bluuebunny/crossref_metadata_2025 huggingface dataset:
IMPROVING REGIONAL‐MODEL ESTIMATES OF URBAN‐RUNOFF QUALITY USING LOCAL DATA1
Authors: Hoos Anne B.
Published: June 2007

ABSTRACT: Urban water‐quality managers need load estimates of storm‐runoff pollutants to design effective remedial programs. Estimates are commonly made using published models calibrated to large regions of the country. This paper presents statistical methods, termed model‐adjustment procedures (MAPs), which use a combination of local data and published regional models to improve estimates of urban‐runoff quality. Each MAP is a form of regression analysis that uses a local data base as a calibration data set to adjust the regional model, in effect increasing the size of the local data base without additional, expensive data collection. The adjusted regional model can then be used to estimate storm‐runoff quality at unmonitored sites and storms in the locality. The four MAPs presented in this study are (1) single‐factor regression against the regional model prediction, Pu; (2) least‐squares regression against Pu; (3) least‐squares regression against Pu and additional local variables; and (4) weighted combination of Pu and a local‐regression prediction. Identification of the statistically most valid method among these four depends upon characteristics of the local data base. A MAP‐selection scheme based on statistical analysis of the calibration data set is presented and tested.
NON‐ZERO LOWER LIMIT IN LOW FLOW FREQUENCY ANALYSIS?1
Authors: Lawal Semiu A. , Watt W. Edgar.
Published: June 2007

ABSTRACT: The implications of fitting distributions with non‐zero lower limits to low flow data are examined. The 3‐parameter Weibull distribution is fitted to annual minimum flow series from 60 long term stations in Canada. The relations between the estimated lower limit and three sampling variables (skewness, smallest, and largest observations) were investigated. The lower limit strongly depends on the sample skewness; it varies directly with the sample skewness, which in turn is highly influenced by the largest observation. For a given skewness, the value of the estimated lower limit is determined by the value of the smallest observation. Therefore, the lower limit cannot be accurately determined, and the resulting low flow estimates will be either too small or too high.
QUALITY OF 1995 SPRING TOTAL DISSOLVED GAS DATA: COLUMBIA AND SNAKE RWERS1
Authors: Bisbal Gustavo A. , Ruff James D.
Published: June 2007

ABSTRACT: The quality of the U.S. Army Corps of Engineers' (Corps) total dissolved gas (TDG) data base for the 1995 spring spill season was reviewed to determine the value of this information in real‐time management decisions regarding river operations. We concluded that problems in transmitting, archiving, correcting and interpreting the records constitute significant sources of data anomalies that affect the accuracy and reliability of information necessary to manage spill and TDG in the Columbia and Snake rivers. The data base that was reviewed covers 25 selected Columbia and Snake river stations, and includes real‐time TDG data needed to regulate spill operations to maintain gas levels within state water quality standards and to monitor effects on fish and aquatic life during the salmon migration season. A wide range of anomalies (daily averages missing or in error or based on incomplete records) was detected in more than one‐third (37 percent) of the Corps' gas data base. Extreme anomalies (daily averages including errors and discontinuities for more than eight hours in a day) were found in 16 percent of the data base. The Fish Passage Center, also reviewed the Corps' data and reported an overall 33 percent incidence of anomalous days. Despite arriving at similar findings about the Corps' data base, we detected a 28 percent discrepancy in the type of data anomalies between our analyses. Real. time improvements in the quality of the dissolved gas data base are necessary to provide managers with a reliable product from this monitoring effort.
CHANNEL NETWORK EXTENSION BY LOGGING ROADS IN TWO BASINS, WESTERN CASCADES, OREGON1
Authors: Wemple Beverley C. , Jones Julia A. , Grant Gordon E.
Published: June 2007

ABSTRACT:Based on field surveys and analysis of road networks using a geographic information system (GIS), we assessed the hydrologic integration of an extensive logging‐road network with the stream network in two adjacent 62 and 119 km2basins in the western Cascades of Oregon. Detailed surveys of road drainage for 20 percent of the 350 km road network revealed two hydrologic flow paths that link roads to stream channels: roadside ditches draining to streams (35 percent of the 436 culverts examined), and roadside ditches draining to culverts with gullies incised below their outlets (23 percent of culverts). Gully incision is significantly more likely below culverts on steep (< 40 percent) slopes with longer than average contributing ditch length. Fifty‐seven percent of the surveyed road length is connected to the stream network by these surface flowpaths, increasing drainage density by 21 to 50 percent, depending on which road segments are assumed to be connected to streams. We propose a conceptual model to describe the hydrologic function of roads based on two effects: (1) a volumetric effect, increasing the volume of water available for quickflow and (2) a timing effect, altering flow‐routing efficiency through extensions to the drainage network. This study examines the second of these two effects. Future work must quantify discharge along road segments connected to the stream network in order to more fully explain road impacts on basin hydrology.
DECISION SUPPORT SYSTEM FOR RESERVOIR OPERATION1
Authors: Huang Wen‐Cheng
Published: June 2007

