the dominant relationships between river flow and geometry. A new model, the control curve method, is presented that uses hierarchically scaled parametric curves in over-lapping 2D planes to create synthetic river valleys. The approach is able to simulate 3D stream geometry from paired 2D descriptions and can allow experimental insight into form-process relationships in addition to visualizing past measurements of channel form that are limited to two dimension descriptions. Results are presented that illustrate the models ability to simulate fluvial topography representative of real world rivers as well as how channel geometric elements can be adjusted. The testing of synthetic river valleys would open up a wealth of knowledge as to why some 3D attributes of river channels are more prevalent than others as well as bridging the gap between the 2D descriptions that have dominated fluvial geomorphology the past century and modern, more complete, 3D treatments.
Variation in flow and suspended sediment transport in a montane river affected by hydropeaking and instream mining

NASA Astrophysics Data System (ADS)

Béjar, M.; Vericat, D.; Batalla, R. J.; Gibbins, C. N.

2018-06-01

The temporal and spatial variability of water and sediment loads of rivers is controlled by a suite of factors whose individual effects are often difficult to disentangle. While land use changes and localised human activities such as instream mining and hydropeaking alter water and sediment transfer, tributaries naturally contribute to discharge and sediment load of mainstem rivers, and so may help compensate upstream anthropogenic factors. The work presented here aimed to assess water and the sediment transfer in a river reach affected by gravel extraction and hydropeaking, set against a backdrop of changes to the supply of water and sediment from tributaries. Discharge and suspended sediment transport were monitored during two average hydrological years at three cross-sections along a 10-km reach of the upper River Cinca, in the Southern Pyrenees. Water and sediment loads differed substantially between the reaches. The upper reach showed a largely torrential discharge regime, controlled mainly by floods, and had high but variable water and sediment loads. The middle reach was influenced markedly by hydropeaking and tributary inflows, which increased its annual water yield four-fold. Suspended sediment load in this reach increased by only 25% compared to upstream, indicating that dilution predominated. In the lowermost section, while discharge remained largely unaltered, sediment load increased appreciably as a result of changes to sediment availability from instream mining and inputs from tributaries. At the reach scale, snowmelt and summer and autumn thunderstorms were responsible for most of the water yield, while flood flows determined the magnitude and transport of the sediment load. The study highlights that a combination of natural and human factors control the spatial and temporal transfer of water and sediment in river channels and that, depending on their geographic location and effect-size, can result in marked variability even over short downstream distances.
1. Photocopy of engineering drawing (original in the Office of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Photocopy of engineering drawing (original in the Office of the Cuyahoga County Engineer)--1907 NORTH ROCKY RIVER BRIDGE--PROPOSED DESIGN--REINFORCED CONCRETE: AN ALTERNATIVE DESIGN FOR THE DETROIT AVENUE CROSSING - Rocky River Bridge, Spanning Beaver Dam River, Rocky River, Cuyahoga County, OH
Bathymetric surveys at Highway Bridges Crossing the Missouri River in Kansas City, Missouri, using a multibeam echo sounder, 2010.

DOT National Transportation Integrated Search

2010-11-01

Bathymetric surveys were conducted by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, on the Missouri River in the vicinity of nine bridges at seven highway crossings in Kansas City, Missouri, in March 2010....
Curriculum Review Evaluation on Entrepreneurial Education in Cross River State Higher Institutions

ERIC Educational Resources Information Center

Ambekeh, Udida Lucy

2013-01-01

This study investigated curriculum organization and delivery towards functional entrepreneurial education transformation of students in Higher Institutions in Cross River State -- Nigeria. To guide the conduct of this study, two research questions and one hypothesis were formulated. Proportionate stratified sampling technique was used in the…
Load-based approaches for modelling visual clarity in streams at regional scale.

PubMed

Elliott, A H; Davies-Colley, R J; Parshotam, A; Ballantine, D

2013-01-01

Reduction of visual clarity in streams by diffuse sources of fine sediment is a cause of water quality impairment in New Zealand and internationally. In this paper we introduce the concept of a load of optical cross section (LOCS), which can be used for load-based management of light-attenuating substances and for water quality models that are based on mass accounting. In this approach, the beam attenuation coefficient (units of m(-1)) is estimated from the inverse of the visual clarity (units of m) measured with a black disc. This beam attenuation coefficient can also be considered as an optical cross section (OCS) per volume of water, analogous to a concentration. The instantaneous 'flux' of cross section is obtained from the attenuation coefficient multiplied by the water discharge, and this can be accumulated over time to give an accumulated 'load' of cross section (LOCS). Moreover, OCS is a conservative quantity, in the sense that the OCS of two combined water volumes is the sum of the OCS of the individual water volumes (barring effects such as coagulation, settling, or sorption). The LOCS can be calculated for a water quality station using rating curve methods applied to measured time series of visual clarity and flow. This approach was applied to the sites in New Zealand's National Rivers Water Quality Network (NRWQN). Although the attenuation coefficient follows roughly a power relation with flow at some sites, more flexible loess rating curves are required at other sites. The hybrid mechanistic-statistical catchment model SPARROW (SPAtially Referenced Regressions On Watershed attributes), which is based on a mass balance for mean annual load, was then applied to the NRWQN dataset. Preliminary results from this model are presented, highlighting the importance of factors related to erosion, such as rainfall, slope, hardness of catchment rock types, and the influence of pastoral development on the load of optical cross section.
Floodplain Sedimentation in Vegetated Areas of the Elwha River Floodplain, 2012-2014

NASA Astrophysics Data System (ADS)

Lauer, J. W.; Polka, J.

2014-12-01

The removal of the Elwha and Glines Canyon Dams from the Elwha River, near Port Angeles, Washington, has released a large pulse of sediment into the middle and lower reaches of the Elwha River. This sediment has important geomorphic, hydraulic, and ecological implications. Our project focuses on the deposition of fine sediment on vegetated parts of the Elwha floodplain using field observations of sediment accumulation in combination with a simplified physics numerical model, CAESAR-Lisflood. The floodplain of the Elwha is densely vegetated and in places is characterized by large amounts of local topographic variation. This makes measuring centimeter-scale overbank sedimentation difficult using traditional approaches such as lidar and total-station based cross-section surveys. To address this problem and to provide ground truth for more traditional surveying methods, we set up over 50 short (10-20 m long) cross-sections between sets of flagged trees and surveyed, at 1-meter intervals, ground elevation with respect to a spike set in each section. Nails in the trees ensure that the horizontal position of our measurements do not shift by more than a few centimeters from year to year. This approach allows sediment accumulation to be measured repeatedly with a precision we estimate to be on the order of a few centimeters, allowing us to estimate annual rates of local sedimentation. At a given point on the floodplain, sedimentation should depend significantly on the frequency of inundation. We simulate this for the 2012-2014 period using a CAESAR-Lisflood 2-D numerical model calibrated using a set of continuously recording staff gages. CAESAR-Lisflood uses simplified-physics hydraulic routines to efficiently simulate flow depth and velocity and to drive size-specific sediment transport and morphodynamic change. This allows the model to simulate changes in flood inundation probability for the post- removal period. CAESAR-based hydraulic results are used to interpret our field-based sedimentation measurements and to develop a reach-wide estimate of overall fine sediment accumulation on the floodplain. Our CAESAR runs, which are performed for the entire post-dam removal period, produce rich 2-D representations of velocity and bed texture that should be useful to other researchers studying this system.
Combining Imagery and Models to Understand River Dynamics

NASA Astrophysics Data System (ADS)

Blain, C. A.; Mied, R. P.; Linzell, R. S.

2014-12-01

Rivers pose one of the most challenging environments to characterize. Their geometric complexity and continually changing position and character are difficult to measure under optimal circumstances. Further compounding the problem is the often inaccessibility of these areas around the globe. Yet details of the river bank position and bed elevation are essential elements in the construction of accurate predictive river models. To meet this challenge, remote sensing imagery is first used to initialize the construction of advanced high resolution river circulation models. In turn, such models are applied to dynamically interpret remotely-sensed surface features. A method has been developed to automatically extract water and shoreline locations from arbitrarily sourced high resolution (~1m gsd) visual spectrum imagery without recourse to the spectral or color information. The approach relies on quantifying the difference in image texture between the relatively smooth water surface and the comparatively rough surface of surrounding land. Processing the segmented land/water interface results in ordered, continuous shoreline coordinates that bound river model construction. In the absence of observed bed elevations, one of several available analytic bathymetry cross-sectional relations are applied to complete the river model configuration. Successful application of this approach to the Snohomish River, WA and the Pearl River, MS are demonstrated. Once constructed, a hydrodynamic model of the river model can also be applied to unravel the dynamics responsible for observed surface features in the imagery. At a creek-river confluence in the Potomac River, MD, an ebb tide front observed in the imagery is analyzed using the model. The result is knowledge that an ebb shoal located just outside of the creek must be present and is essential for front formation. Furthermore, the front is found to be persistent throughout the tidal cycle, although it changes sign between ebb and flood phases. The presence of the creek only minimally modifies the underlying currents.
76 FR 63951 - Notice of Filing of Plats of Survey; Montana

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

... meanders of the former left bank of the Tongue River, downstream, through sections 27, 28, and 29, and the adjusted original meanders of the former right bank of the Tongue River, downstream, through sections 21... Tongue River, downstream, through sections 27 and 28, and a portion of section 29, the meanders of the...
Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Joint, Vertical Cross Bracing End Detail - Ceylon Covered Bridge, Limberlost Park, spanning Wabash River at County Road 900 South, Geneva, Adams County, IN

33 CFR 334.475 - Brickyard Creek and tributaries and the Broad River at Beaufort, SC.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and the Broad River at Beaufort, SC. 334.475 Section 334.475 Navigation and Navigable Waters CORPS OF....475 Brickyard Creek and tributaries and the Broad River at Beaufort, SC. (a) The areas: (1) That...°. (9) (Laurel Bay Military Family Housing Area, Broad River). That section of the Broad River...
33 CFR 334.475 - Brickyard Creek and tributaries and the Broad River at Beaufort, SC.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and the Broad River at Beaufort, SC. 334.475 Section 334.475 Navigation and Navigable Waters CORPS OF....475 Brickyard Creek and tributaries and the Broad River at Beaufort, SC. (a) The areas: (1) That...°. (9) (Laurel Bay Military Family Housing Area, Broad River). That section of the Broad River...
33 CFR 334.475 - Brickyard Creek and tributaries and the Broad River at Beaufort, SC.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and the Broad River at Beaufort, SC. 334.475 Section 334.475 Navigation and Navigable Waters CORPS OF....475 Brickyard Creek and tributaries and the Broad River at Beaufort, SC. (a) The areas: (1) That...°. (9) (Laurel Bay Military Family Housing Area, Broad River). That section of the Broad River...
33 CFR 334.475 - Brickyard Creek and tributaries and the Broad River at Beaufort, SC.

Code of Federal Regulations, 2011 CFR

2011-07-01

... and the Broad River at Beaufort, SC. 334.475 Section 334.475 Navigation and Navigable Waters CORPS OF....475 Brickyard Creek and tributaries and the Broad River at Beaufort, SC. (a) The areas: (1) That...°. (9) (Laurel Bay Military Family Housing Area, Broad River). That section of the Broad River...
33 CFR 334.475 - Brickyard Creek and tributaries and the Broad River at Beaufort, SC.

Code of Federal Regulations, 2010 CFR

2010-07-01

... and the Broad River at Beaufort, SC. 334.475 Section 334.475 Navigation and Navigable Waters CORPS OF....475 Brickyard Creek and tributaries and the Broad River at Beaufort, SC. (a) The areas: (1) That...°. (9) (Laurel Bay Military Family Housing Area, Broad River). That section of the Broad River...
Adaptation to floods in future climate: a practical approach

NASA Astrophysics Data System (ADS)

Doroszkiewicz, Joanna; Romanowicz, Renata; Radon, Radoslaw; Hisdal, Hege

2016-04-01

In this study some aspects of the application of the 1D hydraulic model are discussed with a focus on its suitability for flood adaptation under future climate conditions. The Biała Tarnowska catchment is used as a case study. A 1D hydraulic model is developed for the evaluation of inundation extent and risk maps in future climatic conditions. We analyse the following flood indices: (i) extent of inundation area; (ii) depth of water on flooded land; (iii) the flood wave duration; (iv) the volume of a flood wave over the threshold value. In this study we derive a model cross-section geometry following the results of primary research based on a 500-year flood inundation extent. We compare two methods of localisation of cross-sections from the point of view of their suitability to the derivation of the most precise inundation outlines. The aim is to specify embankment heights along the river channel that would protect the river valley in the most vulnerable locations under future climatic conditions. We present an experimental design for scenario analysis studies and uncertainty reduction options for future climate projections obtained from the EUROCORDEX project. Acknowledgements: This work was supported by the project CHIHE (Climate Change Impact on Hydrological Extremes), carried out in the Institute of Geophysics Polish Academy of Sciences, funded by Norway Grants (contract No. Pol-Nor/196243/80/2013). The hydro-meteorological observations were provided by the Institute of Meteorology and Water Management (IMGW), Poland.
Fish assemblage structure and habitat associations in a large western river system

USGS Publications Warehouse

Smith, C.D.; Quist, Michael C.; Hardy, R. S.

2016-01-01

Longitudinal gradients of fish assemblage and habitat structure were investigated in the Kootenai River of northern Idaho. A total of 43 500-m river reaches was sampled repeatedly with several techniques (boat-mounted electrofishing, hoop nets and benthic trawls) in the summers of 2012 and 2013. Differences in habitat and fish assemblage structure were apparent along the longitudinal gradient of the Kootenai River. Habitat characteristics (e.g. depth, substrate composition and water velocity) were related to fish assemblage structure in three different geomorphic river sections. Upper river sections were characterized by native salmonids (e.g. mountain whitefish Prosopium williamsoni), whereas native cyprinids (peamouth Mylocheilus caurinus, northern pikeminnow Ptychocheilus oregonensis) and non-native fishes (pumpkinseed Lepomis gibbosus, yellow perch Perca flavescens) were common in the downstream section. Overall, a general pattern of species addition from upstream to downstream sections was discovered and is likely related to increased habitat complexity and additions of non-native species in downstream sections. Assemblage structure of the upper sections were similar, but were both dissimilar to the lower section of the Kootenai River. Species-specific hurdle regressions indicated the relationships among habitat characteristics and the predicted probability of occurrence and relative abundance varied by species. Understanding fish assemblage structure in relation to habitat could improve conservation efforts of rare fishes and improve management of coldwater river systems.
A Cultural Resources Inventory of the Pearl River Basin, Louisiana and Mississippi. Volume II.

DTIC Science & Technology

1982-04-01

its environs. 11 Finlay , A. ca. Map of the State of Louisiana. (L.S.U.) 1820 The boundaries of St. Tammany and Washington Parishes are defined. Carez...crossing the Pearl River. Author Unknown 1822 Mississippi. (M.S.U.) Several trails are shown crossing the Pearl River. Ford, N . Columbia, Monticello, and...Jackson, Mississippi are depicted. The Choctaw agency is shown at the northern part of the Pearl. County boundaries are defined. j Finlay , A. 1824
Attitudes toward nonsmoking policies and tobacco tax increases: a cross-sectional study among Vietnamese adults.

PubMed

Dao, Thi Minh An; Hoang, Van Minh; Le, Thi Huong; Kim, Bao Giang; Le, Thi Thanh Xuan; Pham, Thi Quynh Nga; Hsia, Jason

2015-03-01

Following the 2009 update of the 2005 Framework Convention on Tobacco Control, Vietnam issued a new policy to ban smoking at workplaces and public places. This cross-sectional survey explored public attitudes toward this new regulation and provides evidence to inform future laws. Using stratified cluster sampling, 10 383 Vietnamese people older than 15 years were drawn from 11 142 selected households. Policies mandating "no smoking at workplaces" were supported by 88.7% of Vietnamese adults, whereas "no smoking in public places" and "increasing the tobacco tax" received less support. Educational level, knowledge of health effects, access to information on quitting and smoking health risks, smoking status, ethnicity, and region had significant associations with positive attitudes toward all 3 tobacco control policies. Adults belonging to the non-Kinh ethnic group, those who do not live in the Red river delta, people with lower educational levels, and current smokers should be targeted in tobacco control communication programs. © 2012 APJPH.
Hydro- and sediment dynamics in the estuary zone of the Mekong Delta: case study Dinh An estuary.

