Methodology and Implications of Maximum Paleodischarge Estimates for

USGS Publications Warehouse

Channels, M.; Pruess, J.; Wohl, E.E.; Jarrett, R.D.

1998-01-01

Historical and geologic records may be used to enhance magnitude estimates for extreme floods along mountain channels, as demonstrated in this study from the San Juan Mountains of Colorado. Historical photographs and local newspaper accounts from the October 1911 flood indicate the likely extent of flooding and damage. A checklist designed to organize and numerically score evidence of flooding was used in 15 field reconnaissance surveys in the upper Animas River valley of southwestern Colorado. Step-backwater flow modeling estimated the discharges necessary to create longitudinal flood bars observed at 6 additional field sites. According to these analyses, maximum unit discharge peaks at approximately 1.3 m3 s~' km"2 around 2200 m elevation, with decreased unit discharges at both higher and lower elevations. These results (1) are consistent with Jarrett's (1987, 1990, 1993) maximum 2300-m elevation limit for flash-flooding in the Colorado Rocky Mountains, and (2) suggest that current Probable Maximum Flood (PMF) estimates based on a 24-h rainfall of 30 cm at elevations above 2700 m are unrealistically large. The methodology used for this study should be readily applicable to other mountain regions where systematic streamflow records are of short duration or nonexistent. ?? 1998 Regents of the University of Colorado.

77 FR 74142 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-13

...-2011-0002; Internal Agency Docket No. FEMA-B-1100 and FEMA-B-1222] Proposed Flood Elevation... Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs for communities participating in the National Flood Insurance Program (NFIP), in accordance with section 110 of the Flood Disaster Protection...

Analysis of water-surface profiles in Leon County and the city of Tallahassee, Florida

USGS Publications Warehouse

Franklin, M.A.; Orr, R.A.

1987-01-01

Water surface profiles for the 10-, 25-, 50-, and 100-yr recurrence interval floods for most of the streams that drain developing areas of Leon County and the city of Tallahassee are presented. The principal streams studied are in the Lake Munson, Lake Lafayette, and Lake Jackson basins Peak discharges were computed from regression equations based on information gained from 15 streamflow stations in the area. Standard step-backwater procedures were used to determine the water-surface elevations for the streams. The flood elevations were generally higher than those in the Flood Insurance Studies for Tallahassee (1976) and Leon County (1982). The primary reason for the higher profiles is that peak discharges used in this report are larger than those used previously, largely due to changes in land use. The flood profiles for Bradford Brook, North Branch Gum Creek, and West Branch Gum Creek generally match those in the Leon County Flood Insurance Studies. Channel improvements in some areas would lower the flood elevation in that area, but would probably increase flooding downstream. (Lantz-PTT)

Development of regional skews for selected flood durations for the Central Valley Region, California, based on data through water year 2008

USGS Publications Warehouse

Lamontagne, Jonathan R.; Stedinger, Jery R.; Berenbrock, Charles; Veilleux, Andrea G.; Ferris, Justin C.; Knifong, Donna L.

2012-01-01

Flood-frequency information is important in the Central Valley region of California because of the high risk of catastrophic flooding. Most traditional flood-frequency studies focus on peak flows, but for the assessment of the adequacy of reservoirs, levees, other flood control structures, sustained flood flow (flood duration) frequency data are needed. This study focuses on rainfall or rain-on-snow floods, rather than the annual maximum, because rain events produce the largest floods in the region. A key to estimating flood-duration frequency is determining the regional skew for such data. Of the 50 sites used in this study to determine regional skew, 28 sites were considered to have little to no significant regulated flows, and for the 22 sites considered significantly regulated, unregulated daily flow data were synthesized by using reservoir storage changes and diversion records. The unregulated, annual maximum rainfall flood flows for selected durations (1-day, 3-day, 7-day, 15-day, and 30-day) for all 50 sites were furnished by the U.S. Army Corps of Engineers. Station skew was determined by using the expected moments algorithm program for fitting the Pearson Type 3 flood-frequency distribution to the logarithms of annual flood-duration data. Bayesian generalized least squares regression procedures used in earlier studies were modified to address problems caused by large cross correlations among concurrent rainfall floods in California and to address the extensive censoring of low outliers at some sites, by using the new expected moments algorithm for fitting the LP3 distribution to rainfall flood-duration data. To properly account for these problems and to develop suitable regional-skew regression models and regression diagnostics, a combination of ordinary least squares, weighted least squares, and Bayesian generalized least squares regressions were adopted. This new methodology determined that a nonlinear model relating regional skew to mean basin elevation was the best model for each flood duration. The regional-skew values ranged from -0.74 for a flood duration of 1-day and a mean basin elevation less than 2,500 feet to values near 0 for a flood duration of 7-days and a mean basin elevation greater than 4,500 feet. This relation between skew and elevation reflects the interaction of snow and rain, which increases with increased elevation. The regional skews are more accurate, and the mean squared errors are less than in the Interagency Advisory Committee on Water Data's National skew map of Bulletin 17B.

Estimated Flood-Inundation Mapping for the Upper Blue River, Indian Creek, and Dyke Branch in Kansas City, Missouri, 2006-08

USGS Publications Warehouse

Kelly, Brian P.; Huizinga, Richard J.

2008-01-01

In the interest of improved public safety during flooding, the U.S. Geological Survey, in cooperation with the city of Kansas City, Missouri, completed a flood-inundation study of the Blue River in Kansas City, Missouri, from the U.S. Geological Survey streamflow gage at Kenneth Road to 63rd Street, of Indian Creek from the Kansas-Missouri border to its mouth, and of Dyke Branch from the Kansas-Missouri border to its mouth, to determine the estimated extent of flood inundation at selected flood stages on the Blue River, Indian Creek, and Dyke Branch. The results of this study spatially interpolate information provided by U.S. Geological Survey gages, Kansas City Automated Local Evaluation in Real Time gages, and the National Weather Service flood-peak prediction service that comprise the Blue River flood-alert system and are a valuable tool for public officials and residents to minimize flood deaths and damage in Kansas City. To provide public access to the information presented in this report, a World Wide Web site (http://mo.water.usgs.gov/indep/kelly/blueriver) was created that displays the results of two-dimensional modeling between Hickman Mills Drive and 63rd Street, estimated flood-inundation maps for 13 flood stages, the latest gage heights, and National Weather Service stage forecasts for each forecast location within the study area. The results of a previous study of flood inundation on the Blue River from 63rd Street to the mouth also are available. In addition the full text of this report, all tables and maps are available for download (http://pubs.usgs.gov/sir/2008/5068). Thirteen flood-inundation maps were produced at 2-foot intervals for water-surface elevations from 763.8 to 787.8 feet referenced to the Blue River at the 63rd Street Automated Local Evaluation in Real Time stream gage operated by the city of Kansas City, Missouri. Each map is associated with gages at Kenneth Road, Blue Ridge Boulevard, Kansas City (at Bannister Road), U.S. Highway 71, and 63rd Street on the Blue River, and at 103rd Street on Indian Creek. The National Weather Service issues peak stage forecasts for Blue Ridge Boulevard, Kansas City (at Bannister Road), U.S. Highway 71, and 63rd Street during floods. A two-dimensional depth-averaged flow model simulated flooding within a hydraulically complex, 5.6-mile study reach of the Blue River between Hickman Mills Drive and 63rd Street. Hydraulic simulation of the study reach provided information for the estimated flood-inundation maps and water-velocity magnitude and direction maps. Flood profiles of the upper Blue River between the U.S. Geological Survey streamflow gage at Kenneth Road and Hickman Mills Drive were developed from water-surface elevations calculated using Federal Emergency Management Agency flood-frequency discharges and 2006 stage-discharge ratings at U.S. Geological Survey streamflow gages. Flood profiles between Hickman Mills Drive and 63rd Street were developed from two-dimensional hydraulic modeling conducted for this study. Flood profiles of Indian Creek between the Kansas-Missouri border and the mouth were developed from water-surface elevations calculated using current stage-discharge ratings at the U.S. Geological Survey streamflow gage at 103rd Street, and water-surface slopes derived from Federal Emergency Management Agency flood-frequency stage-discharge relations. Mapped flood water-surface elevations at the mouth of Dyke Branch were set equal to the flood water-surface elevations of Indian Creek at the Dyke Branch mouth for all Indian Creek water-surface elevations; water-surface elevation slopes were derived from Federal Emergency Management Agency flood-frequency stage-discharge relations.

Base (100-year) flood elevations for selected sites in Livingston County, Missouri

USGS Publications Warehouse

Southard, Rodney E.; Richards, Joseph M.

2002-01-01

The primary criteria for community participation in the National Flood Insurance Program is the adoption and enforcement of floodplain management requirements that minimize the potential for flood damages to existing and proposed development in flood-hazard areas. This report provides base flood elevations (BFE) for a 100-year recurrence-interval flood for use in the management and regulation of 18 flood-hazard areas designated by the Federal Emergency Management Agency as approximate Zone A areas in Livingston County, Missouri. The one-dimensional surface-water flow models HEC-RAS and Water-Surface PROfile (WSPRO) were used to compute base (100-year) flood elevations for 18 Zone A sites. The HEC-RAS model was used at BFE sites 1 to 6, 9, 10, and 15 to 18. The WSPRO model was used at BFE sites 7, 8, and 11 to 14. The 18 sites are all located in Livingston County, Missouri, at U.S., State, or County road crossings, and the base flood elevation was determined at the upstream side of each crossing. The base (100-year) flood elevations for BFE 1, 2, and 3 on Shoal Creek at Dawn and Shoal Creek Drainage Ditch near Dawn are 701.0, 701.0, and 696.5 feet, respectively. The base (100-year) flood elevations for BFE 4 and 5 on Indian Branch near Sampsel and a tributary to Indian Branch near Sampsel are 711.7 and 755.4 feet, respectively. Site BFE 6 is located on Honey Creek near Farmersville and the base (100-year) flood elevation for this site is 730.8 feet. One site (BFE 7) is located on No Creek near Farmersville. The base (100-year) flood elevation for this site is 731.3 feet. Site BFE 8 is located on Crooked Creek near Chillicothe and the base (100-year) elevation is 716.4 feet. One site (BFE 9) is located on a tributary to Coon Creek at Chillicothe. The base (100-year) flood elevation for this site is 734.9 feet. Two sites (BFE 10 and 11) are located on Blackwell Branch at Chillicothe. The base (100-year) flood elevation for BFE 10 is 738.9 feet and for BFE 11 is 701.7 feet. The base (100-year) flood elevation for BFE 12 on Medicine Creek near Chula is 721.7 feet. Sites BFE 13 and 15 are on Muddy Creek and for BFE 14 is on Little Muddy Creek near Chula. The base (100-year) flood elevations for BFE 13 and 15 are 733.0 and 717.9 feet, respectively and for BFE 14 is 734.6 feet. Downstream from BFE 12 is site BFE 16 on Medicine Creek near Wheeling. The base (100-year) flood elevation for site BFE 16 is 686.1 feet. One site (BFE 17) is located on Campbell Creek near Bedford. The base (100-year) flood elevation at this site is 691.8 feet. Site BFE 18 is located on Towstring Creek near Hale. The base (100-year) flood elevation for site BFE 18 is 667.4 feet.

Flood recovery maps for the White River in Bethel, Stockbridge, and Rochester, Vermont, and the Tweed River in Stockbridge and Pittsfield, Vermont, 2014

USGS Publications Warehouse

Olson, Scott A.

2015-01-01

Eighteen high-water marks from Tropical Storm Irene were available along the studied reaches. The discharges in the Tropical Storm Irene HEC–RAS model were adjusted so that the resulting water-surface elevations matched the high-water mark elevations along the study reaches. This allowed for an estimation of the water-surface profile throughout the study area resulting from Tropical Storm Irene. From a comparison of the estimated water-surface profile of Tropical Storm Irene to the water-surface profiles of the 1- and 0.2-percent AEP floods, it was determined that the high-water elevations resulting from Tropical Storm Irene exceeded the estimated 1-percent AEP flood throughout the White River and Tweed River study reaches and exceeded the estimated 0.2-percent AEP flood in 16.7 of the 28.6 study reach miles. The simulated water-surface profiles were then combined with a geographic information system digital elevation model derived from light detection and ranging (lidar) data having a 18.2-centimeter vertical accuracy at the 95-percent confidence level and 1-meter horizontal resolution to delineate the area flooded for each water-surface profile.

77 FR 15664 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-16

... table provided here represents the flooding sources, location of referenced elevations, and effective and modified elevations for the City of Cadiz, Kentucky. Specifically, it addresses the flooding... Cadiz, Kentucky'' addressed the flooding sources Little River (backwater effects from Lake Barkley) and...

The 3D Elevation Program—Flood risk management

USGS Publications Warehouse

Carswell, William J.; Lukas, Vicki

2018-01-25

Flood-damage reduction in the United States has been a longstanding but elusive societal goal. The national strategy for reducing flood damage has shifted over recent decades from a focus on construction of flood-control dams and levee systems to a three-pronged strategy to (1) improve the design and operation of such structures, (2) provide more accurate and accessible flood forecasting, and (3) shift the Federal Emergency Management Agency (FEMA) National Flood Insurance Program to a more balanced, less costly flood-insurance paradigm. Expanding the availability and use of high-quality, three-dimensional (3D) elevation information derived from modern light detection and ranging (lidar) technologies to provide essential terrain data poses a singular opportunity to dramatically enhance the effectiveness of all three components of this strategy. Additionally, FEMA, the National Weather Service, and the U.S. Geological Survey (USGS) have developed tools and joint program activities to support the national strategy.The USGS 3D Elevation Program (3DEP) has the programmatic infrastructure to produce and provide essential terrain data. This infrastructure includes (1) data acquisition partnerships that leverage funding and reduce duplicative efforts, (2) contracts with experienced private mapping firms that ensure acquisition of consistent, low-cost 3D elevation data, and (3) the technical expertise, standards, and specifications required for consistent, edge-to-edge utility across multiple collection platforms and public access unfettered by individual database designs and limitations.High-quality elevation data, like that collected through 3DEP, are invaluable for assessing and documenting flood risk and communicating detailed information to both responders and planners alike. Multiple flood-mapping programs make use of USGS streamflow and 3DEP data. Flood insurance rate maps, flood documentation studies, and flood-inundation map libraries are products of these programs.

Methodology and implications of maximum paleodischarge estimates for mountain channels, upper Animas River basin, Colorado, U.S.A.

USGS Publications Warehouse

Pruess, J.; Wohl, E.E.; Jarrett, R.D.

1998-01-01

Historical and geologic records may be used to enhance magnitude estimates for extreme floods along mountain channels, as demonstrated in this study from the San Juan Mountains of Colorado. Historical photographs and local newspaper accounts from the October 1911 flood indicate the likely extent of flooding and damage. A checklist designed to organize and numerically score evidence of flooding was used in 15 field reconnaissance surveys in the upper Animas River valley of southwestern Colorado. Step-backwater flow modeling estimated the discharges necessary to create longitudinal flood bars observed at 6 additional field sites. According to these analyses, maximum unit discharge peaks at approximately 1.3 m3 s-1 km-2 around 2200 m elevation, with decreased unit discharges at both higher and lower elevations. These results (1) are consistent with Jarrett's (1987, 1990, 1993) maximum 2300-m elevation limit for flash-flooding in the Colorado Rocky Mountains, and (2) suggest that current Probable Maximum Flood (PMF) estimates based on a 24-h rainfall of 30 cm at elevations above 2700 m are unrealistically large. The methodology used for this study should be readily applicable to other mountain regions where systematic streamflow records are of short duration or nonexistent.

78 FR 27 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-02

...-2012-0003] Final Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Final rule. SUMMARY: Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs are made... effect in order to qualify or remain qualified for participation in the National Flood Insurance Program...

75 FR 78926 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-17

...-2010-0003] Final Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Final rule. SUMMARY: Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs are made... effect in order to qualify or remain qualified for participation in the National Flood Insurance Program...

77 FR 74610 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-17

...-2012-0003] Final Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Final rule. SUMMARY: Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs are made... effect in order to qualify or remain qualified for participation in the National Flood Insurance Program...

Water-surface elevations and channel characteristics for a selected reach of the Applegate River, Jackson County, Oregon

USGS Publications Warehouse

Harris, David Dell; Alexander, Clyde W.

1970-01-01

In land-use planning for the Applegate River and its flood plain, consideration should be given to (1) preservation of the recreational attributes of the area, (2) allowance for optimum development of the flood plain's natural resources, and (3) protection of the rights of private landowners. Major factors that influence evaluation of the above considerations are the elevations and characteristics of floods. Heretofore, such flood data for the Applegate River have been inadequate to evaluate the flood potential or to use as a basis for delineating reasonable land-use zones. Therefore, at the request of Jackson County, this study was made to provide flood elevations, water-surface profiles, and channel characteristics (geometry and slope) for a reach of the Applegate River from the Jackson-Josephine County line upstream to the Applegate damsite (fig. 1). A similar study was previously made for reaches of adjacent Rogue River and Elk Creek (Harris, 1970).

Flood of May 2006 in York County, Maine

USGS Publications Warehouse

Stewart, Gregory J.; Kempf, Joshua P.

2008-01-01

A stalled low-pressure system over coastal New England on Mother's Day weekend, May 13-15, 2006, released rainfall in excess of 15 inches. This flood (sometimes referred to as the 'Mother's Day flood') caused widespread damage to homes, businesses, roads, and structures in southern Maine. The damage to public property in York County was estimated to be $7.5 million. As a result of these damages, a presidential disaster declaration was enacted on May 25, 2006, for York County, Maine. Peak-flow recurrence intervals for eight of the nine streams studied were calculated to be greater than 500 years. The peak-flow recurrence interval of the remaining stream was calculated to be between a 100-year and a 500-year interval. This report provides a detailed description of the May 2006 flood in York County, Maine. Information is presented on peak streamflows and peak-flow recurrence intervals on nine streams, peak water-surface elevations for 80 high-water marks at 25 sites, hydrologic conditions before and after the flood, comparisons with published Flood Insurance Studies, and places the May 2006 flood in context with historical floods in York County. At sites on several streams, differences were observed between peak flows published in the Flood Insurance Studies and those calculated for this study. The differences in the peak flows from the published Flood Insurance Studies and the flows calculated for this report are within an acceptable range for flows calculated at ungaged locations, with the exception of those for the Great Works River and Merriland River. For sites on the Mousam River, Blacksmith Brook, Ogunquit River, and Cape Neddick River, water-surface elevations from Flood Insurance Studies differed with documented water-surface elevations from the 2006 flood.

Flood of April 2-3, 2005, Neversink River Basin, New York

USGS Publications Warehouse

Suro, Thomas P.; Firda, Gary D.

2006-01-01

Heavy rain on April 2-3, 2005 produced rainfall amounts of 3 inches to almost 6 inches within a 36-hour period throughout the Delaware River basin. Major flooding occurred in the East and West Branches of the Delaware River and their tributaries, the main stem of the Delaware River and the Neversink River, a major tributary to the Delaware River. The resultant flooding damaged hundreds of homes, caused millions of dollars in damage to infrastructure in Orange and Sullivan Counties, and forced more than 1,000 residents to evacuate their homes. A total of 20 New York counties were declared Federal disaster areas. Some of the most extensive flooding occurred along the Neversink and Delaware Rivers in Orange and Sullivan Counties, New York. Disaster recovery assistance from the April 2005 flooding in New York stood at almost $35 million in 2005, at which time more than 3,400 New Yorkers had registered for Federal aid. All U.S. Geological Survey stream-gaging stations on the Neversink River below the Neversink Reservoir recorded peak water-surface elevations higher than those recorded during the September 2004 flooding. Peak water-surface elevations at some study sites on the Neversink River exceeded the 500-year flood elevation as documented in flood-insurance studies by the Federal Emergency Management Agency. Flood peaks at some long-term U.S. Geological Survey stream-gaging stations were the highest ever recorded. Several U.S. Geological Survey stream-gaging stations on the Delaware River also recorded peak water-surface elevations that exceeded those recorded during the September 2004 flooding.

Estimating Paleoflood Magnitude From Tree-Ring Anatomy and the Height of Abrasion Scars

NASA Astrophysics Data System (ADS)

Yanosky, T. M.; Jarrett, R. D.

2003-12-01

Evidence of floods preserved in the growth rings of trees can be used to extend the historical record of flooding or to estimate the magnitude of extraordinary floods on ungaged streams. Floods that damage the aerial parts of trees during the growing season sometimes induce striking anatomical changes in subsequent growth of rings in the lower trunk. In ring-porous species, this growth most commonly produces concentric bands of atypically large vessels within the latewood. The number and diameter of anomalous vessels seem positively related to the amount of flood damage, and thus can be used to refine estimates of flood magnitude when also considering the position of the tree relative to the channel and its approximate height during the flood. Floods of long duration on low-gradient streams are less likely to damage trees directly, but prolonged root flooding often results in the formation of narrow rings with atypically small vessels; shorter-duration floods, sometimes inundating roots for as little as several days, are followed by the production of fibers (non-conducting cells) with large lumens and thin walls that appear as light-colored bands compared to earlier-formed tissue. In these instances, a series of trees increasingly distant from the channel can be used to estimate a minimum flood elevation. Abrasion scars from flood-borne debris often are the most easily observed evidence of flood damage and, like anatomical abnormalities, can be precisely dated. The relation between the heights of scars and maximum flood stages depends in part upon channel slope. Previous studies have indicated that scar heights along low-gradient streams are the same or slightly lower than maximum flood elevations. Along the high-gradient (6% maximum slope) Buffalo Creek, Colorado USA, scar heights measured in 102 trees following a flood in 1996 ranged from -0.6 to +1.5 m relative to the actual crest elevation. Scar elevations exceeding flood elevations by 3-4 m, however, were observed following a flood in 2002 along a small Colorado stream with slopes ranging from 6 to 15%.

Base (100-year) flood elevations for selected sites in Marion County, Missouri

USGS Publications Warehouse

Southard, Rodney E.; Wilson, Gary L.

1998-01-01

The primary requirement for community participation in the National Flood Insurance Program is the adoption and enforcement of floodplain management requirements that minimize the potential for flood damages to new construction and avoid aggravating existing flooding conditions. This report provides base flood elevations (BFE) for a 100-year recurrence flood for use in the management and regulation of 14 flood-hazard areas designated by the Federal Emergency Management Agency as approximate Zone A areas in Marion County, Missouri. The one-dimensional surface-water flow model, HEC-RAS, was used to compute the base (100-year) flood elevations for the 14 Zone A sites. The 14 sites were located at U.S., State, or County road crossings and the base flood elevation was determined at the upstream side of each crossing. The base (100-year) flood elevations for BFE 1, 2, and 3 on the South Fork North River near Monroe City, Missouri, are 627.7, 579.2, and 545.9 feet above sea level. The base (100-year) flood elevations for BFE 4, 5, 6, and 7 on the main stem of the North River near or at Philadelphia and Palmyra, Missouri, are 560.5, 539.7, 504.2, and 494.4 feet above sea level. BFE 8 is located on Big Branch near Philadelphia, a tributary to the North River, and the base (100-year) flood elevation at this site is 530.5 feet above sea level. One site (BFE 9) is located on the South River near Monroe City, Missouri. The base (100-year) flood elevation at this site is 619.1 feet above sea level. Site BFE 10 is located on Bear Creek near Hannibal, Missouri, and the base (100-year) elevation is 565.5 feet above sea level. The four remaining sites (BFE 11, 12, 13, and 14) are located on the South Fabius River near Philadelphia and Palmyra, Missouri. The base (100-year) flood elevations for BFE 11, 12, 13, and 14 are 591.2, 578.4, 538.7, and 506.9 feet above sea level.

Teton Dam flood of June 1976, Firth quadrangle, Idaho

USGS Publications Warehouse

Hubbard, Larry L.; Bartells, John H.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Firth quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Rose quadrangle, Idaho

USGS Publications Warehouse

Bartells, John H.; Hubbard, Larry L.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Rose quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Rexburg quadrangle, Idaho

USGS Publications Warehouse

Harenberg, W.A.; Bigelow, B.B.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification on these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Rexburg quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Deer Parks quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Bennett, C. Michael; Records, Andrew W.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Deer Parks quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Parker quadrangle, Idaho

USGS Publications Warehouse

Thomas, Cecil Albert; Ray, Herman A.

1976-01-01

The failure of Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls, Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Parker quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, St. Anthony quadrangle, Idaho

USGS Publications Warehouse

Thomas, Cecil A.; Ray, Herman A.; Matthai, Howard F.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the St. Anthony quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Woodville quadrangle, Idaho

USGS Publications Warehouse

Matthai, Howard F.; Ray, Herman A.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Woodville quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Menan Buttes quadrangle, Idaho

USGS Publications Warehouse

Thomas, Cecil A.; Ray, Herman A.; Harenberg, William A.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Menan Buttes quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Idaho Falls South quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Matthai, Howard F.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Idaho Falls South quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Lewisville quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Bigelow, Bruce B.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Lewisville quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Idaho Falls North quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Matthai, Howard F.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Idaho Falls North quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Pingree quadrangle, Idaho

USGS Publications Warehouse

Hubbard, Larry L.; Bartells, John H.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Pingree quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Blackfoot quadrangle, Idaho

USGS Publications Warehouse

Bartells, J.H.; Hubbard, Larry L.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Blackfoot quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Moreland quadrangle, Idaho

USGS Publications Warehouse

Hubbard, Larry L.; Bartells, John H.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The aea covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Moreland quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Rigby quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Bigelow, Bruce B.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Rigby quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Newdale quadrangle, Idaho

USGS Publications Warehouse

Ray, Herman A.; Matthai, Howard F.; Thomas, Cecil A.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Newdale quadrangle. (Woodard-USGS)

Teton Dam flood of June 1976, Moody quadrangle, Idaho

USGS Publications Warehouse

Harenberg, William A.; Bigelow, Bruce B.

1976-01-01

The failure of the Teton Dam caused extreme flooding along the Teton River, Henrys Fork, and Snake River in southeastern Idaho on June 5-8, 1976. No flooding occurred downstream from American Falls Reservoir. The inundated areas and maximum water-surface elevations are shown in a series of 17 hydrologic atlases. The area covered by the atlases extends from Teton Dam downstream to American Falls Reservoir, a distance of 100 miles. The extent of flooding shown on the maps was obtained by field inspections and aerial photographs made during and immediately after the flood. There may be small isolated areas within the boundaries shown that were not flooded, but the identification of these sites was beyond the scope of the study. The elevation data shown are mean-sea-level elevations of high-water marks identified in the field. This particular map (in the 17-map series) shows conditions in the Moody quadrangle. (Woodard-USGS)

Flood of April and May 2008 in Northern Maine

USGS Publications Warehouse

Lombard, Pamela J.

2010-01-01

Severe flooding occurred in Aroostook and Penobscot Counties in northern Maine between April 28 and May 1, 2008, and was most extreme in the town of Fort Kent. Peak streamflows in northern Aroostook County were the result of a persistent heavy snowpack that caused high streamflows when it quickly melted during the third week of April 2008. Snowmelt was followed by from two to four inches of rainfall over a 2-day period in northern Maine. Peak water-surface elevations resulting from the flood were obtained from 13 continuous-record streamgages and 63 surveyed high-water marks in Aroostook and Penobscot Counties. Peak streamflows were obtained from 20 sites on 15 streams through stage/discharge rating curves or hydraulic flow models. Peak water-surface elevations and streamflows were the highest ever recorded at seven continuous-record streamgages, which had between 25 and 84 years of record in northern Aroostook County. The annual exceedance probability (the percent chance of exceeding the streamflow recorded during the April/May 2008 flood during any given year) at six streamgages in northern Maine was equal to or less than 1 percent. Data from flood-insurance studies published by the Federal Emergency Management Agency were available for five of the locations analyzed for the April/May 2008 flood and were compared to streamflows and observed peak water-surface elevations from the 2008 flood. Water-surface elevations that would be expected given the observed flow as applied to the effective flood insurance studies ranged from between 1 and 4 feet from the water-surface elevations observed during the 2008 flood. Differences were likely the result of up to 30 years of additional data for the calculation of recurrence intervals and the fact that hydraulic models used for the models had not previously been calibrated to a flood of this magnitude.

Effect of bank protection measures, Stehekin River, Chelan County, Washington

USGS Publications Warehouse

Nelson, L.M.

1986-01-01

An investigation of the lower Stehekin River was conducted to study the effects on flood elevations and velocities from four bank protection and flood prevention measures that are being contemplated as a means of reducing erosional losses of river bank property. These measures are: bank armoring, armored revetment levees, spur dikes, and redevelopment of old cutoff channels. The banks at seven study sites could be armored without adverse effect on the flood velocities and elevations. The largest increases due to armoring--up to 1.6 ft/sec in velocity and 1 ft in elevation--occurred in the vicinity of sites 5, 6, and 7 where the gradient of the river channel is about 50 ft/mi and the velocities are high to begin with (about 6 to 13 ft/sec). The use of a levee in conjunction with armoring on the northeast bank from sites 5 to 7 would increase the velocities as much as 2.8 ft/sec and increase the elevation as much as 1 ft, but it would also provide some flood protection to the east bank, which is frequently inundated. Spur dikes were considered a practical alternative only at site 3, where reduced bank erosion may occur without aggravating flood inundation or erosion elsewhere. The rerouting of flood flow through an old cutoff channel near site 1 increased the velocity by 3.2 ft/sec and the elevation by 1 ft for the 100-year flood; however, it would move floodwater away from residential property where bank erosion is a problem. The few other old channels that shortcut river bends where much erosion occurs are apparently already part of the channel during floods. (Author 's abstract)

The Upper Mississippi River floodscape: spatial patterns of flood inundation and associated plant community distributions

USGS Publications Warehouse

DeJager, Nathan R.; Rohweder, Jason J.; Yin, Yao; Hoy, Erin E.

2016-01-01

Questions How is the distribution of different plant communities associated with patterns of flood inundation across a large floodplain landscape? Location Thirty-eight thousand nine hundred and seventy hectare of floodplain, spanning 320 km of the Upper Mississippi River (UMR). Methods High-resolution elevation data (Lidar) and 30 yr of daily river stage data were integrated to produce a ‘floodscape’ map of growing season flood inundation duration. The distributions of 16 different remotely sensed plant communities were quantified along the gradient of flood duration. Results Models fitted to the cumulative frequency of occurrence of different vegetation types as a function of flood duration showed that most types exist along a continuum of flood-related occurrence. The diversity of community types was greatest at high elevations (0–10 d of flooding), where both upland and lowland community types were found, as well as at very low elevations (70–180 d of flooding), where a variety of lowland herbaceous communities were found. Intermediate elevations (20–60 d of flooding) tended to be dominated by floodplain forest and had the lowest diversity of community types. Conclusions Although variation in flood inundation is often considered to be the main driver of spatial patterns in floodplain plant communities, few studies have quantified flood–vegetation relationships at broad scales. Our results can be used to identify targets for restoration of historical hydrological regimes or better anticipate hydro-ecological effects of climate change at broad scales.

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Flooding on self-elevating and surface type units. 174... Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or... superstructure deck where superstructures are fitted must be assumed to be subject to simultaneous flooding. (b...

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Flooding on self-elevating and surface type units. 174... Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or... superstructure deck where superstructures are fitted must be assumed to be subject to simultaneous flooding. (b...

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Flooding on self-elevating and surface type units. 174... Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or... superstructure deck where superstructures are fitted must be assumed to be subject to simultaneous flooding. (b...

Evaluation of the flood hydrology in the Colorado Front Range using precipitation, streamflow, and paleoflood data for the Big Thompson River basin

USGS Publications Warehouse

Jarrett, R.D.; Costa, J.E.

1988-01-01

A multidisciplinary study of precipitation and streamflow data and paleohydrologic studies of channel features was made to analyze the flood hydrology of foothill and mountain streams in the Front Range of Colorado, with emphasis on the Big Thompson River basin, because conventional hydrologic analyses do not adequately characterize the flood hydrology. In the foothills of Colorado, annual floodflows are derived from snowmelt at high elevations in the mountain regions, from rainfall at low elevation in the plains or plateau regions, or from a combination of rain falling on snow or mixed population hydrology. Above approximately 7,500 ft, snowmelt dominates; rain does not contribute to the flood potential. Regional flood-frequency relations were developed and compared with conventional flood-estimating technique results, including an evaluation of the magnitude and frequency of the probable maximum flood. Evaluation of streamflow data and paleoflood investigations provide an alternative for evaluating flood hydrology and the safety of dams. The study indicates the need for additional data collection and research to understand the complexities of the flood hydrology in mountainous regions, especially its effects on flood-plain management and the design of structures in the flood plain. (USGS)

Contribution of river floods, hurricanes, and cold fronts to elevation change in a deltaic floodplain, northern Gulf of Mexico, USA

NASA Astrophysics Data System (ADS)

Bevington, Azure E.; Twilley, Robert R.; Sasser, Charles E.; Holm, Guerry O.

2017-05-01

Deltas are globally important locations of diverse ecosystems, human settlement, and economic activity that are threatened by reductions in sediment delivery, accelerated sea level rise, and subsidence. Here we investigated the relative contribution of river flooding, hurricanes, and cold fronts on elevation change in the prograding Wax Lake Delta (WLD). Sediment surface elevation was measured across 87 plots, eight times from February 2008 to August 2011. The high peak discharge river floods in 2008 and 2011 resulted in the greatest mean net elevation gain of 5.4 to 4.9 cm over each flood season, respectively. The highest deltaic wetland sediment retention (13.5% of total sediment discharge) occurred during the 2008 river flood despite lower total and peak discharge compared to 2011. Hurricanes Gustav and Ike resulted in a total net elevation gain of 1.2 cm, but the long-term contribution of hurricane derived sediments to deltaic wetlands was estimated to be just 22% of the long-term contribution of large river floods. Winter cold front passage resulted in a net loss in elevation that is equal to the elevation gain from lower discharge river floods and was consistent across years. This amount of annual loss in elevation from cold fronts could effectively negate the long-term land building capacity within the delta without the added elevation gain from both high and low discharge river floods. The current lack of inclusion of cold front elevation loss in most predictive numerical models likely overestimates the land building capacity in areas that experience similar forcings to WLD.

An Agent-Based Model of Evolving Community Flood Risk.

PubMed

Tonn, Gina L; Guikema, Seth D

2018-06-01

Although individual behavior plays a major role in community flood risk, traditional flood risk models generally do not capture information on how community policies and individual decisions impact the evolution of flood risk over time. The purpose of this study is to improve the understanding of the temporal aspects of flood risk through a combined analysis of the behavioral, engineering, and physical hazard aspects of flood risk. Additionally, the study aims to develop a new modeling approach for integrating behavior, policy, flood hazards, and engineering interventions. An agent-based model (ABM) is used to analyze the influence of flood protection measures, individual behavior, and the occurrence of floods and near-miss flood events on community flood risk. The ABM focuses on the following decisions and behaviors: dissemination of flood management information, installation of community flood protection, elevation of household mechanical equipment, and elevation of homes. The approach is place based, with a case study area in Fargo, North Dakota, but is focused on generalizable insights. Generally, community mitigation results in reduced future damage, and individual action, including mitigation and movement into and out of high-risk areas, can have a significant influence on community flood risk. The results of this study provide useful insights into the interplay between individual and community actions and how it affects the evolution of flood risk. This study lends insight into priorities for future work, including the development of more in-depth behavioral and decision rules at the individual and community level. © 2017 Society for Risk Analysis.

Flood of September 18-19, 2004 in the Upper Delaware River Basin, New York

USGS Publications Warehouse

Brooks, Lloyd T.

2005-01-01

The interaction between the remnants of tropical depression Ivan and a frontal boundary in the upper Delaware River basin on September 18-19, 2004, produced 4 to more than 6 inches of rainfall over a 5-county area within a 24-hour period. Significant flooding occurred on the East Branch Delaware River and its tributaries, and the main stem of the Delaware River. The resultant flooding damaged more than 100 homes and displaced more than 1,000 people. All of the counties within the basin were declared Federal disaster areas, but flood damage in New York was most pronounced in Delaware, Orange, and Sullivan Counties. Flood damage totaled more than $10 million. Peak water-surface elevations at some study sites in the basin exceeded the 500-year flood elevation as documented in flood-insurance studies by the Federal Emergency Management Agency. Flood peaks at some long-term U.S. Geological Survey (USGS) streamflow-gaging stations were the highest ever recorded.

Floods of 1971 and 1972 on Glover Creek and Little River in southeastern Oklahoma

USGS Publications Warehouse

Thomas, Wilbert O.; Corley, Robert K.

1973-01-01

Heavy rains of December 9-10, 1971, and Oct. 30-31, 1972, caused outstanding floods on Glover Creek and Little River in McCurtain County in southeastern Oklahoma. This report presents hydrologic data that document the extent of flooding, flood profiles, and frequency of flooding on reaches of both streams. The data presented provide a technical basis for formulating effective flood-plain zoning that will minimize existing and future flood problems. The report also can be useful for locating waste-disposal and water-treatment facilities, and for the development of recreational areas. The area studied includes the reach of Little River on the Garvin and Idabel 7 1/2-minute quadrangles (sheet 1) and the reach of Glover Creek on the southwest quarter of the Golden 15-minute quadrangle (sheet 2). The flood boundaries delineated on the maps are the limits of flooding during the December 1971 and October 1972 floods. Any attempt to delineate the flood boundaries on streams in the study area other than Glover Creek and Little River was considered to be beyond the scope of this report. The general procedure used in defining the flood boundaries was to construct the flood profiles from high-water marks obtained by field surveys and by records at three stream-gaging stations (two on Little River and one on Glover Creek.). The extent of flooding was delineated on the topographic maps by using the flood profiles to define the flood elevations at various points along the channel and locating the elevations on the map by interpolating between contours (lines of equal ground elevation). In addition, flood boundaries were defined in places by field survey, aerial photographs, and information from local residents. The accuracy of the flood boundaries is consistent with the scale and contour interval of the maps (1 inch = 2,000 feet; contour interval 10 and 20 feet), which means the flood boundaries are drawn as accurately as possible on maps having 10- and 20-foot contour intervals.

Investigating flood susceptible areas in inaccessible regions using remote sensing and geographic information systems.

PubMed

Lim, Joongbin; Lee, Kyoo-Seock

2017-03-01

Every summer, North Korea (NK) suffers from floods, resulting in decreased agricultural production and huge economic loss. Besides meteorological reasons, several factors can accelerate flood damage. Environmental studies about NK are difficult because NK is inaccessible due to the division of Korea. Remote sensing (RS) can be used to delineate flood inundated areas in inaccessible regions such as NK. The objective of this study was to investigate the spatial characteristics of flood susceptible areas (FSAs) using multi-temporal RS data and digital elevation model data. Such study will provide basic information to restore FSAs after reunification. Defining FSAs at the study site revealed that rice paddies with low elevation and low slope were the most susceptible areas to flood in NK. Numerous sediments from upper streams, especially streams through crop field areas on steeply sloped hills, might have been transported and deposited into stream channels, thus disturbing water flow. In conclusion, NK floods may have occurred not only due to meteorological factors but also due to inappropriate land use for flood management. In order to mitigate NK flood damage, reforestation is needed for terraced crop fields. In addition, drainage capacity for middle stream channel near rice paddies should be improved.

76 FR 46715 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-03

... table provided here represents the flooding sources, location of referenced elevations, effective and.... Specifically, it addresses the following flooding sources: Cabin Branch, Franklin Branch, Hall Creek, Little... Incorporated Areas'' addressed the following flooding sources: Cabin Branch, Franklin Branch, Little Patuxent...

76 FR 9714 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-22

..., FEMA published in the Federal Register a proposed rule that included an erroneous Base Flood Elevation... as 355 feet, referenced to the North American Vertical Datum of 1988. DATES: Comments pertaining to... (FEMA) publishes proposed determinations of Base (1% annual-chance) Flood Elevations (BFEs) and modified...

76 FR 3596 - Proposed Flood Elevation Determinations for York County, Maine (All Jurisdictions)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

...-2008-0020; Internal Agency Docket No. FEMA-B-1066] Proposed Flood Elevation Determinations for York... notice of proposed rulemaking concerning proposed flood elevation determinations for York County, Maine...: Luis Rodriguez, Chief, Engineering Management Branch, Federal Insurance and Mitigation Administration...

Ohio River backwater flood-inundation maps for the Saline and Wabash Rivers in southern Illinois

USGS Publications Warehouse

Murphy, Elizabeth A.; Sharpe, Jennifer B.; Soong, David T.

2012-01-01

Digital flood-inundation maps for the Saline and Wabash Rivers referenced to elevations on the Ohio River in southern Illinois were created by the U.S. Geological Survey (USGS). The inundation maps, accessible through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (gage heights) at the USGS streamgage at Ohio River at Old Shawneetown, Illinois-Kentucky (station number 03381700). Current gage height and flow conditions at this USGS streamgage may be obtained on the Internet at http://waterdata.usgs.gov/usa/nwis/uv?03381700. In addition, this streamgage is incorporated into the Advanced Hydrologic Prediction Service (AHPS) flood warning system (http://water.weather.gov/ahps/) by the National Weather Service (NWS). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. That NWS forecasted peak-stage information, also shown on the Ohio River at Old Shawneetown inundation Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, eight water-surface elevations were mapped at 5-foot (ft) intervals referenced to the streamgage datum ranging from just above the NWS Action Stage (31 ft) to above the maximum historical gage height (66 ft). The elevations of the water surfaces were compared to a Digital Elevation Model (DEM) by using a Geographic Information System (GIS) in order to delineate the area flooded at each water level. These maps, along with information on the Internet regarding current gage heights from USGS streamgages and forecasted stream stages from the NWS, provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

Updating flood maps efficiently using existing hydraulic models, very-high-accuracy elevation data, and a geographic information system; a pilot study on the Nisqually River, Washington

USGS Publications Warehouse

Jones, Joseph L.; Haluska, Tana L.; Kresch, David L.

2001-01-01

A method of updating flood inundation maps at a fraction of the expense of using traditional methods was piloted in Washington State as part of the U.S. Geological Survey Urban Geologic and Hydrologic Hazards Initiative. Large savings in expense may be achieved by building upon previous Flood Insurance Studies and automating the process of flood delineation with a Geographic Information System (GIS); increases in accuracy and detail result from the use of very-high-accuracy elevation data and automated delineation; and the resulting digital data sets contain valuable ancillary information such as flood depth, as well as greatly facilitating map storage and utility. The method consists of creating stage-discharge relations from the archived output of the existing hydraulic model, using these relations to create updated flood stages for recalculated flood discharges, and using a GIS to automate the map generation process. Many of the effective flood maps were created in the late 1970?s and early 1980?s, and suffer from a number of well recognized deficiencies such as out-of-date or inaccurate estimates of discharges for selected recurrence intervals, changes in basin characteristics, and relatively low quality elevation data used for flood delineation. FEMA estimates that 45 percent of effective maps are over 10 years old (FEMA, 1997). Consequently, Congress has mandated the updating and periodic review of existing maps, which have cost the Nation almost 3 billion (1997) dollars. The need to update maps and the cost of doing so were the primary motivations for piloting a more cost-effective and efficient updating method. New technologies such as Geographic Information Systems and LIDAR (Light Detection and Ranging) elevation mapping are key to improving the efficiency of flood map updating, but they also improve the accuracy, detail, and usefulness of the resulting digital flood maps. GISs produce digital maps without manual estimation of inundated areas between cross sections, and can generate working maps across a broad range of scales, for any selected area, and overlayed with easily updated cultural features. Local governments are aggressively collecting very-high-accuracy elevation data for numerous reasons; this not only lowers the cost and increases accuracy of flood maps, but also inherently boosts the level of community involvement in the mapping process. These elevation data are also ideal for hydraulic modeling, should an existing model be judged inadequate.

Climate simulation and flood risk analysis for 2008-40 for Devils Lake, North Dakota

USGS Publications Warehouse

Vecchia, Aldo V.

2008-01-01

Devils Lake and Stump Lake in northeastern North Dakota receive surface runoff from a 3,810-square-mile drainage basin, and evaporation provides the only major water loss unless the lakes are above their natural spill elevation to the Sheyenne River. In September 2007, flow from Devils Lake to Stump Lake had filled Stump Lake and the two lakes consisted of essentially one water body with an elevation of 1,447.1 feet, about 3 feet below the existing base flood elevation (1,450 feet) and about 12 feet below the natural outlet elevation to the Sheyenne River (1,459 feet).Devils Lake could continue to rise, causing extensive additional flood damages in the basin and, in the event of an uncontrolled natural spill, downstream in the Red River of the North Basin. This report describes the results of a study conducted by the U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency, to evaluate future flood risk for Devils Lake and provide information for developing updated flood-insurance rate maps and planning flood-mitigation activities such as raising levees or roads.In about 1980, a large, abrupt, and highly significant increase in precipitation occurred in the Devils Lake Basin and elsewhere in the Northern Great Plains, and wetter-than-normal conditions have persisted through the present (2007). Although future precipitation is impossible to predict, paleoclimatic evidence and recent research on climate dynamics indicate the current wet conditions are not likely to end anytime soon. For example, there is about a 72-percent chance wet conditions will last at least 10 more years and about a 37-percent chance wet conditions will last at least 30 more years.A stochastic simulation model for Devils Lake and Stump Lake developed in a previous study was updated and used to generate 10,000 potential future realizations, or traces, of precipitation, evaporation, inflow, and lake levels given existing conditions on September 30, 2007, and randomly generated future duration of the current wet period. On the basis of the simulations, and assuming ice-free conditions and calm wind, the Devils Lake flood elevation for an annualized flood risk of 1 percent (analogous to a “100-year” riverine flood) was estimated to be 1,454.6 feet for a 10-year time horizon (2008­­­–17). Therefore, without adjusting for wind or ice, a residence near Devils Lake at elevation 1,454.6 feet has the same chance of being flooded sometime during the next 10 years as a residence at the edge of the 100-year flood plain along a river. Adjusting for the effects of wind or ice, which will increase the flood elevations for many locations near the lakes, was not within the scope of this study.

Direct local building inundation depth determination in 3-D point clouds generated from user-generated flood images

NASA Astrophysics Data System (ADS)

Griesbaum, Luisa; Marx, Sabrina; Höfle, Bernhard

2017-07-01

In recent years, the number of people affected by flooding caused by extreme weather events has increased considerably. In order to provide support in disaster recovery or to develop mitigation plans, accurate flood information is necessary. Particularly pluvial urban floods, characterized by high temporal and spatial variations, are not well documented. This study proposes a new, low-cost approach to determining local flood elevation and inundation depth of buildings based on user-generated flood images. It first applies close-range digital photogrammetry to generate a geo-referenced 3-D point cloud. Second, based on estimated camera orientation parameters, the flood level captured in a single flood image is mapped to the previously derived point cloud. The local flood elevation and the building inundation depth can then be derived automatically from the point cloud. The proposed method is carried out once for each of 66 different flood images showing the same building façade. An overall accuracy of 0.05 m with an uncertainty of ±0.13 m for the derived flood elevation within the area of interest as well as an accuracy of 0.13 m ± 0.10 m for the determined building inundation depth is achieved. Our results demonstrate that the proposed method can provide reliable flood information on a local scale using user-generated flood images as input. The approach can thus allow inundation depth maps to be derived even in complex urban environments with relatively high accuracies.

76 FR 43965 - Proposed Flood Elevation Determinations; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-22

... FR 70944. The table provided here represents the flooding sources, location of referenced elevations... Areas. Specifically, it addresses the flooding sources Cumberland River (Lake Barkley) and Tennessee... County, Kentucky, and Incorporated Areas'' addressed the flooding sources Cumberland River (Lake Barkley...

Topography- and nightlight-based national flood risk assessment in Canada

NASA Astrophysics Data System (ADS)

Elshorbagy, Amin; Bharath, Raja; Lakhanpal, Anchit; Ceola, Serena; Montanari, Alberto; Lindenschmidt, Karl-Erich

2017-04-01

In Canada, flood analysis and water resource management, in general, are tasks conducted at the provincial level; therefore, unified national-scale approaches to water-related problems are uncommon. In this study, a national-scale flood risk assessment approach is proposed and developed. The study focuses on using global and national datasets available with various resolutions to create flood risk maps. First, a flood hazard map of Canada is developed using topography-based parameters derived from digital elevation models, namely, elevation above nearest drainage (EAND) and distance from nearest drainage (DFND). This flood hazard mapping method is tested on a smaller area around the city of Calgary, Alberta, against a flood inundation map produced by the city using hydraulic modelling. Second, a flood exposure map of Canada is developed using a land-use map and the satellite-based nightlight luminosity data as two exposure parameters. Third, an economic flood risk map is produced, and subsequently overlaid with population density information to produce a socioeconomic flood risk map for Canada. All three maps of hazard, exposure, and risk are classified into five classes, ranging from very low to severe. A simple way to include flood protection measures in hazard estimation is also demonstrated using the example of the city of Winnipeg, Manitoba. This could be done for the entire country if information on flood protection across Canada were available. The evaluation of the flood hazard map shows that the topography-based method adopted in this study is both practical and reliable for large-scale analysis. Sensitivity analysis regarding the resolution of the digital elevation model is needed to identify the resolution that is fine enough for reliable hazard mapping, but coarse enough for computational tractability. The nightlight data are found to be useful for exposure and risk mapping in Canada; however, uncertainty analysis should be conducted to investigate the effect of the overglow phenomenon on flood risk mapping.

44 CFR 67.8 - Appeal procedure.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.8 Appeal procedure. (a) If a community appeals the proposed flood elevation...

Flood-inundation maps for the Yellow River at Plymouth, Indiana

USGS Publications Warehouse

Menke, Chad D.; Bunch, Aubrey R.; Kim, Moon H.

2016-11-16

Digital flood-inundation maps for a 4.9-mile reach of the Yellow River at Plymouth, Indiana (Ind.), were created by the U.S. Geological Survey (USGS) in cooperation with the Indiana Office of Community and Rural Affairs. The flood-inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage 05516500, Yellow River at Plymouth, Ind. Current conditions for estimating near-real-time areas of inundation using USGS streamgage information may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/uv?site_no=05516500. In addition, information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http:/water.weather.gov/ahps/). The NWS AHPS forecasts flood hydrographs at many sites that are often collocated with USGS streamgages, including the Yellow River at Plymouth, Ind. NWS AHPS-forecast peak-stage information may be used in conjunction with the maps developed in this study to show predicted areas of flood and forecasts of flood hydrographs at this site.For this study, flood profiles were computed for the Yellow River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the current stage-discharge relations at the Yellow River streamgage, in combination with the flood-insurance study for Marshall County (issued in 2011). The calibrated hydraulic model was then used to determine eight water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability flood profile elevation (flood elevation with recurrence intervals within 100 years) is within the calibrated water-surface elevations for comparison. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level.The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 05516500, Yellow River at Plymouth, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for postflood recovery efforts.

Flood of April 2-3, 2005, Esopus Creek Basin, New York

USGS Publications Warehouse

Suro, Thomas P.; Firda, Gary D.

2007-01-01

On April 2-3, 2005, heavy rain moved into southern New York and delivered rainfall amounts that ranged from about 2 in. to almost 6 in. within a 36-hour period. Significant flooding occurred on many small streams and tributaries in the area, and extensive flooding occurred on the Esopus and Roundout Creeks in Ulster and Greene Counties, New York. The flooding damaged many homes, caused millions of dollars worth of damage, and forced hundreds of residents to evacuate their homes. A total of 20 New York counties were declared Federal disaster areas. Disaster recovery assistance for those people affected stands at almost $35 million, according to the Federal Emergency Management Agency, as more than 3,400 New Yorkers registered for Federal aid. U.S. Geological Survey stream-gaging stations on the Esopus Creek above the Ashokan Reservoir at Allaben, N.Y., and below the Ashokan Reservoir at Mount Marion, N.Y., each recorded a new record maximum water-surface elevation and discharge for the respective periods of record as a result of this storm. The peak water-surface elevation and discharge recorded during the April 2-3, 2005, storm at the U.S. Geological Survey stream-gaging station on the Esopus Creek at Cold Brook, N.Y. were the third highest elevation and discharge since the station was put into operation in 1914. Most of the study sites along the Esopus Creek indicated water-surface elevations near the 50-year flood elevations, as documented in flood-insurance studies by the Federal Emergency Management Agency.

76 FR 26981 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-10

... table provided here represents the flooding sources, location of referenced elevations, effective and.... Specifically, it addresses the following flooding sources: Cache Creek, Cache Creek Left Bank Overflow, and... ``Unincorporated Areas of Yolo County, California'' addressed the flooding source Cache Creek Settling Basin. That...

76 FR 13570 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-14

.... The table provided here represents the flooding sources, location of referenced elevations, effective.... Specifically, it addresses the flooding source South Creek. DATES: Comments are to be submitted on or before... table, entitled ``Sanpete County, Utah, and Incorporated Areas'' addressed the flooding source South...

77 FR 50667 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-22

... table provided here represents the flooding sources, location of referenced elevations, effective and...). Specifically, it addresses the flooding sources Fourmile Creek and Lake Erie. DATES: Comments are to be... Jurisdictions)'' addressed the flooding sources Fourmile Creek and Lake Erie. That table contained inaccurate...

77 FR 55787 - Proposed Flood Elevation Determinations for the City of Carson City, NV

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-11

...-2011-0002; Internal Agency Docket No. FEMA-B-1233] Proposed Flood Elevation Determinations for the City of Carson City, NV AGENCY: Federal Emergency Management Agency, DHS. ACTION: Proposed rule... concerning proposed flood elevation determinations for the City of Carson City, Nevada. DATES: This...

77 FR 66790 - Proposed Flood Elevation Determinations for Madison County, AL and Incorporated Areas

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-07

...-2011-0002; Internal Agency Docket No. FEMA-B-1189] Proposed Flood Elevation Determinations for Madison... concerning proposed flood elevation determinations for Madison County, Alabama and Incorporated Areas. DATES... Mitigation Administration, Federal Emergency Management Agency, 500 C Street SW., Washington, DC 20472, (202...

78 FR 78808 - Proposed Flood Elevation Determinations for Pierce County, Washington, and Incorporated Areas

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-27

... sources in Pierce County, Washington. On April 16, 2012, FEMA published a proposed rulemaking at 77 FR...-2013-0002; Internal Agency Docket No. FEMA-B-7748] Proposed Flood Elevation Determinations for Pierce... proposed rule concerning proposed flood elevation determinations for Pierce County, Washington, and...

78 FR 22221 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-15

... table provided here represents the flooding sources, location of referenced elevations, effective and.... Specifically, it addresses the following flooding sources: Pea Branch and Reedy Branch. DATES: Comments are to... Areas'' did not address the flooding sources Pea Branch and Reedy Branch. That table omitted information...

77 FR 51745 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-27

.... Specifically, it addresses the following flooding sources: Back Creek, Big Elk Creek, Bohemia River, Chesapeake... Areas'' addressed the following flooding sources: Back Creek, Big Elk Creek, Bohemia River, Chesapeake... modified elevation in feet, and/or communities affected for the following flooding sources: Big Elk Creek...

44 CFR 65.12 - Revision of flood insurance rate maps to reflect base flood elevations caused by proposed...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Revision of flood insurance rate maps to reflect base flood elevations caused by proposed encroachments. 65.12 Section 65.12... INSURANCE AND HAZARD MITIGATION National Flood Insurance Program IDENTIFICATION AND MAPPING OF SPECIAL...

Analysis of floods, including the tropical storm Irene inundation, of the Ottauquechee River in Woodstock, Bridgewater, and Killington and of Reservoir Brook in Bridgewater and Plymouth, Vermont

USGS Publications Warehouse

Flynn, Robert H.

2014-01-01

In addition to the two digital flood inundation maps, flood profiles were created that depict the study reach flood elevation of tropical storm Irene of August 2011 and the 10-, 2-, 1-, and 0.2-percent AEP floods, also known as the 10-, 50-, 100-, and 500-year floods, respectively. The 10-, 2-, 1-, and 0.2-percent AEP flood discharges were determined using annual peak flow data from the USGS Ottauquechee River near West Bridgewater, Vt. streamgage (station 01150900). Flood profiles were computed for the Ottauquechee River and Reservoir Brook by means of a one-dimensional step-backwater model. The model was calibrated using documented high-water marks of the peak of the tropical storm Irene flood of August 2011 as well as stage discharge data as determined for USGS Ottauquechee River near West Bridgewater, Vt. streamgage (station 01150900). The simulated water-surface profiles were combined with a digital elevation model within a geographic information system to delineate the areas flooded during tropical storm Irene and for the 1-percent AEP water-surface profile. The digital elevation model data were derived from light detection and ranging (lidar) data obtained for a 3,281-foot (1,000-meter) corridor along the Ottauquechee River study reach and were augmented with 33-foot (10- meter) contour interval data in the modeled flood-inundation areas outside the lidar corridor. The 33-foot (10-meter) contour interval USGS 15-minute quadrangle topographic digital raster graphics map used to augment lidar data was produced at a scale of 1:24,000. The digital flood inundation maps and flood profiles along with information regarding current stage from USGS streamgages on the Internet provide emergency management personnel and residents with information that is critical for flood response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.

