Showing papers on "Nonpoint source pollution published in 1993"
TL;DR: In this paper, the authors developed an indexing procedure for identifying soils, landforms, and management practices that could have unfavorable impacts on water bodies because of P movement, using the characteristic of the field site, including soil erosion rates, runoff, available P soil test levels, and fertilizer and organic P application rates.
Abstract: Nonpoint sources of P leaving the agricultural landscape can cause eutrophication of surface water and the associated growth of undesirable aquatic plants. USDA is developing an indexing procedure for identifying soils, landforms, and management practices that could have unfavorable impacts on water bodies because of P movement. This indexing procedure uses the characteristic of the field site, including soil erosion rates, runoff, available P soil test levels, and fertilizer and organic P application rates and methods to assess the degree of vulnerability of P movement from the site. A weighting procedure has been developed to include the various contributions each site characteristic may have. A summation of the products of the weighted site characteristic yields a site vulnerability rating [...]
480 citations
TL;DR: A comprehensive summary of North American studies that have examined the impacts of forest practices on each of these parameters of water quality is presented in this article, with highly variable results among regions in North America.
Abstract: Forest management activities may substantially alter the quality of water draining forests, and are regulated as nonpoint sources of pollution. Important impacts have been documented, in some cases, for undesirable changes in stream temperature and concentrations of dissolved oxygen, nitrate-N, and suspended sediments. We present a comprehensive summary of North American studies that have examined the impacts of forest practices on each of these parameters of water quality. In most cases, retention of forested buffer strips along streams prevents unacceptable increases in stream temperatures. Current practices do not typically involve addition of large quantities of fine organic material to streams, and depletion of streamwater oxygen is not a problem; however, sedimentation of gravel streambeds may reduce oxygen diffusion into spawning beds in some cases. Concentrations of nitrate-N typically increase substantially after forest harvesting and fertilization, but only a few cases have resulted in concentrations approaching the drinking-water standard of 10 mg of nitrate-NIL. Road construction and harvesting increase suspended sediment concentrations in streamwater, with highly variable results among regions in North America. The use of best management practices usually prevents unacceptable increases in sediment concentrations, but exceptionally large responses (especially in relation to intense storms) are not unusual.
259 citations
TL;DR: A study of the Mississippi River and its tributaries during July-August 1991, October-November 1991, and AprilMay 1992 has indicated that the entire navigable reach of the river is contaminated with a complex mixture of agrochemicals and their transformation products derived from nonpoint sources.
Abstract: A study of the Mississippi River and its tributaries during July-August 1991, October-November 1991, and AprilMay 1992 has indicated that the entire navigable reach of the river is contaminated with a complex mixture of agrochemicals and their transformation products derived from nonpoint sources. Twenty-three compounds were identified, including triazine, chloroacetanilide, thiocarbamate, phenylurea, pyridazine, and organophosphorus pesticides. The upper and middle Mississippi River Basin farm lands are major sources of herbicides applied to corn, soybeans, and sorghum. Farm lands in the lower Mississippi River Basin are a major source of rice and cotton herbicides
192 citations
TL;DR: In this article, the optimal trading ratio depends on the relative costs of enforcing point versus nonpoint reductions and on the uncertainty associated with nonpoint loadings, and the uncertainty does not imply a lower bound for the optimal trade ratio.
Abstract: In programs for trading pollution abatement between point and nonpoint sources, the trading ratio specifies the rate at which nonpoint source abatement can be substituted for point source abatement. The appropriate value of this ratio is unclear because of qualitative differences between the two classes of sources. To identify the optimal trading ratio, we develop and analyze a model of point/nonpoint trading. We find the optimal trading ratio depends on the relative costs of enforcing point versus nonpoint reductions and on the uncertainty associated with nonpoint loadings. The uncertainty does not imply a lower bound for the optimal trading ratio.
150 citations
TL;DR: The nature and significance of nonpoint sources of surface and groundwater pollution are examined in this paper, where examples are given from across the globe illustrating extensive economic, environmental, and human health damage from these diffuse sources.
127 citations
TL;DR: The authors evaluated the effects of conventional tillage, chisel-plow tillage and no tillage on the quality of runoff water from a Maury silt loam soil (fine, mixed, mesic Typic Paleudalf) near Lexington, Kentucky.