NASA Astrophysics Data System (ADS)

Tran, Anh Tuan; Thoss, Heiko; Gratiot, Nicolas; Dussouillez, Philippe; Brunier, Guillaume; Apel, Heiko

2017-04-01

The Mekong River is the tenth largest river in the world, covers an area of 795,000 km2, 4400km in length, the main river flows over the six countries including: China, Myanmar, Thailand, Laos, Cambodia and Vietnam. Its water discharge is 470 km3year-1 and the sediment discharge is estimated about 160 million ton year-1. The sediment transported by the Mekong River is the key factor in the formation and development of the delta. It is a vital factor for the stability of the coastline and river banks. Furthermore it compensates land subsidence by floodplain deposition, and is the major natural nutrient source for agriculture and aquaculture. However, only a few studies were conducted to characterize and quantify sediment properties and process in the Delta. Also the morphodynamic processes were hardly studied systematically. Hence, this study targets to fill some important and open knowledge gaps with extensive field works that provide important information about the sediment properties and hydrodynamic processes in different seasons Firstly three field survey campaigns are carried out along a 30 km section of the Bassac River from the beginning of Cu Lao Dung Island to Dinh An estuary in 2015 and 2016. During the field campaign, the movement of the salt wedge and the turbidity were monitored by vertical profiles along the river, as well as discharge measurements by ADCP were carried out at three cross sections continuously for 72 hours. The extension of the salt wedge in the river was determined, along with mixing processes. The movement and dynamics observed under different flow conditions indicate that sediment was pumped during low flow upwards the river, while during high flow net transport towards the sea dominated. Also a distinct difference in the sediment properties in the different seasons was observed, with a general tendency towards a higher proportion of coarser particles in the high flow season. These quantitative results give insights into the important sediment dynamics in the estuary and the vital sediment transport towards the coast of the Mekong delta, which is the basis for morphological stability of the coast. The results of the field campaigns will be used for the development of a detailed 3D sediment transport model (Delft 3D) for the quantification of the morphodynamic processes at Dinh An estuary.
77 FR 57024 - Drawbridge Operation Regulation; Tombigbee River, AL

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-17

... lift span bridge across the Tombigbee River at Naheola, Marengo and Choctaw Counties, Alabama. The... MNBR vertical lift span bridge crosses the Tombigbee River at mile 128.6 (Black Warrior Tombigbee... Meridian and Bigbee Railroad (MNBR) vertical lift span bridge across the Tombigbee River, mile 128.6 (Black...
77 FR 25655 - Drawbridge Operation Regulation; Tombigbee River, AL

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-01

... Meridian and Bigbee Railroad (MNBR) vertical lift span bridge across the Tombigbee River at Naheola... The MNBR vertical lift span bridge crosses the Tombigbee River at mile 128.6 (Black Warrior Tombigbee... Railroad (MNBR) vertical lift span bridge across the Tombigbee River, mile 128.6 (Black Warrior Tombigbee...
Integrating channel form and processes in the Gangetic plains rivers: Implications for geomorphic diversity

NASA Astrophysics Data System (ADS)

Roy, N. G.; Sinha, R.

2018-02-01

Geomorphic diversity at a variety of spatial and temporal scales has been studied in the western Ganga plains (WGP), India, to isolate the dominating factors at each scale that have the potential to cause major geomorphic change. The Ganga River and its major tributaries draining the WGP have been investigated in terms of longitudinal, cross-sectional, and planform morphology to assess the influence of potential controls such as climate, geology, topography, land use, hydrology, and sediment transport. These data were then compared with those from the rivers draining the eastern Ganga plains (EGP) to understand the geomorphic diversity across the Ganga plains and the causal factors. Our investigations suggest that in-channel geomorphic diversity over decadal scale in rivers with low width-to-depth (W/D) ratio is caused by periodic incision/aggradation, but it is driven by channel avulsion in rivers characterized by high W/D ratio. Similarly, planform (reach-scale) parameters such as sinuosity and braid-channel-ratio are influenced by intrinsic factors such as changes in hydrological conditions and morphodynamics (cutoffs, small-scale avulsion) that are in turn impacted by natural and human-induced factors. Finally, we have isolated the climatic and hydrologic effects on the longitudinal profile concavity of alluvial trunk channels in tectonically stable and unstable landscapes. We demonstrate that the rivers flowing through a tectonically stable landscape are graded in nature where higher discharge tends to create more concave longitudinal profiles compared to those in tectonically unstable landscape at 103-year scale.
River banks and channel axis curvature: Effects on the longitudinal dispersion in alluvial rivers

NASA Astrophysics Data System (ADS)

Lanzoni, Stefano; Ferdousi, Amena; Tambroni, Nicoletta

2018-03-01

The fate and transport of soluble contaminants released in natural streams are strongly dependent on the spatial variations of the flow field and of the bed topography. These variations are essentially related to the presence of the channel banks and to the planform configuration of the channel. Large velocity gradients arise near to the channel banks, where the flow depth decreases to zero. Moreover, single thread alluvial rivers are seldom straight, and usually exhibit meandering planforms and a bed topography that deviates from the plane configuration. Channel axis curvature and movable bed deformations drive secondary helical currents which enhance both cross sectional velocity gradients and transverse mixing, thus crucially influencing longitudinal dispersion. The present contribution sets up a rational framework which, assuming mild sloping banks and taking advantage of the weakly meandering character often exhibited by natural streams, leads to an analytical estimate of the contribution to longitudinal dispersion associated with spatial non-uniformities of the flow field. The resulting relationship stems from a physics-based modeling of the flow in natural rivers, and expresses the bend averaged longitudinal dispersion coefficient as a function of the relevant hydraulic and morphologic parameters. The treatment of the problem is river specific, since it relies on an explicit spatial description, although linearized, of the flow field that establishes in the investigated river. Comparison with field data available from tracer tests supports the robustness of the proposed framework, given also the complexity of the processes that affect dispersion dynamics in real streams.
Developing and testing a framework for alternative ownership, tenure and governance strategies for the proposed Detroit-Windsor River crossing : phase I report, February 2009.

DOT National Transportation Integrated Search

2009-02-01

This study focuses on a proposed international crossing across the Detroit River, connecting the cities of Detroit, Michigan and Windsor, Canada, and replacing the current Ambassador Bridge and Detroit-Windsor Tunnel, both built during the late 1920s...
75 FR 78228 - Takes of Marine Mammals Incidental to Specified Activities; Columbia River Crossing Project...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-15

... (Zalophus californianus), and harbor seals (Phoca vitulina). Specified Activities CRC is proposing a...-water bents, consisting of one to three drilled shafts. The permanent in-water piers of both the Columbia River and North Portland Harbor crossings will be constructed using drilled shafts, rather than...
Analysis of stated preference survey data for river-crossing travel behavior in the Portland/Vancouver metropolitan area

DOT National Transportation Integrated Search

1997-01-01

The MPO in the Southwest Washington and Oregon initiated a major activity and travel behavior survey from the Spring of 1994 to the Fall 1994, including the Stated Preference survey for river-crossing trip behavior. The purpose of the survey is to ga...
Battle Analysis: Rapido River Crossing, Offensive, Deliberate Attack, River Crossing, January 1944

DTIC Science & Technology

1984-05-01

Even the few employed were difficult to use due to the slippery surface and the lack of handrails. Direct and indirect fire chewed them up. The...were placed in the water and went down quickly, sometimes carrying men loaded with heavy combat equipment. 42 mmmimm^^mtm—mm^ elm ^tmmMMM
Entrepreneurial Training Needs of Illiterate Women in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ingwu, Emmanuel U.; Okey, Stella-Maris A.

2013-01-01

In order to improve on the curriculum and participation rate of adult learners in the current Adult Basic Education (ABE) program in Nigeria, this explorative study investigated the entrepreneurial (or vocational) training needs of illiterate women in Cross River State (CRS). Three research questions were posed to elicit from the participants…
On the role of flood wave celerity-discharge relationship and its applications on hydrological studies

NASA Astrophysics Data System (ADS)

Fleischmann, Ayan; Collischonn, Walter; Jardim, Pedro; Meyer, Aline; Paiva, Rodrigo

2017-04-01

The non-linear relationship between flood wave celerity (C) and discharge (Q) plays an important role on defining how flood waves are routed through the river network. The behavior of this curve is driven by cross section geometry, which leads to increasing celerity with discharge in rivers without floodplains. In reaches with floodplain storage, C may decrease after bankfull Q. Thus, in a set of studies we investigate the effects of C x Q relationships on the basin hydrological response. (i) We studied these curves for several Brazilian river reaches, and analyzed to which extent they are related to river channel geometry and other characteristics (e.g., slope, width, drainage area and sinuosity). (ii) It is shown through empirical, analytical and numerical experiments how C x Q relation affects hydrograph skewness, and how the decreasing relationship existent in rivers with important floodplain storage leads to negatively skewed hydrographs, such as in the Amazon and Pantanal regions, which could be used to infer important floodplain processes (e.g., presence of overbank flow wetlands, which feature negatively skewed hydrographs or interfluvial wetlands not directly connected to rivers). (iii) Finally, we found that it is possible to use these concepts to calibrate the effective bathymetry of a hydrodynamic model by fitting the C x Q relationship using SCE-UA optimization method. Our results show how important it is to investigate the non-linear hydraulic processes occurring throughout river basins to understand the overall hydrological response, and propose new frameworks to assist such studies, including the evaluation of hydrograph skewness and estimation of hydraulic geometry.

River-Based Experiential Learning: the Bear River Fellows Program

NASA Astrophysics Data System (ADS)

Rosenberg, D. E.; Shirley, B.; Roark, M. F.

2012-12-01

The Department of Civil and Environmental Engineering, Outdoor Recreation, and Parks and Recreation programs at Utah State University (USU) have partnered to offer a new, unique river-based experiential learning opportunity for undergraduates called the Bear River Fellows Program. The program allows incoming freshmen Fellows to experience a river first hand during a 5-day/4-night river trip on the nearby Bear River two weeks before the start of their first Fall semester. As part of the program, Fellows will navigate the Bear River in canoes, camp along the banks, interact with local water and environmental managers, collect channel cross section, stream flow, vegetation cover, and topological complexity data, meet other incoming freshmen, interact with faculty and graduate students, develop boating and leadership skills, problem solve, and participate as full members of the trip team. Subsequently, Fellows will get paid as undergraduate researchers during their Fall and Spring Freshman semesters to analyze, synthesize, and present the field data they collect. The program is a collaborative effort between two USU academic units and the (non-academic) division of Student Services and supports a larger National Science Foundation funded environmental modelling and management project for the lower Bear River, Utah watershed. We have advertised the program via Facebook and emails to incoming USU freshmen, received 35 applications (60% women), and accepted 5 Fellows into the program (3 female and 2 male). The river trip departs August 14, 2012. The poster will overview the Bear River Fellows Program and present qualitative and preliminary outcomes emerging from the trip and Fellows' work through the Fall semester with the field data they collect. We will also undertake more rigorous and longer longitudinal quantitative evaluation of Program outcomes (for example, in problem-solving and leadership) both in Spring 2013 and in subsequent 2013 and 2014 offerings of the program.
The Hidden Tragedy of Rivers: A Decade of Unintentional Fatal Drowning in Australia

PubMed Central

Leggat, Peter A.

2016-01-01

Objective(s) Describe unintentional drowning deaths in rivers, creeks and streams (rivers) in Australia and identify risk factors to inform prevention. Design & Setting This study is a cross-sectional, total population audit of all unintentional fatal drownings in Australian rivers between 1-July-2002 and 30-June-2012 using Australian coronial data. A modified Bonferroni test has been applied, deeming statistical significance p<0.03 and p<0.04 respectively. Results Rivers (n = 770; 26.6%) were the leading location among the 2,892 people who died from unintentional fatal drowning. This is a rate of 0.37/100,000 people / annum. Within river drowning deaths common groups include; males (80.4%), adults (85.3%), adults who have consumed alcohol (25.5%), people who fell in (21.3%), people involved in non-aquatic transport incidents (18.2%) and locals (74.0%). Children were 1.75 times more likely than adults (p<0.04) to drown in rivers as a result of a fall and adults 1.50 times more likely to drown in rivers as a result of watercraft incidents when compared to children. When compared to males, females were 2.27 and 4.45 times respectively more likely to drown in rivers as a result of incidents involving non-aquatic transport (p<0.04) and being swept away by floodwaters (p<0.04). Males were 2.66 and 4.27 times respectively more likely to drown in rivers as a result of watercraft incidents (p<0.04) and as a result of jumping in (p<0.04) when compared to females. Conclusion(s) While rivers are the leading location for drowning in Australia, little is understood about the risks. This study has identified key groups (males, adults, locals) and activities. While males were more likely to drown, the risk profile for females differed. PMID:27517313
Integrating Satellite Image Identification and River Routing Simulation into the Groundwater Simulation of Chou-Shui Basin

NASA Astrophysics Data System (ADS)

Yao, Y.; Yang, S.; Chen, Y.; Chang, L.; Chiang, C.; Huang, C.; Chen, J.

2012-12-01

Many groundwater simulation models have been developed for Chou-Shui River alluvial fan which is one of the most important groundwater areas in Taiwan. However, the exchange quantity between Chou-Shui River, the major river in this area, and the groundwater system itself is seldom studied. In this study, the exchange is evaluated using a river package (RIV) in the groundwater simulation model, MODFLOW 2000. Several critical parameters and variables used in RIV such as wet area and river level for each cell below the Chou-Shui River are respectively determined by satellite image identification and HEC-RAS simulation. The monthly average of river levels obtained from four stations include Chang-Yun Bridge, Xi-Bin Bridge, Chi-Chiang Bridge and Si-Jou Bridge during 2008 and the river cross-section measured on December 2007 are used in the construction of HEC-RAS model. Four FORMOSAT multispectral satellite images respectively obtained on January 2008, April 2008, July 2008, and November 2008 are used to identify the wet area of Chou-Shui River during different seasons. Integrating the simulation level provided by HEC-RAS and the identification result are used as the assignment of RIV. First, based on the simulation results of HEC-RAS, the water level differences between flooding period and draught period are 1.4 (m) and 2.0 (m) for Xi-Bin Bridge station (downstream) and Chang-Yun Bridge station (upstream) respectively. Second, based on the identified results, the wet areas for four seasons are 24, 24, 40 and 12 (km2) respectively. The variation range of areas in 2008 is huge that the area for winter is just 30% of the area for summer. Third, based on the simulation of MODFLOW 2000 and RIV, the exchange between the river and the groundwater system is 414 million cubic meters which contains 526 for recharge to river and 112 for discharging from river during 2008. The total recharge includes river exchange and recharge from non-river area is 2023 million cubic meters. The pumping quantity is 1930 million cubic meters.
16. INTAKE PIER, PLANS ELEVATIONS, AND SECTIONS, SHEETS 5 OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. INTAKE PIER, PLANS ELEVATIONS, AND SECTIONS, SHEETS 5 OF 117, 1920. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA
19. INTAKE CONDUITS, PROFILE, SECTIONS, AND DETAILS, SHEET 10 OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. INTAKE CONDUITS, PROFILE, SECTIONS, AND DETAILS, SHEET 10 OF 117, 1920. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA
A PREDICTIVE MODEL FOR ANTI-DEGRADATION MONITORING OF THE DELAWARE RIVER

EPA Science Inventory

The non-tidal portion of the Delaware River consists of many large sections designated as Wild and Scenic Rivers and passes through two national parks. Although there is increasing pressure on the watershed, large sections of the mainstem of the river can be considered to be in m...
Potential interaction between transport and stream networks over the lowland rivers in Eastern India.

PubMed

Roy, Suvendu; Sahu, Abhay Sankar

2017-07-15

Extension of transport networks supports good accessibility and associated with the development of a region. However, transport lines have fragmented the regional landscape and disturbed the natural interplay between rivers and their floodplains. Spatial analysis using multiple buffers provides information about the potential interaction between road and stream networks and their impact on channel morphology of a small watershed in the Lower Gangetic Plain. Present study is tried to understand the lateral and longitudinal disconnection in headwater stream by rural roads with the integration of geoinformatics and field survey. Significant (p < 0.001) growth of total road length and number of road-stream crossing in the last five decades (1970s-2010s) contribute to making longitudinal and lateral disconnection in the fluvial system of Kunur River Basin. Channel geometry from ten road-stream crossings shows significant (p = 0.01) differences between upstream and downstream of crossing structure and created problems like downstream scouring, increased drop height at outlet, formation of stable bars, severe bank erosion, and make barriers for river biota. The hydro-geomorphic processes are also adversely affected due to lateral disconnection and input of fine to coarse sediments from the river side growth of unpaved road (1922%). Limited streamside development, delineation of stream corridor, regular monitoring and engineering efficiency for the construction of road and road-stream crossing might be effective in managing river geomorphology and riverine landscape. Copyright © 2017 Elsevier Ltd. All rights reserved.
Discharge estimation for the Upper Brahmaputra River in the Tibetan Plateau using multi-source remote sensing data

NASA Astrophysics Data System (ADS)

Huang, Q.; Long, D.; Du, M.; Hong, Y.