75 FR 18070 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... new scientific or technical data. The modifications are made pursuant to section 201 of the Flood...

75 FR 18073 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... new scientific or technical data. The modifications are made pursuant to section 201 of the Flood...

75 FR 81887 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-29

...Modified Base (1% annual-chance) Flood Elevations (BFEs) are finalized for the communities listed below. These modified BFEs will be used to calculate flood insurance premium rates for new buildings and their contents.

Dam-breach analysis and flood-inundation mapping for Lakes Ellsworth and Lawtonka near Lawton, Oklahoma

USGS Publications Warehouse

Rendon, Samuel H.; Ashworth, Chad E.; Smith, S. Jerrod

2012-01-01

Dams provide beneficial functions such as flood control, recreation, and reliable water supplies, but they also entail risk: dam breaches and resultant floods can cause substantial property damage and loss of life. The State of Oklahoma requires each owner of a high-hazard dam, which the Federal Emergency Management Agency defines as dams for which failure or misoperation probably will cause loss of human life, to develop an emergency action plan specific to that dam. Components of an emergency action plan are to simulate a flood resulting from a possible dam breach and map the resulting downstream flood-inundation areas. The resulting flood-inundation maps can provide valuable information to city officials, emergency managers, and local residents for planning the emergency response if a dam breach occurs. Accurate topographic data are vital for developing flood-inundation maps. This report presents results of a cooperative study by the city of Lawton, Oklahoma, and the U.S. Geological Survey (USGS) to model dam-breach scenarios at Lakes Ellsworth and Lawtonka near Lawton and to map the potential flood-inundation areas of such dam breaches. To assist the city of Lawton with completion of the emergency action plans for Lakes Ellsworth and Lawtonka Dams, the USGS collected light detection and ranging (lidar) data that were used to develop a high-resolution digital elevation model and a 1-foot contour elevation map for the flood plains downstream from Lakes Ellsworth and Lawtonka. This digital elevation model and field measurements, streamflow-gaging station data (USGS streamflow-gaging station 07311000, East Cache Creek near Walters, Okla.), and hydraulic values were used as inputs for the dynamic (unsteady-flow) model, Hydrologic Engineering Center's River Analysis System (HEC-RAS). The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum flood scenario and a sunny-day dam-breach scenario, as well as for maximum flood-inundation elevations and flood-wave arrival times for selected bridge crossings. Some areas of concern near the city of Lawton, if a dam breach occurs at Lakes Ellsworth or Lawtonka, include water treatment plants, wastewater treatment plants, recreational areas, and community-services offices.

Simulated and observed 2010 floodwater elevations in the Pawcatuck and Wood Rivers, Rhode Island

USGS Publications Warehouse

Zarriello, Phillip J.; Straub, David E.; Smith, Thor E.

2014-01-01

Heavy, persistent rains from late February through March 2010 caused severe flooding that set, or nearly set, peaks of record for streamflows and water levels at many long-term U.S. Geological Survey streamgages in Rhode Island. In response to this flood, hydraulic models of Pawcatuck River (26.9 miles) and Wood River (11.6 miles) were updated from the most recent approved U.S. Department of Homeland Security-Federal Emergency Management Agency flood insurance study (FIS) to simulate water-surface elevations (WSEs) for specified flows and boundary conditions. The hydraulic models were updated to Hydrologic Engineering Center-River Analysis System (HEC-RAS) using steady-state simulations and incorporate new field-survey data at structures, high resolution land-surface elevation data, and updated flood flows from a related study. The models were used to simulate the 0.2-percent annual exceedance probability (AEP) flood, which is the AEP determined for the 2010 flood in the Pawcatuck and Wood Rivers. The simulated WSEs were compared to high-water mark (HWM) elevation data obtained in a related study following the March–April 2010 flood, which included 39 HWMs along the Pawcatuck River and 11 HWMs along the Wood River. The 2010 peak flow generally was larger than the 0.2-percent AEP flow, which, in part, resulted in the FIS and updated model WSEs to be lower than the 2010 HWMs. The 2010 HWMs for the Pawcatuck River averaged about 1.6 feet (ft) higher than the 0.2-percent AEP WSEs simulated in the updated model and 2.5 ft higher than the WSEs in the FIS. The 2010 HWMs for the Wood River averaged about 1.3 ft higher than the WSEs simulated in the updated model and 2.5 ft higher than the WSEs in the FIS. The improved agreement of the updated simulated water elevations to observed 2010 HWMs provides a measure of the hydraulic model performance, which indicates the updated models better represent flooding at other AEPs than the existing FIS models.

A Study of Flood Evacuation Center Using GIS and Remote Sensing Technique

NASA Astrophysics Data System (ADS)

Mustaffa, A. A.; Rosli, M. F.; Abustan, M. S.; Adib, R.; Rosli, M. I.; Masiri, K.; Saifullizan, B.

2016-07-01

This research demonstrated the use of Remote Sensing technique and GIS to determine the suitability of an evacuation center. This study was conducted in Batu Pahat areas that always hit by a series of flood. The data of Digital Elevation Model (DEM) was obtained by ASTER database that has been used to delineate extract contour line and elevation. Landsat 8 image was used for classification purposes such as land use map. Remote Sensing incorporate with GIS techniques was used to determined the suitability location of the evacuation center from contour map of flood affected areas in Batu Pahat. GIS will calculate the elevation of the area and information about the country of the area, the road access and percentage of the affected area. The flood affected area map may provide the suitability of the flood evacuation center during the several levels of flood. The suitability of evacuation centers can be determined based on several criteria and the existing data of the evacuation center will be analysed. From the analysis among 16 evacuation center listed, there are only 8 evacuation center suitable for the usage during emergency situation. The suitability analysis was based on the location and the road access of the evacuation center toward the flood affected area. There are 10 new locations with suitable criteria of evacuation center proposed on the study area to facilitate the process of rescue and evacuating flood victims to much safer and suitable locations. The results of this study will help in decision making processes and indirectly will help organization such as fire-fighter and the Department of Social Welfare in their work. Thus, this study can contribute more towards the society.

Flood boundaries and water-surface profile for the computed 100-year flood, Swift Creek at Afton, Wyoming, 1986

USGS Publications Warehouse

Rankl, James G.; Wallace, Joe C.

1989-01-01

Flood flows on Swift Creek near Afton, Wyoming, were analyzed. Peak discharge with an average recurrence interval of 100 years was computed and used to determine the flood boundaries and water surface profile in the study reach. The study was done in cooperation with Lincoln County and the Town of Afton to determine the extent of flooding in the Town of Afton from a 100-year flood on Swift Creek. The reach of Swift Creek considered in the analysis extends upstream from the culvert at Allred County Road No. 12-135 to the US Geological Survey streamflow-gaging station located in the Bridger National Forest , a distance of 3.2 miles. Boundaries of the 100-year flood are delineated on a map using the computed elevation of the flood at each cross section, survey data, and a 1983 aerial photograph. The computed water surface elevation for the 100-year flood was plotted at each cross section, then the lateral extent of the flood was transferred to the flood map. Boundaries between cross sections were sketched using information taken from the aerial photograph. Areas that are inundated, but not part of the active flow, are designated on the cross sections. (Lantz-PTT)

Effects of anthropogenic land-subsidence on river flood hazard: a case study in Ravenna, Italy

NASA Astrophysics Data System (ADS)

Carisi, Francesca; Domeneghetti, Alessio; Castellarin, Attilio

2015-04-01

Can differential land-subsidence significantly alter the river flooding dynamics, and thus flood risk in flood prone areas? Many studies show how the lowering of the coastal areas is closely related to an increase in the flood-hazard due to more important tidal flooding and see level rise. On the contrary, the literature on the relationship between differential land-subsidence and possible alterations to riverine flood-hazard of inland areas is still sparse, while several areas characterized by significant land-subsidence rates during the second half of the 20th century experienced an intensification in both inundation magnitude and frequency. This study investigates the possible impact of a significant differential ground lowering on flood hazard in proximity of Ravenna, which is one of the oldest Italian cities, former capital of the Western Roman Empire, located a few kilometers from the Adriatic coast and about 60 km south of the Po River delta. The rate of land-subsidence in the area, naturally in the order of a few mm/year, dramatically increased up to 110 mm/year after World War II, primarily due to groundwater pumping and a number of deep onshore and offshore gas production platforms. The subsidence caused in the last century a cumulative drop larger than 1.5 m in the historical center of the city. Starting from these evidences and taking advantage of a recent digital elevation model of 10m resolution, we reconstructed the ground elevation in 1897 for an area of about 65 km2 around the city of Ravenna. We referred to these two digital elevation models (i.e. current topography and topographic reconstruction) and a 2D finite-element numerical model for the simulation of the inundation dynamics associated with several levee failure scenarios along embankment system of the river Montone. For each scenario and digital elevation model, the flood hazard is quantified in terms of water depth, speed and dynamics of the flooding front. The comparison enabled us to quantify alterations to the flooding hazard due to large and rapid differential land-subsidence, shedding some light on whether to consider anthropogenic land-subsidence among the relevant human-induced drivers of flood-risk change.

44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the SFHA are “reasonably safe from flooding”, and that they have on file, available upon request by... are “reasonably safe from flooding,” we will process a revision to the SFHA using the criteria set... from flooding.” (6) Data to substantiate the base flood elevation. If we complete a Flood Insurance...

44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the SFHA are “reasonably safe from flooding”, and that they have on file, available upon request by... are “reasonably safe from flooding,” we will process a revision to the SFHA using the criteria set... from flooding.” (6) Data to substantiate the base flood elevation. If we complete a Flood Insurance...

Evaluation of the U.S. Geological Survey standard elevation products in a two-dimensional hydraulic modeling application for a low relief coastal floodplain

USGS Publications Warehouse

Witt, Emitt C.

2015-01-01

Growing use of two-dimensional (2-D) hydraulic models has created a need for high resolution data to support flood volume estimates, floodplain specific engineering data, and accurate flood inundation scenarios. Elevation data are a critical input to these models that guide the flood-wave across the landscape allowing the computation of valuable engineering specific data that provides a better understanding of flooding impacts on structures, debris movement, bed scour, and direction. High resolution elevation data are becoming publicly available that can benefit the 2-D flood modeling community. Comparison of these newly available data with legacy data suggests that better modeling outcomes are achieved by using 3D Elevation Program (3DEP) lidar point data and the derived 1 m Digital Elevation Model (DEM) product relative to the legacy 3 m, 10 m, or 30 m products currently available in the U.S. Geological Survey (USGS) National Elevation Dataset. Within the low topographic relief of a coastal floodplain, the newer 3DEP data better resolved elevations within the forested and swampy areas achieving simulations that compared well with a historic flooding event. Results show that the 1 m DEM derived from 3DEP lidar source provides a more conservative estimate of specific energy, static pressure, and impact pressure for grid elements at maximum flow relative to the legacy DEM data. Better flood simulations are critically important in coastal floodplains where climate change driven storm frequency and sea level rise will contribute to more frequent flooding events.

Repeated multibeam echosounder hydrographic surveys of 15 selected bridge crossings along the Missouri River from Niobrara to Rulo, Nebraska, during the flood of 2011

USGS Publications Warehouse

Dietsch, Benjamin J.; Densmore, Brenda K.; Strauch, Kellan R.

2014-01-01

In 2011, unprecedented flooding in the Missouri River prompted transportation agencies to increase the frequency of monitoring riverbed elevations near bridges that cross the Missouri River. Hydrographic surveys were completed in cooperation with the Nebraska Department of Roads, using a multibeam echosounder at 15 highway bridges spanning the Missouri River from Niobrara to Rulo, Nebraska during and after the extreme 2011 flood. Evidence of bed elevation change near bridge piers was documented. The greatest amount of bed elevation change during the 2011 flood documented for this study occurred at the Burt County Missouri River Bridge at Decatur, Nebraska, where scour of about 45 feet, from before flooding, occurred between a bridge abutment and pier. Of the remaining sites, highway bridges where bed elevation change near piers appeared to have exceeded 10 feet include the Abraham Lincoln Memorial Bridge at Blair, Nebr., Bellevue Bridge at Bellevue, Nebr., and Nebraska City Bridge at Nebraska City, Nebr. Hydrographic surveys at 14 of the 15 sites were completed in mid-July and again in early October or late-November 2011. Near three of the bridges, the bed elevation of locations surveyed in July increased by more than 10 feet, on average, by late October or early November 2011. Bed elevations increased between 1 and 10 feet, on average, near six bridges. Near the remaining four bridges, bed elevations decreased between 1 and 4 feet, on average, from July to late October or early November.

Flood of June 26-29, 2006, Mohawk, Delaware, and Susquehanna River Basins, New York

USGS Publications Warehouse

Suro, Thomas P.; Firda, Gary D.; Szabo, Carolyn O.

2009-01-01

A stalled frontal system caused tropical moisture to be funneled northward into New York, causing severe flooding in the Mohawk, Delaware, and Susquehanna River basins during June 26-29, 2006. Rainfall totals for this multi-day event ranged from 2 to 3 inches to greater than 13 inches in southern New York. The storm and flooding claimed four lives in New York, destroyed or damaged thousands of homes and businesses, and closed hundreds of roads and highways. Thousands of people evacuated their homes as floodwaters reached new record elevations at many locations within the three basins. Twelve New York counties were declared Federal disaster areas, more than 15,500 residents applied for disaster assistance, and millions of dollars in damages resulted from the flooding. Disaster-recovery assistance for individuals and businesses adversely affected by the floods of June 2006 reached more than $227 million. The National Weather Service rainfall station at Slide Mountain recorded storm totals of more than 8 inches of rainfall, and the stations at Walton and Fishs Eddy, NY, recorded storm totals of greater than 13 inches of rainfall. The U.S. Geological Survey (USGS) stream-gaging stations at Mohawk River at Little Falls, West Branch Delaware River at Hale Eddy, and Susquehanna River at Vestal, NY, among others, recorded peak discharges of 35,000 ft3/s, 43,400 ft3/s, and 119,000 ft3/s respectively, with greater than 100-year recurrence intervals. The peak water-surface elevation 21.47 ft and the peak discharge 189,000 ft3/s recorded on June 28, 2006, at the Delaware River at Port Jervis stream-gaging station were the highest recorded since the flood of August 1955. At the Susquehanna River at Conklin, NY, stream-gaging station, which has been in operation since 1912, the peak water-surface elevation 25.02 ft and peak discharge 76,800 ft3/s recorded on June 28, 2006, exceeded the previous period-of-record maximums that were set during the flood of March 1936. Documented peak water-surface elevations during the June 2006 flood at many study sites in the Mohawk, Delaware, and Susquehanna River basins exceeded the 100-year flood-profile elevations determined in the flood-insurance studies prepared by the Federal Emergency Management Agency.

10. VIEW OF THE SOUTH ELEVATION AND THE FLOOD GATE ...

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

10. VIEW OF THE SOUTH ELEVATION AND THE FLOOD GATE ON THE PRESSURE CULVERT, LOOKING NORTH. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

Sea-Level Rise and Flood Potential along the California Coast

NASA Astrophysics Data System (ADS)

Delepine, Q.; Leung, C.

2013-12-01

Sea-level rise is becoming an ever-increasing problem in California. Sea-level is expected to rise significantly in the next 100 years, which will raise flood elevations in coastal communities. This will be an issue for private homeowners, businesses, and the state. One study suggests that Venice Beach could lose a total of at least $440 million in tourism spending and tax dollars from flooding and beach erosion if sea level rises 1.4 m by 2100. In addition, several airports, such as San Francisco International Airport, are located in coastal regions that have flooded in the past and will likely be flooded again in the next 30 years, but sea-level rise is expected to worsen the effects of flooding in the coming decades It is vital for coastal communities to understand the risks associated with sea-level rise so that they can plan to adapt to it. By obtaining accurate LiDAR elevation data from the NOAA Digital Coast Website (http://csc.noaa.gov/dataviewer/?keyword=lidar#), we can create flood maps to simulate sea level rise and flooding. The data are uploaded to ArcGIS and contour lines are added for different elevations that represent future coastlines during 100-year flooding. The following variables are used to create the maps: 1. High-resolution land surface elevation data - obtained from NOAA 2. Local mean high water level - from USGS 3. Local 100-year flood water level - from the Pacific Institute 4. Sea-level rise projections for different future dates (2030, 2050, and 2100) - from the National Research Council The values from the last three categories are added to represent sea-level rise plus 100-year flooding. These values are used to make the contour lines that represent the projected flood elevations, which are then exported as KML files, which can be opened in Google Earth. Once these KML files are made available to the public, coastal communities will gain an improved understanding of how flooding and sea-level rise might affect them in the future. This would allow them to plan ahead to reduce the level of risk to homes, industry, and infrastructure San Francisco International Airport will be most likely be flooded in the next 30 years. Blue lines indicate current Mean High Water Levels. Yellow lines indicate the Mean High Water level combined with flood levels for 2030. Green, 2050, and Red lines, 2100

The 1965 Mississippi River flood in Iowa

USGS Publications Warehouse

Schwob, Harlan H.; Myers, Richard E.

1965-01-01

Flood data compiled for the part of the River along the eastern border include flood discharges, flood elevations, and the frequency of floods of varying magnitudes. They also include the daily or more frequent stage and discharge data for both the Mississippi River and the downstream gaging stations on Iowa tributaries for the period March-May 1965. Sufficient data are presented to permit studied for preparation of plans for protective works and plans for zoning or for flood plain regulation.

Water-surface elevations and channel characteristics for selected reaches of the Rogue River and Elk Creek, Jackson and Josephine Counties, Oregon

USGS Publications Warehouse

Harris, D.D.

1970-01-01

The central Rogue River valley, because of its mild climate, fertile soil, scenic attractions, and sport-fishery resource, has great potential for future population growth and industrial development. As the population grows and the area develops, zoning becomes necessary to assure the most beneficial use of the land, especially of the flood plains. To establish land-use zones on the flood plains, the area subject to inundation and elevation of floods must be considered. Areas flooded during the December 1964 flood and the approximate limits of the 1861 flood in Jackson and Josephine Counties are shown in two interim reports (Corps of Engineers, 1965); however, there are no published flood-elevation profiles to use as a basis for establishing meaningful land-use-zone boundaries or for delineating inundated areas of other floods.

Effects of flooding regime and seedling treatment on early survival and growth of nuttall oak

USGS Publications Warehouse

Burkett, V.R.; Draugelis-Dale, R.O.; Williams, H.M.; Schoenholtz, S.H.

2005-01-01

Effects of flooding on survival and growth of three different types of Nuttall oak (Quercus texana Buckl.) seedlings were observed at the end of third and fifth growing seasons at Yazoo National Wildlife Refuge, Mississippi, U.S.A. Three types of seedlings were planted in January 1995 in a split-plot design, with four replications at each of two elevations on floodprone, former cropland in Sharkey clay soil. The lower of the two planting elevations was inundated for 21 days during the first growing season, whereas the higher elevation did not flood during the 5-year period of this study. The three types of 1-0 seedlings were bareroot seedlings, seedlings grown in containers (3.8 ?? 21a??cm plastic seedling cones), and container-grown seedlings inoculated with vegetative mycelia of Pisolithus tinctorius (Pers.) Coker. Survival of all the three seedling types was greatest at the lower, intermittently flooded elevation, indicating that drought and related effects on plant competition were more limiting to seedling survival than flooding. At the lower elevation, survival of mycorrhizal-inoculated container seedlings was greater than that of noninoculated container seedlings. Survival among bareroot seedlings and inoculated container seedlings was not significantly different at either elevation. At the higher, nonflooded elevation, however, bareroot seedling survival was greater than the survival of container seedlings without inoculation. Differences were significant among the inoculated and the noninoculated container seedlings, with higher survival of inoculated seedlings at both elevations, though differences were only significant in year 3. At the end of the fifth year, height of bareroot seedlings was significantly greater than the heights of both types of container-grown seedlings at both planting elevations. Because seedlings grown in the plastic seedlings cones did not survive better than the bareroot seedlings at either planting elevation, the bareroot stock appear to be the economically superior choice for regeneration in Sharkey soil.

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.

Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio

USGS Publications Warehouse

Sherwood, James M.; Huitger, Carrie A.; Ebner, Andrew D.; Koltun, G.F.

2008-01-01

The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in selected undredged reaches; (4) estimate flood elevations for existing conditions in both undredged and previously dredged reaches; (5) evaluate the height of the levees required to contain floods with selected recurrence intervals in previously dredged reaches; and (6) estimate flood elevations for several hypothetical dredging and streambed aggradation scenarios in undredged reaches. The amount of barren land in the Wheeling Creek watershed has decreased from 20 to 1 percent of the basin area based on land-cover characteristics from 1979 and 2001. Barren lands appear to have been converted primarily to pasture, presumably as a result of surface-mine reclamation. Croplands also decreased from 13 to 8 percent of the basin area. The combined decrease in barren lands and croplands is approximately offset by the increase in pasture. Stream-channel surveys conducted in 1987 and again in 2006 at 21 sites in four previously dredged reaches of Wheeling Creek indicate little change in the elevation, slope, and geometry of the channel at most sites. The mean change in width-averaged bed and thalweg elevations for the 21 cross sections was 0.1 feet. Bankfull widths, mean depths, and cross-sectional areas measured at 12 sites in undredged reaches were compared to estimates determined from regional equations. The mean percentage difference between measured and estimated bankfull widths was -0.2 percent, suggesting that bankfull widths in the Wheeling Creek Basin are generally about the same as regional averages for undisturbed basins of identical drainage area. For bankfull mean depth and cross-sectional area, the mean percentage differences between the measured and estimated values were -16.0 and -11.2, respectively. The predominantly negative bias in differences between the measured and estimated values indicates that bankfull mean depths and cross-sectional areas in studied reaches generally are smaller than the regional trend. This may be an indication of channel filling and over widening or it may reflect insufficient representation in the regional dataset of basins with characteristics like that of Wheeling Creek. Step-backwater models were constructed for four previously dredged reaches to determine the height of levees required to contain floods with recurrence intervals of 2, 10, 50, and 100 years. Existing levees (all of which are uncertified) were found to contain the 100-year flood at only 20 percent of the surveyed cross sections. At the other 80 percent of the surveyed cross sections, levee heights would have to be raised an average of 2.5 feet and as much as 6.3 feet to contain the 100-year flood. Step-backwater models also were constructed for three undredged reaches to assess the impacts of selected dredging and streambed aggradation scenarios on water-surface elevations corresponding to the 2-, 10-, 50-, and 100-year floods. Those models demonstrated that changes in water-surface elevations associated with a given depth of dredging were proportionately smaller for larger floods due to the fact that more of the flood waters are outside of the main channel. For example, 2.0 feet of dredging in the three study reaches would lower the water-surface elevation an average of 1.30 feet for the 2-year flood and 0.64 feet for the 100-year flood.

Flood-hazard analysis of four headwater streams draining the Argonne National Laboratory property, DuPage County, Illinois

USGS Publications Warehouse

Soong, David T.; Murphy, Elizabeth A.; Straub, Timothy D.; Zeeb, Hannah L.

2016-11-22

Results of a flood-hazard analysis conducted by the U.S. Geological Survey, in cooperation with the Argonne National Laboratory, for four headwater streams within the Argonne National Laboratory property indicate that the 1-percent and 0.2-percent annual exceedance probability floods would cause multiple roads to be overtopped. Results indicate that most of the effects on the infrastructure would be from flooding of Freund Brook. Flooding on the Northeast and Southeast Drainage Ways would be limited to overtopping of one road crossing for each of those streams. The Northwest Drainage Way would be the least affected with flooding expected to occur in open grass or forested areas.The Argonne Site Sustainability Plan outlined the development of hydrologic and hydraulic models and the creation of flood-plain maps of the existing site conditions as a first step in addressing resiliency to possible climate change impacts as required by Executive Order 13653 “Preparing the United States for the Impacts of Climate Change.” The Hydrological Simulation Program-FORTRAN is the hydrologic model used in the study, and the Hydrologic Engineering Center‒River Analysis System (HEC–RAS) is the hydraulic model. The model results were verified by comparing simulated water-surface elevations to observed water-surface elevations measured at a network of five crest-stage gages on the four study streams. The comparison between crest-stage gage and simulated elevations resulted in an average absolute difference of 0.06 feet and a maximum difference of 0.19 feet.In addition to the flood-hazard model development and mapping, a qualitative stream assessment was conducted to evaluate stream channel and substrate conditions in the study reaches. This information can be used to evaluate erosion potential.

75 FR 35672 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-23

...This interim rule lists communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the modified BFEs for new buildings and their contents.

Towards the optimal fusion of high-resolution Digital Elevation Models for detailed urban flood assessment

NASA Astrophysics Data System (ADS)

Leitão, J. P.; de Sousa, L. M.

2018-06-01

Newly available, more detailed and accurate elevation data sets, such as Digital Elevation Models (DEMs) generated on the basis of imagery from terrestrial LiDAR (Light Detection and Ranging) systems or Unmanned Aerial Vehicles (UAVs), can be used to improve flood-model input data and consequently increase the accuracy of the flood modelling results. This paper presents the first application of the MBlend merging method and assesses the impact of combining different DEMs on flood modelling results. It was demonstrated that different raster merging methods can have different and substantial impacts on these results. In addition to the influence associated with the method used to merge the original DEMs, the magnitude of the impact also depends on (i) the systematic horizontal and vertical differences of the DEMs, and (ii) the orientation between the DEM boundary and the terrain slope. The greater water depth and flow velocity differences between the flood modelling results obtained using the reference DEM and the merged DEMs ranged from -9.845 to 0.002 m, and from 0.003 to 0.024 m s-1 respectively; these differences can have a significant impact on flood hazard estimates. In most of the cases investigated in this study, the differences from the reference DEM results were smaller for the MBlend method than for the results of the two conventional methods. This study highlighted the importance of DEM merging when conducting flood modelling and provided hints on the best DEM merging methods to use.

Statistical Development of Flood Frequency and Magnitude Equations for the Cosumnes and Mokelumne River Drainage Basins, Sierra Nevada, California

NASA Astrophysics Data System (ADS)

Burns, R. G.; Meyer, R. W.; Cornwell, K.

2003-12-01

In-basin statistical relations allow for development of regional flood frequency and magnitude equations in the Cosumnes River and Mokelumne River drainage basins. Current equations were derived from data collected through 1975, and do not reflect newer data with some significant flooding. Physical basin characteristics (area, mean basin elevation, slope of longest reach, and mean annual precipitation) were correlated against predicted flood discharges for each of the 5, 10, 25, 50, 100, 200, and 500-year recurrence intervals in a multivariate analysis. Predicted maximum instantaneous flood discharges were determined using the PEAKFQ program with default settings, for 24 stream gages within the study area presumed not affected by flow management practices. For numerical comparisons, GIS-based methods using Spatial Analyst and the Arc Hydro Tools extension were applied to derive physical basin characteristics as predictor variables from a 30m digital elevation model (DEM) and a mean annual precipitation raster (PRISM). In a bivariate analysis, examination of Pearson correlation coefficients, F-statistic, and t & p thresholds show good correlation between area and flood discharges. Similar analyses show poor correlation for mean basin elevation, slope and precipitation, with flood discharge. Bivariate analysis suggests slope may not be an appropriate predictor term for use in the multivariate analysis. Precipitation and elevation correlate very well, demonstrating possible orographic effects. From the multivariate analysis, less than 6% of the variability in the correlation is not explained for flood recurrences up to 25 years. Longer term predictions up to 500 years accrue greater uncertainty with as much as 15% of the variability in the correlation left unexplained.

Real Time Monitoring of Flooding from Microwave Satellite Observations

NASA Technical Reports Server (NTRS)

Galantowicz, John F.; Frey, Herb (Technical Monitor)

2002-01-01

We have developed a new method for making high-resolution flood extent maps (e.g., at the 30-100 m scale of digital elevation models) in real-time from low-resolution (20-70 km) passive microwave observations. The method builds a "flood-potential" database from elevations and historic flood imagery and uses it to create a flood-extent map consistent with the observed open water fraction. Microwave radiometric measurements are useful for flood monitoring because they sense surface water in clear-or-cloudy conditions and can provide more timely data (e.g., compared to radars) from relatively wide swath widths and an increasing number of available platforms (DMSP, ADEOS-II, Terra, NPOESS, GPM). The chief disadvantages for flood mapping are the radiometers' low resolution and the need for local calibration of the relationship between radiances and open-water fraction. We present our method for transforming microwave sensor-scale open water fraction estimates into high-resolution flood extent maps and describe 30-day flood map sequences generated during a retrospective study of the 1993 Great Midwest Flood. We discuss the method's potential improvement through as yet unimplemented algorithm enhancements and expected advancements in microwave radiometry (e.g., improved resolution and atmospheric correction).

77 FR 18766 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1114] Proposed Flood Elevation Determinations Correction... locations above. Please refer to the revised Flood Insurance Rate Map located at the community map...

76 FR 43968 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-22

... qualify or remain qualified for participation in the National Flood Insurance Program (NFIP). In addition, these elevations, once finalized, will be used by insurance agents and others to calculate appropriate flood insurance premium rates for new buildings and the contents in those buildings. DATES: Comments are...

44 CFR 67.11 - Notice of final determination.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.11 Notice of final determination. The Federal Insurance Administrator's notice of the final flood elevation determination for a community shall be in written form and...

44 CFR 67.7 - Collection of appeal data.

Code of Federal Regulations, 2014 CFR

2014-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.7 Collection of appeal data. (a) Appeals by private persons to... Federal Insurance Administrator's proposed flood elevation determination to the CEO or to such agency as...

44 CFR 67.11 - Notice of final determination.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.11 Notice of final determination. The Federal Insurance Administrator's notice of the final flood elevation determination for a community shall be in written form and...

44 CFR 67.7 - Collection of appeal data.

Code of Federal Regulations, 2012 CFR

2012-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.7 Collection of appeal data. (a) Appeals by private persons to... Federal Insurance Administrator's proposed flood elevation determination to the CEO or to such agency as...

Digital floodplain mapping and an analysis of errors involved

USGS Publications Warehouse

Hamblen, C.S.; Soong, D.T.; Cai, X.

2007-01-01

Mapping floodplain boundaries using geographical information system (GIS) and digital elevation models (DEMs) was completed in a recent study. However convenient this method may appear at first, the resulting maps potentially can have unaccounted errors. Mapping the floodplain using GIS is faster than mapping manually, and digital mapping is expected to be more common in the future. When mapping is done manually, the experience and judgment of the engineer or geographer completing the mapping and the contour resolution of the surface topography are critical in determining the flood-plain and floodway boundaries between cross sections. When mapping is done digitally, discrepancies can result from the use of the computing algorithm and digital topographic datasets. Understanding the possible sources of error and how the error accumulates through these processes is necessary for the validation of automated digital mapping. This study will evaluate the procedure of floodplain mapping using GIS and a 3 m by 3 m resolution DEM with a focus on the accumulated errors involved in the process. Within the GIS environment of this mapping method, the procedural steps of most interest, initially, include: (1) the accurate spatial representation of the stream centerline and cross sections, (2) properly using a triangulated irregular network (TIN) model for the flood elevations of the studied cross sections, the interpolated elevations between them and the extrapolated flood elevations beyond the cross sections, and (3) the comparison of the flood elevation TIN with the ground elevation DEM, from which the appropriate inundation boundaries are delineated. The study area involved is of relatively low topographic relief; thereby, making it representative of common suburban development and a prime setting for the need of accurately mapped floodplains. This paper emphasizes the impacts of integrating supplemental digital terrain data between cross sections on floodplain delineation. ?? 2007 ASCE.

Dam-breach analysis and flood-inundation mapping for selected dams in Oklahoma City, Oklahoma, and near Atoka, Oklahoma

USGS Publications Warehouse

Shivers, Molly J.; Smith, S. Jerrod; Grout, Trevor S.; Lewis, Jason M.

2015-01-01

Digital-elevation models, field survey measurements, hydraulic data, and hydrologic data (U.S. Geological Survey streamflow-gaging stations North Canadian River below Lake Overholser near Oklahoma City, Okla. [07241000], and North Canadian River at Britton Road at Oklahoma City, Okla. [07241520]), were used as inputs for the one-dimensional dynamic (unsteady-flow) models using Hydrologic Engineering Centers River Analysis System (HEC–RAS) software. The modeled flood elevations were exported to a geographic information system to produce flood-inundation maps. Water-surface profiles were developed for a 75-percent probable maximum flood dam-breach scenario and a sunny-day dam-breach scenario, as well as for maximum flood-inundation elevations and flood-wave arrival times at selected bridge crossings. Points of interest such as community-services offices, recreational areas, water-treatment plants, and wastewater-treatment plants were identified on the flood-inundation maps.

Modeling Flood Plain Hydrology and Forest Productivity of Congaree Swamp, South Carolina

USGS Publications Warehouse

Doyle, Thomas W.

2009-01-01

An ecological field and modeling study was conducted to examine the flood relations of backswamp forests and park trails of the flood plain portion of Congaree National Park, S.C. Continuous water level gages were distributed across the length and width of the flood plain portion - referred to as 'Congaree Swamp' - to facilitate understanding of the lag and peak flood coupling with stage of the Congaree River. A severe and prolonged drought at study start in 2001 extended into late 2002 before backswamp zones circulated floodwaters. Water levels were monitored at 10 gaging stations over a 4-year period from 2002 to 2006. Historical water level stage and discharge data from the Congaree River were digitized from published sources and U.S. Geological Survey (USGS) archives to obtain long-term daily averages for an upstream gage at Columbia, S.C., dating back to 1892. Elevation of ground surface was surveyed for all park trails, water level gages, and additional circuits of roads and boundaries. Rectified elevation data were interpolated into a digital elevation model of the park trail system. Regression models were applied to establish time lags and stage relations between gages at Columbia, S.C., and gages in the upper, middle, and lower reaches of the river and backswamp within the park. Flood relations among backswamp gages exhibited different retention and recession behavior between flood plain reaches with greater hydroperiod in the lower reach than those in the upper and middle reaches of the Congaree Swamp. A flood plain inundation model was developed from gage relations to predict critical river stages and potential inundation of hiking trails on a real-time basis and to forecast the 24-hour flood In addition, tree-ring analysis was used to evaluate the effects of flood events and flooding history on forest resources at Congaree National Park. Tree cores were collected from populations of loblolly pine (Pinus taeda), baldcypress (Taxodium distichum), water tupelo (Nyssa aquatica), green ash (Fraxinus pennslyvanica), laurel oak (Quercus laurifolia), swamp chestnut oak (Quercus michauxii), and sycamore (Plantanus occidentalis) within Congaree Swamp in highand low-elevation sites characteristic of shorter and longer flood duration and related to upriver flood controls and dam operation. Ring counts and dating indicated that all loblolly pine trees and nearly all baldcypress collections in this study are postsettlement recruits and old-growth cohorts, dating from 100 to 300 years in age. Most hardwood species and trees cored for age analysis were less than 100 years old, demonstrating robust growth and high site quality. Growth chronologies of loblolly pine and baldcypress exhibited positive and negative inflections over the last century that corresponded with climate history and residual effects of Hurricane Hugo in 1989. Stemwood production on average was less for trees and species on sites with longer flood retention and hydroperiod affected more by groundwater seepage and site elevation than river floods. Water level data provided evidence that stream regulation and operations of the Saluda Dam (post-1934) have actually increased the average daily water stage in the Congaree River. There was no difference in tree growth response by species or hydrogeomorphic setting to predam and postdam flood conditions and river stage. Climate-growth analysis showed that long-term growth variation is controlled more by spring/ summer temperatures in loblolly pine and by spring/summer precipitation in baldcypress than flooding history.

Development of a hydraulic model and flood-inundation maps for the Wabash River near the Interstate 64 Bridge near Grayville, Illinois

USGS Publications Warehouse

Boldt, Justin A.

2018-01-16

A two-dimensional hydraulic model and digital flood‑inundation maps were developed for a 30-mile reach of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois. The flood-inundation maps, which can be accessed through the U.S. Geological Survey (USGS) Flood Inundation Mapping Science web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Wabash River at Mount Carmel, Ill (USGS station number 03377500). Near-real-time stages at this streamgage may be obtained on the internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service (NWS) Advanced Hydrologic Prediction Service (AHPS) at http://water.weather.gov/ahps/, which also forecasts flood hydrographs at this site (NWS AHPS site MCRI2). The NWS AHPS forecasts peak stage information that may be used with the maps developed in this study to show predicted areas of flood inundation.Flood elevations were computed for the Wabash River reach by means of a two-dimensional, finite-volume numerical modeling application for river hydraulics. The hydraulic model was calibrated by using global positioning system measurements of water-surface elevation and the current stage-discharge relation at both USGS streamgage 03377500, Wabash River at Mount Carmel, Ill., and USGS streamgage 03378500, Wabash River at New Harmony, Indiana. The calibrated hydraulic model was then used to compute 27 water-surface elevations for flood stages at 1-foot (ft) intervals referenced to the streamgage datum and ranging from less than the action stage (9 ft) to the highest stage (35 ft) of the current stage-discharge rating curve. The simulated water‑surface elevations were then combined with a geographic information system digital elevation model, derived from light detection and ranging data, to delineate the area flooded at each water level.The availability of these maps, along with information on the internet regarding current stage from the USGS streamgage at Mount Carmel, Ill., and forecasted stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood-response activities such as evacuations and road closures, as well as for postflood recovery efforts.

77 FR 30220 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

... proof Flood Insurance Study and FIRM available at the address cited below for each community. The BFEs... Areas of 175. Kaufman County. Approximately 1 mile +342 downstream of State Highway 274. Duck Creek...

76 FR 3531 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

... proof Flood Insurance Study and FIRM available at the address cited below for each community. The BFEs... (All Jurisdictions) Docket No.: FEMA-B-1085 Duck Lake Entire shoreline within +930 Township of Clarence...

75 FR 62057 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-07

... buildings. Comments on any aspect of the Flood Insurance Study and FIRM, other than the proposed BFEs, will... State Highway 274. Duck Creek Approximately 925 feet None +458 Unincorporated Areas of downstream of...

75 FR 67317 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-02

... buildings. Comments on any aspect of the Flood Insurance Study and FIRM, other than the proposed BFEs, will... Approximately 700 feet None +41 City of Brooksville, downstream of Duck Unincorporated Areas Pond Road (at...

Magnitude and extent of flooding at selected river reaches in western Washington, January 2009

USGS Publications Warehouse

Mastin, M.C.; Gendaszek, A.S.; Barnas, C.R.

2010-01-01

A narrow plume of warm, moist tropical air produced prolonged precipitation and melted snow in low-to-mid elevations throughout western Washington in January 2009. As a result, peak-of-record discharges occurred at many long-term streamflow-gaging stations in the region. A disaster was declared by the President for eight counties in Washington State and by May 2009, aid payments by the Federal Emergency Management Agency (FEMA) had exceeded $17 million. In an effort to document the flood and to obtain flood information that could be compared with simulated flood extents that are commonly prepared in conjunction with flood insurance studies by FEMA, eight stream reaches totaling 32.6 miles were selected by FEMA for inundation mapping. The U.S. Geological Survey?s Washington Water Science Center used a survey-grade global positioning system (GPS) the following summer to survey high-water marks (HWMs) left by the January 2009 flood at these reaches. A Google Maps (copyright) application was developed to display all HWM data on an interactive mapping tool on the project?s web site soon after the data were collected. Water-surface profiles and maps that display the area and depth of inundation were produced through a geographic information system (GIS) analysis that combined surveyed HWM elevations with Light Detection and Ranging (LiDAR)-derived digital elevation models of the study reaches and surrounding terrain. In several of the reaches, floods were well confined in their flood plains and were relatively straightforward to map. More common, however, were reaches with more complicated hydraulic geometries where widespread flooding resulted in flows that separated from the main channel. These proved to be more difficult to map, required subjective hydrologic judgment, and relied on supplementary information, such as aerial photographs and descriptions of the flooding from local landowners and government officials to obtain the best estimates of the extent of flooding.

75 FR 78607 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-16

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... knowledge of changed conditions or new scientific or technical data. The modifications are made pursuant to...

Coastal flood of February 7, 1978, in Maine, Massachusetts, and New Hampshire

USGS Publications Warehouse

Gadoury, Russell A.

1979-01-01

This report contains data which document the flooding along parts of the New England coast. Elevations of 203 floodmarks in Massachusetts, 104 in Maine, and 46 in New Hampshire are given. Also included are some historical coastal flood data and a list of other storm-related studies. 

Comparison between flood prone areas' geomorphic features in the Abruzzo region

NASA Astrophysics Data System (ADS)

Orlando, D.; Giglioni, M.; Magnaldi, S.

2017-07-01

Flood risk maps are one of the main non-structural measures for risk mitigation, but, as the risk knowledge degree is directly proportional to the community interest and financial capability, many sites are devoid of flood inundation areas studies. Recently many authors have investigated the capability of flood prone areas individuation with geomorphological DIGITAL ELEVATION MODEL(DEM) based approaches. These approaches highlight the role of geomorphic features derived from DEM, in this case slope, curvature, elevation, and topographic wetness index, to preliminary inundated areas' identification, without using hydraulic simulations. The present studies aim to analyze the geomorphic features of different hazard levels that lie under the identified inundated areas that have been carried out by the Abruzzo Region Basin Authority. The Aterno-Pescara and Foro river basins have been investigated. The results show that the characteristics of the flooded areas can be clearly distinguished from those of the entire basin,however, the difficultly of geomorphic features in individuatingthe areas of different hazard classifications is obvious.

77 FR 44497 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

75 FR 82274 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-30

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

76 FR 77155 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-12

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

77 FR 20992 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-09

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

77 FR 30219 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

75 FR 82272 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-30

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

75 FR 82275 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-30

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

75 FR 18090 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... communities where modification of the Base (1% annual-chance) Flood Elevations (BFEs) is appropriate because of new scientific or technical data. New flood insurance premium rates will be calculated from the... conditions or new scientific or technical data. The modifications are made pursuant to section 201 of the...

Flood of April 2-4, 2005, Delaware River Main Stem from Port Jervis, New York, to Cinnaminson, New Jersey

USGS Publications Warehouse

Reed, Timothy J.; Protz, Amy R.

2007-01-01

Several conditions, including saturated soils, snowmelt, and heavy rains, caused flooding on the Delaware River on April 2-4, 2005. The event occurred 50 years after the historic 1955 Delaware River flood, and only six months after a smaller but equally notable flood on September 18-19, 2004. The Delaware River flooded for a third time in 22 months in June, 2006. The peak flows and elevations of the 2005 flood were similar to those on June 28-29, 2006. The following report describes the April 2-4, 2005, Delaware River flood, and includes the associated precipitation amounts, peak flows and elevations, and flood frequencies. A comparison of historic Delaware River floods also is presented. The appendix of the report contains detailed information for 156 high-water mark elevations obtained on the main stem of the Delaware River from Port Jervis, New York, to Cinnaminson, New Jersey, for the April 2-4, 2005 flood. The April 2005 event originated with frequent precipitation from December 2004 to March 2005 which saturated the soils in the upper Delaware River Basin. The cold winter froze some of the soils and left a snowpack at higher elevations equivalent to as much as 10 inches of water in some areas. Temperatures rose above freezing, and heavy rains averaging 1 to 3 inches on March 27, 2005, melted some of the snow, causing the Delaware River to rise; however, peak elevations were still 2 to 7 feet below flood stage. Another round of rainfall averaging 2-5 inches in the basin on April 2, 2005, melted the remaining snowpack. The combination of snowmelt and runoff from the two storms produced flood conditions along the main stem of the Delaware River. Flood frequencies of flows at selected tributaries to the Delaware River did not exceed the 35-year recurrence intervals. The Delaware River main stem peak-flow recurrence intervals ranged from 40 to 80 years; flows were approximately 20 percent less than those from the peak of record in 1955. Peak elevations exceeded National Weather Service flood stages defined at continuous-record streamflow-gaging stations by 5 to 7 feet, but were on average 3 to 5 feet lower than the peak of record in August 1955. Peak elevations determined at 48 sites along the main stem of the Delaware River defined the flood profile between the gaging stations. The peak elevation in the tide-effected portion of the Delaware (downstream of Trenton, New Jersey), occurred on April 2, 2 days before the riverine peak, as a result of water pushed into the bay by a low-pressure system situated just off the coast. Every county located along the main stem of the Delaware River was declared a Federal disaster area. Property damage estimates in Pennsylvania, New York, and New Jersey exceeded $200 million.

44 CFR 66.4 - Appointment of consultation coordination officer.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION... establish or to modify flood elevations pursuant to a new study or a restudy. When a CCO is appointed by the...

44 CFR 66.4 - Appointment of consultation coordination officer.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION... establish or to modify flood elevations pursuant to a new study or a restudy. When a CCO is appointed by the...

44 CFR 66.4 - Appointment of consultation coordination officer.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION... establish or to modify flood elevations pursuant to a new study or a restudy. When a CCO is appointed by the...

Simulated and observed 2010 floodwater elevations in selected river reaches in the Pawtuxet River Basin, Rhode Island

USGS Publications Warehouse

Zarriello, Phillip J.; Olson, Scott A.; Flynn, Robert H.; Strauch, Kellan R.; Murphy, Elizabeth A.

2014-01-01

Heavy, persistent rains from late February through March 2010 caused severe flooding that set, or nearly set, peaks of record for streamflows and water levels at many long-term streamgages in Rhode Island. In response to this event, hydraulic models were updated for selected reaches covering about 56 river miles in the Pawtuxet River Basin to simulate water-surface elevations (WSEs) at specified flows and boundary conditions. Reaches modeled included the main stem of the Pawtuxet River, the North and South Branches of the Pawtuxet River, Pocasset River, Simmons Brook, Dry Brook, Meshanticut Brook, Furnace Hill Brook, Flat River, Quidneck Brook, and two unnamed tributaries referred to as South Branch Pawtuxet River Tributary A1 and Tributary A2. All the hydraulic models were updated to Hydrologic Engineering Center-River Analysis System (HEC-RAS) version 4.1.0 using steady-state simulations. Updates to the models included incorporation of new field-survey data at structures, high resolution land-surface elevation data, and updated flood flows from a related study. The models were assessed using high-water marks (HWMs) obtained in a related study following the March– April 2010 flood and the simulated water levels at the 0.2-percent annual exceedance probability (AEP), which is the estimated AEP of the 2010 flood in the basin. HWMs were obtained at 110 sites along the main stem of the Pawtuxet River, the North and South Branches of the Pawtuxet River, Pocasset River, Simmons Brook, Furnace Hill Brook, Flat River, and Quidneck Brook. Differences between the 2010 HWM elevations and the simulated 0.2-percent AEP WSEs from flood insurance studies (FISs) and the updated models developed in this study varied with most differences attributed to the magnitude of the 0.2-percent AEP flows. WSEs from the updated models generally are in closer agreement with the observed 2010 HWMs than with the FIS WSEs. The improved agreement of the updated simulated water elevations to observed 2010 HWMs provides a measure of the hydraulic model performance, which indicates the updated models better represent flooding at other AEPs than the existing FIS models.

Hydraulic modeling of stream channels and structures in Harbor and Crow Hollow Brooks, Meriden, Connecticut

USGS Publications Warehouse

Weiss, Lawrence A.; Sears, Michael P.; Cervione, Michael A.

1994-01-01

Effects of urbanization have increased the frequency and size of floods along certain reaches of Harbor Brook and Crow Hollow Brook in Meriden, Conn. A floodprofile-modeling study was conducted to model the effects of selected channel and structural modifications on flood elevations and inundated areas. The study covered the reach of Harbor Brook downstream from Interstate 691 and the reach of Crow Hollow Brook downstream from Johnson Avenue. Proposed modifications, which include changes to bank heights, channel geometry, structural geometry, and streambed armoring on Harbor Brook and changes to bank heights on Crow Hollow Brook, significantly lower flood elevations. Results of the modeling indicate a significant reduction of flood elevations for the 10-year, 25-year, 35-year, 50-year, and 100-year flood frequencies using proposed modifications to (1 ) bank heights between Harbor Brook Towers and Interstate 691 on Harbor Brook, and between Centennial Avenue and Johnson Avenue on Crow Hollow Brook; (2) channel geometry between Coe Avenue and Interstate 69 1 on Harbor Brook; (3) bridge and culvert opening geometry between Harbor Brook Towers and Interstate 691 on Harbor Brook; and (4) channel streambed armoring between Harbor Brook Towers and Interstate 691 on Harbor Brook. The proposed modifications were developed without consideration of cost-benefit ratios.

77 FR 73394 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... and modified elevations, and communities affected for Mercer County, Pennsylvania (All Jurisdictions... determinations of Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs for communities participating... not be construed to mean that the community must change any existing ordinances that are more...

78 FR 22222 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-15

... of referenced elevations, effective and modified elevations, and communities affected for Mercer...) and modified BFEs for communities participating in the National Flood Insurance Program (NFIP), in... CFR 60.3, are minimum requirements. They should not be construed to mean that the community must...

Development of flood profiles and flood-inundation maps for the Village of Killbuck, Ohio

USGS Publications Warehouse

Ostheimer, Chad J.

2013-01-01

Digital flood-inundation maps for a reach of Killbuck Creek near the Village of Killbuck, Ohio, were created by the U.S. Geological Survey (USGS), in cooperation with Holmes County, Ohio. The inundation maps depict estimates of the areal extent of flooding corresponding to water levels (stages) at the USGS streamgage Killbuck Creek near Killbuck (03139000) and were completed as part of an update to Federal Emergency Management Agency Flood-Insurance Study. The maps were provided to the National Weather Service (NWS) for incorporation into a Web-based flood-warning system that can be used in conjunction with NWS flood-forecast data to show areas of predicted flood inundation associated with forecasted flood-peak stages. The digital maps also have been submitted for inclusion in the data libraries of the USGS interactive Flood Inundation Mapper. Data from the streamgage can be used by emergency-management personnel, in conjunction with the flood-inundation maps, to help determine a course of action when flooding is imminent. Flood profiles for selected reaches were prepared by calibrating a steady-state step-backwater model to an established streamgage rating curve. The step-backwater model then was used to determine water-surface-elevation profiles for 10 flood stages at the streamgage with corresponding streamflows ranging from approximately the 50- to 0.2-percent annual exceedance probabilities. The computed flood profiles were used in combination with digital elevation data to delineate flood-inundation areas.

Optimal house elevation for reducing flood-related losses

NASA Astrophysics Data System (ADS)

Xian, Siyuan; Lin, Ning; Kunreuther, Howard

2017-05-01

FEMA recommends that houses in coastal flood zones be elevated to at least 1 foot above the base flood elevation (BFE). However, this guideline is not specific and ignores characteristics of houses that affect their vulnerability. An economically optimal elevation level (OEL) is proposed that minimizes the combined cost of elevation and cumulative insurance premiums over the lifespan of the house. As an illustration, analysis is performed for various coastal houses in Ortley Beach, NJ. Compared with the strategy of raising houses to 1 foot above BFE, the strategy of raising houses to their OELs is much more economical for the homeowners. Elevating to the OELs also significantly reduces government spending on subsidizing low-income homeowners through, for example, a voucher program, to mitigate flood risk. These results suggest that policy makers should consider vulnerability factors in developing risk-reduction strategies. FEMA may recommend OELs to homeowners based on their flood hazards as well as house characteristics or at least providing more information and tools to homeowners to assist them in making more economical decisions. The OEL strategy can also be coupled with a voucher program to make the program more cost-effective.

Hydrological and hydraulic models for determination of flood-prone and flood inundation areas

NASA Astrophysics Data System (ADS)

Aksoy, Hafzullah; Sadan Ozgur Kirca, Veysel; Burgan, Halil Ibrahim; Kellecioglu, Dorukhan

2016-05-01

Geographic Information Systems (GIS) are widely used in most studies on water resources. Especially, when the topography and geomorphology of study area are considered, GIS can ease the work load. Detailed data should be used in this kind of studies. Because of, either the complication of the models or the requirement of highly detailed data, model outputs can be obtained fast only with a good optimization. The aim in this study, firstly, is to determine flood-prone areas in a watershed by using a hydrological model considering two wetness indexes; the topographical wetness index, and the SAGA (System for Automated Geoscientific Analyses) wetness index. The wetness indexes were obtained in the Quantum GIS (QGIS) software by using the Digital Elevation Model of the study area. Flood-prone areas are determined by considering the wetness index maps of the watershed. As the second stage of this study, a hydraulic model, HEC-RAS, was executed to determine flood inundation areas under different return period-flood events. River network cross-sections required for this study were derived from highly detailed digital elevation models by QGIS. Also river hydraulic parameters were used in the hydraulic model. Modelling technology used in this study is made of freely available open source softwares. Based on case studies performed on watersheds in Turkey, it is concluded that results of such studies can be used for taking precaution measures against life and monetary losses due to floods in urban areas particularly.

Productivity responses of Acer rubrum and Taxodium distichum seedlings to elevated CO2 and flooding

USGS Publications Warehouse

Vann, C.D.; Megonigal, J.P.

2002-01-01

Elevated levels of atmospheric CO2 are expected to increase photosynthetic rates of C3 tree species, but it is uncertain whether this will result in an increase in wetland seedling productivity. Separate short-term experiments (12 and 17 weeks) were performed on two wetland tree species, Taxodium distichum and Acer rubrum, to determine if elevated CO2 would influence the biomass responses of seedlings to flooding. T. distichum were grown in replicate glasshouses (n = 2) at CO2 concentrations of 350 or 700 ppm, and A. rubrum were grown in growth chambers at CO2 concentrations of 422 or 722 ppm. Both species were grown from seed. The elevated CO2 treatment was crossed with two water table treatments, flooded and non-flooded. Elevated CO2 increased leaf-level photosynthesis, whole-plant photosynthesis, and trunk diameter of T. distichum in both flooding treatments, but did not increase biomass of T. distichum or A. rubrum. Flooding severely reduced biomass, height, and leaf area of both T. distichum and A. rubrum. Our results suggest that the absence of a CO2-induced increase in growth may have been due to an O2 limitation on root production even though there was a relatively deep (??? 10 cm) aerobic soil surface in the non-flooded treatment. ?? 2001 Elsevier Science Ltd. All rights reserved.

Modeling Stochastic Boundary Conditions in a Coastal Catchment using a Bayesian Network: An Application to the Houston Ship Channel, Texas

NASA Astrophysics Data System (ADS)

Couasnon, Anaïs; Sebastian, Antonia; Morales-Nápoles, Oswaldo

2017-04-01

Recent research has highlighted the increased risk of compound flooding in the U.S. In coastal catchments, an elevated downstream water level, resulting from high tide and/or storm surge, impedes drainage creating a backwater effect that may exacerbate flooding in the riverine environment. Catchments exposed to tropical cyclone activity along the Gulf of Mexico and Atlantic coasts are particularly vulnerable. However, conventional flood hazard models focus mainly on precipitation-induced flooding and few studies accurately represent the hazard associated with the interaction between discharge and elevated downstream water levels. This study presents a method to derive stochastic boundary conditions for a coastal watershed. Mean daily discharge and maximum daily residual water levels are used to build a non-parametric Bayesian network (BN) based on copulas. Stochastic boundary conditions for the watershed are extracted from the BN and input into a 1-D process-based hydraulic model to obtain water surface elevations in the main channel of the catchment. The method is applied to a section of the Houston Ship Channel (Buffalo Bayou) in Southeast Texas. Data at six stream gages and two tidal stations are used to build the BN and 100-year joint return period events are modeled. We find that the dependence relationship between the daily residual water level and the mean daily discharge in the catchment can be represented by a Gumbel copula (Spearman's rank correlation coefficient of 0.31) and that they result in higher water levels in the mid- to upstream reaches of the watershed than when modeled independently. This indicates that conventional (deterministic) methods may underestimate the flood hazard associated with compound flooding in the riverine environment and that such interactions should not be neglected in future coastal flood hazard studies.

75 FR 77762 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-14

... Flooding source(s) elevation in feet above Communities affected ground [caret] Elevation in meters (MSL... South Monroe Village. Lane. Just upstream of High +5,491 Line Canal. Box Elder Creek Approximately 1,400...,773 downstream of East Arapahoe Road. Goldsmith Gulch West Tributary......... Approximately 400 feet...

Flood study of the Suncook River in Epsom, Pembroke, and Allenstown, New Hampshire, 2009

USGS Publications Warehouse

Flynn, Robert H.

2010-01-01

On May 15, 2006, a breach in the riverbank caused an avulsion in the Suncook River in Epsom, NH. The breach in the riverbank and subsequent avulsion changed the established flood zones along the Suncook River; therefore, a new flood study was needed to reflect this change and aid in flood recovery and restoration. For this flood study, the hydrologic and hydraulic analyses for the Suncook River were conducted by the U.S. Geological Survey, in cooperation with the Federal Emergency Management Agency. This report presents water-surface elevations and profiles determined using the U.S. Army Corps of Engineers one-dimensional Hydrologic Engineering Center River Analysis System model, also known as HEC-RAS. Steady-state water-surface profiles were developed for the Suncook River from its confluence with the Merrimack River in the Village of Suncook (in Allenstown and Pembroke, NH) to the upstream corporate limit of the town of Epsom, NH (approximately 15.9 river miles). Floods of magnitudes that are expected to be equaled or exceeded once on the average during any 2-, 5-, 10-, 25-, 50-, 100-, or 500-year period (recurrence interval) were modeled using HEC-RAS. These flood events are referred to as the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year floods and have a 50-, 20-, 10-, 4-, 2-, 1-, and 0.2-percent chance, respectively, of being equaled or exceeded during any year. The 10-, 50-, 100-, and 500-year flood events are important for flood-plain management, determination of flood-insurance rates, and design of structures such as bridges and culverts. The analyses in this study reflect flooding potentials that are based on existing conditions in the communities of Epsom, Pembroke, and Allenstown at the time of completion of this study (2009). Changes in the 100-year recurrence-interval flood elevation from the 1979 flood study were typically less than 2 feet with the exception of a location 900 feet upstream from the avulsion that, because of backwater from the dams in the abandoned channel, was 12 feet higher in the 1979 flood study than in this study.