Abstract: As nonpoint source pollution of water becomes more evident, more concern is being focused on the effects of agricultural practices on water quality. This study evaluated the effects of conventional tillage (CT), chisel-plow tillage (CP), and no tillage (NT) on the quality of runoff water from a Maury silt loam soil (fine, mixed, mesic Typic Paleudalf) near Lexington, KY. The mean runoff rate, total runoff volume, mean sediment concentration, and total soil losses were significantly less for NT than for CP and CT [...]
125 citations
TL;DR: The roles soil testing programs can play in the development of nutrient management strategies, such as the P index, that are needed to minimize nonpoint source pollution by soil P are discussed.
Abstract: Many soils in the USA have extremely high soil test P levels from long-term fertilization and manuring. Sediment-bound and soluble P in runoff from these soils may contribute to eutrophication of surface waters. A field rating system, the «P index,» has been developed to assess the potential for soil P to contribute to nonpoint source pollution. A critical component in this index is soil test P. The primary objective of this paper is to discuss the roles soil testing programs can play in the development of nutrient management strategies, such as the P index, that are needed to minimize nonpoint source pollution by soil P. A survey of soil testing labs participating in four regional soil testing committees (North Central, Northeast, Mid-Atlantic, Southeast) was conducted in 1991-1992 to determine current approaches to soil P testing, the percentage of soils testing in the high or excessive range, and major concerns with high P soils [...]
116 citations
01 Sep 1993
TL;DR: In this article, the authors describe the paired watershed approach for conducting nonpoint source (NPS) water quality studies, which requires a minimum of two watersheds -control and treatment - and two periods of study -calibration and treatment.
Abstract: The purpose of the fact sheet is to describe the paired watershed approach for conducting nonpoint source (NPS) water quality studies. The basic approach requires a minimum of two watersheds - control and treatment - and two periods of study - calibration and treatment. The basis of the paired watershed approach is that there is a quantifiable relationship between paired water quality data for the two watersheds, and that this relationship is valid until a major change is made in one of the watersheds.
102 citations
TL;DR: In this article, alluvial groundwater adjacent to the main stem river is the principal nonpoint source of atrazine and deethylatrazine in the Cedar River of Iowa after the river has been in base flow conditions for 5 days.
Abstract: Alluvial groundwater adjacent to the main stem river is the principal nonpoint source of atrazine and deethylatrazine in the Cedar River of Iowa after the river has been in base flow conditions for 5 days. Between two sites along a 116-km reach of the Cedar River, tributaries contributed about 25% of the increase in the atrazine and deethylatrazine load, whereas groundwater from the alluvial aquifer contributed at least 75% of the increase in load. Within the study area, tributaries aggregate almost all of the discharge from tile drains, and yet the tributaries still only contribute 25% of the increase in loads in the main stem river. At an unfamned study site adjacent to the Cedar River, the sources of atrazine and deethylatrazine in the alluvial groundwater are bank storage of river water and groundwater recharge from areas distant from the river. Atrazine and deethylatrazine associated with bank storage water will provide larger concentrations to the river during early base flow conditions. After the depletion of bank storage, stable and smaller concentrations of atrazine and deethylatrazine, originating from groundwater recharge, continue to be discharged from the alluvial aquifer to the river; thus these results indicate that alluvial aquifers are an important nonpoint source of atrazine and deethylatrazine in rivers during base flow.
101 citations
01 Jan 1993
TL;DR: In the 1970s, large industrial and municipal emissions were the focus of first-generation environmental policies as mentioned in this paper, but with much success in cleaning up industrial sources, the focus has changed.
Abstract: Large industrial and municipal emissions were the focus of first-generation environmental policies of the 1970s. Twenty years later, with much success in cleaning up industrial and municipal sources, the focus has changed. The problems of the moment include hazardous wastes, solid wastes, auto pollution, nutrient pollution, pesticide pollution, and sedimentation. These problems, by and large, are caused by many small polluters—such as users of weed sprays, motorists, farmers, and generators of household trash.
96 citations
TL;DR: In this article, three NPS pollution models that were integrated with a GIS were used to simulate a watershed response to a series of rainfall events, and simulated responses matched the observed results reasonably well considering model inputs were estimated from base GIS data.
TL;DR: In this paper, the effects of cell size selection through a sensitivity analysis of input parameters for the agricultural nonpoint source pollution model (AGNPS) using a GIS for a small research watershed.
