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Sample records for phreatic water

  1. Effects of Land Use Change on Phreatic Water Recharge in the Loess Tableland of China

    NASA Astrophysics Data System (ADS)

    Cheng, Liping; Liu, Wenzhao

    2016-04-01

    A long-term located monitoring of soil water, combined with the hydrogen and oxygen stable isotope tracer techniques were used to invedtigated effects of land use change on phreatic water recharge in the Loess Tableland of China. Results showed that piston flow and preferential flow coexisted in the process of phreatic water recharge. The isotopic compositions of groundwater were different from those of deep soil water but similar to those of precipitation, which indicate that preferential flow may be the main groundwater recharge mechanism at present. The yield of cropland has greatly increased and a large area of cropland has been converted to apple orchards since 1980s, which are responsible to the excessively consumed soil water storage in deep soil layers and a decrease of deep percolation of rainwater in different degree. As a result, the phreatic water table has been declining continuously, and a profound change in the natural water cycle and water balance has occurred in the Loess Tableland. The land use structure adjustments need to be guided by policy controls to ensure the renewable capacity and sustainable utilization of phreatic water resources.

  2. Variation of Phreatic Evaporation of Bare Soil and Integration Application in Water Allocation in Shule Basin

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Huang, P.; Gong, G.

    2011-12-01

    Phreatic evaporation is a key element in regional water balance, but it is hardly measured directly. Recently the development of some new technologies brings new dawn to phreatic evaporation measurement, such as eddy covariance, remote sensing ET and so on. But the new technologies have no ability to connect to groundwater yet. Conventional groundwater balance equipment was set up in Shule basin in northwestern China, with located E97°01', N45°13' , altitude 1520m, annual average precipitation 61.8mm and annual evaporation 2600mm (pan 20cm). The experiment field contains 45 lysimeters (65cm diameter). 11 different water table depths are set in the lysimeters, which are 0.5m, 0.75m, 1.0m, 1.25m, 1.5m, 2.0m, 2.5m, 3.0m, 4.0m, 5.0m and 6.0m. The water table in the lysimeter is controlled by Marriott Bottle System. The evaporation and percolation is measured for three different soil types (silt sandy soil, loam soil and clay soil) in the 11 different water table depths. Based on the data from 2006 to 2010, the influences of atmosphere evaporation capacity, phreatic water depth and soil textures are analyzed. Empirical formulae for estimating phreatic evaporation are regressed. The fitting precision of the different formulae are evaluated. The results show that, fitting effect of common empirical formulae is good in Shule river basin. For the different soil types, fitting effect of silt soil is the best, while that of clay soil is relatively low. At last, formulae fitted in other areas and phreatic evaporation tests are summarized. The reasons of difference of fitted coefficients lie in three aspects: the range of depth of groundwater, choice of the value of water evaporation, method to optimize coefficients. Physical meaning of the coefficients in empirical formulae is analyzed. The features, fitting effect and notes in application of formulae are evaluated. The results are applied in water requirement calculation of ecological conservation Dunhuang Xihu Nature

  3. Study on the law of Unsteady Phreatic Water Seepage Near by Canals

    NASA Astrophysics Data System (ADS)

    Cao, P.; Tao, Y.

    2013-12-01

    Unsteady phreatic water seepage nearby canals is a classical problem in seepage mechanics. One of the classic solutions is use Boussinesq equation based on the assumption of Dupuit as the control equation, combine with the boundary conditions and initial conditions to solve it. The method can only used in the case of small hydraulic gradient. The paper take the unsteady phreatic water seepage nearby canals has larger hydraulic gradient as the research object, and establish a model suitable for this condition. Based on the first linearized Boussinesq equation and Laplace transform, the analytical solution of the model is obtained by flow integral and verified by sand tank experiment. The results showed that the free surface nearby canals is "parabolic" form changes to the "asymptotic" form when the canals water level rises. New solution is more realistic and calculate error of the original solution is larger at the beginning of canals water level variation. The law of unsteady phreatic water seepage nearby canals needs further study.

  4. Effect of quality of phreatic aquifer water and water upwelling on constructions. A case study of Ouargla

    NASA Astrophysics Data System (ADS)

    Saggaï, Sofiane; Bachi, Oum Elkheir; Saggaï, Ali

    2016-07-01

    In Ouargla's oasis, which is one of urban conglomerations of Algerian Sahara, the exploitation and/or the overexploitation of the deep aquifers of continental intercalary and of complex terminal that contain waters of mediocre quality (salty and hot), and the rejection of waters of drainage, urban residual waters and non-treated industrial waters are responsible, at the same time, of the degradation of the quality of waters of the groundwater and its upwelling. This situation has led to: (i) the deterioration of the environment and (ii) the deterioration of constructions (houses, roads, etc…). The present paper consists in giving in detail the causes of the water upwelling of phreatic aquifers in our regions, the quality of water of this aquifer and the influence of the quality of phreatic aquifer water on environment and constructions in Ouargla city by analyzing water samples of 10 points of this town.

  5. Detection of the water level in fractured phreatic aquifers using nuclear magnetic resonance (NMR) geophysical measurements

    NASA Astrophysics Data System (ADS)

    Gev, Israel; Goldman, Mark; Rabinovich, Boris; Rabinovich, Michael; Issar, Arie

    1996-06-01

    Correlation of geophysical data collected using the NMR method in the Negev Desert, Israel, with hydrogeological data from nearby observation wells is presented. The experiment was conducted near Kibbutz Revivim in the Besor drainage system (Fig. 1). The objective of the survey was to detect groundwater layers in the Quaternary cover filling and Eocene fractured aquifers down to a depth of 100 m. The experiment was performed using a combination of two different geophysical techniques, namely the NMR and time domain electromagnetic (TDEM) methods. The geophysical results were verified by measuring the water level in three observation wells, two of which were drilled several months after the geophysical survey was carried out. The water level measured in these follow-up observation wells shortly after drilling did not coincide with the geophysical data. However, it settled over a period of time and finally stabilized at a depth very similar to that obtained from the NMR measurements. This phenomenon is caused by the fractured nature of the phreatic aquifer. Since the flow of water in such aquifers is confined by the fractures, the appearance of water in the well during or shortly after drilling is determined solely by the intersection of the well and the fracture. Our experiments showed that geophysical measurements in fractured phreatic aquifers may have a distinct advantage over direct borehole measurements, since the former average the depth to the water table over large areas (several thousand square meters) while the latter are limited by the area of the borehole cross-section (several tens of square centimeters).

  6. Evolution of isolated caves in porous limestone by mixing of phreatic water and surface water at the water table of unconfined aquifers: A model approach

    NASA Astrophysics Data System (ADS)

    Dreybrodt, W.; Romanov, D.; Kaufmann, G.

    2009-09-01

    SummaryWhen water from the surface, e.g. from a lake flows through porous carbonate rocks down along some region with high hydraulic conductivity and encounters the water table of a phreatic aquifer both waters mix by diffusion along their boundary. In a carbonate aquifer, where both surface and phreatic waters are saturated with respect to calcite, mixing corrosion causes renewed dissolution of the carbonate rock in the diffusional mixing zone extending from the boundary separating the phreatic water from the surface water encountering it. A numerical model is presented from which the initial change of porosity in such a diffusional mixing zone is obtained. The initial change of porosity dΦ/ dt/0 is proportional to |∇→m(x, y)|2 and d2Δ c eq( m)/ dm2. m( x, y) is the spatial distribution of the mixing ratio, m = V sur/( V sur + V phr), and the Vs assign the corresponding volumes of surface and phreatic water. d2Δ c eq/ dm2 is the second derivative of Δ c eq, the renewed dissolution capacity of the mixed solution. It has been calculated for three geochemical scenarios with differing CO 2 concentrations of surface and phreatic water by use of PHREEQC-2. The spatial distribution m( x, y) is obtained by using MODFLOW and MT3DMS in a modeling domain with constant hydraulic conductivity for various flow velocities of the phreatic aquifer. From the results the time scale of cave evolution is estimated. Passages of dimensions of about one meter in width and several 10 cm in height, extending in length along the border line, where surface and phreatic water meet, can be created in time scales of 10 000 years. These caves are horizontal with blind ending passages and resemble closely to the isolated caves observed in Central West Florida. For more realistic modeling we have used a geostatistical local distribution of hydraulic conductivities in the modeling domain. For a correlation length of 1% of the length of modeling domain the spatial distribution extends deeper

  7. Anthropogenic contamination of a phreatic drinking water winning: 3-dimensional reactive transport modelling

    NASA Astrophysics Data System (ADS)

    Griffioen, J.; van der Grift, B.; Maas, D.; van den Brink, C.; Zaadnoordijk, J. W.

    2003-04-01

    Groundwater is contaminated at the regional scale by agricultural activities and atmospheric deposition. A 3-D transport model was set-up for a phreatic drinking water winning, where the groundwater composition was monitored accurately. The winning is situated at an area with unconsolidated Pleistocene deposits. The land use is nature and agriculture. Annual mass-balances were determined using a wide range of historic data. The modelling approach for the unsaturated zone was either simple box models (Cl, NO_3 and SO_4) or 1-D transport modelling using HYDRUS (Cd). The modelling approach for the saturated zone used a multiple solute version of MT3D, where denitrification associated with pyrite oxidation and sorption of Cd were included. The solute transport calculations were performed for the period 1950--2030. The results obtained for the year 2000 were used as input concentration for the period 2000--2030. A comparison between the calculated and the measured concentrations of groundwater abstracted for Cl, NO_3 and SO_4 yields the following. First, the input at the surface is rather well estimated. Second, the redox reactivity of the first two aquifers is negligible around the winning, which is confirmed by respiration experiments using anaerobically sampled aquifer sediments. The reactivity of the third aquifer, which is a marine deposit and lies at least 30 meters below surface, is considerable. The discrepancies between modelled and measured output are explained by lack of knowledge about the subsurface reactivity and/or wrong estimates of surface loading and leaching from the unsaturated zone. The patterns for other hydrogeochemical variables such as Ca, HCO_3 may further constrain this lack of knowledge. The results for Cd indicate that Cd becomes strongly retarded, despite the low reactivity of the sandy sediments. The winning is rather insensitive to Cd contamination (but the surface water drainage network is not). Two major uncertainties for input of Cd

  8. A new analytical approach to estimate the hydraulic parameters of a coastal phreatic aquifer from tidally induced water table fluctuations and its application at the Niijima Island, Japan

    NASA Astrophysics Data System (ADS)

    Aichi, M.; Shiokari, M.; Tokunaga, T.

    2010-12-01

    A new perturbation solution of the Boussinesq equation for tidally induced water table fluctuations in a coastal phreatic aquifer was derived under the condition of multiple tidal constituents. Then, the obtained solution was applied to estimate hydraulic parameters of the Shiro-mama formation at the Niijima Island, Japan, by fitting the solution to the results of continuous measurements of water table fluctuations in the frequency space. The estimated hydraulic transmissivities from both the amplitudes and the phase-shifts were comparable and consistent with the results of analyses based on the Dupuit-Ghyben-Herzberg model, suggesting that the proposed approach performed well and the obtained values, i.e., transmissivity to be 0.12-1.7 m2/s were reasonable.

  9. Phreatic and Hydrothermal Explosions: A Laboratory Approach

    NASA Astrophysics Data System (ADS)

    Scheu, B.; Dingwell, D. B.

    2010-12-01

    Phreatic eruptions are amongst the most common eruption types on earth. They might be precursory to another type of volcanic eruption but often they stand on their one. Despite being the most common eruption type, they also are one of the most diverse eruptions, in appearance as well as on eruption mechanism. Yet steam is the common fuel behind all phreatic eruptions. The steam-driven explosions occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or fresh volcanic deposits (such as ignimbrites, tephra and pyroclastic-flow deposits) and result in crater, tuff rings and debris avalanches. The intense heat of such material may cause water to boil and flash to steam, thereby generating an explosion of steam, water, ash, blocks, and bombs. Another wide and important field affected by phreatic explosions are hydrothermal areas; here phreatic explosions occur every few months creating explosion craters and resemble a significant hazard to hydrothermal power plants. Despite of their hazard potential, phreatic explosions have so far been overlooked by the field of experimental volcanology. A part of their hazard potential in owned by the fact that phreatic explosions are hardly predictable in occurrence time and size as they have manifold triggers (variances in groundwater and heat systems, earthquakes, material fatigue, water level, etc..) A new set of experiments has been designed to focus on this phreatic type of steam explosion, whereas classical phreatomagmatic experiments use molten fuel-coolant interaction (e.g., Zimanowski, et al., 1991). The violent transition of the superheated water to vapour adds another degree of explosivity to the dry magmatic fragmentation, driven mostly by vesicle bursting due to internal gas overpressure. At low water fractions the fragmentation is strongly enforced by the mixture of these two effects and a large fraction of fine pyroclasts are produced, whereas at high water fraction in the sample the

  10. Steady state phreatic surfaces in sloping aquifers

    NASA Astrophysics Data System (ADS)

    LoáIciga, Hugo A.

    2005-08-01

    Steady state groundwater flow driven by constant recharge in an unconfined aquifer overlying sloping bedrock is shown to be represented, using the Dupuit approximation, by an ordinary differential equation of the Abel type y(x) · y'(x) + a · y(x) + x = 0, whose analytical solution is derived in this work. This article first investigates the case of zero saturated thickness at the upstream boundary, a flow system reminiscent of perched groundwater created by percolation of precipitation or irrigation in a sloping aquifer fully draining at its downstream boundary. A variant of this flow system occurs when the phreatic surface mounds and produces groundwater discharge toward the upstream boundary. This variant is a generalization of the classical groundwater flow problem involving two lakes connected by an aquifer, the latter being on sloping terrain in this instance. Analytical solutions for the phreatic surface's steady state geometry are derived for the case of monotonically declining hydraulic head as well as for the case of a mounded phreatic surface. These solutions are of practical interest in drainage studies, slope stability, and runoff formation investigations. It is shown that the flow factor a = -? tan β (where K, N, and tan β are the hydraulic conductivity, vertical recharge, and aquifer slope, respectively) has a commanding role on the phreatic surface's solutions. Two computational examples illustrate the implementation of this article's results.

  11. Steady state phreatic surfaces in sloping aquifers

    NASA Astrophysics Data System (ADS)

    Loáiciga, Hugo A.

    2005-08-01

    Steady state groundwater flow driven by constant recharge in an unconfined aquifer overlying sloping bedrock is shown to be represented, using the Dupuit approximation, by an ordinary differential equation of the Abel type y(x) . y'(x) + a . y(x) + x = 0, whose analytical solution is derived in this work. This article first investigates the case of zero saturated thickness at the upstream boundary, a flow system reminiscent of perched groundwater created by percolation of precipitation or irrigation in a sloping aquifer fully draining at its downstream boundary. A variant of this flow system occurs when the phreatic surface mounds and produces groundwater discharge toward the upstream boundary. This variant is a generalization of the classical groundwater flow problem involving two lakes connected by an aquifer, the latter being on sloping terrain in this instance. Analytical solutions for the phreatic surface's steady state geometry are derived for the case of monotonically declining hydraulic head as well as for the case of a mounded phreatic surface. These solutions are of practical interest in drainage studies, slope stability, and runoff formation investigations. It is shown that the flow factor a = -$\\sqrt{{\\rm K}/{\\rm N} tan β (where K, N, and tan β are the hydraulic conductivity, vertical recharge, and aquifer slope, respectively) has a commanding role on the phreatic surface's solutions. Two computational examples illustrate the implementation of this article's results.

  12. Hydrothermal alteration favoring phreatic eruption processes at Solfatara (Campi Flegrei)

    NASA Astrophysics Data System (ADS)

    Mayer, Klaus; Scheu, Bettina; Montanaro, Cristian; Aßbichler, Donjá; Isaia, Roberto; Dingwell, Donald B.

    2015-04-01

    Solfatara and Pisciarelli fumaroles are the main surface manifestations of the strong hydrothermal activity within the Campi Flegrei caldera system and pointing to a significant risk for phreatic eruptions in this densely populated area. Phreatic eruptions, triggered by various processes are hardly predictable in occurrence time and size. Despite their hazard potential, these eruptions, as well as the influence of hydrothermal alteration on their likelihood, magnitude and style, have so far been largely overlooked in experimental volcanology. The physical properties and the mechanical behavior of volcanic rocks are highly dependent on their original magmatic microstructure and on any eventual alteration of those microstructures due to hydrothermal reactions. We have therefore investigated the potential effects of hydrothermal alteration on rock microstructure and, as a consequence, on fragmentation dynamics. Rock samples from the vicinity of the Solfatara and Pisciarelli fumaroles have been characterized 1) geochemically (X-ray fluorescence, X-ray diffraction), 2) physically (density, porosity, permeability and elastic wave velocity) and 3) mechanically (uniaxial compressive strength, tensile strength). We furthermore have investigated the effects of hydrothermal alteration on fragmentation processes using a shock-tube apparatus, operating with Argon gas, water vapor and superheated water at temperatures up to 400°C and maximum pressures of 20 MPa. Fragmentation and ejection dynamics in the presence of three different energy sources within the pores have been investigated: overpressure by 1) Argon gas; or 2) water vapor and due to 3) steam flashing of superheated water. Fragmentation speed, fragmentation efficiency and fragmented particle ejection velocity were measured. Our results indicate on the one hand, that steam flashing provides the highest energy - resulting in increased fragmentation speed and particle ejection velocity and also a significant higher

  13. Effects of water extraction in a vulnerable phreatic aquifer: Consequences for groundwater contamination by pesticides, Sint-Jansteen area, The Netherlands

    NASA Astrophysics Data System (ADS)

    Gaus, Irina

    Pesticides are a potential threat to the quality of extracted groundwater when the water-supply area is used for agricultural activities. This problem is discussed for the water-supply area of Sint-Jansteen, The Netherlands, where measured pesticide concentrations in the extracted water regularly exceed EU limits (0.1μg/L). Groundwater samples taken from the aquifer within the water-supply area show low contamination, but samples taken from the extracted water occasionally contain pesticides, making the water inadequate for drinking-water purposes. The more intense contamination of the extracted water is caused by the change in the natural groundwater flow pattern near the extraction wells. In this area, pesticide use cannot be avoided easily, and an approach is given to differentiate pesticide use in the area according to expected travel time toward the wells and the chemical characteristics of the pesticides. A groundwater flow model for the area is developed and the effects of groundwater extraction on the natural flow pattern are evaluated. Using particle tracking, the travel-time zones are determined. Combining these results and the degradation behavior of certain pesticides led to an optimal scheme to integrate agricultural activities and groundwater extraction in the area. This is illustrated for five different types of pesticides (atrazine, simazine, bentazone, MCPA, and mecoprop). Résumé Les pesticides sont une menace potentielle pour la qualité de l'eau souterraine prélevée lorsque la zone de captage est soumise à des activités agricoles. Ce problème est discuté dans le cas de la zone de captage de Sint-Jansteen (Pays-Bas), où les concentrations mesurées en pesticides dans les eaux pompées dépassent régulièrement les normes européennes (0,1μg/L). Les échantillons d'eau souterraine prélevés dans l'aquifère dans la zone de captage montrent une faible contamination, mais les échantillons d'eau pompée contiennent occasionnellement des

  14. Effects of water extraction in a vulnerable phreatic aquifer: Consequences for groundwater contamination by pesticides, Sint-Jansteen area, The Netherlands

    NASA Astrophysics Data System (ADS)

    Gaus, Irina

    Pesticides are a potential threat to the quality of extracted groundwater when the water-supply area is used for agricultural activities. This problem is discussed for the water-supply area of Sint-Jansteen, The Netherlands, where measured pesticide concentrations in the extracted water regularly exceed EU limits (0.1μg/L). Groundwater samples taken from the aquifer within the water-supply area show low contamination, but samples taken from the extracted water occasionally contain pesticides, making the water inadequate for drinking-water purposes. The more intense contamination of the extracted water is caused by the change in the natural groundwater flow pattern near the extraction wells. In this area, pesticide use cannot be avoided easily, and an approach is given to differentiate pesticide use in the area according to expected travel time toward the wells and the chemical characteristics of the pesticides. A groundwater flow model for the area is developed and the effects of groundwater extraction on the natural flow pattern are evaluated. Using particle tracking, the travel-time zones are determined. Combining these results and the degradation behavior of certain pesticides led to an optimal scheme to integrate agricultural activities and groundwater extraction in the area. This is illustrated for five different types of pesticides (atrazine, simazine, bentazone, MCPA, and mecoprop). Résumé Les pesticides sont une menace potentielle pour la qualité de l'eau souterraine prélevée lorsque la zone de captage est soumise à des activités agricoles. Ce problème est discuté dans le cas de la zone de captage de Sint-Jansteen (Pays-Bas), où les concentrations mesurées en pesticides dans les eaux pompées dépassent régulièrement les normes européennes (0,1μg/L). Les échantillons d'eau souterraine prélevés dans l'aquifère dans la zone de captage montrent une faible contamination, mais les échantillons d'eau pompée contiennent occasionnellement des

  15. Recurrent patterns in fluid geochemistry data prior to phreatic eruptions

    NASA Astrophysics Data System (ADS)

    Rouwet, Dmitri; Sandri, Laura; Todesco, Micol; Tonini, Roberto; Pecoraino, Giovannella; Diliberto, Iole Serena

    2016-04-01

    Not all volcanic eruptions are magma-driven: the sudden evaporation and expansion of heated groundwater may cause phreatic eruptions, where the magma involvement is absent or negligible. Active crater lakes top some of the volcanoes prone to phreatic activity. This kind of eruption may occur suddenly, and without clear warning: on September 27, 2014 a phreatic eruption of Ontake, Japan, occurred without timely precursors, killing 57 tourists near the volcano summit. Phreatic eruptions can thus be as fatal as higher VEI events, due to the lack of recognised precursory signals, and because of their explosive and violent nature. In this study, we tackle the challenge of recognising precursors to phreatic eruptions, by analysing the records of two "phreatically" active volcanoes in Costa Rica, i.e. Poás and Turrialba, respectively with and without a crater lake. These volcanoes cover a wide range of time scales in eruptive behaviour, possibly culminating into magmatic activity, and have a long-term multi-parameter dataset mostly describing fluid geochemistry. Such dataset is suitable for being analysed by objective pattern recognition techniques, in search for recurrent schemes. The aim is to verify the existence and nature of potential precursory patterns, which will improve our understanding of phreatic events, and allow the assessment of the associated hazard at other volcanoes, such as Campi Flegrei or Vulcano, in Italy. Quantitative forecast of phreatic activity will be performed with BET_UNREST, a Bayesian Event Tree tool recently developed within the framework of FP7 EU VUELCO project. The study will combine the analysis of fluid geochemistry data with pattern recognition and phreatic eruption forecast on medium and short-term. The study will also provide interesting hints on the features that promote or hinder phreatic activity in volcanoes that host well-developed hydrothermal circulation.

  16. An analytical model for predicting transport in a coupled vadose/phreatic system

    SciTech Connect

    Tomasko, D.

    1997-05-01

    A simple analytical model is presented for predicting the transport of a contaminant in both the unsaturated (vadose) and saturated (phreatic) zones following a surficial spill. The model incorporates advection, dispersion, adsorption, and first-order decay in both zones and couples the transport processes at the water table. The governing equation is solved by using the method of Laplace transforms, with numerical inversion of the Laplace space equation for concentration. Because of the complexity of the functional form for the Laplace space solution, a numerical methodology using the real and imaginary parts of a Fourier series was implemented. To reduce conservatism in the model, dilution at the water table was also included. Verification of the model is demonstrated by its ability to reproduce the source history at the surface and to replicate appropriate one-dimensional transport through either the vadose or phreatic zone. Because of its simplicity and lack of detailed input data requirements, the model is recommended for scoping calculations.

  17. Geomicrobiology of Phreatic Caves Associated With Central Florida Springs

    NASA Astrophysics Data System (ADS)

    Giannotti, A. L.; Tysall, T. N.; Franklin, R. B.; Mills, A. L.

    2005-05-01

    Phreatic (underwater) limestone caves are common in Florida in association with the numerous springs that issue from the karst landscape. Extensive microbial mats and diverse communities of invertebrates have been observed by cave divers, but, as ecosystems, the caves are not well studied. Four aphotic aquatic caves were identified in which to investigate relationships between microbial communities and their geochemical surroundings, and to evaluate the potential for chemolithoautotrophic microbial activity to support higher-order consumers. The caves were associated with the discharge sites of four different second-magnitude springs (flow: 0.3 to 3 m3 s-1) in central Florida in which communities containing microbial mats, isopods, amphiphods, and cave crayfish have been observed. Samples of bulk water and microbial mat were collected along the flow path in each cave; depths ranged from 0.5 to 15 m below the ground surface, and penetration distance extended up to 250 m from each cave entrance. Microscopic examination of the mats revealed the presence of sulfur-granule-containing, filamentous morphologies consistent with Thiothrix and Beggiatoa and an unidentified filamentous iron bacteria. The bacteria were found in all four springs, but H2S was detected in water samples from only one of the caves. In many cases, the morphology of the organisms changed along the flow path within an individual spring, although there was little change in the associated water chemistry (pH, dissolved oxygen, conductivity, total Fe, NH4+, NO3-, HS-, SO42-, PO4-, Cl-, Fl-, Ca2+, Na+, and Mg2+). The overall water chemistry of the four caves/springs was distinct (principal components analysis), and the major differences were due to Ca2+, K+, and Cl- concentrations, pH (range: 7.3 to 8.4), and sulfur and iron availability. Efforts to culture the dominant organisms in each set of mats (using media prepared with cave or spring water) and community-level genetic analyses (T-RFLP) demonstrated

  18. Strip-focused phreatic surface flow driven by evaporation: Analytical solution by the Riesenkampf function

    NASA Astrophysics Data System (ADS)

    Kacimov, A. R.; Obnosov, Yu. V.

    2006-10-01

    Steady free-surface seepage in a homogeneous porous aquifer is studied by a conformal mapping of the inversed hodograph (angle) onto the domain in the Riesenkampf plane (slanted-face half-strip or trapezium). Seepage from the water table is caused by evaporation uniformly distributed with a horizontal coordinate. This distributed sink forms a regional trough on the phreatic surface with groundwater moving from the flanks to the trough center on the regional scale and from the water table to the soil surface locally. The free surfaces, streamlines of marked particles, travel times, and Darcian velocity are presented.

  19. Influence of hydrothermal alteration on phreatic eruption processes in Solfatara (Campi Flegrei)

    NASA Astrophysics Data System (ADS)

    Mayer, K.; Scheu, B.; Montanaro, C.; Isaia, R.; Dingwell, D. B.

    2014-12-01

    The strong hydrothermal activity exhibited at Campi Flegrei by the Solfatara and Pisciarelli fumaroles points to a significant risk for phreatic eruptions in this densely populated area. Phreatic eruptions, triggered by various processes are hardly predictable in occurrence time and size. Despite their hazard potential, these eruptions, as well as the influence of hydrothermal alteration on their likelihood, magnitude and style, have so far been largely overlooked in experimental volcanology. The physical properties and the mechanical behavior of volcanic rocks are highly dependent on their original magmatic microstructure and on any eventual alteration of those microstructures due to hydrothermal reactions. We have therefore investigated the potential effects of hydrothermal alteration on rock microstructure and, as a consequence, on fragmentation dynamics. Rock samples from the vicinity of the Solfatara fumaroles have been characterized 1) geochemically (X-ray fluorescence, X-ray diffraction), 2) physically (density, porosity, permeability and elastic wave velocity) and 3) mechanically (uniaxial compressive strength, tensile strength). We have investigated the effects of hydrothermal alteration on fragmentation processes using a shock-tube apparatus, operating with Argon gas, water vapor and superheated water at temperatures up to 400°C and maximum pressures of 20 MPa. The three different energy sources within the pores initiating fragmentation, have been investigated: overpressure by 1) Argon gas; or 2) water vapor and due to 3) steam flashing of water. Fragmentation speed, fragmentation efficiency and fragmented particle ejection velocity were measured. Our results indicate, that steam flashing provides the highest energy - resulting in increased particle ejection velocity and higher fragmentation efficiency. Based on our results, we aim to constrain the influence of hydrothermal alteration on the dynamics of phreatic explosions and the effect on the amount of

  20. Short-period volcanic gas precursors to phreatic eruptions: Insights from Poás Volcano, Costa Rica

    USGS Publications Warehouse

    de Moor, Maarten; Aiuppa, Alessandro; Pacheco, Javier; Avard, Geoffroy; Kern, Christoph; Liuzzo, Marco; Martinez, Maria; Giudice, Gaetano; Fischer, Tobias P.

    2016-01-01

    Volcanic eruptions involving interaction with water are amongst the most violent and unpredictable geologic phenomena on Earth. Phreatic eruptions are exceptionally difficult to forecast by traditional geophysical techniques. Here we report on short-term precursory variations in gas emissions related to phreatic blasts at Poás volcano, Costa Rica, as measured with an in situ multiple gas analyzer that was deployed at the edge of the erupting lake. Gas emitted from this hyper-acid crater lake approaches magmatic values of SO2/CO2 1–6 days prior to eruption. The SO2 flux derived from magmatic degassing through the lake is measureable by differential optical absorption spectrometry (sporadic campaign measurements), which allows us to constrain lake gas output and input for the major gas species during eruptive and non-eruptive periods. We can further calculate power supply to the hydrothermal system using volatile mass balance and thermodynamics, which indicates that the magmatic heat flux into the shallow hydrothermal system increases from ∼27 MW during quiescence to ∼59 MW during periods of phreatic events. These transient pulses of gas and heat from the deeper magmatic system generate both phreatic eruptions and the observed short-term changes in gas composition, because at high gas flux scrubbing of sulfur by the hydrothermal system is both kinetically and thermodynamically inhibited whereas CO2gas is always essentially inert in hyperacid conditions. Thus, the SO2/CO2 of lake emissions approaches magmatic values as gas and power supply to the sub-limnic hydrothermal system increase, vaporizing fluids and priming the hydrothermal system for eruption. Our results suggest that high-frequency real-time gas monitoring could provide useful short-term eruptive precursors at volcanoes prone to phreatic explosions.

  1. Recharge characteristics of a phreatic aquifer as determined by storage accumulation

    NASA Astrophysics Data System (ADS)

    Ketchum, Neil J.; Donovan, Joseph J.; Avery, William H.