76 FR 8965 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... buildings. Comments on any aspect of the Flood Insurance Study and FIRM, other than the proposed BFEs, will.... Approximately 1,320 None +410 feet upstream of Uncle Duck Road. Hall Branch At the Shaws Creek None +426...

Method for estimating potential wetland extent by utilizing streamflow statistics and flood-inundation mapping techniques: Pilot study for land along the Wabash River near Terre Haute, Indiana

USGS Publications Warehouse

Kim, Moon H.; Ritz, Christian T.; Arvin, Donald V.

2012-01-01

Potential wetland extents were estimated for a 14-mile reach of the Wabash River near Terre Haute, Indiana. This pilot study was completed by the U.S. Geological Survey in cooperation with the U.S. Department of Agriculture, Natural Resources Conservation Service (NRCS). The study showed that potential wetland extents can be estimated by analyzing streamflow statistics with the available streamgage data, calculating the approximate water-surface elevation along the river, and generating maps by use of flood-inundation mapping techniques. Planning successful restorations for Wetland Reserve Program (WRP) easements requires a determination of areas that show evidence of being in a zone prone to sustained or frequent flooding. Zone determinations of this type are used by WRP planners to define the actively inundated area and make decisions on restoration-practice installation. According to WRP planning guidelines, a site needs to show evidence of being in an "inundation zone" that is prone to sustained or frequent flooding for a period of 7 consecutive days at least once every 2 years on average in order to meet the planning criteria for determining a wetland for a restoration in agricultural land. By calculating the annual highest 7-consecutive-day mean discharge with a 2-year recurrence interval (7MQ2) at a streamgage on the basis of available streamflow data, one can determine the water-surface elevation corresponding to the calculated flow that defines the estimated inundation zone along the river. By using the estimated water-surface elevation ("inundation elevation") along the river, an approximate extent of potential wetland for a restoration in agricultural land can be mapped. As part of the pilot study, a set of maps representing the estimated potential wetland extents was generated in a geographic information system (GIS) application by combining (1) a digital water-surface plane representing the surface of inundation elevation that sloped in the downstream direction of flow and (2) land-surface elevation data. These map products from the pilot study will aid the NRCS and its partners with the onsite inundation-zone verification in agricultural land for a potential restoration and will assist in determining at what elevation to plant hardwood trees for increased survivability on ground above frequently flooded terraces.

Simulated and observed 2010 flood-water elevations in selected river reaches in the Moshassuck and Woonasquatucket River Basins, Rhode Island

USGS Publications Warehouse

Zarriello, Phillip J.; Straub, David E.; Westenbroek, Stephen M.

2014-01-01

Heavy persistent rains from late February through March 2010 caused severe flooding and set, or nearly set, peaks of record for streamflows and water levels at many long-term U.S. Geological Survey streamgages in Rhode Island. In response to this flood, hydraulic models were updated for selected reaches covering about 33 river miles in Moshassuck and Woonasquatucket River Basins from the most recent approved Federal Emergency Management Agency flood insurance study (FIS) to simulate water-surface elevations (WSEs) from specified flows and boundary conditions. Reaches modeled include the main stem of the Moshassuck River and its main tributary, the West River, and three tributaries to the West River—Upper Canada Brook, Lincoln Downs Brook, and East Branch West River; and the main stem of the Woonasquatucket River. All the hydraulic models were updated to Hydrologic Engineering Center-River Analysis System (HEC-RAS) version 4.1.0 and incorporate new field-survey data at structures, high-resolution land-surface elevation data, and flood flows from a related study. The models were used to simulate steady-state WSEs at the 1- and 2-percent annual exceedance probability (AEP) flows, which is the estimated AEP of the 2010 flood in the Moshassuck River Basin and the Woonasquatucket River, respectively. The simulated WSEs were compared to the high-water mark (HWM) elevation data obtained in these basins in a related study following the March–April 2010 flood, which included 18 HWMs along the Moshassuck River and 45 HWMs along the Woonasquatucket River. Differences between the 2010 HWMs and the simulated 2- and 1-percent AEP WSEs from the FISs and the updated models developed in this study varied along the reach. Most differences could be attributed to the magnitude of the 2- and 1-percent AEP flows used in the FIS and updated model flows. Overall, the updated model and the FIS WSEs were not appreciably different when compared to the observed 2010 HWMs along the Woonasquatucket and Moshassuck Rivers.

Flood-inundation map library for the Licking River and South Fork Licking River near Falmouth, Kentucky

USGS Publications Warehouse

Lant, Jeremiah G.

2016-09-19

Digital flood inundation maps for a 17-mile reach of Licking River and 4-mile reach of South Fork Licking River near Falmouth, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with Pendleton County and the U.S. Army Corps of Engineers–Louisville District. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://wim.usgs.gov/FIMI/FloodInundationMapper.html, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the Licking River at Catawba, Ky., (station 03253500) and the USGS streamgage on the South Fork Licking River at Hayes, Ky., (station 03253000). Current conditions (2015) for the USGS streamgages may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis). In addition, the streamgage information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The flood hydrograph forecasts provided by the NWS are usually collocated with USGS streamgages. The forecasted peak-stage information, also available on the NWS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation.In this study, flood profiles were computed for the Licking River reach and South Fork Licking River reach by using a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current (2015) stage-discharge relations for the Licking River at Catawba, Ky., and the South Fork Licking River at Hayes, Ky., USGS streamgages. The calibrated model was then used to calculate 60 water-surface profiles for a sequence of flood stages, at 2-foot intervals, referenced to the streamgage datum and ranging from an elevation near bankfull to the elevation associated with a major flood that occurred in the region in 1997. To delineate the flooded area at each interval flood stage, the simulated water-surface profiles were combined with a digital elevation model of the study area by using geographic information system software.The availability of these flood inundation maps for Falmouth, Ky., along with online information regarding current stages from the USGS streamgages and forecasted stages from the NWS, provides emergency management personnel and local residents with information that is critical for flood response activities such as evacuations, road closures, and post-flood recovery efforts.

Simulations of Flooding on Pea River and Whitewater Creek in the Vicinity of the Proposed Elba Bypass at Elba, Alabama

USGS Publications Warehouse

Hedgecock, T. Scott

2003-01-01

A two-dimensional finite-element surface-water model was used to study the effects of proposed modifications to the State Highway 203 corridor (proposed Elba Bypass/relocated U.S. Highway 84) on water-surface elevations and flow distributions during flooding in the Pea River and Whitewater Creek Basins at Elba, Coffee County, Alabama. Flooding was first simulated for the March 17, 1990, flood, using the 1990 flood-plain conditions to calibrate the model to match measured data collected by the U.S. Geological Survey and the U.S. Army Corps of Engineers after the flood. After model calibration, the effects of flooding were simulated for four scenarios: (1) floods having the 50- and 100-year recurrence intervals for the existing flood-plain, bridge, highway, and levee conditions; (2) floods having the 50- and 100-year recurrence intervals for the existing flood-plain and levee conditions with the State Highway 203 embankment and bridge removed; (3) floods having the 50- and 100-year recurrence intervals for the existing flood-plain, bridge, and highway conditions with proposed modifications (elevating) to the levee; and (4) floods having the 50- and 100-year recurrence intervals for the proposed conditions reflecting the Elba Bypass and modified levee. The simulation of floodflow for the Pea River and Whitewater Creek flood of March 17, 1990, in the study reach compared closely to flood profile data obtained after the flood. The flood of March 17, 1990, had an estimated peak discharge of 58,000 cubic feet per second at the gage (just below the confluence) and was estimated to be between a 50-year and 100-year flood event. The estimated peak discharge for Pea River and Whitewater Creek was 40,000 and 42,000 cubic feet per second, respectively. Simulation of floodflows for the 50-year flood (51,400 cubic feet per second) at the gage for existing flood-plain, bridge, highway, and levee conditions indicated that about 31 percent of the peak flow was conveyed by the State Highway 203 bridge over Whitewater Creek, approximately 12 percent overtopped the State Highway 203 embankment, and about 57 percent was conveyed by the Pea River flood plain east of State Highway 125. For this simulation, flow from Pea River (2,380 cubic feet per second) overtopped State Highway 125 and crossed over into the Whitewater Creek flood plain north of State Highway 203, creating one common flood plain. The water-surface elevation estimated at the downstream side of the State Highway 203 bridge crossing Whitewater Creek was 202.82 feet. The girders for both the State Highway 203 and U.S. Highway 84 bridges were partially submerged, but U.S. Highway 84 was not overtopped. For the 100-year flood (63,500 cubic feet per second) at the gage, the simulation indicated that about 25 percent of the peak flow was conveyed by the State Highway 203 bridge over Whitewater Creek, approximately 24 percent overtopped the State Highway 203 embankment, and about 51 percent was conveyed by the Pea River flood plain east of State Highway 125. The existing levee adjacent to Whitewater Creek was overtopped by a flow of 3,200 cubic feet per second during the 100-year flood. For this simulation, flow from Pea River (6,710 cubic feet per second) overtopped State Highway 125 and crossed over into the Whitewater Creek flood plain north of State Highway 203. The water-surface elevation estimated at the downstream side of the State Highway 203 bridge crossing Whitewater Creek was 205.60 feet. The girders for both the State Highway 203 and U.S. Highway 84 bridges were partially submerged, and the west end of the U.S. Highway 84 bridge was overtopped. Simulation of floodflows for the 50-year flood at the gage for existing flood-plain and levee conditions, but with the State Highway 203 embankment and bridge removed, yielded a lower water-surface elevation (202.90 feet) upstream of this bridge than that computed for the existing conditions. For the 100-year flood, the simulation indi

Swiss Re Global Flood Hazard Zones: Know your flood risk

NASA Astrophysics Data System (ADS)

Vinukollu, R. K.; Castaldi, A.; Mehlhorn, J.

2012-12-01

Floods, among all natural disasters, have a great damage potential. On a global basis, there is strong evidence of increase in the number of people affected and economic losses due to floods. For example, global insured flood losses have increased by 12% every year since 1970 and this is expected to further increase with growing exposure in the high risk areas close to rivers and coastlines. Recently, the insurance industry has been surprised by the large extent of losses, because most countries lack reliable hazard information. One example has been the 2011 Thailand floods where millions of people were affected and the total economic losses were 30 billion USD. In order to assess the flood risk across different regions and countries, the flood team at Swiss Re based on a Geomorphologic Regression approach, developed in house and patented, produced global maps of flood zones. Input data for the study was obtained from NASA's Shuttle Radar Topographic Mission (SRTM) elevation data, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model (GDEM) and HydroSHEDS. The underlying assumptions of the approach are that naturally flowing rivers shape their channel and flood plain according to basin inherent forces and characteristics and that the flood water extent strongly depends on the shape of the flood plain. On the basis of the catchment characteristics, the model finally calculates the probability of a location to be flooded or not for a defined return period, which in the current study was set to 100 years. The data is produced at a 90-m resolution for latitudes 60S to 60N. This global product is now used in the insurance industry to inspect, inform and/or insure the flood risk across the world.

Simulation of Flood Profiles for Catoma Creek near Montgomery, Alabama, 2008

USGS Publications Warehouse

Lee, K.G.; Hedgecock, T.S.

2008-01-01

A one-dimensional step-backwater model was used to simulate flooding conditions for Catoma Creek near Montgomery, Alabama. A peak flow of 50,000 cubic feet per second was computed by the U.S. Geological Survey for the March 1990 flood at the Norman Bridge Road gaging station. Using this estimated peak flow, flood-plain surveys with associated roughness coefficients, and surveyed high-water marks for the March 1990 flood, a flow model was calibrated to closely match the known event. The calibrated model then was used to simulate flooding for the 10-, 50-, 100-, and 500-year recurrence-interval floods. The 100-year flood stage for the Alabama River also was computed in the vicinity of the Catoma Creek confluence using observed high-water profiles from the 1979 and 1990 floods and gaging-station data. The results indicate that the 100-year flood profile for Catoma Creek within the 15-mile study reach is about 2.5 feet higher, on average, than the profile published by the Federal Emergency Management Agency. The maximum and minimum differences are 6.0 feet and 0.8 foot, respectively. All water-surface elevations computed for the 100-year flood are higher than those published by the Federal Emergency Management Agency. The 100-year flood stage computed for the Alabama River in the vicinity of the Catoma Creek confluence was about 4.5 feet lower than the elevation published by the Federal Emergency Management Agency. The results of this study provide the community with flood-profile information that can be used for flood-plain mitigation, future development, and safety plans for the city.

Flood-inundation maps for an 8.9-mile reach of the South Fork Little River at Hopkinsville, Kentucky

USGS Publications Warehouse

Lant, Jeremiah G.

2013-01-01

Digital flood-inundation maps for an 8.9-mile reach of South Fork Little River at Hopkinsville, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Hopkinsville Community Development Services. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage at South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky (station no. 03437495). Current conditions for the USGS streamgage may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis/inventory?agency_code=USGS&site_no=03437495). In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service flood warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often co-located at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the South Fork Little River reach by using HEC-RAS, a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (2012) stage-discharge relation at the South Fork Little River at Highway 68 By-Pass at Hopkinsville, Kentucky, streamgage and measurements collected during recent flood events. The calibrated model was then used to calculate 13 water-surface profiles for a sequence of flood stages, most at 1-foot intervals, referenced to the streamgage datum and ranging from a stage near bank full to the estimated elevation of the 1.0-percent annual exceedance probability flood at the streamgage. To delineate the flooded area at each interval flood stage, the simulated water-surface profiles were combined with a Digital Elevation Model (DEM) of the study area by using Geographic Information System (GIS) software. The DEM consisted of bare-earth elevations within the study area and was derived from a Light Detection And Ranging (LiDAR) dataset having a 3.28-foot horizontal resolution. These flood-inundation maps, along with online information regarding current stages from USGS streamgage and forecasted stages from the NWS, provide emergency management and local residents with critical information for flood response activities such as evacuations, road closures, and post-flood recovery efforts.

Geomorphic changes caused by the 2011 flood at selected sites along the lower Missouri River and comparison to historical floods: Chapter H in 2011 floods of the central United States

USGS Publications Warehouse

Juracek, Kyle E.

2014-01-01

An analysis of recent and historical U.S. Geological Survey streamgage information was used to assess geomorphic changes caused by the 2011 flood, in comparison to selected historical floods, at three streamgage sites along the lower Missouri River—Sioux City, Iowa; Omaha, Nebraska; and Kansas City, Missouri. Channel-width change was not evident at the three streamgage sites following the 2011 flood and likely was inhibited by bank stabilization. Pronounced changes in channel-bed elevation were indicated. At Sioux City and Omaha, the geomorphic effects of the 2011 flood were similar in terms of the magnitude of channelbed scour and recovery. At both sites, the 2011 flood caused pronounced scour (about 3 feet) of the channel bed; however, at Omaha, most of the channel-bed scour occurred after the flood had receded. More than 1 year after the flood, the channel bed had only partially recovered (about 1 foot) at both sites. Pronounced scour (about 3 feet at Sioux City and about 1.5 feet at Omaha) also was caused by the 1952 flood, which had a substantially larger peak discharge but was much shorter in duration at both sites. Again, at Omaha, most of the channel- bed scour occurred after the flood had receded. At Sioux City, substantial recovery of the channel bed (about 2.5 feet) was documented 1 year after the 1952 flood. Recovery to the pre-flood elevation was complete by April 1954. The greater recovery following the 1952 flood, compared to the 2011 flood, likely was related to a more abundant sediment supply because the flood predated the completion of most of the main-stem dam, channelization, and bank stabilization projects. At Omaha, following the 1952 flood, the channel bed never fully recovered to its pre-flood elevation. The geomorphic effect of the 2011 flood at Kansas City was fill (about 1 foot) on the channel bed followed by relative stability. The 1952 flood, which had a substantially larger peak discharge but was much shorter in duration, caused modest fill (about 0.5 foot) on the channel bed. The 1993 flood, which also had a substantially larger peak discharge but was much shorter in duration, caused pronounced scour of the channel bed (possibly as much as 4 feet). Similar to the floods at Omaha, much of the channel-bed scour at Kansas City occurred after the 1993 flood had receded. More than 1 year after the 1993 flood, following partial recovery (about 1 foot), the channel bed had stabilized, at least temporarily. Following the 1993 flood, the channel bed never fully recovered to its pre-flood elevation. For each flood in the post-dam era that resulted in substantial channel-bed scour (Sioux City in 2011, Omaha in 2011, Kansas City in 1993), recovery of the channel bed to its pre-flood elevation had not occurred more than 1 year after the flood (20 years after the 1993 flood at Kansas City). Thus, the possibility exists that channel-bed scour caused by large floods may have a cumulative effect along the lower Missouri River. The persistence of the flood-related decreases in channel-bed elevation may be indicative of the constrained ability of the channel to recover given a limited sediment supply caused by one or more of the following factors: upstream storage of sediment in reservoirs, bank stabilization, commercial sand dredging, depletion of readily available sediment by the flood, and a lack of post-flood sediment contributions from tributaries.

77 FR 20999 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-09

... set forth below: * Elevation in feet (NGVD) + Elevation in feet (NAVD) Depth in feet Flooding source(s..., and Incorporated Areas Docket No.: FEMA-B-1100 Mississippi River Approximately 11.2 miles +585 City of.... Approximately 12.8 miles +594 upstream of State Highway 136. * National Geodetic Vertical Datum. + North...

78 FR 45938 - Final Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

...] Final Flood Hazard Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Final notice. SUMMARY: Flood hazard determinations, which may include additions or modifications of Base Flood Elevations (BFEs), base flood depths, Special Flood Hazard Area (SFHA) boundaries or zone designations, or...

Framework for National Flood Risk Assessment for Canada

NASA Astrophysics Data System (ADS)

Elshorbagy, A. A.; Raja, B.; Lakhanpal, A.; Razavi, S.; Ceola, S.; Montanari, A.

2016-12-01

Worldwide, floods have been identified as a standout amongst the most widely recognized catastrophic events, resulting in the loss of life and property. These natural hazards cannot be avoided, but their consequences can certainly be reduced by having prior knowledge of their occurrence and impact. In the context of floods, the terms occurrence and impact are substituted by flood hazard and flood vulnerability, respectively, which collectively define the flood risk. There is a high need for identifying the flood-prone areas and to quantify the risk associated with them. The present study aims at delivering flood risk maps, which prioritize the potential flood risk areas in Canada. The methodology adopted in this study involves integrating various available spatial datasets such as nightlights satellite imagery, land use, population and the digital elevation model, to build a flexible framework for national flood risk assessment for Canada. The flood risk framework assists in identifying the flood-prone areas and evaluating the associated risk. All these spatial datasets were brought to a common GIS platform for flood risk analysis. The spatial datasets deliver the socioeconomic and topographical information that is required for evaluating the flood vulnerability and flood hazard, respectively. Nightlights have been investigated as a tool to be used as a proxy for the human activities to identify areas with regard to economic investment. However, other datasets, including existing flood protection measures, we added to identify a realistic flood assessment framework. Furthermore, the city of Calgary was used as an example to investigate the effect of using Digital Elevation Models (DEMs) of varying resolutions on risk maps. Along with this, the risk map for the city was further enhanced by including the population data to give a social dimension to the risk map. Flood protection measures play a major role by significantly reducing the flood risk of events with a specific return period. An analysis to update the risk maps when information on protection measures is available was carried out for the city of Winnipeg, Canada. The proposed framework is a promising approach to identify and prioritize flood-prone areas, which are in need of intervention or detailed studies.

Flooding Frequency Alters Vegetation in Isolated Wetlands

USGS Publications Warehouse

Haag, Kim H.; Lee, Terrie M.

2006-01-01

Many isolated wetlands in central Florida occur as small, shallow depressions scattered throughout the karst topography of the region. In these wetlands, the water table approaches land surface seasonally, and water levels and flooding frequency are largely determined by differences between precipitation and evapotranspiration. Because much of the region is flat with little topographic relief, small changes in wetland water levels can cause large changes in wetland surface area. Persistent changes in wetland flooding frequencies, as a result of changes in rainfall or human activity, can cause a substantial change in the vegetation of thousands of acres of land. Understanding the effect that flooding frequency has on wetland vegetation is important to assessing the overall ecological status of wetlands. Wetland bathymetric mapping, when combined with water-level data and vegetation assessments, can enable scientists to determine the frequency of flooding at different elevations in a wetland and describe the effects of flooding frequency on wetland vegetation at those elevations. Five cypress swamps and five marshes were studied by the U.S. Geological Survey (USGS) during 2000-2004, as part of an interdisciplinary study of isolated wetlands in central Florida (Haag and others, 2005). Partial results from two of these marshes are described in this report.

44 CFR 65.3 - Requirement to submit new technical data.

Code of Federal Regulations, 2012 CFR

2012-10-01

... base flood elevations may increase or decrease resulting from physical changes affecting flooding... physical changes affecting flooding conditions, risk premium rates and flood plain management requirements...

44 CFR 65.3 - Requirement to submit new technical data.

Code of Federal Regulations, 2013 CFR

2013-10-01

... base flood elevations may increase or decrease resulting from physical changes affecting flooding... physical changes affecting flooding conditions, risk premium rates and flood plain management requirements...

44 CFR 65.3 - Requirement to submit new technical data.

Code of Federal Regulations, 2014 CFR

2014-10-01

... base flood elevations may increase or decrease resulting from physical changes affecting flooding... physical changes affecting flooding conditions, risk premium rates and flood plain management requirements...

Hydrologic and Hydraulic Analyses of Selected Streams in Lorain County, Ohio, 2003

USGS Publications Warehouse

Jackson, K. Scott; Ostheimer, Chad J.; Whitehead, Matthew T.

2003-01-01

Hydrologic and hydraulic analyses were done for selected reaches of nine streams in Lorain County Ohio. To assess the alternatives for flood-damage mitigation, the Lorain County Engineer and the U.S. Geological Survey (USGS) initiated a cooperative study to investigate aspects of the hydrology and hydraulics of the nine streams. Historical streamflow data and regional regression equations were used to estimate instantaneous peak discharges for floods having recurrence intervals of 2, 5, 10, 25, 50, and 100 years. Explanatory variables used in the regression equations were drainage area, main-channel slope, and storage area. Drainage areas of the nine stream reaches studied ranged from 1.80 to 19.3 square miles. The step-backwater model HEC-RAS was used to determine water-surface-elevation profiles for the 10-year-recurrence-interval (10-year) flood along a selected reach of each stream. The water-surface pro-file information was used then to generate digital mapping of flood-plain boundaries. The analyses indicate that at the 10-year flood elevation, road overflow results at numerous hydraulic structures along the nine streams.

76 FR 50918 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-17

...Base (1% annual-chance) Flood Elevations (BFEs) and modified BFEs are made final for the communities listed below. The BFEs and modified BFEs are the basis for the floodplain management measures that each community is required either to adopt or to show evidence of being already in effect in order to qualify or remain qualified for participation in the National Flood Insurance Program (NFIP).

Elevated view of city from incline Johnstown Local Flood ...

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

Elevated view of city from incline - 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

Flood-inundation maps and updated components for a flood-warning system or the City of Marietta, Ohio and selected communities along the Lower Muskingum River and Ohio River

USGS Publications Warehouse

Whitehead, Matthew T.; Ostheimer, Chad J.

2014-01-01

Flood profiles for selected reaches were prepared by calibrating steady-state step-backwater models to selected streamgage rating curves. The step-backwater models were used to determine water-surface-elevation profiles for up to 12 flood stages at a streamgage with corresponding stream-flows ranging from approximately the 10- to 0.2-percent chance annual-exceedance probabilities for each of the 3 streamgages that correspond to the flood-inundation maps. Additional hydraulic modeling was used to account for the effects of backwater from the Ohio River on water levels in the Muskingum River. The computed longitudinal profiles of flood levels were used with a Geographic Information System digital elevation model (derived from light detection and ranging) to delineate flood-inundation areas. Digital maps showing flood-inundation areas overlain on digital orthophotographs were prepared for the selected floods.

Simulation of Columbia River Floods in the Hanford Reach

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

Waichler, Scott R.; Serkowski, John A.; Perkins, William A.

Columbia River water elevations and flows in the Hanford Reach affect the environment and facilities along the shoreline, including movement of contaminants in groundwater, fish habitat, and infrastructure subject to flooding. This report describes the hydraulic simulation of hypothetical flood flows using the best available topographic and bathymetric data for the Hanford Reach and the Modular Aquatic Simulation System in 1 Dimension (MASS1) hydrodynamic model. The MASS1 model of the Hanford Reach was previously calibrated to field measurements of water surface elevations. The current model setup can be used for other studies of flow, water levels, and temperature in themore » Reach. The existing MASS1 channel geometry and roughness and other model configuration inputs for the Hanford Reach were used for this study, and previous calibration and validation results for the model are reprinted here for reference. The flood flows for this study were simulated by setting constant flow rates obtained from the U.S. Army Corps of Engineers (USACE) for the Columbia, Snake, and Yakima Rivers, and a constant water level at McNary Dam, and then running the model to steady state. The discharge levels simulated were all low-probability events; for example, a 100-year flood is one that would occur on average every 100 years, or put another way, in any given year there is a 1% chance that a discharge of that level or higher will occur. The simulated floods and their corresponding Columbia River discharges were 100-year (445,000 cfs), 500-year (520,000 cfs), and the USACE-defined Standard Project Flood (960,000 cfs). The resulting water levels from the steady-state floods can be viewed as “worst case” outcomes for the respective discharge levels. The MASS1 output for water surface elevations was converted to the North American Vertical Datum of 1988 and projected across the channel and land surface to enable mapping of the floodplain for each scenario. Floodplain maps show that for the 100-year and 500-year discharge levels, flooding is mainly confined to the topographic trench that is the river channel. The flooded area for the Standard Project Flood extends out of the channel area in some places, particularly in the 100-F Area. All of the output from the simulations have been archived and are available for future investigations in the Hanford Reach.« less

Leveraging North Carolina's QL2 Lidar to Quantify Sensitivity of National Water Model Derived Flood Inundation Extent to DEM Resolution

NASA Astrophysics Data System (ADS)

Lovette, J. P.; Lenhardt, W. C.; Blanton, B.; Duncan, J. M.; Stillwell, L.

2017-12-01

The National Water Model (NWM) has provided a novel framework for near real time flood inundation mapping across CONUS at a 10m resolution. In many regions, this spatial scale is quickly being surpassed through the collection of high resolution lidar (1 - 3m). As one of the leading states in data collection for flood inundation mapping, North Carolina is currently improving their previously available 20 ft statewide elevation product to a Quality Level 2 (QL2) product with a nominal point spacing of 0.7 meters. This QL2 elevation product increases the ground points by roughly ten times over the previous statewide lidar product, and by over 250 times when compared to the 10m NED elevation grid. When combining these new lidar data with the discharge estimates from the NWM, we can further improve statewide flood inundation maps and predictions of at-risk areas. In the context of flood risk management, these improved predictions with higher resolution elevation models consistently represent an improvement on coarser products. Additionally, the QL2 lidar also includes coarse land cover classification data for each point return, opening the possibility for expanding analysis beyond the use of only digital elevation models (e.g. improving estimates of surface roughness, identifying anthropogenic features in floodplains, characterizing riparian zones, etc.). Using the NWM Height Above Nearest Drainage approach, we compare flood inundation extents derived from multiple lidar-derived grid resolutions to assess the tradeoff between precision and computational load in North Carolina's coastal river basins. The elevation data distributed through the state's new lidar collection program provide spatial resolutions ranging from 5-50 feet, with most inland areas also including a 3 ft product. Data storage increases by almost two orders of magnitude across this range, as does processing load. In order to further assess the validity of the higher resolution elevation products on flood inundation, we examine the NWM outputs from Hurricane Matthew, which devastated southeastern North Carolina in October 2016. When compared with numerous surveyed high water marks across the coastal plain, this assessment provides insight on the impacts of grid resolution on flood inundation extent.

Hydrologic, soil, and vegetation gradients in remnant and constructed riparian wetlands in west-central Missouri, 2001-04

USGS Publications Warehouse

Heimann, David C.; Mettler-Cherry, Paige A.

2004-01-01

A study was conducted by the U.S. Geological Survey in cooperation with the Missouri Department of Conservation at the Four Rivers Conservation Area (west-central Missouri), between January 2001 and March 2004, to examine the relations between environmental factors (hydrology, soils, elevation, and landform type) and the spatial distribution of vegetation in remnant and constructed riparian wetlands. Vegetation characterization included species composition of ground, understory, and overstory layers in selected landforms of a remnant bottomland hardwood ecosystem, monitoring survival and growth of reforestation plots in leveed and partially leveed constructed wetlands, and determining gradients in colonization of herbaceous vegetation in a constructed wetland. Similar environmental factors accounted for variation in the distribution of ground, understory, and overstory vegetation in the remnant bottomland forest plots. The primary measured determining factors in the distribution of vegetation in the ground layer were elevation, soil texture (clay and silt content), flooding inundation duration, and ponding duration, while the distribution of vegetation in the understory layer was described by elevation, soil texture (clay, silt, and sand content), total flooding and ponding inundation duration, and distance from the Marmaton or Little Osage River. The primary measured determining factors in the distribution of overstory vegetation in Unit 1 were elevation, soil texture (clay, silt, and sand content), total flooding and ponding inundation duration, ponding duration, and to some extent, flooding inundation duration. Overall, the composition and structure of the remnant bottomland forest is indicative of a healthy, relatively undisturbed flood plain forest. Dominant species have a distribution of individuals that shows regeneration of these species with significant recruitment in the smaller size classes. The bottomland forest is an area whose overall hydrology has not been significantly altered; however, portions of the area have suffered from hydrologic alteration by a drainage ditch that is resulting in the displacement of swamp and marsh species by colonizing shrub and tree species. This area likely will continue to develop into an immature flood plain forest under the current (2004) hydrologic regime. Reforestation plots in constructed wetlands consisted of sampling survival and growth of multiple tree species (Quercus palustris, pin oak; Carya illinoiensis, pecan) established under several production methods and planted at multiple elevations. Comparison of survival between tree species and production types showed no significant differences for all comparisons. Survival was high for both species and all production types, with the highest mortality seen in the mounded root production method (RPM?) Quercus palustris (pin oak, 6.9 percent), while direct seeded Quercus palustris at middle elevation and bare root Quercus palustris seedlings at the low elevation plots had 100 percent survival. Measures of growth (diameter and height) were assessed among species, production types, and elevation by analyzing relative growth. The greatest rate of tree diameter (72.3 percent) and height (65.3 percent) growth was observed for direct seeded Quercus palustris trees planted at a middle elevation site. Natural colonized vegetation data were collected at multiple elevations within an abandoned cropland area of a constructed wetland. The primary measured determining factors in the distribution of herbaceous vegetation in this area were elevation, ponding duration, and soil texture. Richness, evenness, and diversity were all significantly greater in the highest elevation plots as a result of more recent disturbance in this area. While flood frequency and duration define the delivery mechanism for inundation on the flood plain, it is the duration of ponding and amount of 'topographic capture' of these floodwaters in fluvial lan

Determination of channel capacity of the Sacramento River between Ordbend and Glenn, Butte and Glenn counties, California

USGS Publications Warehouse

Simpson, R.G.

1976-01-01

The adequacy of an 8.5-mi reach of the Sacramento River to carry flood flows is evaluated. The reach studied is in Butte and Glenn Counties, California, and extends northward from the present east-bank Sacramento River Flood Control Project levee near Glenn upstream to the Ord Ferry gaging station near Ordbend. There is a west-bank levee throughout the study reach. Flows analyzed range from 11,500 to 265,000 cfs. Computed water-surface elevations are based on topography obtained during September through November 1974. The present Sacramento River Flood Control Project levees at the downstream end of the study reach near Glenn are designed to contain flows up to 150,000 cfs. Water-surface elevations computed for flows of this magnitude are about 6 to 8 ft below the top of the existing west-bank levee throughout the study reach. (Woodard-USGS)

River analysis and floodplain modeling using HEC-GeoRAS/RAS, GIS and ArcGIS: a case study for the Salinas River

NASA Astrophysics Data System (ADS)

Mishra, P. K.; Bernini Campos, H. E.

2016-12-01

The lower portion of the Salinas River in Monterey bay, California has a history of flood, lots of study has been made ab out the water quality since the river provides water for the crops around, but is still in need a detailed study about the river behavior and flood analysis. The floods did significant damage, affecting valuable landing farms, residences and businesses in Monterey County. The first step for this study is comprehend and collect the river bathymetry and surroundings and then analyze the discharge and how it is going to change with time. This thesis develops a model about the specific site, recruiting real data from GIS and performing a flow simulation according to flow data provided by USGS, to verify water surface elevation and floodplain. The ArcMap, developed by ESRI, was used along with an extension (HEC-GeoRAS) because it was indeed the most appropriate model to work with the Digital Elevation Model, develop the floodplain and characterizing the land surface accurately in the study site. The HEC-RAS software, developed by US Army Corp of Engineers, was used to compute one-dimension steady flow and two-dimension unsteady flow, providing flow velocity, water surface elevation and profiles, total surface area, head and friction loss and other characteristics, allowing the analysis of the flow. A mean discharge, a mean peak streamflow and a peak discharge were used for the steady flow and a Hydrograph was used for the unsteady flow, both are based on the 1995 flood and discharge history. This study provides important information about water surface elevation and water flow, allowing stakeholders and the government to analyze solutions to avoid damage to the society and landowners.

Probabilistic flood extent estimates from social media flood observations

NASA Astrophysics Data System (ADS)

Brouwer, Tom; Eilander, Dirk; van Loenen, Arnejan; Booij, Martijn J.; Wijnberg, Kathelijne M.; Verkade, Jan S.; Wagemaker, Jurjen

2017-05-01

The increasing number and severity of floods, driven by phenomena such as urbanization, deforestation, subsidence and climate change, create a growing need for accurate and timely flood maps. In this paper we present and evaluate a method to create deterministic and probabilistic flood maps from Twitter messages that mention locations of flooding. A deterministic flood map created for the December 2015 flood in the city of York (UK) showed good performance (F(2) = 0.69; a statistic ranging from 0 to 1, with 1 expressing a perfect fit with validation data). The probabilistic flood maps we created showed that, in the York case study, the uncertainty in flood extent was mainly induced by errors in the precise locations of flood observations as derived from Twitter data. Errors in the terrain elevation data or in the parameters of the applied algorithm contributed less to flood extent uncertainty. Although these maps tended to overestimate the actual probability of flooding, they gave a reasonable representation of flood extent uncertainty in the area. This study illustrates that inherently uncertain data from social media can be used to derive information about flooding.

77 FR 55784 - Proposed Flood Elevation Determinations; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-11

... the flooding sources for Franklin County, North Carolina and Incorporated Areas. The flooding source... ``Franklin County, North Carolina, and Incorporated Areas'' addressed several flooding sources, including Taylors Creek. The proposed rule incorrectly listed the flooding source name as Taylors Branch instead of...

77 FR 18844 - Proposed Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-28

...: Internal Agency Docket No. FEMA-B-1236] Proposed Flood Hazard Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice. SUMMARY: Comments are requested on proposed flood hazard determinations, which may include additions or modifications of any Base Flood Elevation (BFE), base flood depth...

78 FR 43899 - Changes in Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-22

..., ``Flood Insurance.'') Dated: July 2, 2013. Roy E. Wright, Deputy Associate Administrator for Mitigation...] Changes in Flood Hazard Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Final notice. SUMMARY: New or modified Base (1% annual-chance) Flood Elevations (BFEs), base flood depths...

78 FR 49277 - Proposed Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-13

...: Internal Agency Docket No. FEMA-B-1345] Proposed Flood Hazard Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice. SUMMARY: Comments are requested on proposed flood hazard determinations, which may include additions or modifications of any Base Flood Elevation (BFE), base flood depth...

Flood-inundation maps for a 6.5-mile reach of the Kentucky River at Frankfort, Kentucky

USGS Publications Warehouse

Lant, Jeremiah G.

2013-01-01

Digital flood-inundation maps for a 6.5-mile reach of Kentucky River at Frankfort, Kentucky, were created by the U.S. Geological Survey (USGS) in cooperation with the City of Frankfort Office of Emergency Management. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage Kentucky River at Lock 4 at Frankfort, Kentucky (station no. 03287500). Current conditions for the USGS streamgage may be obtained online at the USGS National Water Information System site (http://waterdata.usgs.gov/nwis/inventory?agency_code=USGS&site_no=03287500). In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system (http:/water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often colocated at USGS streamgages. The forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the Kentucky River reach by using HEC–RAS, a one-dimensional step-backwater model developed by the U.S. Army Corps of Engineers. The hydraulic model was calibrated by using the most current (2013) stage-discharge relation for the Kentucky River at Lock 4 at Frankfort, Kentucky, in combination with streamgage and high-water-mark measurements collected for a flood event in May 2010. The calibrated model was then used to calculate 26 water-surface profiles for a sequence of flood stages, at 1-foot intervals, referenced to the streamgage datum and ranging from a stage near bankfull to the elevation that breached the levees protecting the City of Frankfort. To delineate the flooded area at each interval flood stage, the simulated water-surface profiles were combined with a digital elevation model (DEM) of the study area by using geographic information system software. The DEM consisted of bare-earth elevations within the study area and was derived from a Light Detection And Ranging (LiDAR) dataset having a 5.0-foot horizontal resolution and an accuracy of 0.229 foot. The availability of these maps, along with Internet information regarding current stages from USGS streamgages and forecasted stages from the NWS, provides emergency management personnel and local residents with critical information for flood response activities such as evacuations, road closures, and postflood recovery efforts.

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2010 CFR

2010-10-01

... STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or...

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2013 CFR

2013-10-01

... STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or...

Flood elevations for the Soleduck River at Sol Duc Hot Springs, Clallam County, Washington

USGS Publications Warehouse

Nelson, L.M.

1983-01-01

Elevations and inundation areas of a 100-year flood of the Soleduck River, Washington, were determined by the U.S. Geological Survey for the area in the vicinity of the Sol Duc Hot Springs resort, a public facility in the Olympic National Park that under Federal law must be located beyond or protected from damage by a 100-year flood. Results show that most flooding could be eliminated by raising parts of an existing dike. In general, little flood damage is expected, except at the southern end of an undeveloped airstrip that could become inundated and hazardous due to flow from a tributary. The airstrip is above the 100-year flood of the Soleduck River.

77 FR 20997 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-09

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS... in the table below. FOR FURTHER INFORMATION CONTACT: Luis Rodriguez, Chief, Engineering Management...

75 FR 18072 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2010-0003] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS... Management Branch, Mitigation Directorate, Federal Emergency Management Agency, 500 C Street, SW., Washington...

76 FR 26941 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-10

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS... in the table below. FOR FURTHER INFORMATION CONTACT: Luis Rodriguez, Chief, Engineering Management...

Estimated flood peak discharges on Twin, Brock, and Lightning creeks, Southwest Oklahoma City, Oklahoma, May 8, 1993

USGS Publications Warehouse

Tortorelli, R.L.

1996-01-01

The flash flood in southwestern Oklahoma City, Oklahoma, May 8, 1993, was the result of an intense 3-hour rainfall on saturated ground or impervious surfaces. The total precipitation of 5.28 inches was close to the 3-hour, 100-year frequency and produced extensive flooding. The most serious flooding was on Twin, Brock, and Lightning Creeks. Four people died in this flood. Over 1,900 structures were damaged along the 3 creeks. There were about $3 million in damages to Oklahoma City public facilities, the majority of which were in the three basins. A study was conducted to determine the magnitude of the May 8, 1993, flood peak discharge in these three creeks in southwestern Oklahoma City and compare these peaks with published flood estimates. Flood peak-discharge estimates for these creeks were determined at 11 study sites using a step-backwater analysis to match the flood water-surface profiles defined by high-water marks. The unit discharges during peak runoff ranged from 881 cubic feet per second per square mile for Lightning Creek at SW 44th Street to 3,570 cubic feet per second per square mile for Brock Creek at SW 59th Street. The ratios of the 1993 flood peak discharges to the Federal Emergency Management Agency 100-year flood peak discharges ranged from 1.25 to 3.29. The water-surface elevations ranged from 0.2 foot to 5.9 feet above the Federal Emergency Management Agency 500-year flood water-surface elevations. The very large flood peaks in these 3 small urban basins were the result of very intense rainfall in a short period of time, close to 100 percent runoff due to ground surfaces being essentially impervious, and the city streets acting as efficient conveyances to the main channels. The unit discharges compare in magnitude to other extraordinary Oklahoma urban floods.

Moisture performance of insulated, raised, wood-frame floors : a study of twelve houses in southern Louisiana

Treesearch

Samuel V. Glass; Charles G. Carll; Jay P. Curole; Matthew D. Voitier

2010-01-01

In flood-prone areas, elevating a building’s floor system above the anticipated flood level can significantly limit the extent of property damage associated with flooding. In hot and humid climates, such as the Gulf Coast region, raised floor systems may, however, be at risk for seasonal moisture accumulation, as the majority of residential buildings in such climates...

Predicted high-water elevations for selected flood events at the Albert Pike Recreation Area, Ouachita National Forest

Treesearch

D.A. Marion

2012-01-01

The hydraulic characteristics are determined for the June 11, 2010, flood on the Little Missouri River at the Albert Pike Recreation Area in Arkansas. These characteristics are then used to predict the high-water elevations for the 10-, 25-, 50-, and 100-year flood events in the Loop B, C, and D Campgrounds of the recreation area. The peak discharge and related...

Application of satellite products and hydrological modelling for flood early warning

NASA Astrophysics Data System (ADS)

Koriche, Sifan A.; Rientjes, Tom H. M.

2016-06-01

Floods have caused devastating impacts to the environment and society in Awash River Basin, Ethiopia. Since flooding events are frequent, this marks the need to develop tools for flood early warning. In this study, we propose a satellite based flood index to identify the runoff source areas that largely contribute to extreme runoff production and floods in the basin. Satellite based products used for development of the flood index are CMORPH (Climate Prediction Center MORPHing technique: 0.25° by 0.25°, daily) product for calculation of the Standard Precipitation Index (SPI) and a Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) for calculation of the Topographic Wetness Index (TWI). Other satellite products used in this study are for rainfall-runoff modelling to represent rainfall, potential evapotranspiration, vegetation cover and topography. Results of the study show that assessment of spatial and temporal rainfall variability by satellite products may well serve in flood early warning. Preliminary findings on effectiveness of the flood index developed in this study indicate that the index is well suited for flood early warning. The index combines SPI and TWI, and preliminary results illustrate the spatial distribution of likely runoff source areas that cause floods in flood prone areas.

[Responses of Cynodon dactylon population in hydro-fluctuation belt of Three Gorges Reservoir area to flooding-drying habitat change].

PubMed

Hong, Ming; Guo, Quan-Shu; Nie, Bi-Hong; Kang, Yi; Pei, Shun-Xiang; Jin, Jiang-Qun; Wang, Xiang-Fu

2011-11-01

This paper studied the population density, morphological characteristics, and biomass and its allocation of Cynodon dactylon at different altitudinal sections of the hydro-fluctuation belt in Three Gorges Reservoir area, based on located observations. At the three altitudinal sections, the population density of C. dactylon was in the order of shallow water section (165-170 m elevation) > non-flooded section (above 172 m elevation) > deep water section (145-150 m elevation), the root diameter and root length were in the order of deep water section > shallow water section > non-flooded section, the total biomass, root biomass, stem biomass, leaf biomass, and stem biomass allocation ratio were in the order of the shallow water section > non-flooded section > deep water section, and the root biomass allocation ratio, leaf biomass allocation ratio, and underground biomass/aboveground biomass were in the order of deep water section > shallow water section > non-flooded section. The unique adaption strategies of C. dactylon to the flooding-drying habitat change in the shallow water section were the accelerated elongation growth and the increased stem biomass allocation, those in the deep water section were the increased node number of primary and secondary branches, increased number of the branches, and increased leaf biomass allocation, whereas the common strategies in the shallow and deep water sections were the accelerated root growth and the increased tillering and underground biomass allocation for preparing nutrition and energy for the rapid growth in terrestrial environment.

Assessment of Three Flood Hazard Mapping Methods: A Case Study of Perlis

NASA Astrophysics Data System (ADS)

Azizat, Nazirah; Omar, Wan Mohd Sabki Wan

2018-03-01

Flood is a common natural disaster and also affect the all state in Malaysia. Regarding to Drainage and Irrigation Department (DID) in 2007, about 29, 270 km2 or 9 percent of region of the country is prone to flooding. Flood can be such devastating catastrophic which can effected to people, economy and environment. Flood hazard mapping can be used is an important part in flood assessment to define those high risk area prone to flooding. The purposes of this study are to prepare a flood hazard mapping in Perlis and to evaluate flood hazard using frequency ratio, statistical index and Poisson method. The six factors affecting the occurrence of flood including elevation, distance from the drainage network, rainfall, soil texture, geology and erosion were created using ArcGIS 10.1 software. Flood location map in this study has been generated based on flooded area in year 2010 from DID. These parameters and flood location map were analysed to prepare flood hazard mapping in representing the probability of flood area. The results of the analysis were verified using flood location data in year 2013, 2014, 2015. The comparison result showed statistical index method is better in prediction of flood area rather than frequency ratio and Poisson method.

Topography and flooding of coastal ecosystems on the Yukon-Kuskokwim Delta, Alaska: Implications for sea level rise

USGS Publications Warehouse

Jorgenson, Torre; Ely, Craig R.

2001-01-01

We measured surface elevations, stage of annual peak flooding, and sedimentation along 10 toposequences across coastal ecosystems on the Yukon-Kuskokwim (Y-K) Delta in western Alaska during 1994-1998 to assess some of the physical processes affecting ecosystem distribution. An ecotype was assigned to each of 566 points, and differences in elevations among 24 ecotypes were analyzed within individual toposequences and across the 40 x 40-km study area. Elevations of vegetated ecotypes along the longest toposequence rose only ~1 m over a distance of 7.5 km, and mean elevations of most ecotype across the study area were within 0.5 m of mean higher-high water (1.47 m). During 1994 to 1998, monitoring of annual peak stage using crest gauges revealed flooding from the highest fall storm surge reached 2.58 m (1.11 m above mean higher-high tide). In each year, only the highest surface was unaffected by flooding. Mean annual sedimentation rates for the various ecotypes were 8.0 ram/y on tidal flats, 1.4 to 3.8 mm/y on the active floodplain, 0.1-0.2 mm/y on the inactive floodplain, and 0 mm/ on the abandoned floodplain. If sea levels in the Bering Sea rise ~0.5 m by 2100, as predicted by some on a global basis, large portions of the coastal margin of the delta could be regularly inundated by water during high tides, and even the highest ecotypes could be affected by storm surges. Predicting the extent of future inundation is difficult, however, because of the changes in the ground-surface elevation through sedimentation, organic matter accumulation, and permafrost development.

77 FR 51743 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-27

... modified elevations, and communities affected for the City of Newport News, Virginia. Specifically, it.... The table, entitled ``City of Newport News, Virgina'' addressed the flooding sources Newmarket Creek... Modified City of Newport News, Virginia Virginia City of Newport News.... Newmarket Creek Approximately 0...

75 FR 7956 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-23

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1073] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS. ACTION: Interim rule. SUMMARY: This interim rule lists...

77 FR 73398 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1085] Proposed Flood Elevation Determinations AGENCY..., identified by Docket No. FEMA-B- 1085, to Luis Rodriguez, Chief, Engineering Management Branch, Federal...

77 FR 73393 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1085] Proposed Flood Elevation Determinations AGENCY..., identified by Docket No. FEMA-B- 1085, to Luis Rodriguez, Chief, Engineering Management Branch, Federal...

76 FR 3524 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

... proof Flood Insurance Study and FIRM available at the address cited below for each community. The BFEs...-Long Run Road. Duck Run (backwater effects from Scioto Approximately 547 feet +535 Unincorporated Areas of River). upstream of Duck Run- Scioto County. Otway Road. Just downstream of +535 McDermott Pond...

76 FR 272 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-04

... review the proof Flood Insurance Study and FIRM available at the address cited below for each community... feet +738 upstream of State Route 564. West Fork Duck Creek Approximately 0.41 mile +734 Unincorporated....: FEMA-B-1025 Duck Creek Approximately 3,950 feet +622 Town of Liberty, downstream of South Yale...

Flood-inundation maps for the Leaf River at Hattiesburg, Mississippi

USGS Publications Warehouse

Storm, John B.

2012-01-01

Digital flood-inundation maps for a 1.7-mile reach of the Leaf River were developed by the U.S. Geological Survey (USGS) in cooperation with the City of Hattiesburg, City of Petal, Forrest County, Mississippi Emergency Management Agency, Mississippi Department of Homeland Security, and the Emergency Management District. The Leaf River study reach extends from just upstream of the U.S. Highway 11 crossing to just downstream of East Hardy/South Main Street and separates the cities of Hattiesburg and Petal, Mississippi. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water-surface elevations (stages) at the USGS streamgage at Leaf River at Hattiesburg, Mississippi (02473000). Current conditions at the USGS streamgage may be obtained through the National Water Information System Web site at http://waterdata.usgs.gov/ms/nwis/uv/?site_no=02473000&PARAmeter_cd=00065,00060. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood-warning system (http://water.weather.gov/ahps/). The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. The forecasted peak-stage information, available on the AHPS Web site, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the stream reach by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the Leaf River at Hattiesburg, Mississippi, streamgage and documented high-water marks from recent and historical floods. The hydraulic model was then used to determine 13 water-surface profiles for flood stages at 1.0-foot intervals referenced to the streamgage datum and ranging from bankfull to approximately the highest recorded water-surface elevation at the streamgage. The simulated water-surface profiles were then combined with a geographic information system digital elevation model [derived from Light Detection and Ranging (LiDAR) data having a 0.6-foot vertical accuracy and 9.84-foot horizontal resolution] in order to delineate the area flooded at each 1-foot increment of stream stage. The availability of these maps, when combined with real-time stage information from USGS streamgages and forecasted stream stage from the NWS, provides emergency management personnel and residents with critical information during flood-response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.

44 CFR 64.3 - Flood Insurance Maps.

Code of Federal Regulations, 2012 CFR

2012-10-01

... tidal floods (coastal high hazard area) V1-30, VE Area of special flood hazards, with water surface elevations determined and with velocity, that is inundated by tidal floods (coastal high hazard area) V0 Area..., but possible, mudslide hazards E Area of special flood-related erosion hazards. Areas identified as...

44 CFR 64.3 - Flood Insurance Maps.

Code of Federal Regulations, 2013 CFR

2013-10-01

... tidal floods (coastal high hazard area) V1-30, VE Area of special flood hazards, with water surface elevations determined and with velocity, that is inundated by tidal floods (coastal high hazard area) V0 Area..., but possible, mudslide hazards E Area of special flood-related erosion hazards. Areas identified as...

44 CFR 64.3 - Flood Insurance Maps.

Code of Federal Regulations, 2014 CFR

2014-10-01

... tidal floods (coastal high hazard area) V1-30, VE Area of special flood hazards, with water surface elevations determined and with velocity, that is inundated by tidal floods (coastal high hazard area) V0 Area..., but possible, mudslide hazards E Area of special flood-related erosion hazards. Areas identified as...

Floods in the Wapsipinicon River Basin, Iowa

USGS Publications Warehouse

Schwob, Harlan H.

1971-01-01

Flood-profile sheets show profiles of actual flood occurrences and computed profiles of the 25- and 50-year floods at most locations. These sheets also contain tabulations of the flood discharges profiled. A low-water profile and tabulated discharge indicate the range in elevation and discharge along the streams.

44 CFR 67.8 - Appeal procedure.

Code of Federal Regulations, 2014 CFR

2014-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.8 Appeal procedure. (a) If a community appeals the proposed flood...

Flood Map for the Winooski River in Waterbury, Vermont, 2014

USGS Publications Warehouse

Olson, Scott A.

2015-01-01

High-water marks from Tropical Storm Irene were available for seven locations along the study reach. The highwater marks were used to estimate water-surface profiles and discharges resulting from Tropical Storm Irene throughout the study reach. From a comparison of the estimated water-surface profile for Tropical Storm Irene with the water-surface profiles for the 1- and 0.2-percent annual exceedance probability (AEP) floods, it was determined that the high-water elevations resulting from Tropical Storm Irene exceeded the estimated 1-percent AEP flood throughout the Winooski River study reach but did not exceed the estimated 0.2-percent AEP flood at any location within the study reach.

76 FR 13571 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-14

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2008-0020; Internal Agency Docket No. FEMA-B-1072] Proposed Flood Elevation Determinations AGENCY... June 13, 2011. ADDRESSES: You may submit comments, identified by Docket No. FEMA-B- 1072, to Luis...

76 FR 61279 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-04

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2011-0002] Final Flood Elevation Determinations Correction In rule document 2011-15507, beginning on page 36373, in the issue of Wednesday June 22, 2011, make the following corrections: Sec. 67.11...

76 FR 50443 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-15

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2011-0002; Internal Agency Docket No. FEMA-B-1196] Proposed Flood Elevation Determinations Correction In proposed rule document 2011-16640 appearing on pages 39063 through 39067 in the issue of Tuesday...

76 FR 12308 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-07

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2011-0002; Internal Agency Docket No. FEMA-B-1174] Proposed Flood Elevation Determinations Correction In proposed rule document 2011-2281 beginning on page 5769 in the issue of Wednesday, February 2...

76 FR 58409 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-21

... changes in BFEs are in accordance with 44 CFR 65.4. National Environmental Policy Act. This interim rule is categorically excluded from the requirements of 44 CFR part 10, Environmental Consideration. An environmental impact assessment has not been prepared. Regulatory Flexibility Act. As flood elevation...

76 FR 20554 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... management requirements. The community may at any time enact stricter requirements of its own or pursuant to... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS...

76 FR 8900 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... management requirements. The community may at any time enact stricter requirements of its own or pursuant to... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS...

77 FR 73396 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-10

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1089] Proposed Flood Elevation Determinations AGENCY.... ADDRESSES: You may submit comments, identified by Docket No. FEMA-B- 1089, to Luis Rodriguez, Chief...

Estimation of Damage Costs Associated with Flood Events

NASA Astrophysics Data System (ADS)

Andrews, T. A.; Wauthier, C.; Zipp, K.

2017-12-01

This study investigates the possibility of creating a mathematical function that enables the estimation of flood-damage costs. We begin by examining the costs associated with past flood events in the United States. The data on these tropical storms and hurricanes are provided by the National Oceanic and Atmospheric Administration. With the location, extent of flooding, and damage reparation costs identified, we analyze variables such as: number of inches rained, land elevation, type of landscape, region development in regards to building density and infrastructure, and population concentration. We seek to identify the leading drivers of high flood-damage costs and understand which variables play a large role in the costliness of these weather events. Upon completion of our mathematical analysis, we turn out attention to the 2017 natural disaster of Texas. We divide the region, as we did above, by land elevation, type of landscape, region development in regards to building density and infrastructure, and population concentration. Then, we overlay the number of inches rained in those regions onto the divided landscape and apply our function. We hope to use these findings to estimate the potential flood-damage costs of Hurricane Harvey. This information is then transformed into a hazard map that could provide citizens and businesses of flood-stricken zones additional resources for their insurance selection process.

Effects of anthropogenic land-subsidence on inundation dynamics: the case study of Ravenna, Italy

NASA Astrophysics Data System (ADS)

Carisi, Francesca; Domeneghetti, Alessio; Castellarin, Attilio

2016-05-01

Can differential land-subsidence significantly alter river flooding dynamics, and thus flood risk in flood prone areas? Many studies show how the lowering of the coastal areas is closely related to an increase in the flood-hazard due to more important tidal flooding and see level rise. The literature on the relationship between differential land-subsidence and possible alterations to riverine flood-hazard of inland areas is still sparse, although several geographical areas characterized by significant land-subsidence rates during the last 50 years experienced intensification in both inundation magnitude and frequency. We investigate the possible impact of a significant differential ground lowering on flood hazard over a 77 km2 area around the city of Ravenna, in Italy. The rate of land-subsidence in the study area, naturally in the order of a few mm year-1, dramatically increased up to 110 mm year-1 after World War II, primarily due to groundwater pumping and gas production platforms. The result was a cumulative drop that locally exceeds 1.5 m. Using a recent digital elevation model (res. 5 m) and literature data on land-subsidence, we constructed a ground elevation model over the study area in 1897 and we characterized either the current and the historical DEM with or without road embankments and land-reclamation channels in their current configuration. We then considered these four different topographic models and a two-dimensional hydrodynamic model to simulate and compare the inundation dynamics associated with a levee failure scenario along embankment system of the river Montone, which flows eastward in the southern portion of the study area. For each topographic model, we quantified the flood hazard in terms of maximum water depth (h) and we compared the actual effects on flood-hazard dynamics of differential land-subsidence relative to those associated with other man-made topographic alterations, which resulted to be much more significant.