ABSTRACT: A decision support system to determine reservoir releases in an uncertain environment during the dry season was developed. A key characteristic of the decision support system is its recursive procedure that processes observations to obtain the most feasible estimate. The system consists of three components: (1) a hydrologic model; (2) an optimization model, and (3) a fuzzy decision model. This methodology was applied to the operation of the Techi reservoir in central Taiwan. Three criteria (public water supply, irrigation, and hydropower) were taken into account within the operation process. Simulation results show that the decision support system can successfully assist government officials in determining operating policy for the Techi reservoir during the dry season. Also, the system is simple enough to lead to a rapid transfer of theoretical knowledge into practice.
ECONOMIC IMPACTS OF GUIDED WHITEWATER RAFTING: A STUDY OF FIVE RIVERS1
Authors: English Donald B. K. , Bowker J. M.
Published: June 2007

ABSTRACT: This paper presents estimates of the statewide economic impacts of guided whitewater rafting on five rivers in six states: the Nantahala (North Carolina), Gauley (West Virginia), Kennebec (Maine), Middle Fork of the Salmon (Idaho), and Chattooga (Georgia‐South Carolina). Except for the Chattooga and Middle Fork, rafting is dependent on upstream dam releases. Guide fees range from about $15 per trip on the Nantahala to over $1,000 on the Middle Fork. Economic impacts per nonresident 1000 visitors increase along with length of the rafting trip and remoteness of the river. Total industrial output per 1000 nonresident visitors ranged from $95,000 on the Nantahala to over $2.5 million on the Middle Fork. However, because of differences in annual visitation levels, total impacts were greatest at the Nantahala, at over $14 million in 1993. Multipliers for all economic measures were relatively consistent over the rivers. Employment multipliers (Type III) ranged from 1.67 to 1.90, income multipliers from 2.0 to 2.4, and industrial output multipliers from 2.1 to 2.5.
GOAL‐ORIENTED AGRICULTURAL WATER QUALITY LEGISLATION1
Authors: Gannon R. W. , Osmond D. L. , Humenik F. J. , Gale J. A. , Spooner J.
Published: June 2007

ABSTRACT: While significant nonpoint source (NIPS) pollution control progress has been made since passage of Section 319 in the 1987 Water Quality Act, existing federal legislation does not provide for the most timely and cost‐effective NIPS pollution reduction. In this paper, we use findings from the Rural Clean Water Program and other nationwide agricultural NIPS pollution control programs, building on legislative history to recommend a coordinated and efficient direction for agricultural water quality legislation. A collaborative framework should be established to accomplish the goals of the Clean Water Act (CWA), Coastal Zone Management Act (CZMA), and the Conservation Title of the Farm Bill. Valuable elements of the 1990 CZMA amendments that created a coastal NIPS program should be subsumed into the CWA. The CWA should reemphasize use of receiving water quality criteria and standards and should allow states flexibility to tailor basin‐scale NPS program implementation to local needs. Implementation should involve targeting of NIPS pollution control efforts to critical land treatment areas and use of systems of best management practices to address these targeted water quality problems. The 1995 Farm Bill should reorient production incentives toward water quality to support the collaborative framework, implementing ecologically sound source reduction principles. The Farm Bill and the CWA should contain interrelated provisions for voluntary, incentive‐assisted producer participation and fallback regulatory measures. Such coordinated national water quality and Farm Bill legislation that recognizes the need for flexibility in state implementation is supported as the most rational and cost‐effective means of attaining water quality goals.
CONTROL OF NATURAL BRINE SPRINGS IN BRAZOS RWER BASIN PART I: RECOVERY SYSTEM1
Authors: James Wesley P. , Chakka Kesava B. , Mascianglioli Panfilo A.
Published: June 2007

ABSTRACT: The water quality in the Brazos River in Texas is seriously degraded by natural salt pollution in the upper Brazos River. Controlling the natural salt springs and seeps in the Dove Creek area will reduce the chloride concentration in the Brazos River by nearly 45 percent. The brine that is discharged as natural springs and seeps in the Dove Creek area is from two sources: (1) local recharge and (2) deep‐basin. A preliminary design of the brine recovery system was developed in this phase of the study. A three‐dimensional, finite element model to simulate groundwater flow in anisotropic and heterogeneous media under steady state conditions was developed to assist with the design and evaluation of brine recovery systems in the Dove Creek area. Model simulations indicate that a shallow‐well brine recovery system pumping about 56 l/s (2 cfs) of brine will eliminate approximately 45 percent of chloride discharging into the upper Brazos River.
SWMHMS ‐ SMALL WATERSHED MONTHLY HYDROLOGIC MODELING SYSTEM1
Authors: Allred B. , Haan C. T.
Published: June 2007

ABSTRACT: SWMHMS is a conceptual computer modeling program developed to simulate monthly runoff from a small nonurban watershed. The input needed to run model simulations include daily precipitation, monthly data for evapotranspiration determination (average temperature, crop consumptive coefficients, and percent daylight hours), and six watershed parameter values. Evapotranspiration was calculated with the Blaney‐Criddle equation while surface runoff was determined using the Soil Conservation Service curve number procedure. For watershed parameter evaluation, SWMHMS provides options for both optimization and sensitivity analysis. Observed runoff data are required along with the model input previously mentioned in order to conduct parameter optimization. SWMEIMS was tested with data from six watersheds located in different regions of the United States. Model accuracy was generally found to be very good except on watersheds having substantial snowfall accumulation.

