bluuebunny/crossref_metadata_2025_split huggingface dataset:
A SURVEY OF HYDROLOGY COURSE CONTENT IN NORTH AMERICAN UNIVERSITIES1
Authors: Groves James R. , Moody David W. 
Published: June 2007

ABSTRACT: This report presents the results of a survey of hydrology faculties of colleges and universities in the United States and Canada. Information is presented on topics covered in classes, allocation of class periods to individual topics, textbooks, prerequisites, computer use, and accreditation categories for hydrology courses offered by engineering departments. Hydrology courses generally require courses in fluid mechanics, mathematics, statistics, and computer science as prerequisites. Topics that receive the largest allocation of time in both introductory and advanced courses include rainfall‐runoff relations, the hydrologic cycle, routing and open channel flow, and statistics. Advanced courses place greater emphasis on watershed models than do the introductory courses. Hydrology courses at both levels allocate the smallest amounts of time to snow hydrology ground‐water hydrology, and “other topics.” Very few courses include field or experimental work. In a discipline where computer modeling is a major tool, this lack of field and data‐collection experience may lead students to underestimate the uncertainties associated with data used to calibrate models and the modeling results themselves.Survey responses on hydrology courses taught in departments other than civil engineering were too few to permit detailed analysis. Most of these courses spend approximately two‐thirds of available class time on the same topics as presented in engineering hydrology courses. The balance of class time is spent on topics that emphasize the specialized interest of the particular discipline, such as soil physics and soil moisture in agricultural engineering.
EFFECTS OF AGRICULTURAL NUTRIENT MANAGEMENT ON NITROGEN FATE AND TRANSPORT IN LANCASTER COUNTY PENNSYLVANIA1
Authors: Hall David W. , Risser Dennis W. 
Published: June 2007

ABSTRACT: Nitrogen inputs to, and outputs from, a 55‐acre site in Lancaster County, Pennsylvania, were estimated to determine the pathways and relative magnitude of loads of nitrogen entering and leaving the site, and to compare the loads of nitrogen before and after the implementation of nutrient management.Inputs of nitrogen to the site were manure fertilizer, commercial fertilizer, nitrogen in precipitation, and nitrogen in ground‐water inflow; and these sources averaged 93, 4, 2, and 1 percent of average annual nitrogen additions, respectively. Outputs of nitrogen from the site were nitrogen in harvested crops, loads of nitrogen in surface runoff, volatilization of nitrogen, and loads of nitrogen in ground‐water discharge, which averaged 37, less than 1, 25, and 38 percent of average annual nitrogen removals from the site, respectively. Virtually all of the nitrogen leaving the site that was not removed in harvested crops or by volatilization was discharged in the ground water.Applications of manure and fertilizer nitrogen to 47.5 acres of cropped fields decreased about 33 percent, from an average of 22,700 pounds per year (480 pounds per acre per year) before nutrient management to 15,175 pounds of nitrogen per year (320 pounds per acre per year) after the implementation of nutrient management practices. Nitrogen loads in ground‐water discharged from the site decreased about 30 percent, from an average of 292 pounds of nitrogen per million gallons of ground water before nutrient management to an average of 203 pounds of nitrogen per million gallons as a result of the decreased manure and commercial fertilizer applications. Reductions in manure and commercial fertilizer applications caused a reduction of approximately 11,000 pounds (3,760 pounds per year; 70 pounds per acre per year) in the load of nitrogen discharged in ground water from the 55‐acre site during the three‐year period 1987–1990.
HYDROGEOLOGY AND PATHS OF FLOW IN THE CARBONATE BEDROCK AQUIFER, NORTHWESTERN INDIANA1
Authors: Arihood Leslie D. 
Published: June 2007