A simple methodology to produce flood risk maps consistent with FEMA's base flood elevation maps: Implementation and validation over the entire contiguous United States

NASA Astrophysics Data System (ADS)

Goteti, G.; Kaheil, Y. H.; Katz, B. G.; Li, S.; Lohmann, D.

2011-12-01

In the United States, government agencies as well as the National Flood Insurance Program (NFIP) use flood inundation maps associated with the 100-year return period (base flood elevation, BFE), produced by the Federal Emergency Management Agency (FEMA), as the basis for flood insurance. A credibility check of the flood risk hydraulic models, often employed by insurance companies, is their ability to reasonably reproduce FEMA's BFE maps. We present results from the implementation of a flood modeling methodology aimed towards reproducing FEMA's BFE maps at a very fine spatial resolution using a computationally parsimonious, yet robust, hydraulic model. The hydraulic model used in this study has two components: one for simulating flooding of the river channel and adjacent floodplain, and the other for simulating flooding in the remainder of the catchment. The first component is based on a 1-D wave propagation model, while the second component is based on a 2-D diffusive wave model. The 1-D component captures the flooding from large-scale river transport (including upstream effects), while the 2-D component captures the flooding from local rainfall. The study domain consists of the contiguous United States, hydrologically subdivided into catchments averaging about 500 km2 in area, at a spatial resolution of 30 meters. Using historical daily precipitation data from the Climate Prediction Center (CPC), the precipitation associated with the 100-year return period event was computed for each catchment and was input to the hydraulic model. Flood extent from the FEMA BFE maps is reasonably replicated by the 1-D component of the model (riverine flooding). FEMA's BFE maps only represent the riverine flooding component and are unavailable for many regions of the USA. However, this modeling methodology (1-D and 2-D components together) covers the entire contiguous USA. This study is part of a larger modeling effort from Risk Management Solutions° (RMS) to estimate flood risk associated with extreme precipitation events in the USA. Towards this greater objective, state-of-the-art models of flood hazard and stochastic precipitation are being implemented over the contiguous United States. Results from the successful implementation of the modeling methodology will be presented.

76 FR 56724 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-14

.../town/county Source of flooding Location ** ground [caret] Elevation in meters (MSL) Existing Modified... Datum. Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ** BFEs to... upstream of Cradduck Road None +876 Oklahoma Unincorporated Areas of Town Branch Approximately 400 feet...

Flood-hazard mapping in Honduras in response to Hurricane Mitch

USGS Publications Warehouse

Mastin, M.C.

2002-01-01

The devastation in Honduras due to flooding from Hurricane Mitch in 1998 prompted the U.S. Agency for International Development, through the U.S. Geological Survey, to develop a country-wide systematic approach of flood-hazard mapping and a demonstration of the method at selected sites as part of a reconstruction effort. The design discharge chosen for flood-hazard mapping was the flood with an average return interval of 50 years, and this selection was based on discussions with the U.S. Agency for International Development and the Honduran Public Works and Transportation Ministry. A regression equation for estimating the 50-year flood discharge using drainage area and annual precipitation as the explanatory variables was developed, based on data from 34 long-term gaging sites. This equation, which has a standard error of prediction of 71.3 percent, was used in a geographic information system to estimate the 50-year flood discharge at any location for any river in the country. The flood-hazard mapping method was demonstrated at 15 selected municipalities. High-resolution digital-elevation models of the floodplain were obtained using an airborne laser-terrain mapping system. Field verification of the digital elevation models showed that the digital-elevation models had mean absolute errors ranging from -0.57 to 0.14 meter in the vertical dimension. From these models, water-surface elevation cross sections were obtained and used in a numerical, one-dimensional, steady-flow stepbackwater model to estimate water-surface profiles corresponding to the 50-year flood discharge. From these water-surface profiles, maps of area and depth of inundation were created at the 13 of the 15 selected municipalities. At La Lima only, the area and depth of inundation of the channel capacity in the city was mapped. At Santa Rose de Aguan, no numerical model was created. The 50-year flood and the maps of area and depth of inundation are based on the estimated 50-year storm tide.

Variability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in the Grand Canyon

NASA Astrophysics Data System (ADS)

Mueller, Erich R.; Grams, Paul E.; Hazel, Joseph E.; Schmidt, John C.

2018-01-01

Sandbars are iconic features of the Colorado River in the Grand Canyon, Arizona, U.S.A. Following completion of Glen Canyon Dam in 1963, sediment deficit conditions caused erosion of eddy sandbars throughout much of the 360 km study reach downstream from the dam. Controlled floods in 1996, 2004, and 2008 demonstrated that sand on the channel bed could be redistributed to higher elevations, and that floods timed to follow tributary sediment inputs would increase suspended sand concentrations during floods. Since 2012, a new management protocol has resulted in four controlled floods timed to follow large inputs of sand from a major tributary. Monitoring of 44 downstream eddy sandbars, initiated in 1990, shows that each controlled flood deposited significant amounts of sand and increased the size of subaerial sandbars. However, the magnitude of sandbar deposition varied from eddy to eddy, even over relatively short distances where main-stem suspended sediment concentrations were similar. Here, we characterize spatial and temporal trends in sandbar volume and site-scale (i.e., individual eddy) sediment storage as a function of flow, channel, and vegetation characteristics that reflect the reach-scale (i.e., kilometer-scale) hydraulic environment. We grouped the long-term monitoring sites based on geomorphic setting and used a principal component analysis (PCA) to correlate differences in sandbar behavior to changes in reach-scale geomorphic metrics. Sites in narrow reaches are less-vegetated, stage changes markedly with discharge, sandbars tend to remain dynamic, and sand storage change dominantly occurs in the eddy compared to the main channel. In wider reaches, where stage-change during floods may be half that of narrow sites, sandbars are more likely to be stabilized by vegetation, and floods tend to aggrade the vegetated sandbar surfaces. In these locations, deposition during controlled floods is more akin to floodplain sedimentation, and the elevation of sandbar surfaces increases with successive floods. Because many sandbars are intermediate to the end members described above, high-elevation bar surfaces stabilized by vegetation often have a more dynamic unvegetated sandbar on the channel-ward margin that aggrades and erodes in response to controlled flood cycles. Ultimately, controlled floods have been effective at increasing averaged sandbar volumes, and, while bar deposition during floods decreases through time where vegetation has stabilized sandbars, future controlled floods are likely to continue to result in deposition in a majority of the river corridor. Supplementary Fig. 2 Relation between the total site and high-elevation discharge-volume relation slope for all sites where both relations are available (n = 33). Supplementary Fig. 3 Change in sandbar volume since 1990 for Marble versus Grand Canyon sites. Solid vertical gray lines indicate controlled floods, and dashed vertical gray lines indicate other high test flows in 1997 and 2000 as discussed in the text. ​Photographs by U.S. Geological Survey, 2008-2015.

Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA

USGS Publications Warehouse

Kasprak, Alan; Bangen, Sara G.; Buscombe, Daniel; Caster, Joshua; East, Amy; Grams, Paul E.; Sankey, Joel B.

2017-01-01

In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these flood deposits redistributes sediment to higher elevation upland sites, thus maintaining naturallyoccurring aeolian landscapes [Draut, 2012].

76 FR 8984 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... buildings. Comments on any aspect of the Flood Insurance Study and FIRM, other than the proposed BFEs, will... Glacier Highway. At the Auke Bay ferry [caret]22 [caret]29 terminal. Duck Creek At the downstream side... [caret]52 upstream of Taku Boulevard. East Fork Duck Creek Approximately 150 feet [caret]31 [caret]34...

78 FR 45877 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... proof Flood Insurance Study and FIRM available at the address cited below for each community. The BFEs... Highway. At the Auke Bay ferry [caret] 29 terminal. Duck Creek At the downstream side of [caret] 23 City.... East Fork Duck Creek Approximately 150 feet [caret] 34 City and Borough of downstream of Nancy Juneau...

76 FR 32896 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-07

... buildings. Comments on any aspect of the Flood Insurance Study and FIRM, other than the proposed BFEs, will... Creek confluence. At the downstream side +489 +491 of Oak Gate Lane. Long Branch (of Duck Creek) Bypass.. At the upstream side of +498 +490 City of Mesquite. the Long Branch (of Duck Creek) confluence...

77 FR 51744 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-27

..., FEMA published in the Federal Register a proposed rule that included an erroneous flooding source name for the Town of Livonia in Pointe Coupee Parish, Louisiana. The flooding source name of Bayou Fordoche... Coupee Parish, Louisiana, and Incorporated Areas'' addressed several flooding sources, including Bayou...

44 CFR 67.5 - Right of appeal.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD... community where a proposed flood elevation determination has been made pursuant to section 1363 of the National Flood Insurance Act of 1968, as amended, who believes his property rights to be adversely affected...

44 CFR 67.5 - Right of appeal.

Code of Federal Regulations, 2014 CFR

2014-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD... community where a proposed flood elevation determination has been made pursuant to section 1363 of the National Flood Insurance Act of 1968, as amended, who believes his property rights to be adversely affected...

The development of a hydrologic-hydraulic representation of an urbanscape: the case study of Nashville, Tennessee

NASA Astrophysics Data System (ADS)

Sedlar, F.; Ivanov, V. Y.; Shao, J.; Narayan, U.; Nardi, F.; Adams, T. E.; Merwade, V.; Wright, D. B.; Kim, J.; Fatichi, S.; Rakhmatulina, E.

2013-12-01

Incorporating elevation data into coupled hydraulic and hydrologic models with the use of triangulated irregular networks (TINs) provides a detailed and highly customizable representation of the original domain. Until recently the resolution of such digital elevation models was 1 or 1/3 arc second (10-30 meters). Aided by the use of LiDAR, digital elevation models are now available at the 1/9 arc second resolution (1-3 meters). With elevation data at this level of resolution watershed details that are overlooked at a 10-30 meter resolution can now be resolved and incorporated into the TIN. For urban flood modeling this implies that street level features can be resolved. However to provide a useful picture of the flooding as a whole, this data would need to be integrated across a citywide scale. To prove the feasibility, process, and capabilities of generating such a detailed and large scale TIN, we present a case study of Nashville, TN, USA, during the May 1-2, 2010 flooding, a 1,000 year storm event. With the use of ArcGIS, HEC-RAS, Triangle, and additionally developed processing methodologies, an approach is developed to generate a hydrologically relevant and detailed TIN of the entire urbanscape of Nashville. This TIN incorporates three separate aspects; the watershed, the floodplain, and the city. The watershed component contains the elevation data for the delineated watershed, roughly 1,000 km2 at 1-3 meter resolution. The floodplain encompasses over 300 channel cross sections of the Cumberland River and a delineated floodplain. The city element comprises over 500,000 buildings and all major roadways within the watershed. Once generated, the resulting triangulation of the TIN is optimized with the Triangle software for input to the coupled hydraulic and hydrological model, tRIBS-OFM. Hydrologically relevant areas such as the floodplain are densified and constraints are set on the minimum triangle area for the entire TIN. Upon running the coupled hydraulic and hydrological model with the appropriate forcings, the spatial dynamics of the flooding will then be resolved at a street level across the entire city. The analysis capabilities afforded at this resolution and across such a large area will facilitate urban flood predictions coupled with hydrologic forecasts as well as a better understanding of the spatial dynamics of urban flooding.

78 FR 6743 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-31

... in feet (NGVD) + Elevation in feet (NAVD) Flooding source(s) Location of referenced Depth in feet... downstream of Greely Allen County. Chapel Road. Approximately 750 feet + 965 upstream of Faulkner Road. Dug.... Approximately 100 feet + 827 downstream of North Cable Road. Dug Run Tributary At the Dug Run confluence + 813...

78 FR 5738 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-28

... in feet (NGVD) + Elevation in feet (NAVD) Depth in feet State City/town/county Source of flooding... feet upstream of I-15 +3433 Areas of (westbound). Cascade County. Approximately 1.2 miles upstream of I... feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES Unincorporated...

44 CFR 67.3 - Establishment and maintenance of a flood elevation determination docket (FEDD).

Code of Federal Regulations, 2010 CFR

2010-10-01

... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Establishment and maintenance of a flood elevation determination docket (FEDD). 67.3 Section 67.3 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD...

76 FR 13569 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-14

..., FEMA published in the Federal Register a proposed rule that included erroneous Base Flood Elevation... for the proposed BFE of 1,290 feet, referenced to the North American Vertical Datum of 1988, should... Vertical Datum of 1988, should have located the proposed BFE as being approximately 0.24 mile upstream of...

76 FR 14359 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-16

..., FEMA published in the Federal Register a proposed rule that included erroneous Base Flood Elevation... description for the proposed BFE of 1,032 feet, referenced to the North American Vertical Datum of 1988... description for the proposed BFE of 1,049 feet, referenced to the North American Vertical Datum of 1988...

76 FR 3595 - Proposed Flood Elevation Determinations for Cumberland County, ME (All Jurisdictions)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-20

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2008-0020; Internal Agency Docket No. FEMA-B-1060] Proposed Flood Elevation Determinations for Cumberland County, ME (All Jurisdictions) AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice of...

76 FR 26980 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-10

...-2010-0003; Internal Agency Docket No. FEMA-B-1155] Proposed Flood Elevation Determinations AGENCY... Lake Michigan and White Ditch in La Porte County, Indiana. The City of Michiana Shores should have been listed as the Town of Michiana Shores. DATES: Comments pertaining to the Lake Michigan and White Ditch...

77 FR 66791 - Proposed Flood Elevation Determinations for Wicomico County, MD, and Incorporated Areas

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-07

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 67 [Docket ID FEMA-2010-0003; Internal Agency Docket No. FEMA-B-1085] Proposed Flood Elevation Determinations for Wicomico..., identified by Docket No. FEMA-B- 1085, to Luis Rodriguez, Chief, Engineering Management Branch, Federal...

Therapists' and patients' stress responses during graduated versus flooding in vivo exposure in the treatment of specific phobia: A preliminary observational study.

PubMed

Schumacher, Sarah; Miller, Robert; Fehm, Lydia; Kirschbaum, Clemens; Fydrich, Thomas; Ströhle, Andreas

2015-12-15

Exposure therapy is considered an effective treatment strategy for phobic anxiety, however, it is rarely applied in clinical practice. The under-usage might be due to various factors of which heightened stress levels not only in patients but also in therapists are presumed to be of particular relevance. The present study aimed to investigate whether different forms of exposure might lead to varying physiological and psychological stress responses in therapists and phobic patients. 25 patients with specific phobia underwent individual cognitive behavioural therapy, performed by 25 psychotherapist trainees, applying exposure sessions in graduated form or the flooding technique. Patients and therapists provided subjective evaluations of stress and five saliva samples for analysis of salivary cortisol and alpha-amylase either during two graduated exposure sessions or during one flooding session, while a regular therapy session served as control condition. Therapists displayed heightened salivary alpha-amylase release during exposure of the flooding, but not the graduated, type. Patients showed elevated salivary cortisol during flooding exposure numerically, however, not on a statistically significant level. Therapists reported more pronounced subjective stress during flooding compared to graduated exposure. Elevated stress levels should be addressed in clinical training in order to improve application of exposure in routine practice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cane Creek flood-flow characteristics at State Route 30 near Spencer, Tennessee

USGS Publications Warehouse

Gamble, Charles R.

1983-01-01

The Tennessee Department of Transportation has constructed a new bridge and approaches on State Route 30 over Cane Creek near Spencer, Tennessee. The old bridge and its approaches were fairly low, permitting considerable flow over the road during high floods. The new bridge and its approaches are considerably higher, causing different flow conditions at the site. Analysis of the effects of the new bridge, as compared to the old bridge, on floods of the magnitude of the May 27, 1973, flood is presented. The May 27, 1973, flood was greater than a 100-year flood. Analysis of the 50- and 100-year floods for the new bridge are also presented. Results of the study indicate that the new construction will increase the water-surface elevation for a flood equal to the May 27, 1973, flood by approximately 1 foot upstream from bridge. (USGS)

Quantitative model of the growth of floodplains by vertical accretion

USGS Publications Warehouse

Moody, J.A.; Troutman, B.M.

2000-01-01

A simple one-dimensional model is developed to quantitatively predict the change in elevation, over a period of decades, for vertically accreting floodplains. This unsteady model approximates the monotonic growth of a floodplain as an incremental but constant increase of net sediment deposition per flood for those floods of a partial duration series that exceed a threshold discharge corresponding to the elevation of the floodplain. Sediment deposition from each flood increases the elevation of the floodplain and consequently the magnitude of the threshold discharge resulting in a decrease in the number of floods and growth rate of the floodplain. Floodplain growth curves predicted by this model are compared to empirical growth curves based on dendrochronology and to direct field measurements at five floodplain sites. The model was used to predict the value of net sediment deposition per flood which best fits (in a least squares sense) the empirical and field measurements; these values fall within the range of independent estimates of the net sediment deposition per flood based on empirical equations. These empirical equations permit the application of the model to estimate of floodplain growth for other floodplains throughout the world which do not have detailed data of sediment deposition during individual floods. Copyright (C) 2000 John Wiley and Sons, Ltd.

Response of plant productivity to experimental flooding in a stable and a submerging marsh

USGS Publications Warehouse

Kirwan, Matthew L.; Guntenspergen, Glenn R.

2015-01-01

Recent models of tidal marsh evolution rely largely on the premise that plants are most productive at an optimal flooding regime that occurs when soil elevations are somewhere between mean sea level and mean high tide. Here, we use 4 years of manipulative “marsh organ” flooding experiments to test the generality of this conceptual framework and to examine how the optimal flooding frequency may change between years and locations. In our experiments, above and belowground growth of Schoenoplectus americanus was most rapid when flooded about 40% of the time in a rapidly submerging marsh and when flooded about 25% of the time in a historically stable marsh. Optimum flooding durations were nearly identical in each year of the experiment and did not differ for above and belowground growth. In contrast, above and belowground growth of Spartina patensdecreased monotonically with increased flooding in all years and at both sites, indicating no optimal flooding frequency or elevation relative to sea level. Growth patterns in both species suggest a wider tolerance to flooding, and greater biomass for a given flooding duration, in the rapidly deteriorating marsh.

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.

44 CFR 64.3 - Flood Insurance Maps.

Code of Federal Regulations, 2010 CFR

2010-10-01

... with water surface elevations determined A0 Area of special flood hazards having shallow water depths... insurance rating purposes AH Areas of special flood hazards having shallow water depths and/or unpredictable... of special flood hazards having shallow water depths and/or unpredictable flow paths between (1) and...

Assessing uncertainty in SRTM elevations for global flood modelling

NASA Astrophysics Data System (ADS)

Hawker, L. P.; Rougier, J.; Neal, J. C.; Bates, P. D.

2017-12-01

The SRTM DEM is widely used as the topography input to flood models in data-sparse locations. Understanding spatial error in the SRTM product is crucial in constraining uncertainty about elevations and assessing the impact of these upon flood prediction. Assessment of SRTM error was carried out by Rodriguez et al (2006), but this did not explicitly quantify the spatial structure of vertical errors in the DEM, and nor did it distinguish between errors over different types of landscape. As a result, there is a lack of information about spatial structure of vertical errors of the SRTM in the landscape that matters most to flood models - the floodplain. Therefore, this study attempts this task by comparing SRTM, an error corrected SRTM product (The MERIT DEM of Yamazaki et al., 2017) and near truth LIDAR elevations for 3 deltaic floodplains (Mississippi, Po, Wax Lake) and a large lowland region (the Fens, UK). Using the error covariance function, calculated by comparing SRTM elevations to the near truth LIDAR, perturbations of the 90m SRTM DEM were generated, producing a catalogue of plausible DEMs. This allows modellers to simulate a suite of plausible DEMs at any aggregated block size above native SRTM resolution. Finally, the generated DEM's were input into a hydrodynamic model of the Mekong Delta, built using the LISFLOOD-FP hydrodynamic model, to assess how DEM error affects the hydrodynamics and inundation extent across the domain. The end product of this is an inundation map with the probability of each pixel being flooded based on the catalogue of DEMs. In a world of increasing computer power, but a lack of detailed datasets, this powerful approach can be used throughout natural hazard modelling to understand how errors in the SRTM DEM can impact the hazard assessment.

The Importance of Precise Digital Elevation Models (DEM) in Modelling Floods

NASA Astrophysics Data System (ADS)

Demir, Gokben; Akyurek, Zuhal

2016-04-01

Digital elevation Models (DEM) are important inputs for topography for the accurate modelling of floodplain hydrodynamics. Floodplains have a key role as natural retarding pools which attenuate flood waves and suppress flood peaks. GPS, LIDAR and bathymetric surveys are well known surveying methods to acquire topographic data. It is not only time consuming and expensive to obtain topographic data through surveying but also sometimes impossible for remote areas. In this study it is aimed to present the importance of accurate modelling of topography for flood modelling. The flood modelling for Samsun-Terme in Blacksea region of Turkey is done. One of the DEM is obtained from the point observations retrieved from 1/5000 scaled orthophotos and 1/1000 scaled point elevation data from field surveys at x-sections. The river banks are corrected by using the orthophotos and elevation values. This DEM is named as scaled DEM. The other DEM is obtained from bathymetric surveys. 296 538 number of points and the left/right bank slopes were used to construct the DEM having 1 m spatial resolution and this DEM is named as base DEM. Two DEMs were compared by using 27 x-sections. The maximum difference at thalweg of the river bed is 2m and the minimum difference is 20 cm between two DEMs. The channel conveyance capacity in base DEM is larger than the one in scaled DEM and floodplain is modelled in detail in base DEM. MIKE21 with flexible grid is used in 2- dimensional shallow water flow modelling. The model by using two DEMs were calibrated for a flood event (July 9, 2012). The roughness is considered as the calibration parameter. From comparison of input hydrograph at the upstream of the river and output hydrograph at the downstream of the river, the attenuation is obtained as 91% and 84% for the base DEM and scaled DEM, respectively. The time lag in hydrographs does not show any difference for two DEMs and it is obtained as 3 hours. Maximum flood extents differ for the two DEMs, larger flooded area is simulated from scaled DEM. The main difference is observed for the braided and meandering parts of the river. For the meandering part of the river, additional 1.82 106 m3 water (5% of the total volume) is calculated as the flooded volume simulated by using the scaled DEM. For the braided stream part 0.187 106 m3 more water is simulated as the flooded volume by the scaled DEM. The flood extent around the braided part of the river is 27.6 ha larger in the simulated flood map obtained from scaled DEM compared to the one obtained from base DEM. Around the meandering part of the river scaled DEM gave 59.8 ha more flooded area. The importance of correct topography of the braided and meandering part of the river in flood modelling and the uncertainty it brings to modelling are discussed in detail.

Threshold effects of flood duration on the vegetation and soils of the Upper Mississippi River floodplain, USA

USGS Publications Warehouse

De Jager, Nathan R.; Thomsen, Meredith; Yin, Yao

2012-01-01

Our results suggest that there is a threshold along the elevation gradient of this floodplain, corresponding with flood durations lasting ~40% of the growing season. At lower elevation sites, flooding exerts primary control over forest soils and vegetation, restricting the former to silt plus clay with higher organic matter and the latter to a few highly flood tolerant species. The existence of such thresholds have implications for management of floodplain soil nutrient dynamics and plant diversity under existing hydrologic regimes, more natural hydrologic regimes and more extreme hydrologic regimes that may result from climate change.

Simulations of the effects of U.S. Highway 231 and the proposed Montgomery outer loop on flooding in the Catoma Creek and Little Catoma Creek Basins near Montgomery, Alabama

USGS Publications Warehouse

Hedgecock, T. Scott

1999-01-01

A two-dimensional finite-element surface-water model was used to study the effects of U.S. Highway 231 and the proposed Montgomery Outer Loop on the water-surface elevations and flow distributions during flooding in the Catoma Creek and Little Catoma Creek Basins southeast of Montgomery, Montgomery County, Alabama. The effects of flooding were simulated for two scenarios--existing and proposed conditions--for the 100- and 500-year recurrence intervals. The first scenario was to model the existing bridge and highway configuration for U.S. Highway 231 and the existing ponds that lie just upstream from this crossing. The second scenario was to model the proposed bridge and highway configuration for the Montgomery Outer Loop and the Montgomery Loop Interchange at U.S. Highway 231 as well as the proposed modifications to the ponds upstream. Simulation of floodflow for Little Catoma Creek for the existing conditions at U.S. Highway 231 indicates that, for the 100-year flood, 54 percent of the flow (8,140 cubic feet per second) was conveyed by the northernmost bridge, 21 percent (3,130 cubic feet per second) by the middle bridge, and 25 percent (3,780 cubic feet per second) by the southernmost bridge. No overtopping of U.S. Highway 231 occurred. However, the levees of the catfish ponds immediately upstream from the crossing were completely overtopped. The average water- surface elevations for the 100-year flood at the upstream limits of the study reach for Catoma Creek and Little Catoma Creek were 216.9 and 218.3 feet, respectively. For the 500-year flood, the simulatin indicates that 51 percent of the flow (11,200 cubic feet per second) was conveyed by the northernmost bridge, 25 percent (5,480 cubic feet per second) by the middle bridge, and 24 percent (5,120 cubic feet per second) by the southernmost bridge. The average water0surface elevations for the 500-year flood at the upstream limits of the study reach for Catoma Creek and Little Catoma Creek were 218.2 and 219.5 feet, respectively. For the 500-year flood, no overtopping of U.S. Highway 231 occurred. Simulation of the 100-year floodflow for Little Catoma Creek for the proposed conditions indicates that, for the existing bridges on U.S. Highway 231, 54 percent of the flow (8,190 cubic feet per second) was conveyed by the northernmost bridge, 22 percent (3,350 cubic feet per second) by the middle bridge, and 24 percent (3,490 cubic feet per second) by the southernmost bridge. The two proposed relief bridges on the Montgomery Outer Loop upstream from the proposed remaining catfish ponds conveyed about 7,750 cubic feet per second (3,400 cubic feet per second for the west relief bridge and 4,350 cubic feet per second for the east relief bridge) with an average depth of flow of about 7 feet. The average water-surface elevation at the upstream limit of the study reach for Little Catoma Creek was 218.8 feet, which is about 0.5 foot higher than the average water-surface elevation for the existing conditions. For the 100-year flood, there was no overtopping of either U.S. Highway 231 or the Montgomery Outer Loop. However, the levees of the proposed remaining catfish ponds were completely overtopped. For the Montgomery Outer Loop crossing of Catoma Creek, simulation of the 100-year floodflow indicates that about 58 percent of the flow (14,100 cubic feet per second) was conveyed by the proposed main channel bridge and 42 percent (10,200 cubic feet per second) by the proposed relief bridge. The average water-surface elevation at the upstream limit of the study reach for Catoma Creek was 216.9 feet, which is the same as the water-surface elevation for the existing conditions. Results of model simulations for the 500-year flood for the proposed conditions indicate that there was no overtopping on either U.S. Highway 231 or the Montgomery Outer Loop. For the existing bridges on U.S. Highway 231, 42 percent of the flow (11,300 cubic feet per second) was conveyed by the northernmost bridge

Estimated flood-inundation mapping for the Lower Blue River in Kansas City, Missouri, 2003-2005

USGS Publications Warehouse

Kelly, Brian P.; Rydlund, Jr., Paul H.

2006-01-01

The U.S. Geological Survey, in cooperation with the city of Kansas City, Missouri, began a study in 2003 of the lower Blue River in Kansas City, Missouri, from Gregory Boulevard to the mouth at the Missouri River to determine the estimated extent of flood inundation in the Blue River valley from flooding on the lower Blue River and from Missouri River backwater. Much of the lower Blue River flood plain is covered by industrial development. Rapid development in the upper end of the watershed has increased the volume of runoff, and thus the discharge of flood events for the Blue River. Modifications to the channel of the Blue River began in late 1983 in response to the need for flood control. By 2004, the channel had been widened and straightened from the mouth to immediately downstream from Blue Parkway to convey a 30-year flood. A two-dimensional depth-averaged flow model was used to simulate flooding within a 2-mile study reach of the Blue River between 63rd Street and Blue Parkway. Hydraulic simulation of the study reach provided information for the design and performance of proposed hydraulic structures and channel improvements and for the production of estimated flood-inundation maps and maps representing an areal distribution of water velocity, both magnitude and direction. Flood profiles of the Blue River were developed between Gregory Boulevard and 63rd Street from stage elevations calculated from high water marks from the flood of May 19, 2004; between 63rd Street and Blue Parkway from two-dimensional hydraulic modeling conducted for this study; and between Blue Parkway and the mouth from an existing one-dimensional hydraulic model by the U.S. Army Corps of Engineers. Twelve inundation maps were produced at 2-foot intervals for Blue Parkway stage elevations from 750 to 772 feet. Each map is associated with National Weather Service flood-peak forecast locations at 63rd Street, Blue Parkway, Stadium Drive, U.S. Highway 40, 12th Street, and the Missouri River at the Hannibal railroad bridge in Kansas City. The National Weather Service issues peak-stage forecasts for these locations during times of flooding. Missouri River backwater inundation profiles were developed using interpolated Missouri River stage elevations at the mouth of the Blue River. Twelve backwater-inundation maps were produced at 2-foot intervals for the mouth of the Blue River from 730.9 to 752.9. To provide public access to the information presented in this report, a World Wide Web site (http://mo.water.usgs.gov/indep/kelly/blueriver/index.htm) was created that displays the results of two-dimensional modeling between 63rd Street and Blue Parkway, estimated flood-inundation maps, estimated backwater-inundation maps, and the latest gage heights and National Weather Service stage forecast for each forecast location within the study area. In addition, the full text of this report, all tables, and all plates are available for download at http://pubs.water.usgs.gov/sir2006-5089.

Global coastal flood hazard mapping

NASA Astrophysics Data System (ADS)

Eilander, Dirk; Winsemius, Hessel; Ward, Philip; Diaz Loaiza, Andres; Haag, Arjen; Verlaan, Martin; Luo, Tianyi

2017-04-01

Over 10% of the world's population lives in low-lying coastal areas (up to 10m elevation). Many of these areas are prone to flooding from tropical storm surges or extra-tropical high sea levels in combination with high tides. A 1 in 100 year extreme sea level is estimated to expose 270 million people and 13 trillion USD worth of assets to flooding. Coastal flood risk is expected to increase due to drivers such as ground subsidence, intensification of tropical and extra-tropical storms, sea level rise and socio-economic development. For better understanding of the hazard and drivers to global coastal flood risk, a globally consistent analysis of coastal flooding is required. In this contribution we present a comprehensive global coastal flood hazard mapping study. Coastal flooding is estimated using a modular inundation routine, based on a vegetation corrected SRTM elevation model and forced by extreme sea levels. Per tile, either a simple GIS inundation routine or a hydrodynamic model can be selected. The GIS inundation method projects extreme sea levels to land, taking into account physical obstructions and dampening of the surge level land inwards. For coastlines with steep slopes or where local dynamics play a minor role in flood behavior, this fast GIS method can be applied. Extreme sea levels are derived from the Global Tide and Surge Reanalysis (GTSR) dataset. Future sea level projections are based on probabilistic sea level rise for RCP 4.5 and RCP 8.5 scenarios. The approach is validated against observed flood extents from ground and satellite observations. The results will be made available through the online Aqueduct Global Flood Risk Analyzer of the World Resources Institute.

78 FR 8416 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-06

... the communities listed below. These modified BFEs will be used to calculate flood insurance premium... management requirements of the NFIP and also are used to calculate the appropriate flood insurance premium... indicated on the following table and revise the Flood Insurance Rate Maps (FIRMs) in effect for the listed...

77 FR 76915 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-31

... the communities listed below. These modified BFEs will be used to calculate flood insurance premium... requirements of the NFIP and also are used to calculate the appropriate flood insurance premium rates for new... indicated on the following table and revise the Flood Insurance Rate Maps (FIRMs) in effect for the listed...

Maine coastal storm and flood of February 2, 1976

USGS Publications Warehouse

Morrill, Richard Arthur; Chin, Edwin H.; Richardson, W.S.

1979-01-01

A business section of Bangor, Maine, was flooded with 12 feet (3.7 m) of water on February 2, 1976. The water surface elevation reached 17.46 feet (5.32 m) above national geodetic vertical datum of 1929 (NGVD), approximately 10.5 feet (3.2 m) above the predicted astronomical tide at Bangor. The unusually high water resulted from a tidal storm surge caused by prolonged strong, south-southeasterly winds which occurred near the time of astronomical high tide. Winds exceeded 64 knots off the New England coast. The resulting flood was the third highest since 1846 and is the first documented tidal flood at Bangor. This report documents the meteorological and hydrologic conditions associated with the flooding and also contains a brief description of storm damage from Eastport to Brunswick, Maine. Included are flood elevations in the city of Bangor and along the coast of Maine east of the Kennebec River. (Kosco-USGS)

Variability in eddy sandbar dynamics during two decades of controlled flooding of the Colorado River in the Grand Canyon

USGS Publications Warehouse

Mueller, Erich R.; Grams, Paul E.; Hazel, Joseph E.; Schmidt, John C.

2018-01-01

Sandbars are iconic features of the Colorado River in the Grand Canyon, Arizona, U.S.A. Following completion of Glen Canyon Dam in 1963, sediment deficit conditions caused erosion of eddy sandbars throughout much of the 360 km study reach downstream from the dam. Controlled floods in 1996, 2004, and 2008 demonstrated that sand on the channel bed could be redistributed to higher elevations, and that floods timed to follow tributary sediment inputs would increase suspended sand concentrations during floods. Since 2012, a new management protocol has resulted in four controlled floods timed to follow large inputs of sand from a major tributary. Monitoring of 44 downstream eddy sandbars, initiated in 1990, shows that each controlled flood deposited significant amounts of sand and increased the size of subaerial sandbars. However, the magnitude of sandbar deposition varied from eddy to eddy, even over relatively short distances where main-stem suspended sediment concentrations were similar. Here, we characterize spatial and temporal trends in sandbar volume and site-scale (i.e., individual eddy) sediment storage as a function of flow, channel, and vegetation characteristics that reflect the reach-scale (i.e., kilometer-scale) hydraulic environment. We grouped the long-term monitoring sites based on geomorphic setting and used a principal component analysis (PCA) to correlate differences in sandbar behavior to changes in reach-scale geomorphic metrics. Sites in narrow reaches are less-vegetated, stage changes markedly with discharge, sandbars tend to remain dynamic, and sand storage change dominantly occurs in the eddy compared to the main channel. In wider reaches, where stage-change during floods may be half that of narrow sites, sandbars are more likely to be stabilized by vegetation, and floods tend to aggrade the vegetated sandbar surfaces. In these locations, deposition during controlled floods is more akin to floodplain sedimentation, and the elevation of sandbar surfaces increases with successive floods. Because many sandbars are intermediate to the end members described above, high-elevation bar surfaces stabilized by vegetation often have a more dynamic unvegetated sandbar on the channel-ward margin that aggrades and erodes in response to controlled flood cycles. Ultimately, controlled floods have been effective at increasing averaged sandbar volumes, and, while bar deposition during floods decreases through time where vegetation has stabilized sandbars, future controlled floods are likely to continue to result in deposition in a majority of the river corridor.

Fifty-year flood-inundation maps for La Lima, Honduras

USGS Publications Warehouse

Mastin, Mark C.; Olsen, T.D.

2002-01-01

After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of La Lima that would be inundated by Rio Chamelecon with a discharge of 500 cubic meters per second, the approximate capacity of the river channel through the city of La Lima. The 50-year flood (2,400 cubic meters per second), the original design flow to be mapped, would inundate the entire area surveyed for this municipality. Because water-surface elevations of the 50-year flood could not be mapped properly without substantially expanding the area of the survey, the available data were used instead to estimate the channel capacity of Rio Chamelecon in La Lima by trial-and-error runs of different flows in a numerical model and to estimate the increase in height of levees needed to contain flows of 1,000 and 2,400 cubic meters per second. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of La Lima as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for various discharges on Rio Chamelecon at La Lima were determined using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area and ground surveys at three bridges. Top-of-levee or top-of-channel-bank elevations and locations at the cross sections were critical to estimating the channel capacity of Rio Chamelecon. These elevations and locations are provided along with the water-surface elevations for the 500-cubic-meter-per-second flow of Rio Chamelecon. Also, water-surface elevations of the 1,000 and 2,400 cubic-meter-per-second flows are provided, assuming that the existing levees are raised to contained the flows.

1997 flood tracking chart for the Red River of the North basin

USGS Publications Warehouse

Wiche, G.J.; Martin, C.R.; Albright, L.L.; Wald, Geraldine B.

1997-01-01

The flood tracking chart for the Red River of the North Basin can be used by local citizens and emergency response personnel to determine the latest river stage. By comparing the current stage (water-surface elevation above some datum) and predicted flood crest to the recorded peak stages of previous floods, emergency response personnel and residents can make informed decisions concerning the threat to life and property. The flood tracking chart shows a map of the basin with the location of major real-time streamflow-gaging stations in the basin. Click on a station in the map or in the list below the map. Streamflow and stage information for the last 7 days, current stage relative to recorded peak stages, and streamflow for the previous 18 months are provided in graphic form, along with information such as station location and length of record. The National Weather Service has direct access to all information collected by the USGS for use in their forecasting models and routinely broadcasts the forecast information to the news media and on shortwave radio. The radio frequencies are 162.400 MHz (megahertz) in Petersburg, N. Dak., and Detroit Lakes, Minn.; 162.425 MHz in Webster, N. Dak., and Bemidji, Minn.; 162.450 MHz in Roosevelt, Minn.; 162.475 MHz in Grand Forks and Amenia, N. Dak.; and 162.550 MHz in Thief River Falls, Minn. To use the flood tracking chart for a particular property, determine the approximate elevation of the threatened property and the elevation of the gaging station that is closest to the threatened property. For example, most people in Grand Forks, N. Dak., probably will use the Red River of the North at Grand Forks station. Record the flood elevation for the gaging station. Compare the flood elevation to the elevation of the property to immediately know if the property has an impending threat of flooding. One must be cautioned by the fact that the surface of flowing water is not flat but has a slope. Therefore, the water-surface elevation near a threatened property might not be the same as the river stages at the gaging stations. The network of river-gaging stations in the Red River of the North Basin is operated by the USGS in cooperation with the U.S. Army Corps of Engineers, the North Dakota State Water Commission, the Minnesota Department of Natural Resources, the Southeast Cass Water Resources District, the Cass County Joint Water Resource District, the Red River Joint Water Resource Board, and the Red River Watershed Management Board. For more information about USGS programs in North Dakota, contact the District Chief, U.S. Geological Survey, North Dakota District, at (701) 250-7400.

Comparison of floods non-stationarity detection methods: an Austrian case study

NASA Astrophysics Data System (ADS)

Salinas, Jose Luis; Viglione, Alberto; Blöschl, Günter

2016-04-01

Non-stationarities in flood regimes have a huge impact in any mid and long term flood management strategy. In particular the estimation of design floods is very sensitive to any kind of flood non-stationarity, as they should be linked to a return period, concept that can be ill defined in a non-stationary context. Therefore it is crucial when analyzing existent flood time series to detect and, where possible, attribute flood non-stationarities to changing hydroclimatic and land-use processes. This works presents the preliminary results of applying different non-stationarity detection methods on annual peak discharges time series over more than 400 gauging stations in Austria. The kind of non-stationarities analyzed include trends (linear and non-linear), breakpoints, clustering beyond stochastic randomness, and detection of flood rich/flood poor periods. Austria presents a large variety of landscapes, elevations and climates that allow us to interpret the spatial patterns obtained with the non-stationarity detection methods in terms of the dominant flood generation mechanisms.

A spatial assessment framework for evaluating flood risk under extreme climates.

PubMed

Chen, Yun; Liu, Rui; Barrett, Damian; Gao, Lei; Zhou, Mingwei; Renzullo, Luigi; Emelyanova, Irina

2015-12-15

Australian coal mines have been facing a major challenge of increasing risk of flooding caused by intensive rainfall events in recent years. In light of growing climate change concerns and the predicted escalation of flooding, estimating flood inundation risk becomes essential for understanding sustainable mine water management in the Australian mining sector. This research develops a spatial multi-criteria decision making prototype for the evaluation of flooding risk at a regional scale using the Bowen Basin and its surroundings in Queensland as a case study. Spatial gridded data, including climate, hydrology, topography, vegetation and soils, were collected and processed in ArcGIS. Several indices were derived based on time series of observations and spatial modeling taking account of extreme rainfall, evapotranspiration, stream flow, potential soil water retention, elevation and slope generated from a digital elevation model (DEM), as well as drainage density and proximity extracted from a river network. These spatial indices were weighted using the analytical hierarchy process (AHP) and integrated in an AHP-based suitability assessment (AHP-SA) model under the spatial risk evaluation framework. A regional flooding risk map was delineated to represent likely impacts of criterion indices at different risk levels, which was verified using the maximum inundation extent detectable by a time series of remote sensing imagery. The result provides baseline information to help Bowen Basin coal mines identify and assess flooding risk when making adaptation strategies and implementing mitigation measures in future. The framework and methodology developed in this research offers the Australian mining industry, and social and environmental studies around the world, an effective way to produce reliable assessment on flood risk for managing uncertainty in water availability under climate change. Copyright © 2015. Published by Elsevier B.V.

Prediction of River Flooding using Geospatial and Statistical Analysis in New York, USA and Kent, UK

NASA Astrophysics Data System (ADS)

Marsellos, A.; Tsakiri, K.; Smith, M.

2014-12-01

Flooding in the rivers normally occurs during periods of excessive precipitation (i.e. New York, USA; Kent, UK) or ice jams during the winter period (New York, USA). For the prediction and mapping of the river flooding, it is necessary to evaluate the spatial distribution of the water (volume) in the river as well as study the interaction between the climatic and hydrological variables. Two study areas have been analyzed; one in Mohawk River, New York and one in Kent, United Kingdom (UK). A high resolution Digital Elevation Model (DEM) of the Mohawk River, New York has been used for a GIS flooding simulation to determine the maximum elevation value of the water that cannot continue to be restricted in the trunk stream and as a result flooding in the river may be triggered. The Flooding Trigger Level (FTL) is determined by incremental volumetric and surface calculations from Triangulated Irregular Network (TIN) with the use of GIS software and LiDAR data. The prediction of flooding in the river can also be improved by the statistical analysis of the hydrological and climatic variables in Mohawk River and Kent, UK. A methodology of time series analysis has been applied for the decomposition of the hydrological (water flow and ground water data) and climatic data in both locations. The KZ (Kolmogorov-Zurbenko) filter is used for the decomposition of the time series into the long, seasonal, and short term components. The explanation of the long term component of the water flow using the climatic variables has been improved up to 90% for both locations. Similar analysis has been performed for the prediction of the seasonal and short term component. This methodology can be applied for flooding of the rivers in multiple sites.

Use of Light Detection and Ranging (LiDAR) to Obtain High-Resolution Elevation Data for Sussex County, Delaware

USGS Publications Warehouse

Barlow, Roger A.; Nardi, Mark R.; Reyes, Betzaida

2008-01-01

Sussex County, Delaware, occupies a 938-square-mile area of low relief near sea level in the Atlantic Coastal Plain. The county is bounded on the east by the Delaware Bay and the Atlantic Ocean, including a barrier-island system, and inland bays that provide habitat for valuable living resources. Eastern Sussex County is an area of rapid population growth with a long-established beach-resort community, where land elevation is a key factor in determining areas that are appropriate for development. Of concern to State and local planners are evacuation routes inland to escape flooding from severe coastal storms, as most major transportation routes traverse areas of low elevation that are subject to inundation. The western half of the county is typically rural in character, and land use is largely agricultural with some scattered forest land cover. Western Sussex County has several low-relief river flood-prone areas, where accurate high-resolution elevation data are needed for Federal Emergency Management Agency (FEMA) Digital Flood Insurance Rate Map (DFIRM) studies. This fact sheet describes the methods and techniques used to collect and process LiDAR elevation data, the generation of the digital elevation model (DEM) and the 2-foot contours, and the quality-assurance procedures and results. It indicates where to view metadata on the data sets and where to acquire bare-earth mass points, DEM data, and contour data.

Re-establishing marshes can return carbon sink functions to a current carbon source in the Sacramento-San Joaquin Delta of California, USA

USGS Publications Warehouse

Miller, Robin L.; Fujii, Roger; Schmidt, Paul E.

2011-01-01

The Sacramento-San Joaquin Delta in California was an historic, vast inland freshwater wetland, where organic soils almost 20 meters deep formed over the last several millennia as the land surface elevation of marshes kept pace with sea level rise. A system of levees and pumps were installed in the late 1800s and early 1900s to drain the land for agricultural use. Since then, land surface has subsided more than 7 meters below sea level in some areas as organic soils have been lost to aerobic decomposition. As land surface elevations decrease, costs for levee maintenance and repair increase, as do the risks of flooding. Wetland restoration can be a way to mitigate subsidence by re-creating the environment in which the organic soils developed. A preliminary study of the effect of hydrologic regime on carbon cycling conducted on Twitchell Island during the mid-1990s showed that continuous, shallow flooding allowing for the growth of emergent marsh vegetation re-created a wetland environment where carbon preservation occurred. Under these conditions annual plant biomass carbon inputs were high, and microbial decomposition was reduced. Based on this preliminary study, the U.S. Geological Survey re-established permanently flooded wetlands in fall 1997, with shallow water depths of 25 and 55 centimeters, to investigate the potential to reverse subsidence of delta islands by preserving and accumulating organic substrates over time. Ten years after flooding, elevation gains from organic matter accumulation in areas of emergent marsh vegetation ranged from almost 30 to 60 centimeters, with average annual carbon storage rates approximating 1 kg/m2, while areas without emergent vegetation cover showed no significant change in elevation. Differences in accretion rates within areas of emergent marsh vegetation appeared to result from temporal and spatial variability in hydrologic factors and decomposition rates in the wetlands rather than variability in primary production. Decomposition rates were related to differences in hydrologic conditions, including water temperature, pH, dissolved oxygen concentration, and availability of alternate electron acceptors. The study showed that marsh re-establishment with permanent, low energy, shallow flooding can limit oxidation of organic soils, thus, effectively turning subsiding land from atmospheric carbon sources to carbon sinks, and at the same time reducing flood vulnerability.

Changing tidal hydrodynamics during different stages of eco-geomorphological development of a tidal marsh: A numerical modeling study

NASA Astrophysics Data System (ADS)

Stark, J.; Meire, P.; Temmerman, S.

2017-03-01

The eco-geomorphological development of tidal marshes, from initially low-elevated bare tidal flats up to a high-elevated marsh and its typical network of channels and creeks, induces long-term changes in tidal hydrodynamics in a marsh, which will have feedback effects on the marsh development. We use a two-dimensional hydrodynamic model of the Saeftinghe marsh (Netherlands) to study tidal hydrodynamics, and tidal asymmetry in particular, for model scenarios with different input bathymetries and vegetation coverages that represent different stages of eco-geomorphological marsh development, from a low elevation stage with low vegetation coverage to a high and fully vegetated marsh platform. Tidal asymmetry is quantified along a 4 km marsh channel by (1) the difference in peak flood and peak ebb velocities, (2) the ratio between duration of the rising tide and the falling tide and (3) the time-integrated dimensionless bed shear stress during flood and ebb. Although spatial variations in tidal asymmetry are large and the different indicators for tidal asymmetry do not always respond similarly to eco-geomorphological changes, some general trends can be obtained. Flood-dominance prevails during the initial bare stage of a low-lying tidal flat. Vegetation establishment and platform expansion lead to marsh-scale flow concentration to the bare channels, causing an increase in tidal prism in the channels along with a less flood-dominant asymmetry of the horizontal tide. The decrease in flood-dominance continues as the platform grows vertically and the sediment-demand of the platform decreases. However, when the platform elevation gets sufficiently high in the tidal frame and part of the spring-neap cycle is confined to the channels, the discharge in the channels decreases and tidal asymmetry becomes more flood-dominant again, indicating an infilling of the marsh channels. Furthermore, model results suggest that hydro-morphodynamic feedbacks based on tidal prism to channel cross-sectional area relationships keep the marsh channels from filling in completely by enhancing ebb-dominance as long as the tidal volume and flow velocities remain sufficiently high. Overall, this study increases insight into the hydro-morphodynamic interactions between tidal flow and marsh geomorphology during various stages of eco-geomorphological development of marshes and marsh channels in particular.

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.

Documentation and hydrologic analysis of Hurricane Sandy in New Jersey, October 29–30, 2012

USGS Publications Warehouse

Suro, Thomas P.; Deetz, Anna; Hearn, Paul

2016-11-17

In 2012, a late season tropical depression developed into a tropical storm and later a hurricane. The hurricane, named “Hurricane Sandy,” gained strength to a Category 3 storm on October 25, 2012, and underwent several transitions on its approach to the mid-Atlantic region of the eastern coast of the United States. By October 28, 2012, Hurricane Sandy had strengthened into the largest hurricane ever recorded in the North Atlantic and was tracking parallel to the east coast of United States, heading toward New Jersey. On October 29, 2012, the storm turned west-northwest and made landfall near Atlantic City, N.J. The high winds and wind-driven storm surge caused massive damage along the entire coastline of New Jersey. Millions of people were left without power or communication networks. Many homes were completely destroyed. Sand dunes were eroded, and the barrier island at Mantoloking was breached, connecting the ocean with Barnegat Bay.Several days before the storm made landfall in New Jersey, the U.S. Geological Survey (USGS) made a decision to deploy a temporary network of storm-tide sensors and barometric pressure sensors from Virginia to Maine to supplement the existing USGS and National Oceanic and Atmospheric Administration (NOAA) networks of permanent tide monitoring stations. After the storm made landfall, the USGS conducted a sensor data recovery and high-water-mark collection campaign in cooperation with the Federal Emergency Management Agency (FEMA).Peak storm-tide elevations documented at USGS tide gages, tidal crest-stage gages, temporary storm sensor locations, and high-water-mark sites indicate the area from southern Monmouth County, N.J., north through Raritan Bay, N.J., had the highest peak storm-tide elevations during this storm. The USGS tide gages at Raritan River at South Amboy and Raritan Bay at Keansburg, part of the New Jersey Tide Telemetry System, each recorded peak storm-tide elevations of greater than 13 feet (ft)—more than 5 ft higher than the previously recorded period-of-record maximum. A comparison of peak storm-tide elevations to preliminary FEMA Coastal Flood Insurance Study flood elevations indicated that these areas experienced the highest recurrence intervals along the coast of New Jersey. Analysis showed peak storm-tide elevations exceeded the 100-year FEMA flood elevations in many parts of Middlesex, Union, Essex, Hudson, and Bergen Counties, and peak storm-tide elevations at many locations in Monmouth County exceeded the 500-year recurrence interval.A level 1 HAZUS (HAZards United States) analysis was done for the counties in New Jersey affected by flooding to estimate total building stock losses. The aggregated total building stock losses estimated by HAZUS for New Jersey, on the basis of the final inundation verified by USGS high-water marks, was almost $19 billion. A comparison of Hurricane Sandy with historic coastal storms showed that peak storm-tide elevations associated with Hurricane Sandy exceeded most of the previously documented elevations associated with the storms of December 1992, March 1962, September 1960, and September 1944 at many coastal communities in New Jersey. This scientific investigation report was prepared in cooperation with FEMA to document flood processes and flood damages resulting from this storm and to assist in future flood mitigation actions in New Jersey.

Hydraulic analysis, Mad River at State Highway 41, Springfield, Ohio

USGS Publications Warehouse

Mayo, Ronald I.

1977-01-01

A hydraulic analysis of the lad River in a reach at Springfield, Ohio was made to determine the effects of relocating State Highway 41 in 1S76. The main channel was cleaned by dredging in the vicinity cf the new highway bridge and at the Detroit, Toledo and Ironton Railway bridge upstream. The new highway was placed on a high fill with relief structures for flood plain drainage consisting of a 12-foot corrugated metal pipe culvert and a bridge opening to accommodate the Detroit, Toledo and Ironton Railway and a property access road. The effect of the new highway embankment on drainage from the flood plain was requested. Also requested was the effect that might be expected on the elevation of flood waters above the new highway embankment if the access road through the new highway embankment were raised.The study indicates that the improvement in the capacity of the main channel to carry water was such that, up to a discharge equivalent to a 25-year frequency flood, the water-surface elevation in the reach upstream from the Detroit, Toledo and Ironton Railway bridge would be about 0.6 foot lower than under conditions prior to the construction on State Highway 41. Diversion through the Mad River left bank levee break above the Detroit, Toledo and Ironton Railway bridge to the flood Flain would be decreased about one-half in terms of rate of discharge in cubic feet per second. The maximum difference in elevation cf the flood water between the upstream and downstream side of the new State Highway 41 embankment would be about 0.2 foot, with an additional 0.4 foot to be expected if the access road were raised 1.5 feet.

Public Use of Online Hydrology Information for Harris County and Houston, Texas, during Hurricane Harvey and Suggested Improvement for Future Flood Events

NASA Astrophysics Data System (ADS)

Lilly, M. R.; Feditova, A.; Levine, K.; Giardino, J. R.

2017-12-01

The Harris County Flood Control District has an impressive amount of information available for the public related to flood management and response. During Hurricane Harvey, this information was used by the authors to help address daily questions from family and friends living in the Houston area. Common near-real-time reporting data included precipitation and water levels. Maps included locations of data stations, stream or bayou conditions (in bank, out of bank) and watershed or drainage boundaries. In general, the data station reporting and online information was updating well throughout the hurricane and post-flooding period. Only a few of the data reporting stations had problems with water level sensor measurements. The overall information was helpful to hydrologists and floodplain managers. The online information could not easily answer all common questions residents may have during a flood event. Some of the more common questions were how to use the water-level information to know the potential extent of flooding and relative location of flooding to the location of residents. To help address the questions raised during the flooding on how to use the available water level data, we used Google Earth to get lot and intersection locations to help show the relative differences between nearby water-level stations and residences of interest. The reported resolution of the Google Earth elevation data is 1-foot. To help confirm the use of this data, we compared Google Earth approximate elevations with reported Harris County Floodplain Reference Mark individual reports. This method helped verify we could use the Google Earth information for approximate comparisons. We also faced questions on what routes to take if evacuation was needed, and where to go to get to higher ground elevations. Google Earth again provided a helpful and easy to use interface to look at road and intersection elevations and develop suggested routes for family and friends to take to avoid low areas that may be subject to flooding. These and other recommendations that helped answer common questions by residents reacting to the hurricane and subsequent flooding conditions are summarized with examples.

Forecasted Flood Depth Grids Providing Early Situational Awareness to FEMA during the 2017 Atlantic Hurricane Season

NASA Astrophysics Data System (ADS)

Jones, M.; Longenecker, H. E., III

2017-12-01

The 2017 hurricane season brought the unprecedented landfall of three Category 4 hurricanes (Harvey, Irma and Maria). FEMA is responsible for coordinating the federal response and recovery efforts for large disasters such as these. FEMA depends on timely and accurate depth grids to estimate hazard exposure, model damage assessments, plan flight paths for imagery acquisition, and prioritize response efforts. In order to produce riverine or coastal depth grids based on observed flooding, the methodology requires peak crest water levels at stream gauges, tide gauges, high water marks, and best-available elevation data. Because peak crest data isn't available until the apex of a flooding event and high water marks may take up to several weeks for field teams to collect for a large-scale flooding event, final observed depth grids are not available to FEMA until several days after a flood has begun to subside. Within the last decade NOAA's National Weather Service (NWS) has implemented the Advanced Hydrologic Prediction Service (AHPS), a web-based suite of accurate forecast products that provide hydrograph forecasts at over 3,500 stream gauge locations across the United States. These forecasts have been newly implemented into an automated depth grid script tool, using predicted instead of observed water levels, allowing FEMA access to flood hazard information up to 3 days prior to a flooding event. Water depths are calculated from the AHPS predicted flood stages and are interpolated at 100m spacing along NHD hydrolines within the basin of interest. A water surface elevation raster is generated from these water depths using an Inverse Distance Weighted interpolation. Then, elevation (USGS NED 30m) is subtracted from the water surface elevation raster so that the remaining values represent the depth of predicted flooding above the ground surface. This automated process requires minimal user input and produced forecasted depth grids that were comparable to post-event observed depth grids and remote sensing-derived flood extents for the 2017 hurricane season. These newly available forecasted models were used for pre-event response planning and early estimated hazard exposure counts, allowing FEMA to plan for and stand up operations several days sooner than previously possible.

44 CFR 65.5 - Revision to special hazard area boundaries with no change to base flood elevation determinations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... flood elevation. Scientific and technical information to support a request to gain exclusion from an... hazard. (4) Written assurance by the participating community that they have complied with the appropriate... participating community has determined that the land and any existing or proposed structures to be removed from...