In having only six watershed parameters, SWMHMS is less complex to use than many other computer programs that calculate monthly runoff. Consequently, SWMHMS may find its greatest application as an educational tool for students learning principles of hydrologic modeling, such as parameter evaluation procedures and the impacts of input data uncertainty on model results.
THE EFFECTS OF ARTIFICIAL CIRCULATION ON A SMALL NORTHEASTERN IMPOUNDMENT1
Authors: Barbiero Richard P. , Ashby Steven L. , Kennedy Robert H.
Published: June 2007

ABSTRACT: Artificial circulation was applied at East Sidney Lake, a small, eutrophic impoundment in New York, to improve the water quality of the reservoir and tailwater. Treatment was successful at both reducing the stability of the reservoir and maintaining higher mean oxygen concentrations in the bottom waters. Discharge waters had lower metals and phosphorus concentrations during treatment years. However, vertical temperature differences, although minimal, were still sufficient to permit chemical stratification and some phosphorus release from the sediments. Frequent mixing events during periods of low stability, and runoff from storm events, also appeared to increase transport of phosphorus into the epilimnion. Overall, treatment did not result in decreases in algal populations or improvements in water clarity.
PRIVATIZING GOVERNMENT IRRIGATION PROJECTS IN NEW ZEALAND1
Authors: Farley Peter J. , Simon Benjamin M.
Published: June 2007

ABSTRACT: This paper discusses the sale of the Government. owned irrigation projects in New Zealand, including the development of irrigation projects in New Zealand, the rationale behind the transfer of ownership to existing irrigators, the sale process, and the outcomes. The transfer of ownership to private entities was undertaken primarily to remove the Government from irrigation activities. However, the sales were also thought to have the poten. tial to improve the efficiency of the projects' operation. The sale process was a negotiated process so that maximizing revenues was not the primary objective of the government. In many cases the government paid irrigators to assume ownership of the schemes. Preliminary data suggest that schemes are being more efficiently operated under private ownership. However, additional data need to be collected on a systematic basis to determine the magnitude of any efficiency gains.
222RN IN THE WATER DISTRIBUTION SYSTEM OF TUCSON, ARIZONA1
Authors: Kalin Robert M. , Smith Bruce D. , Long Austin
Published: June 2007

ABSTRACT: A study of 222Rn concentrations in the water distribution system of Tucson, Arizona, revealed levels of 60 to 1260 pCi/L in domestic waters. These measurements are comparable to levels of between 80 and 1400 pCi/l for 222Rn found in ground water samples in the North‐Central Tucson basin (Kalin et al., 1995). Estimated loss of 222Rn due to radioactive decay during travel from the well head to the home ranges from 8 to 50 percent.
A WATERSHED‐LEVEL ECOLOGICAL RISK ASSESSMENT METHODOLOGY1
Authors: Hession W. Cully , Storm Daniel E. , Haan C. Thomas , Burks Sterling L. , Matlock Marty D.
Published: June 2007

ABSTRACT: We present an ecological risk assessment methodology at the watershed level for freshwater ecosystems. The major component is a pollutant transport and fate model (a modified EUTROMOD) with an integrated uncertainty analysis utilizing a two‐phase Monte Carlo procedure. The uncertainty analysis methodology distinguishes between knowledge uncertainty and stochastic variability. The model assesses the ecological risk of lentic (lake) ecosystems in response to the stress of excess phosphorus resulting in eutrophication. The methodology and model were tested on the Wister Lake watershed in Oklahoma with the lake and its trophic state as the endpoint for ecological risk assessment. A geographic information system was used to store, manage, and manipulate spatially referenced data for model input.
NPS MODEL PARAMETER UNCERTAINTY ANALYSIS FOR AN OFF‐STREAM RESERVOIR1
Authors: Kao Jehng‐Jung , Hong Hong‐Jyh
Published: June 2007

ABSTRACT: Parameter uncertainties exert a significant effect on nonpoint source pollution (NPS) modeling results. A decision made on the basis of such results may thereby be inappropriate. In this work, the parameter uncertainty is analyzed to explore an improved modeling procedure. Drainage patterns generated from digital elevation data and rainfall are the major parameters examined. A case study for the watershed of the Posan off‐stream reservoir is implemented. A significant spatial variation of NPS distribution simulated with a drainage pattern generated from varied methods is observed. The effects of rainfall randomness on the spatial loading distribution are assessed and computed based on a Monte Carlo simulation. The proposed procedure is capable of improving the quality of modeling results and the decision for an appropriate control strategy.
SIMULATING THREE‐DIMENSIONAL GROUND WATER RESPONSE IN A SMALL MOUNTAINOUS WATERSHED1
Authors: Flerchinger G. N. , Shang Shuangling , Finnie J. I.
Published: June 2007