2017-12-01

River discharge is among the most important hydrological variables of hydrologists' concern, as it links drinking water supply, irrigation, and flood forecast together. Despite its importance, there are extremely limited gauging stations across most of alpine regions such as the Tibetan Plateau (TP) known as Asia's water towers. Use of remote sensing combined with partial in situ discharge measurements is a promising way of retrieving river discharge over ungauged or poorly gauged basins. Successful discharge estimation depends largely on accurate water width (area) and water level, but it is challenging to obtain these variables for alpine regions from a single satellite platform due to narrow river channels, complex terrain, and limited observations. Here, we used high-spatial-resolution images from Landsat series to derive water area, and satellite altimetry (Jason 2) to derive water level for the Upper Brahmaputra River (UBR) in the TP with narrow river width (less than 400 m in most occasions). We performed waveform retracking using a 50% Threshold and Ice-1 Combined algorithm (TIC) developed in this study to obtain accurate water level measurements. The discharge was estimated well using a range of derived formulas including the power function between water level and discharge, and that between water area and discharge suitable for the triangular cross-section around the Nuxia gauging station in the UBR. Results showed that the power function using Jason 2-derived water levels after performing waveform retracking performed best, showing an overall NSE value of 0.92. The proposed approach for remotely sensed river discharge is effective in the UBR and possibly other alpine rivers globally.
Collection methods, data compilation, and lessons learned from a study of stream geomorphology associated with riparian cattle grazing along the Fever River, University of Wisconsin- Platteville Pioneer Farm, Wisconsin, 2004–11

USGS Publications Warehouse

Peppler, Marie C.; Fitzpatrick, Faith A.

2018-03-09

Stream geomorphic characteristics were monitored along a 0.8-mile reach of the Fever River in the Driftless Area of southwestern Wisconsin from 2004 to 2011 where cattle grazed in paddocks along the riverbank at the University of Wisconsin-Platteville’s Pioneer Farm. The study reach encompassed seven paddocks that covered a total of 30 acres on both sides of the river. Monitoring data included channel crosssection surveys, eroding bank measurements and photograph points, erosion-pin measurements, longitudinal profile surveys, measurements of the volume of soft sediment in the channel, and repeated time-lapse photographs. Characteristics were summarized into subreaches by use of a geographic information system. From 2004 to 2007, baseline monitoring was done to identify geomorphic conditions prior to evaluating the effects of management alternatives for riparian grazing. Subsequent to the full-scale baseline monitoring, additional data were collected from 2007 to 2011. Samples of eroding bank and in-channel soft sediment were collected and analyzed for dry bulk density in 2008 for use in a sediment budget. One of the pastures was excluded from cattle grazing in the fall of 2007; in 2009 channel cross sections, longitudinal profiles, erosion-pin measurements, photographs, and a soft sediment survey were again collected along the full 0.8-mile reach for a comparison to baseline monitoring data. Channel cross sections were surveyed a final time in 2011. Lessons learned from bank monitoring with erosion pins were most numerous and included the need for consistent tracking of each pin and whether there was deposition or erosion, timing of measurements and bank conditions during measurements (frozen, postflood), and awareness of pins loosening in place. Repeated freezing and thawing of banks and consequential mass wasting and jointing enhance fluvial erosion. Monitoring equipment in the paddocks was kept flush to the ground or located high on posts to avoid injuring the cattle.
Evaluation of Fluoride Retention Due to Most Commonly Consumed Estuarine Fishes Among Fish Consuming Population of Andhra Pradesh as a Contributing Factor to Dental Fluorosis: A Cross-Sectional Study

PubMed Central

Ganta, Shravani; Nagaraj, Anup; Pareek, Sonia; Sidiq, Mohsin; Singh, Kushpal; Vishnani, Preeti

2015-01-01

Background Fluoride in drinking water is known for both beneficial and detrimental effects on health. The principal sources of fluoride include water, some species of vegetation, certain edible marine animals, dust and industrial processes. The purpose of this study was to evaluate the fluoride retention of most commonly consumed estuarine fishes among fish consuming population of Andhra Pradesh. Materials and Methods A cross-sectional study was conducted to evaluate the amount of fluoride retention due to ten most commonly consumed estuarine fishes as a contributing factor to Fluorosis by SPADNS Spectrophotometric method. The presence and severity of dental fluorosis among fish consuming population was recorded using Community Fluorosis Index. Statistical analysis was done using MedCalc v12.2.1.0 software. Results For Sea water fishes, the fluoride levels in bone were maximum in Indian Sardine (4.22 ppm). Amongst the river water fishes, the fluoride levels in bone were maximum in Catla (1.51 ppm). Also, the mean total fluoride concentrations of all the river fishes in skin, muscle and bone were less (0.86 ppm) as compared to the sea water fishes (2.59 ppm). It was unveiled that sea fishes accumulate relatively large amounts of Fluoride as compared to the river water fishes. The mean Community Fluorosis Index was found to be 1.06 amongst a sampled fish consuming population. Evaluation by Community Index for Dental fluorosis (CFI) suggested that fluorosis is of medium public health importance. Conclusion It was analysed that bone tends to accumulate more amount of fluoride followed by muscle and skin which might be due to the increased permeability and chemical trapping of fluoride inside the tissues. The amount of fluoride present in the fishes is directly related to the severity of fluorosis amongst fish consuming population, suggesting fishes as a contributing factor to fluorosis depending upon the dietary consumption. PMID:26266208
Evaluation of Fluoride Retention Due to Most Commonly Consumed Estuarine Fishes Among Fish Consuming Population of Andhra Pradesh as a Contributing Factor to Dental Fluorosis: A Cross-Sectional Study.

PubMed

Ganta, Shravani; Yousuf, Asif; Nagaraj, Anup; Pareek, Sonia; Sidiq, Mohsin; Singh, Kushpal; Vishnani, Preeti

2015-06-01

Fluoride in drinking water is known for both beneficial and detrimental effects on health. The principal sources of fluoride include water, some species of vegetation, certain edible marine animals, dust and industrial processes. The purpose of this study was to evaluate the fluoride retention of most commonly consumed estuarine fishes among fish consuming population of Andhra Pradesh. A cross-sectional study was conducted to evaluate the amount of fluoride retention due to ten most commonly consumed estuarine fishes as a contributing factor to Fluorosis by SPADNS Spectrophotometric method. The presence and severity of dental fluorosis among fish consuming population was recorded using Community Fluorosis Index. Statistical analysis was done using MedCalc v12.2.1.0 software. For Sea water fishes, the fluoride levels in bone were maximum in Indian Sardine (4.22 ppm). Amongst the river water fishes, the fluoride levels in bone were maximum in Catla (1.51 ppm). Also, the mean total fluoride concentrations of all the river fishes in skin, muscle and bone were less (0.86 ppm) as compared to the sea water fishes (2.59 ppm). It was unveiled that sea fishes accumulate relatively large amounts of Fluoride as compared to the river water fishes. The mean Community Fluorosis Index was found to be 1.06 amongst a sampled fish consuming population. Evaluation by Community Index for Dental fluorosis (CFI) suggested that fluorosis is of medium public health importance. It was analysed that bone tends to accumulate more amount of fluoride followed by muscle and skin which might be due to the increased permeability and chemical trapping of fluoride inside the tissues. The amount of fluoride present in the fishes is directly related to the severity of fluorosis amongst fish consuming population, suggesting fishes as a contributing factor to fluorosis depending upon the dietary consumption.
Repeated surveys by acoustic Doppler current profiler for flow and sediment dynamics in a tidal river

USGS Publications Warehouse

Dinehart, R.L.; Burau, J.R.

2005-01-01

A strategy of repeated surveys by acoustic Doppler current profiler (ADCP) was applied in a tidal river to map velocity vectors and suspended-sediment indicators. The Sacramento River at the junction with the Delta Cross Channel at Walnut Grove, California, was surveyed over several tidal cycles in the Fall of 2000 and 2001 with a vessel-mounted ADCP. Velocity profiles were recorded along flow-defining survey paths, with surveys repeated every 27 min through a diurnal tidal cycle. Velocity vectors along each survey path were interpolated to a three-dimensional Cartesian grid that conformed to local bathymetry. A separate array of vectors was interpolated onto a grid from each survey. By displaying interpolated vector grids sequentially with computer animation, flow dynamics of the reach could be studied in three-dimensions as flow responded to the tidal cycle. Velocity streamtraces in the grid showed the upwelling of flow from the bottom of the Sacramento River channel into the Delta Cross Channel. The sequential display of vector grids showed that water in the canal briefly returned into the Sacramento River after peak flood tides, which had not been known previously. In addition to velocity vectors, ADCP data were processed to derive channel bathymetry and a spatial indicator for suspended-sediment concentration. Individual beam distances to bed, recorded by the ADCP, were transformed to yield bathymetry accurate enough to resolve small bedforms within the study reach. While recording velocity, ADCPs also record the intensity of acoustic backscatter from particles suspended in the flow. Sequential surveys of backscatter intensity were interpolated to grids and animated to indicate the spatial movement of suspended sediment through the study reach. Calculation of backscatter flux through cross-sectional grids provided a first step for computation of suspended-sediment discharge, the second step being a calibrated relation between backscatter intensity and sediment concentration. Spatial analyses of ADCP data showed that a strategy of repeated surveys and flow-field interpolation has the potential to simplify computation of flow and sediment discharge through complex waterways. The use of trade, product, industry, or firm names in this report is for descriptive purposes only and does not constitute endorsement of products by the US Government. ?? 2005 Elsevier B.V. All rights reserved.
Biological Agents Influencing Physical Process in a Stream: A Case Study in Response to Human-Induced Alteration

NASA Astrophysics Data System (ADS)

Sondossi, H. A.; Bienz, C.

2013-12-01

We present a case study of the Upper Williamson River, a major tributary to Upper Klamath Lake (UKL), to demonstrate illustrate the importance of biophysical interactions. The Klamath River is called 'the upside-down river' by some, due to its peculiar longitudinal profile--low-gradient at the headwaters east of the Cascade Range and steeper close to the mouth as it crosses the Cascades. The Upper Williamson River, as with other tributaries of UKL, flows through highly erodible volcanic ash (pumice) deposits of the Mazama eruption ~7,000 years ago, which created Crater Lake. There is little or no gravel in the broad, shallow alluvial valley of the River. We make the case that in this particular setting, the role of biological agents (e.g., riparian vegetation) is even more prominent than in settings with normal silica-derived sediment. Therefore, typical agricultural practices (removal of woody riparian vegetation, livestock grazing and trampling, etc.) cause rapid and severe channel response and therefore habitat degradation. However, when appropriately restored the recovery is also rapid and drastic. This spring-fed stream with few tributaries in the study area conveys relatively stable discharge, and has good water quality particularly in the upper reaches. It historically supported a population of native redband trout (Oncorhynchus mykiss gairdnerii), and the candidate species (for listing under the Endangered Species Act) Oregon spotted frog (Rana pretiosa) and countless other avian species. In the late 20th Century, after decades of heavy grazing and active removal of willows from the floodplain, the River banks were nearly bare and unstable. The channel was wide, shallow, and smooth. Consequently, poor water quality, particularly high temperature rendered the stream extremely poor habitat. With controlled grazing, re-establishment of willow galleries, and addition of large woody debris (LWD) the channel has recovered to a narrower, deeper cross-section, with ample depth variability. Water quality has improved to the point that it supports a healthy and expanding population of redband trout alongside introduced eastern brook trout (Salvelinus fontinalis). There have been no sightings of Oregon spotted frog yet, but the habitat is deemed suitable.
Fecal-indicator bacteria in the Allegheny, Monongahela, and Ohio Rivers and selected tributaries, Allegheny County, Pennsylvania, 2001-2005

USGS Publications Warehouse

Buckwalter, Theodore F.; Zimmerman, Tammy M.; Fulton, John W.

2006-01-01

Concentrations of fecal-indicator bacteria were determined in 1,027 water-quality samples collected from July 2001 through August 2005 during dry- (72-hour dry antecedent period) and wet-weather (48-hour dry antecedent period and at least 0.3 inch of rain in a 24-hour period) conditions in the Allegheny, Monongahela, and Ohio Rivers (locally referred to as the Three Rivers) and selected tributaries in Allegheny County. Samples were collected at five sampling sites on the Three Rivers and at eight sites on four tributaries to the Three Rivers having combined sewer overflows. Water samples were analyzed for three fecal-indicator organisms fecal coliform, Escherichia coli (E. coli), and enterococci bacteria. Left-bank and right-bank surface-water samples were collected in addition to a cross-section composite sample at each site. Concentrations of fecal coliform, E. coli, and enterococci were detected in 98.6, 98.5, and 87.7 percent of all samples, respectively. The maximum fecal-indicator bacteria concentrations were collected from Sawmill Run, a tributary to the Ohio River; Sawmill Run at Duquesne Heights had concentrations of fecal coliform, E. coli, and enterococci of 410,000, 510,000, and 180,000 col/100 mL, respectively, following a large storm. The samples collected in the Three Rivers and selected tributaries frequently exceeded established recreational standards and criteria for bacteria. Concentrations of fecal coliform exceeded the Pennsylvania water-quality standard (200 col/100 mL) in approximately 63 percent of the samples. Sample concentrations of E. coli and enterococci exceeded the U.S. Environmental Protection Agency (USEPA) water-quality criteria (235 and 61 col/100 mL, respectively) in about 53 and 47 percent, respectively, of the samples. Fecal-indicator bacteria were most strongly correlated with streamflow, specific conductance, and turbidity. These correlations most frequently were observed in samples collected from tributary sites. Fecal-indicator bacteria concentrations and turbidity were correlated to the location of sample collection in the cross section. Most differences were between bank and composite samples; differences between right-bank and left-bank samples were rarely observed. The Allegheny River sites had more significant correlations than the Monongahela or Ohio River sites. Comparisons were made between fecal-indicator bacteria in composite samples collected during dry-weather, wet-weather day-one, wet-weather day-two (tributary sites only), and wet-weather day-three (Three Rivers sites only) events in the Three Rivers and selected tributary sites. The lowest median bacteria concentrations generally were observed in the dry-weather composite samples. All median bacteria concentrations in dry-weather composite samples in the five Three Rivers sites were below water-quality standards and criteria; bacteria concentrations in the upstream tributary sites rarely met all standards or criteria. Only Turtle Creek, Thompson Run, and Chartiers Creek had at least one median bacteria concentration below water-quality standards or criteria. Median bacteria concentrations in the composite samples generally were higher the day after a wet-weather event compared to dry-weather composite samples and other wet-weather composite samples collected. In the five Three Rivers sites, median bacteria concentrations 3 days after a wet-weather event in composite samples tended to fall below the water-quality standards and criteria; in the eight tributary sites, median bacteria concentrations in the dry-weather and wet-weather composite samples generally were above the water-quality standards or criteria. Composite samples collected at the upstream sites on the Three Rivers and selected tributaries generally had lower median bacteria concentrations than composite samples collected at the downstream sites during dry- and wet-weather events. Higher concentrations downstream may be because o
Calculating NH3-N pollution load of wei river watershed above Huaxian section using CSLD method

NASA Astrophysics Data System (ADS)

Zhu, Lei; Song, JinXi; Liu, WanQing

2018-02-01

Huaxian Section is the last hydrological and water quality monitoring section of Weihe River Watershed. So it is taken as the research objective in this paper and NH3-N is chosen as the water quality parameter. According to the discharge characteristics of point source pollutions and non-point source pollutions, a new method to estimate pollution loads—characteristic section load (CSLD)method is suggested and point source pollution and non-point source pollution loads of Weihe River Watershed above Huaxian Section are calculated in the rainy, normal and dry season in the year 2007. The results show that the monthly point source pollution loads of Weihe River Watershed above Huaxian Section discharge stably and the monthly non-point source pollution loads of Weihe River Watershed above Huaxian Section change greatly. The non-point source pollution load proportions of total pollution load of NH3-N decrease in the normal, rainy and wet period in turn.
Fish assemblage, density, and growth in lateral habitats within natural and regulated sections of Washington's Elwha River prior to dam removal

USGS Publications Warehouse

Connolly, P.J.; Brenkman, S.J.