    2000-12-01

    The cumulative storage accumulation curve (CSAC) is a tool for saturated-volume fluctuation (SVF) analysis of transient recharge to shallow phreatic aquifers discharging only to springs. The method assumes that little underflow or phreatic evapotranspiration occurs. The CSAC is a modified water-table hydrograph that distinguishes storage increase caused by recharge from loss due to springflow-induced recession. Required for the analysis are water-table fluctuations at a single representative location within the catchment of a single spring and either direct measurements or robust interpolations of springflows at different aquifer stages. The method employs empirical manipulation of head observations, varying spring catchment area to minimize CSAC water-level changes in late portions of long recessions. Results include volumetric estimates of recharge integrated over individual events and instantaneous rates of recharge to the water table, at the temporal resolution of the water-level sampling interval. The analysis may also yield physically realistic information on spring catchment and recharge focusing. In a test case in West Virginia, USA, recharge estimates by this technique were consistent with integrated springflow time series but greater than estimates based on potential evapotranspiration. Results give insight into dynamic recharge behavior over time as well as an indication of recharge catchment size.

  2. Sources of the nitrate in phreatic groundwater in the western Kalahari

    NASA Astrophysics Data System (ADS)

    Heaton, T. H. E.

    1984-01-01

    Elevated levels of nitrate occur in phreatic groundwater in the western Kalahari, Namibia. Nitrate in water containing 0.4-3.1 meq NO -3l -1, of widespread occurrence, has δ 15N values in the range +4.9 to +8.0‰, suggesting natural derivation from the soil. The sporadic occurrence of very high levels of nitrate (> 4 meq NO -3l -1), which has δ 15N between +9.3 to +18.7‰, reflects pollution derived from animal waste. The importance of considering the possible isotopic effects of denitrification, and the significance of leaching in the nitrogen budget of the Kalahari soil, are also discussed.

  3. Determination of heterogeneities in the hydraulic properties of a phreatic aquifer from tidal level fluctuations: a case in Argentina

    NASA Astrophysics Data System (ADS)

    Carol, Eleonora S.; Kruse, Eduardo E.; Pousa, Jorge L.; Roig, Alejandro R.

    2009-11-01

    A well-known analytical solution of Jacob (1950) for groundwater flow due to tidal-wave propagation, together with field measurements along a complete tidal cycle and geological data, were used to evaluate the heterogeneities in the hydraulic properties of a phreatic aquifer located next to the River Ajo in the coastal plain environment of the southern sector of the Samborombon Bay wetland, Argentina. From the analysis of water-table fluctuations in a set of monitoring wells located along a riverbank-normal transect, it was possible to quantify the piecewise spatial variations of the hydraulic diffusivity of the phreatic aquifer. The results show the strong lateral variations of the sedimentary environment due to the influence of the different transport and deposition agents that characterize the coastal plain. The known thickness of the phreatic aquifer and the estimated range of the specific yield allowed the hydraulic conductivity to be identified as the most influential factor. [Jacob CE (1950) Flow of ground water. In: Rouse H (ed) Engineering Hydraulics. Wiley, New York

  4. Computation of average seasonal groundwater flows in phreatic aquifer-river system

    NASA Astrophysics Data System (ADS)

    Rastogi, A. K.

    1991-03-01

    A simplified approach to reduce a time-variant problem into a steady-state problem is considered by averaging the groundwater head over a seasonal period. This averaging is applicable to those areas (countries) where a year can be divided into three distinct monsoon, pre- and post-monsoon periods and where the annual watertable variation is not large compared with the saturated aquifer thickness. This scheme is applied to solve a two-dimensional problem using a standard finite difference technique of solution. The phreatic aquifer system considered is bounded by two reservoirs and an impervious base. It also contains a partially penetrating river near the centre of the aquifer. Periodic contribution to the phreatic aquifer from the higher head reservoir, groundwater recharge from river seepage, net-free surface flux and the total groundwater flow towards lower head reservoir are worked out. These terms aid in estimating the net volume of ground water that is available from the aquifer system in a particular seasonal period.

  5. Novel Microbial Diversity Retrieved by Autonomous Robotic Exploration of the World's Deepest Vertical Phreatic Sinkhole

    NASA Astrophysics Data System (ADS)

    Sahl, Jason W.; Fairfield, Nathaniel; Harris, J. Kirk; Wettergreen, David; Stone, William C.; Spear, John R.

    2010-03-01

    The deep phreatic thermal explorer (DEPTHX) is an autonomous underwater vehicle designed to navigate an unexplored environment, generate high-resolution three-dimensional (3-D) maps, collect biological samples based on an autonomous sampling decision, and return to its origin. In the spring of 2007, DEPTHX was deployed in Zacatón, a deep (˜318 m), limestone, phreatic sinkhole (cenote) in northeastern Mexico. As DEPTHX descended, it generated a 3-D map based on the processing of range data from 54 onboard sonars. The vehicle collected water column samples and wall biomat samples throughout the depth profile of the cenote. Post-expedition sample analysis via comparative analysis of 16S rRNA gene sequences revealed a wealth of microbial diversity. Traditional Sanger gene sequencing combined with a barcoded-amplicon pyrosequencing approach revealed novel, phylum-level lineages from the domains Bacteria and Archaea; in addition, several novel subphylum lineages were also identified. Overall, DEPTHX successfully navigated and mapped Zacatón, and collected biological samples based on an autonomous decision, which revealed novel microbial diversity in a previously unexplored environment.

  6. Novel microbial diversity retrieved by autonomous robotic exploration of the world's deepest vertical phreatic sinkhole.

    PubMed

    Sahl, Jason W; Fairfield, Nathaniel; Harris, J Kirk; Wettergreen, David; Stone, William C; Spear, John R

    2010-03-01

    The deep phreatic thermal explorer (DEPTHX) is an autonomous underwater vehicle designed to navigate an unexplored environment, generate high-resolution three-dimensional (3-D) maps, collect biological samples based on an autonomous sampling decision, and return to its origin. In the spring of 2007, DEPTHX was deployed in Zacatón, a deep (approximately 318 m), limestone, phreatic sinkhole (cenote) in northeastern Mexico. As DEPTHX descended, it generated a 3-D map based on the processing of range data from 54 onboard sonars. The vehicle collected water column samples and wall biomat samples throughout the depth profile of the cenote. Post-expedition sample analysis via comparative analysis of 16S rRNA gene sequences revealed a wealth of microbial diversity. Traditional Sanger gene sequencing combined with a barcoded-amplicon pyrosequencing approach revealed novel, phylum-level lineages from the domains Bacteria and Archaea; in addition, several novel subphylum lineages were also identified. Overall, DEPTHX successfully navigated and mapped Zacatón, and collected biological samples based on an autonomous decision, which revealed novel microbial diversity in a previously unexplored environment. PMID:20298146

  7. The yearly amount and characteristics of deep-buried phreatic evaporation in hyper-arid areas

    NASA Astrophysics Data System (ADS)

    Li, H.; Wang, W.; Zhan, H.; Qiu, F.; Wu, F.; Zhang, G.

    2015-12-01

    Water scarcity is the primary cause of land deterioration, so finding new available water resources is crucial to ecological restoration. We investigated a hyper-arid Gobi location in the Dunhuang Mogao Grottoes in this work wherein the burial depth of phreatic water is over 200 m. An air-conditioner was used in a closed greenhouse to condense and measure the yearly amount of phreatic evaporation (PE) from 2010 to 2015. The results show that the annual quantity of PE is 4.52 mm, and that the PE has sinusoidal characteristics. The average PE is 0.0183 mm d-1 from March to November. Accordingly, by monitoring the annual changes in soil-air temperature and humidity to a depth of 5.0 m, we analyzed the water migration mechanism in the heterothermozone (subsurface zone of variable temperature). The results show that, from March to November, the temperature and absolute humidity (AH) increase. This is due to the flow of solar heat entering the soil - the soil subsequently releases moisture and the soil is in a state of increasing AH so that evaporation occurs. From November to March, the temperature decreases. Now, the soil absorbs water vapor and AH is in a state of decline. Thus, it is temperature alternation in the heterothermozone - due to solar heat transfer - that provides the main driving power for PE. When it drives water vapor to move downwards in the heterothermozone, a small part is reversed upwards and evaporates. Solar radiation intensity dominates the annual sinusoidal PE characteristics.

  8. Estimating phreatic evaporation in irrigated areas using a stable isotope approach

    NASA Astrophysics Data System (ADS)

    Barthold, F. K.; Umirzakov, G.; Schneider, K.; Stulina, G.; Frede, H.; Breuer, L.

    2011-12-01

    Central Asia is characterized by continental arid climate conditions. Mean annual precipitation is 170 mm with a potential evapotranspiration rate of 1200 mm/a. In addition, many regions are affected by a non-sustainable use of the water resources. 90% of the water resources are used for irrigation purposes to grow e.g. cotton and wheat, especially in Uzbekistan. Large amounts of water are needed for cotton growth. Not only does the plant itself require large amounts of water but a substantial part of the water use is ascribed to the inefficient irrigation system and management. The irrigation infrastructure is old and not maintained well and irrigation management is inadequate. Groundwater level rise has been observed in irrigated areas as a result of the inefficient irrigation practices. Capillary raised groundwater is particularly prone to evaporation as it gets closer to the soil surface. The general objective of this study is to quantify the amount of groundwater (or phreatic) evaporation that is due to groundwater table rise on irrigated fields. In this study, we present an approach where we are using stable isotopes of water to estimate phreatic evaporation on irrigated fields. Our specific objective is to estimate phreatic evaporation (Ep) in relation to the groundwater level and varying soil types (sandy, loamy and clay loamy). We chose a stable water isotopes approach to estimate Ep. For this purpose, soil samples along a depth profile were sampled on sites with different groundwater levels and soil types. Samples were taken in 10 cm increments down to the groundwater level. Soil water was extracted using a cryogenic vacuum distillation and the extracted soil water was analyzed for its composition of stable water isotopes, δD and δ18O, using a Liquid Water Isotope Analyzer (Los Gatos Research, Inc.). Ep was calculated by fitting an exponential function to the experimental isotope soil profile. Our results show that in sandy and loamy soils, enrichment

  9. Determining vertical leakage from the Great Artesian Basin, Australia, through up-scaling field estimates of phreatic evapotranspiration

    NASA Astrophysics Data System (ADS)

    Costelloe, J. F.; Matic, V.; Western, A. W.; Walker, J. P.; Tyler, M.

    2015-10-01

    Understanding the water balance of large groundwater systems is fundamental for the sustainable management of the resource. The vertical leakage (i.e. discharge to upper aquifers or the unconfined water table) component of the Great Artesian Basin (GAB) is an example of a poorly constrained but large component of the water balance of Australia's largest groundwater resource. Field estimates of phreatic evapotranspiration (ET) were made at discharge zones along the southwestern margin of the GAB using eddy covariance station and micro-lysimeter measurements, and inversion of chloride/isotope soil profile measurements. The field estimates were assigned to three major landforms associated with areas of increasingly higher evaporative discharge and progressively decreasing depths to the water table. These landforms were mapped using remote sensing and digital elevation data, with characteristically higher soil moisture, salt precipitation, and lower surface temperature compared to areas distal to discharge zones. Based on the field measurements, broad ranges of phreatic ET (0.5-10, 10-100 and 100-300 mm y-1) were assigned to the major land-types. The higher phreatic ET discharge zones mapped by supervised classification of satellite data are 8-28% of the total regional vertical leakage component estimated by numerical modelling of the GAB. In comparison, the higher discharge zones estimated by landform mapping are 73-251% of the total vertical leakage component estimated by modelling. The mapped distribution of the high discharge areas has important implications for modelling of the GAB. In the western sub-basin, most of the estimated recharge can be accounted for by phreatic ET in the high discharge zones located around the Basin margins, implying that vertical leakage rates distal to the margins are very low and that discharge may exceed current recharge. In contrast, the results for the eastern sub-basin suggest that vertical leakage rates around the South

  10. A simple model of a phreatic surface through an earth dam

    USGS Publications Warehouse

    Hromadka, T.V., II

    1984-01-01

    A simple numerical model for estimating a phreatic surface in an earthen dam is presented. The numerical approach is based upon the Complex Variable Boundary Element Method (CVBEM). By expanding the CVBEM approximation geometric functions into a first order Taylor series, the unknown phreatic surface location geometrics can be approximated without iteration by solving a single matrix system. The developed technique provides for the numerical solution of the inverse problem of locating the phreatic surface coordinates. A comparison of results produced from this simple approach to results produced from a finite element analog and an iterative CVBEM analog for an example problem is presented. ?? 1984.

  11. Dissolved gases in hydrothermal (phreatic) and geyser eruptions at Yellowstone National Park, USA

    USGS Publications Warehouse

    Hurwitz, Shaul; Clor, Laura; McCleskey, R. Blaine; Nordstrom, D Kirk; Hunt, Andrew G.; Evans, William C.

    2016-01-01

    Multiphase and multicomponent fluid flow in the shallow continental crust plays a significant role in a variety of processes over a broad range of temperatures and pressures. The presence of dissolved gases in aqueous fluids reduces the liquid stability field toward lower temperatures and enhances the explosivity potential with respect to pure water. Therefore, in areas where magma is actively degassing into a hydrothermal system, gas-rich aqueous fluids can exert a major control on geothermal energy production, can be propellants in hazardous hydrothermal (phreatic) eruptions, and can modulate the dynamics of geyser eruptions. We collected pressurized samples of thermal water that preserved dissolved gases in conjunction with precise temperature measurements with depth in research well Y-7 (maximum depth of 70.1 m; casing to 31 m) and five thermal pools (maximum depth of 11.3 m) in the Upper Geyser Basin of Yellowstone National Park, USA. Based on the dissolved gas concentrations, we demonstrate that CO2 mainly derived from magma and N2 from air-saturated meteoric water reduce the near-surface saturation temperature, consistent with some previous observations in geyser conduits. Thermodynamic calculations suggest that the dissolved CO2 and N2 modulate the dynamics of geyser eruptions and are likely triggers of hydrothermal eruptions when recharged into shallow reservoirs at high concentrations. Therefore, monitoring changes in gas emission rate and composition in areas with neutral and alkaline chlorine thermal features could provide important information on the natural resources (geysers) and hazards (eruptions) in these areas.

  12. Mud plumbing system of an isolated phreatic eruption at Akita Yakeyama volcano, northern Honshu, Japan

    NASA Astrophysics Data System (ADS)

    Ohba, T.; Taniguchi, H.; Miyamoto, T.; Hayashi, S.; Hasenaka, T.

    2007-03-01

    A small phreatic eruption occurred on 16 August 1997 at the flank of a dacite lava dome of Akita Yakeyama, northern Honshu, Japan. Air-falls and viscous mudflows were discharged from two craters. Mudflow effusion preceded discrete explosions, followed by a fine ash discharge. The air-fall deposit consists of an upper fine ash deposit and a lower ballistic-dominated, poorly sorted tephra in which ranges in grain size from fine ash to blocks of ca. 50 cm. Both air fall and mudflow deposits were composed of fine mud and coarse lithic fragments, which contained abundant liquid water. Lithic fragments comprise fresh dacite of the host lava dome and hydrothermally altered stratocone andesite. Intensely altered andesite fragments contain quartz, cristobalite, andalusite, pyrophyllite, 7 Å-kaolin, and anhydrite. Some mineral assemblages indicate hydrothermal temperatures greater than 300 °C. Rare sandstone fragments are likely to be lacustrine from ca. 1000 m depth. The surface morphology of the mudflow deposits indicates that the mud contained ca. 30 vol.% water. The cube-root similarity rules on crater size and the cloud shape of buried explosions provided energy of 3-5 × 10 9 J at depths of 6-10 m, based on the observed crater size (20 m) and fountain-like cloud shape. The depth estimate is consistent with the abundance of coarse dacite fragments derived from shallow lava in the explosion deposit. Thermodynamic energy release of ca. 1 × 10 11 J was calculated based on the following estimated parameters: product volume of 1 × 10 3 m 3, hydrothermal temperatures of 300-350 °C, and pressures of 11-24 MPa corresponding to the estimated source depth. The thermodynamic estimation represents the total energy released during the eruption, whereas the similarity rule yields an energy value as created by discrete explosions. Mud ascended from a hot aquifer at 1000 m depth, first effused as a mudflow, and was then expelled explosively from another crater. Explosivity depends

  13. Field experiments and numerical simulations of phreatic aquifer response to pond infiltration at the eastern Alps foothills, Italy

    NASA Astrophysics Data System (ADS)

    Teatini, Pietro; Comerlati, Andrea; Paiero, Giovanni; Martelli, Grazia; Carvalho, Tiago; Guetz, Anna; Fanzutti, Francesco; Affatato, Alessandro; Baradello, Luca; Nieto, Daniel; Bongiovanni, Stefano; Mattassi, Giorgio; Botti, Fabio

    2014-05-01

    A large volume of surficial fresh high-quality water flows every year from the eastern Alps foothills into the northern Adriatic sea through a number of rivers (e.g., the Tagliamento, Isonzo, Livenza rivers). Crossing a highly permeable plain just south of the Alpine range, the rivers naturally recharge along their course a thick phreatic aquifer mainly composed by gravel and fractured conglomerates. The river waters are distributed across the territory through a dense channel network used for irrigation during the hot season. From autumn to spring this water could be used to recharge the aquifer through a number of large infiltration ponds excavated in the early 2000s, but never used because of legislative limitation. Within the WARBO LIFE+ project, the Environmental Agency of the region has allowed to use the Mereto infiltration basin for recharging the aquifer, after detailed test for surficial water quality and compatibility with the groundwater. The pond is about 6 m deep and 45×7 m2 wide. The site, which is characterized by an elevation of 105 m above msl and a 50 m depth to the phreatic water table, has been accurately characterized by geophysical (geoelectrical, georadar, seismic) surveys and a number of 70 m deep boreholes drilled in the basin surroundings. The permeability evaluated through pumping tests in these boreholes is on the order of 10-4 m/s. Recharge started in December 2013 with an infiltration on the order of 720 m3/day. The collected data, i.e. the water volume flowed into the pond, its water level, and the piezometric evolution in the wellbores around the basin have been used for the calibration of a finite element three-dimensional variably-saturated flow model. The calibrated model will be used to manage the full-scale recharge project in the future.

  14. A Study of the King's Bowl Phreatic Explosion Crater as an Analog to Pits on Solar System Exploration Target Bodies

    NASA Astrophysics Data System (ADS)

    Sears, D. W. G.; Hughes, S. S.; Kobs-Nawotniak, S. E.; Borg, C.; Kim, K. J.; Sears, H.; Skok, J. R.; Elphic, R. C.; Lim, D. S. S.; Heldmann, J. L.; Haberle, C. W.; Guy, H.; Kobayashi, L.; Garry, B.; Neish, C.

    2014-12-01

    The phreatic explosion crater King's Bowl (KB), at Craters of the Moon, Idaho, can serve as an analog to pits with similar morphologies on the Moon, Mars, and Vesta. These pits are associated with the release of water and are of interest to the planetary science and astrobiology research communities. KB crater was formed 2,220 ± 100 B.P. when a magmatic dike encountered subsurface water. The resulting explosion created an 85 m long, 30 m wide and 30 m deep crater and ejected blocks distances in excess of 100 m. Here we describe fieldwork and observations performed by the NASA SSERVI FINESSE (Field Investigations to Enable Solar System Science) team. Our objective is to utilize the distribution of ejecta blocks at King's Bowl to better understand the formation energetics associated with such pits and to quantify the amount of water necessary to produce them on other planetary bodies. We focused on the western KB ejecta field, and ran a westerly line, a line N45oW, and a line S45oW. Along these transects, we photographed and recorded the location, size and mass (when <18 kg) of every block > 20 cm. We collected photographs normal to the surface, every 10 m, to determine block number density. Thirdly, we walked in a raster pattern through the field cataloging blocks >20 cm. Finally, we mapped the perimeter of the crater. Initial results suggest similarities between KB ejecta distributions and ejecta of impact craters on Earth, asteroids, Phobos, Deimos, and the Moon. These similarities are; the radial extent of the ejecta, the decrease in number density with distance, the aspect ratio of the blocks, proximity of the largest blocks to the rim, and the size of the largest blocks relative to the crater diameter. This implies a similar physics of formation on differing bodies whether derived through impact or phreatic explosion. Further studies at KB crater will provide insight to the formation of phreatic explosion pits on other planetary bodies, most especially the

  15. Experimental constraints on phreatic eruption processes at Whakaari (White Island volcano)

    NASA Astrophysics Data System (ADS)

    Mayer, Klaus; Scheu, Bettina; Gilg, H. Albert; Heap, Michael J.; Kennedy, Ben M.; Lavallée, Yan; Letham-Brake, Mark; Dingwell, Donald B.

    2015-09-01

    Vigorous hydrothermal activity interspersed by sequences of phreatic and phreatomagmatic eruptions occur at Whakaari (White Island volcano), New Zealand. Here, we investigate the influence of sample type (hydrothermally altered cemented ash tuffs and unconsolidated ash/lapilli) and fragmentation mechanism (steam flashing versus gas expansion) on fragmentation and ejection velocities as well as on particle-size and shape. Our rapid decompression experiments show that fragmentation and ejection speeds of two ash tuffs, cemented by alunite and amorphous opal, increase with increasing porosity and that both are significantly enhanced in the presence of steam flashing. Ejection speeds of unconsolidated samples are higher than ejection speeds of cemented tuffs, as less energy is consumed by fragmentation. Fragmentation dominated by steam flashing results in increased fragmentation energy and a higher proportion of fine particles. Particle shape analyses before and after fragmentation reveal that both steam flashing and pure gas expansion produce platy or bladed particles from fracturing parallel to the decompression front. Neither fragmentation mechanisms nor sample type show a significant influence on the shape. Our results emphasize that, under identical pressure and temperature conditions, eruptions accompanied by the process of liquid water flashing to steam are significantly more violent than those driven simply by gas expansion. Therefore, phase changes during decompression and cementation are both important considerations for hazard assessment and modeling of eruptions in hydrothermally active environments.

  16. Phreatomagmatic and phreatic fall and surge deposits from explosions at Kilauea volcano, Hawaii, 1790 a.d.: Keanakakoi Ash Member

    USGS Publications Warehouse

    McPhie, J.; Walker, G.P.L.; Christiansen, R.L.

    1990-01-01

    progressive degassing and cooling of the magma during deep withdrawal: throughout the phreatomagmatic phases magma vesiculation contributed to the explosive interaction with water by initiating the fragmentation process: thereafter, the principal role of the subsiding magma column was to supply heat for steam production that drove the phreatic explosions of the final phase. ?? 1990 Springer-Verlag.

  17. Assessment of hydraulic parameters in the phreatic aquifer of Settolo (Italy): a stochastic approach

    NASA Astrophysics Data System (ADS)

    Salandin, P.; Zovi, F.; Camporese, M.

    2012-12-01

    In this work we present and test against real field data an inversion approach for the identification of hydraulic parameters at the aquifer scale. Our test field is the alluvial phreatic aquifer of Settolo, located along the left bank of the Piave River in a piedmont area in Northeastern Italy, with an extension of approximately 6 km2 and exhibiting heterogeneities of the geological structures both at the local and intermediate scales. The area is characterized by the alluvial sediments (mainly gravel in a sandy matrix) deposited by the Piave River during the Last Glacial Maximum, being the subsurface, with an average aquifer thickness of 50 m, crossed by paleo-riverbeds that probably represent the main hydrogeological unit from which water is withdrawn. The interactions between watercourses and the aquifer, the recharge linked to the precipitation, as well as the dynamics of partially penetrating extraction wells must be properly reproduced for an effective protection and a sustainable exploitation of the water resources. In order to do so, in cooperation with Alto Trevigiano Servizi S.r.l., the local water resources management company, a careful site characterization is in progress since 2009, with a number of different measurements and scales involved. Besides surface ERT, water quality surveys, and a tracer test, we highlight here the role of 18 continuously monitored observation wells, available in the study area for the measurement of the water table dynamics and the calibration/validation of groundwater models. A preliminary comparison with the results of a three-dimensional Richards model demonstrated that the site can be properly described by means of a two-dimensional finite element solver of the nonlinear Dupuit-Boussinesq equation, saving CPU time and computer storage. Starting from an ensemble of randomly generated and spatially correlated hydraulic conductivity (K) fields, the fit between water table observations and model predictions is measured

  18. Phreatic activity on Dominica (Lesser Antilles) - constraints from field investigations and experimental volcanology

    NASA Astrophysics Data System (ADS)

    Mayer, K.; Scheu, B.; Rott, S.; Dingwell, D. B.; Gilg, H. A.

    2015-12-01

    Dominica has one of the highest concentrations of potentially active volcanoes worldwide. In addition to this activity, abundant geothermal manifestations are observed at the surface, especially in the southern part of the Island. The Boiling Lake - Valley of Desolation area is one of the most vigorous ones, hosting hot springs, mud pools, fumaroles, and steam vents. Intense alteration and many, predominantly phreatic explosive features, of varying scales characterize the whole area. The most prominent manifestation of such a phreatic eruption is the Boiling Lake, a high temperature volcanic crater lake and popular tourist attraction. Thus phreatic activity is one of the main volcanic hazards on the Island, to date largely unpredictable in time and magnitude. The conditions causing these eruptions, as well as their trigger mechanisms and magnitude need to be better understood. Field mapping, together with the determination of in situ physical (density, humidity, permeability) and mechanical (strength, stiffness) properties yield the characterization of 3 main active areas with high probabilities for phreatic events. Rapid decompression experiments on samples from these areas gave insights into the fragmentation and ejection behavior. These experiments were flanked by chemical analyses and laboratory characterization (porosity, granulometry). The results show that hydrothermal alteration likely plays a crucial role in determining the probability of explosive events. High temperature acidic fluids, which lead to an intense alteration of the host rock's mineralogy, change the rock properties favoring the formation of a low permeability layer above the vent and increasing the likelihood of the site experiencing a steam-blast eruption. The contribution of these results to constraining the conditions for and the dynamics involved in phreatic eruptions provides valuable input to hazard assessment of these frequently visited sites on Dominica and similar hydrothermally

  19. Seismic signature of a phreatic explosion: hydrofracturing damage at Karthala volcano, Grande Comore Island, Indian Ocean

    NASA Astrophysics Data System (ADS)

    Savin, Cécile; Grasso, Jean-Robert; Bachelery, Patrick

    2005-09-01

    Karthala volcano is a basaltic shield volcano with an active hydrothermal system that forms the southern two-thirds of the Grande Comore Island, off the east coat of Africa, northwest of Madagascar. Since the start of volcano monitoring by the local volcano observatory in 1988, the July 11th, 1991 phreatic eruption was the first volcanic event seismically recorded on this volcano, and a rare example of a monitored basaltic shield. From 1991 to 1995 the VT locations, 0.5phreatic eruption is a typical pattern of the seismicity induced by controlled fluid injections such as those applied at geothermal fields, in oil and gas recovery, or for stress measurements. It suggests the 1991 phreatic eruption was driven by hydraulic fracturing induced by forced fluid flow. We propose that the extremely high LP and VT seismicity rates, relative to other effusive volcanoes, during the climax of the 1991 phreatic explosion, are due to the activation of the whole hydrothermal system, as roughly sized by the distribution of VT hypocenters. The seismicity rate in 1995 was still higher than the pre-eruption seismicity rate, and disagrees with the time pattern of thermo-elastic stress readjustment induced by single magma intrusions at basaltic volcanoes. We propose that it corresponds to the still ongoing relaxation of pressure heterogeneity within the hydrothermal system as suggested by the few LP events that still occurred in 1995.

  20. Seismic signature of a phreatic explosion: Hydrofracturing damage at Karthala volcano, Grande Comore Island, Indian Ocean

    USGS Publications Warehouse

    Savin, C.; Grasso, J.-R.; Bachelery, P.

    2005-01-01

    Karthala volcano is a basaltic shield volcano with an active hydrothermal system that forms the southern two-thirds of the Grande Comore Island, off the east coat of Africa, northwest of Madagascar. Since the start of volcano monitoring by the local volcano observatory in 1988, the July 11th, 1991 phreatic eruption was the first volcanic event seismically recorded on this volcano, and a rare example of a monitored basaltic shield. From 1991 to 1995 the VT locations, 0.5phreatic eruption is a typical pattern of the seismicity induced by controlled fluid injections such as those applied at geothermal fields, in oil and gas recovery, or for stress measurements. It suggests the 1991 phreatic eruption was driven by hydraulic fracturing induced by forced fluid flow. We propose that the extremely high LP and VT seismicity rates, relative to other effusive volcanoes, during the climax of the 1991 phreatic explosion, are due to the activation of the whole hydrothermal system, as roughly sized by the distribution of VT hypocenters. The seismicity rate in 1995 was still higher than the pre-eruption seismicity rate, and disagrees with the time pattern of thermo-elastic stress readjustment induced by single magma intrusions at basaltic volcanoes. We propose that it corresponds to the still ongoing relaxation of pressure heterogeneity within the hydrothermal system as suggested by the few LP events that still occurred in 1995. ?? Springer-Verlag 2005.

  1. Hydrothermal processes at Milos Island (Greek Cyclades) and the mechanisms of compaction-induced phreatic eruptions

    NASA Astrophysics Data System (ADS)

    Fontaine, F. Jh.; Rabinowicz, M.; Boulègue, J.

    2003-05-01

    steam pockets can trigger phreatic eruptions that form the 15-20-m-large, 3-4-m-deep craters. When the fluid is water-like, the overpressures are too small to generate an eruption. The fluids percolate through the quartz aggregate, leading to the formation of 2-3-m-wide, 0.5-1-m-deep, bowl-like cavities. This model is consistent with field observations at Milos.

  2. DRASTIC-GIS model for assessing vulnerability to pollution of the phreatic aquiferous formations in Douala-Cameroon

    NASA Astrophysics Data System (ADS)

    Victorine Neh, Akenji; Ako Ako, Andrew; Richard Ayuk, Akoachere; Hosono, Takahiro

    2015-02-01

    The pollution potentials of the aquiferous formations in Douala was obtained by evaluating the aquifer vulnerability. Aquifer vulnerability is an intrinsic property of groundwater which gives the possibility of percolation and diffusion of contaminants from the ground surface into the subsurface. Aquifer vulnerability to pollution was evaluated for the phreatic aquifer in Douala using the DRASTIC method. DRASTIC is a groundwater quality model representing; Depth to Water, Net Recharge, Aquifer Media, Soil Media, Topography, Impact of vadose Zones, and Hydraulic Conductivity. From data, five thematic maps were generated and an intrinsic vulnerability map was developed based upon calculations of DRASTIC Indices (D.I). The D.I for the different inhabited quarters were; Bonamoussadi (BS) = 145, Bali (BA) = 138, Bonapriso (BP) = 140, Airport(AP) = 129, Ndogbong(ND) = 120, Bepanda(BE) = 130, Vallee Besengue (VB) = 134, New Bell (NB) = 125, Bonassama BM) = 128 and Rail(RA) = 167. ArcGIS quantile classification subdivided the area into four groups; very low, low, moderate and high ground water vulnerability risk zones covering about 30%, 30%, 20% and 20% of the study area respectively. An in-depth study is recommended to give a detailed perspective to the evolution and nature of actual pollution in the area.