ABSTRACT: Snowmelt from deep mountainous snowpacks is seldom rapid enough to exceed infiltration rates; thus, the source of streamflow in many mountainous watersheds is snowmelt recharge through shallow ground water systems. The hydrologic response and interaction between surface and sub‐surface flow processes in these watersheds, which is controlled by basin structure, the spatial distribution of snowmelt, and the hydrogeology of the subsurface, are not well understood. The purpose of this study was to test a three‐dimensional ground water model using simulated snowmelt input to simulate ground water response to spatially distributed snowmelt on the Upper Sheep Creek Watershed located within the Reynolds Creek Experimental Watershed in Southwestern Idaho. The model was used to characterize the mountainous aquifer and to delineate the subsurface flow mechanisms. Difficulty in finding a reasonable combination of grid spacing and time stepping within the model was encountered due to convergence problems with the Picard solution to the non‐linear variably saturated ground water flow equations. Simulation results indicated that flow may be either unconfined or confined depending on inflow rate and hydrogeologic conditions in the watershed. The flow mechanism had a much faster response time when confined flow occurred. Response to snowmelt from a snow drift approximately 90 m away took only a few hours when flow was confined. Simulated results showed good agreement with piezometer measurements both in magnitude and timing; however, convergence problems with the Picard solution limited applicability of the model.
PROFESSIONAL WATER RESOURCES EDUCATION FOR THE FUTURE… ARE WE READY?1
Authors: Spangenberg N. Earl.
Published: June 2007

ABSTRACT: Water resources professionals are being increasingly called upon to address complex problems which require the interaction of several individuals operating as a planning or implementation team. Education for water resources professionals must move to meet the demands of this mode of operation. To best prepare the student, educational programs must focus not only on technical competence but must also incorporate concepts of cooperative problem solving with individuals from a diversity of backgrounds as a part of the curriculum. Among strategies which may work are academic requirements outside of the technical specialty, modification of existing course materials, and inclusion of outside faculty as a part of departmental curriculum preparation.
HYDRAULIC AND ECONOMIC BENEFITS OF DOWNSPOUT DWERSION1
Authors: Kaufman Martin M. , Wurtz Matthew
Published: June 2007

ABSTRACT: A downspout diversion program in an urban area is evaluated to assess the impacts on sanitary sewer flow volumes and cost effectiveness. Sanitary sewer flows and wastewater treatment cost data are compared for the five years before and 1.25 years after the downspout diversion was completed. In order to establish a cause and effect relationship between flow volumes and downspout diversion, measurements of precipitation, consumption patterns, and system loss (maintenance, fire flows, main ruptures) for the before and after time periods were obtained. The results indicate the downspout diversion contributed to a reduction of over 25 percent in the mean flow volumes within the sanitary sewer collection network during all rainfall events, with flow reductions ranging from 25 percent to 62 percent for rainfall depths between 6 mm (0.25 inches) and 25.4 mm (1.0 inches). Costs incurred for wastewater treatment were also reduced significantly, as overtime for overflow maintenance was eliminated. Downspout diversion is a viable nonstructural alternative for sthrmwater flow reduction in highly urbanized communities which may lack available space for large scale detention facilities.
NITROGEN AND PHOSPHORUS IN SURFACE WATERS OF THE UPPER COLORADO RWER BASIN1
Authors: Spahr N. E. , Wynn K H.
Published: June 2007

ABSTRACT: As part of a basinwide water‐quality study, nitrogen and phosphorus data for the Upper Colorado River Basin from the Colorado‐Utah State line to the Continental Divide were analyzed for spatial distributions, concentrations associated with various land uses, and temporal trends. Nitrogen and phosphorus concentrations generally increased in a downstream direction. Some nutrient concentrations were elevated at some sites in the upper parts of the basin in areas influenced by increasing urbanization. Sites were grouped according to land use and site type, and median nutrient concentrations were compared among groups. Sites within the agricultural areas of the basin generally had the highest concentrations of nitrogen and phosphorus; concentrations for main‐stem, tributary, and urbanization sites were slightly lower than for the agricultural sites. Background sites, or sites with minimal land‐use impacts, had very low median nutrient concentrations. Several sites with long‐term data were analyzed for temporal trends in concentrations. Several statistically significant downward trends of low and moderate magnitude were observed for nitrogen and phosphorus species. No upward trends were observed in the data at any site.
ENSO: EXTREME CLIMATE EVENTS AND THEIR IMPACTS ON ASIAN DELTAS1
Authors: Chang William Y B.
Published: June 2007

ABSTRACT: Proxy climate data for the last 500 years collected from the archives of counties in the Yangtze River Delta, China, were analyzed to identify the occurrence of extreme climate events, the pattern of such occurrences and their relationships to El Nino‐Southern Oscillation (ENSO). This study identified the cycle periods of 3.5, 5.5 and 8.6 years for floods and 18.5 years for droughts in the Yangtze River Delta during the last 500 year period and noted 16 regional (delta wide) extreme events during this period. All regional (delta wide) extreme climate events during the last 500 years (since 1500 A.D.) occurred either during or immediately after ENSO (5–6 year) activities. Hydrological impacts of extreme climate events, such as major floods and droughts, on human systems have long been among the foremost concerns of the Pacific Rim countries. Management of systems increasingly dominated by humans, such as Asian delta regions, should, therefore, include consideration of major climate variability, ENSO events and the extent of climate changes, as well as consideration of the trends associated with human growth and institutional changes.
PREDICTION OF TWO‐YEAR PEAK STREAM‐DISCHARGES USING NEURAL NETWORKS1
Authors: Muttiah Ranjan S. , Srinivasan Raghavan , Allen Peter M.
Published: June 2007