2008-01-01

We characterized seasonal fish assemblage, relative density, and growth in river margins above and between two Elwha River dams scheduled for removal. Fish assemblage and relative density differed in the lateral habitats of the middle-regulated and upper-unregulated sections of the Elwha River. Rainbow trout was the numerically dominant salmonid in both sections, with bull trout present in low numbers. Sculpin were common in the middle section, but not detected in the upper section. In 2004, mean length and biomass of age-0 rainbow trout were significantly smaller in the middle section than in the upper section by the end of the growing season (September). In 2005, an earlier emergence of rainbow trout in the middle section (July) compared to the upper section (August) corresponded with warmer water temperatures in the middle section. Despite lower growth, the margins of mainstem units in the middle section supported higher mean areal densities and biomass of age-0 rainbow trout than the up-per section. These results suggest that growth performance of age-0 rainbow trout was lower in the middle section than in the upper section, which could have been a density-dependent response, or a result of poor food production in the sediment-starved regulated section, or both. Based on our findings, we believe that seasonal sampling of river margins within reference reaches is a cost effective and repeatable method for detection of biologically important short- and long-term changes in emergence timing, density, and growth of rainbow trout before and after dam removals in the Elwha River.
Rainfall threshold definition using an entropy decision approach and radar data

NASA Astrophysics Data System (ADS)

Montesarchio, V.; Ridolfi, E.; Russo, F.; Napolitano, F.

2011-07-01

Flash flood events are floods characterised by a very rapid response of basins to storms, often resulting in loss of life and property damage. Due to the specific space-time scale of this type of flood, the lead time available for triggering civil protection measures is typically short. Rainfall threshold values specify the amount of precipitation for a given duration that generates a critical discharge in a given river cross section. If the threshold values are exceeded, it can produce a critical situation in river sites exposed to alluvial risk. It is therefore possible to directly compare the observed or forecasted precipitation with critical reference values, without running online real-time forecasting systems. The focus of this study is the Mignone River basin, located in Central Italy. The critical rainfall threshold values are evaluated by minimising a utility function based on the informative entropy concept and by using a simulation approach based on radar data. The study concludes with a system performance analysis, in terms of correctly issued warnings, false alarms and missed alarms.
Overview of the Colorado River Canyon from the helicopter pad. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Overview of the Colorado River Canyon from the helicopter pad. View of the Nevada side where new bridge will cross canyon, view northwest - Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark County, NV
2. VIEW OF NORTH FACE SHOWING SUBSTRUCTURE AND ABUTMENTS OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW OF NORTH FACE SHOWING SUBSTRUCTURE AND ABUTMENTS OF BRIDGE CROSSING THE SOUTH FORK OF THE TUOLUMNE RIVER. - South Fork Tuolumne River Bridge, Spanning South Fork Tuolumne River on Tioga Road, Mather, Tuolumne County, CA
77 FR 1020 - Regulated Navigation Area; S99 Alford Street Bridge Rehabilitation Project, Mystic River, MA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-09

...-AA11 Regulated Navigation Area; S99 Alford Street Bridge Rehabilitation Project, Mystic River, MA... Mystic River under and surrounding the S99 Alford Street Bridge which crosses the Mystic River between... construction workers by restricting vessel traffic during periods where the bridge is being repaired. DATES...

Preliminary report on near-surface lignite occurrences, Cleveland County, Arkansas

USGS Publications Warehouse

Heermann, Stephen E.

1983-01-01

Four cross sections were constructed from lithologic descriptions of 43 drill holes in Cleveland County, Ark., in order to illustrate the occurrence of lignite and to relate the lignite beds to the regional stratigraphic framework. Of 43 holes drilled, 8 contained beds of lignite, but only two had beds greater than 30 in. thick. These beds are apparently lenticular and are restricted to the upper 60 ft. of the Cockfield Formation of the Claiborne Group of Middle Eocene age. The Cockfield Formation is at or near the surface west of the Saline River.
21. COMPLETION OF INTAKE CONDUITS REVISED, PIPE SECTIONS AND PLANS, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. COMPLETION OF INTAKE CONDUITS REVISED, PIPE SECTIONS AND PLANS, SHEET 117 OF 117, 1922. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA
Academic Staff Utilization of Information and Communication Technology and Knowledge Creation in Cross River State Universities

ERIC Educational Resources Information Center

Ekpoh, Uduak Imo; Etor, Comfort Robert

2012-01-01

This study examined academic staff utilization of Information and Communication Technology (ICT) in knowledge creation in universities in Cross River State. The study was guided by two research questions and one hypothesis. A questionnaire was developed, validated and used for data collection from a sample of 300 academic staff. Descriptive…
Marketing Strategies and Students' Enrolment in Private Secondary Schools in Calabar Municipality, Cross River State, Nigeria

ERIC Educational Resources Information Center

Uchendu, Chika C.; Nwafor, Innocent A.; Nwaneri, Mary G.

2015-01-01

The study investigated marketing strategies and students' enrolment in private secondary schools in Calabar Municipality, Cross River State. One research question was raised and two null hypotheses formulated to guide the study. Thirty two (32) school administrators in 32 private secondary schools in the study area constitute the study population…
Prevalence, Causes and Effects of Bullying in Tertiary Institutions in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ada, Mary Juliana; Okoli, Georgina; Obeten, Okoi Okorn; Akeke, M. N. G.

2016-01-01

This research is an evaluation of the impact of causes, consequences and effects of bullying in academic setting on student academic performance in tertiary institutions in Cross River State, Nigeria. The research made use of purposive and random sampling techniques made up of 302 students. Questionnaire served as the data collection instrument.…
Teacher Factors and Perceived Assessment Practices Needs of Social Studies Teachers in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ekuri, Emmanuel Etta; Egbai, Julius Michael; Ita, Caroline Iserome

2011-01-01

This study evaluated perceived assessment practices needs among social studies teachers in Cross River State, Nigeria, in relation to some teacher factors (attitude towards social studies, sex, teaching experience and educational qualification). Subjects who participated in this study were 297 social studies teachers (144 males and 153 females)…
Study on the Flexibility in Cross-Border Water Resources Cooperation Governance

NASA Astrophysics Data System (ADS)

Liu, Zongrui; Wang, Teng; Zhou, Li

2018-02-01

Flexible strategy is very important to cross-border cooperation in international rivers water resources, which may be employed to reconcile contradictions and ease conflicts. Flexible characters of cross-border cooperation in international rivers water resources could be analyzed and revealed, using flexible strategic management framework, by taking international cooperation protocols related to water from Transboundary Freshwater Disputes Database (TFDD) as samples from the number of cooperation issues, the amount of management layers and regulator agencies in cooperation organization and the categories of income (cost) distribution (allocation) mode. The research demonstrates that there are some flexible features of cross-border cooperation in international rivers water resources: Riparian countries would select relative diversification strategies related to water, tend to construct a flexible cooperation organization featured with moderate hierarchies from vertical perspective and simplified administrations from horizontal perspective, and adopt selective inducement modes to respect ‘joint and several liability’.
The human role in changing river channels

NASA Astrophysics Data System (ADS)

Gregory, K. J.

2006-09-01

Direct consequences of the human role, where human activity affects river channels through engineering works including channelization, dam construction, diversion and culverting, have been long recognised [Marsh, G.P., 1864. Man and Nature or Physical Geography as Modified by Human Action. Charles Scribner, New York; Thomas Jr., W.L., (ed.) 1956. Man's Role in Changing the Face of the Earth. Chicago, University of Chicago Press, Chicago.]. The less obvious indirect effects of point and reach changes occurring downstream and throughout the basin, however, are much more recently appreciated, dating from key contributions by Strahler [Strahler, A.N., 1956. The nature of induced erosion and aggradation. In W. L. Thomas (Ed.), Man's Role in Changing the Face of the Earth. University of Chicago Press, Chicago, 621-638.], Wolman [Wolman, M.G., 1967. A cycle of sedimentation and erosion in urban river channels. Geografiska Annaler 49A, 385-95.], Schumm [Schumm, S.A., 1969. River metamorphosis. Proceedings American Society of Civil Engineers, Journal Hydraulics Division 95, 255-73.], and Graf [Graf, W.L., 1977. The rate law in fluvial geomorphology. American Journal of Science, 277, 178-191.]. These are complemented by effects of alterations of land use, such as deforestation, intensive agriculture and incidence of fire, with the most extreme effects produced by building activity and urbanisation. Changing river channels are most evident in the channel cross-section where changes of size, shape and composition are now well-established, with up to tenfold increases or decreases illustrated by results from more than 200 world studies. In addition the overall channel planform, the network and the ecology have changed. Specific terms have become associated with changing river channels including enlargement, shrinkage and metamorphosis. Although the scope of adjustment has been established, it has not always been possible to predict what will happen in a particular location, because of complex response and contingency. The ways in which changes in cross-section relate to reach and network changes are less clear, despite investigations showing the distribution of changes along segmented channels. When considering the human role in relation to changing river channels, at least five challenges persist. First, because prediction of the nature and amount of likely change at a particular location is not certain, and because the contrasting responses of humid and arid systems needs to be considered, modelling is required to reduce uncertainty, as was first emphasised by Burkham [Burkham, D.E., 1981. Uncertainties resulting from changes in river form. American Society Civil Engineers Proceedings, Journal Hydraulics Division 107, 593-610.]. Second, feedback effects incorporated within the relationship between changes at channel, reach and network scales can have considerable implications, especially because changes now evident may have occurred, or have been initiated, under different environmental conditions. Third, consideration of global climate change is imperative when considering channel sensitivity and responses to threshold conditions. Fourth, channel design involving geomorphology should now be an integral part of restoration procedures. This requires, fifthly, greater awareness of different cultures as a basis for understanding constraints imposed by legislative frameworks. Better understanding of the ways in which the perception of the human role in changing river channels varies with culture as well as varying over time should enhance application of design for river channel landscapes.
15. OVERVIEW OF TULE RIVER POWERHOUSE FROM FLUME SECTION JUST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. OVERVIEW OF TULE RIVER POWERHOUSE FROM FLUME SECTION JUST SOUTHEAST OF FOREBAY SHOWING BYPASSED SEGMENT OF OLD HIGHWAY 190 IN FRONT OF POWERHOUSE A PHOTO RIGHT CENTER. TAILRACE FROM POWERHOUSE DISCHARGES PROJECT WATER BACK INTO TULE RIVER MIDDLE FORK JUST OUT OF VIEW AT EXTREME LEFT OF PHOTO. VIEW TO SOUTHWEST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA
The development and evolution of landform based on neotectonic movement: The Sancha river catchment in the southwestern China

NASA Astrophysics Data System (ADS)

Zhong, Lingmin; Xu, Mo; Yang, Yanna; Wang, Xingbing

2018-02-01

Neotectonics has changed the coupled process of endogenic and exogenic geological dynamics, which mold the modern landform. Geomorphologic analysis is essential for identifying and understanding the tectonic activity and indicates the responsive mechanism of the landform to tectonic activity. At first, this research reconstructed the twisted Shanpen period planation surface, computed the valley floor width-to-height ratio of Sancha river and extracted the cross sections marking the river terraces to analyze the characteristics of the neotectonics. And then, the relation between neotectonic movement and landform development was analyzed by dividing the landform types. At last, the spatial variation of landform evolution was analyzed by extracting the Hypsometric Integral of sub-catchments. The Sancha river catchment's neotectonic movement presents the tilt-lift of earth's crust from NW to SE, which is characterized by the posthumous activity of Yanshan tectonic deformation. The spatial distribution of river terraces indicates that Sancha river catchment has experienced at least four intermittent uplifts and the fault blocks at both the sides of Liuzhi-Zhijin basement fault have differentially uplifted since the late Pleistocene. As the resurgence of Liuzhi-Zhijin basement fault, the Sancha river catchment was broken into two relative independent landform units. The spatial variations of the landform types near the Sancha river and the sub-catchments' landform evolution are characterized by periodic replacement. The styles of geological structure have controlled the development of landform far away from the Sancha River and influenced the landform evolution. The posthumous activities of the secondary structure have resulted in the spatial variation of sub-catchments' landform evolution, which presents periodic replacement with local exceptions. The present study suggests that spatial variations of the development and evolution of modern landform of Sancha River catchment owe their genesis to the interplay between the hydrodynamic force and tectonic activity in the neotectonic period. Likewise, the application of geomorphic indicators also provides a new way to assess the regional crustal stability.
Derivation and Application of Idealized Flow Conditions in River Network Simulation

NASA Astrophysics Data System (ADS)

Afshari Tork, S.; Fekete, B. M.

2015-12-01

Stream flow information is essential for many applications across broad range of scales, e.g. global water balances, engineering design, flood forecasting, environmental management, etc. Quantitative assessment of flow dynamics of natural streams, requires detailed knowledge of all the geometrical and geophysical variables (e.g. bed-slope, bed roughness, etc.) along river reaches. Simplifying the river bed geometries could reduce both the computational burden implementing flow simulations and challenges in assembling the required data, especially for large domains. Average flow conditions expressed as empirical "at-a-station" hydraulic geometry relationships between key channel components, (i.e. water depth, top-width, flow velocity, flow area against discharge) have been studied since 60's. Recent works demonstrated that power-function as idealized riverbed geometry whose parameters are correlated to those of exponential relationship between mean water depth and top-width, are consistent with empirical "at-a-station" relations.US Geological Surveys' National Water Information System web-interface provides huge amount of river discharge and corresponding stage height data from several thousands of streamflow monitoring stations over United States accompanied by river survey summaries providing additional flow informations (width, mean velocity, cross-sectional area). We conducted a series of analyses to indentify consistent data daily monitoring and corresponding survey records that are suitable to refine our current understanding of how the "at-a-station" properties of river channels relate to channel forming characteristics (e.g. riverbed slope, flow regime, geology, etc.). The resulting ~1,200 actively operating USGS stations with over ~225,000 corresponding survery records (almost 200 survey per gauge on average) is the largest river survey database ever studied in the past.Our presentation will show our process assembling our river monitoring and survey data base and we will present our first results translating "at-a-station" relations into he hydraulic geometry of river channels based on idealized power-law riverbed geometries. We also will also present a series of application (e.g. improved flow rounting, simplyfied river surveying).
Plan form changes of Gumara River channel over 50 years (Upper Blue Nile basin, Ethiopia)

NASA Astrophysics Data System (ADS)

Abate, Mengiste; Nyssen, Jan; Mehari, Michael

2014-05-01

Channel plan form changes were investigated along the 65 km long Gumara River in Lake Tana basin (Ethiopia) by overlaying information from aerial photographs and SPOT imagery. Two sets of aerial photographs (1957 and 1980) were scanned, and then orthorectified in ENVI 4.2 environment. Recent channel plan form information was extracted from SPOT images of 2006. ERDAS 2010 and ArcGIS 10.1 tools were used for the data preparation and analysis. The information on river plan form changes spans from 1957 to 2006 (49 years), during which time the Gumara catchment has been subjected to changes in land use/cover and increasing water abstraction, which may have affected its hydrogeomorphology. The results indicated that the lower reach of Gumara at its mouth has undergone major plan form changes. A delta of 1.12 km² was created between 1957 and 1980 and additional 1.00 km² land has been created between 1980 and 2006. The sinuosity of the plan form changed only slightly through the study period: 1.78 in 1957, 1.76 in 1980, and 1.81 in 2006. Comparison of cross sections at the hydrological gauging station showed that the river bed aggraded in the order of 1.5 m to 2.5 m for the period 1963-2009. The trend analysis of stream flow of Gumara River versus rainfall in the catchment also indicated that the bed level of the Gumara river at its gauging station has risen. From field observations, the impact of direct human interventions was identified. The building of artificial levees along the river banks has contributed to huge deposition in the river bed. At locations where intensive irrigation takes place in the floodplain, seepage water through the banks created river bank failure and modifications in plan form. The unstable segments of the river reach were identified and will be further analysed.
33 CFR 263.13 - Program scope.

Code of Federal Regulations, 2010 CFR

2010-07-01

... authority. Section 107, River and Harbor Act of 1960, as amended (33 U.S.C 577). (e) Authority for snagging and clearing for navigation. Section 3, River and Harbor Act of 1945 (33 U.S.C 603a). (f) Small beach erosion control project authority. Section 103, River and Harbor Act of 1962, as amended (33 U.S.C. 426g...
Numerical Estimation of the Outer Bank Resistance Characteristics in AN Evolving Meandering River

NASA Astrophysics Data System (ADS)

Wang, D.; Konsoer, K. M.; Rhoads, B. L.; Garcia, M. H.; Best, J.