  3. Hydrogeochemical characterization of the phreatic system of the coastal wetland located between Fiumi Uniti and Bevano rivers in the southern Po plain (Northern Italy).

    NASA Astrophysics Data System (ADS)

    Marconi, V.; Dinelli, E.; Antonellini, M.; Capaccioni, B.; Balugani, E.; Gabbianelli, G.

    2009-04-01

    A hydrogeochemical study has been undertaken on the phreatic system of the coastal area included between Fiumi Uniti and Bevano rivers (in the southern part of the Po plain, near the city of Ravenna) within the framework of the CIRCLE-ERANET project WATERKNOW on the effects of climate change on the mediterranean catchments. It is one of the first attempt in the area to characterize the shallow groundwater water system and to investigate if the arsenic anomaly, known in deeper groundwater (about 100 µg/l according to recent Annual Groundwater Quality Reports of Emilia-Romagna Region), occurs also in the phreatic system. The coastal part of the Po plain consists of a low-lying and mechanically-drained farmland further from the sea and of a narrow belt of dunes and pine forests in the backshore area. The study area is recognized as a protected area at european (ZPS and SIC, site code number: IT 14070009), national and regional level (Po delta Park area). As a result of an intensive exploitation of coastal aquifers for agricultural, industrial, and civil uses, both the phreatic aquifer and the surface waters (drainage ditches and ponds) have been contaminated by seawater and by deeper groundwater. Samples representative of the top of the water table were collected in Summer 2008 in 22 auger-holes and in 3 shallow piezometers (6 m deep) documenting the deeper layers of the phreatic groundwater system. Temperature, electrical conductivity, pH and Eh of the groundwater and of the surface water were measured on site using portable instruments. Samples were filtered directly in the field, an aliquot was acidified with diluted HCl for metal analysis. Cations were determined by Flame Atomic Absorption (thermo S-series spectrometer), anions by ion chromatography (Dionex ICS-90), Fe, As, Si, B by ICP-OES (Thermo iCAP6000). The data collected in the field show that a fresh groundwater lens is still present at the top of the phreatic aquifer in the backshore area and that the

  4. Analysis of phreatic events at Ruapehu volcano, New Zealand using a new SOM approach

    NASA Astrophysics Data System (ADS)

    Carniel, Roberto; Jolly, Arthur D.; Barbui, Luca

    2013-03-01

    We apply Self-Organising Maps (SOM) to assess the low level seismic activity prior to small scale phreatic events at Ruapehu volcano New Zealand. The SOM approach allows an automatic pattern recognition, virtually independent from a priori knowledge. Volcanic tremor spectra are randomly presented to the network in a competitive iterative training process, followed by a hierarchical clusterization of the SOM nodes. Spectra are then projected, ordered by time, to clusters on the map. A coherent time evolution of the data through the clusters can highlight the existence of different regimes and the transitions between them. Two Ruapehu events were examined: a phreatic event on 4 October 2006 which displaced the crater lake producing a 4 m high wave on the lake edge, and the more energetic 25 September 2007 phreatic eruption. The SOM analysis provides a classification of tremor spectral patterns that clusters into three regimes that we label by colours. The pattern for both eruptions is consistent with a pre-eruption spectral pattern including enhanced spectral energy in the range of 4 to 6 Hz — labelled 'green tremor'. This gives way to spectra having broader energy between 2 and 6 Hz, the so called 'red tremor' just prior to the eruption. The post eruption pattern includes spectral peaks at generally lower frequencies of 2 to 4 Hz — the so called 'blue tremor'. Clusterization into only three groups yields highly non-unique solutions which cannot explain the variety of processes operating at Ruapehu over long time periods. Regardless, the approach highlights noteworthy similarities that may be explained by a pattern of slow pressurisation under a hydrothermal or magmatic seal - 'green' - followed by seal failure - 'red' - and subsequent de-pressurisation - 'blue' - for the two events studied. Although the application shown here is limited, we think it demonstrates the power of this classification approach.

  5. An observation-based model for a vapor-driven crack growth leading up to the phreatic eruption of Mt. Ontake in 2014

    NASA Astrophysics Data System (ADS)

    Maeda, Y.; Kato, A.; Terakawa, T.; Yamanaka, Y.; Horikawa, S.; Matsuhiro, K.; Okuda, T.

    2015-12-01

    At Mt. Ontake, central Japan, a phreatic eruption took place on 27 September 2014. The eruption was preceded for 25 s by a very long period (VLP) seismic event and for 450 s by an accelerated tilt change showing summit uplift. To deepen our understanding of the initiation of the phreatic eruption, we conducted waveform inversion and time series analyses of these preceding events. Our waveform inversion of the VLP event pointed to an SSE-NNW strike subvertical tensile crack at around 600 m beneath the eruptive vent region. This crack orientation was subparallel to alignments of volcano-tectonic earthquake hypocenters (Kato et al., 2015) and eruptive vents (Geospatial Information Authority of Japan, 2014) as well as one of the maximum shear directions of the regional stress field (Terakawa et al., 2015). These observations suggest that the VLP source crack was one of the preexisting faults along the maximum shear direction that opened due to passage of ascending gas from depth to the surface. Our waveform inversion of the tilt change pointed to an E-W to SE-NW strike subvertical tensile crack at around 1000 m below the surface. To investigate a background physics of the tilt change, we calculated the first and second order integrals of the tilt waveforms (I1(t) and I2(t), respectively, where t is time). The ratio I2(t)/I1(t) initially increased linearly with time and then reached an almost constant value. This time evolution is well modeled by a linear increase of the source crack volume V(t)=V0t/t0 (tt0), where V0 is constant, τ≈84 s, and t0/τ≈2. The initial linear growth of the crack volume may be explained by inflation of water vapor in the vertical crack under constant pressure and heat supply conditions. The latter exponential crack growth may be modeled by a force balance between an overpressure of 104-105 Pa and a viscous resistance of the water vapor near the crack tip (Lister and Kerr

  6. Preparatory and precursory processes leading up to the 2014 phreatic eruption of Mount Ontake, Japan

    NASA Astrophysics Data System (ADS)

    Kato, Aitaro; Terakawa, Toshiko; Yamanaka, Yoshiko; Maeda, Yuta; Horikawa, Shinichiro; Matsuhiro, Kenjiro; Okuda, Takashi

    2015-07-01

    We analyzed seismicity linked to the 2014 phreatic eruption of Mount Ontake, Japan, on 27 September 2014. We first relocated shallow volcano tectonic (VT) earthquakes and long-period (LP) events from August to September 2014. By applying a matched-filter technique to continuous waveforms using these relocated earthquakes, we detected numerous additional micro-earthquakes beneath the craters. The relocated VT earthquakes aligned on a near-vertical plane oriented NNW-SSE, suggesting they occurred around a conduit related to the intrusion of magmatic-hydrothermal fluids into the craters. The frequency of VT earthquakes gradually increased from 6 September 2014 and reached a peak on 11 September 2014. After the peak, seismicity levels remained elevated until the eruption. b-values gradually increased from 1.2 to 1.7 from 11 to 16 September 2014 then declined gradually and dropped to 0.8 just before the eruption. During the 10-min period immediately preceding the phreatic eruption, VT earthquakes migrated in the up-dip direction as well as laterally along the NNW-SSE feature. The migrating seismicity coincided with an accelerated increase of pre-eruptive tremor amplitude and with an anomalous tiltmeter signal that indicated summit upheaval. Therefore, the migrating seismicity suggests that the vertical conduit was filled with pressurized fluids, which rapidly propagated to the surface during the final 10 min before the eruption.

  7. Reconstruction of a phreatic eruption on 27 September 2014 at Ontake volcano, central Japan, based on proximal pyroclastic density current and fallout deposits

    NASA Astrophysics Data System (ADS)

    Maeno, Fukashi; Nakada, Setsuya; Oikawa, Teruki; Yoshimoto, Mitsuhiro; Komori, Jiro; Ishizuka, Yoshihiro; Takeshita, Yoshihiro; Shimano, Taketo; Kaneko, Takayuki; Nagai, Masashi

    2016-05-01

    The phreatic eruption at Ontake volcano on 27 September 2014, which caused the worst volcanic disaster in the past half-century in Japan, was reconstructed based on observations of the proximal pyroclastic density current (PDC) and fallout deposits. Witness observations were also used to clarify the eruption process. The deposits are divided into three major depositional units (Units A, B, and C) which are characterized by massive, extremely poorly sorted, and multimodal grain-size distribution with 30-50 wt% of fine ash (silt-clay component). The depositional condition was initially dry but eventually changed to wet. Unit A originated from gravity-driven turbulent PDCs in the relatively dry, vent-opening phase. Unit B was then produced mainly by fallout from a vigorous moist plume during vent development. Unit C was derived from wet ash fall in the declining stage. Ballistic ejecta continuously occurred during vent opening and development. As observed in the finest population of the grain-size distribution, aggregate particles were formed throughout the eruption, and the effect of water in the plume on the aggregation increased with time and distance. Based on the deposit thickness, duration, and grain-size data, and by applying a scaling analysis using a depth-averaged model of turbulent gravity currents, the particle concentration and initial flow speed of the PDC at the summit area were estimated as 2 × 10-4-2 × 10-3 and 24-28 m/s, respectively. The tephra thinning trend in the proximal area shows a steeper slope than in similar-sized magmatic eruptions, indicating a large tephra volume deposited over a short distance owing to the wet dispersal conditions. The Ontake eruption provided an opportunity to examine the deposits from a phreatic eruption with a complex eruption sequence that reflects the effect of external water on the eruption dynamics.

  8. Phreatic activity in the Valley of Desolation, Dominica (Lesser Antilles) - constraints from field investigations and experimental volcanology

    NASA Astrophysics Data System (ADS)

    Mayer, Klaus; Scheu, Bettina; Montanaro, Cristian; Yilmaz, Tim; Aßbichler, Donja; Gilg, H. Albert; Dingwell, Donald B.

    2016-04-01

    Dominica has one of the highest concentrations of potentially active volcanoes worldwide, flanked by abundant surficial geothermal manifestations: The Boiling Lake - Valley of Desolation area represents one of the most vigorous ones, hosting hot springs, mud pools, fumaroles, and steam vents. Intense alteration, together with predominantly phreatic explosive features of varying scales, characterize the whole area. The last historic eruptions in Dominica occurred at the Valley of Desolation. Phreatic eruptions are also the most likely type of volcanic activity to occur in the near future at Dominica in general and the Valley of Desolation in particular. Phreatic eruptions are up to date largely unpredictable in time and magnitude, strongly asking for constraints of eruptive conditions as well as trigger mechanisms. We conducted sampling and field mapping, together with the determination of in situ physical (density, humidity, permeability) and mechanical (strength, stiffness) properties to characterize the main active surficial area which possesses a high probability for a phreatic event. Rapid decompression experiments performed on selected samples from this area give insight into the fragmentation and ejection behavior of steam driven eruptions. These experiments were flanked by chemical analyses and laboratory measurements as porosity and granulometry. The results indicate that advanced argillic alteration in the proximity of degassing vents significantly changes the rock properties, which in turn play a crucial role for the degassing of hydrothermal systems. High-temperature acidic fluids lead to an intense alteration of the host rocks, and thereby cause the formation of a kaolinite-rich, low permeable layer above the vent. In addition, alteration enhances slope instabilities causing landslides which may cover and clog the outgassing vents. Such processes increase the likelihood of the site experiencing a pressurization, which may result in a steam

  9. Estimation of total discharged mass from the phreatic eruption of Ontake Volcano, central Japan, on September 27, 2014

    NASA Astrophysics Data System (ADS)

    Takarada, Shinji; Oikawa, Teruki; Furukawa, Ryuta; Hoshizumi, Hideo; Itoh, Jun'ichi; Geshi, Nobuo; Miyagi, Isoji

    2016-08-01

    The total mass discharged by the phreatic eruption of Ontake Volcano, central Japan, on September 27, 2014, was estimated using several methods. The estimated discharged mass was 1.2 × 106 t (segment integration method), 8.9 × 105 t (Pyle's exponential method), and varied from 8.6 × 103 to 2.5 × 106 t (Hayakawa's single isopach method). The segment integration and Pyle's exponential methods gave similar values. The single isopach method, however, gave a wide range of results depending on which contour was used. Therefore, the total discharged mass of the 2014 eruption is estimated at between 8.9 × 105 and 1.2 × 106 t. More than 90 % of the total mass accumulated within the proximal area. This shows how important it is to include a proximal area field survey for the total mass estimation of phreatic eruptions. A detailed isopleth mass distribution map was prepared covering as far as 85 km from the source. The main ash-fall dispersal was ENE in the proximal and medial areas and E in the distal area. The secondary distribution lobes also extended to the S and NW proximally, reflecting the effects of elutriation ash and surge deposits from pyroclastic density currents during the phreatic eruption. The total discharged mass of the 1979 phreatic eruption was also calculated for comparison. The resulting volume of 1.9 × 106 t (using the segment integration method) indicates that it was about 1.6-2.1 times larger than the 2014 eruption. The estimated average discharged mass flux rate of the 2014 eruption was 1.7 × 108 kg/h and for the 1979 eruption was 1.0 × 108 kg/h. One of the possible reasons for the higher flux rate of the 2014 eruption is the occurrence of pyroclastic density currents at the summit area.

  10. Shallow pressure sources associated with the 2007 and 2014 phreatic eruptions of Mt. Ontake, Japan

    NASA Astrophysics Data System (ADS)

    Takagi, Akimichi; Onizawa, Shin'ya

    2016-07-01

    We modeled pressure sources under Mount Ontake volcano, Japan, on the basis of global navigation satellite system (GNSS) observations of ground deformation during the time period including the 2007 and 2014 phreatic eruptions. The total change in volume in two sources below sea level in the period including the 2007 eruption was estimated from GNSS network observations to be 6 × 106 m3. Additionally, data from a GNSS campaign survey yielded an estimated volume change of 0.28 × 106 m3 in a shallower source just beneath the volcanic vents. The 2007 eruption may have been activated by magmatic activity at depth. During the 2014 eruption, the volume change at depth was very small. However, tiltmeter data indicated inflation from a shallow source that began 7 min before the eruption, representing a volume change estimated to be 0.38 × 106 m3. We infer that the potential for subsurface hydrothermal activity may have remained high after the 2007 eruption.

  11. Structure and stratigraphy beneath a young phreatic vent: South Inyo Crater, Long Valley caldera, California

    SciTech Connect

    Eichelberger, J.C.; Vogel, T.A.; Younker, L.W.; Dan Miller, C.; Heiken, G.H.; Wohletz, K.H.

    1988-11-10

    An 861-m-long hole has been cored on a slanted trajectory that passed directly beneath South Inyo Crater in the west moat of Long valley Caldera, California. The purpose of the hole was to investigate the magmatic behavior that led to surface deformation and phreatic activity during the 600-year-old eruption of the Inyo vent chain. The hole was sited 216 m southwest of the crater, passed beneath its center at a depth of 566 m, and terminated 79 m northeast of the crater center at a depth of 810 m. Metamorphic basement was encountered at a depth of 779 m. The volcanic and sedimentary sequence consists solely of post-Bishop Tuff caldera fill, including 319 m of moat basalt and 342 m of early rhyolite, and is nearly 900 m thinner than in a Unocal Corporation well 900 m to the southeast. Apparently, a major fault lies between the two holes and forms part of the western structural boundary of the caldera, 3--4 km inboard of its topographic boundary. Breccia zones that intrude the caldera fill were intersected at 12.0--9.3 m and 1.2--0.8 m SW and 8.5--25.1 m NE of the crater center.

  12. Precursory tilt changes of small phreatic eruptions of Meakan-dake volcano, Hokkaido, Japan, in November 2008

    NASA Astrophysics Data System (ADS)

    Aoyama, Hiroshi; Oshima, Hiromitsu

    2015-07-01

    Although forecasting an occurrence of phreatic eruption is very difficult, it has been reported that some precursory activities often precede these eruptions at several volcanoes. In this study, we observed seismic activities before and during the 2008 phreatic eruption at Meakan-dake volcano, eastern Hokkaido, Japan, by using broadband seismometers and surface mount-type tiltmeters. The precursory increase in seismicity began in late September about 2 months before the first eruption on November 18. After several rises and falls in seismicity in October and in early November, a small volcanic tremor was observed early on November 16. Although the original velocity seismogram of the tremor generally appeared to be spindle shaped, an outstanding ramp function appeared in the displacement seismogram obtained by simple integration. Since the ramp function appeared only in the horizontal components and continued for about 3 min, which is sufficiently longer than the natural period of the seismometer, we regarded the ramp function as an expression of the tilting motions of seismic stations that was quantitatively confirmed by the strong similarity between horizontal displacement seismograms and tilt data from co-located biaxial tiltmeter. Azimuthal distribution of three tilting vectors obtained from broadband seismograms was not consistent with a simple spherical source but rather strongly suggested a vertical dike under the crater. In this study, we confirmed that an almost vertical single dike effectively explains the observed tilting vectors. The estimated volume increase in the dike was 4-5 × 104 m3. The strike direction of the dike is highly consistent with the alignment of the hydrothermal area on and around the volcano. Our dike model also partially explains the changes in global navigation satellite system (GNSS) measurement and in groundwater levels reported in previous research. Since a similar deformation coincided with a volcanic tremor preceding the 2006

  13. Hydrothermal activity at Campi Flegrei caldera: rock mechanical properties and implications for outgassing and possible phreatic eruptions

    NASA Astrophysics Data System (ADS)

    Mayer, K.; Montanaro, C.; Scheu, B.; Isaia, R.; Mangiacapra, A.; Gresse, M.; Vandemeulebrouck, J.; Moretti, R.; Dingwell, D. B.

    2015-12-01

    The Solfatara and Pisciarelli fumaroles are the main surface manifestations of the vigorous hydrothermal activity within the Campi Flegrei caldera system. The existing fault system appears to have a major control on outgassing and leads to a strong alteration of the volcanic products in both areas. Consistent with the volcanic history of the area, Solfatara and Pisciarelli are posited as having the highest probability for the opening of new vents, and in particular for possible phreatic activity within the Campi Flegrei system. Hydrothermal alteration deeply affects all the rocks exposed within Solfatara sector, including lava domes, breccias, as well as pyroclastic fallout ash beds and pyroclastic density current deposits. This results in changes of the volcanic rock's original microstructure and of their physical and mechanical properties, which in turn control both the outgassing and their fragmentation behaviors. Here, samples from the wall rocks in the vicinity of the Solfatara and Pisciarelli fumaroles have been subjected to geochemical, physical and mechanical properties characterization. In addition, surficial Solfatara crater floor deposits were characterized and their properties, in particular permeability, were mapped. Results show that hydrothermal alteration increases porosity and permeability of the crater wall samples favoring outgassing, while decreasing the rock strength. At the crater floor the outgassing occurs mainly along the crack system, which has also generated crusted hummocks. Elsewhere the fluid circulation in the subsoil is favored by the presence of coarse and sulfur-hardened levels, whereas their surfacing is hindered by compacted fine-grained, low permeability layers. Decompression experiments were performed to simulate a phreatic eruption at shallow depth. We used crater-wall samples representing the rocks in the proximity of high degassing areas. Changes in the fragmentation behavior and ejection dynamics, depending on the

  14. The 1997 phreatic eruption of Akita-Yakeyama volcano, northeast Japan: Insight into the hydrothermal processes

    NASA Astrophysics Data System (ADS)

    Nogami, K.; Hirabayashi, J.; Ohba, T.; Yoshiike, Y.

    2000-04-01

    A small-scale steam explosion occurred on Karanuma crater on the summit of Akita-Yakeyama volcano on August 16, 1997 after a dormancy of 46 years. Chemical compositions of the fumarolic gases at the summit and hot spring waters around the volcano were monitored before the eruption.Obvious changes in the composition and outlet temperatures of the fumarolic gases were not detected, neither before nor after the 1997 eruption. Hydrogen and oxygen isotopic ratios of the gas condensates and hot-spring waters at the Yunuma crater indicated that a hydrothermal reservoir, where the fumarolic gases separated from the hot-spring waters at 150circC, existed in a shallow place beneath the crater.Smectite, kaolinite and pyrophyllite were identified in the clay fraction of the volcanic ejecta. Although pyrophyllite should have been formed at about 1~km beneath the summit, it was not directly derived from the deep zone during the 1997 eruption but had been ejected by previous eruptions. The Cl/S values of the water leachates of the ejecta were about 0.7, which indicated that the volcanic gas which caused the eruption was rich in HCl. However, the fumarolic gases and the water samples collected from the summit area contained little chloride. The source of the water-soluble chloride might be high-temperature magmatic gases that have been estimated as the source of Cl-SO4 type thermal water. Such magmatic gases might have caused the 1997 eruption.

  15. Hydrothermal alteration of surficial rocks at Solfatara (Campi Flegrei): Petrophysical properties and implications for phreatic eruption processes

    NASA Astrophysics Data System (ADS)

    Mayer, Klaus; Scheu, Bettina; Montanaro, Cristian; Yilmaz, Tim I.; Isaia, Roberto; Aßbichler, Donjá; Dingwell, Donald B.

    2016-06-01

    Solfatara crater is located within the Campi Flegrei caldera to the west of Naples (Italy). It is one of the largest fumarolic manifestations known, and the rocks hosting the hydrothermal system are affected by intense hydrothermal alteration. Alteration can result in changes of degassing behavior, and in the formation of a cap rock thereby increasing the probability of phreatic eruptions. Here, we investigate the effects of alunitic (solfataric) alteration on the mineralogy, the physical properties (porosity, density, permeability) and the mechanical properties (strength) of the rocks involved, as well as its influence on fragmentation and ejection behavior. Our results show that the pristine mineralogy of deposits from the vicinity of the Solfatara cryptodome and from Pisciarelli is almost completely replaced by amorphous silica and alunite. The differences in the degree of alteration among the samples series are reflected in the investigated properties and behavior as well as in the analysis of the experimentally generated particles. Alunitic alteration increases porosity and permeability, whereas it reduces density, elastic wave velocity and strength leading to higher fragmentation and ejection speeds for the sample series examined in this study. Our results also show that alteration results in the generation of a high fraction of fines (particle sizes < 10 μm) during fragmentation, mainly composed of alunite crystals. Due to their potential for inducing chronic disease, dispersion of such material should represent a serious health hazard on a local scale and the evaluation of precautions should be considered.

  16. Assessing the impact of dairy waste lagoons on groundwater quality using a spatial analysis of vadose zone and groundwater information in a coastal phreatic aquifer.

    PubMed

    Baram, S; Kurtzman, D; Ronen, Z; Peeters, A; Dahan, O

    2014-01-01

    Dairy waste lagoons are considered to be point sources of groundwater contamination by chloride (Cl(-)), different nitrogen-species and pathogens/microorganisms. The objective of this work is to introduce a methodology to assess the past and future impacts of such lagoons on regional groundwater quality. The method is based on a spatial statistical analysis of Cl(-) and total nitrogen (TN) concentration distributions in the saturated and the vadose (unsaturated) zones. The method provides quantitative data on the relation between the locations of dairy lagoons and the spatial variability in Cl(-) and TN concentrations in groundwater. The method was applied to the Beer-Tuvia region, Israel, where intensive dairy farming has been practiced for over 50 years above the local phreatic aquifer. Mass balance calculations accounted for the various groundwater recharge and abstraction sources and sinks in the entire region. The mass balances showed that despite the small surface area covered by the dairy lagoons in this region (0.8%), leachates from lagoons have contributed 6.0% and 12.6% of the total mass of Cl(-) and TN (mainly as NO3(-)-N) added to the aquifer. The chemical composition of the aquifer and vadose zone water suggested that irrigated agricultural activity in the region is the main contributor of Cl(-) and TN to the groundwater. A low spatial correlation between the Cl(-) and NO3(-)-N concentrations in the groundwater and the on-land location of the dairy farms strengthened this assumption, despite the dairy waste lagoon being a point source for groundwater contamination by Cl(-) and NO3(-)-N. Mass balance calculations, for the vadose zone of the entire region, indicated that drying of the lagoons would decrease the regional groundwater salinization process (11% of the total Cl(-) load is stored under lagoons). A more considerable reduction in the groundwater contamination by NO3(-)-N is expected (25% of the NO3(-)-N load is stored under lagoons). Results

  17. Recharging the phreatic aquifer in the upper Friuli plain, Italy, by a large infiltration basin

    NASA Astrophysics Data System (ADS)

    Nieto, Daniel; Affatato, Alessandro; Carvalho, Tiago; Ziska Gutz, Anna; Carvalho, Jose Martin; Mattassi, Giorgio; Brandolin, Davide; Canali, Massimo; Bongiovanni, Stefano; Castelletto, Nicola; Teatini, Pietro

    2013-04-01

    Even though the Friuli Region, northern Italy, is one of Italy's rainiest areas with an average yearly rainfall that ranges between 1300 mm along the cost up to 3000 mm at the Alps foothills, the groundwater level is continuously decreasing over the last years. To cope with this reduction of water availability and increase the subsurface storage of high-quality surficial waters that usually are lost during winter flowing into the northern Adriatic Sea, an artificial recharge project is ongoing within the WARBO LIFE+ Project funded by EU. WARBO is aimed at implementing large-scale use of artificial recharge in Italy where water directives still strongly limit its application. The project involves regional authorities and public and private stakeholders operating in the field of water management and treatment with the aim of guaranteeing the future application of the defined methods and the development of specific experimental protocols to overcome the boundaries posed by the current legislation. In this context, the Mereto recharge site selected in the upper Fruili plain is emblematic. Here a large infiltration basin, about 6 m deep and 45×7 m2 wide, was built in the early 2000s but the use was prohibited by law soon after the construction. Only recently, within the WARBO Project, the possibility of implementing the recharge has been allowed. The site is characterized by an elevation of 105 m above msl and the depth to the water table averages 50 m. Below a few meter-thick organic soil, the aquifer is composed by coarse deposits with an estimated thickness of 225 m and an average vertical hydraulic conductivity equal to 10-4 m/s. A 0.1 m3/s infiltration flow has been preliminary estimated (corresponding to an infiltration rate of 60 cm/h), with the water availability that is guaranteed during winter period by an irrigation channel connected to the Tagliamento and Ledra River. The contribution describes the geophysical investigations and in-situ tests carried out to

  18. Ecohydrological factors affecting nitrate concentrations in a phreatic desert aquifer in northwestern China

    USGS Publications Warehouse

    Gates, J.B.; Böhlke, J.K.; Edmunds, W.M.

    2008-01-01

    Aerobic conditions in desert aquifers commonly allow high nitrate (NO 3-) concentrations in recharge to persist for long periods of time, an important consideration for N-cycling and water quality. In this study, stable isotopes of NO3- (??15N NO3 and ??18ONO3) were used to trace NO3- cycling processes which affect concentrations in groundwater and unsaturated zone moisture in the arid Badain Jaran Oesert in northwestern China. Most groundwater NO3- appears to be depleted relative to Cl- in rainfall concentrated by evapotranspiration, indicating net N losses. Unsaturated zone NO 3- is generally higher than groundwater NO 3- in terms of both concentration (up to 15 476 ??M, corresponding to 3.6 mg NO3--N per kg sediment) and ratios with Cl-. Isotopic data indicate that the NO3- derives primarily from nitrification, with a minor direct contribution of atmospheric NO3- inferred for some samples, particularly in the unsaturated zone. Localized denitrification in the saturated zone is suggested by isotopic and geochemical indicators in some areas. Anthropogenic inputs appear to be minimal, and variability is attributed to environmental factors. In comparison to other arid regions, the sparseness of vegetation in the study area appears to play an important role in moderating unsaturated zone NO3- accumulation by allowing solute flushing and deterring extensive N2 fixation. ?? 2008 American Chemical Society.

  19. Monitoring system for phreatic eruptions and thermal behavior on Poás volcano hyperacidic lake, with permanent IR and HD cameras

    NASA Astrophysics Data System (ADS)

    Ramirez, C. J.; Mora-Amador, R. A., Sr.; Alpizar Segura, Y.; González, G.

    2015-12-01

    Monitoring volcanoes have been on the past decades an expanding matter, one of the rising techniques that involve new technology is the digital video surveillance, and the automated software that come within, now is possible if you have the budget and some facilities on site, to set up a real-time network of high definition video cameras, some of them even with special features like infrared, thermal, ultraviolet, etc. That can make easier or harder the analysis of volcanic phenomena like lava eruptions, phreatic eruption, plume speed, lava flows, close/open vents, just to mention some of the many application of these cameras. We present the methodology of the installation at Poás volcano of a real-time system for processing and storing HD and thermal images and video, also the process to install and acquired the HD and IR cameras, towers, solar panels and radios to transmit the data on a volcano located at the tropics, plus what volcanic areas are our goal and why. On the other hand we show the hardware and software we consider necessary to carry on our project. Finally we show some early data examples of upwelling areas on the Poás volcano hyperacidic lake and the relation with lake phreatic eruptions, also some data of increasing temperature on an old dome wall and the suddenly wall explosions, and the use of IR video for measuring plume speed and contour for use on combination with DOAS or FTIR measurements.

  20. Imaging the hydrothermal system beneath the Jigokudani valley, Tateyama volcano, Japan: implications for structures controlling repeated phreatic eruptions from an audio-frequency magnetotelluric survey

    NASA Astrophysics Data System (ADS)

    Seki, Kaori; Kanda, Wataru; Ogawa, Yasuo; Tanbo, Toshiya; Kobayashi, Tomokazu; Hino, Yuta; Hase, Hideaki

    2015-01-01

    This study focuses on the results of an audio-frequency magnetotelluric (AMT) survey across the Jigokudani valley, Tateyama volcano, Japan, to investigate the spatial relationship between the distribution of electrical resistivity and geothermal activity and to elucidate the geologic controls on both its phreatic eruption history and recent increase in phreatic activity. The AMT data were collected at eight locations across the Jigokudani valley in September 2013, with high quality data obtained from most sites, enabling the identification of an underground 2D resistivity structure from the transverse magnetic (TM) mode data. The data obtained during this study provided evidence of a large conductive region beneath the surface of the Jigokudani valley that is underlain by a resistive layer at depths below 500 m. The resistive layer is cut by a relatively conductive region that extends subvertically toward the shallow conductor. The shallow conductive region is divided into an uppermost slightly conductive section that is thought to be a lacustrine sediment layer of an extinct crater lake containing hydrothermal fluids and a lower section containing a mix of volcanic gases and hydrothermal fluids. The low permeability of the clay zone means that the uppermost clayey sediments allow the accumulation of gases in the lower section of the conductive region, suggesting the existence of a cap structure. The deep resistive layer likely consists of units similar to the granitic rocks that are widely exposed throughout the Jigokudani valley. We suggest that the relatively conductive zone that separates these granitic rocks represents a high-temperature volcanic gas conduit, given that the most active fumarole in the Jigokudani valley lies directly along the trajectory of this path.