ABSTRACT: The cascade correlation neural network was used to predict the two‐year peak discharge (Q2) for major regional river basins of the continental United States (US). Watersheds ranged in size by four orders of magnitude. Results of the neural network predictions ranged from correlations of 0.73 for 104 test data in the Souris‐Red Rainy river basin to 0.95 for 141 test data in California. These results are improvements over previous multilinear regressions involving more variables that showed correlations ranging from 0.26 to 0.94. Results are presented for neural networks trained and tested on drainage area, average annual precipitation, and mean basin elevation. A neural network trained on regional scale data in the Texas Gulf was comparable to previous estimates of Q2 by regression. Our research shows Q2 was difficult to predict for the Souris‐Red Rainy, Missouri, and Rio Grande river basins compared to the rest of the US, and acceptable predictions could be made using only mean basin elevation and drainage areas of watersheds.
USE OF FIRST‐ORDER UNCERTAINTY ANALYSIS TO OPTIMIZE SUCCESSFUL STREAM WATER QUALITY SIMULATION1
Authors: Warwick John J.
Published: June 2007

ABSTRACT: A first‐order uncertainty technique is developed to quantify the relationship between field data collection and a modeling exercise involving both calibration and subsequent verification. A simple statistic (LTOTAL) is used to quantify the total likelihood (probability) of successfully calibrating and verifying the model. Results from the first‐order technique are compared with those from a traditional Monte Carlo simulation approach using a simple Streeter‐Phelps dissolved oxygen model. The largest single difference is caused by the filtering or removal of unrealistic outcomes within the Monte Carlo framework. The amount of bias inherent in the first‐order approach is also a function of the magnitude of input variability and sampling location. The minimum bias of the first‐order technique is approximately 20 percent for a case involving relatively large uncertainties. However the bias is well behaved (consistent) so as to allow for correct decision making regarding the relative efficacy of various sampling strategies. The utility of the first‐order technique is demonstrated by linking data collection costs with modeling performance. For a simple and inexpensive project, a wise and informed selection resulted in an LTOTAL value of 86 percent, while an uninformed selection could result in an LTOTAL value of only 55 percent.
IMPROVEMENT OF LEACHATE PREDICTION THROUGH MUNICIPAL SOLID WASTE LAYERS1
Authors: Uguccioni Mark , Zeiss Chris
Published: June 2007

ABSTRACT: Existing leachate prediction models over‐ or underestimate leachate generation by up to three orders of magnitude. Practical experiments show that channeled flow in waste leads to rapid discharge of large leachate volumes and heterogeneous moisture distributions. In order to more accurately predict leachate generation, leachate models must be improved. To predict moisture movement through waste, the one‐domain water balance model HELP, and two‐domain PREFLO, are tested. Experimental waste and leachate flow values are compared with model predictions. When calibrated with experimental parameters, the HELP model yields reasonable predictions of cumulative leachate flow and PREFLO provides estimates of breakthrough time. In the short term, field capacity has to be reduced to 0.12 and effective storage and hydraulic conductivity of the waste must be increased to 0.2 and 2.2 cm/s respectively. In the long term, a new modeling approach must be developed to adequately describe the moisture movement mechanisms.
SPATIAL DELINEATION OF BIOTIC AND ABIOTIC GRADIENTS IN A RURAL NEW YORK RESERVOIR1
Authors: Melcher Jill , Soracco Reginald J. , Boylen Charles W.
Published: June 2007

ABSTRACT: The spatial changes in abiotic and biotic variables from riverine to lacustrine areas characterized by the river‐lake concept of reservoir function was applied to the Tomhannock Reservoir, Rensselaer County, New York. To identify these longitudinal gradients, a two‐year investigation (May 1991 to October 1992) was conducted to measure primary productivity, nutrient concentrations, chlorophyll α and phytoplankton biomass at three locations in the 705‐ha water supply reservoir. Emphasis was placed on the measurement of primary production using the carbon‐14 artificial incubator (photosynthetron) technique. The average annual production in 1992 was 247.3 gm−2 245 d−1, ranging from 52 to 2677 mg C m−2. Mean alphaB (assimilation efficiency), PBm (assimilation number), and Ik (saturation irradiance) were 4.40 mg C mgChl−1 E−1 m−2, 3.82 mg C mgChl−1 h−1, and 236.5 μE m−2 s−1, respectively. Neither seasonal nor spatial variability of these photosynethetic parameters were observed. Except for Secchi depth, distinct longitudinal zones from river inflow to darn were not statistically demonstrated in the Tomhannock Reservoir. Mean extinction coefficient, chlorophyll α and total phosphorus concentrations decreased; Secchi transparency and phytoplankton biomass increased; while primary productivity and dissolved inorganic nitrogen concentration remained the same from headwater to darn. These baseline data will be used to assess the future effectiveness of best management practices (BMPs) recently instituted on selected watershed farmland in an attempt to reduce the detrimental impact of agricultural activities on drinking water quality.
FLUME CONDITION ASSESSMENT IN COLORADO1
Authors: Abt Steven R. , Ruth Bryan C.
Published: June 2007