Abstract: Nonpoint‐pollution models estimate loadings of chemicals, sediment, and nutrients that degrade water quality. Before controls can be implemented, location and severity of pollution must be identified in the watershed basin. Geographic information systems (GISs) are computer‐automated, data management systems simplifying the input, organization, analysis, and mapping of spatial information. Because nonpoint‐pollution models simulate distributed watershed basin processes, a heterogeneous and complex land surface must be divided into computational elements such as grid cells. Model parameters can be derived from each grid cell directly from maps using GIS. Cell size selection, if arbitrarily determined though, yields ambiguous if not erroneous results. This paper investigates the effects of cell size selection through a sensitivity analysis of input parameters for the nonpoint‐pollution model, Agricultural Nonpoint Source Pollution Model (AGNPS), using a GIS for a small research watershed. Model grid‐cell si...
TL;DR: In this paper, a metamodel summarizes the input-output relationships in a complex simulation model designed to mimic actual processes such as groundwater leaching to predict groundwater and surface water concentrations of major corn and sorghum herbicides in the Corn Belt and Lake States regions of the United States.
Abstract: Complex mathematical simulation models are generally used for quantitative measurement of the fate of agricultural chemicals in soil. But it is less efficient to use them directly for regional water quality assessments because of the large number of simulations required to cover the entire region and because the entire set of simulation runs must be repeated for each new policy. To make regional water quality impact assessment on a timely basis, a simplified technique called metamodeling is suggested. A metamodel summarizes the input-output relationships in a complex simulation model designed to mimic actual processes such as groundwater leaching. Metamodels are constructed and validated to predict groundwater and surface water concentrations of major corn and sorghum herbicides in the Corn Belt and Lake States regions of the United States. The usefulness of metamodeling in the evaluation of agricultural nonpoint pollution policies is illustrated using an integrated environmental economic modeling system. For the baseline scenario, we estimate that 1.2% of the regional soils will lead to groundwater detection of atrazine exceeding 0.12 Mg/L, which compares well with the findings of an Environmental Protection Agency monitoring survey. The results suggest no-till practices could significantly reduce surface water concentration and a water quality policy, such as an atrazine ban, could increase soil erosion despite the conservation compliance provisions.
01 Jan 1993
Posted Content•
TL;DR: In this article, a simplified and robust technique, metamodeling, is suggested to evaluate regional water quality in relation to management practices, including no-till practices and agricultural economic decision-making.
Abstract: Informed debate on agricultural nonpoint pollution requires evaluation of regional water quality in relation to management practices. It is prohibitive, in terms of cost and time, to run the site-specific process models for regional policy analysis. Therefore, a simplified and robust technique--metamodeling--is suggested to evaluate regional water quality. Data from an experimentally designed simulation of complex surface water and groundwater process models, PRZM and STREAM, are used to develop statistically validated metamodels. The estimated metamodels were integrated with a regional agricultural economic decision making model to evaluate the surface water and groundwater loadings of 16 major corn and sorghum herbicides. Spatial probability distributions are derived for herbicide concentrations exceeding the toxicity-weighted benchmark from the EPA. We estimate that 1.2 percent of the regional soils will lead to groundwater detection of atrazine exceeding 0.12 ?/L, which compares well with the findings of the EPA's groundwater monitoring survey. We find no-till practices to significantly reduce the surface water concentration of atrazine and other herbicides with less impact on groundwater contamination suggesting indirect gains to soil conservation policies. But we also note that an atrazine ban could lead to increased soil erosion, even with the conservation compliance provisions fully incorporated.
01 Jan 1993
TL;DR: In this paper, the authors present a model for analyzing the environmental effects of agricultural policy on nonpoint-source pollution in California's San Joaquin River Basin, using economic and physical models.
Abstract: Foreword. 1. Information problems in the Design of Nonpoint Source Pollution J.B. Braden, K. Segerson. 2. Differences in the Transaction Costs of Strategies to Control Agricultural Offsite and Undersite Damages K.W. Easter. 3. Regulatory/Economic Instruments for Agricultural Pollution: Accounting for Input Substitution M.E. Eiswerth. 4. Nonpoint Source Pollution Control, Information Asymmetry, and the Choice of Time Profile for Environmental Fees C. Dosi, M. Moretto. 5. Point/Nonpoint Source Trading for Controlling Pollutant Loadings to Coastal Waters: A Feasibility Study D. Letson, S. Crutchfield, A. Malik. 6. Integrating Economic and Physical Models for Analyzing Environmental Effects of Agricultural Policy on nonpoint-Source Pollution J.M. Antle, S.M. Capalbo. 7. Data Requirements for Modeling and Evaluation of National Policies Aimed at Controlling Agricultural Sources of Nonpoint Water Pollution R.A. Shoemaker, D.E. Ervin, M. Caswell. 8. Analysis of Policy Options for the Control of Agricultural Pollution in California's San Joaquin River Basin M. Weinberg, C. Kling, J. Wilen. 9. Regional Modeling and Economic Incentives to Control Darinage Pollution A. Dinar, E.T. Loehman, M.P. Aillery, M.R. Moore, R.E. Howitt, S.A. Hatchett. 10. Florida's Experience with managing Nonpoint Source Phosphorus Runoff into Lake Okeechobee W.G. Boggess, E.G. Flaig, C.M. Fonyo. 11. Subsidizing Agricultural Nonpoint Source Pollution Control: Targetting Cost Sharing and Technical Assistance E. Lichtenberg, I.E. Strand, Jr., B.V. Lessley. 12. Reforming Nonpoint Pollution Policy J.F. Shogren.