  1. FIELD TEST OF CYCLODEXTRIN FOR ENHANCED IN-SITU FLUSHING OF MULTIPLE-COMPONENT IMMISCIBLE ORGANIC LIQUID CONTAMINATION: COMPARISON TO WATER FLUSHING

    EPA Science Inventory

    A pilot-scale field experiment was conducted to compare the remediation effectiveness of an enhanced-solubilization technique to that of water flushing for removal of multicomponent nonaqueous-phase organic liquid (NAPL) contaminants form a phreatic aquifer. This innovative remed...

  2. Water chemistry at Snowshoe Mountain, Colorado: mixed processes in a common bedrock

    USGS Publications Warehouse

    Hoch, A.R.; Reddy, M.M.

    2001-01-01

    At Snowshoe Mountain the primary bedrock is quite homogeneous, but weathering processes vary as waters moves through the soils, vadose zone and phreatic zone of the subsurface. In the thin soil, physical degradation of tuff facilitates preferential dissolution of potassium ion from glass within the rock matrix, while other silicate minerals remain unaltered. In the vadose zone, in the upper few meters of fractured bedrock, dilute water infiltrates during spring snowmelt and summer storms, leading to preferential dissolution of augite exposed on fracture surfaces. Deeper yet, in the phreatic zone of the fractured bedrock, Pleistocene calcite fracture fillings dissolve, and dioctahedral and trioctahedral clays form as penetrative weathering alters feldspar and pyroxene. Alkalinity is generated and silica concentrations are buffered by mineral alteration reactions.

  3. Floodplain ecohydrology: Climatic, anthropogenic, and local physical controls on partitioning of water sources to riparian trees

    PubMed Central

    Singer, Michael Bliss; Sargeant, Christopher I; Piégay, Hervé; Riquier, Jérémie; Wilson, Rob J S; Evans, Cristina M

    2014-01-01

    Seasonal and annual partitioning of water within river floodplains has important implications for ecohydrologic links between the water cycle and tree growth. Climatic and hydrologic shifts alter water distribution between floodplain storage reservoirs (e.g., vadose, phreatic), affecting water availability to tree roots. Water partitioning is also dependent on the physical conditions that control tree rooting depth (e.g., gravel layers that impede root growth), the sources of contributing water, the rate of water drainage, and water residence times within particular storage reservoirs. We employ instrumental climate records alongside oxygen isotopes within tree rings and regional source waters, as well as topographic data and soil depth measurements, to infer the water sources used over several decades by two co-occurring tree species within a riparian floodplain along the Rhône River in France. We find that water partitioning to riparian trees is influenced by annual (wet versus dry years) and seasonal (spring snowmelt versus spring rainfall) fluctuations in climate. This influence depends strongly on local (tree level) conditions including floodplain surface elevation and subsurface gravel layer elevation. The latter represents the upper limit of the phreatic zone and therefore controls access to shallow groundwater. The difference between them, the thickness of the vadose zone, controls total soil moisture retention capacity. These factors thus modulate the climatic influence on tree ring isotopes. Additionally, we identified growth signatures and tree ring isotope changes associated with recent restoration of minimum streamflows in the Rhône, which made new phreatic water sources available to some trees in otherwise dry years. Key Points Water shifts due to climatic fluctuations between floodplain storage reservoirs Anthropogenic changes to hydrology directly impact water available to trees Ecohydrologic approaches to integration of hydrology afford new

  4. Water

    MedlinePlus

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  5. Water

    MedlinePlus

    ... Shopping Tips Food Safety Common Questions Learn More Water Printer-friendly It’s important for your body to have plenty of fluids each day. Water helps you digest food, absorb nutrients from food, ...

  6. Water

    MedlinePlus

    ... water (like a lake) or to groundwater (the fresh water found under the Earth’s surface that supplies wells ... Too much harmful algae (say: AL-jay) in freshwater or seawater can make beaches unsafe for people. ...

  7. Chemistry of thermal waters and mineralogy of the new deposits at Mount St. Helens: a preliminary report

    SciTech Connect

    Dethier, D.P.; Frank, D.; Peavear, D.R.

    1980-12-01

    After May 18, 1980 eruption of Mount St. Helens, Washington, interactions between the hot deposits and shallow ground water produced ephemeral phreatic eruptions and thermal ponds and streams. In early June water and sediment samples were collected from about 20 sites in the devastated zone to study the initial alteration of the new deposits, and the effects of the eruption on water chemistry. The levels of certain trace elements in thermal waters, and whether these mineralized waters were reaching the North Fork Toutle River in appreciable quantities were studied. Collection and analysis procedures, the mineralogy of the new deposits, and the chemistry of the thermal waters are discussed. Finally, the chemistry of water from different deposits is compared, alteration reactions suggested by the water chemistry, and the mineralogy of the deposits is discussed.

  8. Study Relating to the Spatial Distribution of Ground Water Quality for Different Elements using Legacy Data of RWS&S, Andhra Pradesh, India

    NASA Astrophysics Data System (ADS)

    Prakash, P.; Das, A. Kumar; Sandilya, C. V. S.

    2014-11-01

    The state of Andhra Pradesh, India falls in water stress4 area. The primary objective of this study is to examine the spatial distribution of different chemical elements with respect to its contamination level. About 70 % of drinking water needs in rural areas and 40 % drinking water needs in urban areas are met from groundwater resources. In the last decades, rapid population growth coupled with agricultural expansion due to subsidized power to agriculture has significantly increased demand on groundwater resources. Combined to this, the effect of Global warming has put stress on ground water which is resulting in declines in water levels and deterioration of ground water quality. This may be evidenced by the fact that the phreatic aquifer which was in use two decades ago, is existing no more now in some of the parts of the study area and the water is being drawn from deeper aquifers beyond phreatic aquifers. The study has been carried out for which one or more elements are contaminated and to study its spatial distribution.

  9. Sub-annual variability in historical water source use by Mediterranean riparian trees.

    NASA Astrophysics Data System (ADS)

    Sargeant, Christopher; Singer, Michael

    2016-04-01

    The seasonal availability of water within a tree's rooting zone may be an important determinant for individual tree growth and overall forest health, particularly in riparian corridors of Mediterranean climate zones that are vulnerable to water stress. Here, we present a new method that combines dendro-isotopes and isotope-modelling for determining how water source use varies over 10 consecutive growing seasons (2000-2010) for co-occurring species P. nigra and F. excelsior, along the Rhône River, south-eastern France. We conducted highly resolved cellulose δ18O analysis of micro-slices within tree rings and back-calculated the δ18O signature of source water available at the time of growth using a biochemical fractionation model. We related these patterns to inferred seasonal hydrological partitioning through comparison with δ18O of waters from the vadose and phreatic zones, precipitation, and streamflow. The shallowly rooted Fraxinus displayed greater sub-annual source water variability, as well as greater isotopic enrichment, reflecting use of precipitation-derived vadose moisture. Its earlywood component was formed mainly from winter rainfall (depleted) whilst the latewood relied on growing season precipitation (enriched). In Populus, the sub-annual source water use was relatively depleted, suggesting use of hyporheic water and regional groundwater. From 2007, both species converged in their pattern of water source uptake which was attributed to a decline in phreatic water access for Populus. These results demonstrate that the seasonal variability in source water use can be identified retrospectively, a method which may prove important for anticipating the future consequences of climatic driven changes to the hydrological cycle.

  10. Water, vapour and heat transport in concrete cells for storing radioactive waste

    NASA Astrophysics Data System (ADS)

    Carme Chaparro, M.; Saaltink, Maarten W.

    2016-08-01

    Water is collected from a drain situated at the centre of a concrete cell that stores radioactive waste at 'El Cabril', which is the low and intermediate level radioactive waste disposal facility of Spain. This indicates flow of water within the cell. 2D numerical models have been made in order to reproduce and understand the processes that take place inside the cell. Temperature and relative humidity measured by sensors in the cells and thermo-hydraulic parameters from laboratory test have been used. Results show that this phenomenon is caused by capillary rise from the phreatic level, evaporation and condensation within the cell produced by temperature gradients caused by seasonal temperature fluctuations outside. At the centre of the cell, flow of gas and convection also play a role. Three remedial actions have been studied that may avoid the leakage of water from the drain.

  11. An examination of short-term variations in water quality at a karst spring in Kentucky

    SciTech Connect

    Ryan, M.; Meiman, J.

    1996-01-01

    Water quality at many karst springs undergoes very high amplitude but relatively brief degradation following influxes of runoff. Accurately recording transient variations requires more rigorous sampling strategies than traditional methods. A pilot study to determine the usefulness of high-frequency, flow-dependent sampling strategies, combined with coincidental quantitative dye tracer tests, was implemented in the Big Spring Ground-Water Basin in Mammoth Cave National Park, Kentucky. Data recorded following two separate runoff events showed that the concentrations of two nonpoint source pollutants, fecal coliform bacteria and suspended sediment, greatly exceeded prerunoff event values for very short periods of time. A phreatic conduit segment, calculated at 17 million liters in volume, instantaneously propagated head changes, caused by direct runoff entering the aquifer, from the ground-water inputs to Big Spring. A significant delay between the initial increases in discharge and the arrival of direct runoff, as indicated by a steady decrease in specific conductance, represented the time required to displace this volume of phreatic water. The delay showed that sampling a karst spring only during peak discharge would be an unreliable sampling method. Runoff from two different subcatchments was tagged with tracer dye and the timing of the passage of the resultant dye clouds through Big Spring were compared to water quality variations. Distinct lag times between the arrival of direct runoff at Big Spring and the bacteria and suspended sediment waveforms were shown through the concurrent quantitative tracer tests to be related to the areal distribution of land-cover type within the basin.

  12. Water subsidies from mountains to deserts: their role in sustaining groundwater-fed oases in a sandy landscape.

    PubMed

    Jobbágy, E G; Nosetto, M D; Villagra, P E; Jackson, R B

    2011-04-01

    In arid regions throughout the world, shallow phreatic aquifers feed natural oases of much higher productivity than would be expected solely from local rainfall. In South America, the presence of well-developed Prosopis flexuosa woodlands in the Monte Desert region east of the Andes has puzzled scientists for decades. Today these woodlands provide crucial subsistence to local populations, including descendants of the indigenous Huarpes. We explore the vulnerability and importance of phreatic groundwater for the productivity of the region, comparing the contributions of local rainfall to that of remote mountain recharge that is increasingly being diverted for irrigated agriculture before it reaches the desert. We combined deep soil coring, plant measurements, direct water-table observations, and stable-isotopic analyses (2H and 18O) of meteoric, surface, and ground waters at three study sites across the region, comparing woodland stands, bare dunes, and surrounding shrublands. The isotopic composition of phreatic groundwaters (delta2H: -137 per thousand +/- 5 per thousand) closely matched the signature of water brought to the region by the Mendoza River (-137 per thousand +/- 6 per thousand), suggestin that mountain-river infiltration rather than in situ rainfall deep drainage (-39 per thousand +/- 19 per thousand) was the dominant mechanism of recharge. Similarly, chloride mass balances determined from deep soil profiles (> 6 m) suggested very low recharge rates. Vegetation in woodland ecosystems, where significant groundwater discharge losses, likely >100 mm/yr occurred, relied on regionally derived groundwater located from 6.5 to 9.5 m underground. At these locations, daily water-table fluctuations of 10 mm, and stable-isotopic measurements of plant water, indicated groundwater uptake rates of 200-300 mm/yr. Regional scaling suggests that groundwater evapotranspiration reaches 18-42 mm/yr across the landscape, accounting for 7 17% of the Mendoza River flow

  13. Southern Dobrogea coastal potable water sources and Upper Quaternary Black Sea level changes

    NASA Astrophysics Data System (ADS)

    Caraivan, Glicherie; Stefanescu, Diana

    2013-04-01

    Southern Dobrogea is a typical geologic platform unit, placed in the south-eastern part of Romania, with a Pre-Cambrian crystalline basement and a Paleozoic - Quaternary sedimentary cover. It is bordered to the north by the Capidava - Ovidiu fault and by the Black Sea to the east. A regional WNW - ESE and NNE - SSW fault system divides the Southern Dobrogea structure in several tectonic blocks. Four drinking water sources have been identified: surface water, phreatic water, medium depth Sarmatian aquifer, and deep Upper Jurassic - Lower Cretaceous aquifer. Surface water sources are represented by several springs emerged from the base of the loess cliff, and a few small rivers, barred by coastal beaches. The phreatic aquifer develops at the base of the loess deposits, on the impervious red clay, overlapping the Sarmatian limestones. The medium depth aquifer is located in the altered and karstified Sarmatian limestones, and discharges into the Black Sea. The Sarmatian aquifer is unconfined where covered by silty loess deposits, and locally confined, where capped by clayey loess deposits. The aquifer is supplied from the Pre-Balkan Plateau. The Deep Upper Jurassic - Lower Cretaceous aquifer, located in the limestone and dolomite deposits, is generally confined and affected by the regional WNW - ESE and NNE - SSW fault system. In the south-eastern Dobrogea, the deep aquifer complex is separated from the Sarmatian aquifer by a Senonian aquitard (chalk and marls). The natural boundary of the Upper Jurassic - Lower Cretaceous aquifer is the Capidava - Ovidiu Fault. The piezometric heads show that the Upper Jurassic - Lower Cretaceous aquifer is supplied from the Bulgarian territory, where the Upper Jurassic deposits crop out. The aquifer discharges into the Black Sea to the east and into Lake Siutghiol to the northeast. The cyclic Upper Quaternary climate changes induced drastic remodeling of the Black Sea level and the corresponding shorelines. During the Last Glacial

  14. Origin of water salinity in a lake and coastal aquifer system

    NASA Astrophysics Data System (ADS)

    Djabri, L.; Rouabhia, A.; Hani, A.; Lamouroux, Ch.; Pulido-Bosch, A.

    2008-04-01

    The studied area is in the Algerian Northeast. A number of interacting factors at the site are able to modify salinity. The main influences are: (1) The lithology, (2) Fedzara Lake, (3) marine waters, and (4) a prolonged drought. (1) The lithology is very clearly delineated by the outcrop of metamorphic formations (gneiss, marbles, micaschists, and quartzites) and sedimentary formations (limestones, clay, sandstones, and sands). All these formations can influence the chemical composition of waters. (2) Fedzara Lake evacuates its salted waters via the Wadi Meboudja, which connects with the Wadi Seybouse and the phreatic surface. These lake waters might induce changes in salinity. (3) The marine waters represent the third source of salinity change. Over-pumping of water from wells and drillings can cause an imbalance to the fresh salted water interface. (4) The effects of a local prolonged drought of more than 10 years may increase water salinity. Over-pumping to augment water supply generates a fall in water levels and the drier atmosphere increases evapotranspiration. Both may contribute to increased salinity. Results of water analysis were used to observe the evolution of these various factors.

  15. Surface water and groundwater characteristics in the wetlands of the Ajó River (Argentina)

    NASA Astrophysics Data System (ADS)

    Carol, E. S.; Dragani, W. C.; Kruse, E. E.; Pousa, J. L.

    2012-10-01

    Intertidal wetlands are complex hydrological environments in which surface water and groundwater interact periodically with tidal flows. This work analyzes how the tidal flow determines the hydrodynamics and salinity of surface water and groundwater at different depths in the intertidal wetland located in the marsh of the Ajó River. Water level and salinity measurements were obtained from the Ajó River, the channels discharging into the river and the phreatic aquifer. The results in the natural marsh indicate the presence of saline stratification and that the surface water-groundwater relationship varies with the tide. At low tide, the water table discharges into the surface watercourses, and when the high tide rises above the regional groundwater discharge level, the tidal flow contributes to the water table, which causes an increase in salinity in surface water and groundwater. When the high tide does not rise above the discharge level, the tidal flow only enters the groundwater at the mouth section and the salinity of the surface water and groundwater decreases from low tide to high tide. In the marsh areas excluded from the tidal cycle due to the presence of floodgates, the water table always discharges into the canals, and in the surface water and groundwater there is no presence of saline stratification. The results obtained make it possible to generate a conceptual model of hydrological behaviour which shows the hydrodynamic and hydrochemical complexity of intertidal wetlands.

  16. Water table controlled syndepositional alteration textures and fabrics in salt pan halite: Modern analogues and ancient examples

    SciTech Connect

    Holt, R.M. ); Powers, D.W.

    1991-03-01

    At the Devil's Golf Course, Death Valley, CA, vadose zone and phreatic zone alteration of subaqueously accumulated halite produces characteristic textures and fabrics that are recognizable in ancient salt pan halite (Late Permian Salado Formation) exposed in a shaft at the Waste Isolation Pilot Plant. Water table depth and duration control fabric type. The crystal size of surficial halite is reduced by hygroscopic alteration. Efflorescent crusts extend the capillary fringe to the surface along vertical permeability pathways. When the water table is shallow, planar dissolution in the vadose zone removes all or most halite from successive thin depositional sequences and progressively disrupts strata consisting of clay or sulfate into irregular strata, stringers, isolated blebs, and, ultimately, 'blebby' laminae. With a deeper water table, point dissolution occurs along vertically oriented permeability pathways (e.g., polygonal margins) producing characteristic textures. Vertical pits, pipes, and macropores form first. Then the surface becomes slightly hummocky as point solution pathways to the water table widen and coalesce. A complex terrain of spires, hummocks, and columns develops and exhibits characteristic pods and lenses of fine halite surrounded by and containing solution lags of insoluble material. Relief is reduced by solution, and lenses and pods of fine halite become smaller and less common. Ultimately, halite is entirely removed leaving only insoluble material. Halite cements grow in the phreatic zone. Halite passively fills voids in more mechanically competent halite. Displacive halite cements dilate fabrics within less competent bedded halite. These textures can be integrated into an idealized lithologic sequence for ancient salt pan halite.

  17. Influence of water saturation on rock failure - Implications for volcanic environments

    NASA Astrophysics Data System (ADS)

    Scheu, B.; Feneis, C.; Lavallee, Y.; Heap, M. J.; Dingwell, D. B.

    2011-12-01

    Water plays several important roles in the grand scheme of volcanism. As magmatic water, it influences magma generation transport and emplacement/eruption via its influence on the physicochemical properties of melts (e.g. rheology, diffusion, surface tension). As external water, it's role is manifold: (1) it is the driving force for the phreatic explosions which often are precursory to volcanic eruptions, (2) it may mix with magma and fuel phreatomagmatic eruptions, and (3) it has the ability to weaken and destabilize volcanic structures. Previous studies have shown that even small amounts of water may substantially weaken the strength of rocks. However the study of volcanic rocks is, in this respect, sparse. For this study we chose both volcanic rocks and volcanic host rocks (ranging from volcaniclastic sandstone to dacite) and compare their behaviour to that of Bentheim sandstone, an iconic rock type in rock mechanics. Two different experimental approaches are combined in this study. Firstly, we investigated the failure of rock specimens by rapid decompression using a shock-tube apparatus. Therein a rock sample is slowly pressurized with argon gas up to a maximum pressure of 50 MPa and then rapidly decompressed to atmospheric conditions. The decompression rates in this facility reach the order of 10 GPa/s and higher, allowing us to interpret these experiments as dynamic direct tensile strength tests. The experiments were carried out with varying degrees of water saturation in a temperature range from 20 to 300 °C. The degree of water saturation influences the fragmentation threshold (the minimum applied pressure required to fully fragment a sample) as well as the speed of the fragmentation process. Secondly, uniaxial compressive strength (UCS) tests and Brazilian tests were carried out to investigate, respectively, the compressive and (indirect) tensile strengths of dry and water-saturated samples. UCS tests were performed on 80 x 40mm cylinders under a strain

  18. Petrogenesis of cenozoic temperate water carbonates, South Australia

    SciTech Connect

    Noel, J.P.; Bone, Y.

    1988-01-01

    The Gambier Limestone is one of several extensive, shallow water, shelf carbonates of Eocene to Miocene age exposed along the southern margin of Australia. It is muddy to grainy bryozoan calcarenite, with accessory benthonic foraminifers and echinoids. The sediments, originally composed almost entirely of calcite or Mg-calcite, have been in vadose and phreatic environments for over 10 m.y., yet are virtually unlithified. The only cements of any consequence are epitaxial on echinoids. Numerous karst features, dolines, caves, speleothems, and surface karren attest to prolonged residence in the meteoric zone. The Gambier is presently one of the best freshwater aquifiers in Australia, with most flow intergranular and through sediments with over 30% porosity. Cementation is by minor intergranular pressure solution, which has developed under overburden of less than 100 m. The overlying Naracoorte Limestone (Miocene), a calcarenite of warmer water aspect, contains numerous aragonite molds and is cemented marblehard. The authors propose that such temperate-water calcite limestones are a better model for the meteoric diagenesis of calcite sediments of all ages than aragonite-rich tropical sediments. It is probable that many similar early and middle Paleozoic calcite limestones may have been in the meteoric zone for prolonged periods, yet contain little or no petrographic or geochemical record of such exposure.

  19. A new analytical solution of water table response to tidal fluctuations and its application to estimate aquifer properties at the Niijima Island, Japan

    NASA Astrophysics Data System (ADS)

    Aichi, Masaatsu; Shiokari, Megumi; Tokunaga, Tomochika

    A perturbation solution of the Boussinesq equation under the boundary condition of multi-tide at the coast was derived for evaluating the hydraulic parameters of phreatic aquifer from tidally induced fluctuation of water table. Then, the solution was applied to estimate the hydraulic parameters of the Shiro-mama formation at the Niijima Island, Japan, by fitting the solution to the results of continuous measurements of water table fluctuations. The estimated hydraulic transmissivities from both the amplitude and the phase were comparable and consistent with the results of analyses based on Dupuit-Ghyben-Herzberg model, suggesting that the obtained values, i.e., 0.12-1.7 m2/s were reasonable.

  20. Inference of Stream Network Fragmentation Patterns from Ground Water - Surface Water Interactions on the High Plains Aquifer

    NASA Astrophysics Data System (ADS)

    Chandler, D. G.; Yang, X.; Steward, D. R.; Gido, K.

    2007-12-01

    Stream networks in the Great Plains integrate fluxes from precipitation as surface runoff in discrete events and groundwater as base flow. Changes in land cover and agronomic practices and development of ground water resources to support irrigated agriculture have resulted in profound changes in the occurrence and magnitude of stream flows, especially near the Ogallala aquifer, where precipitation is low. These changes have demonstrably altered the aquatic habitat of western Kansas, with documented changes in fish populations, riparian communities and groundwater quality due to stream transmission losses. Forecasting future changes in aquatic and riparian ecology and groundwater quality requires a large scale spatially explicit model of groundwater- surface water interaction. In this study, we combine historical data on land use, stream flow, production well development and groundwater level observations with groundwater elevation modeling to support a geospatial framework for assessing changes in refugia for aquatic species in four rivers in western Kansas between 1965 and 2005. Decreased frequency and duration of streamflow occurred in all rivers, but the extent of change depended on the geomorphology of the river basin and the extent of groundwater development. In the absence of streamflow, refugia for aquatic species were defined as the stream reaches below the phreatic surface of the regional aquifer. Changes in extent, location and degree of fragmentation of gaining reaches was found to be a strong predictor of surface water occurrence during drought and a robust hydrological template for the analysis of changes in recharge to alluvial and regional aquifers and riparian and aquatic habitat.

  1. Quality and management of hot water of intercalary continental, northern Sahara of Algeria

    NASA Astrophysics Data System (ADS)

    Tifrani, Ala Eddine; Nezli, Imed Eddine

    2016-07-01

    The Algerian Sahara is the biggest desert in the world, and it is known by that the main climatic characters which are the high temperature and the low precipitations. The northern Sahara is a part of this big area, located on the south-east of Algeria. Due to the rarely and insufficient precipitations (1 to 180 mm per year) the need for water is a rising problem, so the main source are the ground water. There are three ground water aquifers in the area, the phreatic table, the terminal complex and the intercalary continental, our study is focused on the intercalary continental which is the biggest non recharged aquifer in the world, many studies national and international estimated the reserve of the water around 6 million m3. Existing between 1000 and 2000 m depth, this depth gives the water a lot of characterization which need to be noted and updated for example the temperature (around 50°C), and the high mineralization, because of the vast area and the difference in depths between wells, which is a reason of variety, the main goal is the determination of chemical and physical setting of this water.

  2. Modeling sea-water intrusion with open boundary conditions

    SciTech Connect

    Padilla, F.; Cruz-Sanjulian, J.

    1997-07-01

    The present study concerns the application of a new numerical approach to describe the fresh-water/sea-water relationships in coastal aquifers. Essentially, a solution to the partial differential equation governing the regional motion of a phreatic surface and the resulting interface between fresh water and salt water is analyzed by a Galerkin finite-element formulation. A single-phase steady numerical model was applied to approximate, with simple triangular elements, the regional behavior of a coastal aquifer under appropriate sinks, sources, Neumann, outflow face, and open boundary conditions. On the one hand, outflow open boundaries at the coastline were not treated with other classical boundary conditions, but instead with a formal numerical approach for open boundaries inspired in this particular case by the Dupuit approximation of horizontal outflow at the boundary. The solution to this numerical model, together with the Ghyben-Herzberg principle, allows the correct simulation of fresh-water heads and the position of the salt-water interface for a steeply sloping coast. Although the solutions were precise and do not present classical numerical oscillations, this approach requires a previous solution with Dirichlet boundary conditions at the coastline in order to find a good convergence of the solution algorithm. On the other hand, the same precise results were obtained with a more restrictive open boundary condition, similar in a way to the outflow face approach, which required less computer time, did not need a prior numerical solution and could be extended to different coastline conditions. The steady-state problem was solved for different hypothetical coastal aquifers and fresh-water usage through three types of numerical tests.

  3. Sub-annual Fluctuations in Water Sources Utilised by Mediterranean RiparianTrees Determined Through Highly Resolved Oxygen Isotope Analysis of Tree-ring Cellulose

    NASA Astrophysics Data System (ADS)

    Sargeant, C. I.; Singer, M. B.

    2014-12-01

    The sensitivity of trees to water availability within their rooting zones is a major determinant of tree and forest health. Yet, we have a poor understanding of subterranean water availability and its fluctuations due to climate. Such shortcomings limit our ability to predict how climatic variability will impact water availability to trees, and corresponding forest health. Understanding of water partitioning within the 'critical zone' of riparian areas are particularly lacking, especially in the vulnerable Mediterranean climate regimes. A substantial body of research uses isotope dendrochronology to assess riparian forest-water relations at annual (tree-ring) timescales, which integrate variability in seasonal hydrology. However, the sub-annual variations in water availability have been largely overlooked, which may have important ramifications for riparian ecohydrology. We present a new method for determining the sub-annual hydrologic variability within a floodplain forest using two co-occurring Mediterranean tree species along the Rhône River, southern France. We conducted oxygen isotope (δ18O) analysis of cellulose for 11 microslices within each tree ring to detect sub-annual patterns in δ18O that reflect the variability in hydrological partitioning. We back-calculated the seasonal time series of source waters used by the trees via a mechanistic model. Differences in rooting between the species allow us to constrain fluctuations in water availability and use between the vadose and phreatic zones. The two different species of streamside trees use distinct water sources and their seasonal patterns of water use are also fundamentally different. We develop strong links between these sub-annual patterns of δ18O signatures and the climatic characteristics of the hydrological year. We also present isotopic analyses of source waters from the vadose and phreatic zones, precipitation, and the Rhône to bolster our interpretations of water partitioning. This research

  4. A comparative molecular analysis of water-filled limestone sinkholes in north-eastern Mexico.

    PubMed

    Sahl, Jason W; Gary, Marcus O; Harris, J Kirk; Spear, John R

    2011-01-01

    Sistema Zacatón in north-eastern Mexico is host to several deep, water-filled, anoxic, karstic sinkholes (cenotes). These cenotes were explored, mapped, and geochemically and microbiologically sampled by the autonomous underwater vehicle deep phreatic thermal explorer (DEPTHX). The community structure of the filterable fraction of the water column and extensive microbial mats that coat the cenote walls was investigated by comparative analysis of small-subunit (SSU) 16S rRNA gene sequences. Full-length Sanger gene sequence analysis revealed novel microbial diversity that included three putative bacterial candidate phyla and three additional groups that showed high intra-clade distance with poorly characterized bacterial candidate phyla. Limited functional gene sequence analysis in these anoxic environments identified genes associated with methanogenesis, sulfate reduction and anaerobic ammonium oxidation. A directed, barcoded amplicon, multiplex pyrosequencing approach was employed to compare ∼100,000 bacterial SSU gene sequences from water column and wall microbial mat samples from five cenotes in Sistema Zacatón. A new, high-resolution sequence distribution profile (SDP) method identified changes in specific phylogenetic types (phylotypes) in microbial mats at varied depths; Mantel tests showed a correlation of the genetic distances between mat communities in two cenotes and the geographic location of each cenote. Community structure profiles from the water column of three neighbouring cenotes showed distinct variation; statistically significant differences in the concentration of geochemical constituents suggest that the variation observed in microbial communities between neighbouring cenotes are due to geochemical variation. PMID:20738374

  5. The hydrogeological role of an aquitard in preventing drinkable water well contamination: a case study.

    PubMed

    Ponzini, G; Crosta, G; Giudici, M

    1989-11-01

    Groundwater pollution has become a worrisome phenomenon, mainly for aquifers underlying industrialized areas. In order to evaluate the risk of pollution, a model of the aquifer is needed. Herewith, we describe a quasi-tridimensional model, which we applied to a multilayered aquifer where a phreatic aquifer was coupled to a confined one by means of an aquitard. This hydrogeological scheme is often met in practice and, therefore, models a number of situations. Moreover, aquitards play and important role in the management of natural resources of this kind. The model we adopted contains some approximations: the flow within the aquifers is assumed to be horizontal, whereas leakage is assumed vertical. The effect of some wells drilled in these aquifers is also taken into account. In order to evaluate the leakage fluxes that correspond to different exploitation conditions, we numerically solve a system of quasilinear and time-dependent partial differential equations. This model has been calibrated by the hydrogeological data from a water supply station of the Milan Water Works, where water is polluted by some halocarbons. Our simulations account for several experimental facts, both from the hydrogeological and hydrogeochemical viewpoints. Maxima of computed downward leakage rates are found to correspond with measured pollutant concentration maxima. Other results show how the aquitard can help in minimizing the contamination of drinkable water. PMID:2620670

  6. Petrogenesis of Cenozoic temperate water carbonates, south Australia: model for shallow-burial or meteoric diagenesis of Phanerozoic shallow water calcite sediments

    SciTech Connect

    James, N.P.; Bone, Y.