11. VIEW OF FLOOD GATE FOR THE PRESSURE CULVERT AND ...

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

11. VIEW OF FLOOD GATE FOR THE PRESSURE CULVERT AND THE SOUTH AND EAST ELEVATIONS, LOOKING NORTHWEST. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

Flood-inundation maps for the Driftwood River and Sugar Creek near Edinburgh, Indiana

USGS Publications Warehouse

Fowler, Kathleen K.; Kim, Moon H.; Menke, Chad D.

2012-01-01

Digital flood-inundation maps for an 11.2 mile reach of the Driftwood River and a 5.2 mile reach of Sugar Creek, both near Edinburgh, Indiana, were created by the U.S. Geological Survey (USGS) in cooperation with the Camp Atterbury Joint Maneuver Training Center, Edinburgh, Indiana. The inundation maps, which can be accessed through the USGS Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/, depict estimates of the areal extent of flooding corresponding to selected water levels (stages) at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. Current conditions at the USGS streamgage in Indiana may be obtained on the Internet at http://waterdata.usgs.gov/in/nwis/current/?type=flow. In addition, the information has been provided to the National Weather Service (NWS) for incorporation into their Advanced Hydrologic Prediction Service (AHPS) flood warning system at http://water.weather.gov/ahps/. The NWS forecasts flood hydrographs at many places that are often collocated at USGS streamgages. That forecasted peak-stage information, also available on the Internet, may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. For this study, flood profiles were computed for the stream reaches by means of a one-dimensional step-backwater model. The model was calibrated using the most current stage-discharge relations at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. The hydraulic model was then used to determine elevations throughout the study reaches for nine water-surface profiles for flood stages at 1-ft intervals referenced to the streamgage datum and ranging from bankfull to nearly the highest recorded water level at the USGS streamgage 03363000 Driftwood River near Edinburgh, Ind. The simulated water-surface profiles were then combined with a geospatial digital elevation model (derived from Light Detection and Ranging (LiDAR) data) in order to delineate the area flooded at each water level. The availability of these maps along with real-time information available online regarding current stage from USGS streamgages and forecasted stream stages from the NWS provide emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures as well as for post flood recovery efforts.

A Study on the Assessment of Multi-Factors Affecting Urban Floods Using Satellite Image: A Case Study in Nakdong Basin, S. Korea

NASA Astrophysics Data System (ADS)

Kwak, Youngjoo; Kondoh, Akihiko

2010-05-01

Floods are also related to the changes in social economic conditions and land use. Recently, floods increased due to rapid urbanization and human activity in the lowland. Therefore, integrated management of total basin system is necessary to get the secure society. Typhoon ‘Rusa’ swept through eastern and southern parts of South Korea in the 2002. This pity experience gave us valuable knowledge that could be used to mitigate the future flood hazards. The purpose of this study is to construct the digital maps of the multi-factors related to urban flood concerning geomorphologic characteristics, land cover, and surface wetness. Parameters particularly consider geomorphologic functional unit, geomorphologic parameters derived from DEM (digital elevation model), and land use. The research area is Nakdong River Basin in S. Korea. As a result of preliminary analysis for Pusan area, the vulnerability map and the flood-prone areas can be extracted by applying spatial analysis on GIS (geographic information system).

Impact of sea level rise on tide gate function.

PubMed

Walsh, Sean; Miskewitz, Robert

2013-01-01

Sea level rise resulting from climate change and land subsidence is expected to severely impact the duration and associated damage resulting from flooding events in tidal communities. These communities must continuously invest resources for the maintenance of existing structures and installation of new flood prevention infrastructure. Tide gates are a common flood prevention structure for low-lying communities in the tidal zone. Tide gates close during incoming tides to prevent inundation from downstream water propagating inland and open during outgoing tides to drain upland areas. Higher downstream mean sea level elevations reduce the effectiveness of tide gates by impacting the hydraulics of the system. This project developed a HEC-RAS and HEC-HMS model of an existing tide gate structure and its upland drainage area in the New Jersey Meadowlands to simulate the impact of rising mean sea level elevations on the tide gate's ability to prevent upstream flooding. Model predictions indicate that sea level rise will reduce the tide gate effectiveness resulting in longer lasting and deeper flood events. The results indicate that there is a critical point in the sea level elevation for this local area, beyond which flooding scenarios become dramatically worse and would have a significantly negative impact on the standard of living and ability to do business in one of the most densely populated areas of America.

Revision to flood hazard evaluation for the Savannah River Site

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

Buckley, R.; Werth, D.

Requirements for the Natural Phenomena Hazard (NPH) mitigation for new and existing Department of Energy (DOE) facilities are outlined in DOE Order 420.1. This report examines the hazards posed by potential flooding and represents an update to two previous reports. The facility-specific probabilistic flood hazard curve is defined as the water elevation for each annual probability of precipitation occurrence (or inversely, the return period in years). New design hyetographs for both 6-hr and 24-hr precipitation distributions were used in conjunction with hydrological models of various basins within the Savannah River Site (SRS). For numerous locations of interest, peak flow dischargemore » and flood water elevation were determined. In all cases, the probability of flooding of these facilities for a 100,000 year precipitation event is negligible.« less

77 FR 56669 - Proposed Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-13

...Comments are requested on proposed flood hazard determinations, which may include additions or modifications of any Base Flood Elevation (BFE), base flood depth, Special Flood Hazard Area (SFHA) boundary or zone designation, or regulatory floodway on the Flood Insurance Rate Maps (FIRMs), and where applicable, in the supporting Flood Insurance Study (FIS) reports for the communities listed in the table below. The purpose of this notice is to seek general information and comment regarding the preliminary FIRM, and where applicable, the FIS report that the Federal Emergency Management Agency (FEMA) has provided to the affected communities. The FIRM and FIS report are the basis of the floodplain management measures that the community is required either to adopt or to show evidence of having in effect in order to qualify or remain qualified for participation in the National Flood Insurance Program (NFIP). In addition, the FIRM and FIS report, once effective, will be used by insurance agents and others to calculate appropriate flood insurance premium rates for new buildings and the contents of those buildings.

Identification and delineation of areas flood hazard using high accuracy of DEM data

NASA Astrophysics Data System (ADS)

Riadi, B.; Barus, B.; Widiatmaka; Yanuar, M. J. P.; Pramudya, B.

2018-05-01

Flood incidents that often occur in Karawang regency need to be mitigated. These expectations exist on technologies that can predict, anticipate and reduce disaster risks. Flood modeling techniques using Digital Elevation Model (DEM) data can be applied in mitigation activities. High accuracy DEM data used in modeling, will result in better flooding flood models. The result of high accuracy DEM data processing will yield information about surface morphology which can be used to identify indication of flood hazard area. The purpose of this study was to identify and describe flood hazard areas by identifying wetland areas using DEM data and Landsat-8 images. TerraSAR-X high-resolution data is used to detect wetlands from landscapes, while land cover is identified by Landsat image data. The Topography Wetness Index (TWI) method is used to detect and identify wetland areas with basic DEM data, while for land cover analysis using Tasseled Cap Transformation (TCT) method. The result of TWI modeling yields information about potential land of flood. Overlay TWI map with land cover map that produces information that in Karawang regency the most vulnerable areas occur flooding in rice fields. The spatial accuracy of the flood hazard area in this study was 87%.

Dependence of flood risk perceptions on socioeconomic and objective risk factors

NASA Astrophysics Data System (ADS)

Botzen, W. J. W.; Aerts, J. C. J. H.; van den Bergh, J. C. J. M.

2009-10-01

This study examines flood risk perceptions of individuals in the Netherlands using a survey of approximately 1000 homeowners. Perceptions of a range of aspects of flood risk are elicited. Various statistical models are used to estimate the influence of socioeconomic and geographical characteristics, personal experience with flooding, knowledge of flood threats, and individual risk attitudes on shaping risk belief. The study shows that in general, perceptions of flood risk are low. An analysis of the factors determining risk perceptions provides four main insights relevant for policy makers and insurers. First, differences in expected risk are consistently related to actual risk levels, since individuals in the vicinity of a main river and low-lying areas generally have elevated risk perceptions. Second, individuals in areas unprotected by dikes tend to underestimate their risk of flooding. Third, individuals with little knowledge of the causes of flood events have lower perceptions of flood risk. Fourth, there is some evidence that older and more highly educated individuals have a lower flood risk perception. The findings indicate that increasing knowledge of citizens about the causes of flooding may increase flood risk awareness. It is especially important to target individuals who live in areas unprotected by dike infrastructure, since they tend to be unaware of or ignore the high risk exposure faced.

A Study on Integrated Community Based Flood Mitigation with Remote Sensing Technique in Kota Bharu, Kelantan

NASA Astrophysics Data System (ADS)

'Ainullotfi, A. A.; Ibrahim, A. L.; Masron, T.

2014-02-01

This study is conducted to establish a community based flood management system that is integrated with remote sensing technique. To understand local knowledge, the demographic of the local society is obtained by using the survey approach. The local authorities are approached first to obtain information regarding the society in the study areas such as the population, the gender and the tabulation of settlement. The information about age, religion, ethnic, occupation, years of experience facing flood in the area, are recorded to understand more on how the local knowledge emerges. Then geographic data is obtained such as rainfall data, land use, land elevation, river discharge data. This information is used to establish a hydrological model of flood in the study area. Analysis were made from the survey approach to understand the pattern of society and how they react to floods while the analysis of geographic data is used to analyse the water extent and damage done by the flood. The final result of this research is to produce a flood mitigation method with a community based framework in the state of Kelantan. With the flood mitigation that involves the community's understanding towards flood also the techniques to forecast heavy rainfall and flood occurrence using remote sensing, it is hope that it could reduce the casualties and damage that might cause to the society and infrastructures in the study area.

The impact of bathymetry input on flood simulations

NASA Astrophysics Data System (ADS)

Khanam, M.; Cohen, S.

2017-12-01

Flood prediction and mitigation systems are inevitable for improving public safety and community resilience all over the worldwide. Hydraulic simulations of flood events are becoming an increasingly efficient tool for studying and predicting flood events and susceptibility. A consistent limitation of hydraulic simulations of riverine dynamics is the lack of information about river bathymetry as most terrain data record water surface elevation. The impact of this limitation on the accuracy on hydraulic simulations of flood has not been well studies over a large range of flood magnitude and modeling frameworks. Advancing our understanding of this topic is timely given emerging national and global efforts for developing automated flood predictions systems (e.g. NOAA National Water Center). Here we study the response of flood simulation to the incorporation of different bathymetry and floodplain surveillance source. Different hydraulic models are compared, Mike-Flood, a 2D hydrodynamic model, and GSSHA, a hydrology/hydraulics model. We test a hypothesis that the impact of inclusion/exclusion of bathymetry data on hydraulic model results will vary in its magnitude as a function of river size. This will allow researcher and stake holders more accurate predictions of flood events providing useful information that will help local communities in a vulnerable flood zone to mitigate flood hazards. Also, it will help to evaluate the accuracy and efficiency of different modeling frameworks and gage their dependency on detailed bathymetry input data.

75 FR 68710 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-09

... downstream of Ager Road. California Unincorporated Panther Creek Shallow flooding 1, 3 County. flooding). Squaw Valley Creek and McCloud River Railroad. California Unincorporated Panther Creek Approximately 2... Unincorporated Panther Creek Immediately south 2 Areas of Siskiyou Overflow (shallow of and adjacent County...

77 FR 67324 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-09

...). Specifically, it addresses the flooding sources Big Run, Little Loyalsock Creek, Loyalsock Creek, and Muncy..., Pennsylvania (All Jurisdictions)'' addressed the flooding sources Big Run, Little Loyalsock Creek, Loyalsock... Sullivan County, Pennsylvania (All Jurisdictions) Big Run At the Muncy Creek +968 +965 Township of Davidson...

76 FR 12665 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-08

... Areas. Specifically, it addresses the following flooding sources: Hungry Hollow Gulch, Ice House Creek, Ice House Creek Tributary A, Riggs Gulch, Spearfish Creek, and Unnamed Tributary to Higgins Gulch... Incorporated Areas'' addressed the following flooding sources: Hungry Hollow Gulch, Ice House Creek, Ice House...

A simulation for the gated weir opening of Wonokromo River, Rungkut District, Surabaya

NASA Astrophysics Data System (ADS)

Handajani, N.; Wahjudijanto, I.; Mu'afi, M.

2018-01-01

The gated weir is a weir that the crest elevation could be operated based on the flow through the river. The upstream water level of the gated weir could be controlled with gate opening or closing. This study applied a simulation with HEC-RAS 4,0 program in order to know the river hydraulic condition after the gated weir has built. According to the rainfall intensity from each sub-watershed, Distribution Log Pearson III with return period 50 years (Q50) was determined to calculate the design flood discharge. By using Rational Method, the design flood discharge is 470 m3/s. The Results show that capacity of the river is able to accomodate Q50 with discharge 470 m3/s and the gate should be fully opened during flood. This condition could passed the normal discharge at + 5.00 m elevation.

Simulation of Flood Profiles for Fivemile Creek at Tarrant, Alabama, 2006

USGS Publications Warehouse

Lee, K.G.; Hedgecock, T.S.

2007-01-01

A one-dimensional step-backwater model was used to simulate flooding conditions for Fivemile Creek at Tarrant, Alabama. The 100-year flood stage published in the current flood insurance study for Tarrant by the Federal Emergency Management Agency was significantly exceeded by the March 2000 and May 2003 floods in this area. A peak flow of 14,100 cubic feet per second was computed by the U.S. Geological Survey for the May 2003 flood in the vicinity of Lawson Road. Using this estimated peak flow, flood-plain surveys with associated roughness coefficients, and the surveyed high-water profile for the May 2003 flood, a flow model was calibrated to closely match this known event. The calibrated model was then used to simulate flooding for the 10-, 50-, 100-, and 500-year recurrence interval floods. The results indicate that for the 100-year recurrence interval, the flood profile is about 2.5 feet higher, on average, than the profile published by the Federal Emergency Management Agency. The absolute maximum and minimum difference is 6.80 feet and 0.67 foot, respectively. All water-surface elevations computed for the 100-year flood are higher than those published by the Federal Emergency Management Agency, except for cross section H. The results of this study provide the community with flood-profile information that can be used for existing flood-plain mitigation, future development, and safety plans for the city.

Development of a smart flood warning system in urban areas: A case study of Huwei area in Taiwan

NASA Astrophysics Data System (ADS)

Yang, Sheng-Chi; Hsu, Hao-Ming; Kao, Hong-Ming

2016-04-01

In this study, we developed a smart flood warning system to clearly understand flood propagations in urban areas. The science and technology park of Huwei, located in the southwest of Taiwan, was selected as a study area. It was designated to be an important urban area of optoelectronics and biotechnology. The region has an area about 1 km2 with approximately 1 km in both length and width. The discrepancy between the highest and lowest elevations is 6.3 m and its elevation decreases along the northeast to the southwest. It is an isolated urban drainage area due to its urban construction plan. The storm sewer system in this region includes three major networks that collect the runoff and drain to the detention pond where is located in the southwest corner of the region. The proposed smart flood warning system combines three important parts, i.e. the physical world, the cyber-physical interface, and the cyber space, to identify how the flood affects urban areas from now until the next three hours. In the physical world, when a rainfall event occurs, monitoring sensors (e.g. rainfall gauges and water level gauges built in the sewer system and ground surface), which are established in several essential locations of the study area, collect in situ hydrological data and then these data being transported to the cyber-physical interface. The cyber-physical interface is a data preprocess space that includes data analysis, quality control and assurance, and data integration and standardization to produce the validated data. In the cyber space, it has missions to receive the validated data from the cyber-physical interface and to run the time machine that has flood analyses of data mining, inundation scenarios simulation, risk and economic assessments, and so on, based on the validated data. After running the time machine, it offers the analyzed results related to flooding planning, mitigation, response, and recovery. According to the analyzed results, the decision supporting system, therefore, can publish warning information in urban areas at the right time. Keywords: flood warning system, flood mitigation, inundation.

44 CFR 68.11 - Determination.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Administrator for review and approval. The Administrator shall make the final base flood elevation determination...

44 CFR 68.1 - Purpose of part.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Insurance Administrator's base flood elevation determinations, whether proposed pursuant to section 1363(e...

44 CFR 68.11 - Determination.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Administrator for review and approval. The Administrator shall make the final base flood elevation determination...

44 CFR 68.11 - Determination.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Administrator for review and approval. The Administrator shall make the final base flood elevation determination...

44 CFR 68.1 - Purpose of part.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Insurance Administrator's base flood elevation determinations, whether proposed pursuant to section 1363(e...

44 CFR 68.1 - Purpose of part.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Insurance Administrator's base flood elevation determinations, whether proposed pursuant to section 1363(e...

Using multiple bed load measurements: Toward the identification of bed dilation and contraction in gravel-bed rivers

NASA Astrophysics Data System (ADS)

Marquis, G. A.; Roy, A. G.

2012-02-01

This study examines bed load transport processes in a small gravel-bed river (Béard Creek, Québec) using three complementary methods: bed elevation changes between successive floods, bed activity surveys using tags inserted into the bed, and bed load transport rates from bed load traps. The analysis of 20 flood events capable of mobilizing bed material led to the identification of divergent results among the methods. In particular, bed elevation changes were not consistent with the bed activity surveys. In many cases, bed elevation changes were significant (1 to 2 times the D50) even if the bed surface had not been activated during the flood, leading to the identification of processes of bed dilation and contraction that occurred over 10% to 40% of the bed surface. These dynamics of the river bed prevent accurate derivation of bed load transport rates from topographic changes, especially for low magnitude floods. This paper discusses the mechanisms that could explain the dilation and contraction of particles within the bed and their implications in fluvial dynamics. Bed contraction seems to be the result of the winnowing of the fine sediments under very low gravel transport. Bed dilation seems to occur on patches of the bed at the threshold of motion where various processes such as fine sediment infiltration lead to the maintenance of a larger sediment framework volume. Both processes are also influenced by flood history and the initial local bed state and in turn may have a significant impact on sediment transport and morphological changes in gravel-bed rivers.

Analysis of the transport of sediment by the Suncook River in Epsom, Pembroke, and Allenstown, New Hampshire, after the May 2006 flood

USGS Publications Warehouse

Flynn, Robert H.

2011-01-01

During May 13-16, 2006, rainfall in excess of 8.8 inches flooded central and southern New Hampshire. On May 15, 2006, a breach in a bank of the Suncook River in Epsom, New Hampshire, caused the river to follow a new path. In order to assess and predict the effect of the sediment in, and the subsequent flooding on, the river and flood plain, a study by the U.S. Geological Survey (USGS) characterizing sediment transport in the Suncook River was undertaken in cooperation with the Federal Emergency Management Agency (FEMA) and the New Hampshire Department of Environmental Services (NHDES). The U.S. Army Corps of Engineers (USACE) Hydrologic Engineering Center-River Analysis System (HEC-RAS) model was used to simulate flow and the transport of noncohesive sediments in the Suncook River from the upstream corporate limit of Epsom to the river's confluence with the Merrimack River in the Village of Suncook (Allenstown and Pembroke, N.H.), a distance of approximately 16 miles. In addition to determining total sediment loads, analyses in this study reflect flooding potentials for selected recurrence intervals that are based on the Suncook River streamgage flow data (streamgage 01089500) and on streambed elevations predicted by HEC-RAS for the end of water year 2010 (September 30, 2010) in the communities of Epsom, Pembroke, and Allenstown. This report presents changes in streambed and water-surface elevations predicted by the HEC-RAS model using data through the end of water year 2010 for the 50-, 10-, 2-, 1-, 0.2-percent annual exceedence probabilities (2-, 10-, 50-, 100-, and 500-year recurrence-interval floods, respectively), calculated daily and annual total sediment loads, and a determination of aggrading and degrading stream reaches. The model was calibrated and evaluated for a 400-day span from May 8, 2008 through June 11, 2009; these two dates coincided with field collection of stream cross-sectional elevation data. Seven sediment-transport functions were evaluated in the model with the Laursen (Copeland) sediment-transport function best describing the sediment load, transport behavior, and changes in streambed elevation for the specified spatial and temporal conditions of the 400-day calibration period. Simulation results from the model and field-collected sediment data indicate that, downstream of the avulsion channel, for the average daily mean flow during the study period, approximately 100 to 400 tons per day of sediment (varying with daily mean flow) was moving past the Short Falls Road Bridge over the Suncook River in Epsom, while approximately 0.05 to 0.5 tons per day of sediment was moving past the Route 28 bridge in Pembroke and Allenstown, and approximately 1 to 10 tons per day was moving past the Route 3 bridge in Pembroke and Allenstown. Changes in water-surface elevation that the model predicted for the end of water year 2010 to be a result of changes in streambed elevation ranged from a mean increase of 0.20 feet (ft) for the 50-percent annual exceedence-probability flood (2-year recurrence-interval flood) due to an average thalweg increase of 0.88 ft between the Short Falls Road Bridge and the Buck Street Dams in Pembroke and Allenstown to a mean decrease of 0.41 ft for the 50-percent annual exceedence-probability flood due to an average thalweg decrease of 0.49 ft above the avulsion in Epsom. An analysis of shear stress (force created by a fluid acting on sediment particles) was undertaken to determine potential areas of erosion and deposition. Based on the median grain size (d50) and shear stress analysis, the study found that in general, for floods greater than the 50-percent annual exceedence probability flood, the shear stress in the streambed is greater than the critical shear stress in much of the river study reach. The result is an expectation of streambed-sediment movement and erosion even at high exceedence-probability events, pending although the stream ultimately attains equilibrium through stream-stabilization measures or the adjustment of the river over time. The potential for aggradation in the Suncook River is greatest in the reach downstream of the avulsion. Specifically, these reaches are (1) downstream of the former sand pit from adjacent to Round Pond to downstream of the flood chute at the large meander bends, and (2) downstream of the Short Falls Road Bridge to approximately 3,800 ft upstream of the Route 28 bridge. The potential for degradation-net lowering of the streambed-is greatest for the reach upstream of the avulsion to the Route 4 bridge.

The Upper Mississippi River System—Topobathy

USGS Publications Warehouse

Stone, Jayme M.; Hanson, Jenny L.; Sattler, Stephanie R.

2017-03-23

The Upper Mississippi River System (UMRS), the navigable part of the Upper Mississippi and Illinois Rivers, is a diverse ecosystem that contains river channels, tributaries, shallow-water wetlands, backwater lakes, and flood-plain forests. Approximately 10,000 years of geologic and hydrographic history exist within the UMRS. Because it maintains crucial wildlife and fish habitats, the dynamic ecosystems of the Upper Mississippi River Basin and its tributaries are contingent on the adjacent flood plains and water-level fluctuations of the Mississippi River. Separate data for flood-plain elevation (lidar) and riverbed elevation (bathymetry) were collected on the UMRS by the U.S. Army Corps of Engineers’ (USACE) Upper Mississippi River Restoration (UMRR) Program. Using the two elevation datasets, the U.S. Geological Survey (USGS) Upper Midwest Environmental Sciences Center (UMESC) developed a systemic topobathy dataset.

No phenotypic plasticity in nest-site selection in response to extreme flooding events.

PubMed

Bailey, Liam D; Ens, Bruno J; Both, Christiaan; Heg, Dik; Oosterbeek, Kees; van de Pol, Martijn

2017-06-19

Phenotypic plasticity is a crucial mechanism for responding to changes in climatic means, yet we know little about its role in responding to extreme climatic events (ECEs). ECEs may lack the reliable cues necessary for phenotypic plasticity to evolve; however, this has not been empirically tested. We investigated whether behavioural plasticity in nest-site selection allows a long-lived shorebird ( Haematopus ostralegus ) to respond to flooding. We collected longitudinal nest elevation data on individuals over two decades, during which time flooding events have become increasingly frequent. We found no evidence that individuals learn from flooding experiences, showing nest elevation change consistent with random nest-site selection. There was also no evidence of phenotypic plasticity in response to potential environmental cues (lunar nodal cycle and water height). A small number of individuals, those nesting near an artificial sea wall, did show an increase in nest elevation over time; however, there is no conclusive evidence this occurred in response to ECEs. Our study population showed no behavioural plasticity in response to changing ECE patterns. More research is needed to determine whether this pattern is consistent across species and types of ECEs. If so, ECEs may pose a major challenge to the resilience of wild populations.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

78 FR 8089 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-05

... flooding sources Big Run, Little Loyalsock Creek, Loyalsock Creek, and Muncy Creek. DATES: Comments are to..., Pennsylvania (All Jurisdictions)'' addressed the flooding sources Big Run, Little Loyalsock Creek, Loyalsock... Sullivan County, Pennsylvania (All Jurisdictions) Big Run At the Muncy Creek +968 +965 Township of Davidson...

76 FR 26982 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-10

.... Specifically, it addresses the flooding source Licking River (Cave Run Lake). DATES: Comments are to be... Incorporated Areas,'' addressed the flooding source Licking River (Cave Run Lake). That table contained... River (Cave Run Lake)....... At the Buck Creek None +765 City of Frenchburg, confluence. Unincorporated...

44 CFR 67.10 - Rates during pendency of final determination.

Code of Federal Regulations, 2014 CFR

2014-10-01

... MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.10 Rates during pendency of final... a participating community shall be denied the right to purchase flood insurance at the subsidized...

Delineation of flooding within the upper Mississippi River Basin, 1993-flood of June 29-September 18, 1993, in Iowa City and vicinity, Iowa

USGS Publications Warehouse

Schaap, Bryan D.; Harvey, Craig A.

1995-01-01

The hydrologic investigations atlas shows the areas in and around Iowa City, Iowa, that were flooded by the Iowa River in 1993. This map also depicts the Federal Emergency Management Agency (FEMA) 100-year flood boundaries. The drainage basin of the Iowa River at Iowa City received well over 100 percent of normal rainfall in June, July, and August, 1993. At the Cedar Rapids airport, located about 20 miles north-northwest of Iowa City, July rainfall was 414 percent of normal. The discharges at U.S. Geological Survey streamflow-gaging stations on the Iowa River upstream of Coralville Reservoir, just downstream from Coralville Reservoir, and at Iowa City are shown. A profile of the maximum water-surface elevations of the 1993 flood in Iowa City and vicinity is higher than the FEMA 100-year flood profile. The water-surface elevation of Coralville Reservoir is shown from June 29-September 18, 1993.

44 CFR 68.9 - Admissible evidence.

Code of Federal Regulations, 2013 CFR

2013-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING... base flood elevations of any other community, such determination, decision, or finding of fact shall...

44 CFR 68.4 - Hearing board.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Judge who are qualified in the technical field of flood elevation determinations. The Judge shall...

44 CFR 68.9 - Admissible evidence.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING... base flood elevations of any other community, such determination, decision, or finding of fact shall...

44 CFR 68.4 - Hearing board.

Code of Federal Regulations, 2010 CFR

2010-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Judge who are qualified in the technical field of flood elevation determinations. The Judge shall...

44 CFR 68.4 - Hearing board.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES... Judge who are qualified in the technical field of flood elevation determinations. The Judge shall...

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.

Magnitude and frequency of flooding on the Myakka River, Southwest Florida

USGS Publications Warehouse

Hammett, K.M.; Turner, J.F.; Murphy, W.R.

1978-01-01

Increasing numbers of urban and agricultural developments are being located on waterfront property in the Myakka River flood plain in southwest Florida. Under natural conditions, a large depression, Tatum Sawgrass, was available as a flood storage area in the upper Myakka River basin. Construction of dikes across the lower part of Tatum Sawgrass has restricted use of the depression for temporary storage of Myakka River flood water overflow, and has resulted in increased flood-peak discharges and flood heights in downstream reaches of the Myakka River. The difference between natural and diked condition flood-peak discharges and flood heights is presented to illustrate the effects of the dikes. Flood-peak discharges, water-surface elevations and flood profiles also are provided for diked conditions. Analytical procedures used to evaluate diking effects are described in detail. The study reach includes Myakka River main stem upstream from U.S. Highway 41, near Myakka Shores in Sarasota County, to State Road 70 near Myakka City in Manatee County (including Tatum Sawgrass and Clay Gully), and Blackburn Canal from Venice By-Way to Myakka River. (Woodard-USGS)

Nest-site selection and hatching success of waterbirds in coastal Virginia: some results of habitat manipulation

USGS Publications Warehouse

Rounds, R.A.; Erwin, R.M.; Portera, J.H.

2004-01-01

Rising sea levels in the mid-Atlantic region pose a long-term threat to marshes and their avian inhabitants. The Gull-billed Tern (Sterna nilotica), Common Tern (S. hirundo), Black Skimmer (Rynchops niger), and American Oystercatcher (Haematopus palliatus), species of concern in Virginia, nest on low shelly perimeters of salt marsh islands on the Eastern Shore of Virginia. Marsh shellpiles are free of mammalian predators, but subject to frequent floods that reduce reproductive success. In an attempt to examine nest-site selection, enhance habitat, and improve hatching success, small (2 ? 2 m) plots on five island shellpiles were experimentally elevated, and nest-site selection and hatching success were monitored from 1 May to 1 August, 2002. In addition, location, elevation, and nesting performance of all other nests in the colonies were also monitored. No species selected the elevated experimental plots preferentially over adjacent control plots at any of the sites. When all nests were considered, Common Tern nests were located significantly lower than were random point elevations at two sites, as they tended to concentrate on low-lying wrack. At two other sites, however, Common Tern nests were significantly higher than were random points. Gull-billed Terns and American Oystercatchers showed a weak preference for higher elevations on bare shell at most sites. Hatching success was not improved on elevated plots, despite the protection they provided from flooding. Because of a 7 June flood, when 47% of all nests flooded, hatching success for all species was low. Nest elevation had the strongest impact on a nest's probability of hatching, followed by nest-initiation date. Predation rates were high at small colonies, and Ruddy Turnstones (Arenaria interpres) depredated 90% of early Gull-billed Tern nests at one shellpile. The importance of nest elevation and flooding on hatching success demonstrates the potential for management of certain waterbird nesting sites. Facing threats from predators on barrier islands and rising sea levels especially in the mid-Atlantic region, several species of nesting waterbirds may benefit dramatically with modest manipulation of even small habitat patches on isolated marsh islands.

Arsenic contamination in New Orleans soil: temporal changes associated with flooding.

PubMed

Rotkin-Ellman, Miriam; Solomon, Gina; Gonzales, Christopher R; Agwaramgbo, Lovell; Mielke, Howard W

2010-01-01

The flooding of New Orleans in late August and September 2005 caused widespread sediment deposition in the flooded areas of the city. Post-flood sampling by US EPA revealed that 37% of sediment samples exceeded Louisiana corrective screening guidelines for arsenic of 12mg/kg, but there was debate over whether this contamination was pre-existing, as almost no pre-flood soil sampling for arsenic had been done in New Orleans. In this study, archived soil samples collected in 1998-1999 were location-matched with 70 residential sites in New Orleans where post-flood arsenic concentrations were elevated. Those same locations were sampled again during the recovery period 18 months later. During the recovery period, sampling for arsenic was also done for the first time at school sites and playgrounds within the flooded zone. Every sample of sediment taken 1-10 months after the flood exceeded the arsenic concentration found in the matched pre-flood soils. The average difference between the two sampling periods was 19.67mg/kg (95% CI 16.63-22.71) with a range of 3.60-74.61mg/kg. At virtually all of these sites (97%), arsenic concentrations decreased substantially by 18 months into the recovery period when the average concentration of matched samples was 3.26mg/kg (95% CI 1.86-4.66). However, 21 (30%) of the samples taken during the recovery period still had higher concentrations of arsenic than the matched sample taken prior to the flooding. In addition, 33% of samples from schoolyards and 13% of samples from playgrounds had elevated arsenic concentrations above the screening guidelines during the recovery period. These findings suggest that the flooding resulted in the deposition of arsenic-contaminated sediments. Diminution of the quantity of sediment at many locations has significantly reduced overall soil arsenic concentrations, but some locations remain of concern for potential long-term soil contamination.

Three Gorges Dam: Impact of Water Level Changes on the Density of Schistosome-Transmitting Snail Oncomelania hupensis in Dongting Lake Area, China

PubMed Central

Wu, Jin-Yi; Zhou, Yi-Biao; Chen, Yue; Liang, Song; Li, Lin-Han; Zheng, Sheng-Bang; Zhu, Shao-ping; Ren, Guang-Hui; Song, Xiu-Xia; Jiang, Qing-Wu

2015-01-01

Background Schistosomiasis remains an important public health issue in China and worldwide. Oncomelania hupensis is the unique intermediate host of schistosoma japonicum, and its change influences the distribution of S. japonica. The Three Gorges Dam (TGD) has substantially changed the ecology and environment in the Dongting Lake region. This study investigated the impact of water level and elevation on the survival and habitat of the snails. Methods Data were collected for 16 bottomlands around 4 hydrological stations, which included water, density of living snails (form the Anxiang Station for Schistosomiasis Control) and elevation (from Google Earth). Based on the elevation, sixteen bottomlands were divided into 3 groups. ARIMA models were built to predict the density of living snails in different elevation areas. Results Before closure of TGD, 7 out of 9 years had a water level beyond the warning level at least once at Anxiang hydrological station, compared with only 3 out of 10 years after closure of TGD. There were two severe droughts that happened in 2006 and 2011, with much fewer number of flooding per year compared with other study years. Overall, there was a correlation between water level changing and density of living snails variation in all the elevations areas. The density of living snails in all elevations areas was decreasing after the TGD was built. The relationship between number of flooding per year and the density of living snails was more pronounced in the medium and high elevation areas; the density of living snails kept decreasing from 2003 to 2014. In low elevation area however, the density of living snails decreased after 2003 first and turned to increase after 2011. Our ARIMA prediction models indicated that the snails would not disappear in the Dongting Lake region in the next 7 years. In the low elevation area, the density of living snails would increase slightly, and then stabilize after the year 2017. In the medium elevation region, the change of the density of living snails would be more obvious and would increase till the year 2020. In the high elevation area, the density of living snails would remain stable after the year 2015. Conclusion The TGD influenced water levels and reduced the risk of flooding and the density of living snails in the study region. Based on our prediction models, the density of living snails in all elevations tends to be stabilized. Control of S. japonica would continue to be an important task in the study area in the coming decade. PMID:26114956

24 CFR 55.2 - Terminology.

Code of Federal Regulations, 2014 CFR

2014-04-01

... or inoperative during flood and storm events (e.g., data storage centers, generating plants...” (§ 55.2(b)(5)). When FEMA provides interim flood hazard data, such as Advisory Base Flood Elevations... data may be used as “best available information” in accordance with Executive Order 11988. However, a...

44 CFR 65.6 - Revision of base flood elevation determinations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program... new discharge estimates. (6) Any computer program used to perform hydrologic or hydraulic analyses in... control and/or the regulation of flood plain lands. For computer programs adopted by non-Federal agencies...

44 CFR 65.6 - Revision of base flood elevation determinations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program... new discharge estimates. (6) Any computer program used to perform hydrologic or hydraulic analyses in... control and/or the regulation of flood plain lands. For computer programs adopted by non-Federal agencies...

44 CFR 65.6 - Revision of base flood elevation determinations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program... new discharge estimates. (6) Any computer program used to perform hydrologic or hydraulic analyses in... control and/or the regulation of flood plain lands. For computer programs adopted by non-Federal agencies...

44 CFR 65.6 - Revision of base flood elevation determinations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program... new discharge estimates. (6) Any computer program used to perform hydrologic or hydraulic analyses in... control and/or the regulation of flood plain lands. For computer programs adopted by non-Federal agencies...

44 CFR 68.3 - Right to administrative hearings.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program... Insurance Administrator's flood elevation determination established pursuant to § 67.8 of this subchapter...

Simulation of water-surface elevations for a hypothetical 100-year peak flow in Birch Creek at the Idaho National Engineering and Environmental Laboratory, Idaho

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

Berenbrock, C.; Kjelstrom, L.C.

1997-10-01

Delineation of areas at the Idaho National Engineering and Environmental Laboratory that would be inundated by a 100-year peak flow in Birch Creek is needed by the US Department of Energy to fulfill flood-plain regulatory requirements. Birch Creek flows southward about 40 miles through an alluvium-filled valley onto the northern part of the Idaho National Engineering and Environmental laboratory site on the eastern Snake River Plain. The lower 10-mile reach of Birch Creek that ends in Birch Creek Playa near several Idaho National Engineering and Environmental Laboratory facilities is of particular concern. Twenty-six channel cross sections were surveyed to developmore » and apply a hydraulic model to simulate water-surface elevations for a hypothetical 100-year peak flow in Birch Creek. Model simulation of the 100-year peak flow (700 cubic feet per second) in reaches upstream from State Highway 22 indicated that flow was confined within channels even when all flow was routed to one channel. Where the highway crosses Birch Creek, about 315 cubic feet per second of water was estimated to move downstream--115 cubic feet per second through a culvert and 200 cubic feet per second over the highway. Simulated water-surface elevation at this crossing was 0.8 foot higher than the elevation of the highway. The remaining 385 cubic feet per second flowed southwestward in a trench along the north side of the highway. Flow also was simulated with the culvert removed. The exact location of flood boundaries on Birch Creek could not be determined because of the highly braided channel and the many anthropogenic features (such as the trench, highway, and diversion channels) in the study area that affect flood hydraulics and flow. Because flood boundaries could not be located exactly, only a generalized flood-prone map was developed.« less

Scoping of Flood Hazard Mapping Needs for Coos County, New Hampshire

DTIC Science & Technology

2006-01-01

Technical Partner DEM Digital Elevation Model DFIRM Digital Flood Insurance Rate Map DOQ Digital Orthophoto Quadrangle DOQQ Digital Ortho Quarter Quadrangle...color Digital Orthophoto Quadrangles (DOQs)). Remote sensing, base map information, GIS data (for example, contour data, E911 data, Digital Elevation...the feature types found on USGS topographic maps. More recently developed data were derived from digital orthophotos providing improved base map

Development of flood-inundation maps for the Mississippi River in Saint Paul, Minnesota

USGS Publications Warehouse

Czuba, Christiana R.; Fallon, James D.; Lewis, Corby R.; Cooper, Diane F.

2014-01-01

Digital flood-inundation maps for a 6.3-mile reach of the Mississippi River in Saint Paul, Minnesota, were developed through a multi-agency effort by the U.S. Geological Survey in cooperation with the U.S. Army Corps of Engineers and in collaboration with the National Weather Service. The inundation maps, which can be accessed through the U.S. Geological Survey Flood Inundation Mapping Science Web site at http://water.usgs.gov/osw/flood_inundation/ and the National Weather Service Advanced Hydrologic Prediction Service site at http://water.weather.gov/ahps/inundation.php, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey streamgage at the Mississippi River at Saint Paul (05331000). The National Weather Service forecasted peak-stage information at the streamgage may be used in conjunction with the maps developed in this study to show predicted areas of flood inundation. In this study, flood profiles were computed for the Mississippi River by means of a one-dimensional step-backwater model. The hydraulic model was calibrated using the most recent stage-discharge relation at the Robert Street location (rating curve number 38.0) of the Mississippi River at Saint Paul (streamgage 05331000), as well as an approximate water-surface elevation-discharge relation at the Mississippi River at South Saint Paul (U.S. Army Corps of Engineers streamgage SSPM5). The model also was verified against observed high-water marks from the recent 2011 flood event and the water-surface profile from existing flood insurance studies. The hydraulic model was then used to determine 25 water-surface profiles for flood stages at 1-foot intervals ranging from approximately bankfull stage to greater than the highest recorded stage at streamgage 05331000. The simulated water-surface profiles were then combined with a geographic information system digital elevation model, derived from high-resolution topography data, to delineate potential areas flooded and to determine the water depths within the inundated areas for each stage at streamgage 05331000. The availability of these maps along with information regarding current stage at the U.S. Geological Survey streamgage and forecasted stages from the National Weather Service provides enhanced flood warning and visualization of the potential effects of a forecasted flood for the city of Saint Paul and its residents. The maps also can aid in emergency management planning and response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.

Large projected increases in rain-on-snow flood potential over western North America

NASA Astrophysics Data System (ADS)

Musselman, K. N.; Ikeda, K.; Barlage, M. J.; Lehner, F.; Liu, C.; Newman, A. J.; Prein, A. F.; Mizukami, N.; Gutmann, E. D.; Clark, M. P.; Rasmussen, R.

2017-12-01

In the western US and Canada, some of the largest annual flood events occur when warm storm systems drop substantial rainfall on extensive snow-cover. For example, last winter's Oroville dam crisis in California was exacerbated by rapid snowmelt during a rain-on-snow (ROS) event. We present an analysis of ROS events with flood-generating potential over western North America simulated at high-resolution by the Weather Research and Forecasting (WRF) model run for both a 13-year control time period and re-run with a `business-as-usual' future (2071-2100) climate scenario. Daily ROS with flood-generating potential is defined as rainfall of at least 10 mm per day falling on snowpack of at least 10 mm water equivalent, where the sum of rainfall and snowmelt contains at least 20% snowmelt. In a warmer climate, ROS is less frequent in regions where it is historically common, and more frequent elsewhere. This is evidenced by large simulated reductions in snow-cover and ROS frequency at lower elevations, particularly in warmer, coastal regions, and greater ROS frequency at middle elevations and in inland regions. The same trend is reflected in the annual-average ROS runoff volume (rainfall + snowmelt) aggregated to major watersheds; large reductions of 25-75% are projected for much of the U.S. Pacific Northwest, while large increases are simulated for the Colorado River basin, western Canada, and the higher elevations of the Sierra Nevada. In the warmer climate, snowmelt contributes substantially less to ROS runoff per unit rainfall, particularly in inland regions. The reduction in snowmelt contribution is due to a shift in ROS timing from warm spring events to cooler winter conditions and/or from warm, lower elevations to cool, higher elevations. However, the slower snowmelt is offset by an increase in rainfall intensity, maintaining the flood potential of ROS at or above historical levels. In fact, we report large projected increases in the intensity of extreme ROS events. The projected increases in ROS flood potential are highest in historically flood-prone mountain basins and the Canadian Prairies. Increases in extreme ROS event intensity, together with a greater proportion of precipitation falling as rain, have critical implications on the climate resilience of regional flood control systems.

DEM-based Approaches for the Identification of Flood Prone Areas

NASA Astrophysics Data System (ADS)

Samela, Caterina; Manfreda, Salvatore; Nardi, Fernando; Grimaldi, Salvatore; Roth, Giorgio; Sole, Aurelia

2013-04-01

The remarkable number of inundations that caused, in the last decades, thousands of deaths and huge economic losses, testifies the extreme vulnerability of many Countries to the flood hazard. As a matter of fact, human activities are often developed in the floodplains, creating conditions of extremely high risk. Terrain morphology plays an important role in understanding, modelling and analyzing the hydraulic behaviour of flood waves. Research during the last 10 years has shown that the delineation of flood prone areas can be carried out using fast methods that relay on basin geomorphologic features. In fact, the availability of new technologies to measure surface elevation (e.g., GPS, SAR, SAR interferometry, RADAR and LASER altimetry) has given a strong impulse to the development of Digital Elevation Models (DEMs) based approaches. The identification of the dominant topographic controls on the flood inundation process is a critical research question that we try to tackle with a comparative analysis of several techniques. We reviewed four different approaches for the morphological characterization of a river basin with the aim to provide a description of their performances and to identify their range of applicability. In particular, we explored the potential of the following tools. 1) The hydrogeomorphic method proposed by Nardi et al. (2006) which defines the flood prone areas according to the water level in the river network through the hydrogeomorphic theory. 2) The linear binary classifier proposed by Degiorgis et al. (2012) which allows distinguishing flood-prone areas using two features related to the location of the site under exam with respect to the nearest hazard source. The two features, proposed in the study, are the length of the path that hydrologically connects the location under exam to the nearest element of the drainage network and the difference in elevation between the cell under exam and the final point of the same path. 3) The method by Manfreda et al. (2011) that suggested a modified Topographic Index (TIm) for the identification of flood prone area. 4) The downslope index proposed by Hjerdt et al. (2004) that quantifies the topographic controls on hydrology by evaluating head differences following the (surface) flow path in the steepest direction. The method does not use the exit point at the stream as reference; instead, the algorithm looks at how far a parcel of water has to travel along its flow path to lose a given head potential, d [m]. This last index was not defined with the aim to describe flood prone areas; in fact it represents an interesting alternative descriptor of morphological features that deserve to be tested. Analyses have been carried out for some Italian catchments. The outcomes of the four methods are presented using, for calibration and validation purposes, flood inundation maps made available by River Basin Authorities. The aim is, therefore, to evaluate the reliability and the relative errors in the detection of the areas subject to the flooding hazard. These techniques should not be considered as an alternative of traditional procedures, but additional tool for the identification of flood-prone areas and hazard graduation over large regions or when a preliminary identification is needed. Reference Degiorgis M., G. Gnecco, S. Gorni, G. Roth, M. Sanguineti, A. C. Taramasso, Classifiers for the detection of flood-prone areas using remote sensed elevation data, J. Hydrol., 470-471, 302-315, 2012. Hjerdt, K. N., J. J. McDonnell, J. Seibert, A. Rodhe, A new topographic index to quantify downslope controls on local drainage, Water Resour. Res., 40, W05602, 2004. Manfreda, S., M. Di Leo, A. Sole, Detection of Flood Prone Areas using Digital Elevation Models, Journal of Hydrologic Engineering, Vol. 16, No. 10, 781-790, 2011. Nardi, F., E. R. Vivoni, S. Grimaldi, Investigating a floodplain scaling relation using a hydrogeomorphic delineation method, Water Resour. Res., 42, W09409, 2006.

Floods of July 12, 1972, March 19, 1979, and June 15, 1991, in the Turkey River Basin, northeast Iowa

USGS Publications Warehouse

Eash, D.A.; Koppensteiner, B.A.

1996-01-01

Water-surface-elevation profiles and peak discharges for the floods of July 12, 1972, March 19, 1979, and June 15, 1991, in the Turkey River Basin, northeast Iowa, are presented in this report. The profiles illustrate the 1979 and 1991 floods along the Turkey River in Fayette and Clayton Counties and along the Volga River in Clayton County; the 1991 flood along Roberts Creek in Clayton County and along Otter Creek in Fayette County; and the 1972 flood along the Turkey River in Winneshiek and Fayette Counties. Watersurface elevations for the flood of March 19,1979, were collected by the Iowa Natural Resources Council. The June 15, 1991, flood on the Turkey River at Garber (station number 05412500) is the largest known flood-peak discharge at the streamflow-gaging station for the period 1902-95. The peak discharge for June 15, 1991, of 49,900 cubic feet per second was 1.4 times larger than the 100-year recurrence-interval discharge. The report provides information on flood stages and discharges and floodflow frequencies for streamflow-gaging stations in the Turkey River Basin using flood information collected during 1902-95. Information on temporary bench marks and reference points established in the Turkey River Basin during 1981, 1992, and 1996 also is included in the report. A flood history describes rainfall conditions for floods that occurred during 1922, 1947, 1972, 1979, and 1991.

An Approach to Flooding Inundation Combining the Streamflow Prediction Tool (SPT) and Downscaled Soil Moisture

NASA Astrophysics Data System (ADS)

Cotterman, K. A.; Follum, M. L.; Pradhan, N. R.; Niemann, J. D.

2017-12-01

Flooding impacts numerous aspects of society, from localized flash floods to continental-scale flood events. Many numerical flood models focus solely on riverine flooding, with some capable of capturing both localized and continental-scale flood events. However, these models neglect flooding away from channels that are related to excessive ponding, typically found in areas with flat terrain and poorly draining soils. In order to obtain a holistic view of flooding, we combine flood results from the Streamflow Prediction Tool (SPT), a riverine flood model, with soil moisture downscaling techniques to determine if a better representation of flooding is obtained. This allows for a more holistic understanding of potential flood prone areas, increasing the opportunity for more accurate warnings and evacuations during flooding conditions. Thirty-five years of near-global historical streamflow is reconstructed with continental-scale flow routing of runoff from global land surface models. Elevation data was also obtained worldwide, to establish a relationship between topographic attributes and soil moisture patterns. Derived soil moisture data is validated against observed soil moisture, increasing confidence in the ability to accurately capture soil moisture patterns. Potential flooding situations can be examined worldwide, with this study focusing on the United States, Central America, and the Philippines.

44 CFR 68.5 - Establishment of a docket.

Code of Federal Regulations, 2011 CFR

2011-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE... docket shall include, for each appeal, copies of all materials contained in the flood elevation...

44 CFR 68.5 - Establishment of a docket.

Code of Federal Regulations, 2013 CFR

2013-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE... docket shall include, for each appeal, copies of all materials contained in the flood elevation...

44 CFR 68.5 - Establishment of a docket.

Code of Federal Regulations, 2010 CFR

2010-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE... docket shall include, for each appeal, copies of all materials contained in the flood elevation...

76 FR 72961 - Flood Hazard Determinations (Including Flood Elevation Determinations)-Change in Notification and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

... opportunity for comment and appeal. These other types of flood hazard determinations include new and modified... Appeal Procedures AGENCY: Federal Emergency Management Agency, DHS. ACTION: Notice. SUMMARY: Pursuant to... rules. This new procedure will not affect the notice or appeals process for these determinations. FEMA...

77 FR 50665 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-22

... addresses the flooding sources Allegheny River, East Sandy Creek, and Sugar Creek. DATES: Comments are to be... Jurisdictions)'' addressed the flooding sources Allegheny River, East Sandy Creek, and Sugar Creek. That table...,000 None +961 feet upstream of the confluence with the Allegheny River. Sugar Creek Approximately 0.79...

76 FR 16722 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-25

..., Overflow Creek Tributary, Red Cut Slough, Red Cut Slough Tributary, Red Cut Slough Tributary 2, and Red Cut... flooding sources: Gum Creek Flooding Effects, Little Red River, Overflow Creek Tributary, Red Cut Slough, Red Cut Slough Tributary, Red Cut Slough Tributary 2, and Red Cut Slough Tributary A. In this notice...

44 CFR 66.1 - Purpose of part.

Code of Federal Regulations, 2013 CFR

2013-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION WITH LOCAL OFFICIALS § 66.1 Purpose of part. (a) The purpose of this part is to comply with section 206 of the Flood Disaster Protection Act of 1973 (42 U.S.C. 4107) by establishing procedures for flood elevation...

44 CFR 66.1 - Purpose of part.

Code of Federal Regulations, 2012 CFR

2012-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION WITH LOCAL OFFICIALS § 66.1 Purpose of part. (a) The purpose of this part is to comply with section 206 of the Flood Disaster Protection Act of 1973 (42 U.S.C. 4107) by establishing procedures for flood elevation...

44 CFR 67.10 - Rates during pendency of final determination.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.10 Rates during pendency of final determination. (a) Until... community shall be denied the right to purchase flood insurance at the subsidized rate. (b) After the final...

44 CFR 66.1 - Purpose of part.

Code of Federal Regulations, 2014 CFR

2014-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION WITH LOCAL OFFICIALS § 66.1 Purpose of part. (a) The purpose of this part is to comply with section 206 of the Flood Disaster Protection Act of 1973 (42 U.S.C. 4107) by establishing procedures for flood elevation...

44 CFR 66.1 - Purpose of part.

Code of Federal Regulations, 2011 CFR

2011-10-01

... SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program CONSULTATION WITH LOCAL OFFICIALS § 66.1 Purpose of part. (a) The purpose of this part is to comply with section 206 of the Flood Disaster Protection Act of 1973 (42 U.S.C. 4107) by establishing procedures for flood elevation...

Impact on the Columbia River of an outburst of Spirit Lake

USGS Publications Warehouse

Sikonia, W.G.

1985-01-01

A one-dimensional sediment-transport computer model was used to study the effects of an outburst of Spirit Lake on the Columbia River. According to the model, flood sediment discharge to the Columbia from the Cowlitz would form a blockage to a height of 44 feet above the current streambed of the Columbia River, corresponding to a new streambed elevation of -3 feet, that would impound the waters of the Columbia River. For an average flow of 233,000 cubic feet in that river, water surface elevations would continue to increase for 16 days after the blockage had been formed. The river elevation at the Trojan nuclear power plant, 5 miles upstream of the Cowlitz River, would rise to 32 feet, compared to a critical elevation of 45 feet, above which the plant would be flooded. For comparison, the Columbia River at average flow without the blockage has an elevation at this location of 6 feet. Correspondingly high water surface elevations would occur along the river to Bonneville Dam , with that at Portland, Oregon, for example, rising also to 32 feet, compared to 10 feet without the blockage. (USGS)

The effect of floods on anemia among reproductive age women in Afghanistan.

PubMed

Oskorouchi, Hamid Reza; Nie, Peng; Sousa-Poza, Alfonso

2018-01-01

This study uses biomarker information from the 2013 National Nutrition Survey Afghanistan and satellite precipitation driven modeling results from the Global Flood Monitoring System to analyze how floods affect the probability of anemia in Afghan women of reproductive age (15-49). In addition to establishing a causal relation between the two by exploiting the quasi-random variation of floods in different districts and periods, the analysis demonstrates that floods have a significant positive effect on the probability of anemia through two possible transmission mechanisms. The first is a significant effect on inflammation, probably related to water borne diseases carried by unsafe drinking water, and the second is a significant negative effect on retinol concentrations. Because the effect of floods on anemia remains significant even after we control for anemia's most common causes, we argue that the condition may also be affected by elevated levels of psychological stress.

The effect of floods on anemia among reproductive age women in Afghanistan

PubMed Central

2018-01-01

This study uses biomarker information from the 2013 National Nutrition Survey Afghanistan and satellite precipitation driven modeling results from the Global Flood Monitoring System to analyze how floods affect the probability of anemia in Afghan women of reproductive age (15–49). In addition to establishing a causal relation between the two by exploiting the quasi-random variation of floods in different districts and periods, the analysis demonstrates that floods have a significant positive effect on the probability of anemia through two possible transmission mechanisms. The first is a significant effect on inflammation, probably related to water borne diseases carried by unsafe drinking water, and the second is a significant negative effect on retinol concentrations. Because the effect of floods on anemia remains significant even after we control for anemia’s most common causes, we argue that the condition may also be affected by elevated levels of psychological stress. PMID:29425219

Flood Inundation Modelling in the Kuantan River Basin using 1D-2D Flood Modeller coupled with ASTER-GDEM

NASA Astrophysics Data System (ADS)

Ng, Z. F.; Gisen, J. I.; Akbari, A.

2018-03-01

Topography dataset is an important input in performing flood inundation modelling. However, it is always difficult to obtain high resolution topography that provide accurate elevation information. Fortunately, there are some open source topography datasets available with reasonable resolution such as SRTM and ASTER-GDEM. In Malaysia particularly in Kuantan, the modelling research on the floodplain area is still lacking. This research aims to: a) to investigate the suitability of ASTER-GDEM to be applied in the 1D-2D flood inundation modelling for the Kuantan River Basin; b) to generate flood inundation map for Kuantan river basin. The topography dataset used in this study is ASTER-GDEM to generate physical characteristics of watershed in the basin. It is used to perform rainfall runoff modelling for hydrological studies and to delineate flood inundation area in the Flood Modeller. The results obtained have shown that a 30m resolution ASTER-GDEM is applicable as an input for the 1D-2D flood modelling. The simulated water level in 2013 has NSE of 0.644 and RSME of 1.259. As a conclusion, ASTER-GDEM can be used as one alternative topography datasets for flood inundation modelling. However, the flood level obtained from the hydraulic modelling shows low accuracy at flat urban areas.

Responses of black willow ( Salix nigra) cuttings to simulated herbivory and flooding

NASA Astrophysics Data System (ADS)

Li, Shuwen; Martin, Lili T.; Pezeshki, S. Reza; Shields, F. Douglas

2005-09-01

Herbivory and flooding influence plant species composition and diversity in many wetland ecosystems. Black willow ( Salix nigra) naturally occurs in floodplains and riparian zones of the southeastern United States. Cuttings from this species are used as a bioengineering tool for streambank stabilization and habitat rehabilitation. The present study was conducted to evaluate the photosynthetic and growth responses of black willow to simulated herbivory and flooding. Potted cuttings were subjected to three levels of single-event herbivory: no herbivory (control), light herbivory, and heavy herbivory; and three levels of flooding conditions: no flooding (control), continuous flooding, and periodic flooding. Results indicated that elevated stomatal conductance partially contributed to the increased net photosynthesis noted under both levels of herbivory on day 30. However, chlorophyll content was not responsible for the observed compensatory photosynthesis. Cuttings subjected to heavy herbivory accumulated the lowest biomass even though they had the highest height growth by the conclusion of the experiment. In addition, a reduction in root/shoot ratio was noted for plants subjected to continuous flooding with no herbivory. However, continuously flooded, lightly clipped plants allocated more resources to roots than shoots. This study provides evidence that it is feasible to use black willow for habitat rehabilitation along highly eroded streambanks where both flooding and herbivory are present.

The use of cartographic modeling to assess the impacts of coastal flooding: a case study of Port Said Governorate, Egypt.