2017-12-01

Few studies have examined the three-dimensional flow structure and its interaction with bed morphology within elongate loops of large meandering rivers. The present study uses a numerical model to simulate the flow pattern and sediment transport, especially the flow close to the outer-bank, at two elongate meandering loops in Wabash River, USA. The numerical grid for the model is based on a combination of airborne LIDAR data on floodplains and the multibeam data within the river channel. A Finite Element Method (FEM) is used to solve the non-hydrostatic RANS equation using a K-epsilon turbulence closure scheme. High-resolution topographic data allows detailed numerical simulation of flow patterns along the outer bank and model calibration involves comparing simulated velocities to ADCP measurements at 41 cross sections near this bank. Results indicate that flow along the outer bank is strongly influenced by large resistance elements, including woody debris, large erosional scallops within the bank face, and outcropping bedrock. In general, patterns of bank migration conform with zones of high near-bank velocity and shear stress. Using the existing model, different virtual events can be simulated to explore the impacts of different resistance characteristics on patterns of flow, sediment transport, and bank erosion.
15. 'Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. 'Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, California, A.J. Logan, County Surveyor, H.J. Brunnier, Consulting Engineer, March 7, 1919,' showing general plan, plan of top chord, elevation of main girder, transverse section, plan section at deck level. - Salt River Bridge, Spanning Salt River at Dillon Road, Ferndale, Humboldt County, CA
Water quality in the tidal Potomac River and Estuary, hydrologic data report, 1979 water year

USGS Publications Warehouse

Blanchard, Stephen F.; Hahl, D.C.

1981-01-01

This report contains data on the physical and chemical properties measured during the 1979 water year for the tidal Potomac River and estuary. Data were collected routinely at five major stations and periodically at 14 intervening stations. Each major station represents a cross section through which the transport of selected dissolved and suspended materials will be computed. The intervening stations represent locations at which data were collected for special studies such as: salt water migration, dissolved oxygen dynamics, and other synoptic studies. About 960 samples were analyzed for silicate, Kjeldhal nitrogen, nitrite, phosphorus, chlorophyll and suspended sediment, with additional samples analyzed for organic carbon, calcium, magnesium, sodium, bicarbonate, sulfate, potassium, chloride, fluoride, seston and dissolved solids residue. In addition, about 1400 in-situ measurements of dissolved oxygen, specific conductance, temperature, and Secchi disk transparency are reported. (USGS)
Hydraulic analysis of Chenango River, Broome County, New York in relation to state highway plan

USGS Publications Warehouse

Dunn, Bernard

1981-01-01

Hydraulic analyses of the 50- and 100-year floods in a 3.2 mile reach of the Chenango River in the towns of Fenton and Chenango in New York were made to determine the effects of two alternative bridge designs on flood levels. Neither design would cause more than a 0.1-foot increase in water level of the 50-year flood nor more than a 0.2-foot increase in water level of the 100-year flood above levels that would occur during these floods under present channel conditions. The discharges used in the analyses were 55,200 cubic feet per second for the 50-year flood and 63,000 cubic feet per second for the 100-year flood. Mean flow velocities and water-surface elevations at 17 cross sections are given for both bridge designs and are compared with those that would occur under present conditions. (USGS)
Surface-water-quality assessment of the Kentucky River Basin, Kentucky; fixed-station network and selected water-quality data, April 1987 through August 1991

USGS Publications Warehouse

Griffin, M.S.; Martin, G.R.; White, K.D.

1994-01-01

This report describes selected data-collection activities and the associated data collected during the Kentucky River Basin pilot study of the U.S. Geological Survey's National Water-Quality Assessment Program. The data are intended to provide a nationally consistent description and improved understanding of current water quality in the basin. The data were collected at seven fixed stations that represent stream cross sections where constituent transport and water-quality trends can be evaluated. The report includes descriptions of (1) the basin; (2) the design of the fixed-station network; (3) the fixed-station sites; (4) the physical and chemical measurements; (5) the methods of sample collection, processing, and analysis; and (6) the quality-assurance and quality-control procedures. Water-quality data collected at the fixed stations during routine periodic sampling and supplemental high-flow sampling from April 1987 to August 1991 are presented.
36 CFR 7.71 - Delaware Water Gap National Recreation Area.

Code of Federal Regulations, 2014 CFR

2014-07-01

... of L. R. 45012 (commonly known as the River Road). Loop Two is approximately 6 miles long and begins at the northwest end of Loop One; it goes northeasterly between the Delaware River and River Road for about one mile until it crosses River Road; then southwesterly along the ridge which is south of Hidden...
36 CFR 7.71 - Delaware Water Gap National Recreation Area.

Code of Federal Regulations, 2012 CFR

2012-07-01

... of L. R. 45012 (commonly known as the River Road). Loop Two is approximately 6 miles long and begins at the northwest end of Loop One; it goes northeasterly between the Delaware River and River Road for about one mile until it crosses River Road; then southwesterly along the ridge which is south of Hidden...

36 CFR 7.71 - Delaware Water Gap National Recreation Area.

Code of Federal Regulations, 2010 CFR

2010-07-01

... of L. R. 45012 (commonly known as the River Road). Loop Two is approximately 6 miles long and begins at the northwest end of Loop One; it goes northeasterly between the Delaware River and River Road for about one mile until it crosses River Road; then southwesterly along the ridge which is south of Hidden...
36 CFR 7.71 - Delaware Water Gap National Recreation Area.

Code of Federal Regulations, 2013 CFR

2013-07-01

... of L. R. 45012 (commonly known as the River Road). Loop Two is approximately 6 miles long and begins at the northwest end of Loop One; it goes northeasterly between the Delaware River and River Road for about one mile until it crosses River Road; then southwesterly along the ridge which is south of Hidden...
36 CFR 7.71 - Delaware Water Gap National Recreation Area.

Code of Federal Regulations, 2011 CFR

2011-07-01

... of L. R. 45012 (commonly known as the River Road). Loop Two is approximately 6 miles long and begins at the northwest end of Loop One; it goes northeasterly between the Delaware River and River Road for about one mile until it crosses River Road; then southwesterly along the ridge which is south of Hidden...
Evaluating a Radar-Based, Non Contact Streamflow Measurement System in the San Joaquin River at Vernalis, California

USGS Publications Warehouse

Cheng, Ralph T.; Gartner, Jeffrey W.; Mason, Jr., Robert R.; Costa, John E.; Plant, William J.; Spicer, Kurt R.; Haeni, F. Peter; Melcher, Nick B.; Keller, William C.; Hayes, Ken

2004-01-01

Accurate measurement of flow in the San Joaquin River at Vernalis, California, is vital to a wide range of Federal and State agencies, environmental interests, and water contractors. The U.S. Geological Survey uses a conventional stage-discharge rating technique to determine flows at Vernalis. Since the flood of January 1997, the channel has scoured and filled as much as 20 feet in some sections near the measurement site resulting in an unstable stage-discharge rating. In response to recent advances in measurement techniques and the need for more accurate measurement methods, the Geological Survey has undertaken a technology demonstration project to develop and deploy a radar-based streamflow measuring system on the bank of the San Joaquin River at Vernalis, California. The proposed flow-measurement system consists of a ground-penetrating radar system for mapping channel geometries, a microwave radar system for measuring surface velocities, and other necessary infrastructure. Cross-section information derived from ground penetrating radar provided depths similar to those measured by other instruments during the study. Likewise, surface-velocity patterns and magnitudes measured by the pulsed Doppler radar system are consistent with near surface current measurements derived from acoustic velocity instruments. Since the ratio of surface velocity to mean velocity falls to within a small range of theoretical value, using surface velocity as an index velocity to compute river discharge is feasable. Ultimately, the non-contact radar system may be used to make continuous, near-real-time flow measurements during high and medium flows. This report documents the data collected between April 14, 2002 and May 17, 2002 for the purposes of testing this radar based system. Further analyses of the data collected during this field effort will lead to further development and improvement of the system.
Politics of Leadership and Implementation of Educational Policies and Programmes of Tertiary Institutions in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ekpiken, W. E.; Ifere, Francis O.

2015-01-01

This paper examines issues of politics of leadership and implementation of Educational policies and programmes of tertiary institutions in Cross River State with a view to determine the problems are situated and suggest the way forward. It examines the concept of politics of education, concept of leadership, meaning of planning and generation of…
Assessing Teaching Readiness of University Students in Cross River State, Nigeria: Implications for Managing Teacher Education Reforms

ERIC Educational Resources Information Center

Akuegwu, B. A.; Edet, A. O.; Uchendu, C. C.; Ekpoh, U. I.

2011-01-01

This ex-post-facto designed study was geared towards assessing the readiness of would-be teachers in universities in Cross River State for the teaching profession, and how reforms can be managed to strengthen this. Three hypotheses were isolated to give direction to this investigation. 200 students from the two universities in the state…
Resource Availability and Distribution in Public and Private Special Education Schools in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ntukidem, Peter James; Ntukidem, Eno Peter; Eyo, Eno Etudor

2011-01-01

This study investigated the availability and distribution of staff and facilities/equipment in private and public special needs schools in Cross River State. Sixty-nine (69) teachers and three (3) principals of these schools constituted the sample size of the study. One hypothesis and one research question were postulated to guide the study. The…
"Broken-Off Like Limbs from a Tree": Fractured Identity in Caryl Phillips's "Crossing the River (1993)"

ERIC Educational Resources Information Center

Labidi, Abid Larbi

2016-01-01

My major purpose in studying Caryl Phillips's widely acclaimed novel "Crossing the River" is to examine, through a close textual analysis, the severe identity crisis inflicted upon slaves under the three-century long slavery institution. I explore how slaves' tragic rift of separation from their African homelands led to a disastrous loss…
Entrepreneurship Education and Career Intentions of Tertiary Education Students in Akwa Ibom and Cross River States, Nigeria

ERIC Educational Resources Information Center

Ekpoh, Uduak Imo; Edet, Aniefiok Oswald

2011-01-01

This paper explores the impact of entrepreneurship education on career intentions among 500 students drawn from two universities in Akwa Ibom and Cross River States of Nigeria. The study adopted a survey design. Two research questions and two hypotheses were raised for the study. Data were collected using a structured questionnaire titled…
Public Perception of the Millennium Development Goals on Access to Safe Drinking Water in Cross River State, Nigeria

ERIC Educational Resources Information Center

Eni, David D.; Ojong, William M.

2014-01-01

This study evaluated the public perception of Millennium Development Goals (MDGs) of environmental sustainability with focus on the MDG target which has to do with reducing the proportion of people without access to safe drinking water in Cross River State, Nigeria. The stratified and systematic sampling techniques were adopted for the study,…
Western and Traditional Educational Background of Midwives and Delivery Pain Control among Women in Cross River State, Nigeria

ERIC Educational Resources Information Center

Oyira, Emilia James; Emon, Umoe Duke; Essien, N. C.; Ekpenyong, Affiong Onoyom

2015-01-01

This study sought to investigate western and traditional educational background of midwives with regard to their effectiveness in delivery pain control in Cross River State-Nigeria. To achieve this purpose, two null hypotheses were formulated to guide the investigation. The study adopted the survey design. The sample consisted of 360 post-natal…
The Cretaceous-Paleogene boundary in the Brazos River area (Texas): new sections and revised interpretations

NASA Astrophysics Data System (ADS)

Hart, M.; Leighton, A.; Yancey, T.; Miller, B.; Smart, C.; Twitchett, R.

2012-04-01

The Brazos River area of Texas is famous for outcrops of the K/Pg transition and lowermost Paleocene strata. A number of new, un-described sections have been investigated and they provide biostratigraphical and sedimentological information on the events preceding, during and following the Chixculub impact event. The mudstones of the Corsicana Formation (Maastrichtian) contain a number of very thin volcanic ashes, including the yellow/white gypsum-rich horizon incorrectly regarded by some workers as evidence of a pre-K/Pg boundary impact. The mudstones of the Corsicana Mudstone Fm (uppermost Maastrichtian) were significantly eroded by the end-Cretaceous tsunami and the surficial unconsolidated muds as well as a thickness of lithified mudstone eroded and put into suspension, thereby providing the reworked Cretaceous assemblages of microfossils recorded by a number of authors. Erosional relief on the 75-100 m deep sea floor is visible in Cottonmouth Creek and the new River Bank South section as a series of ridges and erosional troughs, trending NW-SE. Trough lows are in-filled with mud-matrix mass flow deposits containing large blocks of Maastrichtian mudstones and transported concretions. These are overlain with granular shell-rich sediments containing spherules, fish teeth, bone fragments and re-worked foraminifera and hummocky cross-stratified storm sands with mudstone inter-beds. Sea floor ridges remained exposed to open marine waters and were colonized with a thin oyster pavement before burial by Kincaid Formation mudstones and siltstones. A return to quiet water conditions during the earliest Paleocene is recorded in a new 3-6 m section of foraminifera-rich mudstones, siltstones and sandstones bounded above and below with zones of carbonate and pyrite concretions, best seen in the River bank South section. The foraminiferal sand unit contains steinkerns and phosphatic concretions indicative of a condensed deposit. The P1a/P1b zonal boundary lies near the top of these foraminiferal sands. Our investigations for the foraminifera and other microfossils from these successions are on-going and the newly discovered volcanic ashes are being investigated and dated. The timing of the events at the K/Pg boundary in Texas can be correlated with the successions in Denmark (Stevns Klint) and the Atlantic Ocean (e.g., Demerara Rise), thereby giving an holistic picture of the end-Cretaceous events.
Spatial and temporal genetic analysis of Walleyes in the Ohio River

USGS Publications Warehouse

Page, Kevin S.; Zweifela, Richard D.; Stott, Wendylee

2017-01-01

Previous genetic analyses have shown that Walleyes Sander vitreus in the upper Ohio River comprise two distinct genetic strains: (1) fish of Great Lakes origin that were stocked into the Ohio River basin and (2) a remnant native strain (Highlands strain). Resource agencies are developing management strategies to conserve and restore the native strain within the upper reaches of the Ohio River. Hybridization between strains has impacted the genetic integrity of the native strain. To better understand the extent and effects of hybridization on the native strain, we used mitochondrial DNA and microsatellite markers to evaluate the spatial (river sections) and temporal (pre- and poststocking) genetic diversity of Ohio River Walleyes. Contemporary Lake Erie Walleyes and archival museum specimens collected from the Ohio River basin were used for comparison to contemporary Ohio River samples. Although there was evidence of hybridization between strains, most of the genetic diversity within the Ohio River was partitioned by basin of origin (Great Lakes versus the Ohio River), with greater similarity among river sections than between strains within the same section. Results also suggested that the native strain has diverged from historical populations. Furthermore, notable decreases in measures of genetic diversity and increased relatedness among native-strain Walleyes within two sections of the Ohio River may be related to stocking aimed at restoration of the Highlands strain. Our results suggest that although the Highlands strain persists within the Ohio River, it has diverged over time, and managers should consider the potential impacts of future management practices on the genetic diversity of this native strain.
Hydrometry's classical and Innovative methods and tools comparison for Stara river flows at Agios Germanos monitoring station in north-west Greece.