TL;DR: In this paper, the authors show that the increasing amount of marginal farmland being put into production could have significant water quality consequences because marginal lands are generally steeper, have more erodible soils, poorer drainage, and require more fertilizer than prime farmlands.
Abstract: California’s population increased 25% between 1980 and 1990, resulting in rapid and extensive urbanization. Of a total 123,000 ha urbanized in 42 of the state’s 58 counties between 1984 and 1990, an estimated 13% occurred on irrigated prime farmland, and 48% on wildlands or fallow marginal farmlands. Sixty-six percent of all new irrigated farmland put into production between 1984 and 1990 was of lesser quality than the prime farmland taken out of production by urbanization. Factors dictating the agricultural development of marginal farmlands include the availability and price of water and land, agricultural commodity prices, and technical innovations such as drip irrigation systems that impact the feasibility and costs of production. The increasing amount of marginal farmland being put into production could have significant water quality consequences because marginal lands are generally steeper, have more erodible soils, poorer drainage, and require more fertilizer than prime farmlands. Although no data exist to test our hypothesis, and numerous variables preclude definitive predictions, the evidence suggests that new irrigated marginal lands can increase nonpoint source (NPS) pollution for a given size area by an order of magnitude in some cases.
Journal Article•
TL;DR: In this paper, the authors used the Erosion Productivity Impact Calculator (EPIC) model to simulate responses of soil erosion and nutrient exports to several different tillage and crop rotation practices.
Abstract: The 1987 National Resources Inventory (NRI) was used to provide a random sample of 100 Illinois cropland sites growing corn and soybeans. These were used with the Erosion Productivity Impact Calculator (EPIC) model to simulate responses of soil erosion and nutrient exports to several different tillage and crop rotation practices. The NRI and other data sources were used for site specific characterizations that reflected the multidimensional variability in site conditions in Illinois. Four alternative management schemes were simulated for each site: continuous corn and soybean/corn rotations under conventional tillage and no-till. Average crop yields varied little under the four management schemes and closely corresponded to expected yields from the SCS Soils-5 Soil Interpretation Records. However, no-till significantly reduced soil erosion rates and loss of soil organic carbon compared to conventional tillage. This reduced erosion under no-till also led to reduced losses of nitrogen (N) and phosphonw (P) in eroded soil. Percolation belous the root zone represented the greatest N export and is of concern for the issue of groundwater contamination in this region. Nitrate N concentrations in percolate substantially exceeded the drinking water standard of 10 mg/l. Soybean/corn rotations generally had 10–30 percent lower soluble N losses in surface runoff, subsurface flow, and percolation than the corresponding conventional tillage or no-till practices under continuous corn. No-till resulted in a 24 percent increase in soluble N runoff losses compared to conventional tillage in soybeadcorn rotations. P losses in surface runoff were larger under no-till, likely as a result of the lack of immediate incorporation of surface P fertilizer into the soil. The model predictions for changes in soil erosion and N and P losses under different management practices were in line with measured changes in site-specific field studies under similar conditions. Our study results take into account the effect of site-to-site variability on the responses and the relative frequency of different site conditions state-wide. This indicates the potential magnitude for changes in nonpoint source pollution by sediment, N, and P state-wide by adoption of alternative corn and soybean tillage and rotation schemes.
TL;DR: The Rio Grande Valley National Water Quality Assessment study unit encompasses about 45,700 square miles in Colorado, New Mexico and Texas upstream from the gaging station Rio Grande at El Paso, Texas, and includes surface-water closed basins east of the Continental Divide in New Mexico, and the San Luis Closed Basin in Colorado.