PubMed

Abou Samra, Rasha M

2017-09-01

Low-set coastal areas are expected to aggravate inundation on account of sea level rise (SLR). The present study is planned to appraise the impacts of coastal flooding in Port Said city, Egypt by using remote sensing, GIS, and cartographic modeling techniques. To accomplish this scope, Landsat 8-OLI image dated 2016 and SRTM 1Arc-Second Digital Elevation Model (DEM) data were used. Landsat image was classified into seven land use and land cover (LULC) classes by using remote sensing and GIS's software. Different inundation scenarios 1.0, 2.0, and 3.0-m coastal elevation were used to figure the influence of SLR on the study area. Estimation of potential losses under SLR was made by overlaying the expected scenarios on land use. The inundation areas under the expected SLR scenarios of 1.0, 2.0, and 3.0 m were estimated at 827.49, 1072.67, and 1179.41 km 2 , respectively. In conclusion, this study demonstrated that expected coastal flooding scenarios will lead up to serious impacts on LULC classes and coastal features in the study area.

Fifty-Year Flood-Inundation Maps for Santa Rosa de Aguan, Honduras

USGS Publications Warehouse

Mastin, Mark C.; Olsen, T.D.

2002-01-01

After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the coastal municipality of Santa Rosa de Aguan that are prone to oceanic storm-surge flooding and wave action. The 50-year flood on the Rio Aguan (4,270 cubic meters per second), would inundate most of the area surveyed for this municipality and beyond. Therefore a detailed numerical hydraulic model was not developed for this municipality as it was for the others. The 50-year storm surge would likely produce higher water levels than the 50-year flood on the river during normal astronomical tides. The elevation of the 50-year storm surge was estimated to be 4.35 meters above normal sea level, based on hurricane probabilities and published storm-surge elevations associated with various hurricane categories. Flood-inundation maps, including areas of wave-action hazard and a color-shaded elevation map, were created from the available data and the estimated 50-year storm tide. Geographic Information System (GIS) coverages of the hazard areas are available on a computer in the municipality of Santa Rosa de Aguan as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Data Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the maps in much more detail than is possible using the maps in this report.

Flood of July 12-13, 2004, Burlington and Camden Counties, South-Central New Jersey

USGS Publications Warehouse

Protz, Amy R.; Reed, Timothy J.

2006-01-01

Intense rainfall inundated south-central New Jersey on July 12-13, 2004, causing major flooding with heavy property, road, and bridge damage in Burlington and Camden Counties. Forty-five dams were topped or damaged, or failed completely. The affected areas were in the Rancocas Creek, Cooper River, and Pennsauken Creek Basins. The U.S. Geological Survey (USGS) documented peak stream elevations and flows at 56 selected sites within the affected area. With rainfall totals averaging more than 6 inches throughout the three basins, peak-of-record flood elevations and streamflows occurred at all but one USGS stream gage, where the previous record was tied. Flood-frequency recurrence-intervals ranged from 30 to greater than 100 years and maximum streamflow per square mile ranged from 13.9 to 263 cubic feet per second per square mile (ft3/s/mi2). Peak streamflow at USGS stream gages surrounding the affected basins are associated with considerably lower recurrence intervals and demonstrate the limited extent of the flood. A high tide of about 1 foot above monthly mean high tide did not contribute to high-water conditions. Low ground-water levels prior to the rainfall helped to mitigate flooding in the affected basins. Compared with historical floods in the Rancocas Creek Basin during 1938-40, the July 2004 flood had greater streamflow, but lower stream elevations. Property damage from the event was estimated at $50 million. Governor James E. McGreevy declared a State of Emergency in Burlington and Camden Counties on July 13, 2004. After assessment of the damage by the Federal Emergency Management Agency (FEMA), President George W. Bush declared Burlington and Camden Counties disaster areas on July 16, 2004.

Conditions and processes affecting sand resources at archeological sites in the Colorado River corridor below Glen Canyon Dam, Arizona

USGS Publications Warehouse

East, Amy E.; Collins, Brian D.; Sankey, Joel B.; Corbett, Skye C.; Fairley, Helen C.; Caster, Joshua J.

2016-05-17

We conclude that most of the river-corridor archeological sites are at elevated risk of net erosion under present dam operations. In the present flow regime, controlled floods do not simulate the magnitude or frequency of natural floods, and are not large enough to deposit sand at elevations that were flooded at annual to decadal intervals in predam time. For archeological sites that depend upon river-derived sand, we infer elevated erosion risk owing to a combination of reduced sand supply (both fluvial and aeolian) through (1) the lower-than-natural flood magnitude, frequency, and sediment supply of the controlled-flooding protocol; (2) reduction of open, dry sand area available for wind redistribution under current normal (nonflood) dam operations, which do not include flows as low as natural seasonal low flows and do include substantial daily flow fluctuations; and (3) impeded aeolian sand entrainment and transport owing to increased riparian vegetation growth in the absence of larger, more-frequent floods. If dam operations were to increase the supply of sand available for windblown transport—for example, through larger floods, sediment augmentation, or increased fluvial sandbar exposure by low flows—and also decrease riparian vegetation, the prevalence of active aeolian sand could increase over time, and the propensity for unmitigated gully erosion could decrease. Although the evolution of river-corridor landscapes and archeological sites has been altered fundamentally by the lack of large, sediment-rich floods (flows on the order of 5,000 m3/s), some combination of sediment-rich flows above 1,270 m3/s, seasonal flows below 226 m3/s, and riparian-vegetation removal might increase the preservation potential for sand-dependent archeological resources in the Colorado River corridor.

Development of Flood Inundation Libraries using Historical Satellite Data and DEM for Part of Godavari Basin: An Approach Towards Better Flood Management

NASA Astrophysics Data System (ADS)

Bhatt, C. M.; Rao, G. S.; Patro, B.

2014-12-01

Conventional method of identifying areas to be inundated for issuing flood alert require inputs like discharge data, fine resolution digital elevation model (DEM), software for modelling and technically trained manpower to interpret the results meaningfully. Due to poor availability of these inputs, including good network of historical hydrological observations and limitation of time, quick flood early warning becomes a difficult task. Presently, based on the daily river water level and forecasted water level for major river systems in India, flood alerts are provided which are non-spatial in nature and does not help in understanding the inundation (spatial dimension) which may be caused at various water levels. In the present paper a concept for developing a series of flood-inundation map libraries two approaches are adopted one by correlating inundation extent derived from historical satellite data analysis with the corresponding water level recorded by the gauge station and the other simulation of inundation using digital elevation model (DEM's) is demonstrated for a part of Godavari Basin. The approach explained can be one of quick and cost-effective method for building a library of flood inundation extents, which can be utilized during flood disaster for alerting population and taking the relief and rescue operations. This layer can be visualized from a spatial dimension together with other spatial information like administrative boundaries, transport network, land use and land cover, digital elevation data and satellite images for better understanding and visualization of areas to be inundated spatially on free web based earth visualization portals like ISRO's Bhuvan portal (http://bhuvan.nrsc.gov.in). This can help decision makers in taking quick appropriate measures for warning, planning relief and rescue operations for the population to get affected under that river stage.

Floods of 2011 in New York

USGS Publications Warehouse

Lumia, Richard; Firda, Gary D.; Smith, Travis L.

2014-01-01

Record rainfall combined with above-average temperatures and substantial spring snowmelt resulted in record flooding throughout New York during 2011. Rainfall totals in eastern New York were the greatest since 1895 and as much as 60 percent above the long-term average within the Catskill Mountains area and the Susquehanna River Basin. This report documents the three largest storms and resultant flooding during the year: (1) spring storm during April and May, (2) Tropical Storm Irene during August, and (3) remnants of Tropical Storm Lee during September. According to the Federal Emergency Management Agency (FEMA), the cost of these three storms exceeded $1 billion in Federal disaster assistance. A warm and wet spring in northern New York resulted in record flooding at 21 U.S. Geological Survey (USGS) active streamgages during late April to early May with the annual exceedance probabilities (AEPs) of 11 peak discharges equaling or exceeding 1 percent. Nearly 5 inches of rain during late April combined with a rapidly melting snowpack caused widespread flooding throughout northern New York, resulting in many road closures, millions of dollars in damages, and 23 counties declared disaster areas and eligible for public assistance. On May 6, Lake Champlain recorded its highest lake level in over 140 years. Hurricane Irene entered New York State on August 28 as a tropical storm and traveled up the eastern corridor of the State, leaving a path of destruction and damage never seen in many parts of New York. Thirty-one counties in New York were declared disaster areas with damages of over $1.3 billion dollars and 10 reported deaths. Storm rainfall exceeded 18 inches in the Catskill Mountains area of southeastern New York with many other areas of eastern New York receiving over 7 inches. Catastrophic flooding resulted from the extreme rainfall in many locations, including Schoharie Creek and its tributaries, the eastern Delaware River Basin, the Ausable and Bouquet River Basins in northeastern New York, and several other stream basins throughout southeastern New York. Downstream reaches of the Mohawk River also had substantial flooding. Sixty-two USGS streamgages throughout eastern New York documented record high stream flows and elevations with AEPs of 25 peak discharges equaling or exceeding 1 percent. The USGS streamgage for the Schoharie Creek at Prattsville recorded its greatest peak discharge in 109 years of record at 120,000 cubic feet per second (greater than the 0.2-percent AEP discharge) on August 28. The peak water-surface elevation at the streamgage in Prattsville was 5 feet higher than its previous record in 1996. USGS personnel surveyed 184 high-water marks (HWMs) at 30 locations along an 84-mile reach of Schoharie Creek and compared the elevations to those published by FEMA for the 10-, 2-, 1-, and 0.2-percent AEP floods. Elevations in the lower reaches of the basin exceeded published elevations for the 0.2-percent AEP flood. Remnants of Tropical Storm Lee brought a third major storm to New York in September 2011. Moisture from Lee began moving into New York on September 7 and intensified over the already saturated Susquehanna River Basin. Most of the rain fell on September 8 with storm totals nearing 13 inches in some areas (12.73 inches at Apalachin in Tioga County). Major disaster declarations were issued for 15 counties in and around central New York, making them eligible for individual or public assistance. Ten USGS streamgages within the Susquehanna River Basin documented record-high stream discharges and elevations on September 8, and all were greater than the 1-percent AEP discharge. USGS personnel surveyed 20 HWMs at 18 locations along a 114- mile reach of the Susquehanna River and compared the elevations to those published by FEMA for the 10-, 2-, 1-, and 0.2-percent AEP floods. Several of the surveyed HWMs exceeded published elevations for the 0.2-percent AEP flood.

Comparing the Performance of Commonly Available Digital Elevation Models in GIS-based Flood Simulation

NASA Astrophysics Data System (ADS)

Ybanez, R. L.; Lagmay, A. M. A.; David, C. P.

2016-12-01

With climatological hazards increasing globally, the Philippines is listed as one of the most vulnerable countries in the world due to its location in the Western Pacific. Flood hazards mapping and modelling is one of the responses by local government and research institutions to help prepare for and mitigate the effects of flood hazards that constantly threaten towns and cities in floodplains during the 6-month rainy season. Available digital elevation maps, which serve as the most important dataset used in 2D flood modelling, are limited in the Philippines and testing is needed to determine which of the few would work best for flood hazards mapping and modelling. Two-dimensional GIS-based flood modelling with the flood-routing software FLO-2D was conducted using three different available DEMs from the ASTER GDEM, the SRTM GDEM, and the locally available IfSAR DTM. All other parameters kept uniform, such as resolution, soil parameters, rainfall amount, and surface roughness, the three models were run over a 129-sq. kilometer watershed with only the basemap varying. The output flood hazard maps were compared on the basis of their flood distribution, extent, and depth. The ASTER and SRTM GDEMs contained too much error and noise which manifested as dissipated and dissolved hazard areas in the lower watershed where clearly delineated flood hazards should be present. Noise on the two datasets are clearly visible as erratic mounds in the floodplain. The dataset which produced the only feasible flood hazard map is the IfSAR DTM which delineates flood hazard areas clearly and properly. Despite the use of ASTER and SRTM with their published resolution and accuracy, their use in GIS-based flood modelling would be unreliable. Although not as accessible, only IfSAR or better datasets should be used for creating secondary products from these base DEM datasets. For developing countries which are most prone to hazards, but with limited choices for basemaps used in hazards studies, the caution must be taken in the use of globally available GDEMs and higher-resolution DEMs must always be sought.

Feasibility Report and Final Environmental Impact Statement, Wisconsin River at Portage, Wisconsin, Feasibility Study for Flood Control. Appendixes.

DTIC Science & Technology

1983-12-01

therefore, any possible changes in floodplain regulation would be independent of project implementation. The existing regulation affects properties...to 0.4. Based on engineering experience there is a tendency toward independence as tributary drainage area size decreases. Frequency-discharge...stages on the Wisconsin River. Similarly the storage areas are analyzed as independent syste,, o thereby, reduction in flood elevations (routing) and

75 FR 59192 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-27

... of Perry, downstream of the Township of Toby. confluence with Black Fox Run. Approximately 480 feet... No. 97.022, ``Flood Insurance.'') Dated: September 13, 2010. Sandra K. Knight, Deputy Federal...

Analysis the Accuracy of Digital Elevation Model (DEM) for Flood Modelling on Lowland Area

NASA Astrophysics Data System (ADS)

Zainol Abidin, Ku Hasna Zainurin Ku; Razi, Mohd Adib Mohammad; Bukari, Saifullizan Mohd

2018-04-01

Flood is one type of natural disaster that occurs almost every year in Malaysia. Commonly the lowland areas are the worst affected areas. This kind of disaster is controllable by using an accurate data for proposing any kinds of solutions. Elevation data is one of the data used to produce solutions for flooding. Currently, the research about the application of Digital Elevation Model (DEM) in hydrology was increased where this kind of model will identify the elevation for required areas. University of Tun Hussein Onn Malaysia is one of the lowland areas which facing flood problems on 2006. Therefore, this area was chosen in order to produce DEM which focussed on University Health Centre (PKU) and drainage area around Civil and Environment Faculty (FKAAS). Unmanned Aerial Vehicle used to collect aerial photos data then undergoes a process of generating DEM according to three types of accuracy and quality from Agisoft PhotoScan software. The higher the level of accuracy and quality of DEM produced, the longer time taken to generate a DEM. The reading of the errors created while producing the DEM shows almost 0.01 different. Therefore, it has been identified there are some important parameters which influenced the accuracy of DEM.

Developing flood-inundation maps for Johnson Creek, Portland, Oregon

USGS Publications Warehouse

Stonewall, Adam J.; Beal, Benjamin A.

2017-04-14

Digital flood-inundation maps were created for a 12.9‑mile reach of Johnson Creek by the U.S. Geological Survey (USGS). The flood-inundation maps depict estimates of water depth and areal extent of flooding from the mouth of Johnson Creek to just upstream of Southeast 174th Avenue in Portland, Oregon. Each flood-inundation map is based on a specific water level and associated streamflow at the USGS streamgage, Johnson Creek at Sycamore, Oregon (14211500), which is located near the upstream boundary of the maps. The maps produced by the USGS, and the forecasted flood hydrographs produced by National Weather Service River Forecast Center can be accessed through the USGS Flood Inundation Mapper Web site (http://wimcloud.usgs.gov/apps/FIM/FloodInundationMapper.html).Water-surface elevations were computed for Johnson Creek using a combined one-dimensional and two‑dimensional unsteady hydraulic flow model. The model was calibrated using data collected from the flood of December 2015 (including the calculated streamflows at two USGS streamgages on Johnson Creek) and validated with data from the flood of January 2009. Results were typically within 0.6 foot (ft) of recorded or measured water-surface elevations from the December 2015 flood, and within 0.8 ft from the January 2009 flood. Output from the hydraulic model was used to create eight flood inundation maps ranging in stage from 9 to 16 ft. Boundary condition hydrographs were identical in shape to those from the December 2015 flood event, but were scaled up or down to produce the amount of streamflow corresponding to a specific water-surface elevation at the Sycamore streamgage (14211500). Sensitivity analyses using other hydrograph shapes, and a version of the model in which the peak flow is maintained for an extended period of time, showed minimal variation, except for overbank areas near the Foster Floodplain Natural Area.Simulated water-surface profiles were combined with light detection and ranging (lidar) data collected in 2014 to delineate water-surface extents for each of the eight modeled stages. The availability of flood-inundation maps in conjunction with real-time data from the USGS streamgages along Johnson Creek and forecasted hydrographs from the National Weather Service Northwest River Forecast Center will provide residents of the watershed and emergency management personnel with valuable information that may aid in flood response, including potential evacuations, road closures, and mitigation efforts. In addition, these maps may be used for post-flood recovery efforts.

76 FR 72627 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

.... confluence with Black Fox Run. Approximately 480 feet +868 upstream of State Route 368. Allegheny River... Assistance No. 97.022, ``Flood Insurance.'' Dated: November 14, 2011. Sandra K. Knight, Deputy Associate...

75 FR 78650 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-16

..., Mississippi, and Incorporated Areas Big Black River Approximately 21.9 None +149 Unincorporated Areas of miles.... 97.022, ``Flood Insurance.'') Dated: December 3, 2010. Sandra K. Knight, Deputy Federal Insurance and...

18 CFR 415.43 - Mapped and unmapped delineations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... data submitted, soil surveys, historic flood maps, high water marks and other empirical data, the... establish the flood protection elevation for the particular site. (c) Pending the preparation and completion...

18 CFR 415.43 - Mapped and unmapped delineations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... data submitted, soil surveys, historic flood maps, high water marks and other empirical data, the... establish the flood protection elevation for the particular site. (c) Pending the preparation and completion...

44 CFR 67.12 - Appeal to District Court.

Code of Federal Regulations, 2014 CFR

2014-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.12 Appeal to District Court. (a) An appellant aggrieved by the...

44 CFR 67.12 - Appeal to District Court.

Code of Federal Regulations, 2012 CFR

2012-10-01

... OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.12 Appeal to District Court. (a) An appellant aggrieved by the...

Development of a flood-warning network and flood-inundation mapping for the Blanchard River in Ottawa, Ohio

USGS Publications Warehouse

Whitehead, Matthew T.

2011-01-01

Digital flood-inundation maps of the Blanchard River in Ottawa, Ohio, were created by the U.S. Geological Survey (USGS) in cooperation with the U.S. Department of Agriculture, Natural Resources Conservation Service and the Village of Ottawa, Ohio. The maps, which correspond to water levels (stages) at the USGS streamgage at Ottawa (USGS streamgage site number 04189260), were provided to the National Weather Service (NWS) for incorporation into a Web-based flood-warning Network that can be used in conjunction with NWS flood-forecast data to show areas of predicted flood inundation associated with forecasted flood-peak stages. Flood profiles were computed by means of a step-backwater model calibrated to recent field measurements of streamflow. The step-backwater model was then used to determine water-surface-elevation profiles for 12 flood stages with corresponding streamflows ranging from less than the 2-year and up to nearly the 500-year recurrence-interval flood. The computed flood profiles were used in combination with digital elevation data to delineate flood-inundation areas. Maps of the Village of Ottawa showing flood-inundation areas overlain on digital orthophotographs are presented for the selected floods. As part of this flood-warning network, the USGS upgraded one streamgage and added two new streamgages, one on the Blanchard River and one on Riley Creek, which is tributary to the Blanchard River. The streamgage sites were equipped with both satellite and telephone telemetry. The telephone telemetry provides dual functionality, allowing village officials and the public to monitor current stage conditions and enabling the streamgage to call village officials with automated warnings regarding flood stage and/or predetermined rates of stage increase. Data from the streamgages serve as a flood warning that emergency management personnel can use in conjunction with the flood-inundation maps by to determine a course of action when flooding is imminent.

Floods of May 2006 and April 2007 in Southern Maine

USGS Publications Warehouse

Lombard, Pamela J.

2009-01-01

The U.S. Geological Survey Maine Water Science Center has worked with the Federal Emergency Management Agency for decades to document the magnitude and extent of major floods in Maine. Reports describing the May 2006 and April 2007 floods in southern Maine are examples of this cooperative relationship. The documentation of peak stream elevations and peak streamflow magnitudes and recurrence intervals provides essential information for the delineation of flood plains and for flood-mitigation decisions by local, State, and Federal emergency management officials.

River flood plains: Some observations on their formation

USGS Publications Warehouse

Wolman, M. Gordon; Leopold, Luna Bergere

1957-01-01

On many small rivers and most great rivers, the flood plain consists of channel and overbank deposits. The proportion of the latter is generally very small.Frequency studies indicate that the flood plains of many streams of different sizes flowing in diverse physiographic and climatic regions are subject to flooding about once a year.The uniform frequency of flooding of the flood-plain surface and the small amount of deposition observed in great floods (average 0.07 foot) support the conclusion that overbank deposition contributes only a minor part of the material constituting the flood plain. The relatively high velocities (1 to 4 fps) which can occur in overbank flows and the reduction in sediment concentration which often accompanies large floods may also help account for this. Although lateral migration of channels is important in controlling the elevation of the flood plain, rates of migration are extremely variable and alone cannot account for the uniform relation the flood-plain surface bears to the channel.Detailed studies of flood plains in Maryland and in North Carolina indicate that it is difficult to differentiate between channel and overbank deposits in a stratigraphic section alone.Because deposition on the flood plain does not continue indefinitely, the flood-plain surface can only be transformed into a terrace surface by some tectonic or climatic change which alters the regimen of the river and causes it to entrench itself below its established bed and associated flood plain. A terrace, then, is distinguished from a flood plain by the frequency with which each is overflowed.

Impacts of flood damage on airborne bacteria and fungi in homes after the 2013 Colorado Front Range flood.

PubMed

Emerson, Joanne B; Keady, Patricia B; Brewer, Tess E; Clements, Nicholas; Morgan, Emily E; Awerbuch, Jonathan; Miller, Shelly L; Fierer, Noah

2015-03-03

Flood-damaged homes typically have elevated microbial loads, and their occupants have an increased incidence of allergies, asthma, and other respiratory ailments, yet the microbial communities in these homes remain under-studied. Using culture-independent approaches, we characterized bacterial and fungal communities in homes in Boulder, CO, USA 2-3 months after the historic September, 2013 flooding event. We collected passive air samples from basements in 50 homes (36 flood-damaged, 14 non-flooded), and we sequenced the bacterial 16S rRNA gene (V4-V5 region) and the fungal ITS1 region from these samples for community analyses. Quantitative PCR was used to estimate the abundances of bacteria and fungi in the passive air samples. Results indicate significant differences in bacterial and fungal community composition between flooded and non-flooded homes. Fungal abundances were estimated to be three times higher in flooded, relative to non-flooded homes, but there were no significant differences in bacterial abundances. Penicillium (fungi) and Pseudomonadaceae and Enterobacteriaceae (bacteria) were among the most abundant taxa in flooded homes. Our results suggest that bacterial and fungal communities continue to be affected by flooding, even after relative humidity has returned to baseline levels and remediation has removed any visible evidence of flood damage.

Can elevated CO2 modify regeneration from seed banks of floating freshwater marshes subjected to rising sea-level?

USGS Publications Warehouse

Middleton, Beth A.; McKee, Karen L.

2012-01-01

Higher atmospheric concentrations of CO2 can offset the negative effects of flooding or salinity on plant species, but previous studies have focused on mature, rather than regenerating vegetation. This study examined how interacting environments of CO2, water regime, and salinity affect seed germination and seedling biomass of floating freshwater marshes in the Mississippi River Delta, which are dominated by C3 grasses, sedges, and forbs. Germination density and seedling growth of the dominant species depended on multifactor interactions of CO2 (385 and 720 μl l-1) with flooding (drained, +8-cm depth, +8-cm depth-gradual) and salinity (0, 6% seawater) levels. Of the three factors tested, salinity was the most important determinant of seedling response patterns. Species richness (total = 19) was insensitive to CO2. Our findings suggest that for freshwater marsh communities, seedling response to CO2 is species-specific and secondary to salinity and flooding effects. Elevated CO2 did not ameliorate flooding or salinity stress. Consequently, climate-related changes in sea level or human-caused alterations in hydrology may override atmospheric CO2 concentrations in driving shifts in this plant community. The results of this study suggest caution in making extrapolations from species-specific responses to community-level predictions without detailed attention to the nuances of multifactor responses.

Visual Sensing for Urban Flood Monitoring

PubMed Central

Lo, Shi-Wei; Wu, Jyh-Horng; Lin, Fang-Pang; Hsu, Ching-Han

2015-01-01

With the increasing climatic extremes, the frequency and severity of urban flood events have intensified worldwide. In this study, image-based automated monitoring of flood formation and analyses of water level fluctuation were proposed as value-added intelligent sensing applications to turn a passive monitoring camera into a visual sensor. Combined with the proposed visual sensing method, traditional hydrological monitoring cameras have the ability to sense and analyze the local situation of flood events. This can solve the current problem that image-based flood monitoring heavily relies on continuous manned monitoring. Conventional sensing networks can only offer one-dimensional physical parameters measured by gauge sensors, whereas visual sensors can acquire dynamic image information of monitored sites and provide disaster prevention agencies with actual field information for decision-making to relieve flood hazards. The visual sensing method established in this study provides spatiotemporal information that can be used for automated remote analysis for monitoring urban floods. This paper focuses on the determination of flood formation based on image-processing techniques. The experimental results suggest that the visual sensing approach may be a reliable way for determining the water fluctuation and measuring its elevation and flood intrusion with respect to real-world coordinates. The performance of the proposed method has been confirmed; it has the capability to monitor and analyze the flood status, and therefore, it can serve as an active flood warning system. PMID:26287201

33 CFR 208.34 - Norman Dam and Lake Thunderbird, Little River, Okla.

Code of Federal Regulations, 2011 CFR

2011-07-01

... amounts to 76,600 acre-feet. Whenever the reservoir level is within this elevation range the flood control... flood damage below the reservoir. In order to accomplish this purpose, flood control releases shall be... of bankfull on the Little River downstream of the reservoir. Controlling bankfull stages and...

33 CFR 208.34 - Norman Dam and Lake Thunderbird, Little River, Okla.

Code of Federal Regulations, 2010 CFR

2010-07-01

... amounts to 76,600 acre-feet. Whenever the reservoir level is within this elevation range the flood control... flood damage below the reservoir. In order to accomplish this purpose, flood control releases shall be... of bankfull on the Little River downstream of the reservoir. Controlling bankfull stages and...

A Coupled Community-Level Assessment of Social and Physical Vulnerability to Hurricane Disasters

NASA Astrophysics Data System (ADS)

Kim, J. H.; Sutley, E. J.; Chowdhury, A. G.; Hamideh, S.

2017-12-01

A significant portion of the U.S. building inventory exists in hurricane- and flood-prone regions. The accompanying storm surge and rising water levels often result in the inundation of residential homes, particularly those occupied by low income households and forcing displacement. In order to mitigate potential damages, a popular design technique is to elevate the structure using piers or piles to above the base flood elevation. This is observed for single-family and multi-family homes, including manufactured homes and post-disaster temporary housing, albeit at lower elevations. Although this design alleviates potential flood damage, it affects the wind-structure interaction by subjecting the structure to higher wind speeds due to its increased height and also having a path for the wind to pass underneath the structure potentially creating new vulnerabilities to wind loading. The current ASCE 7 Standard (2016) does not include a methodology for addressing the modified aerodynamics and estimating wind loads for elevated structures, and thus the potential vulnerability during high wind events is unaccounted for in design. Using experimentally measured wind pressures on elevated and non-elevated residential building models, tax data, and census data, a coupled vulnerability assessment is performed at the community-level. Galveston, Texas is selected as the case study community. Using the coupled assessment model, a hindcast of 2008 Hurricane Ike is used for predicting physical damage and household dislocation. The predicted results are compared with the actual outcomes of the 2008 hurricane disaster. Recommendations are made (1) for code adoption based on the experimentally measured wind loads, and (2) for mitigation actions and policies that would could decrease population dislocation and promote recovery.

77 FR 46980 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-07

... Executive Order 12988. List of Subjects in 44 CFR Part 67 Administrative practice and procedure, Flood... upstream of Northeast 152nd Avenue. Whipple Creek Just downstream of +28 Unincorporated Areas of Northwest...

44 CFR 68.10 - Burden of proof.

Code of Federal Regulations, 2013 CFR

2013-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES § 68.10 Burden of proof. The burden shall be on appellant(s) to prove that the flood elevation...

44 CFR 68.10 - Burden of proof.

Code of Federal Regulations, 2011 CFR

2011-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES § 68.10 Burden of proof. The burden shall be on appellant(s) to prove that the flood elevation...

44 CFR 68.10 - Burden of proof.

Code of Federal Regulations, 2010 CFR

2010-10-01

... HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program ADMINISTRATIVE HEARING PROCEDURES § 68.10 Burden of proof. The burden shall be on appellant(s) to prove that the flood elevation...

Temporal and spatial variability in thalweg profiles of a gravel-bed river

USGS Publications Warehouse

Madej, Mary Ann

1999-01-01

This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths, percentage of channel length occupied by riffles, and a spatial autocorrelation coefficient (Moran's I) were used to quantify changes in morphological diversity and spatial structure in Redwood Creek basin, northwestern California. Bed topography in Redwood Creek and its major tributaries consists primarily of a series of pools and riffles. The size, frequency and spatial distribution of the pools and riffles have changed significantly during the past 20 years. Following large floods and high sediment input in Redwood Creek and its tributaries in 1975, variation in channel bed elevations was low and the percentage of the channel length occupied by riffles was high. Over the next 20 years, variation in bed elevations increased while the length of channel occupied by riffles decreased. An index [(standard deviation of residual water depth/bankfull depth) × 100] was developed to compare variations in bed elevation over a range of stream sizes, with a higher index being indicative of greater morphological diversity. Spatial autocorrelation in the bed elevation data was apparent at both fine and coarse scales in many of the thalweg profiles and the observed spatial pattern of bed elevations was found to be related to the dominant channel material and the time since disturbance. River reaches in which forced pools dominated, and in which large woody debris and bed particles could not be easily mobilized, exhibited a random distribution of bed elevations. In contrast, in reaches where alternate bars dominated, and both wood and gravel were readily transported, regularly spaced bed topography developed at a spacing that increased with time since disturbance. This pattern of regularly spaced bed features was reversed following a 12-year flood when bed elevations became more randomly arranged.

Regional skew for California, and flood frequency for selected sites in the Sacramento-San Joaquin River Basin, based on data through water year 2006

USGS Publications Warehouse

Parrett, Charles; Veilleux, Andrea; Stedinger, J.R.; Barth, N.A.; Knifong, Donna L.; Ferris, J.C.

2011-01-01

Improved flood-frequency information is important throughout California in general and in the Sacramento-San Joaquin River Basin in particular, because of an extensive network of flood-control levees and the risk of catastrophic flooding. A key first step in updating flood-frequency information is determining regional skew. A Bayesian generalized least squares (GLS) regression method was used to derive a regional-skew model based on annual peak-discharge data for 158 long-term (30 or more years of record) stations throughout most of California. The desert areas in southeastern California had too few long-term stations to reliably determine regional skew for that hydrologically distinct region; therefore, the desert areas were excluded from the regional skew analysis for California. Of the 158 long-term stations used to determine regional skew, 145 have minimally regulated annual-peak discharges, and 13 stations are dam sites for which unregulated peak discharges were estimated from unregulated daily maximum discharge data furnished by the U.S. Army Corp of Engineers. Station skew was determined by using an expected moments algorithm (EMA) program for fitting the Pearson Type 3 flood-frequency distribution to the logarithms of annual peak-discharge data. The Bayesian GLS regression method previously developed was modified because of the large cross correlations among concurrent recorded peak discharges in California and the use of censored data and historical flood information with the new expected moments algorithm. In particular, to properly account for these cross-correlation problems and develop a suitable regression model and regression diagnostics, a combination of Bayesian weighted least squares and generalized least squares regression was adopted. This new methodology identified a nonlinear function relating regional skew to mean basin elevation. The regional skew values ranged from -0.62 for a mean basin elevation of zero to 0.61 for a mean basin elevation of 11,000 feet. This relation between skew and elevation reflects the interaction of snow with rain, which increases with increased elevation. The equivalent record length for the new regional skew ranges from 52 to 65 years of record, depending upon mean basin elevation. The old regional skew map in Bulletin 17B, published by the Hydrology Subcommittee of the Interagency Advisory Committee on Water Data (1982), reported an equivalent record length of only 17 years. The newly developed regional skew relation for California was used to update flood frequency for the 158 sites used in the regional skew analysis as well as 206 selected sites in the Sacramento-San Joaquin River Basin. For these sites, annual-peak discharges having recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years were determined on the basis of data through water year 2006. The expected moments algorithm was used for determining the magnitude and frequency of floods at gaged sites by using regional skew values and using the basic approach outlined in Bulletin

Designing a Software for Flood Risk Assessment Based on Multi Criteria Desicion Analysis and Information Diffusion Methods

NASA Astrophysics Data System (ADS)

Musaoglu, N.; Saral, A.; Seker, D. Z.

2012-12-01

Flooding is one of the major natural disasters not only in Turkey but also in all over the world and it causes serious damage and harm. It is estimated that of the total economic loss caused by all kinds of disasters, 40% was due to floods. In July 1995, the Ayamama Creek in Istanbul was flooded, the insurance sector received around 1,200 claims notices during that period, insurance companies had to pay a total of $40 million for claims. In 2009, the same creek was flooded again and killed 31 people over two days and insurance firms paid for damages around cost €150 million for claims. To solve these kinds of problems modern tools such as GIS and Remote Sensing should be utilized. In this study, a software was designed for the flood risk analysis with Analytic Hierarchy Process (AHP) and Information Diffusion( InfoDif) methods.In the developed sofware, five evaluation criterias were taken into account, which were slope, aspect, elevation, geology and land use which were extracted from the satellite sensor data. The Digital Elevation Model (DEM) of the Ayamama River Basin was acquired from the SPOT 5 satellite image with 2.5 meter spatial resolution. Slope and aspect values of the study basin were extracted from this DEM. The land use of the Ayamama Creek was obtained by performing object-oriented nearest neighbor classification method by image segmentation on SPOT 5 image dated 2010. All produced data were used as an input for the part of Multi Criteria Desicion Analysis (MCDA) method of this software. Criterias and their each sub criteras were weighted and flood vulnerability was determined with MCDA-AHP. Also, daily flood data was collected from Florya Meteorological Station, between 1975 to 2009 years and the daily flood peak discharge was calculated with the method of Soil Conservation Service-Curve Number (SCS-CN) and were used as an input in the software for the part of InfoDif.Obtained results were verified using ground truth data and it has been clearly seen that the developed (TRA) software which uses two different methods for flood risk analysis, can be more effective for achieving different decision problems, from conventional techniques and produce more reliable results in a short time.; Study Area

75 FR 3885 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-25

... meters (MSL) Effective Modified Napa County, California, and Incorporated Areas Napa Creek At the... flooding area, +17 2 approximately 1,400 feet northeast of intersection of Imola Avenue and Gasser Drive... meter. [[Page 3886

76 FR 40815 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-12

..., 2010 460046 1172). 08-0269P). November 17, 2010; Krambeck, Mayor, City of The Black Hills Spearfish... Assistance No. 97.022, ``Flood Insurance.'') Dated: June 15, 2011 Sandra K. Knight, Deputy Federal Insurance...

77 FR 6980 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-10

... feet above ground [caret] Elevation in meters (MSL) Modified Unincorporated Areas of Nowata County... Sea Level, rounded to the nearest 0.1 meter. ADDRESSES Unincorporated Areas of Nowata County Maps are... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified St. Lucie County...

77 FR 3625 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-25

... feet above ground [caret] Elevation in meters (MSL) Modified City of Baltimore, Maryland Docket No... Sea Level, rounded to the nearest 0.1 meter. ADDRESSES City of Baltimore Maps are available for... Depth in feet Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified...

Applications of Radarsat-1 synthetic aperture radar imagery to assess hurricane-related flooding of coastal Louisiana

USGS Publications Warehouse

Kiage, L.M.; Walker, N.D.; Balasubramanian, S.; Babin, A.; Barras, J.

2005-01-01

The Louisiana coast is subjected to hurricane impacts including flooding of human settlements, river channels and coastal marshes, and salt water intrusion. Information on the extent of flooding is often required quickly for emergency relief, repairs of infrastructure, and production of flood risk maps. This study investigates the feasibility of using Radarsat-1 SAR imagery to detect flooded areas in coastal Louisiana after Hurricane Lili, October 2002. Arithmetic differencing and multi-temporal enhancement techniques were employed to detect flooding and to investigate relationships between backscatter and water level changes. Strong positive correlations (R2=0.7-0.94) were observed between water level and SAR backscatter within marsh areas proximate to Atchafalaya Bay. Although variations in elevation and vegetation type did influence and complicate the radar signature at individual sites, multi-date differences in backscatter largely reflected the patterns of flooding within large marsh areas. Preliminary analyses show that SAR imagery was not useful in mapping urban flooding in New Orleans after Hurricane Katrina's landfall on 29 August 2005. ?? 2005 Taylor & Francis.

Intercomparison of DEM-based approaches for the identification of flood-prone areas in different geomorphologic and climatic conditions

NASA Astrophysics Data System (ADS)

Samela, Caterina; Nardi, Fernando; Grimaldi, Salvatore; De Paola, Francesco; Sole, Aurelia; Manfreda, Salvatore

2014-05-01

Floods represent the most critical natural hazard for many countries and their frequency appears to be increasing in recent times. The legal constraints of public administrators and the growing interest of private companies (e.g., insurance companies) in identifying the areas exposed to the flood risk, is determining the necessity of developing new tools for the risk classification over large areas. Nowadays, among the numerous hydrologic and hydraulic methods regularly used for practical applications, 2-D hydraulic modeling represents the most accurate approach for deriving detailed inundation maps. Nevertheless, data requirement for these modeling approaches is certainly onerous, limiting their applicability over large areas. On this issue, the terrain morphology may provide an extraordinary amount of information useful to detect areas that are particularly prone to serious flooding. In the present work, we compare the reliability of different DEM-derived quantitative morphologic descriptors in characterizing the relationships between geomorphic attributes and flood exposure. The tests are carried out using techniques of pattern classification, such as linear binary classifiers (Degiorgis et al., 2012), whose ability is evaluated through performance measures. Simple and composed morphologic features are taken into account. The morphological features are: the upslope contributing area (A), the local slope (S), the length of the path that hydrologically connects the location under exam to the nearest element of the drainage network (D), the difference in elevation between the cell under exam and the final point of the same path (H), the curvature (downtriangle2H). In addition to the mentioned features, the study takes into consideration a number of composed indices, such as: the modified topographic index (Manfreda et al., 2011), the downslope index (DI) proposed by Hjerdt et al. (2004), the ratio between the elevation difference H and the distance to the network D, and other indices. Each binary classifier is applied in several catchments in order to verify the reproducibility of the procedures in different geomorphologic, climatic and hydrologic conditions. The study explores the use of these procedures in gauged river basins located in Italy and in an ungauged basin located in Africa. References Degiorgis, M., G. Gnecco, S. Gorni, G. Roth, M. Sanguineti, A.C. Taramasso, 2012. Classifiers for the detection of flood-prone areas using remote sensed elevation data, J. Hydrol., 470-471, 302-315. Hjerdt, K. N., J.J. McDonnell, J. Seibert, A. Rodhe, A new topographic index to quantify downslope controls on local drainage, Water Resour. Res., 40, W05602, 2004. Manfreda, S., M. Di Leo, A. Sole, Detection of Flood Prone Areas using Digital Elevation Models, J. Hydrol. Eng., 16(10), 781-790, 2011.

Changes in carbohydrate content and membrane stability of two ecotypes of Calamagrostis arundinacea growing at different elevations in the drawdown zone of the Three Gorges Reservoir.

PubMed

Lei, Shutong; Zeng, Bo; Yuan, Zhi; Su, Xiaolei

2014-01-01

The Three Gorges project has caused many ecosystem problems. Ecological restoration using readily-available plants is an effective way of mitigating environmental impacts. Two perennial submergence-tolerant ecotypes of Calamagrostis arundinacea were planted in an experimental field in the drawdown zone. Responses of the two plant ecotypes to flooding stress in the drawdown zone were unknown. Carbohydrate content and membrane stability, two key factors for survival of plants under flooding stress, of two ecotypes (designated "dwarf" and "green") of C. arundinacea growing at different elevations of the drawdown zone were investigated. Live stems (LS) and dead stems (DS) of the two plant ecotypes at eight elevations (175, 170, 162, 160, 158, 155, 152 m and 149 m) were sampled. Contents of soluble sugar, starch and malondialdehyde (MDA), as well as plasma membrane permeability of live stems were measured. The lowest elevations for survival of dwarf and green C. arundinacea were 160 m and 158 m, respectively. Soluble sugar content of live stems of both ecotypes decreased with elevation, with amounts from an elevation of 170 m being lower than from an elevation of 175 m. MDA content and plasma membrane permeability in live stems of green C. arundinacea did not increase with the decrease in elevation, while these measures in dwarf C. arundinacea from an elevation of 162 m were significantly higher than from an elevation of 175 m. Carbohydrate content, especially soluble sugar content, in both ecotypes was more sensitive to flooding stress than membrane stability. Green C. arundinacea had a higher tolerance to submergence than dwarf C. arundinacea, and thus green C. arundinacea can be planted at lower elevations than dwarf C. arundinacea.

Preliminary estimate of possible flood elevations in the Columbia River at Trojan Nuclear Power Plant due to failure of debris dam blocking Spirit Lake, Washington

USGS Publications Warehouse

Kresch, D.L.; Laenen, Antonius

1984-01-01

Failure of the debris dam, blocking the outflow of Spirit Lake near Mount St. Helens, could result in a mudflow down the Toutle and Cowlitz Rivers into the Columbia River. Flood elevations at the Trojan Nuclear Power Plant on the Columbia River, 5 mi upstream from the Cowlitz River, were simulated with a hydraulic routing model. The simulations are made for four Columbia River discharges in each of two scenarios, one in which Columbia River floods coincide with a mudflow and the other in which Columbia River floods follow a mudflow sediment deposit upstream from the Cowlitz River. In the first scenario, Manning 's roughness coefficients for clear water and for mudflow in the Columbia River are used; in the second scenario only clear water coefficients are used. The grade elevation at the power plant is 45 ft above sea level. The simulated elevations exceed 44 ft if the mudflow coincides with a Columbia River discharge that has a recurrence interval greater than 10 years (610,000 cu ft/sec); the mudflow is assumed to extend downstream from the Cowlitz River to the mouth of the Columbia River, and Manning 's roughness coefficients for a mudflow are used. The simulated elevation is 32 ft if the mudflow coincides with a 100-yr flood (820,000 cu ft/sec) and clear-water Manning 's coefficients are used throughout the entire reach of the Columbia River. The elevations exceed 45 ft if a flow exceeding the 2-yr peak discharge in the Columbia River (410,000 cu ft/sec) follows the deposit of 0.5 billion cu yd of mudflow sediment upstream of the Cowlitz River before there has been any appreciable scour or dredging of the deposit. In this simulation it is assumed that: (1) the top of the sediment deposited in the Columbia River is at an elevation of 30 ft at the mouth of the Cowlitz River, (2) the surface elevation of the sediment deposit decreases in an upstream direction at a rate of 2.5 ft/mi, and (3) clear water Manning 's coefficients apply to the entire modeled reach of the Columbia River. (Author 's abstract)

A large-scale simulation of climate change effects on flood regime - A case study for the Alabama-Coosa-Tallapoosa River Basin

NASA Astrophysics Data System (ADS)

Dullo, T. T.; Gangrade, S.; Marshall, R.; Islam, S. R.; Ghafoor, S. K.; Kao, S. C.; Kalyanapu, A. J.

2017-12-01

The damage and cost of flooding are continuously increasing due to climate change and variability, which compels the development and advance of global flood hazard models. However, due to computational expensiveness, evaluation of large-scale and high-resolution flood regime remains a challenge. The objective of this research is to use a coupled modeling framework that consists of a dynamically downscaled suite of eleven Coupled Model Intercomparison Project Phase 5 (CMIP5) climate models, a distributed hydrologic model called DHSVM, and a computational-efficient 2-dimensional hydraulic model called Flood2D-GPU to study the impacts of climate change on flood regime in the Alabama-Coosa-Tallapoosa (ACT) River Basin. Downscaled meteorologic forcings for 40 years in the historical period (1966-2005) and 40 years in the future period (2011-2050) were used as inputs to drive the calibrated DHSVM to generate annual maximum flood hydrographs. These flood hydrographs along with 30-m resolution digital elevation and estimated surface roughness were then used by Flood2D-GPU to estimate high-resolution flood depth, velocities, duration, and regime. Preliminary results for the Conasauga river basin (an upper subbasin within ACT) indicate that seven of the eleven climate projections show an average increase of 25 km2 in flooded area (between historic and future projections). Future work will focus on illustrating the effects of climate change on flood duration and area for the entire ACT basin.

Assessment of the Flood Problems of the Taunton River Basin Massachusetts.

DTIC Science & Technology

1978-12-01

essential for fish and provides a habitat for numerous varieties of aquatic oriented wildlife species. Of the com- bined forested wetland and open forest...Detailed flood elevation data essential for operation of regula- tions. Flood velocities, flood duration, wave action, erosion pr,,- blems and other...along with the preservation of as much trees and shrubs are essential . Where possible fast growing annual grass seed should be used, intermixed with

The Impact of the Extreme Amazonian Flood Season on the Incidence of Viral Gastroenteritis Cases.

PubMed

Vieira, Carmen Baur; de Abreu Corrêa, Adriana; de Jesus, Michele Silva; Luz, Sérgio Luiz Bessa; Wyn-Jones, Peter; Kay, David; Rocha, Mônica Simões; Miagostovich, Marize Pereira

2017-06-01

During the Amazonian flood season in 2012, the Negro River reached its highest level in 110 years, submerging residential and commercial areas which appeared associated with an elevation in the observed gastroenteritis cases in the city of Manaus. The aim of this study was to evaluate the microbiological water quality of the Negro River basin during this extreme flood to investigate this apparent association between the illness cases and the population exposed to the contaminated waters. Forty water samples were collected and analysed for classic and emerging enteric viruses. Human adenoviruses, group A rotaviruses and genogroup II noroviruses were detected in 100, 77.5 and 27.5% of the samples, respectively, in concentrations of 10 3 -10 6 GC/L. All samples were compliant with local bacteriological standards. HAdV2 and 41 and RVA G2, P[6], and P[8] were characterised. Astroviruses, sapoviruses, genogroup IV noroviruses, klasseviruses, bocaviruses and aichiviruses were not detected. Statistical analyses showed correlations between river stage level and reported gastroenteritis cases and, also, significant differences between virus concentrations during this extreme event when compared with normal dry seasons and previous flood seasons of the Negro River. These findings suggest an association between the extreme flood experienced and gastrointestinal cases in the affected areas providing circumstantial evidence of causality between the elevations in enteric viruses in surface waters and reported illness.

75 FR 78613 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-16

... Flood Disaster Protection Act of 1973, 42 U.S.C. 4105, and are in accordance with the National Flood Insurance Act of 1968, 42 U.S.C. 4001 et seq., and with 44 CFR part 65. For rating purposes, the currently... within the scope of the Regulatory Flexibility Act, 5 U.S.C. 601- 612, a regulatory flexibility analysis...

Flood Study of Warren Brook in Alstead and Cold River in Alstead, Langdon, and Walpole, New Hampshire, 2005

USGS Publications Warehouse

Flynn, Robert H.

2006-01-01

This report presents water-surface elevations and profiles as determined using the U.S. Army Corps of Engineers (USACE) one-dimensional Hydrologic Engineering Center River Analysis System, also known as HEC-RAS. Steady flow water-surface profiles were developed for two stream reaches: the Cold River from its confluence with the Connecticut River in Walpole, through Alstead to the McDermott Bridge in Langdon, NH, and Warren Brook from its confluence with the Cold River to Warren Lake in Alstead, NH. Flood events of a magnitude, which are expected to be equaled or exceeded once on the average during any 10-, 50-, 100-, or 500-year period (recurrence interval), were modeled using HEC-RAS as these flood events are recognized as being significant for flood-plain management, determination of flood insurance rates, and design of structures such as bridges and culverts. These flood events are referred to as the 10-, 50-, 100-, and 500-year floods and have a 10-, 2-, 1-, and 0.2-percent chance, respectively, of being equaled or exceeded during any year. The recurrence intervals represent the long-term average between floods of a specific magnitude. The risk of experiencing rare floods at short intervals or within the same year increases when periods greater than one year are considered. The analyses in this study reflect the flooding potentials based on conditions existing in the communities of Walpole, Alstead and Langdon at the time of completion of this study.

Integrating Entropy-Based Naïve Bayes and GIS for Spatial Evaluation of Flood Hazard.

PubMed

Liu, Rui; Chen, Yun; Wu, Jianping; Gao, Lei; Barrett, Damian; Xu, Tingbao; Li, Xiaojuan; Li, Linyi; Huang, Chang; Yu, Jia

2017-04-01

Regional flood risk caused by intensive rainfall under extreme climate conditions has increasingly attracted global attention. Mapping and evaluation of flood hazard are vital parts in flood risk assessment. This study develops an integrated framework for estimating spatial likelihood of flood hazard by coupling weighted naïve Bayes (WNB), geographic information system, and remote sensing. The north part of Fitzroy River Basin in Queensland, Australia, was selected as a case study site. The environmental indices, including extreme rainfall, evapotranspiration, net-water index, soil water retention, elevation, slope, drainage proximity, and density, were generated from spatial data representing climate, soil, vegetation, hydrology, and topography. These indices were weighted using the statistics-based entropy method. The weighted indices were input into the WNB-based model to delineate a regional flood risk map that indicates the likelihood of flood occurrence. The resultant map was validated by the maximum inundation extent extracted from moderate resolution imaging spectroradiometer (MODIS) imagery. The evaluation results, including mapping and evaluation of the distribution of flood hazard, are helpful in guiding flood inundation disaster responses for the region. The novel approach presented consists of weighted grid data, image-based sampling and validation, cell-by-cell probability inferring and spatial mapping. It is superior to an existing spatial naive Bayes (NB) method for regional flood hazard assessment. It can also be extended to other likelihood-related environmental hazard studies. © 2016 Society for Risk Analysis.

44 CFR 67.9 - Final determination in the absence of an appeal by the community.

Code of Federal Regulations, 2012 CFR

2012-10-01

... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.9 Final determination in the...

44 CFR 67.9 - Final determination in the absence of an appeal by the community.

Code of Federal Regulations, 2014 CFR

2014-10-01

... EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION DETERMINATIONS § 67.9 Final determination in the...

Using Remote Sensing and High-Resolution Digital Elevation Models to Identify Potential Erosional Hotspots Along River Channels During High Discharge Storm Events

NASA Astrophysics Data System (ADS)

Orland, E. D.; Amidon, W. H.

2017-12-01

As global warming intensifies, large precipitation events and associated floods are becoming increasingly common. Channel adjustments during floods can occur by both erosion and deposition of sediment, often damaging infrastructure in the process. There is thus a need for predictive models that can help managers identify river reaches that are most prone to adjustment during storms. Because rivers in post-glacial landscapes often flow over a mixture of bedrock and alluvial substrates, the identification of bedrock vs. alluvial channel reaches is an important first step in predicting vulnerability to channel adjustment during flood events, especially because bedrock channels are unlikely to adjust significantly, even during floods. This study develops a semi-automated approach to predicting channel substrate using a high-resolution LiDAR-derived digital elevation model (DEM). The study area is the Middlebury River in Middlebury, VT-a well-studied watershed with a wide variety of channel substrates, including reaches with documented channel adjustments during recent flooding events. Multiple metrics were considered for reference—such as channel width and drainage area—but the study utilized channel slope as a key parameter for identifying morphological variations within the Middlebury River. Using data extracted from the DEM, a power law was fit to selected slope and drainage area values for each branch in order to model idealized slope-drainage area relationships, which were then compared with measured slope-drainage area relationships. Differences in measured slope minus predicted slope (called delta-slope) are shown to help predict river channel substrate. Compared with field observations, higher delta-slope values correlate with more stable, boulder rich channels or bedrock gorges; conversely the lowest delta-slope values correlate with flat, sediment rich alluvial channels. The delta-slope metric thus serves as a reliable first-order predictor of channel substrate in the Middlebury River, which in turn can be used to help identify local reaches that are most vulnerable to channel adjustment during large flood events.

Flood-inundation maps for Lake Champlain in Vermont and in northern Clinton County, New York

USGS Publications Warehouse

Flynn, Robert H.; Hayes, Laura

2016-06-30

Digital flood-inundation maps for an approximately100-mile length of Lake Champlain in Addison, Chittenden, Franklin, and Grand Isle Counties in Vermont and northern Clinton County in New York were created by the U.S. Geological Survey (USGS) in cooperation with the International Joint Commission (IJC). The flood-inundationmaps, which can be accessed through the International Joint Commission (IJC) Web site at http://www.ijc.org/en_/, depict estimates of the areal extent flooding correspondingto selected water levels (stages) at the USGS lake gage on the Richelieu River (Lake Champlain) at Rouses Point, N.Y. (station number 04295000). In this study, wind and seiche effects (standing oscillating wave with a long wavelength) were not taken into account and the flood-inundation mapsreflect 11 stages (elevations) for Lake Champlain that are static for the study length of the lake. Near-real-time stages at this lake gage, and others on Lake Champlain, may be obtained on the Internet from the USGS National Water Information System at http://waterdata.usgs.gov/ or the National Weather Service Advanced Hydrologic Prediction Service at http:/water.weather.gov/ahps/, which also forecasts flood hydrographs at the Richelieu River (Lake Champlain) at Rouses Point.Static flood boundary extents were determined for LakeChamplain in Addison, Chittenden, Franklin, and Grand Isle Counties in Vermont and northern Clinton County in New York using recently acquired (2013–2014) lidar (light detection and ranging) and may be referenced to any of the five USGS lake gages on Lake Champlain. Of these five lakgages, USGS lake gage 04295000, Richelieu River (Lake Champlain) at Rouses Point, N.Y., is the only USGS lake gage that is also a National Weather Service prediction location. Flood boundary extents for the Lake Champlain static flood-inundation map corresponding to the May 201 flood(103.2 feet [ft], National Geodetic Vertical Datum [NGVD] 29) were evaluated by comparing these boundary extents against the inundation area extents determined for the May 2011 flood (which incorporated documented high-water marksfrom the flood of May 201) (Bjerklie and others, 2014).A digital elevation model (DEM) was created by USGS, within a geographic information system (GIS), from the recently flown and processed light detection and ranging(lidar) data (2013–2014) in Vermont and the lake shore area of northern Clinton County in New York. The lidar data have a vertical accuracy of 0.3 to 0.6-ft (9.6 to 18.0-centimeters [cm]) and a horizontal resolution of 2.3 to 4.6 ft (0.7 to 1.4 meters). This DEM was used in determining the floodboundary for 11 flood stages at 0.5-ft intervals from 100.0 to104.0 ft (NGVD 29) and 1-ft intervals from 104.0 to 106.0 ft (NGVD 29) as referenced to the USGS lake gage 04295000, Richelieu River (Lake Champlain) at Rouses Point, N.Y. In addition, the May 2011 flood-inundation area for elevation103.20 ft (NGVD 29) (102.77 ft, North American Vertical Datum [NAVD] 88) was determined from this DEM. The May 2011 flood is the highest recorded lake water level (stage)at the Rouses Point, N.Y., lake gage. Flood stages greater than 101.5 ft (NGVD 29) exceed the “major flood stage”as defined by the NationalWeather Service for USGS lake gage 04295000.The availability of these maps, along with Internet information regarding current stage from the USGS lake gage and forecasted high-flow stages from the NationalWeather Service, will provide emergency management personnel and residents with information that is critical for flood responseactivities such as evacuations and road closures, as well as for post-flood recovery eforts.

Real-Time Application of Multi-Satellite Precipitation Analysis for Floods and Landslides

NASA Technical Reports Server (NTRS)

Adler, Robert; Hong, Yang; Huffman, George

2007-01-01

Satellite data acquired and processed in real time now have the potential to provide the spacetime information on rainfall needed to monitor flood and landslide events around the world. This can be achieved by integrating the satellite-derived forcing data with hydrological models and landslide algorithms. Progress in using the TRMM Multi-satellite Precipitation Analysis (TMPA) as input to flood and landslide forecasts is outlined, with a focus on understanding limitations of the rainfall data and impacts of those limitations on flood/landslide analyses. Case studies of both successes and failures will be shown, as well as comparison with ground comparison data sets-- both in terms of rainfall and in terms of flood/landslide events. In addition to potential uses in real-time, the nearly ten years of TMPA data allow retrospective running of the models to examine variations in extreme events. The flood determination algorithm consists of four major components: 1) multi-satellite precipitation estimation; 2) characterization of land surface including digital elevation from NASA SRTM (Shuttle Radar Terrain Mission), topography-derived hydrologic parameters such as flow direction, flow accumulation, basin, and river network etc.; 3) a hydrological model to infiltrate rainfall and route overland runoff; and 4) an implementation interface to relay the input data to the models and display the flood inundation results to potential users and decision-makers, In terms of landslides, the satellite rainfall information is combined with a global landslide susceptibility map, derived from a combination of global surface characteristics (digital elevation topography, slope, soil types, soil texture, and land cover classification etc.) using a weighted linear combination approach. In those areas identified as "susceptible" (based on the surface characteristics), landslides are forecast where and when a rainfall intensity/duration threshold is exceeded. Results are described indicating general agreement with landslide occurrences.