NASA Astrophysics Data System (ADS)

Filintas, Agathos, , Dr; Hatzigiannakis, Evagellos, , Dr; Arampatzis, George, , Dr; Ilias, Andreas; Panagopoulos, Andreas, , Dr; Hatzispiroglou, Ioannis

2015-04-01

The aim of the present study is a thorough comparison of hydrometry's conventional and innovative methods-tools for river flow monitoring. A case study was conducted in Stara river at Agios Germanos monitoring station (northwest Greece), in order to investigate possible deviations between conventional and innovative methods-tools on river flow velocity and discharge. For this study, two flowmeters were used, which manufac-tured in 2013 (OTT Messtechnik Gmbh, 2013), as follows: a) A conventional propeller flow velocity meter (OTT-Model C2) which is a me-chanical current flow meter with a certification of calibration BARGO, operated with a rod and a relocating device, along with a digital measuring device including an elec-tronic flow calculator, data logger and real time control display unit. The flowmeter has a measurement velocity range 0.025-4.000 m/s. b) An innovative electromagnetic flowmeter (OTT-Model MF pro) which it is con-sisted of a compact and light-weight sensor and a robust handheld unit. Both system components are designed to be attached to conventional wading rods. The electromag-netic flowmeter uses Faraday's Law of electromagnetic induction to measure the process flow. When an electrically conductive fluid flows along the meter, an electrode voltage is induced between a pair of electrodes placed at right angles to the direction of mag-netic field. The electrode voltage is directly proportional to the average fluid velocity. The electromagnetic flowmeter was operated with a rod and relocating device, along with a digital measuring device with various logging and graphical capabilities and vari-ous methods of velocity measurement (ISO/USGS standards). The flowmeter has a measurement velocity range 0.000-6.000 m/s. The river flow data were averaged over a pair measurement of 60+60 seconds and the measured river water flow velocity, depths and widths of the segments were used for the estimation of cross-section's mean flow velocity in each measured segment. Then it was used the mid-section method for the overall discharge calculation of all segments flow area. The cross-section characteristics, the river flow velocity of segments and the mean water flow velocity and discharge total profile were measured, calculated and an-notated respectively. A series of concurrent conventional and innovative (electromag-netic) flow measurements were performed during 2014. The results and statistical analysis showed that Froude number during the measurement period in all cases was Fr<1 which means that the water flow of the Stara river is classified as subcritical flow. The 12 months' study showed various advantages for the elec-tromagnetic sensor that is virtually maintenance-free because there are no moving parts, no calibration was required in practice, and it can be used even in the lowest water ve-locities from 0.000 m/s. Moreover, based on the concurrent hydromeasurements of the Stara River, on the velocity and discharge modelling and the statistical analysis, it was found that there was not a significant statistical difference (α=0.05) between mean velocity measured with a) conventional and b) electromagnetic method which seems to be more accurate in low velocities where a significant statistical difference was found. Acknowledgments Data in this study are collected in the framework of the elaboration of the national water resources monitoring network, supervised by the Special Secretariat for Water-Hellenic Ministry for the Environment and Climate Change. This project is elaborated in the framework of the operational program "Environment and Sustainable Development" which is co-funded by the National Strategic Reference Framework (NSRF) and the Public Investment Program (PIP).
Bedload pulses in a hydropower affected alpine gravel bed river

NASA Astrophysics Data System (ADS)

Aigner, Johann; Kreisler, Andrea; Rindler, Rolf; Hauer, Christoph; Habersack, Helmut

2017-08-01

This study investigated the sediment resupply and transport dynamics at the Upper Drau River upstream of Lienz (Eastern Tyrol, Austria). Due to a hydropower plant, a 24 km long river reach of this alpine gravel bed river is under residual flow conditions, although sediment is still resupplied into the reach through many active torrents and tributaries. As a result, sediment deposition in the residual flow reach intensified, hence increasing maintenance efforts to stabilize this river section and ensure flood protection. In combination with a new sediment management program, a continuous bedload monitoring system was installed 2 km downstream of the residual reach in 2001 to support the development of adapted sediment management strategies. The surrogate bedload monitoring system consists of 16 impact plate geophones, installed over a 17 m wide cross section. The unprecedented 15-year dataset of high-resolution bedload intensity revealed a complex process of gravel storage and intermittent resupply from the residual reach, allowing the authors a detailed analysis of frequently occurring bedload pulses. These transport features are triggered by increased discharges during floods in the residual reach and created pronounced anticlockwise bedload hysteresis or, with a temporal shift to the event peak, caused distinct shifts in the bedload activity downstream. Bedload pulses produce very high bedload fluxes while in transit, tend to increase bedload flux in the post-event phase, and can alter and reduce the upstream sediment storage leading to a lowering of bedload availability for future pulses. The observed time lags between main discharge events and the arrival of the macro-pulses are correlated with mean water discharge during pulse propagation, thus enabling a prediction of the pulse arrival at the monitoring station solely based on the hydrograph. In combination with the hydrological setup of the reach, the observed bedload pulse time lags allowed an estimation of pulse velocities in the range 0.002 - 0.05 m s- 1.
Determination of mass balance and entrainment in the stratified Duwamish River Estuary, King County, Washington

USGS Publications Warehouse

Stoner, J.D.

1972-01-01

During a study of the effects of waste-water input on the stratified Duwamish River estuary, intensive water-velocity and salinity measurements were made in both the lower salt wedge and the upper fresher water layer for tidal-cycle periods. The net movement of water and salt mass past a cross section during a tidal cycle was determined from integration of the measured rates of movement of water and salt past the section. The net volume of water that moved downstream past the section during the cycle agreed with the volume of fresh-water inflow at the head of the estuary within (1) 3.8 and 7.2 percent, respectively, for two studies made during periods of maximum and minimum tidal-prism thickness and identical inflow rates .of 312 cfs (cubic feet per second), and (2) 15 percent for one study made during a period of average tidal-prism thickness and an inflow rate of 1,280 cfs. For the three studies, the difference between salt mass transported upstream and downstream during the cycles ranged from 0.8 to 19 percent of the respective mean salt-mass transport. Water was entrained from the .salt-water wedge into the overlying layer of mixed fresh and salt water at tidal-cycle-average rates of 30 and 69 cfs per million square feet of interface for the inflow rates of 312 cfs, and 99 cfs per million square feet of interface for an inflow rate of 1,280 cfs. At a constant inflow rate, the rate of entrainment of salt-wedge water in the Duwamish River estuary more than doubled for a doubling of tidal-prism thickness. It also doubled for a quadrupling of inflow rate at about constant tidal-prism thickness.
The geologic story of the Great Plains

USGS Publications Warehouse

Trimble, Donald E.

1980-01-01

For more than half a century after Lewis and Clark crossed the country in 1805-6, the Great Plains was the testing ground of frontier America here America grew to maturity (fig. 1). In 1805-7, explorer Zebulon Pike crossed the southcentral Great Plains, following the Arkansas River from near Great Bend, Kans., to the Rocky Mountains. In later years, Santa Fe traders, lured by the wealth of New Mexican trade, followed Pike's path as far as Bents Fort, Colo., where they turned southwestward away from the river route. Those pioneers who later crossed the plains on the Oregon Trail reached the Platte River near the place that would become Kearney, Nebr., by a nearly direct route from Independence, Mo., and followed the Platte across the central part of the Great Plains.
Trace element fluxes in sediments of an environmentally impacted river from a coastal zone of Brazil.

PubMed

da Silva, Yuri Jacques Agra Bezerra; Cantalice, José Ramon Barros; Singh, Vijay P; do Nascimento, Clístenes Williams Araújo; Piscoya, Victor Casimiro; Guerra, Sérgio M S

2015-10-01

Data regarding trace element concentrations and fluxes in suspended sediments and bedload are scarce. To fill this gap and meet the international need to include polluted rivers in future world estimation of trace element fluxes, this study aimed to determine the trace element fluxes in suspended sediment and bedload of an environmentally impacted river in Brazil. Water, suspended sediment, and bedload from both the upstream and the downstream cross sections were collected. To collect both the suspended sediment and water samples, we used the US DH-48. Bedload measurements were carried out using the US BLH 84 sampler. Concentrations of Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn were determined by inductively coupled plasma (ICP-OES). As and Hg were determined by an atomic absorption spectrophotometer (AA-FIAS). The suspended sediments contributed more than 99 % of the trace element flux. By far Pb and to a less extent Zn at the downstream site represents major concerns. The yields of Pb and Zn in suspended sediments were 4.20 and 2.93 kg km(2) year(-1), respectively. These yields were higher than the values reported for Pb and Zn for Tuul River (highly impacted by mining activities), 1.60 and 1.30 kg km(2) year(-1), respectively, as well as the Pb yield (suspended + dissolved) to the sea of some Mediterranean rivers equal to 3.4 kg km(2) year(-1). Therefore, the highest flux and yield of Pb and Zn in Ipojuca River highlighted the importance to include medium and small rivers-often overlooked in global and regional studies-in the future estimation of world trace element fluxes in order to protect estuaries and coastal zones.
Geologic history of the Colorado River: Chapter C in The Colorado River region and John Wesley Powell (Professional Paper 669)

USGS Publications Warehouse

Hunt, Charles B.

1969-01-01

John Wesley Powell clearly recognized that the spectacular features of the Colorado River - its many grand canyons - were dependent upon the structural history of the mountainous barriers crossed by the river. He conceived of three different historical relationships between rivers and structural features: (1) Newly uplifted land surfaces have rivers that flow down the initial slope of the uplift; these relationships he termed consequent. (2) A river may be older than an uplift that it crosses because it has been able to maintain its course by eroding downward as the uplift progresses; this relationship he named antecedent. (3) An uplifted block may have been buried by younger deposits upon which a river becomes established. The river, in cutting downward, uncovers the uplifted block and becomes incised into it; this relationship he called superimposed.The geologic history of the Colorado River involves all three relationships. In addition, although the position of the river course through a particular structural barrier may have been the result of superposition, the depth of the canyon at that point may be largely due to renewed uplift of the barrier; such deepening of the canyon, therefore, is due to antecedence. The problem of the Colorado River remains today very much as G. K. Gilbert stated it nearly 100 years ago: "How much is antecedent and how much is superimposed?" The question must be asked separately for each stretch of the river.
[Distribution of Diatoms in Main Sections of Urban District Rivers with Drowning-prone in Chengdu].

PubMed

Ni, Z X; Xie, Q; Yi, X F

2016-10-01

To explore the species distribution and constituent ratio of diatoms in main sections of urban district rivers where drowning occurs frequently in Chengdu. Total 39 water samples from the sampling points of 5 rivers （Jinjiang, Jinniu, Qingyang, Wuhou and Chenghua districts） in October 2014 were collected. The diatoms smear were made and the species distribution and constituent ratio of diatoms from the water samples were analyzed using biological microscope and acquisition system of digital microscope. Total 21 species of diatoms were detected in main sections of urban district rivers in Chengdu. Significant differences in the dominant diatom species and proportions of the different rivers were observed, and there were different species existed in all sampling points of the upstream, midstream and downstream of the rivers. The database of species map, species distribution and constituent ratio of diatoms in main sections of urban district rivers in Chengdu are preliminarily established, which has special meaning for the analysis and evaluation of falling location inference using diatoms test in case investigation. Copyright© by the Editorial Department of Journal of Forensic Medicine

Method For Identifying Sedimentary Bodies From Images And Its Application To Mineral Exploration

NASA Technical Reports Server (NTRS)

Wilkinson, Murray Justin (Inventor)

2006-01-01

A method is disclosed for identifying a sediment accumulation from an image of a part of the earth's surface. The method includes identifying a topographic discontinuity from the image. A river which crosses the discontinuity is identified from the image. From the image, paleocourses of the river are identified which diverge from a point where the river crosses the discontinuity. The paleocourses are disposed on a topographically low side of the discontinuity. A smooth surface which emanates from the point is identified. The smooth surface is also disposed on the topographically low side of the point.
Multiple crossings of a large glacial river by Canada Lynx (Lynx canadensis)

Treesearch

D. Feierabend; K. Kielland

2014-01-01

Rivers may act as barriers to the movement of terrestrial mammals, which could limit dispersal and gene flow. Glacial rivers are particularly hazardous because of the cold water temperature and swift current. Yet, we determined that 2 Canada Lynx (Lynx canadensis) equipped with GPS collars repeatedly swam across the main channel of the Tanana River in interior Alaska...
Extent of areal inundation of riverine wetlands along Cypress Creek and the Peace, Alafia, North Prong Alafia, and South Prong Alafia Rivers, west-central Florida

USGS Publications Warehouse

Lewelling, B.R.

2003-01-01

Riverine and palustrine system wetlands are a major ecological component of river basins in west-central Florida. Healthy wetlands are dependent upon the frequency and duration of periodic flooding or inundation. This report assesses the extent, area, depth, frequency, and duration of periodic flooding and the effects of potential surface-water withdrawals on the wetlands along Cypress Creek and the Peace, Alafia, North Prong Alafia, and South Prong Alafia Rivers. Results of the study were derived from step-backwater analysis performed at each of the rivers using the U.S. Army Corps of Engineers Hydrologic Engineering Center-River Analysis System (HEC-RAS) one-dimensional model. The step-backwater analysis was performed using selected daily mean discharges at the 10th, 50th, 70th, 80th, 90th, 98th, 99.5th, and 99.9th percentiles to compute extent of areal inundation, area of inundation, and hydraulic depth to assess the net reduction of areal inundation if 10 percent of the total river flow were diverted for potential withdrawals. The extent of areal inundation is determined by cross-sectional topography and the degree to which the channel is incised. Areal inundation occurs along the broad, low relief of the Cypress Creek floodplain during all selected discharge percentiles. However, areal inundation of the Peace and Alafia Rivers floodplains, which generally have deeply incised channels, occurs at or above discharges at the 80th percentile. The greatest area of inundation along the three rivers generally occurs between the 90th and 98th percentile discharges. The decrease in inundated area resulting from a potential 10-percent withdrawal in discharge ranged as follows: Cypress Creek, 22 to 395 acres (1.7 to 8.4 percent); Peace River, 17 to 1,900 acres (2.1 to 13.6 percent); Alafia River, 1 to 90 acres (1 to 19.6 percent); North Prong Alafia River, 1 to 46 acres (0.7 to 23.4 percent); and South Prong Alafia River, 1 to 75 acres (1.5 to 13.4 percent).
Barriers to and determinants of the use of intermittent preventive treatment of malaria in pregnancy in Cross River State, Nigeria: a cross-sectional study.

PubMed

Ameh, Soter; Owoaje, Eme; Oyo-Ita, Angela; Kabiru, Caroline W; Akpet, Obaji E O; Etokidem, Aniekan; Enembe, Okokon; Ekpenyong, Nnette

2016-05-04

Malaria in pregnancy (MIP) has serious consequences for the woman, unborn child and newborn. The use of sulfadoxine-pyrimethamine for the intermittent preventive treatment of malaria in pregnancy (SP-IPTp) is low in malaria endemic areas, including some regions of Nigeria. However, little is known about pregnant women's compliance with the SP-IPTp national guidelines in primary health care (PHC) facilities in the south-south region of Nigeria. The aim of this study was to identify the barriers to and determinants of the use of SP-IPTp among pregnant women attending ANC in PHC facilities in Cross River State, south-south region of Nigeria. A cross-sectional survey was conducted in 2011 among 400 ANC attendees aged 15-49 years recruited through multistage sampling. Binary logistic regression was used to determine the factors associated with the use of SP-IPTp in the study population. Use of SP-IPTp was self-reported by 41% of the total respondents. Lack of autonomy in the households to receive sulfadoxine-pyrimethamine (SP) during ANC was the main barrier to use of IPTp (83%). Other barriers were stock-outs of free SP (33%) and poor supervision of SP ingestion by directly observed treatment among those who obtained SP from ANC clinics (36/110 = 33%). In the multivariate logistic regression, the odds of using SP-IPTp was increased by the knowledge of the use of insecticide treated nets (ITNs) (OR = 2.13, 95% CI: 1.70-3.73) and SP (OR = 22.13, 95% CI: 8.10-43.20) for the prevention of MIP. Use of ITNs also increased the odds of using SP-IPTp (OR = 2.38, 95% CI: 1.24-12.31). Use of SP-IPTp was low and was associated with knowledge of the use of ITNs and SP as well as the use of ITNs for the prevention of MIP. There is a need to strengthen PHC systems and address barriers to the usage of SP-IPTp in order to reduce the burden of MIP.
Influence of alluvial cover and lithology on the adjustment characteristics of semi-alluvial bedrock channels

NASA Astrophysics Data System (ADS)

Ferguson, Sean P.; Rennie, Colin D.

2017-05-01

A growing body of research has focused on evaluating the adjustment characteristics of semi-alluvial channels containing proximate bedrock, mixed, and alluvial sections. Active orogens have been the focus of most empirical field-based studies with comparatively less focus on semi-alluvial bedrock channels located in other regions. In this study, we present an inventory of channel geometry data collected from semi-alluvial bedrock channels in Ontario and Québec, Canada, which are not subject to tectonic uplift. Data were sourced from a variety of physiographic settings, permitting evaluation of the influence of alluvial cover, lithology, and gradient on cross-sectional channel form. Our results show no substantial difference in channel width or scaling behaviour amongst bedrock, mixed, and alluvial channels included in our study, except for sedimentary bedrock channels virtually bare of alluvial cover that represent a uniquely wide, distinct subgroup. Channel gradient does not appear to exhibit any observable control on channel width amongst our study rivers, suggesting that sedimentary bedrock channels form a distinct subgroup because of lithology. Comparatively, the widths of our bedrock channels formed in igneous/metamorphic bedrock are comparable to the widths of mixed channels and alluvial channels for a given discharge and drainage area. Our findings also suggest that cross-sectional adjustment of sedimentary bedrock channels is achieved through lateral erosion of the channel banks and downward erosion of the channel bed, whereas cross-sectional adjustment of igneous/metamorphic bedrock is primarily achieved through downward erosion of the bed with limited lateral erosion of the banks.
Assessing vulnerability in stream channel evolution in relation with morphological transformations and hydrodynamic behavior. Case Study: the Subcarpathian Prahova Valley, Romania

NASA Astrophysics Data System (ADS)

Osaci-Costache, G.; Armas, I.; Gogoase Nistoran, D.; Gheorghe, D.