ABSTRACT: The U.S. Geological Survey (USGS) is assessing the ground‐water resources of the carbonate bedrock aquifers in Indiana and Ohio as part of their Regional Aquifer Systems Analysis program. Part of this assessment includes the determination of unknown aspects of the hydraulic characteristics, boundaries, and flow paths of the carbonate aquifer. To accomplish this, the USGS drilled three wells through the carbonate aquifer near the Kankakee River in northwestern Indiana. Geophysical logs were used to help determine depths and thicknesses for testing and to help describe geology at the three wells. Packer tests were used to determine direction of ground‐water flow and to provide data for an analysis of the distribution of transmissivity in the carbonate aquifer.Transmissivity of the carbonates is associated with two physical characteristics of the rocks: fractures and interconnected porosity. Almost all of the transmissivity is derived from horizontal fracturing; however, only a few of the fractures present in the carbonate are transmissive. Some transmissivity is associated with a zone of fossiliferous, vuggy dolomite, which yields water from the rock matrix. Most of the transmissivity is associated with large fractures and solution crevices in the upper 30 feet of the bedrock; less transmissivity is associated with the deeper vuggy reef material, even where extensively fractured. Transmissivity of individual fractures and fossiliferous zones ranges from 300 to 27,000 feet squared per day. The aquifer bottom is defined by a lack of transmissive fractures and an increased shale content near the contact of the Silurian and Ordovician sections.Water‐level data from the three wells indicate that flow is horizontal at well site 1 north of the Kankakee River, upward at well site 2 near the river, and downward at well site 3 south of the river. Most of the flow occurs in the upper part of the carbonate bedrock where fracturing and solution‐enlarged crevices are most developed. Water levels indicate the the Kankakee River is a hydrologic boundary for the regional carbonate bedrock aquifer.
THE FLOOD HAZARD AND DYNAMICS OF THE URBAN RESIDENTIAL LAND MARKET1
Authors: Tobin Graham A. , Montz Burrell E. 
Published: June 2007

ABSTRACT: Literature on the flood hazard/residential land market relationship is full of contradictory findings, many of which are counter‐intuitive to the belief that flooding has a negative impact on house prices. This research advances a conceptual framework through which these relationships might be re‐examined. Based on the expected utility model, the theoretical framework integrates the economic notion of capitalization with spatial and temporal characteristics of the flood hazard.Four communities with different flood regimes are used to test the effect of flooding on the residential real estate market. Results show that, (1) there is an identifiable relationship between characteristics of the flood hazard and changes in house values; (2) the length of the recovery period is dependent on characteristics and expectations of flooding, attributes of the real estate market, and availability of capital to fuel recovery; and (3) dynamics of the urban market and spatial extent of the flood hazard influence these relationships. Further research is now necessary to examine these findings under different spatial, temporal, hydrological, and socio‐economic conditions.
MEASURING THE VALUE OF POTABLE WATER IN PARTIALLY MONETIZED RURAL ECONOMIES1
Authors: Hardner Jared J. 
Published: June 2007

ABSTRACT:A pilot study was conducted to test the potential of the Contingent Valuation Methodology (CVM) to reveal the value of non‐market goods in a partially monetized subsistence economy. CVM was used to estimate the willingness to pay, in the form of labor, for potable drinking water in a rural river‐based community located in the Esmeraldas state of northwest Ecuador. Surveys were administered by personal interviews with families living along the waterways of the Santiago river system who used river water for cooking, drinking, washing, and waste disposal.The mean willingness to pay represented over 23 percent of real income, or 1.4 days per week for a period of one year. Results of multiple regression analysis identified the history of water‐related health problems and the number of working adults in a household as significant determinants of willingness to pay.Using a non‐monetary, rather than a monetary measure of willingness to pay may provide a more accurate representation of value in a subsistence economy where the use of money is limited. The potential for CVM to measure the benefits of non‐market goods in rural developing regions whose economies are only partially monetized is demonstrated.
NUTRIENT CONCENTRATIONS IN WASTEWATER TREATMENT PLANT EFFLUENTS, SOUTH PLATTE RWER BASIN1
Authors: Pocernich Matthew , Litke David W. 
Published: June 2007