Incidence of and risk factors for musculoskeletal symptoms in the neck and low-back during severe flooding in Bangkok in 2011.

PubMed

Sihawong, Rattaporn; Janwantanakul, Prawit; Pensri, Praneet

2012-07-01

To examine whether the incidences of neck and low-back symptoms were elevated during the severe floods that occurred in Bangkok, Thailand in 2011, and to explore flood-related risk factors for neck and low-back symptoms. Prospective cohort design. Severe flooding occurred in Bangkok and surrounding neighbourhoods between October and December, 2011. After the flood had subsided (January 2012), 377 healthy office workers, who were already taking part in a study on musculoskeletal symptoms, were asked about their contact with floodwater. Data were gathered from subjects, who had reported no neck and low-back symptoms at the end of September 2011 and who were affected by the flood. Two regression models for the outcomes of 3-month incidence of neck and low-back symptoms, respectively, were performed. Eighty-two percent of the subjects were affected by the flood. No flood-related factor was found to associate significantly with either neck or low-back symptoms. However, neck symptoms may be associated with commuting frequently through flooded areas, and low-back symptoms may be associated with the subjects' homes or workplaces being flooded. These findings indicate that more attention needs to be paid to the problem of musculoskeletal symptoms during flooding in urban areas, and that preventive measures are required.

Flood of June 17, 1990, in the Clear Creek Basin, east-central Iowa

USGS Publications Warehouse

Barnes, K.K.; Eash, D.A.

1994-01-01

A water-surface-elevation profile for the flood of June 17, 1990, in the Clear Creek Basin, east-central Iowa, is given in this report. The maximum flood-peak discharge of 10,200 cubic feet per second for the streamflow-gaging station on Clear Creek near Coralville, Iowa (station number 05454300), occurred on June 17, 1990. This discharge was approximately equal to the 80-year recurrence-interval discharge. A flood history describes rainfall conditions for floods that occurred during 1982, 1990, and 1993.

Observed and forecast flood-inundation mapping application-A pilot study of an eleven-mile reach of the White River, Indianapolis, Indiana

USGS Publications Warehouse

Kim, Moon H.; Morlock, Scott E.; Arihood, Leslie D.; Kiesler, James L.

2011-01-01

Near-real-time and forecast flood-inundation mapping products resulted from a pilot study for an 11-mile reach of the White River in Indianapolis. The study was done by the U.S. Geological Survey (USGS), Indiana Silver Jackets hazard mitigation taskforce members, the National Weather Service (NWS), the Polis Center, and Indiana University, in cooperation with the City of Indianapolis, the Indianapolis Museum of Art, the Indiana Department of Homeland Security, and the Indiana Department of Natural Resources, Division of Water. The pilot project showed that it is technically feasible to create a flood-inundation map library by means of a two-dimensional hydraulic model, use a map from the library to quickly complete a moderately detailed local flood-loss estimate, and automatically run the hydraulic model during a flood event to provide the maps and flood-damage information through a Web graphical user interface. A library of static digital flood-inundation maps was created by means of a calibrated two-dimensional hydraulic model. Estimated water-surface elevations were developed for a range of river stages referenced to a USGS streamgage and NWS flood forecast point colocated within the study reach. These maps were made available through the Internet in several formats, including geographic information system, Keyhole Markup Language, and Portable Document Format. A flood-loss estimate was completed for part of the study reach by using one of the flood-inundation maps from the static library. The Federal Emergency Management Agency natural disaster-loss estimation program HAZUS-MH, in conjunction with local building information, was used to complete a level 2 analysis of flood-loss estimation. A Service-Oriented Architecture-based dynamic flood-inundation application was developed and was designed to start automatically during a flood, obtain near real-time and forecast data (from the colocated USGS streamgage and NWS flood forecast point within the study reach), run the two-dimensional hydraulic model, and produce flood-inundation maps. The application used local building data and depth-damage curves to estimate flood losses based on the maps, and it served inundation maps and flood-loss estimates through a Web-based graphical user interface.

Mapping Infected Area after a Flash-Flooding Storm Using Multi Criteria Analysis and Spectral Indices

NASA Astrophysics Data System (ADS)

Al-Akad, S.; Akensous, Y.; Hakdaoui, M.

2017-11-01

This research article is summarize the applications of remote sensing and GIS to study the urban floods risk in Al Mukalla. Satellite acquisition of a flood event on October 2015 in Al Mukalla (Yemen) by using flood risk mapping techniques illustrate the potential risk present in this city. Satellite images (The Landsat and DEM images data were atmospherically corrected, radiometric corrected, and geometric and topographic distortions rectified.) are used for flood risk mapping to afford a hazard (vulnerability) map. This map is provided by applying image-processing techniques and using geographic information system (GIS) environment also the application of NDVI, NDWI index, and a method to estimate the flood-hazard areas. Four factors were considered in order to estimate the spatial distribution of the hazardous areas: flow accumulation, slope, land use, geology and elevation. The multi-criteria analysis, allowing to deal with vulnerability to flooding, as well as mapping areas at the risk of flooding of the city Al Mukalla. The main object of this research is to provide a simple and rapid method to reduce and manage the risks caused by flood in Yemen by take as example the city of Al Mukalla.

Exploring Droughts and Floods and Their Association with Cholera Outbreaks in Sub-Saharan Africa: A Register-Based Ecological Study from 1990 to 2010

PubMed Central

Rieckmann, Andreas; Tamason, Charlotte C.; Gurley, Emily S.; Rod, Naja Hulvej; Jensen, Peter Kjær Mackie

2018-01-01

Abstract. Cholera outbreaks in Africa have been attributed to both droughts and floods, but whether the risk of a cholera outbreak is elevated during droughts is unknown. We estimated the risk of cholera outbreaks during droughts and floods compared with drought- and flood-free periods in 40 sub-Saharan African countries during 1990–2010 based on data from Emergency Events Database: the Office of Foreign Disaster Assistance /Centre for Research on the Epidemiology of Disasters International Disaster Database (www.emdat.be). A cholera outbreak was registered in one of every three droughts and one of every 15 floods. We observed an increased incidence rate of cholera outbreaks during drought periods (incidence rate ratio [IRR] = 4.3, 95% confidence interval [CI] = 2.9–7.2) and during flood periods (IRR = 144, 95% CI = 101–208) when compared with drought/flood-free periods. Floods are more strongly associated with cholera outbreaks, yet the prevalence of cholera outbreaks is higher during droughts because of droughts’ long durations. The results suggest that droughts in addition to floods call for increased cholera preparedness. PMID:29512484

Climate gentrification: from theory to empiricism in Miami-Dade County, Florida

NASA Astrophysics Data System (ADS)

Keenan, Jesse M.; Hill, Thomas; Gumber, Anurag

2018-05-01

This article provides a conceptual model for the pathways by which climate change could operate to impact geographies and property markets whose inferior or superior qualities for supporting the built environment are subject to a descriptive theory known as ‘Climate Gentrification.’ The article utilizes Miami-Dade County, Florida (MDC) as a case study to explore the market mechanisms that speak to the operations and processes inherent in the theory. This article tests the hypothesis that the rate of price appreciation of single-family properties in MDC is positively related to and correlated with incremental measures of higher elevation (the ‘Elevation Hypothesis’). As a reflection of an increase in observed nuisance flooding and relative SLR, the second hypothesis is that the rates of price appreciation in lowest the elevation cohorts have not kept up with the rates of appreciation of higher elevation cohorts since approximately 2000 (the ‘Nuisance Hypothesis’). The findings support a validation of both hypotheses and suggest the potential existence of consumer preferences that are based, in part, on perceptions of flood risk and/or observations of flooding. These preferences and perceptions are anticipated to be amplified by climate change in a manner that reinforces the proposition that climate change impacts will affect the marketability and valuation of property with varying degrees of environmental exposure and resilience functionality. Uncovering these empirical relationships is a critical first step for understanding the occurrence and parameters of Climate Gentrification.

Evaluation of vector coastline features extracted from 'structure from motion'-derived elevation data

USGS Publications Warehouse

Kinsman, Nicole; Gibbs, Ann E.; Nolan, Matt

2015-01-01

For extensive and remote coastlines, the absence of high-quality elevation models—for example, those produced with lidar—leaves some coastal populations lacking one of the essential elements for mapping shoreline positions or flood extents. Here, we compare seven different elevation products in a lowlying area in western Alaska to establish their appropriateness for coastal mapping applications that require the delineation of elevation-based vectors. We further investigate the effective use of a Structure from Motion (SfM)-derived surface model (vertical RMSE<20 cm) by generating a tidal datum-based shoreline and an inundation extent map for a 2011 flood event. Our results suggest that SfM-derived elevation products can yield elevation-based vector features that have horizontal positional uncertainties comparable to those derived from other techniques. We also provide a rule-of-thumb equation to aid in the selection of minimum elevation model specifications based on terrain slope, vertical uncertainties, and desired horizontal accuracy.

76 FR 58436 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-21

.... Approximately 105 feet None [caret]500 upstream of Haihai Street. Shallow Flooding Approximately 2.8 miles None 2 Hawaii County. northeast of the intersection of Ka'Ulu Street and 'Ahinahina Place. Shallow... and Naupaka Kai Place. [[Page 58438

77 FR 59767 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-01

... are in accordance with the National Flood Insurance Act of 1968, 42 U.S.C. 4001 et seq., and with 44.... Commissioners, 7375 Powell Road, Wildwood, FL 34785. New Mexico: Bernalillo (FEMA City of Albuquerque October 4...

Using Levee Setbacks to Increase Floodplain Connectivity and Reduce Flood Risk

NASA Astrophysics Data System (ADS)

Dahl, T. A.; Echevarria-Doyle, W.

2017-12-01

Levees typically constrain flood flows to within the main channel, isolating the river from its natural floodplain. Levees limit the areal and temporal extents of flooding, but can increase flood peaks, alter ecosystems, and cause scour. In order to mitigate these effects, some groups have begun moving portions of levees further away from the main channel, creating setback levees. Here we describe a series of levee setback scenarios for a hypothetical river that were modeled with the unsteady, 2D-hydraulic model AdH. In our scenarios, the water surface elevations were reduced both at the location of the levee setback and for some distance upstream. The models also show that the floodplain roughness can have a greater effect on the reduction in water surface elevation than the size of the levee setback. Groups planning levee setbacks can use these results to help guide their designs.

Tsunami vs Infragravity Surge: Statistics and Physical Character of Extreme Runup

NASA Astrophysics Data System (ADS)

Lynett, P. J.; Montoya, L. H.

2017-12-01

Motivated by recent observations of energetic and impulsive infragravity (IG) flooding events - also known as sneaker waves - we will present recent work on the relative probabilities and dynamics of extreme flooding events from tsunamis and long period wind wave events. The discussion will be founded on videos and records of coastal flooding by both recent tsunamis and IG, such as those in the Philippines during Typhoon Haiyan. From these observations, it is evident that IG surges may approach the coast as breaking bores with periods of minutes; a very tsunami-like character. Numerical simulations will be used to estimate flow elevations and speeds from potential IG surges, and these will be compared with similar values from tsunamis, over a range of different beach profiles. We will examine the relative rareness of each type of flooding event, which for large values of IG runup is a particularly challenging topic. For example, for a given runup elevation or flooding speed, the related tsunami return period may be longer than that associated with IG, implying that deposit information associated with such elevations or speeds are more likely to be caused by IG. Our purpose is to provide a statistical and physical discriminant between tsunami and IG, such that in areas exposed to both, a proper interpretation of overland transport, deposition, and damage is possible.

Anthropogenic Warming Impacts on Today's Sierra Nevada Snowpack and Flood Severity

NASA Astrophysics Data System (ADS)

Huang, X.; Hall, A. D.; Berg, N.

2017-12-01

Focusing on this recent extreme wet year over California, this study investigates the warming impacts on the snowpack and the flood severity over the Sierra Nevada (SN), where the majority of the precipitation occurs during the winter season and early spring. One of our goals is to quantify anthropogenic warming impacts on the snow water equivalent (SWE) including recent historical warming and prescribed future projected warming scenarios; This work also explores to what extent flooding risk has increased under those warming cases. With a good representation of the historical precipitation and snowpack over the Sierra Nevada from the historical reference run at 9km (using WRF), the results from the offline Noah-MP simulations with perturbed near-surface temperatures reveal magnificent impacts of warming to the loss of the average snowpack. The reduction of the SWE under warming mainly results from the decreased rain-to-snow conversion with a weaker effect from increased snowmelt. Compared to the natural case, the past industrial warming decreased the maximum SWE by about one-fifth averaged over the study area. Future continuing warming can result in around one-third reduction of current maximum SWE under RCP4.5 emissions scenario, and the loss can reach to two-thirds under RCP8.5 as a "business-as-usual" condition. The impact of past warming is particularly outstanding over the North SN region where precipitation dominates and over the middle elevation regions where the snow mainly distributes. In the future, the warming impact on SWE progresses to higher regions, and so to the south and east. Under the business-as-usual scenario, the projected mid-elevation snowpack almost disappears by April 1st with even high-elevation snow reduced by about half. Along with the loss of the snowpack, as the temperature warms, floods can also intensify with increased early season runoff especially under heavy-rainy days caused by the weakened rain-to-snow processes and strengthened snow-melt mainly over the mid-elevation region. Under continuing warming and predicted intensified precipitation extremes in the coming century, the severity of floods can become much more disastrous and potentially shift from the north (where the Oroville Dam spillway emergency occurred this February) to the central and south SN regions.

Floods at Mount Clemens, Michigan

USGS Publications Warehouse

Wiitala, S.W.; Ash, Arlington D.

1962-01-01

The approximate areas inundated during the flood of April 5-6, 1947, by Clinton River, North Branch and Middle Branch of Clinton River, and Harrington Drain, in Clinton Township, Macomb County, Mich., are shown on a topographic map base to record the flood hazard in graphical form. The flood of April 1947 is the highest known since 1934 and probably since 1902. Greater floods are possible, but no attempt was made to define their probable overflow limits.The Clinton River Cut-Off Canal, a flood-relief channel which diverts flow directly into Lake St. Clair from a point about 1500 feet downstream from Gratiot Avenue (about 9 miles upstream from the mouth) has been in operation since October 1951. The approximate limits of overflow that would results from a flood equivalent in discharge to that of April 1947, and occurring with the Cut-Off Canal in operation, are also shown. Although the Cut-Off Canal may reduce the frequency and depth of flooding it will not necessarily eliminate future flooding in the area. Improvements and additions to the drainage systems in the basin, expanding urbanization, new highways, and other cultural changes may influence the inundation pattern of future floods.The preparation of this flood inundation map was financed through a cooperative agreement between Clinton Township, Macomb County, Mich., and the U.S. Geological Survey.Backwater curves used to define the profile for a hypothetical flood on the Clinton River downstream from Moravian Drive, equivalent in discharge to the 1947 flood, but occurring with the present Cut-Off Canal in operation; flood stage established at the gaging station on Clinton River at Mount Clemens; and supplementary floodmark elevations were furnished by the Corps of Engineers.Bench-mark elevations and field survey data, used in the analysis of floods on Harrington Drain, were furnished by the Macomb County Drain Commission.

Development of flood-inundation maps for the West Branch Susquehanna River near the Borough of Jersey Shore, Lycoming County, Pennsylvania

USGS Publications Warehouse

Roland, Mark A.; Hoffman, Scott A.

2011-01-01

Streamflow data, water-surface-elevation profiles derived from a Hydrologic Engineering Center River Analysis System hydraulic model, and geographical information system digital elevation models were used to develop a set of 18 flood-inundation maps for an approximately 5-mile reach of the West Branch Susquehanna River near the Borough of Jersey Shore, Pa. The inundation maps were created by the U.S. Geological Survey in cooperation with the Susquehanna River Basin Commission and Lycoming County as part of an ongoing effort by the National Oceanic and Atmospheric Administration's National Weather Service to focus on continued improvements to the flood forecasting and warning abilities in the Susquehanna River Basin and to modernize flood-forecasting methodologies. The maps, ranging from 23.0 to 40.0 feet in 1-foot increments, correspond to river stage at the U.S. Geological Survey streamgage 01549760 at Jersey Shore. The electronic files used to develop the maps were provided to the National Weather Service for incorporation into their Advanced Hydrologic Prediction Service website. The maps are displayed on this website, which serves as a web-based floodwarning system, and can be used to identify areas of predicted flood inundation associated with forecasted flood-peak stages. During times of flooding or predicted flooding, these maps can be used by emergency managers and the public to take proactive steps to protect life and reduce property damage caused by floods.

Diversity and above-ground biomass patterns of vascular flora induced by flooding in the drawdown area of China's Three Gorges Reservoir.

PubMed

Wang, Qiang; Yuan, Xingzhong; Willison, J H Martin; Zhang, Yuewei; Liu, Hong

2014-01-01

Hydrological alternation can dramatically influence riparian environments and shape riparian vegetation zonation. However, it was difficult to predict the status in the drawdown area of the Three Gorges Reservoir (TGR), because the hydrological regime created by the dam involves both short periods of summer flooding and long-term winter impoundment for half a year. In order to examine the effects of hydrological alternation on plant diversity and biomass in the drawdown area of TGR, twelve sites distributed along the length of the drawdown area of TGR were chosen to explore the lateral pattern of plant diversity and above-ground biomass at the ends of growing seasons in 2009 and 2010. We recorded 175 vascular plant species in 2009 and 127 in 2010, indicating that a significant loss of vascular flora in the drawdown area of TGR resulted from the new hydrological regimes. Cynodon dactylon and Cyperus rotundus had high tolerance to short periods of summer flooding and long-term winter flooding. Almost half of the remnant species were annuals. Species richness, Shannon-Wiener Index and above-ground biomass of vegetation exhibited an increasing pattern along the elevation gradient, being greater at higher elevations subjected to lower submergence stress. Plant diversity, above-ground biomass and species distribution were significantly influenced by the duration of submergence relative to elevation in both summer and previous winter. Several million tonnes of vegetation would be accumulated on the drawdown area of TGR in every summer and some adverse environmental problems may be introduced when it was submerged in winter. We conclude that vascular flora biodiversity in the drawdown area of TGR has dramatically declined after the impoundment to full capacity. The new hydrological condition, characterized by long-term winter flooding and short periods of summer flooding, determined vegetation biodiversity and above-ground biomass patterns along the elevation gradient in the drawdown area.

Diversity and Above-Ground Biomass Patterns of Vascular Flora Induced by Flooding in the Drawdown Area of China's Three Gorges Reservoir

PubMed Central

Wang, Qiang; Yuan, Xingzhong; Willison, J.H.Martin; Zhang, Yuewei; Liu, Hong

2014-01-01

Hydrological alternation can dramatically influence riparian environments and shape riparian vegetation zonation. However, it was difficult to predict the status in the drawdown area of the Three Gorges Reservoir (TGR), because the hydrological regime created by the dam involves both short periods of summer flooding and long-term winter impoundment for half a year. In order to examine the effects of hydrological alternation on plant diversity and biomass in the drawdown area of TGR, twelve sites distributed along the length of the drawdown area of TGR were chosen to explore the lateral pattern of plant diversity and above-ground biomass at the ends of growing seasons in 2009 and 2010. We recorded 175 vascular plant species in 2009 and 127 in 2010, indicating that a significant loss of vascular flora in the drawdown area of TGR resulted from the new hydrological regimes. Cynodon dactylon and Cyperus rotundus had high tolerance to short periods of summer flooding and long-term winter flooding. Almost half of the remnant species were annuals. Species richness, Shannon-Wiener Index and above-ground biomass of vegetation exhibited an increasing pattern along the elevation gradient, being greater at higher elevations subjected to lower submergence stress. Plant diversity, above-ground biomass and species distribution were significantly influenced by the duration of submergence relative to elevation in both summer and previous winter. Several million tonnes of vegetation would be accumulated on the drawdown area of TGR in every summer and some adverse environmental problems may be introduced when it was submerged in winter. We conclude that vascular flora biodiversity in the drawdown area of TGR has dramatically declined after the impoundment to full capacity. The new hydrological condition, characterized by long-term winter flooding and short periods of summer flooding, determined vegetation biodiversity and above-ground biomass patterns along the elevation gradient in the drawdown area. PMID:24971514

Multi-scale Visualization of Remote Sensing and Topographic Data of the Amazon Rain Forest for Environmental Monitoring of the Petroleum Industry.

NASA Astrophysics Data System (ADS)

Fonseca, L.; Miranda, F. P.; Beisl, C. H.; Souza-Fonseca, J.

2002-12-01

PETROBRAS (the Brazilian national oil company) built a pipeline to transport crude oil from the Urucu River region to a terminal in the vicinities of Coari, a city located in the right margin of the Solimoes River. The oil is then shipped by tankers to another terminal in Manaus, capital city of the Amazonas state. At the city of Coari, changes in water level between dry and wet seasons reach up to 14 meters. This strong seasonal character of the Amazonian climate gives rise to four distinct scenarios in the annual hydrological cycle: low water, high water, receding water, and rising water. These scenarios constitute the main reference for the definition of oil spill response planning in the region, since flooded forests and flooded vegetation are the most sensitive fluvial environments to oil spills. This study focuses on improving information about oil spill environmental sensitivity in Western Amazon by using 3D visualization techniques to help the analysis and interpretation of remote sensing and digital topographic data, as follows: (a) 1995 low flood and 1996 high flood JERS-1 SAR mosaics, band LHH, 100m pixel; (b) 2000 low flood and 2001 high flood RADARSAT-1 W1 images, band CHH, 30m pixel; (c) 2002 high flood airborne SAR images from the SIVAM project (System for Surveillance of the Amazon), band LHH, 3m pixel and band XHH, 6m pixel; (d) GTOPO30 digital elevation model, 30' resolution; (e) Digital elevation model derived from topographic information acquired during seismic surveys, 25m resolution; (f) panoramic views obtained from low altitude helicopter flights. The methodology applied includes image processing, cartographic conversion and generation of value-added product using 3D visualization. A semivariogram textural classification was applied to the SAR images in order to identify areas of flooded forest and flooded vegetation. The digital elevation models were color shaded to highlight subtle topographic features. Both datasets were then converted to the same cartographic projection and inserted into the Fledermaus 3D visualization environment. 3D visualization proved to be an important aid in understanding the spatial distribution pattern of the environmentally sensitive vegetation cover. The dynamics of the hydrological cycle was depicted in a basin-wide scale, revealing new geomorphic information relevant to assess the environmental risk of oil spills. Results demonstrate that pipelines constitute an environmentally saver option for oil transportation in the region when compared to fluvial tanker routes.

Spatial patterns of water-dispersed seed deposition along stream riparian gradients

PubMed Central

Moinier, Sophie; van Gogh, Iris; Timmers, Robert; van Deelen, Joost J.; Verhoeven, Jos T. A.; Soons, Merel B.

2017-01-01

Riparian ecosystems along streams naturally harbour a high plant diversity with many increasingly endangered species. In our current heavily modified and fragmented catchments, many of these species are sensitive to dispersal limitation. Better understanding of riparian plant dispersal pathways is required to predict species (re-)colonization potential and improve success rates of stream and riparian zone conservation and restoration. Dispersal by water (hydrochory) is an important mechanism for longitudinal and lateral dispersal of riparian species. Crucially for recruitment potential, it also influences the elevation along the riparian hydrological gradient where seeds become deposited. Due to the complex interplay between abiotic and biotic factors, however, it remains unclear how exactly patterns in seed deposition are formed. We compared hydrochorous and non-hydrochorous seed deposition, and quantified patterns of seed deposition along the bare substrate of newly created stream riparian gradients. Water levels were monitored and seed deposition was measured with seed traps along the full range of riparian hydrological conditions (from permanently flooded to never flooded). Average seed numbers and species richness were significantly higher in flooded than in non-flooded seed traps (5.7 and 1.5 times higher, respectively). Community-weighted trait means indicated that typically water-dispersed seeds were more dominant in flooded than in non-flooded seed traps and gradually decreased in concentration from the channel to the upland. Moreover, highly buoyant seeds accumulated at the average water line, and clear elevational sorting of non-buoyant seeds occurred within the floodplain. These results establish a critical role of flooding in shaping patterns of seed deposition along the riparian gradient, delivering many seeds of typical riparian species to riparian zones and depositing them at species-specific elevations as influenced by seed traits, suggesting species-specific dispersal pathways. This shows that hydrochory likely has important consequences for riparian vegetation development and that flooding forms a key process for successful restoration. PMID:28957365

Ste. Genevieve, Missouri Feasibility Report (Flood Control Study for Historic Ste. Genevieve - 80061). Volume 2. Appendices.

DTIC Science & Technology

1984-06-01

A greater seismic risk may be posed by two other zones: the *-."Southern Illinois - Wabash Zone and the New Madrid Zone. Earthquake ground motions...A-3 S 0I The study area is located in the Ozark Random Source Zone. This *seismotectonic zone is a region of moderate seismicity ( earthquake activity...40 inches, so that the tops of the casings are now 57 inches above the 1973 flood height. The new well casings’ elevations are approximately 395 feet

Application of satellite radar altimetry for near-real time monitoring of floods

NASA Astrophysics Data System (ADS)

Lee, H.; Calmant, S.; Shum, C.; Kim, J.; Huang, Z.; Bettadpur, S. V.; Alsdorf, D. E.

2011-12-01

According to the 2004 UNESCO World Disasters Report, it is estimated that flooding affected 116 million people globally, causing about 7000 deaths and leading to $7.5 billion in losses. The report also indicates that flood is the most frequently occurring disaster type among all other natural disasters. Hence, timely monitoring of changing of river, wetland and lake/reservoir levels is important to support disaster monitoring and proper response. Yet, we have surprisingly poor knowledge of the spatial and temporal dynamics of surface water discharge and storage changes globally. Although satellite radar altimetry has been successfully used to observe water height changes over rivers, lakes, reservoirs, and wetlands, there have been few studies for near-real time monitoring of floods mainly due to its limited spatial and temporal sampling of surface water elevations. In this study, we monitor flood by examining its spatial and temporal origin of the flooding and its timely propagation using multiple altimeter-river intersections over the entire hydrologic basin. We apply our method to the Amazon 2009 flood event that caused the most severe flooding in more than two decades. We also compare our results with inundated areas estimated from ALOS PALSAR ScanSAR measurements and GRACE 15-day Quick-Look (QL) gravity field data product. Our developed method would potentially enhance the capability of satellite altimeter toward near-real time monitoring of floods and mitigating their hazards.

Flood-inundation maps for the Tippecanoe River at Winamac, Indiana

USGS Publications Warehouse

Menke, Chad D.; Bunch, Aubrey R.

2015-09-25

For this study, flood profiles were computed for the Tippecanoe River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Tippecanoe River streamgage, in combination with the current (2014) Federal Emergency Management Agency flood-insurance study for Pulaski County. The calibrated hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability (AEP) flood stage (flood with recurrence intervals within 100 years) has not been determined yet for this streamgage location. The rating has not been developed for the 1-percent AEP because the streamgage dates to only 2001. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 03331753, Tippecanoe River at Winamac, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

76 FR 1093 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-07

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Stephenson County.../Wisconsin +782 State boundary. Yellow Creek Approximately 400 feet +814 Unincorporated Areas of downstream... Sea Level, rounded to the nearest 0.1 meter. ADDRESSES City of Freeport Maps are available for...

76 FR 20606 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-13

... source(s) Location of referenced ground [caret] Communities affected elevation ** Elevation in meters (MSL) Effective Modified Sevier County, Utah, and Incorporated Areas Albinus Canyon Approximately 400... Creek Split Flow Approximately 400 feet None +5435 Town of Joseph. downstream of State Highway 118. At...

The Effects of the Saluda Dam on the Surface-Water and Ground-Water Hydrology of the Congaree National Park Flood Plain, South Carolina

USGS Publications Warehouse

Conrads, Paul; Feaster, Toby D.; Harrelson, Larry G.

2008-01-01

The Congaree National Park was established '... to preserve and protect for the education, inspiration, and enjoyment of present and future generations an outstanding example of a near-virgin, southern hardwood forest situated in the Congaree River flood plain in Richland County, South Carolina' (Public Law 94-545). The resource managers at Congaree National Park are concerned about the timing, frequency, magnitude, and duration of flood-plain inundation of the Congaree River. The dynamics of the Congaree River directly affect ground-water levels in the flood plain, and the delivery of sediments and nutrients is constrained by the duration, extent, and frequency of flooding from the Congaree River. The Congaree River is the southern boundary of the Congaree National Park and is formed by the convergence of the Saluda and Broad Rivers 24 river miles upstream from the park. The streamflow of the Saluda River has been regulated since 1929 by the operation of the Saluda Dam at Lake Murray. The U.S. Geological Survey, in cooperation with the National Park Service, Congaree National Park, studied the interaction between surface water in the Congaree River and ground water in the flood plain to determine the effect Saluda Dam operations have on water levels in the Congaree National Park flood plain. Analysis of peak flows showed the reduction in peak flows after the construction of Lake Murray was more a result of climate variability and the absence of large floods after 1930 than the operation of the Lake Murray dam. Dam operations reduced the recurrence interval of the 2-year to 100-year peak flows by 6.1 to 17.6 percent, respectively. Analysis of the daily gage height of the Congaree River showed that the dam has had the effect of lowering high gage heights (95th percentile) in the first half of the year (December to May) and raising low gage heights (5th percentile) in the second half of the year (June to November). The dam has also had the effect of increasing the 1-, 3-, 7-, 30-, and 90-day minimum gage heights by as much as 23.9 percent and decreasing the 1-, 3-, 7-, 30-, and 90-day maximum gage heights by as much as 7.2 percent. Analysis of the ground-water elevations in the Congaree National Park flood plain shows similar results as the gage-height analysis--the dam has had the effect of lowering high ground-water elevations and increasing low ground-water elevations. Overall, the operation of the dam has had a greater effect on the gage heights within the river banks than gage heights in the flood plain. This result may have a greater effect on the subsurface water levels of the surficial flood-plain aquifer than the frequency and magnitude of inundation of the flood plain.

LiDAR and IFSAR-Based Flood Inundation Model Estimates for Flood-Prone Areas of Afghanistan

NASA Astrophysics Data System (ADS)

Johnson, W. C.; Goldade, M. M.; Kastens, J.; Dobbs, K. E.; Macpherson, G. L.

2014-12-01

Extreme flood events are not unusual in semi-arid to hyper-arid regions of the world, and Afghanistan is no exception. Recent flashfloods and flashflood-induced landslides took nearly 100 lives and destroyed or damaged nearly 2000 homes in 12 villages within Guzargah-e-Nur district of Baghlan province in northeastern Afghanistan. With available satellite imagery, flood-water inundation estimation can be accomplished remotely, thereby providing a means to reduce the impact of such flood events by improving shared situational awareness during major flood events. Satellite orbital considerations, weather, cost, data licensing restrictions, and other issues can often complicate the acquisition of appropriately timed imagery. Given the need for tools to supplement imagery where not available, complement imagery when it is available, and bridge the gap between imagery based flood mapping and traditional hydrodynamic modeling approaches, we have developed a topographic floodplain model (FLDPLN), which has been used to identify and map river valley floodplains with elevation data ranging from 90-m SRTM to 1-m LiDAR. Floodplain "depth to flood" (DTF) databases generated by FLDPLN are completely seamless and modular. FLDPLN has been applied in Afghanistan to flood-prone areas along the northern and southern flanks of the Hindu Kush mountain range to generate a continuum of 1-m increment flood-event models up to 10 m in depth. Elevation data used in this application of FLDPLN included high-resolution, drone-acquired LiDAR (~1 m) and IFSAR (5 m; INTERMAP). Validation of the model has been accomplished using the best available satellite-derived flood inundation maps, such as those issued by Unitar's Operational Satellite Applications Programme (UNOSAT). Results provide a quantitative approach to evaluating the potential risk to urban/village infrastructure as well as to irrigation systems, agricultural fields and archaeological sites.

Pittsfield Local Flood Protection, West Branch and Southwest Branch, Housatonic River, Pittsfield, Massachusetts. Detailed Project Report for Water Resources Development.

DTIC Science & Technology

1980-10-01

a bakery , a gas station, and the Linden Street bridge were flooded during the March 1977 storm. Flooding also occurred on the Southwest Branch...and service station, one bakery , and five other commercial establishments. Most of these structures are not suited to being elevated above the design...of a shopping plaza and a fast-food franchise in the flood plain on West Housatonic Street (Route 20). The following three alternate plans of

The impact of sea-level rise on organic matter decay rates in Chesapeake Bay brackish tidal marshes

USGS Publications Warehouse

Kirwanm, M.L.; Langley, J.A.; Guntenspergen, Gleen R.; Megonigal, J.P.

2013-01-01

The balance between organic matter production and decay determines how fast coastal wetlands accumulate soil organic matter. Despite the importance of soil organic matter accumulation rates in influencing marsh elevation and resistance to sea-level rise, relatively little is known about how decomposition rates will respond to sea-level rise. Here, we estimate the sensitivity of decomposition to flooding by measuring rates of decay in 87 bags filled with milled sedge peat, including soil organic matter, roots and rhizomes. Experiments were located in field-based mesocosms along 3 mesohaline tributaries of the Chesapeake Bay. Mesocosm elevations were manipulated to influence the duration of tidal inundation. Although we found no significant influence of inundation on decay rate when bags from all study sites were analyzed together, decay rates at two of the sites increased with greater flooding. These findings suggest that flooding may enhance organic matter decay rates even in water-logged soils, but that the overall influence of flooding is minor. Our experiments suggest that sea-level rise will not accelerate rates of peat accumulation by slowing the rate of soil organic matter decay. Consequently, marshes will require enhanced organic matter productivity or mineral sediment deposition to survive accelerating sea-level rise.

The impact of sea-level rise on organic matter decay rates in Chesapeake Bay brackish tidal marshes

NASA Astrophysics Data System (ADS)

Kirwan, M. L.; Langley, J. A.; Guntenspergen, G. R.; Megonigal, J. P.

2013-03-01

The balance between organic matter production and decay determines how fast coastal wetlands accumulate soil organic matter. Despite the importance of soil organic matter accumulation rates in influencing marsh elevation and resistance to sea-level rise, relatively little is known about how decomposition rates will respond to sea-level rise. Here, we estimate the sensitivity of decomposition to flooding by measuring rates of decay in 87 bags filled with milled sedge peat, including soil organic matter, roots and rhizomes. Experiments were located in field-based mesocosms along 3 mesohaline tributaries of the Chesapeake Bay. Mesocosm elevations were manipulated to influence the duration of tidal inundation. Although we found no significant influence of inundation on decay rate when bags from all study sites were analyzed together, decay rates at two of the sites increased with greater flooding. These findings suggest that flooding may enhance organic matter decay rates even in water-logged soils, but that the overall influence of flooding is minor. Our experiments suggest that sea-level rise will not accelerate rates of peat accumulation by slowing the rate of soil organic matter decay. Consequently, marshes will require enhanced organic matter productivity or mineral sediment deposition to survive accelerating sea-level rise.

The impact of sea-level rise on organic matter decay rates in Chesapeake Bay brackish tidal marshes

NASA Astrophysics Data System (ADS)

Kirwan, M. L.; Langley, J. A.; Guntenspergen, G. R.; Megonigal, J. P.

2012-10-01

The balance between organic matter production and decay determines how fast coastal wetlands accumulate soil organic matter. Despite the importance of soil organic matter accumulation rates in influencing marsh elevation and resistance to sea-level rise, relatively little is known about how decomposition rates will respond to sea-level rise. Here, we estimate the sensitivity of decomposition to flooding by measuring rates of decay in 87 bags filled with milled sedge peat, including soil organic matter, roots and rhizomes. Experiments were located in field-based mesocosms along 3 mesohaline tributaries of the Chesapeake Bay. Mesocosm elevations were manipulated to influence the duration of tidal inundation. Although we found no significant influence of inundation on decay rate when bags from all study sites were analyzed together, decay rates at two of the sites increased with greater flooding. These findings suggest that flooding may enhance organic matter decay rates even in water-logged soils, but that the overall influence of flooding is minor. Our experiments suggest that sea-level rise will not accelerate rates of peat accumulation by slowing the rate of soil organic matter decay. Consequently, marshes will require enhanced organic matter productivity or mineral sediment deposition to survive accelerating sea-level rise.

Application of High-resolution Aerial LiDAR Data in Calibration of a Two-dimensional Urban Flood Simulation

NASA Astrophysics Data System (ADS)

Piotrowski, J.; Goska, R.; Chen, B.; Krajewski, W. F.; Young, N.; Weber, L.

2009-12-01

In June 2008, the state of Iowa experienced an unprecedented flood event which resulted in an economic loss of approximately $2.88 billion. Flooding in the Iowa River corridor, which exceeded the previous flood of record by 3 feet, devastated several communities, including Coralville and Iowa City, home to the University of Iowa. Recognizing an opportunity to capture a unique dataset detailing the impacts of the historic flood, the investigators contacted the National Center for Airborne Laser Mapping (NCALM), which performed an aerial Light Detection and Ranging (LiDAR) survey along the Iowa River. The survey, conducted immediately following the flood peak, provided coverage of a 60-mile reach. The goal of the present research is to develop a process by which flood extents and water surface elevations can be accurately extracted from the LiDAR data set and to evaluate the benefit of such data in calibrating one- and two-dimensional hydraulic models. Whereas data typically available for model calibration include sparsely distributed point observations and high water marks, the LiDAR data used in the present study provide broad-scale, detailed, and continuous information describing the spatial extent and depth of flooding. Initial efforts were focused on a 10-mile, primarily urban reach of the Iowa River extending from Coralville Reservoir, a United States Army Corps of Engineers flood control project, downstream through the Coralville and Iowa City. Spatial extent and depth of flooding were estimated from the LiDAR data. At a given cross-sectional location, river channel and floodplain measurements were compared. When differences between floodplain and river channel measurements were less than a standard deviation of the vertical uncertainty in the LiDAR survey, floodplain measurements were classified as flooded. A flood water surface DEM was created using measurements classified as flooded. A two-dimensional, depth-averaged numerical model of a 10-mile reach of the Iowa River corridor was developed using the United States Bureau of Reclamation SRH-2D hydraulic modeling software. The numerical model uses an unstructured numerical mesh and variable surface roughness, assigned according to observed land use and cover. The numerical model was calibrated using inundation extents and water surface elevations derived from the LiDAR data. It was also calibrated using high water marks and land survey data collected daily during the 2008 flood. The investigators compared the two calibrations to evaluate the benefit of high-resolution LiDAR data in improving the accuracy of a two-dimensional urban flood simulation.

Beyond the gorge: Palaeoflood reconstruction from slackwater deposits in a range of physiographic settings in subtropical Australia

NASA Astrophysics Data System (ADS)

Lam, Daryl; Croke, Jacky; Thompson, Chris; Sharma, Ashneel

2017-09-01

The application of palaeoflood hydrology in Australia has been limited since its initial introduction > 30 years ago. This study adopts a regional, field-based approach to sampling slackwater deposits in a subtropical setting in southeast Queensland beyond the traditional arid setting. We explore the potential and challenges of using sites outside the traditional physiographical setting of bedrock gorges. Over 30 flood units were identified across different physiographical settings using a range of criteria. Evidence of charcoal-rich layers and palaeosol development assisted in the identification and separation of distinct flood units. The OSL-dated flood units are relatively young with two-thirds of the samples being < 1000 years old. The elevation of all flood units have resulted in estimated minimum discharges greater than the 1% annual exceedance probability. Although these are in the same order of gauged flood magnitudes, > 80% of them classified as 'extreme event'. This study opens up the renewed possibility of applying palaeoflood hydrology to more populated parts of Australia where the need for improved estimation of flood frequency and magnitude is now urgent in light of several extreme flood events. Preliminary contributions to improve the understanding between high magnitude floods and regional climatic drivers are also discussed. Recognised regional extreme floods generally coincide with La Niña and negative IPO phases, while tropical cyclones appear to be a key weather system in generating such large floods.

76 FR 54415 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-01

... following flooding sources: Bear Creek (backwater effects from Cumberland River), Big Renox Creek (backwater effects from Cumberland River), Big Whetstone Creek (backwater effects from Cumberland River), Big Willis... River), Big Renox Creek (backwater effects from Cumberland River), Big Whetstone Creek (backwater...

NOAA predicts moderate flood potential in Midwest, elevated risk of ice

Science.gov Websites

individuals to become weather-ready by ensuring you have real-time access to flood warnings via mobile devices and marine resources. Join us on Facebook, Twitter and our other social media channels. NOAA Mobile

44 CFR 67.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 44 Emergency Management and Assistance 1 2012-10-01 2011-10-01 true Definitions. 67.2 Section 67.2 Emergency Management and Assistance FEDERAL EMERGENCY MANAGEMENT AGENCY, DEPARTMENT OF HOMELAND SECURITY INSURANCE AND HAZARD MITIGATION National Flood Insurance Program APPEALS FROM PROPOSED FLOOD ELEVATION...

Flood profiles for lower Brooker Creek, west-central Florida

USGS Publications Warehouse

Murphy, W.R.

1978-01-01

Flood heights are computed for a range of recurrence intervals for a 12.6 mile reach of Brooker Creek, beginning at the mouth at Lake Tarpon. A Geological Survey step-backwater computer program, E431, was used in these analyses using: (1) Stream and valley cross-section geometry and roughness data; (2) Recurrence interval flood-peak discharges; (3) Recurrence interval starting elevations; (4) Gaging station stage-discharge relations. Flood heights may be plotted versus distance above stream mouth and connected to construct flood profiles. They may also be used to indicate areas of inundation on detailed topographic maps.

Upper and Lower Hamburg Bend 2011 Flood Evaluation on the Missouri River near Hamburg, Iowa

DTIC Science & Technology

2017-01-01

flood event. The evaluation required numerical hydrodynamic modeling of a pre-2011 flood condition of the entire floodplain and main channel with...59 Figure 50. Task 6.3 elevation differences for the degraded main channel and chutes...Table 2. Model computed flow splits between the chutes and the main channel . ............................. 76 ERDC/CHL TR-17-1 vii Preface This

Flood of May 5 and 6, 1981, Mobile, Alabama

USGS Publications Warehouse

Ming, C.O.; Nelson, G.H.

1981-01-01

Heavy and intense rainfall in the late evening and early morning hours, May 5 and 6, 1981, caused widespread flooding along streams and low-lying areas in the port city of Mobile, Ala. More than 12 inches of rain fell between 6 p.m. May 5, and 3 a.m. May 6. Damage caused by flooding was estimated by the Mobile Department of Public Works to be millions of dollars. Maximum water surface elevations on streams in the area were 2 to 3 feet higher than those that occurred during a similar flood in April 1980. The approximate extent of flooding delineated on maps using flood profiles obtained by field surveys will provide a basis for formulating effective flood plain zoning that could minimize existing and future flood problems. (USGS)

76 FR 50920 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-17

... Depth in feet Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified... above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES Unincorporated Areas... Unincorporated Areas of downstream of Main Butler County. Street. Approximately 400 feet + 958 upstream of Main...

76 FR 39305 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-06

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Franklin County... Level, rounded to the nearest 0.1 meter. ADDRESSES Unincorporated Areas of Franklin County Maps are....1 meter. ADDRESSES City of Spring Valley Maps are available for inspection at City Hall, 215 North...

75 FR 59989 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-29

... referenced Depth in feet Communities affected elevation above ground [caret] Elevation in meters (MSL... meter. ADDRESSES City of Lufkin Maps are available for inspection at 300 East Shepherd Avenue, Lufkin... Creek Approximately 400 feet +592 City of San Antonio. downstream of Probandt Street. Approximately 400...

76 FR 62329 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-07

...] Communities affected elevation * * Elevation in meters (MSL) Effective Modified Anne Arundel County, Maryland... + 8 + 10 Unincorporated Areas of Crain Highway. Anne Arundel County. Approximately 400 feet None + 105... American Vertical Datum. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. * * BFEs to be changed...

78 FR 36099 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-17

... Communities affected elevation above ground [caret]Elevation in meters (MSL) Modified Maricopa County, Arizona... Unincorporated Areas of upstream of the Camp Maricopa County. Creek Tributary A confluence. Approximately 400... miles +2857 upstream of the Camp Creek Tributary C confluence. Camp Creek Tributary C2 Approximately 400...

76 FR 39800 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-07

... referenced ground [caret] Communities affected elevation ** Elevation in meters (MSL) Effective Modified.... Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. [[Page 39802... Unincorporated Areas Logsboro Road. of Edgecombe County. Approximately 400 feet +91 +90 downstream of the...

76 FR 9668 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-22

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Logan County, Arkansas... Level, rounded to the nearest 0.1 meter. ADDRESSES City of Booneville Maps are available for inspection..., rounded to the nearest 0.1 meter. ADDRESSES Pinoleville Indian Reservation Maps are available for...

76 FR 68107 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-03

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Lee County, Alabama... Areas of Saugahatchee Creek. Lee County. Approximately 1.9 miles +537 upstream of the confluence with..., Saugahatchee Creek. Unincorporated Areas of Lee County. Approximately 640 feet +693 upstream of Gatewood Drive...

Flood regime and leaf fall determine soil inorganic nitrogen dynamics in semiarid riparian forests.

PubMed

Shah, J J Follstad; Dahm, C N

2008-04-01

Flow regulation has reduced the exchange of water, energy, and materials between rivers and floodplains, caused declines in native plant populations, and advanced the spread of nonnative plants. Naturalized flow regimes are regarded as a means to restore degraded riparian areas. We examined the effects of flood regime (short [SIFI] vs. long [LIFI] inter-flood interval) on plant community and soil inorganic nitrogen (N) dynamics in riparian forests dominated by native Populus deltoides var. wislizenii Eckenwalder (Rio Grande cottonwood) and nonnative Tamarix chinensis Lour. (salt cedar) along the regulated middle Rio Grande of New Mexico. The frequency of inundation (every 2-3 years) at SIFI sites better reflected inundation patterns prior to the closure of an upstream dam relative to the frequency of inundation at LIFI sites (> or =10 years). Riparian inundation at SIFI sites varied from 7 to 45 days during the study period (April 2001-July 2004). SIFI vs. LIFI sites had higher soil moisture but greater groundwater table elevation fluctuation in response to flooding and drought. Rates of net N mineralization were consistently higher at LIFI vs. SIFI sites, and soil inorganic N concentrations were greatest at sites with elevated leaf-litter production. Sites with stable depth to ground water (approximately 1.5 m) supported the greatest leaf-litter production. Reduced leaf production at P. deltoides SIFI sites was attributed to drought-induced recession of ground water and prolonged inundation. We recommend that natural resource managers and restoration practitioners (1) utilize naturalized flows that help maintain riparian groundwater elevations between 1 and 3 m in reaches with mature P. deltoides or where P. deltoides revegetation is desired, (2) identify areas that naturally undergo long periods of inundation and consider restoring these areas to seasonal wetlands, and (3) use native xeric-adapted riparian plants to revegetate LIFI and SIFI sites where groundwater elevations commonly drop below 3 m.

Flooding of Ganymede's bright terrains by low-viscosity water-ice lavas.

PubMed

Schenk, P M; McKinnon, W B; Gwynn, D; Moore, J M

2001-03-01

Large regions of the jovian moon Ganymede have been resurfaced, but the means has been unclear. Suggestions have ranged from volcanic eruptions of liquid water or solid ice to tectonic deformation, but definitive high-resolution morphological evidence has been lacking. Here we report digital elevation models of parts of the surface of Ganymede, derived from stereo pairs combining data from the Voyager and Galileo spacecraft, which reveal bright, smooth terrains that lie at roughly constant elevations 100 to 1,000 metres below the surrounding rougher terrains. These topographic data, together with new images that show fine-scale embayment and burial of older features, indicate that the smooth terrains were formed by flooding of shallow structural troughs by low-viscosity water-ice lavas. The oldest and most deformed areas (the 'reticulate' terrains) in general have the highest relative elevations, whereas units of the most common resurfaced type--the grooved terrain--lie at elevations between those of the smooth and reticulate terrains. Bright terrain, which accounts for some two-thirds of the surface, probably results from a continuum of processes, including crustal rifting, shallow flooding and groove formation. Volcanism plays an integral role in these processes, and is consistent with partial melting of Ganymede's interior.

Hydrological disposition of flash flood and debris flows events in an Alpine watershed in Austria

NASA Astrophysics Data System (ADS)

Prenner, David; Kaitna, Roland; Mostbauer, Karin; Hrachowitz, Markus

2017-04-01

Debris flows and flash floods including intensive bedload transport represent severe hazards in the Alpine environment of Austria. For neither of these processes, explicit rainfall thresholds - even for specific regions - are available. This may be due to insufficient data on the temporal and spatial variation of precipitation, but probably also due to variations of the geomorphic and hydrological disposition of a watershed to produce such processes in the course of a rainfall event. In this contribution we investigate the importance of the hydrological system state for triggering debris flows and flash floods in the Ill/Suggadin watershed (500 km2), Austria, by analyzing the effects of dynamics in system state variables such as soil moisture, snow pack, or ground water level. The analysis is based on a semi-distributed conceptual rainfall-runoff model, spatially discretizing the watershed according to the available precipitation observations, elevation, topographic considerations and land cover. Input data are available from six weather stations on a daily basis ranging back to 1947. A Thiessen polygon decomposition results in six individual precipitation zones with a maximum area of about 130 km2. Elevation specific behavior of the quantities temperature and precipitation is covered through an elevation-resolved computation every 200 m. Spatial heterogeneity is considered by distinct hydrological response units for bare rock, forest, grassland, and riparian zone. To reduce numerical smearing on the hydrological results, the Implicit Euler scheme was used to discretize the balance equations. For model calibration we utilized runoff hydrographs, snow cover data as well as prior parameter and process constraints. The obtained hydrological output variables are linked to documented observed flash flood and debris flow events by means of a multivariate logistic regression. We present a summary about the daily hydrological disposition of experiencing a flash flood or debris flow event in each precipitation zone of the Ill/Suggadin region over almost 65 years. Furthermore, we will provide an interpretation of the occurred hydrological trigger patterns and show a frequency ranking. The outcomes of this study shall lead to an improved forecasting and differentiation of trigger conditions leading to debris flows and flash floods.

22. Top 30/5. Plan of superstructure elevations. Wyoming Valley ...

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

22. Top 30/5. Plan of superstructure elevations. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

Maps Showing Inundation Depths, Ice-Rafted Erratics, and Sedimentary Facies of Late Pleistocene Missoula Floods in the Willamette Valley, Oregon

USGS Publications Warehouse

Minervini, J.M.; O'Connor, J. E.; Wells, R.E.

2003-01-01

Glacial Lake Missoula, impounded by the Purcell Trench lobe of the late Pleistocene Cordilleran Icesheet, repeatedly breached its ice dam, sending floods as large as 2,500 cubic kilometers racing across the Channeled Scabland and down the Columbia River valley to the Pacific Ocean. Peak discharges for some floods exceeded 20 million cubic meters per second. At valley constrictions along the flood route, floodwaters temporarily ponded behind each narrow zone. One such constriction at Kalama Gap-northwest of Portland-backed water 120-150 meters high in the Portland basin, and backflooded 200 km south into Willamette Valley. Dozens of floods backed up into the Willamette Valley, eroding 'scabland' channels, and depositing giant boulder gravel bars in areas of vigorous currents as well as bedded flood sand and silt in backwater areas. Also, large chunks of ice entrained from the breached glacier dam rafted hundreds of 'erratic' rocks, leaving them scattered among the flanking foothills and valley bottom. From several sources and our own mapping, we have compiled information on many of these features and depict them on physiographic maps derived from digital elevation models of the Portland Basin and Willamette Valley. These maps show maximum flood inundation levels, inundation levels associated with stratigraphic evidence of repeated floodings, distribution of flood deposits, and sites of ice-rafted erratics. Accompanying these maps, a database lists locations, elevations, and descriptions of approximately 400 ice-rafted erratics-most compiled from early 20th-century maps and notes of A.M. Piper and I.S. Allison.

Hydrologic and hydraulic analyses at Akin Branch and Cayce Valley Branch, Columbia, Tennessee

USGS Publications Warehouse

Outlaw, George S.

1993-01-01

The U.S. Geological Survey, in cooperation with the City of Columbia, Tennessee, conducted hydrologic and hydraulic analyses at Akin Branch and Cayce Valley Branch in the Little Bigby Creek watershed, Columbia, Tennessee, from 1990 through 1991. Results of the analyses can be used by city planners in the development of plans to replace several deteriorating and inadequate drainage structures. Akin Branch and Cayce Valley Branch drain small watersheds of 1.69 and 1.04 square miles, respectively. Flood discharges for 5-, lo-, and 25-year recurrence-interval storm events were calculated at the stream mouths using flood-frequency relations developed for use at small urban streams in Tennessee. For each stream, flood discharges at locations upstream from the mouth were calculated by subdividing the watershed and assigning a percentage of the discharge at the mouth, based on drainage area, to each subarea. Flood profiles for the selected recurrence-interval flood discharges were simulated for Akin Branch and Cayce Valley Branch for existing conditions and conditions that might exist if drainage improvements such as larger culverts and bridges and channel improvements are constructed. The results of the simulations were used to predict changes in flood elevations that might result from such drainage improvements. Analyses indicate that reductions in existing flood elevations of as much as 2.1 feet for the 5-year flood at some sites on Akin Branch and as much as 3.8 feet for the 5-year flood at some sites on Cayce Valley Branch might be expected with the drainage improvements.

77 FR 66788 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-07

...). Specifically, it addresses the following flooding sources: Demarest Kill, East Branch Hackensack River, Golf... Hackensack River, Golf Course Brook, Hackensack River, Minisceongo Creek, Nauraushaun Brook, North Branch... Town of Clarkstown. Old Mill Road. Approximately 600 feet +150 +151 downstream of Rockland Lake. Golf...

Amazon river flow regime and flood recessional agriculture: Flood stage reversals and risk of annual crop loss

NASA Astrophysics Data System (ADS)

Coomes, Oliver T.; Lapointe, Michel; Templeton, Michael; List, Geneva

2016-08-01

The annual flood cycle is an important driver of ecosystem structure and function in large tropical rivers such as the Amazon. Riparian peasant communities rely on river fishing and annual floodplain agriculture, closely adapted to the recession phase of the flood pulse. This article reports on a poorly documented but important challenge facing farmers practicing flood recessional agriculture along the Amazon river: frequent, unpredictable stage reversals (repiquetes) which threaten to ruin crops growing on channel bars. We assess the severity of stage reversals for rice production on exposed river mud bars (barreales) near Iquitos, Peru. Crop loss risk is estimated based on a quantitative analysis of 45 years of daily Amazon stage data and field data from floodplain communities nearby in the Muyuy archipelago, upstream of Iquitos. Rice varieties selected, elevations of silt rich bars where rice is sown, as well as planting and harvest dates are analyzed in the light of the timing, frequencies and amplitudes of observed stage reversals that have the potential to destroy growing rice. We find that unpredictable stage reversals can produce substantial crop losses and shorten significantly the length of average growing seasons on lower elevation river bars. The data reveal that local famers extend planting down to lower bar elevations where the mean probabilities of re-submergence before rice maturity (due to reversals) approach 50%, below which they implicitly consider that the risk of crop loss outweighs the potential reward of planting.

Potential of high resolution satellite imagery, remote weather data and 1D hydraulic modeling to evaluate flood areas in Gonaives, Haiti

NASA Astrophysics Data System (ADS)

Bozza, Andrea; Durand, Arnaud; Allenbach, Bernard; Confortola, Gabriele; Bocchiola, Daniele

2013-04-01

We present a feasibility study to explore potential of high-resolution imagery, coupled with hydraulic flood modeling to predict flooding risks, applied to the case study of Gonaives basins (585 km²), Haiti. We propose a methodology working at different scales, providing accurate results and a faster intervention during extreme flood events. The 'Hispaniola' island, in the Caribbean tropical zone, is often affected by extreme floods events. Floods are caused by tropical springs and hurricanes, and may lead to several damages, including cholera epidemics, as recently occurred, in the wake of the earthquake upon January 12th 2010 (magnitude 7.0). Floods studies based upon hydrological and hydraulic modeling are hampered by almost complete lack of ground data. Thenceforth, and given the noticeable cost involved in the organization of field measurement campaigns, the need for exploitation of remote sensing images data. HEC-RAS 1D modeling is carried out under different scenarios of available Digital Elevation Models. The DEMs are generated using optical remote sensing satellite (WorldView-1) and SRTM, combined with information from an open source database (Open Street Map). We study two recent flood episodes, where flood maps from remote sensing were available. Flood extent and land use have been assessed by way of data from SPOT-5 satellite, after hurricane Jeanne in 2004 and hurricane Hanna in 2008. A semi-distributed, DEM based hydrological model is used to simulate flood flows during the hurricanes. Precipitation input is taken from daily rainfall data derived from TRMM satellite, plus proper downscaling. The hydraulic model is calibrated using floodplain friction as tuning parameters against the observed flooded area. We compare different scenarios of flood simulation, and the predictive power of model calibration. The method provide acceptable results in depicting flooded areas, especially considering the tremendous lack of ground data, and show the potential of remote sensing information in prediction of flood events in this area, for the purpose of risk assessment and land use planning, and possibly for flood forecast during extreme events.