2010-05-01

The objective of the study is to analyze the relationship between morphological transformations observed during the last 200 years along a 20 km reach of Prahova river, and hydrodynamic behavior during high intensity flood periods, in the context of erosion-control works and environmental changes. Along this sub-Carpathian reach, Prahova is a typical mountain river, partially regulated, flowing under fluvial and torrential regime and having a mean thalweg slope of about 1%. Riverbed material consists in cobbles and boulders. Its valley has gradually been cut; therefore four terraces may clearly be identified in the subbasin areas of Breaza and Câmpina. The Holocene floodplain is asymmetrical, and during the last decades an incision of about 3-4 m has clearly been observed in the main channel. This also led to an evolution from an anabranching river aspect to a meandering one along the studied reach. Reasons to explain these changes are a positive neotectonic background coupled with an increased anthropic component (granular material extraction, channel regulation for construction purposes of roads, bridges, railways, layout of gas and oil pipelines, vegetation cutoff etc.). The data obtained from 1900-1980 topographical maps and 1997-2002 satellite images and orthophotos were coupled with topo-bathymetric surveys carried out in 57 cross-sections, in order to obtain the DTM of the studied area. These cross-sections were used to build up the geometry of a 1D hydraulic model by using the HEC-RAS software (USACE, version 3.1.3). Simulations were obtained under steady flow conditions for 1% and 2% return periods (360-400 mc/s and 450-500 mc/s). Calibration of Manning roughness factors was performed on stages measured at the two upstream and downstream gauging stations. High values of computed shear stresses and velocities show areas of potential erosion leading to morphological changes, bank collapsing and incision observed during the last decades and predicted for the near future. Three main areas of erosion were identified, where the river has cut real gorges, up to over 4m depths. These findings where correlated with geological, morphological and land use data in a complex vulnerability approach, incorporated in a Geographical Information System. The results obtained could be very useful for local authorities when developing risk mitigation programs.
Uncertainties in selected river water quality data

NASA Astrophysics Data System (ADS)

Rode, M.; Suhr, U.

2007-02-01

Monitoring of surface waters is primarily done to detect the status and trends in water quality and to identify whether observed trends arise from natural or anthropogenic causes. Empirical quality of river water quality data is rarely certain and knowledge of their uncertainties is essential to assess the reliability of water quality models and their predictions. The objective of this paper is to assess the uncertainties in selected river water quality data, i.e. suspended sediment, nitrogen fraction, phosphorus fraction, heavy metals and biological compounds. The methodology used to structure the uncertainty is based on the empirical quality of data and the sources of uncertainty in data (van Loon et al., 2005). A literature review was carried out including additional experimental data of the Elbe river. All data of compounds associated with suspended particulate matter have considerable higher sampling uncertainties than soluble concentrations. This is due to high variability within the cross section of a given river. This variability is positively correlated with total suspended particulate matter concentrations. Sampling location has also considerable effect on the representativeness of a water sample. These sampling uncertainties are highly site specific. The estimation of uncertainty in sampling can only be achieved by taking at least a proportion of samples in duplicates. Compared to sampling uncertainties, measurement and analytical uncertainties are much lower. Instrument quality can be stated well suited for field and laboratory situations for all considered constituents. Analytical errors can contribute considerably to the overall uncertainty of river water quality data. Temporal autocorrelation of river water quality data is present but literature on general behaviour of water quality compounds is rare. For meso scale river catchments (500-3000 km2) reasonable yearly dissolved load calculations can be achieved using biweekly sample frequencies. For suspended sediments none of the methods investigated produced very reliable load estimates when weekly concentrations data were used. Uncertainties associated with loads estimates based on infrequent samples will decrease with increasing size of rivers.
Evaluating Connectivity for two mid-sized mammals Across Riparian Corridors using Wildlife Crossing Monitoring and Species Distribution Modeling

NASA Astrophysics Data System (ADS)

Jeong, S.

2016-12-01

The movement of wildlife can be constrained by river renovation projects owing to the presence of artificial structures. This study evaluates lateral connectivity, the ability to cross from habitat on one side of the river, through riparian vegetation, embankments, and the river to the other, of two mammal species, the leopard cat (Felis bengalensis euptilura) and water deer (Hydropotes inermis). We used 34 months of monitoring on 250 m stream segments on the Seom river, in South Korea to model the lateral connectivity of the stream between suitable habitats on either side of the steam. Habitat suitability within the landscape was determined using species distribution modelingand was used to determine where we thought the animals would want to pass across the river. We compared the predicted crossing locations to observed crossings.We assessed lateral connectivity suitability with maximum entropy and logistic regression models, and species' presences detected from snow tracking, heat sensor cameras, and scat or other signs, as well as landscape variables. Leopard cats prefer upland forest, while water deer prefer the forest edge and riparian corridor. For both target species, the best riparian habitats were characterized by the presence of vegetation cover on the embankment and by at least one side of an embankment being adjacent to farmland or forest cover. The lateral connectivity for the two target species showed different requirements. Water deer cross through large culverts with an openness ratio of 0.7 or under bridges, whereas leopard cats utilized drainage pipes and culvert boxes with a much smaller openness ratio. Stream reaches located close to a river tributary had the highest connectivity values, and areas modeled as good habitat for both species thatlink watershed and riparian habitats showed high connectivity values. Artifacts such as steep banks, concrete embankments, and adjacent roads were found to degrade the lateral connectivity of wildlife. These outcomes can be used to identify suitable riparian wildlife habitats of mammals, to evaluate lateral connectivity of riparian corridors for mammals, and to develop criteria for river conservation and restoration in highly urbanized developing countries. [
Sports Participation and Social Personality Variable of Students in Secondary Schools in Central Senatorial District of Cross River State, Nigeria

ERIC Educational Resources Information Center

Edim, M. E.; Odok, E. A.

2015-01-01

The main thrust of this study was to investigate sports participation and social personality variable of students in secondary schools in Central Senatorial District of Cross River State, Nigeria. To achieve the purpose of this study, one hypothesis was formulated to guide the study. Literature review was carried out according to the variable of…
Instructional Supervisory Practices and Teachers' Role Effectiveness in Public Secondary Schools in Calabar South Local Government Area of Cross River State, Nigeria

ERIC Educational Resources Information Center

Sule, Mary Anike; Eyiene, Ameh; Egbai, Mercy E.

2015-01-01

The study investigated the relationship between instructional supervisory practices and teachers' role effectiveness in public secondary schools in Calabar South Local Government Area of Cross River State. Two null hypotheses were formulated to guide the study. Ex-post facto research design was adopted for the study. The population of the study…
Comparative Analysis of Selected Motor Fitness Profile of Football Referees in Cross River and AKWA IBOM States, Nigeria

ERIC Educational Resources Information Center

Ogabor, J. O.; Sanusi, M.; Saulawa, A. I.

2015-01-01

The purpose of this study was to compare selected motor fitness profile of football referees in Cross River and Akwa Ibom States. Motor fitness profiles compared were running speed and agility of the referees. Standardized equipment and procedures were employed in the tests. To achieve the objectives of the study, two research hypotheses were…
The Tools, Approaches and Applications of Visual Literacy in the Visual Arts Department of Cross River University of Technology, Calabar, Nigeria

ERIC Educational Resources Information Center

Ecoma, Victor

2016-01-01

The paper reflects upon the tools, approaches and applications of visual literacy in the Visual Arts Department of Cross River University of Technology, Calabar, Nigeria. The objective of the discourse is to examine how the visual arts training and practice equip students with skills in visual literacy through methods of production, materials and…
Promoting Peace Education for Behaviourial Changes in Public Secondary Schools in Calabar Municipality Council Area, Cross River State, Nigeria

ERIC Educational Resources Information Center

Uko, E. S.; Igbineweka, P. O.; Odigwe, F. N.

2015-01-01

This study aimed at investigating the promotion of peace education for behavioural changes in public secondary schools in Calabar Municipal Council Area of Cross River State. A descriptive survey design was adopted for the study. A set of questionnaire items were validated and used for the collection of data involving 310 respondents, selected…
Bridging Policy Implementation Gaps in Nigerian Education System: A Case Study of Universal Basic Education Programme in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ogbiji, Joseph Etiongbie; Ogbiji, Sylvanus Achua

2016-01-01

This research focuses on identifying policy gaps in the implementation of Universal Basic Education (UBE) programme in Nigeria, with Cross River State being the study area. The three research questions used for the research center on the extent of the freeness of the UBE, the extent to which the programme has stimulated educational consciousness…
Risk factors for schistosomiasis transmission among school children in Gwanda district, Zimbabwe.

PubMed

Nyati-Jokomo, Zibusiso; Chimbari, Moses J

2017-11-01

A nationwide cross sectional schistosomiasis survey conducted in 2011 in 280 primary schools found a prevalence rate of 22.7%. This warranted an intervention with Mass Drug Administration at all schools in line with WHO guidelines. This study aimed to identify risk factors for schistosomiasis transmission among Grade 3 children at two primary schools in Gwanda district. A descriptive cross sectional survey which was part of a larger study on Malaria and Bilharzia in Southern Africa (MABISA) was conducted. Grade 3 children (n=120) attending two purposively selected rural primary schools in Dombo and Ntalale in Gwanda were respondents. Data on socio-demographic characteristics and risk factors which included knowledge and practices were collected using a pretested interviewer administered questionnaire. Of the 120 children, 98 (81.7%) of the children indicated that they did not consistently use the toilet. The other risk factors for schistosomiasis were bathing and swimming in rivers and dams 80 (66.7%), watering the vegetable gardens using unprotected water sources 77 (64.7%) and crossing rivers on their way to school barefooted 31.7%. History of schistosomiasis cases based on self-reporting indicated that of the 9 children 7 were girls. There was poor knowledge of schistosomiasis among the children with 54% of the children indicating that they had never heard about the disease. Misconceptions on the causes of schistosomiasis which included drinking dirty water, mosquitoes and flies as the causes of schistosomiasis were reported by the children. Parents were cited as the least disseminators of information on schistosomiasis with only 4 out of the 120 children having received information from their parents. Frequent contact with unprotected water sources, non-use of the toilet, and lack of information on schistosomiasis could predispose the children to infection. There is need to raise awareness about schistosomiasis in schools and the community to reduce the risk of contracting schistosomiasis due to risky behaviour. Copyright © 2017. Published by Elsevier B.V.
Assessing the Importance of Cross-Stream Transport in Bedload Flux Estimates from Migrating Dunes: Colorado River, Grand Canyon National Park

NASA Astrophysics Data System (ADS)

Leary, K. P.; Buscombe, D.; Schmeeckle, M.; Kaplinski, M. A.

2017-12-01

Bedforms are ubiquitous in sand-bedded rivers, and understanding their morphodynamics is key to quantifying bedload transport. As such, mechanistic understanding of the spatiotemporal details of sand transport through and over bedforms is paramount to quantifying total sediment flux in sand-bedded river systems. However, due to the complexity of bedform field geometries and migration in natural settings, our ability to relate migration to bedload flux, and to quantify the relative role of tractive and suspended processes in their dynamics, is incomplete. Recent flume and numerical investigations indicate the potential importance of cross-stream transport, a process previously regarded as secondary and diffusive, to the three-dimensionality of bedforms and spatially variable translation and deformation rates. This research seeks to understand and quantify the importance of cross-stream transport in bedform three-dimensionality in a field setting. This work utilizes a high-resolution (0.25 m grid) data set of bedforms migrating in the channel of the Colorado River in Grand Canyon National Park. This data set comprises multi-beam sonar surveys collected at 3 different flow discharges ( 283, 566, and 1076 m3/s) along a reach of the Colorado River just upstream of the Diamond Creek USGS gage. Data were collected every 6 minutes almost continuously for 12 hours. Using bed elevation profiles (BEPs), we extract detailed bedform geometrical data (i.e. bedform height, wavelength) and spatial sediment flux data over a suite of bedforms at each flow. Coupling this spatially extensive data with a generalized Exner equation, we conduct mass balance calculations that evaluate the possibility, and potential importance, of cross-stream transport in the spatial variability of translation and deformation rates. Preliminary results suggest that intra-dune cross-stream transport can partially account for changes in the planform shape of dunes and may play an important role in spatially variable translation and deformation rates. Parameterization of cross-stream sediment transport could lead to accounting for ambiguities in bedload flux calculations caused by dune deformation, which in turn could significantly improve overall calculation of bedload and total load sediment transport in sand bedded rivers.
44. SECTIONS OF POWER HOUSE, EXHIBIT L, SANTA ANA RIVER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

44. SECTIONS OF POWER HOUSE, EXHIBIT L, SANTA ANA RIVER NO. 2 PROJECT, APR. 30, 1945. SCE drawing no. 523644 (sheet no. 15; for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, SAR-2 Powerhouse, Redlands, San Bernardino County, CA
Assessment Approach for Identifying Compatibility of Restoration Projects with Geomorphic and Flooding Processes in Gravel Bed Rivers

NASA Astrophysics Data System (ADS)

DeVries, Paul; Aldrich, Robert

2015-08-01

A critical requirement for a successful river restoration project in a dynamic gravel bed river is that it be compatible with natural hydraulic and sediment transport processes operating at the reach scale. The potential for failure is greater at locations where the influence of natural processes is inconsistent with intended project function and performance. We present an approach using practical GIS, hydrologic, hydraulic, and sediment transport analyses to identify locations where specific restoration project types have the greatest likelihood of working as intended because their function and design are matched with flooding and morphologic processes. The key premise is to identify whether a specific river analysis segment (length ~1-10 bankfull widths) within a longer reach is geomorphically active or inactive in the context of vertical and lateral stabilities, and hydrologically active for floodplain connectivity. Analyses involve empirical channel geometry relations, aerial photographic time series, LiDAR data, HEC-RAS hydraulic modeling, and a time-integrated sediment transport budget to evaluate trapping efficiency within each segment. The analysis segments are defined by HEC-RAS model cross sections. The results have been used effectively to identify feasible projects in a variety of alluvial gravel bed river reaches with lengths between 11 and 80 km and 2-year flood magnitudes between ~350 and 1330 m3/s. Projects constructed based on the results have all performed as planned. In addition, the results provide key criteria for formulating erosion and flood management plans.
Assessment Approach for Identifying Compatibility of Restoration Projects with Geomorphic and Flooding Processes in Gravel Bed Rivers.

PubMed

DeVries, Paul; Aldrich, Robert

2015-08-01

A critical requirement for a successful river restoration project in a dynamic gravel bed river is that it be compatible with natural hydraulic and sediment transport processes operating at the reach scale. The potential for failure is greater at locations where the influence of natural processes is inconsistent with intended project function and performance. We present an approach using practical GIS, hydrologic, hydraulic, and sediment transport analyses to identify locations where specific restoration project types have the greatest likelihood of working as intended because their function and design are matched with flooding and morphologic processes. The key premise is to identify whether a specific river analysis segment (length ~1-10 bankfull widths) within a longer reach is geomorphically active or inactive in the context of vertical and lateral stabilities, and hydrologically active for floodplain connectivity. Analyses involve empirical channel geometry relations, aerial photographic time series, LiDAR data, HEC-RAS hydraulic modeling, and a time-integrated sediment transport budget to evaluate trapping efficiency within each segment. The analysis segments are defined by HEC-RAS model cross sections. The results have been used effectively to identify feasible projects in a variety of alluvial gravel bed river reaches with lengths between 11 and 80 km and 2-year flood magnitudes between ~350 and 1330 m(3)/s. Projects constructed based on the results have all performed as planned. In addition, the results provide key criteria for formulating erosion and flood management plans.
Discharge-measurement system using an acoustic Doppler current profiler with applications to large rivers and estuaries

USGS Publications Warehouse

Simpson, Michael R.; Oltmann, Richard N.

1993-01-01

Discharge measurement of large rivers and estuaries is difficult, time consuming, and sometimes dangerous. Frequently, discharge measurements cannot be made in tide-affected rivers and estuaries using conventional discharge-measurement techniques because of dynamic discharge conditions. The acoustic Doppler discharge-measurement system (ADDMS) was developed by the U.S. Geological Survey using a vessel-mounted acoustic Doppler current profiler coupled with specialized computer software to measure horizontal water velocity at 1-meter vertical intervals in the water column. The system computes discharge from water-and vessel-velocity data supplied by the ADDMS using vector-algebra algorithms included in the discharge-measurement software. With this system, a discharge measurement can be obtained by engaging the computer software and traversing a river or estuary from bank to bank; discharge in parts of the river or estuarine cross sections that cannot be measured because of ADDMS depth limitations are estimated by the system. Comparisons of ADDMS-measured discharges with ultrasonic-velocity-meter-measured discharges, along with error-analysis data, have confirmed that discharges provided by the ADDMS are at least as accurate as those produced using conventional methods. In addition, the advantage of a much shorter measurement time (2 minutes using the ADDMS compared with 1 hour or longer using conventional methods) has enabled use of the ADDMS for several applications where conventional discharge methods could not have been used with the required accuracy because of dynamic discharge conditions.