    1988-02-01

    The Gambier Limestone is one of several extensive, shallow water, shelf carbonates of Eocene to Miocene age exposed along the southern margin of Australia. It is a muddy to grainy bryozoan calcarenite, with accessory benthonic foraminifers and echinoids. The sediments, originally composed almost entirely of calcite or Mg-calcite, have been in vadose and phreatic environments for over 10 m.y., yet are virtually unlithified. The only cements of any consequence are epitaxial on echinoids. Numerous karst features, dolines, caves, speleothems, and surface karren attest to prolonged residence in the meteoric zone. The Gambier is presently one of the best freshwater aquifers in Australia, with most flow intergranular and through sediments with over 30% porosity. Cementation is by minor intergranular pressure solution, which has developed under overburden of less than 100 m. The overlying Naracoorte Limestone (Miocene), a calcarenite of warmer water aspect, contains numerous aragonite molds and is cemented marble-hard. The authors propose that such temperate-water calcite limestones are a better model for the meteoric diagenesis of calcite sediments of all ages than aragonite-rich tropical sediments. It is probable that many similar early and middle Paleozoic calcite limestones may have been in the meteoric zone for prolonged periods, yet contain little or no petrographic or geochemical record of such exposure.

  7. Water, Water Everywhere

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2009-01-01

    Everybody knows that children love water and how great water play is for children. The author discusses ways to add water to one's playscape that fully comply with health and safety regulations and are still fun for children. He stresses the importance of creating water play that provides children with the opportunity to interact with water.

  8. Impact of switching crop type on water and solute fluxes in deep vadose zone

    NASA Astrophysics Data System (ADS)

    Turkeltaub, T.; Kurtzman, D.; Russak, E. E.; Dahan, O.

    2015-12-01

    Switching crop type and consequently changing irrigation and fertilization regimes lead to alterations in deep percolation and solute concentrations of pore water. Herein, observations from the deep vadose zone and model simulations demonstrate the changes in water, chloride, and nitrate fluxes under a commercial greenhouse following the change from tomato to lettuce cropping. The site, located above a phreatic aquifer, was monitored for 5 years. A vadose-zone monitoring system was implemented under the greenhouse and provided continuous data on both temporal variations in water content and chemical composition of the pore water at multiple depths in the deep vadose zone (up to 20 m). Following crop switching, a significant reduction in chloride concentration and dramatic increase in nitrate were observed across the unsaturated zone. The changes in chemical composition of the vadose-zone pore water appeared as sequential breakthroughs across the unsaturated zone, initiating at land surface and propagating down toward the water table. Today, 3 years after switching the crops, penetration of the impact exceeds 10 m depth. Variations in the isotopic composition of nitrate (18O and 15N) in water samples obtained from the entire vadose zone clearly support a fast leaching process and mobilization of solutes across the unsaturated zone following the change in crop type. Water flow and chloride transport models were calibrated to observations acquired during an enhanced infiltration experiment. Forward simulation runs were performed with the calibrated models, constrained to tomato and lettuce cultivation regimes as surface boundary conditions. Predicted chloride and nitrate concentrations were in agreement with the observed concentrations. The simulated water drainage and nitrogen leaching implied that the observed changes are an outcome of recommended agricultural management practices.

  9. Large-scale regionalization of water table depth in peatlands optimized for greenhouse gas emission upscaling

    NASA Astrophysics Data System (ADS)

    Bechtold, M.; Tiemeyer, B.; Laggner, A.; Leppelt, T.; Frahm, E.; Belting, S.

    2014-04-01

    Fluxes of the three main greenhouse gases (GHG) CO2, CH4 and N2O from peat and other organic soils are strongly controlled by water table depth. Information about the spatial distribution of water level is thus a crucial input parameter when upscaling GHG emissions to large scales. Here, we investigate the potential of statistical modeling for the regionalization of water levels in organic soils when data covers only a small fraction of the peatlands of the final map. Our study area is Germany. Phreatic water level data from 53 peatlands in Germany were compiled in a new dataset comprising 1094 dip wells and 7155 years of data. For each dip well, numerous possible predictor variables were determined using nationally available data sources, which included information about land cover, ditch network, protected areas, topography, peatland characteristics and climatic boundary conditions. We applied boosted regression trees to identify dependencies between predictor variables and dip well specific long-term annual mean water level (WL) as well as a transformed form of it (WLt). The latter was obtained by assuming a hypothetical GHG transfer function and is linearly related to GHG emissions. Our results demonstrate that model calibration on WLt is superior. It increases the explained variance of the water level in the sensitive range for GHG emissions and avoids model bias in subsequent GHG upscaling. The final model explained 45% of WLt variance and was built on nine predictor variables that are based on information about land cover, peatland characteristics, drainage network, topography and climatic boundary conditions. Their individual effects on WLt and the observed parameter interactions provide insights into natural and anthropogenic boundary conditions that control water levels in organic soils. Our study also demonstrates that a large fraction of the observed WLt variance cannot be explained by nationally available predictor variables and that predictors with

  10. Hydrologic connections and dynamics of water movement in the classical Karst (Kras) Aquifer: evidence from frequent chemical and stable isotope sampling

    USGS Publications Warehouse

    Doctor, Daniel H.

    2008-01-01

    A review of past research on the hydrogeology of the Classical Karst (Kras) region and new information obtained from a two- year study using environmental tracers are presented in this paper. The main problems addressed are 1) the sources of water to the Kras aquifer resurgence zone-including the famous Timavo springs-under changing flow regimes; 2) a quantification of the storage volumes of the karst massif corresponding to flow regimes defined by hydrograph recessions of the Timavo springs; and 3) changing dynamics between deep phreatic conduit flow and shallow phreatic and epiphreatic storage within the aquifer resurgence zone as determined through changes in chemical and isotopic composition at springs and wells. Particular focus was placed on addressing the long-standing question of the influence of the Soca River on the ground waters of the aquifer resurgence zone. The results indicate that the alluvial aquifer supplied by the sinking of the Soca River on the northwestern edge of the massif contributes approximately 75% of the mean annual outflow to the smaller springs of the aquifer resurgence zone, and as much as 53% to the mean annual outflow of the Timavo springs. As a whole, the Soca River is estimated to contribute 56% of the average outflow of the Kras aquifer resurgence. The proportions of Soca River water increase under drier conditions, and decrease under wetter conditions. Time series analysis of oxygen stable isotope records indicate that the transit time of Soca River water to the Timavo springs, Sardos spring, and well B-4 is on the order of 1-2 months, depending on hydrological conditions. The total baseflow storage of the Timavo springs is estimated to be 518 million m3, and represents 88.5% of the storage capacity estimated for all flow regimes of the springs. The ratio of baseflow storage volume to the average annual volume discharged at the Timavo springs is 0.54. The Reka River sinking in Slovenia supplies substantial allogenic recharge to

  11. Response of a sloping aquifer to constant replenishment and to stream varying water level

    NASA Astrophysics Data System (ADS)

    Zissis, T. S.; Teloglou, I. S.; Terzidis, G. A.

    2001-03-01

    The problem of seepage from a stream into an adjacent unconfined aquifer of semi-infinite extent, underlain by an impermeable sloping bed was considered in this study as a problem of one-dimensional unsteady-state groundwater flow. It was assumed that the water level in the stream gradually rises to a certain height, according to a known exponential function of time, while the aquifer was assumed to be replenished at a constant rate from ground surface. Applying the Laplace transformation method derived an analytical solution to an extended and linearized form of the nonhomogeneous Boussinesq equation used to describe the phreatic surface in sloping aquifers. The comparison of the analytical solution with a numerical solution obtained by applying the finite difference Mac Cormack explicit computational scheme to the nonlinear Boussinesq equation illustrates the validity of the new analytical solution and the effectiveness of the linearization. Some nondimensional diagrams are also presented to show the variation of the water table height and the seepage rate as well as their sensitivity to various sets of parameter values.

  12. Hydrogeological and isotopic study of surface water and groundwater in the Eastern Haouz Plain. Western Morocco

    NASA Astrophysics Data System (ADS)

    El Mandour, Abdennabi; Rochdane, Samia; Reddy, Venkat; Himi, Mahjoub; Casas, Albert

    2014-05-01

    The Eastern Haouz area, characterized by a semi-arid climate, is part of the Haouz plain. The basin is built over a broad synclinal between the High Atlas and the Jebilets mountains. The compilation of geological, geophysical and hydrogeological data shows that this area is straddling two major basins of western Morocco. Map of the river system and the piezometric map show the same division line of surface water and groundwater. This division line oriented NNW-SSE is evidenced by the rise of the basement constituted by Paleozoic schists that outcrop near Tamelalt. Thus we can distinguish two main directions of groundwater flow feeding two watersheds (Tensift and Oum Rabiaa rivers) and two large reservoirs in the region of Marrakech. As a contribution to solve the water supply problem in the area, a hydrochemical study has been conducted, involving 40 groundwater samples for major ions and 20 stable isotope analyses. Hydrochemical results show the geological control on water quality. Samples from Paleozoic schists and Triassic sediments are relatively highly mineralisation and unsuitable for drinking as well as for irrigation. Conversely, groundwater from the alluvial plains is relatively less mineralised than other older geological formations; however, many of the samples are also non-potable. Apart of salinity problem, about 25% of the samples have higher nitrate content than the drinking water permissible limit. Stable isotope analysis show that groundwater recharge to the phreatic aquifer is controlled by local conditions. The small difference in the isotopic content of river water and a group of groundwater samples is interpreted as the evaporation effect during the recharge. On the other hand, the group of samples with relatively depleted stable isotopic content shows faster recharge conditions and less water-rock interaction. Finally, another group of samples is relatively enriched in stable isotope content and confirm an increase during the recharge

  13. Groundwater Dynamics under Water Saving Irrigation and Implications for Sustainable Water Management in an Oasis: Tarim River Basin of Western China

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Hu, H.; Tian, F.; Yao, X.; Sivapalan, M.

    2014-02-01

    Water is essential for life. Specifically in the oases of inland arid basins, water is a critically limited resource, essential for the development of socio-economy and sustainability of eco-environmental systems. Due to the unique hydrological regime present in arid oases, a moderate groundwater table is the goal of sustainable water management. A shallow water table induces serious secondary salinization and collapse of agriculture, while a deep water table causes deterioration of natural vegetation. From the hydrological perspective, the exchange flux between unsaturated vadose zone and groundwater reservoir is a critical link to understand regional water table dynamics. This flux is substantially influenced by anthropogenic activities. In Tarim River Basin of western China, where agriculture consumes over 90% of available water resources, the exchange flux is influenced strongly by irrigation. Recently, mulched drip irrigation, a very advanced water-saving irrigation method, has been widely applied in the Tarim River Basin, which greatly impacted the exchange flux and thus the regional groundwater dynamics. Capitalizing on recent progress in evaporation measurement techniques, we can now close the water balance and directly quantify the exchange flux at the field scale, thus gain a better understanding of regional groundwater dynamics. In this study, comprehensive observations of water balance components in an irrigated cropland were implemented in 2011 and 2012 in a typical oasis within Tarim River Basin. The water balance analysis showed that the exchange flux and groundwater dynamics were significantly altered by the application of water-saving irrigation. The exchange flux is mostly downward (310.5 mm yr-1), especially during drip irrigation period and spring flush period, while the upward flux is trivial (-16.1 mm yr-1) due to the moderate groundwater table depth (annual average depth 2.9 m). Traditional secondary salinization caused by intense phreatic

  14. Groundwater dynamics under water-saving irrigation and implications for sustainable water management in an oasis: Tarim River basin of western China

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Hu, H.; Tian, F.; Yao, X.; Sivapalan, M.

    2014-10-01

    groundwater table depth (annual average depth 2.9 m). Traditional secondary salinization caused by intense phreatic evaporation (fed by upward exchange flux) is alleviated. However, a new form of secondary salinization may be introduced unwittingly if there is lack of water for periodic flushing, especially when brackish water is used in the irrigation. Furthermore, the water saved via drip irrigation has been used in further growth of irrigated lands instead of supporting the ecological system. This could lead to an increased risk of eco-environmental degradation and calls for improved governance schemes. The insights gained from this study can be potentially applied to other arid inland areas (e.g., central Asia) which face similar water shortages and human development problems.

  15. Volumetric estimates of ancient water on Mount Sharp based on boxwork deposits, Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Siebach, Kirsten L.; Grotzinger, John P.

    2014-01-01

    While the presence of water on the surface of early Mars is now well known, the volume, distribution, duration, and timing of the liquid water have proven difficult to determine. This study makes use of a distinctive boxwork-rich sedimentary layer on Mount Sharp to map fluid-based cementation from orbital imagery and estimate the minimum volume of water present when this sedimentary interval was formed. The boxwork structures on Mount Sharp are decameter-scale light-toned polygonal ridges that are unique compared to previous observations of Martian fractured terrain because they are parallel-sided ridges with dark central linear depressions. This texture and the sedimentary setting strongly imply that the ridges are early diagenetic features formed in the subsurface phreatic groundwater zone. High-resolution orbital imagery was used to map the volume of light-toned cemented ridges. Based on the cemented volume, a minimum of 5.25 × 105 m3 of cement was deposited within the fractures. Using a brine composition based on observations of other Martian cements and modeling the degree of evaporation, each volume of cement requires 800-6700 pore volumes of water, so the mapped boxwork ridge cements require a minimum of 0.43 km3 of water. This is a significant amount of groundwater that must have been present at the -3620 m level, 1050 m above the current floor of Gale Crater, providing both a new constraint on the possible origins of Mount Sharp and a possible future science target for the Curiosity rover where large volumes of water were present, and early mineralization could have preserved a once-habitable environment.

  16. Quantifying water sources to a semiarid riparian ecosystem, San Pedro River, Arizona

    NASA Astrophysics Data System (ADS)

    Baillie, Matthew N.; Hogan, James F.; Ekwurzel, Brenda; Wahi, Arun K.; Eastoe, Christopher J.

    2007-09-01

    The Upper San Pedro River Basin (Southeastern Arizona, United States) contains one of the few desert riparian areas in the Southwest, a system that is dependent on both shallow groundwater to support phreatic vegetation and baseflow for aquatic plants and animals. Proper management decisions for sustaining this biodiversity hotspot require understanding the hydrology of the riparian system and its interaction with the basin aquifer. To meet this need and to assess whether the techniques used would be efficient for evaluating other semiarid riparian ecosystems, we addressed the following questions. What are the contributions of different water sources (e.g., local recharge during monsoon flood events versus inflow of basin groundwater) to riparian groundwater and river baseflow? How does the spatial variability in water sources relate to gaining and losing reaches along of the river? We first characterize the possible water sources to the riparian system using a suite of geochemical tracers. Results indicate that, of the possible sources, basin groundwater recharged along the Huachuca Mountains to the west and local recharge of monsoon floodwaters are the dominant riparian water sources. Then, using their geochemical composition, we quantify these sources using a two end-member mixing model. We find that riparian groundwater composition varies between gaining and losing reaches. Locally recharged monsoon floodwater comprises 60 to 85% of riparian groundwater in losing reaches whereas that of gaining reaches contains only 10% to 40%. Baseflow, sampled year round, also contains a significant component of monsoon floodwater ranging from 80% on the upstream end and decreasing to 55% after passing though several gaining reaches. These results highlight the significance of local recharge during monsoon flood events as a water source for desert riparian systems, a fact that should be addressed when constructing and calibrating hydrologic models used to evaluate these

  17. Water-rock interaction induced by contaminated groundwater in a karst aquifer, Greece

    NASA Astrophysics Data System (ADS)

    Panagopoulos, G.; Lambrakis, N.; Katagas, C.; Papoulis, D.; Tsolis-Katagas, P.

    2005-12-01

    The karst system of SW Trifilia is composed of a thick sequence of carbonate sediments, which have experienced two types of dolomitization and dedolomitization processes and comprise an extended aquifer. The application of fertilizers in the region have not only caused the degradation of the groundwater quality but also induced hydrochemical changes exerting major control on dolomitization processes. Factor analysis indicates high correlation coefficient between NH{4/+}, NO{3/-}, Ca2+ and Mg2+, which can be attributed to cation-exchange processes involving clay minerals. The application of a conservative mixing model showed that the calculated groundwater types indicate a cation-exchange process between NH{4/+}, derived from fertilizers, and between Ca2+ and Mg2+. Mg2+ released from smectite interlayers, exchanged for NH{4/+} in the groundwater and favor a dolomitization process through the partial replacement of Ca2+ in the lattice of calcite (dedolomite) contained in precursor dolomites. This recent stage dolomitization occurred near the water level and within the phreatic zone only and had not influenced the whole karst massif; it also resulted in low Mg/Ca values found in the zone characterized by intensive application of nitrogen-based fertilizers and the absence of overlying impermeable strata.

  18. Water, Water, Everywhere.

    ERIC Educational Resources Information Center

    Fahey, John A.

    2000-01-01

    The brain needs energy, oxygen, and water to operate. Access to the bathroom pass can become a major conflict between teachers and students and has great potential for disrupting classes. The classroom can be humanized by granting more bathroom passes and allowing water bottles. (MLH)

  19. Water, Water, Everywhere.

    ERIC Educational Resources Information Center

    Selinger, Ben

    1979-01-01

    Water is a major component in many consumer products. Azeotropic distillation of products such as detergents and foodstuffs to form a two-phase distillate is a simple experimental method to determine the percentage of water in the product. (Author/GA)

  20. Water, water everywhere

    SciTech Connect

    Pennisi, E.

    1993-02-20

    The first part of this article describes the current understanding of the dynamic interaction between protein folding and function and water, dependent on the polarity of water. The second part examines the role of water in converting organic matter into oil and coal by summarizing the history and result of experiments done over the last 13 years by Exxon researchers. Water under pressure and at high temperatures (300 C) can act as a solvent, a catalyst, and a reagent. Organic molecules can be fragmented by high temperature, but water and brine can also fragment them, sometimes more effectively. The actual mechanism by which water works is still a matter of active investigation, but the fact that it can be involved in oil formation could weak havoc on established ideas. Among the possibilities in the immediate future using hot water include the following: introducing hydrogen to coal for easier liquefaction and cost reduction; add hydrogen to low quality oil deposits for better quality and easier extraction; increasing the efficiency of isopropyl alcohol production; breaking down petroleum based wastes to reduce environmental contamination.

  1. Healthy Water

    MedlinePlus

    ... Water Systems, Water Fluoridation, Camping, Hiking, Travel… Global Water, Sanitation, & Hygiene (WASH) Community Systems, Household Treatment & Storage, Sanitation and Hygiene, Travelers’ Health… WASH-related ...

  2. Estimation of baseflow and water transfer in karst catchments in Mediterranean Turkey by nonlinear recession analysis

    NASA Astrophysics Data System (ADS)

    Eris, Ebru; Wittenberg, Hartmut

    2015-11-01

    Because of water transfers through fissures, cavities, caves and phreatic channels of various sizes and unknown directions, the topographic watersheds of karst catchments have little significance for their aquifers. Most of the flow in the Manavgat River in South Anatolia has its origin outside of the surface watershed and is transferred through karst pathways. Previous investigations found evidence for this by groundwater tracing techniques. In this study, flow recession analysis and baseflow separation are applied to the time series of daily flows 1992-2008 from three gauging stations. Flow recessions were found corresponding to the nonlinear storage-baseflow relationship S = a·Qb, with b values around 0.5 as typical for unconfined groundwater, while the coefficient a showed marked seasonal variations with higher values in the rainy winter time and decreasing values towards the dry summer. For catchments which receive water transfers from other areas, the decrease of a is retarded. Flow recession is slower since more water is available. Baseflow separation by using the same nonlinear model revealed that direct flow, which is mainly surface flow, corresponds roughly to the surface catchments while baseflow, which accounts for most of the total flow, is highly influenced by transfers from karst sink areas outside the surface watersheds. The subsurface transfer was simulated by a nonlinear reservoir routing algorithm. Time series of monthly baseflow from catchments which receive transfer water were compared with those of sinkhole (loss) areas. The procedure allows inferring the origin area of the inflows and estimating the retention or lag time of the transfer.

  3. Water, Water Everywhere!

    ERIC Educational Resources Information Center

    Sible, Kathleen P.

    2000-01-01

    Describes how problems with water drainage on the playground, and the resulting puddles, provided a wealth of learning opportunities, children's fun, family-school communication, and challenges for one early childhood program. (KB)

  4. Drinking Water

    MedlinePlus

    We all need to drink water. How much you need depends on your size, activity level, and the weather where you live. The water you drink is a combination of surface water and groundwater. Surface water ...

  5. Water Works.

    ERIC Educational Resources Information Center

    Van De Walle, Carol

    1988-01-01

    Describes a two-day field trip, along with follow-up classroom activities and experiments which relate to water resources and water quality. Discusses how trips to a lake and water treatment facilities can enhance appreciation of water. (TW)

  6. Reconstructing water level in Hoyo Negro, Quintana Roo, Mexico, implications for early Paleoamerican and faunal access

    NASA Astrophysics Data System (ADS)

    Collins, S. V.; Reinhardt, E. G.; Rissolo, D.; Chatters, J. C.; Nava Blank, A.; Luna Erreguerena, P.

    2015-09-01

    The skeletal remains of a Paleoamerican (Naia; HN5/48) and extinct megafauna were found at -40 to -43 mbsl in a submerged dissolution chamber named Hoyo Negro (HN) in the Sac Actun Cave System, Yucatan Peninsula, Mexico. The human remains were dated to between 12 and 13 Ka, making these remains the oldest securely dated in the Yucatan. Twelve sediment cores were used to reconstruct the Holocene flooding history of the now phreatic cave passages and cenotes (Ich Balam, Oasis) that connect to HN. Four facies were found: 1. bat guano and Seed (SF), 2. lime Mud (MF), 3. Calcite Rafts (CRF) and 4. Organic Matter/Calcite Rafts (OM/CRF) which were defined by their lithologic characteristics and ostracod, foraminifera and testate amoebae content. Basal radiocarbon ages (AMS) of aquatic sediments (SF) combined with cave bottom and ceiling height profiles determined the history of flooding in HN and when access was restricted for human and animal entry. Our results show that the bottom of HN was flooded at least by 9850 cal yr BP but likely earlier. We also found, that the pit became inaccessible for human and animal entry at ≈8100 cal yr BP, when water reaching the cave ceiling effectively prevented entry. Water level continued to rise between ≈6000 and 8100 cal yr BP, filling the cave passages and entry points to HN (Cenotes Ich Balam and Oasis). Analysis of cave facies revealed that both Holocene sea-level rise and cave ceiling height determined the configuration of airways and the deposition of floating and bat derived OM (guano and seeds). Calcite rafts, which form on the water surface, are also dependent on the presence of airways but can also form in isolated air domes in the cave ceiling that affect their loci of deposition on the cave bottom. These results indicated that aquatic cave sedimentation is transient in time and space, necessitating extraction of multiple cores to determine a limit after which flooding occurred.

  7. Water, Water Everywhere, But...

    ERIC Educational Resources Information Center

    Jacobson, Cliff

    Materials for teaching a unit on water pollution are provided in this teaching package. These materials include: (1) a student reading booklet; (2) a reference booklet listing a variety of popular chemical, biological, and physical tests which can be performed on a local waterway and providing information about the environmental effects and toxic…

  8. Water Conditioner

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A home use water treatment incorporates technology developed to purify water aboard Space Shuttle Orbiters. The General Ionics Model IQ Bacteriostatic Water Softener softens water and inhibits bacteria growth in the filtering unit. Ionics used NASA silver ion technology as a basis for development of a silver carbon dense enough to remain on top of the water softening resin bed.

  9. Spongy-like porosity in peritidal carbonates: An interaction of cyclic sea-level oscillations, fresh water supply and sediment texture

    NASA Astrophysics Data System (ADS)

    Todaro, S.; Hollis, C.; Di Stefano, P.

    2016-03-01

    This paper focuses upon the analysis of a complex paleokarstic system recorded within uppermost Triassic peritidal cycles in northwestern Sicily. Besides documenting spectacular karstification at the Triassic/Jurassic boundary, it provides an example of stratabound 'spongy' or 'swiss-cheese' dissolution. On the base of field observations, microfacies analysis, transmitted-light and cathodoluminescence petrography and stable-isotope analyses we put forward an original model for the formation of this peculiar stratabound dissolution. It implies a complex interaction of several controlling factors at the interface between the marine and meteoric diagenetic realms during the relative cyclic oscillations of sea-level. The presence of a fresh water supply from an adjacent emerged area is the key for the periodic formation of a mixing water lens during the relative sea level lowstand that brought about the subaerial exposure of the platform. The resulting dissolution pattern in the subtidal unit of a specific cycle is strongly controlled by the textural features of the sediments. In the case of bioturbated wackestones the 'spongy' or 'swiss-cheese' pattern develops, while in mollusk-rich beds biomoldic porosity occurs. In well-sorted subtidal members, such as algal grainstones, the dissolution originates as randomly distributed vuggy porosity. During periodic flooding of the platform, a new subtidal unit is formed and the dissolution stops as fully marine phreatic conditions are re-established.

  10. Drinking Water

    MedlinePlus

    ... safest water supplies in the world, but drinking water quality can vary from place to place. It depends on the condition of the source water and the treatment it receives. Treatment may include ...

  11. Water Artists.

    ERIC Educational Resources Information Center

    Szekely, George

    2003-01-01

    Discusses how experiences with water provide children with opportunities to be artists. Describes different types of water play for children. Believes that experiences with water introduce children to the principles of painting. (CMK)

  12. Parasites: Water

    MedlinePlus

    ... Tropical Diseases Laboratory Diagnostic Assistance [DPDx] Parasites Home Water Recommend on Facebook Tweet Share Compartir Parasites can live in natural water sources. When outdoors, treat your water before drinking ...

  13. Configuration of water resources for a typical river basin in an arid region of China based on the ecological water requirements (EWRs) of desert riparian vegetation

    NASA Astrophysics Data System (ADS)

    Ling, Hongbo; Guo, Bin; Xu, Hailiang; Fu, Jinyi

    2014-11-01

    Desert riparian vegetation is a natural cover promoting the stability and development of inland river ecosystems in arid regions. Calculating the ecological water requirements (EWRs) of desert riparian vegetation is an important step in achieving reasonable water utilization. Therefore, this study examined the Tarim River, located in an extremely arid region of China, and collected relevant data on hydrology, weather and vegetation using remote sensing. Subsequently, we analyzed the spatial distribution of the desert riparian vegetation in four sections of the Tarim River and calculated the EWR of the desert riparian vegetation using the phreatic evaporation model; additionally, we determined the required runoffs at five hydrologic stations based on the water balance principle. Ultimately, the necessary protection ranges and goals for desert riparian vegetation were established according to the water resource variations in the Tarim River. Our research showed that the total area of desert riparian vegetation along the Tarim River is 16,285.3 km2; this distribution area gradually decreased as the distance from the river increased, and areas varied in the different river sections. The EWRs of desert riparian vegetation from Sections 1 to 5 are 5.698 × 108, 7.585 × 108, 4.900 × 108, 4.101 × 108 m3 and 1.078 × 108 m3, respectively. Therefore, the total EWR of the study region is 23.362 × 108 m3. In terms of the transpiration law of the "unimodal type", the peak value of EWR of natural vegetation occurs in July, and the decreasing trend appears in the other months. Based on the water balance principle, the required runoffs in Alar, Xinquman, Yingbaza, Wusiman and Qiala were determined to be 47.105 × 108, 35.174 × 108, 22.734 × 108, 15.775 × 108 and 7.707 × 108 m3, respectively. According to the water resource frequency and the EWR of the desert riparian vegetation along the Tarim River, we divided the region into three protection ranges: key protection (8

  14. Large-scale regionalization of water table depth in peatlands optimized for greenhouse gas emission upscaling

    NASA Astrophysics Data System (ADS)

    Bechtold, M.; Tiemeyer, B.; Laggner, A.; Leppelt, T.; Frahm, E.; Belting, S.

    2014-09-01

    Fluxes of the three main greenhouse gases (GHG) CO2, CH4 and N2O from peat and other soils with high organic carbon contents are strongly controlled by water table depth. Information about the spatial distribution of water level is thus a crucial input parameter when upscaling GHG emissions to large scales. Here, we investigate the potential of statistical modeling for the regionalization of water levels in organic soils when data covers only a small fraction of the peatlands of the final map. Our study area is Germany. Phreatic water level data from 53 peatlands in Germany were compiled in a new data set comprising 1094 dip wells and 7155 years of data. For each dip well, numerous possible predictor variables were determined using nationally available data sources, which included information about land cover, ditch network, protected areas, topography, peatland characteristics and climatic boundary conditions. We applied boosted regression trees to identify dependencies between predictor variables and dip-well-specific long-term annual mean water level (WL) as well as a transformed form (WLt). The latter was obtained by assuming a hypothetical GHG transfer function and is linearly related to GHG emissions. Our results demonstrate that model calibration on WLt is superior. It increases the explained variance of the water level in the sensitive range for GHG emissions and avoids model bias in subsequent GHG upscaling. The final model explained 45% of WLt variance and was built on nine predictor variables that are based on information about land cover, peatland characteristics, drainage network, topography and climatic boundary conditions. Their individual effects on WLt and the observed parameter interactions provide insight into natural and anthropogenic boundary conditions that control water levels in organic soils. Our study also demonstrates that a large fraction of the observed WLt variance cannot be explained by nationally available predictor variables and

  15. The role of water in cooling ignimbrites

    NASA Astrophysics Data System (ADS)

    Keating, Gordon N.

    2005-04-01

    A summary of observational literature on ignimbrites provides the basis for the development of a two-dimensional numerical model of ignimbrite cooling processes. Factors include emplacement conditions, post-emplacement processes, and the nature and timing of interactions with water during cooling. The model uses the multiphase finite element heat and mass transfer (FEHM) code, which has been enhanced to handle conditions up to 1500 °C. The instantaneous emplacement of a 750 °C ignimbrite with internal gas pressures of up to 0.5 MPa (lithostatic) has a great effect on the variably saturated substrate. A water table present within a few tens of meters of the base of the ignimbrite produces a region of high pressure and temperature that exists for about 20 years, driving vapor upward through the ignimbrite as diffuse flow and in gas escape structures and enhancing cooling at the base of the ignimbrite. Variations in initial gas pressure between atmospheric and lithostatic conditions have little effect on the thermal evolution. The results of the numerical modeling of 20- and 40-m-thick ignimbrites indicate that, even for moderate pore water saturations in the substrate, vaporization and resultant pressurization may exceed lithostatic confining pressures in the upper substrate and basal ignimbrite, and explosive pressure release may occur, resulting in the development of discrete fumarole conduits or phreatic explosions. The likelihood for explosive pressure release appears to be greater when the nominal ignimbrite thickness is on the order of the depth of a buried valley. The pressure buildup is enhanced by the geometry of the ignimbrite-substrate interface, especially at convex corners such as on the edges of a buried valley. The boiling zones at the top and bottom of a cooling ignimbrite involve the development of a heat-pipe, which provides an efficient means of transporting heat from the superheated tephra out tens of meters into the ambient environment. The

  16. Water Purifier

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Floatron water purifier combines two space technologies - ionization for water purification and solar electric power generation. The water purification process involves introducing ionized minerals that kill microorganisms like algae and bacteria. The 12 inch unit floats in a pool while its solar panel collects sunlight that is converted to electricity. The resulting current energizes a specially alloyed mineral electrode below the waterline, causing release of metallic ions into the water. The electrode is the only part that needs replacing, and water purified by the system falls within EPA drinking water standards.