ABSTRACT: Accurate data about nutrient concentrations in wastewater treatment plant effluents are needed for river basin water‐quality studies. As part of the U.S. Geological Survey's National Water‐Quality Assessment Program in the South Platte River Basin, nutrient data were requested from 31 wastewater‐treatment plants located in the basin. This article describes the types of nutrient data available from the plants, examines the variability of effluent nutrient concentrations, and discusses methods for estimation of nutrient concentrations where data are lacking.Ammonia was monitored at 88 percent of the plants, nitrite plus nitrate was monitored at 40 percent of the plants, and organic nitrogen and phosphorus were monitored at less than 25 percent of the plants. Median total nitrogen concentrations and median total phosphorus concentrations were small compared to typical literature estimates for wastewater‐treatment plants with secondary treatment. Nutrient concentrations in effluent from wastewater‐treatment plants varied widely between and within plants. For example, ammonia concentrations varied as much as 5 mg/L during a day, as much as 10 mg/L from day to day, and as much as 30 mg/L from summer to winter within a plant. In the South Platte River Basin, estimates of median annual ammonia and nitrite plus nitrate concentrations can be improved based on plant processes; and nitrite plus nitrate and organic nitrogen concentrations can be estimated based on ammonia concentrations. However, to avoid large estimation errors, more complete nutrient data from wastewater‐treatment plants are needed for integration into river basin water quality studies. The paucity of data hinders attempts to evaluate the relative importance of point source and nonpoint source nutrient loadings to rivers.
ANALYSIS OF PUMPING TESTS: SIGNIFICANCE OF WELL DIAMETER, PARTIAL PENETRATION, AND NOISE1
Authors: Heidari Manoutchehr , Ghiassi Kamran , Mehnert Edward 
Published: June 2007

ABSTRACT: The nonlinear least squares (NLS) method was applied to pumping and recovery aquifer test data in confined and unconfined aquifers with finite diameter and partially penetrating pumping wells, and with partially penetrating piezometers or observation wells. It was demonstrated that noiseless and moderately noisy drawdown data from observation points located less than two saturated thicknesses of the aquifer from the pumping well produced an exact or acceptable set of parameters when the diameter of the pumping well was included in the analysis. The accuracy of the estimated parameters, particularly that of specific storage, decreased with increases in the noise level in the observed drawdown data. With consideration of the well radii, the noiseless drawdown data from the pumping well in an unconfined aquifer produced good estimates of horizontal and vertical hydraulic conductivities and specific yield, but the estimated specific storage was unacceptable. When noisy data from the pumping well were used, an acceptable set of parameters was not obtained. Further experiments with noisy drawdown data in an unconfined aquifer revealed that when the well diameter was included in the analysis, hydraulic conductivity, specific yield and vertical hydraulic conductivity may be estimated rather effectively from piezometers located over a range of distances from the pumping well. Estimation of specific storage became less reliable for piezometers located at distances greater than the initial saturated thickness of the aquifer.Application of the NLS to field pumping and recovery data from a confined aquifer showed that the estimated parameters from the two tests were in good agreement only when the well diameter was included in the analysis. Without consideration of well radii, the estimated values of hydraulic conductivity from the pumping and recovery tests were off by a factor of four.
A HANDY DECISION SUPPORT SYSTEM FOR RESERVOIR OPERATION IN TAIWAN1
Authors: Huang Wen‐Cheng , Yang Fu‐Ti 
Published: June 2007

ABSTRACT:A user‐friendly decision support system (DSS) for long‐term reservoir operation has been introduced with an eye to practical use. The system can assist reservoir managers to work out applicable rules for real‐time reservoir operation. The DSS model has already been applied experimentally to the main reservoirs in Taiwan with success. In this study, Tsengwen Reservoir, the largest reservoir in Taiwan, was chosen to test the applicability of the model. The simulation results show that the DSS is not only well suited to long‐term reservoir operation, but also very easily applied. A handy DSS was designed for user‐friendly computer interaction with Microsoft Excel in the Windows system. Users can survey on‐line reservoir operation with a browser on the World Wide Web (WWW). The uniform resource locator of the DSS is http://wrm.hre.ntou.edu.tw.. So users may easily access the DSS via the Internet.
A SIPHON GAGE FOR MONITORING SURFACE‐WATER LEVELS1
Authors: McCobb Timothy D. , LeBlanc Denis R. , Socolow Roy S. 
Published: June 2007