33 CFR 165.510 - Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area. 165.510 Section 165.510... Limited Access Areas Fifth Coast Guard District § 165.510 Delaware Bay and River, Salem River, Christina...
33 CFR 165.510 - Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Delaware Bay and River, Salem River, Christina River and Schuylkill River-Regulated Navigation Area. 165.510 Section 165.510... Limited Access Areas Fifth Coast Guard District § 165.510 Delaware Bay and River, Salem River, Christina...
Description of chronostratigraphic units preserved as channel deposits and geomorphic processes following a basin-scale disturbance by a wildfire in Colorado

USGS Publications Warehouse

Moody, John A.; Martin, Deborah A.

2017-10-11

The consequence of a 1996 wildfire disturbance and a subsequent high-intensity summer convective rain storm (about 110 millimeters per hour) was the deposition of a sediment superslug in the Spring Creek basin (26.8 square kilometers) of the Front Range Mountains in Colorado. Spring Creek is a tributary to the South Platte River upstream from Strontia Springs Reservoir, which supplies domestic water for the cities of Denver and Aurora. Changes in a superslug were monitored over the course of 18 years (1996–2014) by repeat surveys at 18 channel cross sections spaced at nearly equal intervals along a 1,500-meter study reach and by a time series of photographs of each cross section. Surveys were not repeated at regular time intervals but after major changes caused by different geomorphic processes. The focus of this long-term study was to understand the evolution and internal alluvial architecture of chronostratigraphic units (defined as the volume of sediment deposited between two successive surveys), and the preservation or storage of these units in the superslug. The data are presented as a series of 18 narratives (one for each cross section) that summarize the changes, illustrate these changes with photographs, and provide a preservation plot showing the amount of each chronostratigraphic unit still remaining in June 2014.The most significant hydrologic change after the wildfire was an exponential decrease in peak discharge of flash floods caused by summer convective rain storms. In response to these hydrologic changes, all 18 locations went through an aggradation phase, an incision phase, and finally a stabilization phase. However, the architecture of the chronostratigraphic units differs from cross section to cross section, and units are characterized by either a laminar, fragmented, or hybrid alluvial architecture. In response to the decrease in peak-flood discharge and the increase in hillslope and riparian vegetation, Spring Creek abandoned many of the nearly horizontal erosional and depositional surfaces and left a landscape consisting of a series of cut-and-fill terraces as a legacy of this wildfire disturbance.
Large scale reactive transport of nitrate across the surface water divide

NASA Astrophysics Data System (ADS)

Kortunov, E.; Lu, C.; Amos, R.; Grathwohl, P.

2016-12-01

Groundwater pollution caused by agricultural and atmospheric inputs is a pressing issue in environmental management worldwide. Various researchers have studied different aspects of nitrate contamination since the substantial increase of the agriculture pollution in the second half of the 20th century. This study addresses large scale reactive solute transport in a typical Germany hilly landscapes in a transect crossing 2 valleys: River Neckar and Ammer. The numerical model was constructed compromising a 2-D cross-section accounting for typical fractured mudstones and unconsolidated sediments. Flow modelling showed that the groundwater divide significantly deviates from the surface water divide providing conditions for inter-valley flow and transport. Reactive transport modelling of redox-sensitive solutes (e.g. agriculture nitrate and natural sulfate, DOC, ammonium) with MIN3P was used to elucidate source of nitrate in aquifers and rivers. Since both floodplains, in the Ammer and Neckar valley contain Holocene sediments relatively high in organic carbon, agricultural nitrate is reduced therein and does not reach the groundwater. However, nitrate applied in the hillslopes underlain by fractured oxidized mudrock is transported to the high yield sand and gravel aquifer in the Neckar valley. Therefore, the model predicts that nitrate in the Neckar valley comes, to a large extent, from the neighboring Ammer valley. Moreover, nitrate observed in the rivers and drains in the Ammer valley is very likely geogenic since frequent peat layers there release ammonium which is oxidized as it enters the surface water. Such findings are relevant for land and water quality management.
27 CFR 9.210 - Lehigh Valley.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Lehigh River in the city of Jim Thorpe; then (8) Proceed east-northeasterly in a straight line to the... along Interstate 80 through Stroudsburg to the west bank of the Delaware River; then (15) Proceed south (downstream) along the west bank of the Delaware River, and, crossing onto the Northampton County map...
9. VIEW FROM MANY PARKS CURVE (ON TRAIL RIDGE ROAD) ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. VIEW FROM MANY PARKS CURVE (ON TRAIL RIDGE ROAD) OF HORSESHOE PARK, SHOWING FALL RIVER ROAD FAINTLY AT LEFT AT BASE OF SHEEP MOUNTAIN AND CROSSING ALLUVIAL FAN FROM LAWN LAKE FLOOD. - Fall River Road, Between Estes Park & Fall River Pass, Estes Park, Larimer County, CO
The genera Isorineloricaria and Aphanotorulus (Siluriformes: Loricariidae)
with description of a new species.

PubMed

Ray, C Keith; Armbruster, Jonathan W

2016-02-04

We review the complex history of those species included in the Hypostomus emarginatus species complex and recognize them in Isorineloricaria and Aphanotorulus. Isorineloricaria consists of four valid species: I. acuarius n. sp., I. spinosissima, I. tenuicauda, and I. villarsi. Aphanotorulus consists of six valid species: A. ammophilus, A, emarginatus, A. gomesi, A. horridus, A. phrixosoma, and A. unicolor. Plecostomus annae and Hypostoma squalinum are placed in the synonymy of A. emarginatus; Plecostomus biseriatus, P. scopularius, and P. virescens are placed in the synonymy of A. horridus; Plecostomus winzi is placed in the synonymy of I. tenuicauda, and one new species, I. acuarius is described from the Apure River basin of Venezuela. Aphanotoroulus can be distinguished from Isorineloricaria by having caudal peduncles that do not become greatly lengthed with size and that are oval in cross section (vs. caudal peduncle proportions that get proportionately longer with size and that become round in cross-section), and by having small dark spots (less than half plate diameter) on a light tan background (vs. spots almost as large as lateral plates on a nearly white background.
Level II scour analysis for Bridge 12 (CHESVT01030012) on State Highway 103, crossing the Williams River, Chester, Vermont

USGS Publications Warehouse

Flynn, Robert H.; Burns, Ronda L.

1997-01-01

northerly pier) and from 13.5 to 17.1 ft along Pier 2 (southerly pier). The worst case pier scour occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured -streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1995, p. 47). Usually, computed scour depths are evaluated in combination with other information including (but not limited to) historical performance during flood events, the geomorphic stability assessment, existing scour protection measures, and the results of the hydraulic analyses. Therefore, scour depths adopted by VTAOT may differ from the computed values documented herein.
11. Photocopy of photograph (original copy in Edison collection). Photographer ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Photocopy of photograph (original copy in Edison collection). Photographer and date unknown, although photo taken prior to 1930 reconstruction of Project flumes. VIEW OF ORIGINAL SOUTH FORK OF THE TULE RIVER MIDDLE FORK "BOX" WOOD FLUME BRANCH SHOWING NORTH FORK OF TULE RIVER MIDDLE FORK CROSSING. VIEW TO NORTHWEST. - Tule River Hydroelectric Project, Water Conveyance System, Middle Fork Tule River, Springville, Tulare County, CA
Sediment transport and deposition on a river-dominated tidal flat: An idealized model study

USGS Publications Warehouse

Sherwood, Christopher R.; Chen, Shih-Nan; Geyer, W. Rockwell; Ralston, David K.

2010-01-01

A 3-D hydrodynamic model is used to investigate how different size classes of river-derived sediment are transported, exported and trapped on an idealized, river-dominated tidal flat. The model is composed of a river channel flanked by sloping tidal flats, a configuration motivated by the intertidal region of the Skagit River mouth in Washington State, United States. It is forced by mixed tides and a pulse of freshwater and sediment with various settling velocities. In this system, the river not only influences stratification but also contributes a significant cross-shore transport. As a result, the bottom stress is strongly ebb-dominated in the channel because of the seaward advance of strong river flow as the tidal flats drain during ebbs. Sediment deposition patterns and mass budgets are sensitive to settling velocity. The lateral sediment spreading scales with an advective distance (settling time multiplied by lateral flow speed), thereby confining the fast settling sediment classes in the channel. Residual sediment transport is landward on the flats, because of settling lag, but is strongly seaward in the channel. The seaward transport mainly occurs during big ebbs and is controlled by a length scale ratio Ld/XWL, where Ld is a cross-shore advective distance (settling time multiplied by river outlet velocity), and XWL is the immersed cross-shore length of the intertidal zone. Sediment trapping requires Ld/XWL < 1, leading to more trapping for the faster settling classes. Sensitivity studies show that including stratification and reducing tidal range both favor sediment trapping, whereas varying channel geometries and asymmetry of tides has relatively small impacts. Implications of the modeling results on the south Skagit intertidal region are discussed.
50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

Code of Federal Regulations, 2012 CFR

2012-10-01

... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

Code of Federal Regulations, 2013 CFR

2013-10-01

... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

Code of Federal Regulations, 2014 CFR

2014-10-01

... salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook... River salmon (except reaches above impassable natural falls, and Dworshak and Hells Canyon Dams...
[Study on distribution and countermeasures of Oncomelania snails in beach wetlands of Runzhou section of lower reaches of Yangtze River].

PubMed

Xia, Ai; Huang, Yixin; Jiang, Jun; Zhou, Ya-Min; Hang, De-rong; Tao, Heng-ye

2014-04-01

To understand the distribution of the river beach wetlands and Oncomelania snails in the lower reaches of the Yangtze River, and explore the countermeasures of snail control. The river beach wetlands outside the Yangtze River levee were investigated and classified according to the hierarchical and classification system of wetlands of China. The snail survey was carried out in the beach wetlands of Runzhou section of lower reaches of the Yangtze River from 2004 to 2013. The change trend of snail areas and the densities was analyzed in the wetlands. The river beach of Runzhou section of lower reaches of the Yangtze River belongs to the riverine wetland. There was Oncomelania snail breeding except the permanent water area. At present, there were natural wetlands of 1303.0 hm2, human-made wetlands of 1479.0 hmb2 and wetland function changes of 1059.0 hm2 in the river beach of Runzhou section. There was the snail area of 181.4 hm2 in the natural wetland in 2013. The area of snail control by the molluscicide and environmental modification was 4624.55 hm2 from 2004 to 2013. The decline rates of snail areas and densities were 66.53% and 77.66% respectively. The existing Oncomelania snails were distributed in the natural wetlands. The human-made wetland is helpful to snail control. The snail control in the river beach wetlands should attach a great importance to the protection of wetland ecology.
Airborne laser topographic mapping results from initial joint NASA/US Army Corps of Engineers experiment

NASA Technical Reports Server (NTRS)

Krabill, W. B.; Collins, J. G.; Swift, R. N.; Butler, M. L.

1980-01-01

Initial results from a series of joint NASA/US Army Corps of Engineers experiments are presented. The NASA Airborne Oceanographic Lidar (AOL) was exercised over various terrain conditions, collecting both profile and scan data from which river basin cross sections are extracted. Comparisons of the laser data with both photogrammetry and ground surveys are made, with 12 to 27 cm agreement observed over open ground. Foliage penetration tests, utilizing the unique time-waveform sampling capability of the AOL, indicate 50 cm agreement with photogrammetry (known to have difficulty in foliage covered terrain).
Reactivity impact of {sup 16}O thermal elastic-scattering nuclear data for some numerical and critical benchmark systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozier, K. S.; Roubtsov, D.; Plompen, A. J. M.

2012-07-01

The thermal neutron-elastic-scattering cross-section data for {sup 16}O used in various modern evaluated-nuclear-data libraries were reviewed and found to be generally too high compared with the best available experimental measurements. Some of the proposed revisions to the ENDF/B-VII.0 {sup 16}O data library and recent results from the TENDL system increase this discrepancy further. The reactivity impact of revising the {sup 16}O data downward to be consistent with the best measurements was tested using the JENDL-3.3 {sup 16}O cross-section values and was found to be very small in MCNP5 simulations of the UO{sub 2} and reactor-recycle MOX-fuel cases of the ANSmore » Doppler-defect numerical benchmark. However, large reactivity differences of up to about 14 mk (1400 pcm) were observed using {sup 16}O data files from several evaluated-nuclear-data libraries in MCNP5 simulations of the Los Alamos National Laboratory HEU heavy-water solution thermal critical experiments, which were performed in the 1950's. The latter result suggests that new measurements using HEU in a heavy-water-moderated critical facility, such as the ZED-2 zero-power reactor at the Chalk River Laboratories, might help to resolve the discrepancy between the {sup 16}O thermal elastic-scattering cross-section values and thereby reduce or better define its uncertainty, although additional assessment work would be needed to confirm this. (authors)« less
The late early Miocene Sabine River

DOE Office of Scientific and Technical Information (OSTI.GOV)

Manning, E.

Work on a new late early Miocene vertebrate fossil site, in a paleochannel deposit of the upper Carnahan Bayou Member of the lower Fleming Formation, has revealed unexpected data on the course and nature of the Sabine River of that time. Screen washing for smaller vertebrate remains at the site, just west of the Sabine River in Newton County, central eastern Texas, has resulted in the recovery of early Permian, Early Cretaceous, Late Cretaceous (Maestrichtian), Paleocene/Eocene, late Eocene, and Oligocene/Miocene fossils, in addition to the main early Miocene fauna. The reworked fossils, as well as distinctive mineral grains, show thatmore » the late early Miocene Sabine River was connected to the Texas/Oklahoma/Arkansas boundary section of the Red River, as well as to rivers draining the southern Ouachita Mountains. These rivers must have joined the Texas/Louisiana boundary section of the Sabine River somewhere in northwest Louisiana at that time. This suggests that the Louisiana section of the present Red River pirated the Texas/Oklahoma/Arkansas boundary section of the river some time after the early Miocene. The preservation of recognizable fossils transported hundreds of miles in a large river itself requires explanation. It is speculated here that the late early Miocene Sabine River incorporated a large amount of the then recently deposited volcanic ash from the Trans-Pecos Volcanic Field. Montmorillonite clay from the altered volcanic ash would have made the river very turbid, which could have allowed coarse sand-sized particles to be carried in the suspended load of the river, rather than in its bed load (where they would have been destroyed by the rolling chert gravel). Additional evidence for such long-distance fossil transport in the late early Miocene rivers of the western Gulf Coastal Plain comes from the abundant Cretaceous fossils of the upper Oakville Formation of southeast Texas and the Siphonina davisi zone of the southeast Texas subsurface.« less
38. From hilltop, Route 14, last segment of flume before ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

38. From hilltop, Route 14, last segment of flume before Broughton Lumber Company. Section of flume and broken out section. Columbia River and Oregon in background. West/southwest 240 degrees. - Broughton Flume, Hood River Junction on Columbia River at Washington/Oregon border, Hood, Skamania County, WA
Utilization of Information and Communication Technology (ICT) Resources and Job Effectiveness among Library Staff in the University of Calabar and Cross River University of Technology, Nigeria

ERIC Educational Resources Information Center

Ntui, Aniebiet Inyang; Inyang, Comfort Linus

2015-01-01

This study investigated utilization of Information and Communication Technology (ICT) resources and job effectiveness among library staff in the University of Calabar and Cross River University of Technology, Nigeria. To achieve the purpose of this study, four hypotheses were formulated to guide the study. Ex-post facto research design was adopted…
Floods in Starkweather Creek basin, Madison, Wisconsin

USGS Publications Warehouse

Lawrence, Carl L.; Holmstrom, Barry K.

1972-01-01

The reaches evaluated are (1) Starkweather Creek and West Branch Starkweather Creek, for a distance of 6.0 river miles from the mouth at Lake Monona upstream to the U.S. Highway 51 crossing north of Truax Field; and (2) East Branch Starkweather Creek (2.8 river miles), from its confluence with the West Branch near Milwaukee Street upstream to a point near the Interstate Highway 90-94 crossing.

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