  17. Water tight.

    PubMed

    Postel, S

    1993-01-01

    Many cities worldwide have gone beyond the limits of their water supply. Growing urban populations increase their demand for water, thereby straining local water supplies and requiring engineers to seek our even more distant water sources. It is costly to build and maintain reservoirs, canals, pumping stations, pipes, sewers, and treatment plants. Water supply activities require much energy and chemicals, thereby contributing to environmental pollution. Many cities are beginning to manage the water supply rather than trying to keep up with demand. Pumping ground water for Mexico City's 18 million residents (500,000 people added/year) surpasses natural replenishment by 50% to 80%, resulting in falling water tables and compressed aquifers. Mexico City now ambitiously promotes replacement of conventional toilets with 1.6 gallon toilets (by late 1991, this had saved almost 7.4 billion gallons of water/year). Continued high rural-urban migration and high birth rates could negate any savings, however. Waterloo, Ontario, has also used conservation efforts to manage water demand. These efforts include retrofit kits to make plumbing fixtures more efficient, efficiency standards for plumbing fixtures, and reduction of water use outdoors. San Jose, California, has distributed water savings devices to about 220,000 households with a 90% cooperation rate. Boston, Massachusetts, not only promoted water saving devices but also repaired leaks and had an information campaign. Increasing water rates to actually reflect true costs also leads to water conservation, but not all cities in developing countries use water meters. All households in Edmonton, Alberta, are metered and its water use is 1/2 of that of Calgary, where only some households are metered. Tucson, Arizona, reduced per capita water use 16% by raising water rates and curbing water use on hot days. Bogor, Indonesia, reduced water use almost 30% by increasing water rates. In the US, more and more states are mandating use

  18. Branding water.

    PubMed

    Dolnicar, Sara; Hurlimann, Anna; Grün, Bettina

    2014-06-15

    Branding is a key strategy widely used in commercial marketing to make products more attractive to consumers. With the exception of bottled water, branding has largely not been adopted in the water context although public acceptance is critical to the implementation of water augmentation projects. Based on responses from 6247 study participants collected between 2009 and 2012, this study shows that (1) different kinds of water - specifically recycled water, desalinated water, tap water and rainwater from personal rainwater tanks - are each perceived very differently by the public, (2) external events out of the control of water managers, such as serious droughts or floods, had a minimal effect on people's perceptions of water, (3) perceptions of water were stable over time, and (4) certain water attributes are anticipated to be more effective to use in public communication campaigns aiming at increasing public acceptance for drinking purposes. The results from this study can be used by a diverse range of water stakeholders to increase public acceptance and adoption of water from alternative sources. PMID:24742528

  19. Branding water

    PubMed Central

    Dolnicar, Sara; Hurlimann, Anna; Grün, Bettina

    2014-01-01

    Branding is a key strategy widely used in commercial marketing to make products more attractive to consumers. With the exception of bottled water, branding has largely not been adopted in the water context although public acceptance is critical to the implementation of water augmentation projects. Based on responses from 6247 study participants collected between 2009 and 2012, this study shows that (1) different kinds of water – specifically recycled water, desalinated water, tap water and rainwater from personal rainwater tanks – are each perceived very differently by the public, (2) external events out of the control of water managers, such as serious droughts or floods, had a minimal effect on people's perceptions of water, (3) perceptions of water were stable over time, and (4) certain water attributes are anticipated to be more effective to use in public communication campaigns aiming at increasing public acceptance for drinking purposes. The results from this study can be used by a diverse range of water stakeholders to increase public acceptance and adoption of water from alternative sources. PMID:24742528

  20. Water Underground

    NASA Astrophysics Data System (ADS)

    de Graaf, I. E. M.

    2014-12-01

    The world's largest accessible source of freshwater is hidden underground. However it remains difficult to estimate its volume, and we still cannot answer the question; will there be enough for everybody? In many places of the world groundwater abstraction is unsustainable: more water is used than refilled, leading to decreasing river discharges and declining groundwater levels. It is predicted that for many regions in the world unsustainable water use will increase in the coming decades, due to rising human water use under a changing climate. It would not take long before water shortage causes widespread droughts and the first water war begins. Improving our knowledge about our hidden water is the first step to prevent such large water conflicts. The world's largest aquifers are mapped, but these maps do not mention how much water these aquifers contain or how fast water levels decline. If we can add thickness and geohydrological information to these aquifer maps, we can estimate how much water is stored and its flow direction. Also, data on groundwater age and how fast the aquifer is refilled is needed to predict the impact of human water use and climate change on the groundwater resource. Ultimately, if we can provide this knowledge water conflicts will focus more on a fair distribution instead of absolute amounts of water.

  1. Water resources management in karst aquifers - concepts and modeling approaches

    NASA Astrophysics Data System (ADS)

    Sauter, M.; Schmidt, S.; Abusaada, M.; Reimann, T.; Liedl, R.; Kordilla, J.; Geyer, T.

    2011-12-01

    Water resources management schemes generally imply the availability of a spectrum of various sources of water with a variability of quantity and quality in space and time, and the availability and suitability of storage facilities to cover various demands of water consumers on quantity and quality. Aquifers are generally regarded as suitable reservoirs since large volumes of water can be stored in the subsurface, water is protected from contamination and evaporation and the underground passage assists in the removal of at least some groundwater contaminants. Favorable aquifer properties include high vertical hydraulic conductivities for infiltration, large storage coefficients and not too large hydraulic gradients / conductivities. The latter factors determine the degree of discharge, i.e. loss of groundwater. Considering the above criteria, fractured and karstified aquifers appear to not really fulfill the respective conditions for storage reservoirs. Although infiltration capacity is relatively high, due to low storativity and high hydraulic conductivities, the small quantity of water stored is rapidly discharged. However, for a number of specific conditions, even karst aquifers are suitable for groundwater management schemes. They can be subdivided into active and passive management strategies. Active management options include strategies such as overpumping, i.e. the depletion of the karst water resources below the spring outflow level, the construction of subsurface dams to prevent rapid discharge. Passive management options include the optimal use of the discharging groundwater under natural discharge conditions. System models that include the superposition of the effect of the different compartments soil zone, epikarst, vadose and phreatic zone assist in the optimal usage of the available groundwater resources, while taking into account the different water reservoirs. The elaboration and implementation of groundwater protection schemes employing well

  2. Water resources

    NASA Technical Reports Server (NTRS)

    Simons, D. B.

    1975-01-01

    Applications of remote sensing technology to analysis of watersheds, snow cover, snowmelt, water runoff, soil moisture, land use, playa lakes, flooding, and water quality are summarized. Recommendations are given for further utilization of this technology.

  3. Water Pollution

    ERIC Educational Resources Information Center

    Bowen, H. J. M.

    1975-01-01

    Deals with water pollution in the following categories: a global view, self purification, local pollution, difficulties in chemical analysis, and remedies for water pollution. Emphasizes the extent to which man's activities have modified the cycles of certain elements. (GS)

  4. Water resources

    NASA Technical Reports Server (NTRS)

    Salomonson, V. V.; Rango, A.

    1973-01-01

    The application of ERTS-1 imagery to the conservation and control of water resources is discussed. The effects of exisiting geology and land use in the water shed area on the hydrologic cycle and the general characteristics of runoff are described. The effects of floods, snowcover, and glaciers are analyzed. The use of ERTS-1 imagery to map surface water and wetland areas to provide rapid inventorying over large regions of water bodies is reported.

  5. Water Resources

    NASA Technical Reports Server (NTRS)

    Salomonson, V. V.

    1973-01-01

    Uses of ERTS-1 imagery and data for water resources surveys and management are summarized. Areas discussed are: (1) land use and geology; (2) flood plain and flood inundation mapping; (3) snow cover mapping; (4) glacier observations; (5) data collection systems; (6) surface waters; (7) wetlands mapping; (8) water quality; (9) soil mapping; (10) phreatophyte and riparian vegetation mapping; and (11) evapotranspiration.

  6. Water Ways

    ERIC Educational Resources Information Center

    Jahrling, Peter

    2007-01-01

    In many communities, schools are among the largest facilities and house the highest concentrations of daytime population. They create a huge demand for water. Even in regions with abundant water supplies, an increase in demand stresses local capacity, and water becomes more expensive. However, with the help of innovative products that reduce water…

  7. Optimization of water resources management using SWOT analysis: the case of Zakynthos Island, Ionian Sea, Greece

    NASA Astrophysics Data System (ADS)

    Diamantopoulou, P.; Voudouris, K.

    2008-03-01

    Zakynthos, an island of 408 km2 in the Ionian Sea, is completely dependent on its groundwater resources for fulfilling the demands of the water supplies. The use of groundwater resources has become particularly intensive during the last decades because of the intense urbanization, the tourist development and the irrigated land expansion that took place. The main aquifers are developed in limestones (karstic), sandstones of neogene deposits (confined) and alluvial deposits (phreatic). This paper focuses on the assessment of their hydrogeological characteristics and the groundwater quality. For this investigation, groundwater level measurements, drilling data, pumping tests and chemical analyses of groundwater samples were used. The average annual consumption that is abstracted from the aquifer systems, is 4.9 × 106 m3 year-1. The exploitable groundwater reserves were estimated to be 3.3 × 106 m3 year-1. In the last decades, the total abstractions exceed the natural recharge, due to the tourist development; therefore the aquifer systems are not used safely. The results of chemical analyses showed a deterioration of the groundwater quality. According to the analyses the shallow alluvial aquifer and the confined aquifer are polluted by nitrates at concentrations in excess of 25 mg L-1. High sulphate concentrations might be related to the dissolution of gypsum. Seawater intrusion phenomena are recorded in coastal parts of aquifer systems. The increased Cl- concentrations in karstic aquifer indicate signs of overexploitation. Strengths, weaknesses, opportunities and threats (SWOT) analysis was applied in order to evaluate the SWOT of the groundwater resources. Moreover, some recommendations are made to assist the rational management that aim at improving the sustainability of the groundwater resources of Zakynthos Island.

  8. Water Conditioner

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Aqualizer is designed to cleanse water with minimal use of chemicals by stabilizing the ions in the water. Its applications are both recreational and industrial. A non-electrical passive device, the Aqualizer operates on the principle of catalytic water conditioning. It consists of a stainless steel pipe length with a helical core and is offered in a variety of sizes depending on the quantity of water to be treated. The device is based on NASA silver ionization technology used to purify drinking water aboard the Apollo spacecraft.

  9. Water Filter

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A compact, lightweight electrolytic water sterilizer available through Ambassador Marketing, generates silver ions in concentrations of 50 to 100 parts per billion in water flow system. The silver ions serve as an effective bactericide/deodorizer. Tap water passes through filtering element of silver that has been chemically plated onto activated carbon. The silver inhibits bacterial growth and the activated carbon removes objectionable tastes and odors caused by addition of chlorine and other chemicals in municipal water supply. The three models available are a kitchen unit, a "Tourister" unit for portable use while traveling and a refrigerator unit that attaches to the ice cube water line. A filter will treat 5,000 to 10,000 gallons of water.

  10. Water Jetting

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Hi-Tech Inc., a company which manufactures water jetting equipment, needed a high pressure rotating swivel, but found that available hardware for the system was unsatisfactory. They were assisted by Marshall, which had developed water jetting technology to clean the Space Shuttles. The result was a completely automatic water jetting system which cuts rock and granite and removes concrete. Labor costs have been reduced; dust is suppressed and production has been increased.

  11. Water Purifiers

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Technology developed to purify the water aboard manned spacecraft has led to a number of spinoff applications. One of them is the Ambassador line of bacteriostatic water treatment systems, which employ high grade, high absorption media to inhibit bacteria growth and remove the medicinal taste and odor of chlorine. Company President, Ray Ward, originally became interested in the technology because of the "rusty" taste of his water supply.

  12. Water Filters

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The Aquaspace H2OME Guardian Water Filter, available through Western Water International, Inc., reduces lead in water supplies. The filter is mounted on the faucet and the filter cartridge is placed in the "dead space" between sink and wall. This filter is one of several new filtration devices using the Aquaspace compound filter media, which combines company developed and NASA technology. Aquaspace filters are used in industrial, commercial, residential, and recreational environments as well as by developing nations where water is highly contaminated.

  13. Water underground

    NASA Astrophysics Data System (ADS)

    de Graaf, Inge

    2015-04-01

    The world's largest assessable source of freshwater is hidden underground, but we do not know what is happening to it yet. In many places of the world groundwater is abstracted at unsustainable rates: more water is used than being recharged, leading to decreasing river discharges and declining groundwater levels. It is predicted that for many regions of the world unsustainable water use will increase, due to increasing human water use under changing climate. It would not be long before shortage causes widespread droughts and the first water war begins. Improving our knowledge about our hidden water is the first step to stop this. The world largest aquifers are mapped, but these maps do not mention how much water they contain or how fast water levels decline. If we can add a third dimension to the aquifer maps, so a thickness, and add geohydrological information we can estimate how much water is stored. Also data on groundwater age and how fast it is refilled is needed to predict the impact of human water use and climate change on the groundwater resource.

  14. Virginia's Waters.

    ERIC Educational Resources Information Center

    Sevebeck, Kathryn P.; And Others

    This booklet describes the water resources in Virginia. Main sections included are: (1) "Introduction" (providing a general overview of the richness and diversity of Virginia's water resources both economic and recreational); (2) "River Basins" (illustrating the area drained by nine rivers and their tributaries); (3) "Bays" (including the…

  15. WATER TREATMENT

    DOEpatents

    Pitman, R.W.; Conley, W.R. Jr.

    1962-12-01

    An automated system for adding clarifying chemicals to water in a water treatment plant is described. To a sample of the floc suspension polyacrylamide or similar filter aid chemicals are added, and the sample is then put through a fast filter. The resulting filtrate has the requisite properties for monitoring in an optical turbidimeter to control the automated system. (AEC)

  16. Water tunnels

    NASA Technical Reports Server (NTRS)

    Bjarke, Lisa J.

    1991-01-01

    Some of the uses of water tunnels are demonstrated through the description of the NASA Ames-Dryden Flow Visualization Facility. It is concluded that water tunnels are capable of providing a quick and inexpensive means of flow visualization and can aid in the understanding of complex fluid mechanics phenomena.

  17. Water Pollution

    MedlinePlus

    We all need clean water. People need it to grow crops and to operate factories, and for drinking and recreation. Fish and wildlife depend on ... and phosphorus make algae grow and can turn water green. Bacteria, often from sewage spills, can pollute ...

  18. Water Filters

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A compact, lightweight electrolytic water filter generates silver ions in concentrations of 50 to 100 parts per billion in the water flow system. Silver ions serve as effective bactericide/deodorizers. Ray Ward requested and received from NASA a technical information package on the Shuttle filter, and used it as basis for his own initial development, a home use filter.

  19. Drinking Water

    EPA Science Inventory

    This encyclopedic entry deals with various aspects of microbiology as it relates to drinking water treatment. The use of microbial indicators for assessing fecal contamination is discussed as well as current national drinking water regulations (U.S. EPA) and guidelines proposed ...

  20. Ground water. [Water pollution control

    SciTech Connect

    Costle, D.M.

    1980-09-01

    There is growing evidence that the Nation's ground water is contaminated by a variety of sources. These include unprotected industrial, municipal, and radioactive disposal sites, petroleum exploration and mining activities, agricultural operations such as insecticide spraying, high de-icing salts and others. As of March 1980, more than 8000 chemical tests have been performed on well water, with chlorinated organic solvents found most frequently. Because 100 million Americans may be threatened by unfit drinking water, EPA has developed a new ground water strategy. It will enlist the help of State and local governments who already have programs under way and it will involve broad public debate and participation.

  1. Water Wars

    Energy Science and Technology Software Center (ESTSC)

    2012-09-11

    Sandia National Laboratories and Intel Corporation are cooperating on a project aimed at developing serious games to assist in resource planners in conducting open and participatory projects. Water Wars serves as a prototype game focused on water issues. Water Wars is a multi-player, online role-playing "serious game" combining large-scale simulation (e.g. SimCity), with strategy and interpersonal interaction (e.g. Diplomacy). The game is about water use set in present-day New Mexico. Players enact various stakeholder rolesmore » and compete for water while simultaneously cooperating to prevent environmental collapse. The gamespace utilizes immersive 3D graphics to bring the problem alive. The game integrates Intel's OpenSim visualization engine with Sandia developed agent-based and system dynamics models.« less

  2. Water Wars

    SciTech Connect

    Clark-Casey, Justin

    2012-09-11

    Sandia National Laboratories and Intel Corporation are cooperating on a project aimed at developing serious games to assist in resource planners in conducting open and participatory projects. Water Wars serves as a prototype game focused on water issues. Water Wars is a multi-player, online role-playing "serious game" combining large-scale simulation (e.g. SimCity), with strategy and interpersonal interaction (e.g. Diplomacy). The game is about water use set in present-day New Mexico. Players enact various stakeholder roles and compete for water while simultaneously cooperating to prevent environmental collapse. The gamespace utilizes immersive 3D graphics to bring the problem alive. The game integrates Intel's OpenSim visualization engine with Sandia developed agent-based and system dynamics models.

  3. Drinking Water FAQ

    MedlinePlus

    ... Water & Nutrition Camping, Hiking, Travel Drinking Water Treatment & Sanitation for Backcountry & Travel Use Emergency Disinfection of Drinking ... Drinking Water Healthy Swimming / Recreational Water Global Water, Sanitation, & Hygiene Other Uses of Water Water-related Emergencies & ...

  4. Phreatic flow on sloping soil layers from a finite source: An analytical solution

    SciTech Connect

    Filley, T.H.

    1991-09-01

    Sloping clay layers beneath percolation ponds can cause infiltrating wastewater to pond and move in directions not predicted by vertical infiltration equations. This report presents a method for estimating the potential of wastewater from percolation sumps located over sloping clay layers to interact with nearby groundwater resources. The analytical solution developed is for steady-state conditions and includes a procedure to estimate the time needed to reach steady state. The fundamental assumption used in the mathematical development requires that elevation-head gradients be much larger than pressure-head gradients. A method for testing the validity of this assumption is also included. An example calculation was performed for percolation sumps on the Naval Petroleum Reserve No. 1 in Elk Hills, California. That analysis showed that, under the assumptions used, the sumps may have enabled oil field wastewater to reach groundwater resources within the adjacent San Joaquin Valley. 9 refs., 10 figs.

  5. 2014 Mount Ontake eruption: characteristics of the phreatic eruption as inferred from aerial observations

    NASA Astrophysics Data System (ADS)

    Kaneko, Takayuki; Maeno, Fukashi; Nakada, Setsuya

    2016-05-01

    The sudden eruption of Mount Ontake on September 27, 2014, led to a tragedy that caused more than 60 fatalities including missing persons. In order to mitigate the potential risks posed by similar volcano-related disasters, it is vital to have a clear understanding of the activity status and progression of eruptions. Because the erupted material was largely disturbed while access was strictly prohibited for a month, we analyzed the aerial photographs taken on September 28. The results showed that there were three large vents in the bottom of the Jigokudani valley on September 28. The vent in the center was considered to have been the main vent involved in the eruption, and the vents on either side were considered to have been formed by non-explosive processes. The pyroclastic flows extended approximately 2.5 km along the valley at an average speed of 32 km/h. The absence of burned or fallen trees in this area indicated that the temperatures and destructive forces associated with the pyroclastic flow were both low. The distribution of ballistics was categorized into four zones based on the number of impact craters per unit area, and the furthest impact crater was located 950 m from the vents. Based on ballistic models, the maximum initial velocity of the ejecta was estimated to be 111 m/s. Just after the beginning of the eruption, very few ballistic ejecta had arrived at the summit, even though the eruption plume had risen above the summit, which suggested that a large amount of ballistic ejecta was expelled from the volcano several tens-of-seconds after the beginning of the eruption. This initial period was characterized by the escape of a vapor phase from the vents, which then caused the explosive eruption phase that generated large amounts of ballistic ejecta via sudden decompression of a hydrothermal reservoir.

  6. Descent of tremor source locations before the 2014 phreatic eruption of Ontake volcano, Japan

    NASA Astrophysics Data System (ADS)

    Ogiso, Masashi; Matsubayashi, Hirotoshi; Yamamoto, Tetsuya

    2015-12-01

    On 27 September 2014, Ontake volcano, in central Japan, suddenly erupted without precursory activity. We estimated and tracked the source locations of volcanic tremor associated with the eruption at high temporal resolution, using a method based on the spatial distribution of tremor amplitudes. Although the tremor source locations were not well constrained in depth, their epicenters were well located beneath the erupted crater and the summit. Tremor sources were seen to descend approximately 2 km over a period of several minutes prior to the beginning of the eruption. Detailed analysis of the time series of tremor amplitudes suggests that this descent is a robust feature. Our finding may be an important constraint for modeling the 2014 eruption of Ontake volcano as well as for monitoring activities on this and other volcanoes.

  7. Water Pressure. Water in Africa.

    ERIC Educational Resources Information Center

    Garrett, Carly Sporer

    The Water in Africa Project was realized over a 2-year period by a team of Peace Corps volunteers. As part of an expanded, detailed design, resources were collected from over 90 volunteers serving in African countries, photos and stories were prepared, and standards-based learning units were created for K-12 students. This unit, "Water Pressure,"…

  8. Water Purification

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Vision Catalyst Purifier employs the basic technology developed by NASA to purify water aboard the Apollo spacecraft. However, it also uses an "erosion" technique. The purifier kills bacteria, viruses, and algae by "catalytic corrosion." A cartridge contains a silver-impregnated alumina bed with a large surface area. The catalyst bed converts oxygen in a pool of water to its most oxidative state, killing over 99 percent of the bacteria within five seconds. The cartridge also releases into the pool low levels of ionic silver and copper through a controlled process of erosion. Because the water becomes electrochemically active, no electricity is required.

  9. Water Filters

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Seeking to find a more effective method of filtering potable water that was highly contaminated, Mike Pedersen, founder of Western Water International, learned that NASA had conducted extensive research in methods of purifying water on board manned spacecraft. The key is Aquaspace Compound, a proprietary WWI formula that scientifically blends various types of glandular activated charcoal with other active and inert ingredients. Aquaspace systems remove some substances; chlorine, by atomic adsorption, other types of organic chemicals by mechanical filtration and still others by catalytic reaction. Aquaspace filters are finding wide acceptance in industrial, commercial, residential and recreational applications in the U.S. and abroad.

  10. The role of scenario analysis in water resources management in Yanqi Basin, Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Li, N.; Kinzelbach, W. K.; Li, W.; Dong, X.

    2011-12-01

    With the rapid increase of world population and food demand, the demand for water resources is also increasing. At the same time shifts in rain patterns due to global climate change make the water resources situation more uncertain. A global water crisis can therefore not be excluded. The socio-economic and environmental problems induced by such a water crisis are especially prominent in arid and semiarid regions. The Yanqi Basin in Xinjiang province is a typical case study in China's arid and semi-arid areas, where rainfall is scarce and evaporation is extremely high. Thus its water resources have been under great pressure to satisfy the increasing water demand of agriculture and urban and industrial expansion in the last decades. The development has been accompanied by a number of environmental problems. Yanqi Basin is an important cultivated area which is irrigated by water diverted from rivers. Because of the long-term flood irrigation and an inefficient drainage system, the groundwater level under the cultivated area rose, accelerating the phreatic evaporation and leading to increased soil salinization. Simultaneously, the water quantity and quality of Boston Lake have been impaired in past years because of the decreased river discharge and the increased salt flux contained in the drainage discharge. Thus the ecosystems depending on the inflow to and outflow from the lake suffered. The riverine forests in the downstream area were degraded due to declining groundwater levels, and aquatic life as well as downstream water users had to cope with deteriorating water quality. The big challenge for decision makers in the basin is how to balance the justified requirements of agriculture, industrial development and the ecosystem. In order to provide a scientific basis to the decision making process, a scenario analysis was adopted. Here several scenarios are proposed: the basic scenario, scenario 1, describes the status of the year 2008. A second scenario maximizes the

  11. WATER QUALITY

    EPA Science Inventory

    This manual was develped to provide an overview of microfiltration and ultrafiltration technology for operators, administrators, engineers, scientists, educators, and anyone seeking an introduction to these processes. Chapters on theory, water quality, applications, design, equip...

  12. Water Spout

    NASA Astrophysics Data System (ADS)

    Greenslade, Thomas B.

    2013-02-01

    During the AAPT summer meeting at Creighton University in 2011, Vacek Miglus and I took pictures of early apparatus at the Creighton physics department. The apparatus in the left-hand picture, shown with the spigot closed, appeared to be a liquid-level device: the water level was the same in both the narrow tube and the flaring glass vase. However, when I came back nine months later to give a talk about the apparatus, I realized that it was really an early Bernoulli effect demonstration. In the right-hand picture the spigot is open and water can be seen coming out of the spout. The water level in the narrow tube has fallen appreciably, thus showing that the pressure at this point has decreased, in agreement with the non-zero velocity of the water in the horizontal tube. The device was made ca. 1880 by E. S. Ritchie of Boston, MA. (Photos by Thomas B. Greenslade Jr.)

  13. WATER ANALYSIS

    EPA Science Inventory

    This review covers developments in water analysis from November 1996 to the end of October 1998, as found in the Chemical Abstracts Service CA Selects for gas chromatography, mass spectrometry, inorganic analytical chemistry, and pollution monitoring. In addition, because develop...

  14. Coconut Water

    MedlinePlus

    ... potassium, sodium, and magnesium. Because of this electrolyte composition, there is a lot of interest in using ... dehydration. But some experts suggest that the electrolyte composition in coconut water is not adequate to be ...

  15. Coconut Water

    MedlinePlus

    ... pregnancy and breast-feeding. Stay on the safe side and avoid use. High blood pressure: Coconut water might lower blood pressure. It can increase the effects of medications used to lower blood pressure. Discuss your use ...

  16. Water quality.

    USGS Publications Warehouse

    Steele, T.D.; Stefan, H.G.

    1979-01-01

    Significant contributions in the broad area of water quality over the quadrennium 1975-78 are highlighted. This summare is concerned primarily with physical and chemical aspects of water quality. The diversity of subject areas within the topic heading and the large volume of published research results necessitated the selection of representative contributions. Over 400 references are cited which are believed to be indicative of general trends in research and of the more important developments during this period.- from Authors

  17. Monitoring and Analysis of Transient Pore Water Pressures in Large Suspended Rock Slides near Poschiavo, CH

    NASA Astrophysics Data System (ADS)

    de Palézieux, Larissa; Loew, Simon; Zwahlen, Peter

    2016-04-01

    Many mountain slopes in the Alps exhibit large compound rock slides or Deep Seated Gravitational Slope Deformations. Due to the basal rupture plane geometry and the cumulative displacement magnitude such landslide bodies are often strongly deformed, highly fractured and - at least locally - very permeable. This can lead to high infiltration rates and low phreatic groundwater tables. This is also the situation in the studied mountain slopes southwest of Poschiavo, where large suspended rockslides occur, with very little surface runoff at high elevations, and torrents developing only at the elevation of the basal rupture planes. Below the landslide toes, at altitudes below ca. 1700 m a.s.l., groundwater appears forming spring lines or distributed spring clusters. Within the scope of the design of a hydropower pump storage plant in the Poschiavo valley by Lagobianco SA (Repower AG), numerous cored and deep boreholes (of 50 to 300 m depth) have been drilled along the planned pressure tunnel alignement at elevations ranging from 963 to 2538 m a.s.l. in the years 2010 and 2012. In several boreholes Lugeon and transient pressure tests were executed and pore water pressure sensors installed in short monitoring sections at various depths. Most of these boreholes intersect deep rockslides in crystalline rocks and limestones, showing highly fragmented rock masses and cohesionless cataclastic shear zones of several tens of meters thickness. This study explores these borehole observations in landslides and adjacent stable slopes and links them to the general hydrologic and hydrogeologic framework. The analysis of the pore water pressure data shows significant variability in seasonal trends and short-term events (from snow melt and summer rain storms) and remarkable pressure differences over short horizontal and vertical distances. This reflects rock mass damage within landslide bodies and important sealing horizons at their base. Based on water balances, the estimated effective

  18. ESW 2009: Water, Water Everywhere

    NASA Video Gallery

    Water is all around us, and its importance to nearly every natural process on earth cannot be underestimated. It is vital to life, but it is also tightly coupled to climate, helping to carry heat f...

  19. Total Water Management - slides

    EPA Science Inventory

    Total Water Management (TWM) examines urban water systems in an interconnected manner. It encompasses reducing water demands, increasing water recycling and reuse, creating water supply assets from stormwater management, matching water quality to end-use needs, and achieving envi...

  20. Water availability, water quality water governance: the future ahead

    NASA Astrophysics Data System (ADS)

    Tundisi, J. G.; Matsumura-Tundisi, T.; Ciminelli, V. S.; Barbosa, F. A.

    2015-04-01

    The major challenge for achieving a sustainable future for water resources and water security is the integration of water availability, water quality and water governance. Water is unevenly distributed on Planet Earth and these disparities are cause of several economic, ecological and social differences in the societies of many countries and regions. As a consequence of human misuse, growth of urbanization and soil degradation, water quality is deteriorating continuously. Key components for the maintenance of water quantity and water quality are the vegetation cover of watersheds, reduction of the demand and new water governance that includes integrated management, predictive evaluation of impacts, and ecosystem services. Future research needs are discussed.

  1. Water Conservation and Water Storage

    NASA Astrophysics Data System (ADS)

    Narayanan, M.