ABSTRACTA device that uses a siphon tube to establish a hydraulic connection between the bottom of an onshore standpipe and a point at the bottom of a water body was designed and tested for monitoring surface‐water levels. Water is added to the standpipe to a level sufficient to drive a complete slug of water through the siphoning tube and to flush all air out of the system. The water levels in the standpipe and the water body equilibrate and provide a measurable static water surface in the standpipe. The siphon gage was designed to allow quick and accurate year‐round measurements with minimal maintenance. Currently available devices for monitoring surface‐water levels commonly involve time‐consuming and costly installation and surveying, and the movement of reference points and the presence of ice cover in cold regions cause discontinuity and inaccuracy in the data collected. Installation and field testing of a siphon gage using 0.75‐in‐diameter polyethylene tubing at Ashumet Pond in Falmouth, Massachusetts, demonstrated that the siphon gage can provide long‐term data with a field effort and accuracy equivalent to measurement of ground‐water levels at an observation well.
OXYGEN SAG EQUATION FOR THREE‐HALVES ORDER BOD REACTION1
Authors: Adrian Donald Dean , Sanders Thomas G. , Roider Emerald M. 
Published: June 2007

ABSTRACTSeveral published BOD data sets are examined to show that approximately half of them are described best in the least squares sense by treating the BOD equation as being of the three‐halves order instead of first order. A dissolved oxygen (DO) sag equation for a stream is developed in which the BOD is described as a three‐halves order reaction. The time when the minimum DO concentration occurs is calculated numerically. The DO sag model applied to example problems shows that an increase in the BOD reaction rate constant results in a smaller minimum DO concentration and a decrease in the time to reach the minimum DO.
BRACKISH GROUNDWATER DESALINATION: A COMMUNITY'S SOLUTION TO WATER SUPPLY AND AQUIFER PROTECTION1
Authors: Blair David A. , Spronz William D. , Ryan Keith W. 
Published: June 2007

ABSTRACTThe City of Cape May, New Jersey, draws its primary water supply from the Cohansey Aquifer, a unit serving residential, community, and industrial users throughout the Coastal Plain. By the year 2000, projected population growth will impose a peak water demand beyond available supplies. In addition, regional over‐pumping threatens the Cohansey with saltwater intrusion, placing the city wells at risk by 1998. In the early‐to mid 1990s, three broad categories of water‐supply alternatives were evaluated by regional, state, and federal agencies — additional pumping from the Cohansey, conjunctive use of the Cohansey with other aquifers, and desalination of brackish groundwater. An approach was adopted in 1996 which derives up to 2 MGD from desalination of brackish groundwater, with the remaining peak demand satisfied by short‐term pumpage from existing wells in the Cohansey. The first of two wells has been completed, yielding 1.4 MGD of brackish groundwater. Similar performance from the second well will exceed the design goal. When the initial system comes on line during the summer of 1998, New Jersey will have its first public water supply derived from desalinated groundwater. The use of desalinated groundwater balances competing demands for water resources in the southern Cape Region of New Jersey, allowing continued economic growth while reducing human impacts on a threatened aquifer.
POLYNOMIAL‐BASED DISAGGREGATION OF HOURLY RAINFALL FOR CONTINUOUS HYDROLOGIC SIMULATION1
Authors: Durrans S. Rocky , Burian Steven J. , Nix Stephan J. , Hajji Ahmed , Pitt Robert E. , Fan Chi‐Yuan , Field Richard 
Published: June 2007

