Non-point Source Pollution Management Research Articles

Identification of critical source areas for nonpoint source pollution in the Danjiangkou Reservoir Basin, China

ABSTRACTZhuang Y, Zhang L, Du Y, Yang W, Wang L, Cai X. 2016. Identification of critical source areas for nonpoint source pollution in the Danjiangkou Reservoir Basin, China. Lake Reserve Manage. 32:341–352.Danjiangkou Reservoir is an important water source for the middle route of the South-to-North Water Diversion Project in China. Water quality is crucial for this project, and the identification of critical source areas (CSAs) plays a significant role in nonpoint source (NPS) pollution control. The load–area curve based on the Export Empirical Model was used to quantitatively classify CSAs of NPS pollution in the Danjiangkou Reservoir Basin as CSAs, sub-CSAs, and non-CSAs. About 70% of loads were from 30% of the basin. In CSAs, 45.4% of total nitrogen (TN) loads and 48.0% of total phosphorus (TP) loads were from 14.5% and 13.3% of the basin, respectively; in sub-CSAs, 19.7% of TN loads and 18.3% of TP loads were from 14.5% and 13.3% of the basin, respectively. CSAs of both TN and TP loads were mainly from areas near the reservoir, which are subject to severe soil erosion and large runoff discharge. In the Danjiangkou Reservoir Basin, we recommend a CSAs→sub-CSAs→non-CSAs hierarchical control in the NPS pollution management plan specifying that sloping farmland in Xichuan and Yunxian counties should be preferentially treated. The load–area curve offers a new way of identifying CSAs of NPS pollution and helps to establish effective control measures for NPS pollution.

Policy tools for agricultural nonpoint source water pollution control in the U.S. and E.U.

Purpose – In the USA and Europe, agricultural nonpoint source (NPS) pollution continues to be among the chief impediments to achieving water quality standards. While the implementation of technology-based water pollution control tools has resulted in evident point source pollution abatement, NPSs continue to threaten surface water and groundwater. The purpose of this paper is to draw from environmental policy literature to identify regulatory tools and management approaches that specifically target agricultural NPS pollution and the factors that drive or impede their implementation and enforcement. This paper utilizes the policy tool framework to help characterize the widespread policy problem, distinguishing its unique set of hurdles from other environmental problems. Design/methodology/approach – Discussion of agricultural NPS pollution management approaches is based on a thorough review of relevant environmental policy and environmental economic literature as well as case studies from the USA and Europe. Analysis is based on the policy tool framework. Findings – This study finds that controlling numerous diffuse sources of agricultural pollution requires an integrated approach that utilizes river basin management and a mix of policy instruments. Additionally, findings suggest that transitioning from voluntary mechanisms to more effective instruments based on measurable water quality performance relies predominantly on three factors: first, more robust quality monitoring data and models; second, local participation; and third, political will. Originality/value – This research provides important information for regional and national policymakers in areas where there is increasing pollution and regulatory mandates. Identifying conditions of effective water quality policy is applicable and will be of direct use to agencies charged with pollution control.

Identifying organic matter sources using isotopic ratios in a watershed impacted by intensive agricultural activities in Northeast China

Knowledge about the origin and variation of OM (organic matter) pools in a receiving river might provide a basis for addressing non-point sources of pollution resulting from intensive agricultural activity. In this study, an isotopic approach (δ13C, δ15N and C/N ratios) was used to identify potential OM sources and C and N cycle processes occurring in the Abujiao River watershed located in the Sanjiang Plain. A Bayesian model (stable isotope analysis in R, SIAR) was utilized to apportion the contributions of potential sources. In this watershed, isotopic ratios of δ13C ranged from −30.62‰ to −23.71‰ and from −28.22‰ to −23.98‰ in particulate organic matter (POM) and sedimentary organic matter (SOM), respectively. Slightly lower δ15N values (3.12±4.12‰ in POM; 3.7±2.42% in SOM) and C/N ratios (6.62±5.28 in POM; 10.73±6.58 in SOM) were found in SOM pools. Considerable spatio-temporal variability of the organic carbon and nitrogen isotopic ratios was present in the POM pool, which was controlled by storms and land use. The unusually low δ15N-POM values accompanied by high chlorophyll-a concentrations suggested that an isotopic fractionation effect caused by phytoplankton existed in the POM pool. However, isotopic characteristics indicated that the isotopic fractionation was absent in the SOM pool. SIAR modeling result showed that source contributions differed significantly among different sampling periods. During storms, ”soil OM” was the major source (accounting for 45.50%) in the POM pools. During other periods, effluent detritus and phytoplankton sources were predominant in the downstream region. Compared with POM, almost half of SOM came from terrestrial sources, and the effluent detritus and “soil OM” sources predominated in the SOM pool. This study suggested that assessment of behaviors and sources of OM could lead to the implementation of effective non-point source pollution reduction strategies and management practices for protecting water quality.