    2014-12-01

    Water storage can be a viable part of the solution to water conservation. This means that we should include reservoirs. Regardless, one should evaluate all aspects of water conservation principles. Recent drought in California indicates that there is an urgent need to re-visit the techniques used to maintain the water supply-chain mechanism in the entire state. We all recognize the fact that fish and wildlife depend on the streams, rivers and wetlands for survival. It is a well-known fact that there is an immediate need to provide solid protection to all these resources. Laws and regulations should help meet the needs of natural systems. Farmers may be forced to drilling wells deeper than ever. But, they will be eventually depleting groundwater reserves. Needless to say that birds, fish and wildlife cannot access these groundwater table. California is talking a lot about conservation. Unfortunately, the conservation efforts have not established a strong visible hold. The Environmental Protection Agency has a plan called E2PLAN (Narayanan, 2012). It is EPA's plan for achieving energy and environmental performance, leadership, accountability, and carbon neutrality. In June 2011, the EPA published a comprehensive, multi-year planning document called Strategic Sustainability Performance Plan. The author has previously reported these in detail at the 2012 AGU fall meeting. References: Ziegler, Jay (15 JUNE 2014). The Conversation: Water conservation efforts aren't taking hold, but there are encouraging signs. THE SACRAMENTO BEE. California. Narayanan, Mysore. (2012). The Importance of Water Conservation in the 21st Century. 72nd AGU International Conference. Eos Transactions: American Geophysical Union, Vol. 92, No. 56, Fall Meeting Supplement, 2012. H31I - 1255.http://www.sacbee.com/2014/06/15/6479862/jay-ziegler-water-conservation.html#storylink=cpy

  2. Water Hyacinth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important new reference book entitled the “Encyclopedia of Invasive Introduced Species” is being published by the University of California Press. We were invited to provide a chapter on water hyacinth, which is the world’s worst aquatic weed. In this chapter, we provide information on the origi...

  3. Water Spout

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    2013-01-01

    During the AAPT summer meeting at Creighton University in 2011, Vacek Miglus and I took pictures of early apparatus at the Creighton physics department. The apparatus in the left-hand picture, shown with the spigot closed, appeared to be a liquid-level device: the water level was the same in both the narrow tube and the flaring glass vase.…

  4. Water Filtration

    ERIC Educational Resources Information Center

    Jacobsen, Erica K.

    2004-01-01

    A water filtration column is devised by students using a two-liter plastic bottle containing gravel, sand, and activated charcoal, to test the filtration potential of the column. Results indicate that the filtration column eliminates many of the contaminating materials, but does not kill bacteria.

  5. Artificial groundwater recharge as integral part of a water resources system in a humid environment

    NASA Astrophysics Data System (ADS)

    Kupfersberger, Hans; Stadler, Hermann

    2010-05-01

    In Graz, Austria, artificial groundwater recharge has been operated as an integral part of the drinking water supply system for more than thirty years. About 180 l/s of high quality water from pristine creeks (i.e. no pre-treatment necessary) are infiltrated via sand and lawn basins and infiltration trenches into two phreatic aquifers to sustain the extraction of approximately 400 l/s. The remaining third of drinking water for roughly 300.000 people is provided by a remote supply line from the East alpine karst region Hochschwab. By this threefold model the water supply system is less vulnerable to external conditions. In the early 1980's the infiltration devices were also designed as a hydraulic barrier against riverbank infiltration from the river Mur, which at that time showed seriously impaired water quality due to upstream paper mills. This resulted into high iron and manganese groundwater concentrations which lead to clogging of the pumping wells. These problems have been eliminated in the meantime due to the onsite purification of paper mill effluents and the construction of many waste water treatment plants. The recharge system has recently been thoroughly examined to optimize the operation of groundwater recharge and to provide a basis for further extension. The investigations included (i) field experiments and laboratory analyses to improve the trade off between infiltration rate and elimination capacities of the sand filter basins' top layer, (ii) numerical groundwater modelling to compute the recovery rate of the recharged water, the composition of the origin of the pumped water, emergency scenarios due to the failure of system parts, the transient capture zones of the withdrawal wells and the coordination of recharge and withdrawal and (iii) development of an online monitoring setup combined with a decision support system to guarantee reliable functioning of the entire structure. Additionally, the depreciation, maintenance and operation costs of the

  6. Ground water contamination

    SciTech Connect

    Not Available

    1991-01-01

    This book covers: Ground water contamination and basic concepts of water law; Federal law governing water contamination and remediation; Ground water flow and contaminant migration; Ground water cleanup under CERCLA; Technical methods of remediation and prevention of contamination; Liability for ground water contamination; State constraints on contamination of ground water; Water quantity versus water quality; Prevention of use of contaminated ground water as an alternative to remediation; Economic considerations in liability for ground water contamination; and Contamination, extraction, and injection issues.

  7. Bottled Water and Fluoride

    MedlinePlus

    ... Fluoridation Journal Articles for Community Water Fluoridation Bottled Water Recommend on Facebook Tweet Share Compartir Consumers drink ... questions about bottled water and fluoride. Does bottled water contain fluoride? Bottled water products may contain fluoride, ...

  8. Environmental water requirements of groundwater dependent ecosystems: conflict between nature and man

    NASA Astrophysics Data System (ADS)

    Witczak, S.; Kania, J.; Rozanski, K.; Wachniew, P.; Zurek, A.; Dulinski, M.

    2012-04-01

    new pumping wells has been set up close to the northern border of Niepolomice Forest. There is a growing concern that exploitation of those wells may lead to lowering of water table in the Niepolomice Forest area and, as a consequence, trigger drastic changes of this unique groundwater dependent ecosystem. In order to quantify dynamics of groundwater flow in the area of the Niepolomice Forest and Wielkie Bloto fen, physicochemical parameters and concentrations of environmental tracers (stable isotopes of water, tritium, radiocarbon) were measured in wells located in the recharge area of the Bogucice Sands aquifer and in the newly established wellfield. Also, surface water appearances in the area of Wielkie Bloto fen were investigated. To detect potential discharge of deeper groundwater in the area of Wielkie Bloto fen a dedicated Geoprobe sampling of water from different levels of shallow phreatic aquifer was performed for chemical and isotope analyses. Appropriate modeling runs of the existing 3D flow and transport model of the Bogucice Sands aquifer were also made to investigate possible impact of the newly establish wellfield on the groundwater flow in the Niepolomice Forest area. The chemical and isotope data available to date indicate that in the recharge area, upstream of Wielkie Bloto fen groundwater is relatively young. Presence of appreciable amounts of tritium points to recharge in the past several decades. Radiocarbon content fluctuates between 48 and 65 pmc. In contrast, in the newly established wellfield tritium is absent while radiocarbon content drops to a few pmc. Significant age of groundwater in this area is confirmed by stable isotopes of water revealing characteristic shift towards more negative delta values indicating glacial origin of water. The work was carried out as part of the GENESIS project on groundwater systems (http:/www.thegenesisproject.eu) financed by the European Commission 7FP contract 226536 and the statutory funds of the AGH

  9. Environmental water requirements of groundwater dependent ecosystems: conflict between nature and man

    NASA Astrophysics Data System (ADS)

    Witczak, S.; Kania, J.; Rozanski, K.; Wachniew, P.; Zurek, A.; Dulinski, M.

    2012-04-01

    new pumping wells has been set up close to the northern border of Niepolomice Forest. There is a growing concern that exploitation of those wells may lead to lowering of water table in the Niepolomice Forest area and, as a consequence, trigger drastic changes of this unique groundwater dependent ecosystem. In order to quantify dynamics of groundwater flow in the area of the Niepolomice Forest and Wielkie Bloto fen, physicochemical parameters and concentrations of environmental tracers (stable isotopes of water, tritium, radiocarbon) were measured in wells located in the recharge area of the Bogucice Sands aquifer and in the newly established wellfield. Also, surface water appearances in the area of Wielkie Bloto fen were investigated. To detect potential discharge of deeper groundwater in the area of Wielkie Bloto fen a dedicated Geoprobe sampling of water from different levels of shallow phreatic aquifer was performed for chemical and isotope analyses. Appropriate modeling runs of the existing 3D flow and transport model of the Bogucice Sands aquifer were also made to investigate possible impact of the newly establish wellfield on the groundwater flow in the Niepolomice Forest area. The chemical and isotope data available to date indicate that in the recharge area, upstream of Wielkie Bloto fen groundwater is relatively young. Presence of appreciable amounts of tritium points to recharge in the past several decades. Radiocarbon content fluctuates between 48 and 65 pmc. In contrast, in the newly established wellfield tritium is absent while radiocarbon content drops to a few pmc. Significant age of groundwater in this area is confirmed by stable isotopes of water revealing characteristic shift towards more negative delta values indicating glacial origin of water. The work was carried out as part of the GENESIS project on groundwater systems (http:/www.thegenesisproject.eu) financed by the European Commission 7FP contract 226536 and the statutory funds of the AGH

  10. Water Resources Data, Louisiana, Water Year 2001

    USGS Publications Warehouse

    Goree, B.B.; Lovelace, W.M.; Montgomery, P.A.; Resweber, J.C.; Sasser, D.C., Jr.; Walters, David J.

    2002-01-01

    Water resources data for the 2001 water year for Louisiana consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 71 gaging stations; stage only for 73 gaging stations and 7 lakes; water quality for 66 surface-water stations (including 39 gaging stations) and 92 wells; and water levels for 205 observation wells. Also included are data for 166 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

  11. Water resources data, Louisiana, water year 2003

    USGS Publications Warehouse

    Baumann, Todd; Goree, B.B.; Lovelace, W.M.; Montgomery, P.A.; Resweber, J.C.; Ross, Garron B.; Sasser, D.C., Jr.; Walters, D.J.

    2004-01-01

    Water resources data for the 2003 water year for Louisiana consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 76 gaging stations; stage only for 86 gaging stations and 7 lakes; water quality for 56 surface-water stations (including 44 gaging stations) and 142 wells; and water levels for 313 observation wells. Also included are data for 158 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal and State agencies in Louisiana.

  12. Water Resources Data, Louisiana, Water Year 2000

    USGS Publications Warehouse

    Goree, B.B.; Lovelace, W.M.; Montgomery, P.A.; Resweber, J.C.; Sasser, D.C., Jr.; Walters, David J.

    2001-01-01

    Water resources data for the 2000 water year for Louisiana consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 66 gaging stations; stage only for 70 gaging stations and 7 lakes; water quality for 45 surface-water stations (including 25 gaging stations) and 108 wells; and water levels for 221 observation wells. Also included are data for 204 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

  13. Water resources data, Louisiana, water year 2004

    USGS Publications Warehouse

    Baumann, Todd; Goree, B.B.; Lovelace, W.M.; Montogmery, P.A.; Resweber, J.C.; Ross, Garron B.; Ward, Aub N.; Walters, David J.

    2005-01-01

    Water resources data for the 2004 water year for Louisiana consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 77 gaging stations; stage only for 86 gaging stations and 7 lakes; water quality for 60 surface-water stations (including 42 gaging stations) and 112 wells; and water levels for 304 observation wells. Also included are data for 158 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

  14. Water Resources Data, Louisiana, Water Year 2002

    USGS Publications Warehouse

    Goree, B.B.; Lovelace, W.M.; Montgomery, P.A.; Resweber, J.C.; Labbe, Charles K.; Walters, David J.

    2003-01-01

    Water resources data for the 2002 water year for Louisiana consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 85 gaging stations; stage only for 79 gaging stations and 7 lakes; water quality for 52 surface-water stations (including 40 gaging stations) and 104 wells; and water levels for 300 observation wells. Also included are data for 143 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

  15. Water Wise: A Water Use Handbook.

    ERIC Educational Resources Information Center

    Bureau of Reclamation (Dept. of Interior), Washington, DC.

    This guide for elementary school students deals with the importance of and the uses of water, especially in the western United States. Topics covered include the importance of water as a resource; the need for conservation; water storage through dams and reservoirs; irrigation; the lack of water in the old West; the uses of water for cities and…

  16. Water Purification

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Silver ionization water purification technology was originally developed for Apollo spacecraft. It was later used to cleanse swimming pools and has now been applied to industrial cooling towers and process coolers. Sensible Technologies, Inc. has added two other technologies to the system, which occupies only six square feet. It is manufactured in three capacities, and larger models are custom built on request. The system eliminates scale, corrosion, algae, bacteria and debris, and because of the NASA technology, viruses and waterborne bacteria are also destroyed. Applications include a General Motors cooling tower, amusement parks, ice manufacture and a closed-loop process cooling system.

  17. Water, Ohio's Remarkable Resource.

    ERIC Educational Resources Information Center

    Groves, Carrie J.

    Information on water and water resources in Ohio is presented in seven sections. Water from Ohio streams, water storage, lakes in Ohio, and ground water are discussed in the first section ("Water, A Part of the Earth"). A brief discussion on the ecosystem is provided in the second section ("Water and Life"). Topics discussed in the third section…

  18. Principles of Water Quality

    SciTech Connect

    Waite, T.D.

    1984-01-01

    CONTENTS: Introduction to Water Quality Concepts. Natural Environmental Processes. Toxic Metals as Factors in Water Quality. Refractory Organic Compounds. Nutrients, Productivity, and Eutrophication. Microbes and Water Quality. Thermal Effects and Water Quality. Air Quality. Water Quality Interactions. Introduction to Water Quality Modeling. Water Quality Standards, and Management Approaches.

  19. Be Water Wise.

    ERIC Educational Resources Information Center

    Birch, Sandra K.; Pettus, Alvin M.

    Various topics on water and water conservation are discussed, each general topic followed by a student activity. Topics include: (1) importance of water; (2) water in the environment; (3) getting water to and from homes (making water usable; treating wastewater; on-site systems, including water wells and septic tanks); (4) relationship between…

  20. Water resources data, Arizona, water year 2004

    USGS Publications Warehouse

    Fisk, G.G.; Duet, N.R.; McGuire, E.H.; Angeroth, C.E.; Castillo, N.K.; Smith, C.F.

    2005-01-01

    The USGS Arizona Water Science Center water data report includes records on both surface water and ground water in the State for water year 2004. Specifically, it contains: (1) Discharge records for 206 streamflow-gaging stations and 21 crest-stage, partial-record streamflow stations; (2) stage and (or) content records for 8 lakes and reservoirs; (3) water-quality records for 20 streamflow-gaging stations; (4) ground-water levels and compaction values for 14 stations; and (5) water levels for 18 wells.

  1. Water Sensors

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Mike Morris, former Associate Director of STAC, formed pHish Doctor, Inc. to develop and sell a pH monitor for home aquariums. The monitor, or pHish Doctor, consists of a sensor strip and color chart that continually measures pH levels in an aquarium. This is important because when the level gets too high, ammonia excreted by fish is highly toxic; at low pH, bacteria that normally break down waste products stop functioning. Sales have run into the tens of thousands of dollars. A NASA Tech Brief Technical Support Package later led to a salt water version of the system and a DoE Small Business Innovation Research (SBIR) grant for development of a sensor for sea buoys. The company, now known as Ocean Optics, Inc., is currently studying the effects of carbon dioxide buildup as well as exploring other commercial applications for the fiber optic sensor.

  2. Water resources data, Nebraska, water year 2004

    USGS Publications Warehouse

    Hitch, D. E., (compiler); Soensken, P.J.; Sebree, S.K.; Wilson, K.E.; Walczyk, V.C.; Drudik, R.A.; Miller, J.D.; Hull, S.H.

    2005-01-01

    The Nebraska water resources data report for water year 2004 includes records of stage, discharge, and water quality of streams; water elevation and/or contents of lakes and reservoirs; and water levels and quality of ground water in wells. This report contains records of stream stage for 3 stations; stream discharge for 101 continuous and 5 crest-stage gaging stations, and 6 miscellaneous sites; stream water quality for 7 gaging stations and 40 miscellaneous sites; water elevation and/or contents for 2 lakes and 1 reservoir; ground-water levels for 74 observation wells; and ground-water quality for 200 wells. These data represent that part of the National Water Data System collected in and near Nebraska by the U.S. Geological Survey and cooperating Federal, State, and local agencies.

  3. Water Resources Data, Nebraska, Water Year 2003

    USGS Publications Warehouse

    Hitch, D.E.; Hull, S.H.; Walczyk, V.C.; Miller, J.D.; Drudik, R.A.

    2004-01-01

    The Nebraska water resources data report for water year 2003 includes records of stage, discharge, and water quality of streams; water elevation and/or contents of lakes and reservoirs; and water levels and quality of ground water in wells. This report contains records of stream stage for 3 stations; stream discharge for 103 continuous and 5 crest-stage gaging stations, and 5 miscellaneous sites; stream water quality for 14 gaging stations and 5 miscellaneous sites; water elevation and/or contents for 2 lakes and 1 reservoir; ground-water levels for 40 observation wells; and ground-water quality for 132 wells. These data represent that part of the National Water Data System collected in and near Nebraska by the U.S. Geological Survey and cooperating local, State, and Federal agencies.

  4. Water resources data, Alaska, water year 2004

    USGS Publications Warehouse

    Meyer, D.F.; Best, H.R.; Host, R.H.; Murray, R.P.; Solin, G.L.

    2005-01-01

    Water resources data for the 2004 water year for Alaska consist of records of stage, discharge, and water quality of streams; stages of lakes; and water levels and water quality of ground water. This volume contains records for water discharge at 115 gaging stations; stage or contents only at 3 gaging stations; water quality at 39 gaging stations; and water levels for 26 observation wells. Also included are data for 55 crest-stage partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. Some data collected during 2004 will be published in subsequent reports. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Alaska.

  5. Lead and tap water

    MedlinePlus

    Water contaminated with lead ... The Environmental Protection Agency (EPA) monitors drinking water and requires water suppliers to produce annual water quality reports. These reports, which include information about lead amounts, are available to consumers. For ...

  6. Lead and tap water

    MedlinePlus

    Water contaminated with lead ... The Environmental Protection Agency (EPA) monitors drinking water in the United States. It requires water suppliers to produce annual water quality reports. These reports include information about lead amounts, and they ...

  7. Why Do Eyes Water?

    MedlinePlus

    ... Help White House Lunch Recipes Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  8. Water chemistry and poultry processing water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the influences of water chemistry on the quality of process water used in immersion chillers. During commercial poultry processing the bird carcasses come in direct contact with process water during washing and chilling operations. Contamination of the process water with bacteria...

  9. Water Resources Data, Arizona, Water Year 2003

    USGS Publications Warehouse

    Fisk, G.G.; Duet, N.R.; Evans, D.W.; Angeroth, C.E.; Castillo, N.K.; Longsworth, S.A.

    2004-01-01

    The Arizona District water data report includes records on both surface water and ground water in the State for water year 2003. Specifically, it contains: (1) discharge records for 203 streamflow-gaging stations, for 29 crest-stage, partial-record streamflow stations, and 50 miscellaneous sites; (2) stage and (or) content only records for 9 lakes and reservoirs; (3) water-quality records for 29 streamflow-gaging stations; (4) ground-water levels and compaction values for 14 stations; and (5) water levels for 19 wells.

  10. Testing the Waters.

    ERIC Educational Resources Information Center

    Finks, Mason

    1993-01-01

    Provides information about home drinking water treatment systems to address concerns about the safety and quality of drinking water. Discusses water testing, filtration, product options and selection, water testing resources, water treatment device guidelines, water analysis terminology, and laboratory selection. (MCO)

  11. Everyone into the Water!

    ERIC Educational Resources Information Center

    Hennessey, Christina L.

    2007-01-01

    As the days grow longer and warmer with the approach of summer, everyone's thoughts turn to the outdoors and the clear blue of water sports. While recreational choices range from in-the-water activities like water polo to under-the-water sports like free diving, and on-the-water diversions like water skiing, this article focuses on print, video,…

  12. DISINFECTION OF WATER: DRINKING WATER, RECREATIONAL WATER, AND WASTEWATER

    EPA Science Inventory

    This chapter describes and categorizes the methodology used for disinfection of drinking water, recreational water and wastewater including wastewater sludges. It largely is a literature summary and references articles covering the years of 1939 through 1999, with a few reference...

  13. Geological Implications on the Different Products of Submarine Volcanism in Sangihe Waters : View from the Rov (Remotely Operated Vehicles)

    NASA Astrophysics Data System (ADS)

    Priyadi, B.; Basuki, N.; Abidin, H.; Permana, H.; Handayani, L.; Wirasantosa, S.; Nganro, N.; Djamaluddin, R.; Ch. Kusuma, L.; Ratna Setyawidati, N.; Makarim, S.; Solihudin, T.

    2010-12-01

    Index Satal 2010, a joint marine research of Indonesia - USA, was realized in June-August 2010 to explore the deep sea of the Sangihe - Talaud Waters of Indonesia. This research was conducted by RV Baruna Jaya-4 and RV Okeanos Explorer of NOAA. Beside conducting multi beam imagery, RV Okeanos Explorer produced photos and video of the selected sites through high definition cameras mounted on an ROV operated from onboard RV Okeanos Explorer. The following discussion were based on ROV observation concerning the occurrence of volcanic products in the dive sites. Two submarine volcanoes (Naung and Kawio Barat), indicate various textures of submarine volcanic products from which magmatic composition and eruption types can be inferred. Lava is mostly observed around Kawio Barat and reflecting slightly coarse grained, thick and less structured, and in some spots flow textures could be observed especially in rough morphology. The overlying lavas show finer grain size with relatively shinny surface and darker color and supposedly having less contents of silica as it forms pillow and sheeting joint structures. The rock composition is presumably basaltic and is related with the subduction systems of the Sangihe arc. The coarser lavas might be more andesitic in composition, hence they are originated from the more differentiated magma chamber. This phenomenon indicates a change of magmatic composition from more differentiated magma to the less differentiated one. Geologically, this observation may indicate new formation of magma that may be related with the increasing intensity of subduction activity. Volcanic products around Naung are observed as pyroclastic covers on basaltic lavas. Pyroclastics present as lapilli deposit in light to dark brown colors forming stratification of 2 cm to 30 cm thick and unconsolidated clastic materials. The occurrence of pebble-size fragments of igneous rocks associated with pyroclastics indicate a phreatic to phreato-magmatic explosions of the

  14. Smart Water: Energy-Water Optimization in Drinking Water Systems

    EPA Science Inventory

    This project aims to develop and commercialize a Smart Water Platform – Sensor-based Data-driven Energy-Water Optimization technology in drinking water systems. The key technological advances rely on cross-platform data acquisition and management system, model-based real-time sys...

  15. Water, Water Everywhere: Phase Diagrams of Ordinary Water Substance

    ERIC Educational Resources Information Center

    Glasser, L.

    2004-01-01

    The full phase diagram of water in the form of a graphical representation of the three-dimensional (3D) PVT diagram using authentic data is presented. An interesting controversy regarding the phase behavior of water was the much-touted proposal of a solid phase of water, polywater, supposedly stable under atmospheric conditions.

  16. Water Resources Data, Utah, Water Year 1989

    USGS Publications Warehouse

    ReMillard, M.D.; Herbert, L.R.; Sandberg, G.W.; Birdwell, G.A.

    1990-01-01

    Water resources data for the 1989 water year for Utah consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water quality of ground water. This report contains discharge records for 185 gaging stations; stage and contents for 22 lakes and reservoirs; water quality for 21 hydrologic stations and 217 wells; miscellaneous temperature measurements and field determinations for 147 stations; and water levels for 29 observations wells. Additional water data were collected at various sites not involved in the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Utah.

  17. Water resources data, Kentucky, water year 2004

    USGS Publications Warehouse

    McClain, Dennis L.; Moses, Clifford R.; Darnell, Roy S.

    2005-01-01

    Water resources data for the 2004 water year for Kentucky consist of records of stage, discharge, and water-quality of streams and lakes; and water levels of wells. This report includes daily discharge records for 131 stream-stations. It also includes water-quality data for 15 stations sampled at regular intervals, continuous temperature at 7 stations, and continuous water-quality at 11 stations. Ground-water levels are published for 8 recording and 22 partial record sites. Precipitation data at a regular interval are published for two sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Kentucky.

  18. Water Resources Data, Kentucky, Water Year 2003

    USGS Publications Warehouse

    McClain, D.L.; Brown, A.C.; Moses, C.R.; Darnell, R.S.

    2004-01-01

    Water resources data for the 2003 water year for Kentucky consist of records of stage, discharge, and water quality of streams and lakes; and water levels of wells. This report includes daily discharge records for 127 stream-gaging stations. It also includes water-quality data for eight stations sampled at regular intervals, continuous temperature at seven stations, and continuous water quality at nine stations. Ground-water levels are published for 8 recording and 16 partial-record sites. Precipitation data at regular intervals are published for one site. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurement and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Kentucky.

  19. Water Resources Data, Kentucky, Water Year 2002

    USGS Publications Warehouse

    McClain, D.L.; Byrd, F.D.; Brown, A.C.; Moses, C.R.

    2003-01-01

    Water resources data for the 2002 water year for Kentucky consist of records of stage, discharge, and water quality of streams and lakes; and water levels of wells. This report includes daily discharge records for 120 streamgaging stations. It also includes water-quality data for eight stations sampled at regular intervals, continuous temperature at four stations, and continuous water quality at nine stations. Ground-water levels are published for 8 recording and 23 partial-record sites. Precipitation data at regular intervals are published for one site. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurement and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Kentucky.

  20. Quasi 3D modeling of water flow and solute transport in vadose zone and groundwater

    NASA Astrophysics Data System (ADS)

    Yakirevich, A.; Kuznetsov, M.; Weisbrod, N.; Pachepsky, Y. A.

    2013-12-01

    The complexity of subsurface flow systems calls for a variety of concepts leading to the multiplicity of simplified flow models. One commonly used simplification is based on the assumption that lateral flow and transport in unsaturated zone is insignificant unless the capillary fringe is involved. In such cases the flow and transport in the unsaturated zone above groundwater level can be simulated as a 1D phenomenon, whereas through groundwater they are viewed as 2D or 3D phenomena. A new approach for a numerical scheme for 3D variably saturated flow and transport is presented. A Quasi-3D approach allows representing flow in the 'vadose zone - aquifer' system by a series of 1D Richards' equations solved in variably-saturated zone and by 3D-saturated flow equation in groundwater (modified MODFLOW code). The 1D and 3D equations are coupled at the phreatic surface in a way that aquifer replenishment is calculated using the Richards' equation, and solving for the moving water table does not require definition of the specific yield parameter. The 3D advection-dispersion equation is solved in the entire domain by the MT3D code. Using implicit finite differences approximation to couple processes in the vadose zone and groundwater provides mass conservation and increase of computational efficiency. The above model was applied to simulate the impact of irrigation on groundwater salinity in the Alto Piura aquifer (Northern Peru). Studies on changing groundwater quality in arid and semi-arid lands show that irrigation return flow is one of the major factors contributing to aquifer salinization. Existing mathematical models do not account explicitly for the solute recycling during irrigation on a daily scale. Recycling occurs throughout the unsaturated and saturated zones, as function of the solute mass extracted from pumping wells. Salt concentration in irrigation water is calculated at each time step as a function of concentration of both surface water and groundwater

  1. Water Pollution. Project COMPSEP.

    ERIC Educational Resources Information Center

    Lantz, H. B., Jr.

    This is an introductory program on water pollution. Examined are the cause and effect relationships of water pollution, sources of water pollution, and possible alternatives to effect solutions from our water pollution problems. Included is background information on water pollution, a glossary of pollution terminology, a script for a slide script…

  2. Global monthly water stress: 1. Water balance and water availability

    NASA Astrophysics Data System (ADS)

    van Beek, L. P. H.; Wada, Yoshihide; Bierkens, Marc F. P.

    2011-07-01

    Surface fresh water (i.e., blue water) is a vital and indispensable resource for human water use in the agricultural, industrial, and domestic sectors. In this paper, global water availability is calculated by forcing the global hydrological model PCR-GLOBWB with daily global meteorological fields for the period 1958-2001. To represent blue water availability, a prognostic reservoir operation scheme was included in order to produce monthly time series of global river discharge modulated by reservoir operations. To specify green water availability for irrigated areas, actual transpiration from the model was used. Thus, the computed water availability reflects the climatic variability over 1958-2001 and is contrasted against the monthly water demand using the year 2000 as a benchmark in the companion paper. As the water that is withdrawn to meet demand directly interferes with blue water availability along the drainage network, this paper evaluates model performance for three regimes reflecting different degrees of human interference: natural discharge, discharge regulated by reservoirs, and modified discharge. In the case of modified discharge, the net blue water demand for the year 2000 is subtracted directly from the regulated discharge, taking water demand equal to consumptive water use. Results show that model simulations of monthly river discharge compare well with observations from most of the large rivers. Exceptions are basins subject to large extractions for irrigation purposes, where simulated discharge exceeds the observations even when water demand is taken into account. Including the prognostic reservoir operation scheme results in mixed performance, with a poorer approximation of peak flows but with a marginally better simulation of low flows and persistence. A comparison of simulated actual evapotranspiration with that from the ERA-40 reanalysis as a proxy for observed rates shows similar patterns over nonirrigated areas but substantial deviations

  3. Water in diet

    MedlinePlus

    ... the cells and organs need water to function. Water serves as a lubricant. It makes up saliva and the fluids surrounding the joints. Water regulates the body temperature through perspiration . It also ...

  4. Ground Water Remediation Technologies

    EPA Science Inventory

    The USEPA's Ground Water and Ecosystems Restoration Division (GWERD) conducts research and provides technical assistance to support the development of strategies and technologies to protect and restore ground water, surface water, and ecosystems impacted by man-made and natural...

  5. Water safety and drowning

    MedlinePlus

    ... among people of all ages. Learning and practicing water safety is important to prevent drowning accidents. ... Water safety tips for all ages include: Learn CPR Never swim alone Never dive into water unless ...

  6. Aging Water Infrastructure

    EPA Science Inventory

    The Aging Water Infrastructure (AWI) research program is part of EPA’s larger effort called the Sustainable Water Infrastructure (SI) initiative. The SI initiative brings together drinking water and wastewater utility managers; trade associations; local watershed protection organ...

  7. Jumping of water striders on water

    NASA Astrophysics Data System (ADS)

    Yang, Eunjin; Son, Jaehak; Jablonski, Piotr; Kim, Ho-Young

    2012-11-01

    Small insects such as water striders, springtails, fishing spiders freely move on water by adopting various modes of locomotion, such as rowing, galloping, jumping and meniscus-climbing. As the physics of jumping have not yet been fully understood among those ways of semi-aquatic propulsion, here we present the results of a combined experimental and theoretical investigation of the dynamics of water striders leaping off water. We first image and analyze the trajectories of the legs and body of jumping water striders of three different species with a high-speed camera. We then theoretically compute the forces acting on the body by considering the capillary interaction between the flexible legs and deforming water meniscus. Our theory enables us to predict the maximum take-off speed for given leg lengths. The experimental measurements suggest that the water striders drive their legs near the optimal speed to gain the maximum take-off speed.

  8. Water Quality of Hills Water, Supply Water and RO Water Machine at Ulu Yam Selangor

    NASA Astrophysics Data System (ADS)

    Ngadiman, N.; ‘I Bahari, N.; Kaamin, M.; Hamid, N. B.; Mokhtar, M.; Sahat, S.