Abstract: The Rio Grande Valley National Water-Quality Assessment study unit encompasses about 45,700 square miles in Colorado, New Mexico, and Texas upstream from the gaging station Rio Grande at El Paso, Texas, and includes surface-water closed basins east of the Continental Divide in New Mexico, and the San Luis Closed Basin in Colorado. The mean annual precipitation ranges from less than 6 to more than 50 inches; potential evapo-transpiration ranges from less than 35 to more than 80 inches per year. Land use is mainly rangeland, forest land, and cropland. Total irrigated acreage in 1990 was about 914,000 acres and water use was about 3,410,000 acre-feet. Two structural settings are found in the study unit: alluvial basins and bedrock basins. The alluvial basins can have through-flowing surface water or be closed basins. The discussion of streamflow and water quality for the surface-water system is based on four river reaches for the 750 miles of the main stem. The quality of the ground water is affected by both natural process and human activities and by nonpoint and point sources. Nonpoint sources for surface water include agriculture, hydromodification, and mining operations; point sources are mainly discharge from wastewater treatment plants. Nonpoint sources for ground water include agriculture and septic tanks and cesspools; point sources include leaking underground storage tanks, unlined or manure-lined holding ponds used for disposal of dairy wastes, landfills, and mining operations.
Book•
01 Jan 1993
TL;DR: Evaluating the role of created and natural wetlands in Controlling Nonpoint Source Pollution (R.K. Olson), the authors proposes a model for nonpoint source pollution control in the watershed.
Abstract: Evaluating the Role of Created and Natural Wetlands in Controlling Nonpoint Source Pollution (R.K. Olson). Introduction to Nonpoint Source Pollution and Wetland Mitigation (L.A. Baker). Landscape Design and the Role of Created, Restored, and Natural Riparian Wetlands in Controlling Nonpoint Source Pollution (W. MiLsch). Designing Constructed Wetlands Systems to Treat Agricultural Nonpoint Source Pollution (D. Hanirner). Developing Design Guidelines for Constructed Wetlands to Remove Pesticides from Agricultural Runoff (Q.H. Rodgers, jr. and A. Dunn). Ancillary Benefits and Potential Problems with the Use of Wetlands for Nonpoint Source Pollution Control (R. Knight). Regulations and Policies Relating to the Use of Wetlands for Nonpoint Source Pollution Control (S. Fields). The Role of Wetland Water Quality Standards in Nonpoint Source Pollution Control Strategies (D. Robb). Recommendations for Research to Develop Guidelines for the Use of Wetlands to Control Rural Nonpoint Source Pollution (A. van der Valk and R. Jolly). Research and information Needs Related to Nonpoint Source Pollution and Wetlands in the Watershed: An EPA Perspective (B. Ethridge and R.K. Olson). Federal Programs for Wetland Restoration and Use of Wetlands for Nonpoint Source Pollution Control (G. Whitaker and C.R. Terrell).
01 Jan 1993
TL;DR: In this paper, a comprehensive review of current state and federal programs for forest areas reveals a substantial increase in agency water quality protection activities and that BMP use is increasing and that such use typically maintains water quality within standards.
Abstract: Recent federal legislation strengthened nonpoint source pollution regulations and helped to support and standardize pollution control efforts. A comprehensive review of current state and federal programs for forest areas reveals a substantial increase in agency water quality protection activities. These new efforts emphasize monitoring to assess the use and effectiveness of best management practices (BMPs). Recent monitoring reveals that BMP use is increasing and that such use typically maintains water quality within standards. However, information is generally lacking about the cost effectiveness of BMP programs. Carefully designed and executed monitoring is the key to better specification of BMPs and more cost effective water quality protection. (KEY TERMS: water quality; nonpoint source pollution; water law; watershed management; forestry; best management practices.)
TL;DR: In this paper, a case study was carried out in the small watershed of Chaohu Lake, where a scattered multi-pond system, as a part of the land-inland water ecotone, was found to be a good protective zone in the management of the lake.
Abstract: A study was carried out in the small watershed of Chaohu Lake, where a scattered multi-pond system, as a part of the land-inland water ecotone, was found to be a good protective zone in the management of the lake. This multi-pond system can effectively reduce the non-point source load of nutrients, such as phosphorus and nitrogen from runoff water, and filter out sediments before they reach the lake. There are 150 artificial ponds in this small watershed, covering a surface area of 35.54 ha, which represents just under 5% of the whole catchment area. The nutrient retention in the first 9 months of the dry year 1988 was more than 90%. This multi-pond system needs low capital cost and energy consumption for maintenance, and is suitable for irrigation and drainage, while it recycles water and nutrients within the terrestrial agroecosystem. As a result of this case study, a multipond system is being proposed as part of a long term management strategy for the watershed.