ABSTRACTHydrologic modeling of urban watersheds for designs and analyses of stormwater conveyance facilities can be performed in either an event‐based or continuous fashion. Continuou simulation requires, among other things, the use of a time series of rainfall amounts. However, for urban drainage basins, which are typically small, the temporal resolution of the rainfall time series must be quite fine, and often on the order of 5 to 15 minutes. This poses a significant challenge because rainfall‐gauging records are usually kept only for hourly or longer time steps. The time step sizes in stochastic rainfall generators are usually also too large for application to urban runoff modeling situations. Thus, there is a need for methods by which hourly rainfall amounts can be disaggregated to shorter time intervals. This paper presents and compares a number of approaches to this problem, which are based on the use of polynomial approximating functions. Results of these evaluations indicate that a desegregation method presented by Ormsbee (1989) is a relatively good performer when storm durations are short (2 hours), and that a quadratic spline‐based approach is a good choice for longer‐duration storms. Based on these results, the Ormsbee technique is recommended because it provides good performance, and can be applied easily to long time series of precipitation records. The quadratic spline‐based approach is recommended as a close second choice because it performed the best most consistently, but remains more difficult to apply than the Ormsbee technique. Results of this study also indicate that, on average, all of the disaggregation methods evaluated introduce a severe negative bias into maximum rainfall intensities. This is cause for some well‐justified concern, as the characteristics of runoff hydrographs are quite sensitive to maximum storm intensities. Thus, there is a need to continue the search for simple yet effective hourly rainfall disaggregation methods.
DEFINING WATERSHED‐SCALE EVAPORATION USING A NORMALIZED DIFFERENCE VEGETATION INDEX1
Authors: Szilagyi Jozsef , Parlange Marc B. 
Published: June 2007

ABSTRACTMonthly composites of the Normalized Difference Vegetation Indices (NDVI), derived from the National Oceanic and Atmospheric Administration's (NOAA) Advanced Very High Resolution Radiometer (AVILRR), were transformed linearly into monthly evaporation rates and compared with detailed hydrologic‐model simulation results for five watersheds across the United States. Model‐simulated monthly evaporation values showed high correlations (mean R2= .77) with NDVI‐derived evaporation estimates. These latter estimates, used in a classical water balance model, resulted in equally accurate simulations of monthly runoff than when the model was run to estimate monthly evaporation via soil moisture accounting. Comparison of NDVI‐derived evaporation estimates with pan data showed promise for transforming NDVI values into evaporation estimates under both wet and water‐limiting conditions without resorting to the application of any kind of calibrated hydrologic models.
COMPARISON OF DESIGN STORM CONCEPTS USING CONTINUOUS SIMULATION WITH SHORT DURATION STORMS1
Authors: Nnadi F. N. , Kline F. X. , Wray H. L. , Wanielista M. P. 
Published: June 2007

ABSTRACT: The objectives of this paper were to test the ability of various design storm distributions to simulate the actual rainfall pattern and to compare the runoff rates used in the design of stormwater management devices in the State of Florida using continuous simulation approach. The analyses were performed for four gaged stations to evaluate the applicability of design storm distributions in different parts of the State of Florida.The approach used in this study compared the peak runoff rates from design storms based on the various distributions to those that would result from actual rainfall events. A series of continuous runoff rates were developed through the use of actual fifteen‐minute recorded rainfall data, Horton type infiltration decay and recovery rate, and a continuous simulation model. The runoff rates were analyzed using frequency distributions to obtain peak runoff rates associated with different return periods based on the assumption that the continuous simulation approach closely predicts the actual runoff rates from the gaged stations. The results show that the behavior of the design storm distributions varies for different watershed characteristics in different parts of the state. The study also suggests that in general the Florida Department of Transportation and the Suwanne River Water Management (FDOT/ SRWMD) distributions appeared to agree with the continuous simulation results.
ON‐FARM WATER CONSERVATION PRACTICES IN SOUTHERN ALBERTA1
Authors: Johnston Thomas R. R. , Kromm David E. , Byrne James M. 
Published: June 2007

ABSTRACT: In southern Alberta, as elsewhere, pressures on limited water supplies are increasing. Not surprisingly, a great deal of attention has been focused on irrigated agriculture, which accounts for the largest share of water consumed in the region. In order to meet broadly accepted water conservation goals, some commentators have suggested that irrigation water use should be metered and that irrigators should be charged based on the amount of water used. An alternative proposal would have water management authorities rely upon the perceived adaptability of irrigators. This paper offers a perspective on the willingness of irrigators to conserve water.Based on a survey of 183 irrigation farmers conducted over the summer and early fall of 1998, we found that irrigators are generally aware of the need to conserve water and soil moisture, and that a variety of water conserving strategies were being employed. Water saving technologies specific to irrigation agriculture were less widely adopted. The findings suggest that there is considerable potential to reduce the amount of water consumed by the irrigation sector through increased efficiency, but that change will be limited if current economic circumstances and institutional arrangements persist.