    2016-07-01

    The rapid development resulted in the deterioration of the quality of drinking water in Malaysia. Recognizing the importance of water quality, new alternatives for drinking water such as mineral water processing from reverse osmosis (RO) machine become more popular. Hence, the demand for mineral water, natural spring water or water from the hills or mountains rose lately. More consumers believed the quality of these spring water better than other source of drinking water. However, the quality of all the drinking water sources is to meet the required quality standard. Therefore, this paper aims to measure the quality of the waters from hills, from RO machine and the water supply in Ulu Yam, Selangor Batang Kali, Malaysia. The water quality was determined based on following parameters: ammoniacal nitrogen (NH3), iron (Fe), turbidity (NTU) and pH. The results show that the water from hills has better quality compared to water supply and water from RO machine. The value of NH3 ranged from 0.03 mg/L- 0.67 mg/L; Fe was from 0.03mg/L - 0.12 mg/L, turbidity at 0.42 NTU - 0.88 NTU and pH is at 6.60 - 0.71. Based on the studied parameters, all three types of water are fit for drinking and have met the required national drinking water quality standard.

  9. Recreational Water Illness (RWI): MRSA

    MedlinePlus

    ... Work: Healthy Swimming Policy & Recommendations Fast Facts Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global ... Unlikely to be Spread Through Swimming Pools. Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global ...

  10. Healthy Swimming/Recreational Water

    MedlinePlus

    ... Index of Water-Related Topics Featured Partners Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global WASH Other Uses of Water WASH-related Emergencies & Outbreaks Water, Sanitation, & Environmentally-related ...

  11. Kunming experiences water shortage

    SciTech Connect

    Sun Chaozhen

    1983-07-17

    This article examines a Chinese city's measures to plan the water supply and conserve water, and to ensure a regular supply of water to drink and use in production. The Kunming city government called an emergency mobilization meeting on water conservation. Kunming has suffered from a severe lack of rainfall over the past 2 years. In order to overcome the present water shortage, it was decided to publicize the importance of planning the water supply and water conservation; to set limits on the amount of water used and to crack down on large consumers of water; and to make further rational and scientific uses of water. The Kunming government has proposed saving 20% of the water now being consumed.

  12. 2010 Water & Aqueous Solutions

    SciTech Connect

    Dor Ben-Amotz

    2010-08-13

    Water covers more than two thirds of the surface of the Earth and about the same fraction of water forms the total mass of a human body. Since the early days of our civilization water has also been in the focus of technological developments, starting from converting it to wine to more modern achievements. The meeting will focus on recent advances in experimental, theoretical, and computational understanding of the behavior of the most important and fascinating liquid in a variety of situations and applications. The emphasis will be less on water properties per se than on water as a medium in which fundamental dynamic and reactive processes take place. In the following sessions, speakers will discuss the latest breakthroughs in unraveling these processes at the molecular level: Water in Solutions; Water in Motion I and II; Water in Biology I and II; Water in the Environment I and II; Water in Confined Geometries and Water in Discussion (keynote lecture and poster winners presentations).

  13. Water-heating dehumidifier

    DOEpatents

    Tomlinson, John J.

    2006-04-18

    A water-heating dehumidifier includes a refrigerant loop including a compressor, at least one condenser, an expansion device and an evaporator including an evaporator fan. The condenser includes a water inlet and a water outlet for flowing water therethrough or proximate thereto, or is affixed to the tank or immersed into the tank to effect water heating without flowing water. The immersed condenser design includes a self-insulated capillary tube expansion device for simplicity and high efficiency. In a water heating mode air is drawn by the evaporator fan across the evaporator to produce cooled and dehumidified air and heat taken from the air is absorbed by the refrigerant at the evaporator and is pumped to the condenser, where water is heated. When the tank of water heater is full of hot water or a humidistat set point is reached, the water-heating dehumidifier can switch to run as a dehumidifier.

  14. Confined Water as Model of Supercooled Water.

    PubMed

    Cerveny, Silvina; Mallamace, Francesco; Swenson, Jan; Vogel, Michael; Xu, Limei

    2016-07-13

    Water in confined geometries has obvious relevance in biology, geology, and other areas where the material properties are strongly dependent on the amount and behavior of water in these types of materials. Another reason to restrict the size of water domains by different types of geometrical confinements has been the possibility to study the structural and dynamical behavior of water in the deeply supercooled regime (e.g., 150-230 K at ambient pressure), where bulk water immediately crystallizes to ice. In this paper we give a short review of studies with this particular goal. However, from these studies it is also clear that the interpretations of the experimental data are far from evident. Therefore, we present three main interpretations to explain the experimental data, and we discuss their advantages and disadvantages. Unfortunately, none of the proposed scenarios is able to predict all the observations for supercooled and glassy bulk water, indicating that either the structural and dynamical alterations of confined water are too severe to make predictions for bulk water or the differences in how the studied water has been prepared (applied cooling rate, resulting density of the water, etc.) are too large for direct and quantitative comparisons. PMID:26940794

  15. Water treatment technology for produced water.

    PubMed

    Szép, Angéla; Kohlheb, Robert

    2010-01-01

    Large amounts of produced water are generated during oil and gas production. Produced water, as it is known in the oil industry, is briny fluid trapped in the rock of oil reservoirs. The objective of this study was to test produced waters from a Montana USA oilfield using a mobile station to design a plant to cost efficiently treat the produced water for agricultural irrigation. We used combined physical and chemical treatment of produced water in order to comply with reuse and discharge limits. This mobile station consists of three stages: pretreatments, membrane filtration and post treatment. Two spiral-wound membrane units were employed and the rejections of various constituents were examined. The performance of two membranes, 20 kDa weight cut-off (MWCO) ultrafiltration and a polyamide-composite reverse osmosis membrane was investigated. The mobile station effectively decreased conductivity by 98%, COD by 100% and the SAR by 2.15 mgeqv(0.5) in the produced water tested in this study. Cost analysis showed that the treatment cost of produced water is less expensive than to dispose of it by injection and this treated water may be of great value in water-poor regions. We can conclude that the mobile station provided a viable and cost-effective result to beneficial use of produced water. PMID:21076224

  16. Sustainability and Water

    NASA Astrophysics Data System (ADS)

    Sharma, Virender A.

    2009-07-01

    World's population numbered 6.1 billion in 2000 and is currently increasing at a rate of about 77 million per year. By 2025, the estimated total world population will be of the order of 7.9 billion. Water plays a central role in any systematic appraisal of life sustaining requirements. Water also strongly influences economic activity (both production and consumption) and social roles. Fresh water is distributed unevenly, with nearly 500 million people suffering water stress or serious water scarcity. Two-thirds of the world's population may be subjected to moderate to high water stress in 2025. It is estimated that by 2025, the total water use will increase by to 40%. The resources of water supply and recreation may also come under stress due to changes in climate such as water balance for Lake Balaton (Hungary). Conventional urban water systems such as water supply, wastewater, and storm water management are also currently going through stress and require major rethinking. To maintain urban water systems efficiently in the future, a flexibility approach will allow incorporation of new technologies and adaptation to external changes (for example society or climate change). Because water is an essential resource for sustaining health, both the quantity and quality of available water supplies must be improved. The impact of water quality on human health is severe, with millions of deaths each year from water-borne diseases, while water pollution and aquatic ecosystem destruction continue to rise. Additionally, emerging contaminants such as endocrine disruptor chemicals (EDCs), pharmaceuticals, and toxins in the water body are also of a great concern. An innovative ferrate(VI) technology is highly effective in removing these contaminants in water. This technology is green, which addresses problems associated with chlorination and ozonation for treating pollutants present in water and wastewater. Examples are presented to demonstrate the applications of ferrate

  17. Water footprint of Ghana

    NASA Astrophysics Data System (ADS)

    Debrah, E. R.; Odai, S. N.; Annor, F. O.; Adjei, K. A.; van der Zaag, P.

    2009-04-01

    Water is used in almost all human endeavour. Unlike oil, water does not have a substitute. There are many factors that affect the water consumption pattern of people. These include climatic condition, income level and agricultural practices among others. The water footprint concept has been developed in order to have an indicator of water use in relation to its consumption by people. The water footprint of a country is defined as the volume of water needed for the production of the goods and services consumed by the inhabitants of the country (Chapagain and Hoekstra, 2008). Due to the bulky nature of water, it is not in its raw state a tradable commodity though it could be traded through the exchange of goods and services from one point to the other. Closely linked to the water footprint concept is the virtual water concept. Virtual water can be defined as the volume of water required to produce a commodity or service (Chapagain and Hoekstra, 2008 and Allan, 1999). The international trade of these commodities implies flows of virtual water over large distances. The water footprint of a nation can therefore be assessed by quantifying the use of domestic water resources, taking out the virtual water flow that leaves the country and adding the virtual water flow that enters the country to it. This research focuses on the assessment and analysis of the water footprints of Ghana considering only the consumptive component of the water footprint. In addition to livestock, 13 crops were considered, 4 of which were cash crops. Data was analysed for the year 2001 to 2005 The most recent framework for the analysis of water footprint is offered by Chapagain and Hoekstra. This was adopted for the study. The water footprint calculations show that the water footprint of Ghana is about 20011 Gm³/yr. Base on this the average water footprint of a Ghanaian is 823 m³/cap/yr. Not only agricultural crops but also other products require water for their manufacture, aluminium being a

  18. Cryptosporidium: A Guide to Water Filters

    MedlinePlus

    ... Healthy Water Healthy Swimming/Recreational Water Global Water, Sanitation, & Hygiene (WASH) Other Uses of Water Water-related ... Healthy Water Healthy Swimming/Recreational Water Global Water, Sanitation, & Hygiene (WASH) Other Uses of Water Water-related ...

  19. Waves and Water Beetles

    ERIC Educational Resources Information Center

    Tucker, Vance A.

    1971-01-01

    Capillary and gravity water waves are related to the position, wavelength, and velocity of an object in flowing water. Water patterns are presented for ships and the whirling beetle with an explanation of how the design affects the objects velocity and the observed water wavelengths. (DS)

  20. Domestic wash water reclamation

    NASA Technical Reports Server (NTRS)

    Hall, J. B., Jr.; Batten, C. E.; Wilkins, J. R.

    1974-01-01

    System consists of filtration unit, reverse-osmosis module, tanks, pumps, plumbing, and various gauges, meters, and valves. After water is used in washing machine or shower, it is collected in holding tank. Water is pumped through series of five particulate filters. Pressure tank supplies processed water to commode water closet.

  1. Hold the Water

    ERIC Educational Resources Information Center

    Kravitz, Robert; Reichardt, Klaus

    2006-01-01

    Many facilities are considering no-water urinals because they are regarded as an effective way to conserve water. Water must be pumped by electricity, some estimate that as much as $300 per year per urinal can be saved in utility costs. The installation of no-water urinals can help buildings achieve credits toward Leadership in Energy and…

  2. Alabama Water Use, 2005

    USGS Publications Warehouse

    Hutson, Susan S.; Littlepage, Thomas M.; Harper, Michael J.; Tinney, James O.

    2009-01-01

    Water is one of Alabama's most precious natural resources. It is a vital component of human existence and essential to the overall quality of life. Wise stewardship of this valuable resource depends on a continuing assessment of water availability and water use. Population growth in many parts of the State has resulted in increased competition for available water resources. This competition includes offstream uses, such as residential, agricultural, and industrial, and instream uses for maintenance of species habitat and diversity, navigation, power generation, recreation, and water quality. Accurate water-use information is required for sound management decisions within this competitive framework and is necessary for a more comprehensive understanding of the link between water use, water supply, and overall water availability. A study of water use during 2005 was conducted by the U.S. Geological Survey (USGS), in cooperation with the Alabama Department of Economic and Community Affairs, Office of Water Resources, Water Management Branch (ADECA-OWR), to provide water-use data for local and State water managers. The results of the study about the amount of water used, how it was used, and where it was used in Alabama have been published in 'Estimated use of water in Alabama in 2005' by Hutson and others, 2009, and is accessible on the Web at http://pubs.usgs.gov/sir/2009/5163 and available upon request as a CD-ROM through USGS and ADECA-OWR.

  3. Salt, Water, and Athletes.

    ERIC Educational Resources Information Center

    Smith, Nathan J.

    Good nutrition for athletes demands plenty of water, since water is essential to such vital functions as muscle reactions. Dehydration can result from jet travel as well as from exercise and heat, making it a danger to traveling athletic teams. To avoid dehydration, water needs should be monitored by frequent weighing, and a clean water supply…

  4. Save Our Water Resources.

    ERIC Educational Resources Information Center

    Bromley, Albert W.

    The purpose of this booklet, developed as part of Project SOAR (Save Our American Resources), is to give Scout leaders some facts about the world's resources, the sources of water pollution, and how people can help in obtaining solutions. Among the topics discussed are the world's water resources, the water cycle, water quality, sources of water…

  5. Exploratorium: Exploring Water.

    ERIC Educational Resources Information Center

    Brand, Judith, Ed.

    2001-01-01

    This issue of Exploratorium focuses on water and its varied uses in our environment. Articles include: (1) "Adventures with Water" (Eric Muller); (2) "Water: The Liquid of Life" (Karen E. Kalumuck); (3) "Water-Drop Projector" (Gorazd Planinsic); (4) "Waterways and Means" (Pearl Tesler); (5) "Explore Natural Phenomena in the Museum--and Just…

  6. Lifting China's water spell.

    PubMed

    Guan, Dabo; Hubacek, Klaus; Tillotson, Martin; Zhao, Hongyan; Liu, Weidong; Liu, Zhu; Liang, Sai

    2014-10-01

    China is a country with significant but unevenly distributed water resources. The water stressed North stays in contrast to the water abundant and polluted South defining China's current water environment. In this paper we use the latest available data sets and adopt structural decomposition analysis for the years 1992 to 2007 to investigate the driving forces behind the emerging water crisis in China. We employ four water indicators in China, that is, freshwater consumption, discharge of COD (chemical oxygen demand) in effluent water, cumulative COD and dilution water requirements for cumulative pollution, to investigate the driving forces behind the emerging crisis. The paper finds water intensity improvements can effectively offset annual freshwater consumption and COD discharge driven by per capita GDP growth, but that it had failed to eliminate cumulative pollution in water bodies. Between 1992 and 2007, 225 million tones of COD accumulated in Chinese water bodies, which would require 3.2-8.5 trillion m(3) freshwater, depending on the water quality of the recipient water bodies to dilute pollution to a minimum reusable standard. Cumulative water pollution is a key driver to pollution induced water scarcity across China. In addition, urban household consumption, export of goods and services, and infrastructure investment are the main factors contributing to accumulated water pollution since 2000. PMID:25226569

  7. Water and Something Else.

    ERIC Educational Resources Information Center

    Hougendobler, Nancy

    Prepared for middle or intermediate grades, this student booklet provides a study of water--the location of major oceans and rivers; the relationship of ancient civilizations to bodies of water; active metals found in sea water; chemical concentrations in water and their effects on marine life; and the concepts of evaporation, transpiration,…

  8. Potable water taste enhancement

    NASA Technical Reports Server (NTRS)

    1974-01-01

    An analysis was conducted to determine the causes of and remedies for the unpalatability of potable water in manned spacecraft. Criteria and specifications for palatable water were established and a quantitative laboratory analysis technique was developed for determinig the amounts of volatile organics in good tasting water. Prototype spacecraft water reclamation systems are evaluated in terms of the essential palatability factors.

  9. Can Water Mean Health?

    ERIC Educational Resources Information Center

    Black, Maggie, Ed.

    1983-01-01

    This issue of UNICEF News explores the theme of connections between water and health in developing countries. The introductory article discusses prospects for improving health through water projects during the International Drinking Water Supply and Sanitation Decade (1981-90). Subsequent articles focus on (1) effects of a piped water supply on…

  10. WATER QUALITY CRITERIA DOCUMENTS

    EPA Science Inventory

    Background

    Water quality standards and criteria are the foundation for a wide range of programs under the Clean Water Act. Specifically, under section 304(a)(1) of the Clean Water Act it requires EPA to develop criteria for water quality that accurately re...

  11. Potable water supply

    NASA Technical Reports Server (NTRS)

    Sauer, R. L.; Calley, D. J.

    1975-01-01

    The history and evolution of the Apollo potable water system is reviewed. Its operation in the space environment and in the spacecraft is described. Its performance is evaluated. The Apollo potable water system satisfied the dual purpose of providing metabolic water for the crewmen and water for spacecraft cooling.

  12. New Folklore about Water.

    ERIC Educational Resources Information Center

    LeMaire, Peter; Waiveris, Charles

    1995-01-01

    Describes experiments designed to investigate the cooling rate of microwave-boiled water as compared to that of stove-boiled water. Concludes that within experimental limits, microwave-boiled water and stove-boiled water cool at the same rate. (JRH)

  13. Water policy sinkhole

    SciTech Connect

    Anderson, T.L.

    1983-10-01

    The pollution of both surface and ground waters and the withdrawal of ground water will present the US with a major water-quality and -supply problem unless changes are made in how we use water. If water is priced at market value instead of relying on federal subsidies, price signals could alter consumption patterns. Other changes that could help are removing restrictions on water transfers and allowing private ownership of waterways and appropriable rights to ground water. These steps, it is felt, would encourage responsible consumption and allocations. (DCK)

  14. Leptospirosis from water sources

    PubMed Central

    Wynwood, Sarah Jane; Graham, Glenn Charles; Weier, Steven Lance; Collet, Trudi Anne; McKay, David Brian; Craig, Scott Benjamin

    2014-01-01

    Leptospirosis outbreaks have been associated with many common water events including water consumption, water sports, environmental disasters, and occupational exposure. The ability of leptospires to survive in moist environments makes them a high-risk agent for infection following contact with any contaminated water source. Water treatment processes reduce the likelihood of leptospirosis or other microbial agents causing infection provided that they do not malfunction and the distribution networks are maintained. Notably, there are many differences in water treatment systems around the world, particularly between developing and developed countries. Detection of leptospirosis in water samples is uncommonly performed by molecular methods. PMID:25348115

  15. Wash water recovery system

    NASA Technical Reports Server (NTRS)

    Deckman, G.; Rousseau, J. (Editor)

    1973-01-01

    The Wash Water Recovery System (WWRS) is intended for use in processing shower bath water onboard a spacecraft. The WWRS utilizes flash evaporation, vapor compression, and pyrolytic reaction to process the wash water to allow recovery of potable water. Wash water flashing and foaming characteristics, are evaluated physical properties, of concentrated wash water are determined, and a long term feasibility study on the system is performed. In addition, a computer analysis of the system and a detail design of a 10 lb/hr vortex-type water vapor compressor were completed. The computer analysis also sized remaining system components on the basis of the new vortex compressor design.

  16. Vadose zone water fluxmeter

    DOEpatents

    Faybishenko, Boris A.

    2005-10-25

    A Vadose Zone Water Fluxmeter (WFM) or Direct Measurement WFM provides direct measurement of unsaturated water flow in the vadose zone. The fluxmeter is a cylindrical device that fits in a borehole or can be installed near the surface, or in pits, or in pile structures. The fluxmeter is primarily a combination of tensiometers and a porous element or plate in a water cell that is used for water injection or extraction under field conditions. The same water pressure measured outside and inside of the soil sheltered by the lower cylinder of the fluxmeter indicates that the water flux through the lower cylinder is similar to the water flux in the surrounding soil. The fluxmeter provides direct measurement of the water flow rate in the unsaturated soils and then determines the water flux, i.e. the water flow rate per unit area.

  17. Water Resources Data, Mississippi, Water Year 2002

    USGS Publications Warehouse

    Morris, F., III; Turnipseed, D.P.; Storm, J.B.

    2003-01-01

    Water resources data for the 2002 water year for Mississippi consist of records of surface water and ground water in the State. Specifically, it contains: (1) Discharge records for 91 streamflow-gaging stations, stage records for 22 of these gaging stations, discharge records for 91 partial-record stations or miscellaneous streamflow sites, including 13 flood hydrograph partial-record stations, 78 crest-stage partial-record stations, and 0 special study and miscellaneous sites; (2) stage only at 9 gaging stations; (3) water-quality records for 13 streamflow-gaging stations, 7 stage-only stations, and 3 water-quality monitor stations, 0 partial-record stations or miscellaneous sites, 97 short-term study sites, and 39 wells; and (4) water-level records for 18 observation wells. Records obtained from water-resources investigations are also included in special sections of the report. These data represent that part of the National Water Data System operated by the U.S. Geological Survey, and cooperating local, State, and Federal agencies in Mississippi.

  18. Ground water and energy

    SciTech Connect

    Not Available

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  19. Water, something peculiar.

    USGS Publications Warehouse

    Van Hylckama, T. E. A.

    1979-01-01

    Some chemical and physical properties of water are discussed and compared with those of other fluids. For instance, the boiling point is much higher than one would expect considering the molecular weight of water. The heat capacity is also much higher but the viscosity is not. The dielectric constant is exceptionally high. These and other properties of water can be explained by the geometry of the water molecule and the structure of water or ice. -Author

  20. Urban Water '88

    NASA Astrophysics Data System (ADS)

    Zuidena, Floris C.; Hoogart, Hans

    The Symposium on Hydrological Processes and Water Management in Urban Areas (Urban Water '88) was held in Duisburg, West Germany, and The Netherlands, April 24-29, 1988. Six themes were discussed during the 3-day conference and 2-day study tour: urban hydrological cycle, functions and uses of water, concepts of urban drainage and flood protection, effects of urbanization on surface and groundwater, and the role of water in city planning and integrated water management in urban areas.

  1. Solvation in supercritical water

    SciTech Connect

    Cochran, H.D. ); Cummings, P.T.; Karaborni, S. . Dept. of Chemical Engineering)

    1991-01-01

    The aim of this work is to determine the solvation structure in supercritical water composed with that in ambient water and in simple supercritical solvents. Molecular dynamics studies have been undertaken of systems that model ionic sodium and chloride, atomic argon, and molecular methanol in supercritical aqueous solutions using the simple point charge model of Berendsen for water. Because of the strong interactions between water and ions, ionic solutes are strongly attractive in supercritical water, forming large clusters of water molecules around each ion. Methanol is found to be a weakly-attractive solute in supercritical water. The cluster of excess water molecules surrounding a dissolved ion or polar molecule in supercritical aqueous solutions is comparable to the solvent clusters surrounding attractive solutes in simple supercritical fluids. Likewise, the deficit of water molecules surrounding a dissolved argon atom in supercritical aqueous solutions is comparable to that surrounding repulsive solutes in simple supercritical fluids. The number of hydrogen bonds per water molecule in supercritical water was found to be about one third the number in ambient water. The number of hydrogen bonds per water molecule surrounding a central particle in supercritical water was only mildly affected by the identify of the central particle--atom, molecule, or ion. These results should be helpful in developing a qualitative understanding of important processes that occur in supercritical water. 29 refs., 6 figs.

  2. Water microbiology. Bacterial pathogens and water.

    PubMed

    Cabral, João P S

    2010-10-01

    Water is essential to life, but many people do not have access to clean and safe drinking water and many die of waterborne bacterial infections. In this review a general characterization of the most important bacterial diseases transmitted through water-cholera, typhoid fever and bacillary dysentery-is presented, focusing on the biology and ecology of the causal agents and on the diseases' characteristics and their life cycles in the environment. The importance of pathogenic Escherichia coli strains and emerging pathogens in drinking water-transmitted diseases is also briefly discussed. Microbiological water analysis is mainly based on the concept of fecal indicator bacteria. The main bacteria present in human and animal feces (focusing on their behavior in their hosts and in the environment) and the most important fecal indicator bacteria are presented and discussed (focusing on the advantages and limitations of their use as markers). Important sources of bacterial fecal pollution of environmental waters are also briefly indicated. In the last topic it is discussed which indicators of fecal pollution should be used in current drinking water microbiological analysis. It was concluded that safe drinking water for all is one of the major challenges of the 21st century and that microbiological control of drinking water should be the norm everywhere. Routine basic microbiological analysis of drinking water should be carried out by assaying the presence of Escherichia coli by culture methods. Whenever financial resources are available, fecal coliform determinations should be complemented with the quantification of enterococci. More studies are needed in order to check if ammonia is reliable for a preliminary screening for emergency fecal pollution outbreaks. Financial resources should be devoted to a better understanding of the ecology and behavior of human and animal fecal bacteria in environmental waters. PMID:21139855

  3. PREFACE: Water at interfaces Water at interfaces

    NASA Astrophysics Data System (ADS)

    Gallo, P.; Rovere, M.

    2010-07-01

    This special issue is devoted to illustrating important aspects and significant results in the field of modeling and simulation of water at interfaces with solutes or with confining substrates, focusing on a range of temperatures from ambient to supercooled. Understanding the behavior of water, in contact with different substrates and/or in solutions, is of pivotal importance for a wide range of applications in physics, chemistry and biochemistry. Simulations of confined and/or interfacial water are also relevant for testing how different its behavior is with respect to bulk water. Simulations and modeling in this field are of particular importance when studying supercooled regions where water shows anomalous properties. These considerations motivated the organization of a workshop at CECAM in the summer of 2009 which aimed to bring together scientists working with computer simulations on the properties of water in various environments with different methodologies. In this special issue, we collected a variety of interesting contributions from some of the speakers of the workshop. We have roughly classified the contributions into four groups. The papers of the first group address the properties of interfacial and confined water upon supercooling in an effort to understand the relation with anomalous behavior of supercooled bulk water. The second group deals with the specific problem of solvation. The next group deals with water in different environments by considering problems of great importance in technological and biological applications. Finally, the last group deals with quantum mechanical calculations related to the role of water in chemical processes. The first group of papers is introduced by the general paper of Stanley et al. The authors discuss recent progress in understanding the anomalies of water in bulk, nanoconfined, and biological environments. They present evidence that liquid water may display 'polymorphism', a property that can be present in

  4. More water: better health.

    PubMed

    Cairncross, S

    1997-01-01

    This article discusses the role of clean water in preventing fecal-oral transmission of infections, skin and eye diseases, water-based diseases, and insect vector diseases. Improvements to water quality are not sufficient to reduce infection. There is a need to educate people about appropriate hygiene and hand washing with soap and cleanliness of storage and eating utensils. Access to clean water is also important. Access to water reduces the household burden for women and children in time and effort. Households farthest from a supply of clean water would benefit the most from access to a clean water supply in time, effort, and money saved. The World Bank found that just the time saved in water collection was sufficient to justify house connections to a public supply of water. Most people would gladly pay for a water supply to be connected to their house. Free water at standpipes does not interfere with the demand for house connections. It was found that when water sources were shifted to locations closer than 1 km, the shift resulted in an increase in the amount of water used. When round-trip water collection takes about 30 minutes, level of use remains constant. When a water supply is moved to within a few yards of the house or piped indoors, use doubles or triples. Fecal contamination of water causes high rates of diarrheal disease, which kills over 3 million children per year. Diseases, such as cholera and typhoid fever, are transmitted through water-fecal links as well as contaminated food, fingers, utensils, and even clothes. More water available in the home would prevent women from using a corner of their sari to wipe dishes, wipe faces, and wipe a child's bottom. Large storage tanks do not prevent the presence of parasitic worms or insect vectors in the water supply. PMID:12321042

  5. Paying for water.

    PubMed

    Middleton, J; Saunders, P

    1997-03-01

    Water has been taken for granted as an essential public health need since the Victorian sanitary revolution. Water has come back on to the public health agenda in the United Kingdom because of recent policy changes and their untoward environmental and social impacts; along with water privatization and tough new environmental directives, there have been serious water pollution incidents, water shortages, water debt and disconnection. Along with concern about protecting individual rights to a clean safe water supply, there is concern about the ability of national water resources to meet all our communities' needs, without unacceptable environmental damage. A national plan is needed for the conservation of water and protection of water resources and the environment; adequate central funds are needed to see that this happens. There should be greater emphasis on local water management and a key role for local authorities; there should be fair pricing, protection of water supplies for the poorest and most vulnerable, and a ban on water disconnection to domestic users, on public health grounds. More research is needed into the potential adverse health impact of people on prepayment meters disconnecting themselves. There is a place for water metering as the most rapidly deliverable means of controlling peak demand, reducing overall consumption and avoiding a large-scale environmentally damaging solution to supply more water. However, control of leakage offers the largest potential saving and is the most cost-effective means to protect existing water supply. We question whether private water companies, geared to maximizing profit and share dividends, can deliver a national plan for the protection and management of water resources, for the good of the environment and future generations. The public health lobby must become more actively engaged in the debate about the supply, protection and price of our most precious public health asset-water. PMID:9138226

  6. OVERVIEW OF USEPA'S WATER SUPPLY & WATER RESOURCES DIVISION PROGRAM

    EPA Science Inventory

    The United States Environmental Protection Agency's (USEPA) Water Supply and Water Resources Division (WSWRD) conducts a wide range of research on regulated and unregulated contaminants in drinking water, water distribution systems, homeland security, source water protection, and...

  7. Drainage water management for water quality protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land drainage has been central to the development of North America since colonial times. Increasingly, agricultural drainage is being targeted as a conduit for pollution, particularly nutrient pollution. The export of agricultural drainage water and associated pollutants to surface water can be mana...

  8. Water-Borne Illnesses. Water in Africa.

    ERIC Educational Resources Information Center

    Garrett, Carly Sporer

    The Water in Africa Project was realized over a 2-year period by a team of Peace Corps volunteers. As part of an expanded, detailed design, resources were collected from over 90 volunteers serving in African countries, photos and stories were prepared, and standards-based learning units were created for K-12 students. This unit, "Water-Borne…

  9. Water resources data, Kentucky. Water year 1991

    SciTech Connect

    McClain, D.L.; Byrd, F.D.; Brown, A.C.

    1991-12-31

    Water resources data for the 1991 water year for Kentucky consist of records of stage, discharge, and water quality of streams and lakes; and water-levels of wells. This report includes daily discharge records for 115 stream-gaging stations. It also includes water-quality data for 38 stations sampled at regular intervals. Also published are 13 daily temperature and 8 specific conductance records, and 85 miscellaneous temperature and specific conductance determinations for the gaging stations. Suspended-sediment data for 12 stations (of which 5 are daily) are also published. Ground-water levels are published for 23 recording and 117 partial sites. Precipitation data at a regular interval is published for 1 site. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurement and analyses. These data represent that part of the National Water Data System operated by the US Geological Survey and cooperation State and Federal agencies in Kentucky.

  10. Water recovery in space.

    PubMed

    Tamponnet, C; Savage, C J; Amblard, P; Lasserre, J C; Personne, J C; Germain, J C

    1999-03-01

    In the absence of recycling, water represents over 90% of the life-support consumables for a manned spacecraft. In addition, over 90% of the waste water generated can be classified as moderately or slightly contaminated (e.g. shower water, condensate from the air-conditioning system, etc.). The ability to recover potable water from moderately contaminated waste water hence enables significant savings to be made in resupply costs. A development model of such a water-recovery system, based on membrane technology has been produced and tested using "real waste water" based on used shower water Results indicate some 95% recovery of potable water meeting ESA standards, with total elimination of microbial contaminants such as bacteria, spores and viruses. PMID:11725802