TL;DR: In this article, the magnitude and water quality implications of nonpoint source phosphorus loadings to Owasco Lake (New York) are evaluated through the application of a methodology which links geographic characteristics, longterm average runoff loads and a set of critical lakewide water quality response parameters.
TL;DR: In this paper, an empirical non-point source loading model driven by land use was used to estimate pollutant loadings of priority pollutants in urban nonpoint source pollution and the development of a pollution control strategy.
Abstract: A geographic information system (GIS) was a useful aid in the assessment of urban nonpoint source pollution and the development of a pollution control strategy. The GIS was used for data integration and display, and to provide data for a nonpoint source model. An empirical nonpoint source loading model driven by land use was used to estimate pollutant loadings of priority pollutants. Pollutant loadings were estimated at fine spatial resolution and aggregated to storm sewer drainage basins (sewersheds). Eleven sewersheds were generated from digital versions of sewer maps. The pollutant loadings of individual land use polygons, derived as the units of analysis from street blocks, were aggregated to get total pollutant loadings within each sewershed. Based on the model output, a critical sewershed was located. Pollutant loadings at major sewer junctions within the critical sewershed were estimated to develop a mitigation strategy. Two approaches based on the installation of wet ponds were investigated - a regional approach using one large wet pond at the major sewer outfall and a multisite approach using a number of smaller sites for each major sewer junction. Cost analyses showed that the regional approach would be more cost effective, though it would provide less pollution control.
01 May 1993
TL;DR: One of the TVA's major goals is cleanup and protection of the waters of the Tennessee River system as discussed by the authors, and TVA began demonstration of the constructed wetlands technology in 1986 as an alternative to conventional, mechanical processes, especially for small communities.
Abstract: One of the Tennessee Valley Authority`s (TVA`s) major goals is cleanup and protection of the waters of the Tennessee River system. Although great strides have been made, point source and nonpoint source pollution still affect the surface water and groundwater quality in the Tennessee Valley and nationally. Causes of this pollution are poorly operating wastewater treatment systems or the lack of them. Practical solutions are needed, and there is great interest and desire to abate water pollution with effective, simple, reliable and affordable wastewater treatment processes. In recognition of this need, TVA began demonstration of the constructed wetlands technology in 1986 as an alternative to conventional, mechanical processes, especially for small communities. Constructed wetlands can be downsized from municipal systems to small systems, such as for schools, camps and even individual homes.
TL;DR: The authors examined the public and private sector costs and social benefits associated with North Carolina's program and provided general policy guidance on questions relating to the likely burden the new best management practices will have on the development industry, the likely costs and benefits of such a program, and the feasibility of running a program on a cost recovery basis.
Abstract: The EPA’s new nonpoint source pollution control requirements will soon institutionalize urban erosion and sediment pollution control practices nationwide. The public and private sector costs and social benefits associated with North Carolina’s program (one of the strongest programs in the country in terms of implementation authority, staffing levels, and comprehensiveness of coverage) are examined to provide general policy guidance on questions relating to the likely burden the new best management practices will have on the development industry, the likely costs and benefits of such a program, and the feasibility of running a program on a cost recovery basis. We found that urban erosion and sediment control requirements were not particularly burdensome to the development industry (adding about 4% on average to development costs). Public-sector program costs ranged between $2.4 and $4.8 million in fiscal year 1989. Our contingent valuation survey suggests that urban households in North Carolina are willing to pay somewhere between $7.1 and $14.2 million a year to maintain current levels of sediment pollution control. Our benefit-cost analysis suggests that the overall ratio is likely to be positive, although a definitive figure is elusive. Lastly, we found that several North Carolina localities have cost recovery fee systems that are at least partially self-financing.
TL;DR: The U.S. Geological Survey, in cooperation with the Wisconsin Department of Natural Resources, monitored water quality in the Black Earth Creek watershed in southern Wisconsin from October 1984 through September 1986 (pre-BMP conditions) and reported statistically significant differences in storm mass transport of suspended sediment and ammonia nitrogen at Brewery Creek as discussed by the authors.
TL;DR: The Rural Clean Water Program (RWC) is a 10-15-year experimental program designed to control agricultural NPS pollution in rural watersheds as mentioned in this paper, where the water quality and land treatment data bases should be temporally related.