ABSTRACT: A study was conducted in which 66 Parshall flumes used for agricultural flow measurement were assessed for physical integrity, settlement, and submergence. A total of 292 physical defects was documented. A flow measurement error analysis was performed indicating that 52 percent of the flumes measured flow beyond ±3 percent of the correct value and 41 percent of the flumes measured flow beyond ±5 percent. The findings indicate that the infrastructure is aging. The flow measurement system comprised of flumes no longer provide an accurate accounting of water through the distribution network.
EVALUATION OF NINE MODELS FOR UNGAUGED URBAN BASINS IN LOUISIANA1
Authors: Yu Fang Xin , Pardue John , Adrian Donald D.
Published: June 2007

ABSTRACT: Nine flood‐estimation models used for ungauged urban watersheds in Louisiana were evaluated. Flood‐quantile predictions from simple regression models calibrated by local data were found to be more reliable than those more complicated models or models with many parameters that may not be accurately estimated. Flood prediction from models developed by using regionalization techniques were found to be reasonably good. Finally, application of a model outside of its limitations or domain may lead to substantial prediction error.
WETLAND DESIGN METHODS FOR RESIDENTIAL WASTEWATER TREATMENT1
Authors: Sauter Gregory , Leonard Kathleen
Published: June 2007

ABSTRACT: Constructed wetlands have recently gained popularity as an alternative method for wastewater treatment. This paper compares two design methodologies currently used for constructed wetlands; Tennessee Valley Authority (TVA) and the Environmental Protection Agency (EPA) methods. A discussion of parameters for both methods is given and a wetland treatment system is designed for an individual residence with typical BOD5 loads and flow rates.

Calculation results revealed significant discrepancies in the required constructed wetlands volume, and thus detention time, stemming from inherent differences in the design methodologies. The EPA method relies heavily on plug flow kinetics, and is therefore sensitive to changes in the reaction rate constant and media porosity. Conversely, TVA determines the surface area by sizing in accordance with a recommended hydraulic loading criterion and is affected only by the hydraulic flow rates. This study concluded that a constructed wetland is a viable option under design considerations that are not favorable for traditional on‐site wastewater treatment methods. However, it is recommended that conservative values for flow and loading rates be assumed to assure complete treatment for either of the design methods.
IMPLICATIONS OF C.A.R.E. VS. SOUTHVIEW FARM ON THE U.S. LIVESTOCK AND POULTRY INDUSTRY1
Authors: Martin John H.
Published: June 2007

ABSTRACT: On May 19, 1993, a jury in the U.S. District Court for the Western District of New York found Southview Farm and Richard H. Popp guilty of violating the Clean Water Act on five occasions. The violations were the result of storm water runoff from a site used for disposal of dairy cattle manure from an unpermitted concentrated animal feeding operation. The presiding District Court judge later dismissed the jury verdict, and subsequently a U.S. Court of Appeals for the Second Circuit reversed the dismissal. The Court of Appeals concluded that the discharges were not exempt as agricultural storm water discharges, and that the manure spreaders involved were point sources. Because the use of animal manures in crop production activities will result, unavoidably, in the discharge of some pollutants to adjacent surface waters, a rational and universally applicable basis is needed to determine when such discharges are point versus nonpoint source. Current statutes and regulations do not delineate clearly such a boundary. To address this lack of specificity, I propose that application rates be based on recommended crop nutrient needs.
LONG‐TERM WATERSHED RESEARCH AND MONITORING TO UNDERSTAND ECOSYSTEM CHANGE IN PARKS AND EQUIVALENT RESERVES1
Authors: Herrmann Raymond
Published: June 2007

ABSTRACT: Integrated watershed ecosystem studies in National Parks or equivalent reserves suggest that effects of external processes on “protected” resources are subtle, chronic, and long‐term. Ten years of data from National Park watersheds suggests that temperature and precipitation changes are linked to nitrogen levels in lakes and streams. We envision measurable biotic effects in these remote watersheds, if expected climate trends continue. The condition of natural resources within areas set aside for preservation are difficult to ascertain, but gaining this knowledge is the key to understanding ecosystem change and of processes operating among biotic and abiotic ecosystem components. There is increasing evidence that understanding the magnitude of variation within and between such processes can provide an early indication of environmental change and trends attributable to human‐induced stress. The following four papers are case studies of how this concept has been implemented.* These long‐term studies have expanded our knowledge of ecosystem response to natural and human‐induced stress. The existence of these sites with a commitment to gathering “long‐term” ecosystem‐level data permits research activities aimed at testing more important hypotheses on ecosystem processes and structure.
WATERSHED RESPONSES TO CLIMATE CHANGE AT GLACIER NATIONAL PARK1
Authors: Fagre Daniel B. , Comanor Peter L. , White Joseph D. , Hauer F Richard , Running Steven W.
Published: June 2007