75 FR 31361 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-03

... source(s) elevation ground [caret] Elevation Communities affected in meters (MSL) Effective Modified... meter. ** BFEs to be changed include the listed downstream and upstream BFEs, and include BFEs located... Sea Level, rounded to the nearest 0.1 meter. ** BFEs to be changed include the listed downstream and...

75 FR 28511 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-21

... referenced ground [caret] Communities affected elevation Elevation in meters (MSL) Effective Modified... feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ** BFEs to be changed... upstream of the confluence with Williams Creek. Green River At Western Kentucky +400 +401 Town of Rockport...

76 FR 10253 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-24

... Depth in feet Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified... north of Talkeetna. Approximately 400 feet +394 downstream of the confluence of Whiskey Slough. Twister.... Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES Borough...

75 FR 31342 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-03

... referenced ground [caret] Communities affected elevation Elevation in meters (MSL) Effective Modified... Level, rounded to the nearest 0.1 meter. ** BFEs to be changed include the listed downstream and... ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ** BFEs to be changed include the...

Simulations of cataclysmic outburst floods from Pleistocene Glacial Lake Missoula

USGS Publications Warehouse

Denlinger, Roger P.; O'Connell, D. R. H.

2009-01-01

Using a flow domain that we constructed from 30 m digital-elevation model data of western United States and Canada and a two-dimensional numerical model for shallow-water flow over rugged terrain, we simulated outburst floods from Pleistocene Glacial Lake Missoula. We modeled a large, but not the largest, flood, using initial lake elevation at 1250 m instead of 1285 m. Rupture of the ice dam, centered on modern Lake Pend Oreille, catastrophically floods eastern Washington and rapidly fills the broad Pasco, Yakima, and Umatilla Basins. Maximum flood stage is reached in Pasco and Yakima Basins 38 h after the dam break, whereas maximum flood stage in Umatilla Basin occurs 17 h later. Drainage of these basins through narrow Columbia gorge takes an additional 445 h. For this modeled flood, peak discharges in eastern Washington range from 10 to 20 × 106 m3/s. However, constrictions in Columbia gorge limit peak discharges to 6 m3/s and greatly extend the duration of flooding. We compare these model results with field observations of scabland distribution and high-water indicators. Our model predictions of the locations of maximum scour (product of bed shear stress and average flow velocity) match the distribution of existing scablands. We compare model peak stages to high-water indicators from the Rathdrum-Spokane valley, Walulla Gap, and along Columbia gorge. Though peak stages from this less-than-maximal flood model attain or exceed peak-stage indicators along Rathdrum-Spokane valley and along Columbia gorge, simulated peak stages near Walulla Gap are 10–40 m below observed peak-stage indicators. Despite this discrepancy, our match to field observations in most of the region indicates that additional sources of water other than Glacial Lake Missoula are not required to explain the Missoula floods.

Contrasting Impact of Floodwaters on Coastal Biogeochemistry in the Great Barrier Reef Ecosystem

NASA Astrophysics Data System (ADS)

Crosswell, J.; Carlin, G.; Steven, A. D.; Franklin, H.

2017-12-01

Delivery of terrestrial nutrients and organic material to Great Barrier Reef (GBR) ecosystem is dominated by episodic floods, and the biogeochemical impact of these events is expected to change under future climatic and man-made stressors. Here we compare the biogeochemical response of coastal waters to floods from two of the largest catchment in northeast Australia, the Fitzroy and Normanby River basins. The Fitzroy catchment is dominated by agriculture, principally grazing, whereas the Normanby is regarded as relatively pristine. High-resolution spatial surveys showed that flood plumes in both regions extended 30-100 km seaward and along the coast, reaching interior reefs and islands of the GBR. Floodwaters from both catchments were characterized by elevated nutrients and dissolved organic carbon (DOC), but the fate of flood-borne material in coastal waters showed significant differences between the two systems. In the Normanby, nutrients were rapidly removed near the estuary mouth and chlorophyll a was low throughout the adjacent Princess Charlotte Bay. Elevated DOC levels persisted in the Normanby flood plume, but high dissolved oxygen and low CO2 throughout a stratified water column suggested that the flood-borne organic matter was recalcitrant. By contrast, there was a clear source of DOC and nutrients in the hypoxic bottom waters of the Fitzroy flood plume, suggesting that the flood-borne particulate organic matter was highly labile. Decoupling of autotrophic surface waters from heterotrophic bottom waters in the Fitzroy plume supported a large phytoplankton bloom that extended >100 km and led to low pH and low light availability at nearby reefs. The contrasting impact of major floods in these two coastal systems appeared to be primarily driven by the quality of flood-borne organic matter, as well as differences in coastal morphology.

Terrestrial laser scanning of anthropogenic beach berms for urban flood defense

NASA Astrophysics Data System (ADS)

Sanders, B. F.; Schubert, J.; Gallien, T.; Shakeri Majd, M.

2013-12-01

Globally, over 20 million people reside below present high tide levels and as many as 200 million are vulnerable to flooding during extreme events. In California, coastal flooding is driven by a combination of factors such as high astronomical tides, waves, storm surge, and other fluctuations such as those caused by the El Nino Southern Oscillation (ENSO), and climate change is likely to exacerbate those factors testing the limits of coastal flood defenses. Beaches provide natural flood protection during storms by mitigating the effects of high water levels and wave runup, and a process known as beach berming can be used to temporarily enhance the ability of beaches to withstand overtopping. In cases where beaches serve as primary protection for development, anthropogenic berms may represent an attractive management option for temporarily addressing future flood hazards. Terrestrial laser scanning (TLS) or lidar has emerged as a valuable technology for capturing the three dimensional geometry of complex surfaces and objects, and in the context of coastal flood prediction mobile TLS could prove invaluable by quickly mapping beach topography before an imminent flood threat and reducing associated uncertainties in coastal flood forecasting systems. The research presented here highlights the results of a field campaign to document the initial conditions and dynamic erosion of anthropogenic berms using TLS. On three occasions in February and March of 2012, a prototype berm was constructed on the foreshore of the city of Newport Beach, CA at low tide, and was scanned to document its initial shape, and then scanned in near-continuous fashion with the rising tide to characterize its subsequent erosion. The purpose is two-fold: (1) to measure the performance of the TLS system relative to accuracy and assess strengths and drawbacks that are likely to bear on the suitability of this technology to support flood prediction as described above, and (2) to develop a better understanding of how typical southern California berms respond to hydrodynamic stresses (rising tides and waves). Near continuous scanning leads to a 4D model (3 spatial coordinates plus time) of the berm that documents its gradual erosion, including a characterization of how the berm crest and volume change over time, which offers primary data on how anthropogenic berms can be expected to perform during a flood event. Results reveal that TLS, when referenced to a temporary bench mark leveled to within 1.5 cm by RTK-GPS, achieves an absolute vertical accuracy of less than 3 cm (VRMSE) with a scan resolution of 10 cm or finer. In regards to berm morphodynamics, a near-linear increase in tide elevation over two hours caused a non-linear lowering of the berm crest with time, characterized first by a gradual and then by a rapid change. The overall erosion of the berm correlates best with the swash elevation in relation to the berm toe elevation. Across the three berm experiments, erosion begins when the swash elevation is about 13% below the toe of the berm, relative to the initial berm height, and the berm is overtopped when the swash elevation is 25-30% of the initial berm height and the berm is 70-75% eroded by volume.

Coarse Resolution SAR Imagery to Support Flood Inundation Models in Near Real Time

NASA Astrophysics Data System (ADS)

Di Baldassarre, Giuliano; Schumann, Guy; Brandimarte, Luigia; Bates, Paul

2009-11-01

In recent years, the availability of new emerging data (e.g. remote sensing, intelligent wireless sensors, etc) has led to a sudden shift from a data-sparse to a data-rich environment for hydrological and hydraulic modelling. Furthermore, the increased socioeconomic relevance of river flood studies has motivated the development of complex methodologies for the simulation of the hydraulic behaviour of river systems. In this context, this study aims at assessing the capability of coarse resolution SAR (Synthetic Aperture Radar) imagery to support and quickly validate flood inundation models in near real time. A hydraulic model of a 98km reach of the River Po (Italy), previously calibrated on a high-magnitude flood event with extensive and high quality field data, is tested using a SAR flood image, acquired and processed in near real time, during the June 2008 low-magnitude event. Specifically, the image is an acquisition by the ENVISAT-ASAR sensor in wide swath mode and has been provided through ESA (European Space Agency) Fast Registration system at no cost 24 hours after the acquisition. The study shows that the SAR image enables validation and improvement of the model in a time shorter than the flood travel time. This increases the reliability of model predictions (e.g. water elevation and inundation width along the river reach) and, consequently, assists flood management authorities in undertaking the necessary prevention activities.

Integration of SRTM and TRMM date into the GIS-based hydrological model for the purpose of flood modelling

NASA Astrophysics Data System (ADS)

Akbari, A.; Abu Samah, A.; Othman, F.

2012-04-01

Due to land use and climate changes, more severe and frequent floods occur worldwide. Flood simulation as the first step in flood risk management can be robustly conducted with integration of GIS, RS and flood modeling tools. The primary goal of this research is to examine the practical use of public domain satellite data and GIS-based hydrologic model. Firstly, database development process is described. GIS tools and techniques were used in the light of relevant literature to achieve the appropriate database. Watershed delineation and parameterizations were carried out using cartographic DEM derived from digital topography at a scale of 1:25 000 with 30 m cell size and SRTM elevation data at 30 m cell size. The SRTM elevation dataset is evaluated and compared with cartographic DEM. With the assistance of statistical measures such as Correlation coefficient (r), Nash-Sutcliffe efficiency (NSE), Percent Bias (PBias) or Percent of Error (PE). According to NSE index, SRTM-DEM can be used for watershed delineation and parameterization with 87% similarity with Topo-DEM in a complex and underdeveloped terrains. Primary TRMM (V6) data was used as satellite based hytograph for rainfall-runoff simulation. The SCS-CN approach was used for losses and kinematic routing method employed for hydrograph transformation through the reaches. It is concluded that TRMM estimates do not give adequate information about the storms as it can be drawn from the rain gauges. Event-based flood modeling using HEC-HMS proved that SRTM elevation dataset has the ability to obviate the lack of terrain data for hydrologic modeling where appropriate data for terrain modeling and simulation of hydrological processes is unavailable. However, TRMM precipitation estimates failed to explain the behavior of rainfall events and its resultant peak discharge and time of peak.

Duration and Frequency Analysis of Lowland Flooding in Western Murfreesboro, Rutherford County, Tennessee, 1998-2000

USGS Publications Warehouse

Law, George S.

2002-01-01

Periodic flooding occurs at lowlands and sinkholes in and adjacent to the flood plain of the West Fork Stones River in the western part of Murfreesboro, Tennessee. Flooding in this area commonly occurs during the winter months from December through March. The maximum water level that flood waters will reach in a lowland or sinkhole is controlled by the elevation of the land surrounding the site or the overflow outlet. Maximum water levels, independent of overflow from the river, were estimated to be reached in lowlands and sinkholes in the study area every 1 to 4 years. Minor overflow from the West Fork Stones River (less than 1 foot in depth) into the study area has been estimated to occur every 10 to 20 years. Moderate overflow from the river (1 to 2 feet in depth) occurs on average every 20 to 50 years, while major river overflow (in excess of 2 feet in depth) can be expected every 50 years. Rainfall information for the area, and streamflow and water-level measurements from the West Fork Stones River, lowlands, sinkholes, caves, and wells in the study area were used to develop a flood-prone area map, independent of overflow from the river, for the study area. Water-level duration and frequency relations, independent of overflow from the river, were estimated for several lowlands, sinkholes, and wells in the study area. These relations are used to characterize flooding in lowland areas of western Murfreesboro, Rutherford County, Tennessee.

20. Top 30/3. Plan of exposed substructure elevations. Wyoming ...

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

20. Top 30/3. Plan of exposed substructure elevations. - Wyoming Valley Flood Control System, Woodward Pumping Station, East of Toby Creek crossing by Erie-Lackawanna Railroad, Edwardsville, Luzerne County, PA

76 FR 58411 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-21

... rates for new buildings and their contents. DATES: The effective dates for these modified BFEs are... buildings built after these elevations are made final, and for the contents in those buildings. The changes...

Estimated flood-inundation maps for Cowskin Creek in western Wichita, Kansas

USGS Publications Warehouse

Studley, Seth E.

2003-01-01

The October 31, 1998, flood on Cowskin Creek in western Wichita, Kansas, caused millions of dollars in damages. Emergency management personnel and flood mitigation teams had difficulty in efficiently identifying areas affected by the flooding, and no warning was given to residents because flood-inundation information was not available. To provide detailed information about future flooding on Cowskin Creek, high-resolution estimated flood-inundation maps were developed using geographic information system technology and advanced hydraulic analysis. Two-foot-interval land-surface elevation data from a 1996 flood insurance study were used to create a three-dimensional topographic representation of the study area for hydraulic analysis. The data computed from the hydraulic analyses were converted into geographic information system format with software from the U.S. Army Corps of Engineers' Hydrologic Engineering Center. The results were overlaid on the three-dimensional topographic representation of the study area to produce maps of estimated flood-inundation areas and estimated depths of water in the inundated areas for 1-foot increments on the basis of stream stage at an index streamflow-gaging station. A Web site (http://ks.water.usgs.gov/Kansas/cowskin.floodwatch) was developed to provide the public with information pertaining to flooding in the study area. The Web site shows graphs of the real-time streamflow data for U.S. Geological Survey gaging stations in the area and monitors the National Weather Service Arkansas-Red Basin River Forecast Center for Cowskin Creek flood-forecast information. When a flood is forecast for the Cowskin Creek Basin, an estimated flood-inundation map is displayed for the stream stage closest to the National Weather Service's forecasted peak stage. Users of the Web site are able to view the estimated flood-inundation maps for selected stages at any time and to access information about this report and about flooding in general. Flood recovery teams also have the ability to view the estimated flood-inundation map pertaining to the most recent flood. The availability of these maps and the ability to monitor the real-time stream stage through the U.S. Geological Survey Web site provide emergency management personnel and residents with information that is critical for evacuation and rescue efforts in the event of a flood as well as for post-flood recovery efforts.

Response of Schoenoplectus acutus and Schoenoplectus californicus at different life-history stages to hydrologic regime

USGS Publications Warehouse

Sloey, Taylor M; Howard, Rebecca J.; Hester, Mark W.

2016-01-01

For wetland restoration success to be maximized, restoration managers need better information regarding how the frequency, depth, and duration of flooding affect soil chemistry and the survival, growth, and morphology of targeted plant species. In a greenhouse study we investigated the impact of four different flooding durations (0 %, 40 %, 60 %, and 100 %) on soil physicochemistry and the responses of seedlings and adults of two species of emergent wetland macrophytes commonly used in restoration efforts (Schoenoplectus acutus and Schoenoplectus californicus). The longest flooding duration, which created more reducing soil conditions, resulted in significantly reduced survival of S. acutus adults (34 ± 21 % survival) and complete mortality of seedlings of both species. Schoenoplectus californicus adults exhibited higher flooding tolerance, showing little impact of flooding on morphology and physiology. A companion field study indicated that S. californicus maintained stem strength regardless of flooding duration or depth, supporting the greenhouse study results. This information serves to improve our understanding of the ecological differences between these species as well as provide restoration managers with better guidelines for targeted elevation and hydrologic regimes for these species in order to enhance the success of restoration plantings and better predict restoration site development.

Flood prevention dams for arid regions at a micro-scale sub-catchment, case study: Tabuk, Saudi Arabia.

PubMed

Abushandi, Eyad

2016-12-01

Unexpected flash flooding is one of the periodic hydrological problems affecting the city of Tabuk in Saudi Arabia. The region has high potential for floods as it suffers high rainfall intensity in a short time and also has high urbanization rates and topographic complexity. Constructing flood prevention dams is one option to solve this problem. A cost-effective design requires a detailed feasibility study and analysis for the selection of suitable sites. The aim of this study was to develop a method for selecting a suitable site for flood protection dams in the Abu Saba'a district, the most affected part of the city of Tabuk during the flash flood in January 2013. Spatial analysis was applied using Landsat Thematic Mapper images and Shuttle Radar Topography Mission digital elevation model to select a site in the Abu Saba'a area. A simple model using ArcGIS was built including all suggested parameters. The results showed the best site for a dam was 2 km distance backfrom the area, where all parameter values matched. The results showed that the dynamic properties of land cover can affect site selection. It is therefore suggested that more field and hydrological data should be gathered for greater accuracy.

Colombia Mi Pronostico Flood Application: Updating and Improving the Mi Pronostico Flood Web Application to Include an Assessment of Flood Risk

NASA Technical Reports Server (NTRS)

Rushley, Stephanie; Carter, Matthew; Chiou, Charles; Farmer, Richard; Haywood, Kevin; Pototzky, Anthony, Jr.; White, Adam; Winker, Daniel

2014-01-01

Colombia is a country with highly variable terrain, from the Andes Mountains to plains and coastal areas, many of these areas are prone to flooding disasters. To identify these risk areas NASA's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) was used to construct a digital elevation model (DEM) for the study region. The preliminary risk assessment was applied to a pilot study area, the La Mosca River basin. Precipitation data from the National Aeronautics and Space Administration (NASA) Tropical Rainfall Measuring Mission (TRMM)'s near-real-time rainfall products as well as precipitation data from the Instituto de Hidrologia, Meteorologia y Estudios Ambientales (the Institute of Hydrology, Meteorology and Environmental Studies, IDEAM) and stations in the La Mosca River Basin were used to create rainfall distribution maps for the region. Using the precipitation data and the ASTER DEM, the web application, Mi Pronóstico, run by IDEAM, was updated to include an interactive map which currently allows users to search for a location and view the vulnerability and current weather and flooding conditions. The geospatial information was linked to an early warning system in Mi Pronóstico that can alert the public of flood warnings and identify locations of nearby shelters.

Strength in Numbers: Describing the Flooded Area of Isolated Wetlands

USGS Publications Warehouse

Lee, Terrie M.; Haag, Kim H.

2006-01-01

Thousands of isolated, freshwater wetlands are scattered across the karst1 landscape of central Florida. Most are small (less than 15 acres), shallow, marsh and cypress wetlands that flood and dry seasonally. Wetland health is threatened when wetland flooding patterns are altered either by human activities, such as land-use change and ground-water pumping, or by changes in climate. Yet the small sizes and vast numbers of isolated wetlands in Florida challenge our efforts to characterize them collectively as a statewide water resource. In the northern Tampa Bay area of west-central Florida alone, water levels are measured monthly in more than 400 wetlands by the Southwest Florida Water Management Distirct (SWFWMD). Many wetlands have over a decade of measurements. The usefulness of long-term monitoring of wetland water levels would greatly increase if it described not just the depth of water at a point in the wetland, but also the amount of the total wetland area that was flooded. Water levels can be used to estimate the flooded area of a wetland if the elevation contours of the wetland bottom are determined by bathymetric mapping. Despite the recognized importance of the flooded area to wetland vegetation, bathymetric maps are not available to describe the flooded areas of even a representative number of Florida's isolated wetlands. Information on the bathymetry of isolated wetlands is rare because it is labor intensive to collect the land-surface elevation data needed to create the maps. Five marshes and five cypress wetlands were studied by the U.S. Geological Survey (USGS) during 2000 to 2004 as part of a large interdisciplinary study of isolated wetlands in central Florida. The wetlands are located either in municipal well fields or on publicly owned lands (fig. 1). The 10 wetlands share similar geology and climate, but differ in their ground-water settings. All have historical water-level data and multiple vegetation surveys. A comprehensive report by Haag and others (2005) documents bathymetric mapping approaches, the frequency of flooding in different areas of the wetlands, and the relation between flooding and vegetation in these wetlands. This fact sheet describes bathymetric mapping approaches and partial results from two natural marshes (Hillsborough River State Park Marsh, and Green Swamp Marsh) and one impaired marsh (W-29 Marsh) that is located on a municipal well field and is affected by ground-water withdrawals. (fig. 1).

The Role of Eolian Sediment in the Preservation of Archeologic Sites Along the Colorado River Corridor in Grand Canyon National Park, Arizona

USGS Publications Warehouse

Draut, Amy E.; Rubin, David M.

2008-01-01

Since the closure of Glen Canyon Dam in 1963, the natural hydrologic and sedimentary systems along the Colorado River in the Grand Canyon reach have changed substantially (see, for example, Andrews, 1986; Johnson and Carothers, 1987; Webb and others, 1999b; Rubin and others, 2002; Topping and others, 2003; Wright and others, 2005; Hazel and others, 2006b). The dam has reduced the fluvial sediment supply at the upstream boundary of Grand Canyon National Park by about 95 percent. Regulation of river discharge by dam operations has important implications for the storage and redistribution of sediment in the Colorado River corridor. In the absence of floods, sediment is not deposited at elevations that regularly received sediment before dam closure. Riparian vegetation has colonized areas at lower elevations than in predam time when annual floods removed young vegetation (Turner and Karpiscak, 1980). Together, these factors have caused a systemwide decrease in the size and number of subaerially exposed fluvial sand deposits since the 1960s, punctuated by episodic aggradation during the exceptional high-flow intervals in 1983-84, 1996, and 2004 and by sediment input from occasional tributary floods (Beus and others, 1985; Schmidt and Graf, 1987; Kearsley and others, 1994; Hazel and others, 1999; Schmidt and others, 2004; Wright and others, 2005). When the Bureau of Reclamation sponsored the creation of the Glen Canyon Environmental Studies (GCES) research initiative in 1982, research objectives included physical and biologic resources, whereas the effects of dam operations on cultural resources were not addressed (Fairley and others, 1994; Fairley, 2003). In the early 1980s, it was widely believed that because few archeologic sites were preserved within the river's annual-flood zone, cultural features would not be greatly affected by dam operations. Recent studies, however, indicate that alterations in the flow and sediment load of the Colorado River by Glen Canyon Dam operations may affect archeologic sites within the river corridor, even above the annual flood limit (Hereford and others, 1993, Yeatts, 1996, 1997; Thompson and Potochnik, 2000; Draut and others, 2005). (The annual-flood zone is defined here by the mean annual predam flood of 2,410 m3/s; the 'predam flood limit', the highest elevation at which fluvial deposits are present locally, was approximately equivalent to a rare, major flood of 8,500 m3/s; Topping and others, 2003.) Of about 500 archeologic sites documented between Glen Canyon Dam and Separation Canyon (255 river miles), more than 330 are considered to be within the area of potential effect (APE) of dam operations (Fairley and others, 1994; Neal and others, 2000; Fairley, 2005). The APE was designated by the National Park Service (NPS) to include the area below the peak stage of the 1884 flood; though previously believed to have reached 8,490 m3/s, this flood was shown by Topping and others (2003) to have peaked at 5,940 m3/s. Archeologic research and monitoring in Grand Canyon National Park focus increasingly on the potential effects of Glen Canyon Dam operations on the landscape in which these sites exist. Many archeologic sites in or on sedimentary deposits are being eroded, owing to eolian deflation and gully incision (Leap and others, 2000; Neal and others, 2000; Fairley, 2003, 2005). Hereford and others (1993) first suggested that gully incision of sedimentary deposits, and the base level to which small drainage systems respond, were linked to dam operations; they hypothesized that pronounced arroyo incision, which occurs during rainfall runoff, was caused by lowering of the effective base level at the mouths of ephemeral drainages to meet the new postdam elevation of high-flow sediment deposition, about 3 to 4 m below the lowest predam alluvial terraces. Thompson and Potochnik (2000) modified that hypothesis to include the restorative effects of fluvial deposition in the mouths of gullies and ar

Bathymetric survey of the Cayuga Inlet flood-control channel and selected tributaries in Ithaca, New York, 2016

USGS Publications Warehouse

Wernly, John F.; Nystrom, Elizabeth A.; Coon, William F.

2017-09-08

From July 14 to July 20, 2016, the U.S. Geological Survey, in cooperation with the City of Ithaca, New York, and the New York State Department of State, surveyed the bathymetry of the Cayuga Inlet flood-control channel and the mouths of selected tributaries to Cayuga Inlet and Cayuga Lake in Ithaca, N.Y. The flood-control channel, built by the U.S. Army Corps of Engineers between 1965 and 1970, was designed to convey flood flows from the Cayuga Inlet watershed through the City of Ithaca and minimize possible flood damages. Since that time, the channel has infrequently been maintained by dredging, and sediment accumulation and resultant shoaling have greatly decreased the conveyance of the channel and its navigational capability.U.S. Geological Survey personnel collected bathymetric data by using an acoustic Doppler current profiler. The survey produced a dense dataset of water depths that were converted to bottom elevations. These elevations were then used to generate a geographic information system bathymetric surface. The bathymetric data and resultant bathymetric surface show the current condition of the channel and provide the information that governmental agencies charged with maintaining the Cayuga Inlet for flood-control and navigational purposes need to make informed decisions regarding future maintenance measures.

Two-dimensional simulation of the June 11, 2010, flood of the Little Missouri River at Albert Pike Recreational Area, Ouachita National Forest, Arkansas

USGS Publications Warehouse

Wagner, Daniel M.

2013-01-01

In the early morning hours of June 11, 2010, substantial flooding occurred at Albert Pike Recreation Area in the Ouachita National Forest of west-central Arkansas, killing 20 campers. The U.S. Forest Service needed information concerning the extent and depth of flood inundation, the water velocity, and flow paths throughout Albert Pike Recreation Area for the flood and for streamflows corresponding to annual exceedence probabilities of 1 and 2 percent. The two-dimensional flow model Fst2DH, part of the Federal Highway Administration’s Finite Element Surface-water Modeling System, and the graphical user interface Surface-water Modeling System (SMS) were used to perform a steady-state simulation of the flood in a 1.5-mile reach of the Little Missouri River at Albert Pike Recreation Area. Peak streamflows of the Little Missouri River and tributary Brier Creek served as inputs to the simulation, which was calibrated to the surveyed elevations of high-water marks left by the flood and then used to predict flooding that would result from streamflows corresponding to annual exceedence probabilities of 1 and 2 percent. The simulated extent of the June 11, 2010, flood matched the observed extent of flooding at Albert Pike Recreation Area. The mean depth of inundation in the camp areas was 8.5 feet in Area D, 7.4 feet in Area C, 3.8 feet in Areas A, B, and the Day Use Area, and 12.5 feet in Lowry’s Camp Albert Pike. The mean water velocity was 7.2 feet per second in Area D, 7.6 feet per second in Area C, 7.2 feet per second in Areas A, B, and the Day Use Area, and 7.6 feet per second in Lowry’s Camp Albert Pike. A sensitivity analysis indicated that varying the streamflow of the Little Missouri River had the greatest effect on simulated water-surface elevation, while varying the streamflow of tributary Brier Creek had the least effect. Simulated water-surface elevations were lower than those modeled by the U.S. Forest Service using the standard-step method, but the comparison between the two was favorable with a mean absolute difference of 0.58 feet in Area C and 0.32 feet in Area D. Results of a HEC-RAS model of the Little Missouri River watershed upstream from the U.S. Geological Survey streamflow-gaging station near Langley showed no difference in mean depth in the areas in common between the models, and a difference in mean velocity of only 0.5 foot per second. Predictions of flooding that would result from streamflows corresponding to annual exceedence probabilities of 1 and 2 percent indicated that the extent of inundation of the June 11, 2010, flood exceeded that of the 1 percent flood, and that for both the 1 and 2 percent floods, all of Areas C and D, and parts of Areas A, B, and the Day Use Area were inundated. Predicted water-surface elevations for the 1 and 2 percent floods were approximately 1 foot lower than those predicted by the U.S. Forest Service using a standard-step model.

44 CFR 67.8 - Appeal procedure.

Code of Federal Regulations, 2010 CFR

2010-10-01

... technical or scientific data submitted by the community that tend to negate or contradict the information... FLOOD ELEVATION DETERMINATIONS § 67.8 Appeal procedure. (a) If a community appeals the proposed flood... to an independent scientific body or appropriate Federal agency for advice. (c) The final...

44 CFR 67.8 - Appeal procedure.

Code of Federal Regulations, 2011 CFR

2011-10-01

... technical or scientific data submitted by the community that tend to negate or contradict the information... FLOOD ELEVATION DETERMINATIONS § 67.8 Appeal procedure. (a) If a community appeals the proposed flood... to an independent scientific body or appropriate Federal agency for advice. (c) The final...

Process-based model with flood control measures towards more realistic global flood modeling

NASA Astrophysics Data System (ADS)

Tang, Q.; Zhang, X.; Wang, Y.; Mu, M.; Lv, A.; Li, Z.

2017-12-01

In the profoundly human-influenced era, the Anthropocene, increased amount of land was developed in flood plains and many flood control measures were implemented to protect people and infrastructures placed in the flood-prone areas. These human influences (for example, dams and dykes) have altered peak streamflow and flood risk, and are already an integral part of flood. However, most of the process-based flood models have yet to taken into account the human influences. In this study, we used a hydrological model together with an advanced hydrodynamic model to assess flood risk at the Baiyangdian catchment. The Baiyangdian Lake is the largest shallow freshwater lake in North China, and it was used as a flood storage area in the past. A new development hub for the Beijing-Tianjin-Hebei economic triangle, namely the Xiongan new area, was recently established in the flood-prone area around the lake. The shuttle radar topography mission (SRTM) digital elevation model (DEMs) was used to parameterize the hydrodynamic model simulation, and the inundation estimates were compared with published flood maps and observed inundation area during the extreme historical flood events. A simple scheme was carried out to consider the impacts of flood control measures, including the reservoirs in the headwaters and the dykes to be built. By comparing model simulations with and without the influences of flood control measures, we demonstrated the importance of human influences in altering the inundated area and depth under design flood conditions. Based on the SRTM DEM and dam and reservoir data in the Global Reservoir and Dam (GRanD) database, we further discuss the potential to develop a global flood model with human influences.

Estimation of design floods in ungauged catchments using a regional index flood method. A case study of Lake Victoria Basin in Kenya

NASA Astrophysics Data System (ADS)

Nobert, Joel; Mugo, Margaret; Gadain, Hussein

Reliable estimation of flood magnitudes corresponding to required return periods, vital for structural design purposes, is impacted by lack of hydrological data in the study area of Lake Victoria Basin in Kenya. Use of regional information, derived from data at gauged sites and regionalized for use at any location within a homogenous region, would improve the reliability of the design flood estimation. Therefore, the regional index flood method has been applied. Based on data from 14 gauged sites, a delineation of the basin into two homogenous regions was achieved using elevation variation (90-m DEM), spatial annual rainfall pattern and Principal Component Analysis of seasonal rainfall patterns (from 94 rainfall stations). At site annual maximum series were modelled using the Log normal (LN) (3P), Log Logistic Distribution (LLG), Generalized Extreme Value (GEV) and Log Pearson Type 3 (LP3) distributions. The parameters of the distributions were estimated using the method of probability weighted moments. Goodness of fit tests were applied and the GEV was identified as the most appropriate model for each site. Based on the GEV model, flood quantiles were estimated and regional frequency curves derived from the averaged at site growth curves. Using the least squares regression method, relationships were developed between the index flood, which is defined as the Mean Annual Flood (MAF) and catchment characteristics. The relationships indicated area, mean annual rainfall and altitude were the three significant variables that greatly influence the index flood. Thereafter, estimates of flood magnitudes in ungauged catchments within a homogenous region were estimated from the derived equations for index flood and quantiles from the regional curves. These estimates will improve flood risk estimation and to support water management and engineering decisions and actions.

Street floods in Metro Manila and possible solutions.

PubMed

Lagmay, Alfredo Mahar; Mendoza, Jerico; Cipriano, Fatima; Delmendo, Patricia Anne; Lacsamana, Micah Nieves; Moises, Marc Anthony; Pellejera, Nicanor; Punay, Kenneth Niño; Sabio, Glenn; Santos, Laurize; Serrano, Jonathan; Taniza, Herbert James; Tingin, Neil Eneri

2017-09-01

Urban floods from thunderstorms cause severe problems in Metro Manila due to road traffic. Using Light Detection and Ranging (LiDAR)-derived topography, flood simulations and anecdotal reports, the root of surface flood problems in Metro Manila is identified. Majority of flood-prone areas are along the intersection of creeks and streets located in topographic lows. When creeks overflow or when rapidly accumulated street flood does not drain fast enough to the nearest stream channel, the intersecting road also gets flooded. Possible solutions include the elevation of roads or construction of well-designed drainage structures leading to the creeks. Proposed solutions to the flood problem of Metro Manila may avoid paralyzing traffic problems due to short-lived rain events, which according to Japan International Cooperation Agency (JICA) cost the Philippine economy 2.4billionpesos/day. Copyright © 2017. Published by Elsevier B.V.

75 FR 55480 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-13

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Pickens County, Alabama... Level, rounded to the nearest 0.1 meter. ADDRESSES City of Memphis Maps are available for inspection at.... Approximately 2,400 feet +415 west of the intersection of Bonnie Road and Cooley Lane. West Tributary...

75 FR 31368 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-03

... referenced ground [caret] Communities affected elevation Elevation in meters (MSL) Effective Modified Santa.... Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ** BFEs to be... Vertical Datum. Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter...

77 FR 21476 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-10

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Randolph County... Vertical Datum. Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter.... [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES City of Beebe Maps are available for...

76 FR 39011 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-05

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Rio Grande County... Unincorporated Areas of the Rio Grande, Rio Grande County. approximately 400 feet north of U.S. Route 160... Vertical Datum. Depth in feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter...

77 FR 7540 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Sebastian County... Level, rounded to the nearest 0.1 meter. ADDRESSES City of Fort Smith Maps are available for inspection.... [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES City of Rolling Fork Maps are...

75 FR 44155 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-28

... Communities affected elevation feet above ground [caret] Elevation in meters (MSL) Modified Coffee County... meter. ADDRESSES City of Elba Maps are available for inspection at 200 Buford Street, Elba, AL 36323.... Approximately 1,400 feet +7776 upstream of West Grimes Creek Road. Junction Creek At Pleasant Drive in Durango...

75 FR 29253 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-25

.... Approximately 100 feet None +109 downstream of State Road 77. Flat Creek At the confluence with None +50...: * Elevation in feet (NGVD) + Elevation in feet (NAVD) Depth in feet above State City/town/county Source of... Virginia City of Hampton......... Newmarket Creek Approximately 275 feet downstream of Big Bethel Road...

78 FR 14697 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-07

... Communities affected elevation above ground [caret] Elevation in meters (MSL) Modified Cecil County, Maryland... 1 to Stone Run At the Stone Run +271 Town of Rising Sun, confluence. Unincorporated Areas of Cecil County. Approximately 460 feet +359 downstream of Pierce Road. Tributary 2 to Stone Run At the Stone Run...

National Program for Inspection of Non-Federal Dams, Goose Pond Dam (NH 00101), Connecticut River Basin, Keene, New Hampshire. Phase I Inspection Report.

DTIC Science & Technology

1980-02-01

exceeded by floods _ greater than 6 percent of the Probable Maximum Flood ( PKF ), the test flood for spillway adequacy. Our screening criteria specifies...capacity at the top of the * dam (elevation 637) is 195 cfs or six percent of the routed O . Test Flood peak outflow. The dam is in FAIR condition at the...environment of the structure. It is .important to note that the condition of a dam depends on numerous and constantly changing internal and external

RASOR flood modelling

NASA Astrophysics Data System (ADS)

Beckers, Joost; Buckman, Lora; Bachmann, Daniel; Visser, Martijn; Tollenaar, Daniel; Vatvani, Deepak; Kramer, Nienke; Goorden, Neeltje

2015-04-01

Decision making in disaster management requires fast access to reliable and relevant information. We believe that online information and services will become increasingly important in disaster management. Within the EU FP7 project RASOR (Rapid Risk Assessment and Spatialisation of Risk) an online platform is being developed for rapid multi-hazard risk analyses to support disaster management anywhere in the world. The platform will provide access to a plethora of GIS data that are relevant to risk assessment. It will also enable the user to run numerical flood models to simulate historical and newly defined flooding scenarios. The results of these models are maps of flood extent, flood depths and flow velocities. The RASOR platform will enable to overlay historical event flood maps with observations and Earth Observation (EO) imagery to fill in gaps and assess the accuracy of the flood models. New flooding scenarios can be defined by the user and simulated to investigate the potential impact of future floods. A series of flood models have been developed within RASOR for selected case study areas around the globe that are subject to very different flood hazards: • The city of Bandung in Indonesia, which is prone to fluvial flooding induced by heavy rainfall. The flood hazard is exacerbated by land subsidence. • The port of Cilacap on the south coast of Java, subject to tsunami hazard from submarine earthquakes in the Sunda trench. • The area south of city of Rotterdam in the Netherlands, prone to coastal and/or riverine flooding. • The island of Santorini in Greece, which is subject to tsunamis induced by landslides. Flood models have been developed for each of these case studies using mostly EO data, augmented by local data where necessary. Particular use was made of the new TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) product from the German Aerospace centre (DLR) and EADS Astrium. The presentation will describe the flood models and the flooding scenarios that can be defined by the RASOR end user to support risk management in each area. Ongoing work for three more case studies (Haiti, Po valley in Italy and Jakarta, Indonesia) will also be discussed.

77 FR 19112 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-30

... Communities affected [caret] Elevation in meters (MSL) Modified Sumter County, Alabama, and Incorporated Areas... feet above ground. [caret] Mean Sea Level, rounded to the nearest 0.1 meter. ADDRESSES Town of Epes... Avenue. [[Page 19114

Development of a channel classification to evaluate potential for cottonwood restoration, lower segments of the Middle Missouri River, South Dakota and Nebraska

USGS Publications Warehouse

Jacobson, Robert B.; Elliott, Caroline M.; Huhmann, Brittany L.

2010-01-01

This report documents development of a spatially explicit river and flood-plain classification to evaluate potential for cottonwood restoration along the Sharpe and Fort Randall segments of the Middle Missouri River. This project involved evaluating existing topographic, water-surface elevation, and soils data to determine if they were sufficient to create a classification similar to the Land Capability Potential Index (LCPI) developed by Jacobson and others (U.S. Geological Survey Scientific Investigations Report 2007–5256) and developing a geomorphically based classification to apply to evaluating restoration potential.Existing topographic, water-surface elevation, and soils data for the Middle Missouri River were not sufficient to replicate the LCPI. The 1/3-arc-second National Elevation Dataset delineated most of the topographic complexity and produced cumulative frequency distributions similar to a high-resolution 5-meter topographic dataset developed for the Lower Missouri River. However, lack of bathymetry in the National Elevation Dataset produces a potentially critical bias in evaluation of frequently flooded surfaces close to the river. High-resolution soils data alone were insufficient to replace the information content of the LCPI. In test reaches in the Lower Missouri River, soil drainage classes from the Soil Survey Geographic Database database correctly classified 0.8–98.9 percent of the flood-plain area at or below the 5-year return interval flood stage depending on state of channel incision; on average for river miles 423–811, soil drainage class correctly classified only 30.2 percent of the flood-plain area at or below the 5-year return interval flood stage. Lack of congruence between soil characteristics and present-day hydrology results from relatively rapid incision and aggradation of segments of the Missouri River resulting from impoundments and engineering. The most sparsely available data in the Middle Missouri River were water-surface elevations. Whereas hydraulically modeled water-surface elevations were available at 1.6-kilometer intervals in the Lower Missouri River, water-surface elevations in the Middle Missouri River had to be interpolated between streamflow-gaging stations spaced 3–116 kilometers. Lack of high-resolution water-surface elevation data precludes development of LCPI-like classification maps.An hierarchical river classification framework is proposed to provide structure for a multiscale river classification. The segment-scale classification presented in this report is deductive and based on presumed effects of dams, significant tributaries, and geological (and engineered) channel constraints. An inductive reach-scale classification, nested within the segment scale, is based on multivariate statistical clustering of geomorphic data collected at 500-meter intervals along the river. Cluster-based classifications delineate reaches of the river with similar channel and flood-plain geomorphology, and presumably, similar geomorphic and hydrologic processes. The dominant variables in the clustering process were channel width (Fort Randall) and valley width (Sharpe), followed by braiding index (both segments).Clusters with multithread and highly sinuous channels are likely to be associated with dynamic channel migration and deposition of fresh, bare sediment conducive to natural cottonwood germination. However, restoration potential within these reaches is likely to be mitigated by interaction of cottonwood life stages with the highly altered flow regime.

76 FR 8986 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... Main Street, Bloomfield, IN 47424. King County, Washington, and Incorporated Areas Black River... East Valley Road. Springbrook Creek At the upstream side of +19 +10 City of Kent, City of Black River... Assistance No. 97.022, ``Flood Insurance.'') Dated: February 7, 2011. Sandra K. Knight, Deputy Federal...

76 FR 79098 - Final Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-21

... County. Approximately 0.9 mile +3089 downstream of Black Angus Lane. Redwater River Approximately 1,200... Crosse County, Wisconsin, and Incorporated Areas Docket No. FEMA-B-1155 Black River Approximately 0.5... Federal Domestic Assistance No. 97.022, ``Flood Insurance.'') Dated: December 5, 2011. Sandra K. Knight...

24 CFR 200.926d - Construction requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... hazard exposure—(i) Residential structures with basements located in FEMA-designated areas of special flood hazard. The elevation of the lowest floor in structures with basements shall be at or above the... residential structures under regulations for the National Flood Insurance Program (NFIP) (see 44 CFR 60.3...

24 CFR 200.926d - Construction requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... hazard exposure—(i) Residential structures with basements located in FEMA-designated areas of special flood hazard. The elevation of the lowest floor in structures with basements shall be at or above the... residential structures under regulations for the National Flood Insurance Program (NFIP) (see 44 CFR 60.3...

24 CFR 200.926d - Construction requirements.

Code of Federal Regulations, 2011 CFR

2011-04-01

... hazard exposure—(i) Residential structures with basements located in FEMA-designated areas of special flood hazard. The elevation of the lowest floor in structures with basements shall be at or above the... residential structures under regulations for the National Flood Insurance Program (NFIP) (see 44 CFR 60.3...

24 CFR 200.926d - Construction requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... hazard exposure—(i) Residential structures with basements located in FEMA-designated areas of special flood hazard. The elevation of the lowest floor in structures with basements shall be at or above the... residential structures under regulations for the National Flood Insurance Program (NFIP) (see 44 CFR 60.3...

76 FR 39009 - Changes in Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-05

... buildings. The changes in BFEs are in accordance with 44 CFR 65.4. National Environmental Policy Act. This final rule is categorically excluded from the requirements of 44 CFR part 10, Environmental Consideration. An environmental impact assessment has not been prepared. Regulatory Flexibility Act. As flood...

Dual response to nest flooding during monsoon in an Indian ant

PubMed Central

Kolay, Swetashree; Annagiri, Sumana

2015-01-01

Flooding causes destruction of shelter and disruption of activity in animals occupying subterranean nests. To ensure their survival organisms have evolved various responses to combat this problem. In this study we examine the response of an Indian ant, Diacamma indicum, to nest flooding during the monsoon season. Based on characterization of nest location, architecture and the response of these ants to different levels of flooding in their natural habitat as well as in the laboratory, we infer that they exhibit a dual response. On the one hand, the challenges presented by monsoon are dealt with by occupying shallow nests and modifying the entrance with decorations and soil mounds. On the other hand, inundated nests are evacuated and the ants occupy shelters at higher elevations. We conclude that focused studies of the monsoon biology of species that dwell in such climatic conditions may help us appreciate how organisms deal with, and adapt to, extreme seasonal changes. PMID:26349015

Late Pleistocene outburst flooding from pluvial Lake Alvord into the Owyhee River, Oregon

USGS Publications Warehouse

Carter, D.T.; Ely, L.L.; O'Connor, J. E.; Fenton, C.R.

2006-01-01

At least one large, late Pleistocene flood traveled into the Owyhee River as a result of a rise and subsequent outburst from pluvial Lake Alvord in southeastern Oregon. Lake Alvord breached Big Sand Gap in its eastern rim after reaching an elevation of 1292 m, releasing 11.3 km3 of water into the adjacent Coyote Basin as it eroded the Big Sand Gap outlet channel to an elevation of about 1280 m. The outflow filled and then spilled out of Coyote Basin through two outlets at 1278 m and into Crooked Creek drainage, ultimately flowing into the Owyhee and Snake Rivers. Along Crooked Creek, the resulting flood eroded canyons, stripped bedrock surfaces, and deposited numerous boulder bars containing imbricated clasts up to 4.1 m in diameter, some of which are located over 30 m above the present-day channel. Critical depth calculations at Big Sand Gap show that maximum outflow from a 1292- to 1280-m drop in Lake Alvord was ??? 10,000 m3 s- 1. Flooding became confined to a single channel approximately 40 km downstream of Big Sand Gap, where step-backwater calculations show that a much larger peak discharge of 40,000 m3 s- 1 is required to match the highest geologic evidence of the flood in this channel. This inconsistency can be explained by (1) a single 10,000 m3 s- 1 flood that caused at least 13 m of vertical incision in the channel (hence enlarging the channel cross-section); (2) multiple floods of 10,000 m3 s- 1 or less, each producing some incision of the channel; or (3) an earlier flood of 40,000 m3 s- 1 creating the highest flood deposits and crossed drainage divides observed along Crooked Creek drainage, followed by a later 10,000 m3 s- 1 flood associated with the most recent shorelines in Alvord and Coyote Basins. Well-developed shorelines of Lake Alvord at 1280 m and in Coyote Basin at 1278 m suggest that after the initial flood, postflood overflow persisted for an extended period, connecting Alvord and Coyote Basins with the Owyhee River of the Columbia River drainage. Surficial weathering characteristics and planktonic freshwater diatoms in Lake Alvord sediment stratigraphically below Mt. St. Helens set Sg tephra, suggest deep open-basin conditions at ??? 13-14 ka (14C yr) and that the flood and prominent shorelines date to about this time. But geomorphic and sedimentological evidence also show that Alvord and Coyote Basins held older, higher-elevation lakes that may have released earlier floods down Crooked Creek. ?? 2006 Elsevier B.V. All rights reserved.

Application of Multi-Satellite Precipitation Analysis to Floods and Landslides

NASA Technical Reports Server (NTRS)

Adler, Robert; Hong, Yang; Huffman, George

2007-01-01

Satellite data acquired and processed in real time now have the potential to provide the spacetime information on rainfall needed to monitor flood and landslide events around the world. This can be achieved by integrating the satellite-derived forcing data with hydrological models and landslide algorithms. Progress in using the TRMM Multi-satellite Precipitation Analysis (TMPA) as input to flood and landslide forecasts is outlined, with a focus on understanding limitations of the rainfall data and impacts of those limitations on flood/landslide analyses. Case studies of both successes and failures will be shown, as well as comparison with ground comparison data sets both in terms of rainfall and in terms of flood/landslide events. In addition to potential uses in real-time, the nearly ten years of TMPA data allow retrospective running of the models to examine variations in extreme events. The flood determination algorithm consists of four major components: 1) multi-satellite precipitation estimation; 2) characterization of land surface including digital elevation from NASA SRTM (Shuttle Radar Terrain Mission), topography-derived hydrologic parameters such as flow direction, flow accumulation, basin, and river network etc.; 3) a hydrological model to infiltrate rainfall and route overland runoff; and 4) an implementation interface to relay the input data to the models and display the flood inundation results to potential users and decision-makers. In terms of landslides, the satellite rainfall information is combined with a global landslide susceptibility map, derived from a combination of global surface characteristics (digital elevation topography, slope, soil types, soil texture, and land cover classification etc.) using a weighted linear combination approach. In those areas identified as "susceptible" (based on the surface characteristics), landslides are forecast where and when a rainfall intensity/duration threshold is exceeded. Results are described indicating general agreement with landslide occurrences. However, difficulties in comparing landslide event information (mostly from news reports) with the satellite-based forecasts are analyzed.

Floodflow characteristics at proposed bridge site on Fishkill Creek, Fishkill, New York

USGS Publications Warehouse

Zembrzuski, Thomas J.; Dunn, Bernard

1976-01-01

An evaluation of floodflow characteristics of Fishkill Creek at the proposed bridge site at Fishkill, N.Y., was made for the 50- and 100-year floods. The flood-frequency analysis revealed that the magnitude of the 50- and 100-year floods are 8,000 cubic feet per second (cfs) and 10,000 cfs, respectively. The normal water-surface elevation at the approach cross section was determined by the slope-conveyance method to be 209.8 feet during a 50-year flood and 210.8 feet during a 100-year flood. Also included is an analysis of the effect of the existing bridge and of two alternative bridge designs on the profiles of floods having recurrence intervals of 50 and 100 years. (Woodard-USGS)

Wave Height and Water Level Variability on Lakes Michigan and St Clair

DTIC Science & Technology

2012-10-01

Observations: http://www.ssec.wisc.edu/sose/glwx_activity.html 4. NASA Atlas of Extratropical Storm Tracks: http://data.giss.nasa.gov/stormtracks...term meteorological, ice, wave, and water level measurements. 15. SUBJECT TERMS Base flood elevation Coastal flood Extratropical storms Great...Box 1027 Detroit, MI 48231-1027 ERDC/CHL TR-12-23 ii Abstract The Great Lakes are subject to coastal flooding as a result of severe storms

Using Selective Drainage Methods to Extract Continuous Surface Flow from 1-Meter Lidar-Derived Digital Elevation Data

USGS Publications Warehouse

Poppenga, Sandra K.; Worstell, Bruce B.; Stoker, Jason M.; Greenlee, Susan K.

2010-01-01

Digital elevation data commonly are used to extract surface flow features. One source for high-resolution elevation data is light detection and ranging (lidar). Lidar can capture a vast amount of topographic detail because of its fine-scale ability to digitally capture the surface of the earth. Because elevation is a key factor in extracting surface flow features, high-resolution lidar-derived digital elevation models (DEMs) provide the detail needed to consistently integrate hydrography with elevation, land cover, structures, and other geospatial features. The U.S. Geological Survey has developed selective drainage methods to extract continuous surface flow from high-resolution lidar-derived digital elevation data. The lidar-derived continuous surface flow network contains valuable information for water resource management involving flood hazard mapping, flood inundation, and coastal erosion. DEMs used in hydrologic applications typically are processed to remove depressions by filling them. High-resolution DEMs derived from lidar can capture much more detail of the land surface than courser elevation data. Therefore, high-resolution DEMs contain more depressions because of obstructions such as roads, railroads, and other elevated structures. The filling of these depressions can significantly affect the DEM-derived surface flow routing and terrain characteristics in an adverse way. In this report, selective draining methods that modify the elevation surface to drain a depression through an obstruction are presented. If such obstructions are not removed from the elevation data, the filling of depressions to create continuous surface flow can cause the flow to spill over an obstruction in the wrong location. Using this modified elevation surface improves the quality of derived surface flow and retains more of the true surface characteristics by correcting large filled depressions. A reliable flow surface is necessary for deriving a consistently connected drainage network, which is important in understanding surface water movement and developing applications for surface water runoff, flood inundation, and erosion. Improved methods are needed to extract continuous surface flow features from high-resolution elevation data based on lidar.

Erosional and depositional patterns associated with the 1993 Missouri River floods inferred from SIR-C and TOPSAR radar data

USGS Publications Warehouse

Izenberg, N.R.; Arvidson, R. E.; Brackett, R.A.; Saatchi, S.S.; Osburn, G.R.; Dohrenwend, J.

1996-01-01

The Missouri River floods of 1993 caused significant and widespread damage to the floodplains between Kansas City and St. Louis. Immediately downstream of levee breaks, flood waters scoured the bottoms. As the floodwaters continued, they spread laterally and deposited massive amounts of sand as crevasse splays on top of agricultural fields. We explore the use of radar interferometry and backscatter data for quantitative estimation of scour and deposition for Jameson Island/Arrow Rock Bottoms and Lisbon Bottoms, two bottoms that were heavily damaged during the floods and subsequently abandoned. Shuttle imaging radar C (SIR-C) L band (24 cm) HH (horizontally transmitted and horizontally received) radar backscatter data acquired in October 1994 were used together with a distorted Born approximation canopy scattering model to determine that the abundance of natural leafy forbs controlled the magnitude of backscatter for former agricultural fields. Forb areal density was found to be inversely correlated with thickness of sand deposited during the floods, presumably because thick sands prevented roots from reaching nutrient rich, moist bottoms soils. Using the inverse relationship, a lower bound for the mass of sand added was found to be 6.3 million metric tons over the 17 km2 study area. Digital elevation data from topographic synthetic aperture radar (TOPSAR) C band (5.6 cm) interferometric observations acquired in August 1994 were compared to a series of elevation profiles collected on the ground. Vertical errors in TOPSAR were estimated to range from 1 to 2 m, providing enough accuracy to generate an estimate of total mass (4.7 million metric tons) removed during erosion of levees and scour of the bottoms terrains. Net accretion of material to the study areas is consistent with the geologic record of major floods where sediment-laden floodwaters crested over natural levees, initially scoured into the bottoms, and then deposited sands as crevasse splays as the flows spread out and slowed by frictional dissipation. The addition of artificial levees to the Missouri River system has undoubtedly enhanced flood damage, although quantitative estimation of the degree of enhancement will require additional work. Copyright 1996 by the American Geophysical Union.

Erosional and depositional patterns associated with the 1993 Missouri River floods inferred from SIR-C and TOPSAR radar data

NASA Astrophysics Data System (ADS)

Izenberg, N. R.; Arvidson, R. E.; Brackett, R. A.; Saatchi, S. S.; Osburn, G. R.; Dohrenwend, J.

1996-10-01

The Missouri River floods of 1993 caused significant and widespread damage to the floodplains between Kansas City and St. Louis. Immediately downstream of levee breaks, flood waters scoured the bottoms. As the floodwaters continued, they spread laterally and deposited massive amounts of sand as crevasse splays on top of agricultural fields. We explore the use of radar interferometry and backscatter data for quantitative estimation of scour and deposition for Jameson Island/Arrow Rock Bottoms and Lisbon Bottoms, two bottoms that were heavily damaged during the floods and subsequently abandoned. Shuttle imaging radar C (SIR-C) L band (24 cm) HH (horizontally transmitted and horizontally received) radar backscatter data acquired in October 1994 were used together with a distorted Born approximation canopy scattering model to determine that the abundance of natural leafy forbs controlled the magnitude of backscatter for former agricultural fields. Forb areal density was found to be inversely correlated with thickness of sand deposited during the floods, presumably because thick sands prevented roots from reaching nutrient rich, moist bottoms soils. Using the inverse relationship, a lower bound for the mass of sand added was found to be 6.3 million metric tons over the 17 km2 study area. Digital elevation data from topographic synthetic aperture radar (TOPSAR) C band (5.6 cm) interferometric observations acquired in August 1994 were compared to a series of elevation profiles collected on the ground. Vertical errors in TOPSAR were estimated to range from 1 to 2 m, providing enough accuracy to generate an estimate of total mass (4.7 million metric tons) removed during erosion of levees and scour of the bottoms terrains. Net accretion of material to the study areas is consistent with the geologic record of major floods where sediment-laden floodwaters crested over natural levees, initially scoured into the bottoms, and then deposited sands as crevasse splays as the flows spread out and slowed by frictional dissipation. The addition of artificial levees to the Missouri River system has undoubtedly enhanced flood damage, although quantitative estimation of the degree of enhancement will require additional work.

Fifty-year flood-inundation maps for Comayagua, Hondura

USGS Publications Warehouse

Kresch, David L.; Mastin, Mark C.; Olsen, T.D.

2002-01-01

After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of the 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Comayagua that would be inundated by 50-year floods on Rio Humuya and Rio Majada. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Comayagua as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow users to view the flood inundation in much more detail than is possible using the maps in this report. Water-surface elevations for 50-year-floods on Rio Humuya and Rio Majada at Comayagua were estimated using HEC-RAS, a one-dimensional, steady-flow, step-backwater computer program. The channel and floodplain cross sections used in HEC-RAS were developed from an airborne light-detection-and-ranging (LIDAR) topographic survey of the area. The 50-year-flood discharge for Rio Humuya at Comayagua, 1,400 cubic meters per second, was estimated using a regression equation that relates the 50-year-flood discharge to drainage area and mean annual precipitation. The reasonableness of the regression discharge was evaluated by comparing it with drainage-area-adjusted 50-year-flood discharges estimated for three long-term Rio Humuya stream-gaging stations. The drainage-area-adjusted 50-year-flood discharges estimated from the gage records ranged from 946 to 1,365 cubic meters per second. Because the regression equation discharge agrees closely with the high end of the range of discharges estimated from the gaging-station records, it was used for the hydraulic modeling to ensure that the resulting 50-year-flood water-surface elevations would not be underestimated. The 50-year-flood discharge for Rio Majada at Comayagua (230 cubic meters per second) was estimated using the regression equation because there are no long-term gaging-stations on this river from which to estimate the discharge.