ABSTRACT: We have developed an approach which examines ecosystem function and the potential effects of climatic shifts. The Lake McDonald watershed of Glacier National Park was the focus for two linked research activities: acquisition of baseline data on hydrologic, chemical and aquatic organism attributes that characterize this pristine northern rocky mountain watershed, and further developing the Regional Hydro‐Ecosystem Simulation System (RHESSys), a collection of integrated models which collectively provide spatially explicit, mechanistically‐derived outputs of ecosystem processes, including hydrologic outflow, soil moisture, and snow‐pack water equivalence. In this unique setting field validation of RHESSys, outputs demonstrated that reasonable estimates of SWE and streamflow are being produced. RHESSys was used to predict annual stream discharge and temperature. The predictions, in conjunction with the field data, indicated that aquatic resources of the park may be significantly affected. Utilizing RHESSys to predict potential climate scenarios and response of other key ecosystem components can provide scientific insights as well as proactive guidelines for national park management.
AN ILLUSTRATION OF MODEL STRUCTURE IDENTIFICATION1
Authors: Qian Song S.
Published: June 2007

ABSTRACT: The purpose of this article is to discuss the importance of uncertainty analysis in water quality modeling, with an emphasis on the identification of the correct model specification. A wetland phosphorus retention model is used as an example to illustrate the procedure of using a filtering technique for model structure identification. Model structure identification is typically done through model parameter estimation. However, due to many sources of error in both model parameterization and observed variables and data, error‐in‐variable is often a problem. Therefore, it is not appropriate to use the least squares method for parameter estimation. Two alternative methods for parameter estimation are presented. The first method is the maximum likelihood estimator, which assumes independence of the observed response variable values. In anticipating the possible violation of the independence assumption, a second method, which coupled a maximum likelihood estimator and Kalman filter model, was presented. Furthermore, a Monte Carlo simulation algorithm is presented as a preliminary method for judging whether the model structure is appropriate or not.
INDUSTRY COMPLIANCE WITH STORM WATER POLLUTION PREVENTION REGULATIONS: THE CASE OF TRANSPORTATION INDUSTRY FACILITIES IN CALIFORNIA AND THE LOS ANGELES REGION1
Authors: Duke L. Donald , Beswick Paul G.
Published: June 2007

ABSTRACT: Pollutants in urban storm water runoff, a significant and increasing fraction of pollutants in some waters of the U.S., originate from multiple activities. The industrial sector, one source category, is subject to federal and state‐level storm water pollution prevention regulations, primarily General NPDES Permits that rely heavily on facility operators to identify themselves and develop appropriate site‐specific pollutant controls. Degree of compliance is not readily determined and enforcement is inhibited because no publicly‐available inventories contain data necessary to comprehensively identify facilities required to comply. This research evaluates the first stage of compliance, facility self‐identification, concentrating on the motor‐vehicle, transportation industry category using data at three scales: statewide, regional, and local or watershed. Data for California statewide and for the Los Angeles region show about 8 percent to 15 percent of motor‐vehicle transportation facilities have complied with first‐stage requirements. However, facility‐specific evaluation in one Los Angeles County watershed suggests less than 50 percent of facilities in the industry conduct industrial activities of the kind covered by regulations; others need not comply. Results show strong variation by industry category. Second‐stage compliance, follow‐up reporting, is also evaluated for the Los Angeles region. About 17 percent to 34 percent of facilities completing first‐stage requirements have also completed second‐stage requirements.
RESPONDING TO DROUGHT: COMMON THREADS FROM THE PAST, VISIONS FOR THE FUTURE1
Authors: Wilhite Donald A.
Published: June 2007

ABSTRACT: A number of studies conducted since the late 1970s have evaluated state and federal responses to drought in the United States. Each of these studies identified a number of key issues and impediments that needed to be addressed to improve the nation's ability to cope with and prepare for future episodes of drought. A content analysis of these studies was performed to identify common threads in their recommendations. The premise of this analysis was that the series of drought years that occurred between 1986 and 1992 and recurred between 1994 and 1996 increased awareness of our nation's continuing and apparent growing vulnerability to drought. This awareness has led to greater consensus among principal constituents and stakeholders, and also a greater sense of urgency to implement actions now to lessen vulnerability. The results of this analysis revealed that several themes recur: create an integrated national drought policy and plan; develop an integrated national climate monitoring (drought watch) system; incorporate drought in FEMA's National Mitigation Strategy; conduct post‐drought audits of response efforts; establish regional drought forums; and encourage development of state drought mitigation plans.
EVALUATION OF FOREST PRACTICES PRESCRIPTIONS FROM WASHINGTON'S WATERSHED ANALYSIS PROGRAM1
Authors: Collins Brian D. , Pess George R.
Published: June 2007

ABSTRACT: In Washington's watershed analysis program, scientific analysts identify watershed areas that are sensitive to forest practices. Land managers then develop watershed‐specific rules or ‘prescriptions” that condition forestry activities in those sensitive areas. Prescriptions are intended to provide greater protection than existing, or 'standard,” rules where necessary to avoid cumulative effects on public aquatic resources (fish habitat and public works). To assess strengths and opportunities for improving Washington's watershed analysis, we evaluate prescriptions from 20 analyses conducted from 1993 to 1995. We ask: (1) Are prescriptions watershed specific, compared to the general, or 'standard” forest practices rules? (2) Are prescriptions scientifically sound? (3) What promotes or limits development of watershed‐specific and scientifically sound prescriptions? We find: (1) Prescriptions tend to be similar to standard rules. One reason is that some components of the scientific assessment methodology incorporate approaches or assumptions from the standard rules, some of which are untested or unsupported. Another reason is that while other assessment methods are not patterned after the standard rules, resulting prescriptions do not necessarily integrate assessment information. (2) Many prescriptions lack a scientific rationale and are unproved in meeting their stated objectives. Despite the experimental nature of many prescriptions, they generally lack an evaluation component. (3) Washington's watershed analysis can be strengthened by: testing assumptions of some scientific assessment methods; basing prescriptions more rigorously on scientific assessment data and published scientific literature; and addressing uncertainty in whether prescriptions meet their objectives.
REGIONAL HYDROLOGIC RESPONSE OF LOBLOLLY PINE TO AIR TEMPERATURE AND PRECIPITATION CHANGES1
Authors: McNulty Steven G. , Vose James M. , Swank Wayne T
Published: June 2007

ABSTRACT: Large deviations in average annual air temperatures and total annual precipitation were observed across the southern United States during the last 50 years, and these fluctuations could become even larger during the next century. We used PnET‐IIS, a monthly time‐step forest process model that uses soil, vegetation, and climate inputs to assess the influence of changing climate on southern U.S. pine forest water use. After model predictions of historic drainage were validated, the potential influences of climate change on loblolly pine forest water use was assessed across the region using historic (1951 to 1984) monthly precipitation and air temperature which were modified by two general circulation models (GCMs). The GCMs predicted a 3.2°C to 7.2°C increase in average monthly air temperature, a ‐24 percent to + 31 percent change in monthly precipitation and a ‐1 percent to + 3 percent change in annual precipitation. As a comparison to the GCMs, a minimum climate change scenario using a constant 2°C increase in monthly air temperature and a 20 percent increase in monthly precipitation was run in conjunction with historic climate data. Predicted changes in forest water drainage were highly dependent on the GCM used. PnET‐IIS predicted that along the northern range of loblolly pine, water yield would decrease with increasing leaf area, total evapotranspiration and soil water stress. However, across most of the southern U.S., PnET‐IIS predicted decreased leaf area, total evapotranspiration, and soil water stress with an associated increase in water yield. Depending on the GCM and geographic location, predicted leaf area decreased to a point which would no longer sustain loblolly pine forests, and thus indicated a decrease in the southern most range of the species within the region. These results should be evaluated in relation to other changing environmental factors (i.e., CO2 and O3) which are not present in the current model.
MODELING HYDROLOGIC IMPACT OF WITHDRAWING THE GREAT LAKES WATER FOR AGRICULTURAL IRRIGATION1
Authors: He Chansheng
Published: June 2007

ABSTRACT: Growing interest in agricultural irrigation in the Great Lakes basin presents an increasing competition to other uses of Great Lakes water. This paper, through a case study of the Mud Creek Irrigation District in the Saginaw Bay basin, Michigan, evaluates the potential hydrologic effects of withdrawing water for agricultural irrigation to the Great Lakes. Crop growth simulation models for corn, soybeans, dry beans, and the FAO Penman method were used to estimate the difference in evapotranspiration rates between irrigated and nonirrigated identical crops, based on climate, soil, and management data. The simulated results indicate that an additional 70–120 mm of water would be evapotranspirated during the growing season from irrigated crop fields as compared to nonirrigated identical plantings. Dependent upon the magnitude of irrigation expansion, an equivalent of about 1 to 5 mm of water from Lakes Huron‐Michigan could be lost to the atmosphere. If agricultural irrigation further expands in the entire Great Lakes basin, the aggregated potential of water loss to the atmosphere through ET from all five Great Lakes would be even greater.
ASSESSING THE ACCURACY OF PALEOHYDROLOGIC INDICATORS, HARPERS FERRY, WEST VIRGINIA1
Authors: Fanok Susan Fuertsch , Wohl Ellen E.
Published: June 2007

ABSTRACT: Gaging stations established in 1895 at Millville, West Virginia and in 1882 at Harpers Ferry, West Virginia record flows ranging from a maximum of 6,509 m3s‐1 to a minimum of 2 m3s‐1. Historical and botanical indicators were used to extend the systematic flood record of the Shenandoah River for a study reach approximately 7.5‐km long. The long systematic record at the site provides a good opportunity to assess the accuracy of these sources of paleoflood information. Habitation of the area by settlers of European descent began in 1733, and historical flood records extend from 1748. Qualitative historical records from different sources were compared to yield the most complete flood history. The correlation between the various sources was extremely high. Botanical flood evidence preserved as adventitious sprouts, tree scars, and ring anomalies were documented in 37 trees. A flood chronology established from these data extended from 1896 to 1955. Botanical indicators provided an accurate, although incomplete, flood chronology. The ability to determine accurate flood stages from paleohydrologic indicators varied. Historical data yielded relatively accurate stages to within 1–2 m; only minimum values of flood stage could be obtained from botanical indicators. These results illustrate some of the strengths and weaknesses of paleohydrologic investigations in the eastern United States.