Shade tree cover criteria for non-point source pollution control in the Rainforest Alliance coffee certification program: A snapshot assessment of Costa Rica's Tarrazú coffee region

Management of non-point source pollution is of great importance in the context of coffee agriculture, as this land use often coincides with headwater streams that influence water quality at the basin scale. Sustainability certification programs, such as the Rainforest Alliance (RA), provide management guidelines that promote non-point source pollution control in coffee. One of these practices is the maintenance of shade trees within farms, required by RA at a minimum of 40% shade tree cover. Here we assess the effectiveness of this practice in Tarrazú, a high elevation coffee growing region in Costa Rica. We monitored indicators of non-point source pollution in streams with both high and low shade tree cover. Streams with High Shade Tree Cover (HSTC, N=5 subwatersheds) had 35–55% cover, approximating or exceeding the RA recommendation of at least 40%; and streams with Low Shade Tree Cover (LSTC, N=5 subwatersheds), had 18–31% cover. We monitored the ten study streams during the dry (April & December), transition (July), and peak (October) rainfall seasons of 2013, and compared responses using t-tests. We found support for the effectiveness of shade tree cover in controlling non-point source pollution: HSTC streams had significantly (p=0.042) lower mean annual turbidity and significantly (p=0.004) lower turbidity during the transition season. HSTC streams also had significantly (p=0.05) lower conductivity values during the transition period, although this trend was weaker through the year. Subwatersheds with HSTC streams were characterized by a higher percentage of RA-certified coffee than LSTC streams. Our study provides evidence of the benefits of RA shade tree cover criteria for managing water quality within high elevation tropical agro-ecosystems, especially if implemented at the watershed scale. These results contribute to our understanding of the role of agroforestry certification on tropical ecosystem conservation, and are the first account of the effectiveness of a specific coffee certification guideline on non-point source pollution control.

수질개선을 위한 축산계 오염물질 관리방안에 대한 고찰

In recently, the Korea government is concerning on non-point source pollution management to improve water quality. The objective of this paper is to investigate the improvement measurement for management of livestock wastes. As a result, we find that the National Pollution Source Survey is necessary to establish the unified database system with the Korea Statistics(KOSAT) in order to minimize the difference between relevant data. The investigation for environmental impact of livestock manure should be supported the designation of control areas and establishment of the technical guidelines including target material, monitoring site, standard method, etc. In addition, it should be followed by appropriate nutrient recycling and proper fertilizer usage based on social consultation and cost-benefit analysis.

Prioritizing subwatersheds for non-point source pollution management in Saemangeum watershed using AHP technique

The objective of this study was to investigate non-point sources (NPS) pollution and prioritize management areas affected by NPS pollution in the Saemangeum Watershed. AHP (Analytical Hierarchy Process) technique was selected to prioritize sub-watersheds for effectively managing NPS pollution in this study areas. Generation properties of NPS pollution, discharge properties of NPS pollution, and runoff properties of NPS pollution were selected and set for AHP. Weighted descriptors including indicators like numbers of livestock, land- and livestock-system loads, rainfall, and impervious area ratio were generalized from 0 to 1 and multiply each index based on screened 17 survey data. The results were visualized as maps which enable resource managers to identify sub-watersheds for effective improving water quality. The sub-watersheds located in Gongdeok-Myeon, Yongji-Myeon, Hwangsan-Myeon of Gimje-Si were selected for managing NPS pollution control areas. This result presented that these sub-watershed are more affected by the pollution from livestock-system than from land-system. The finding from this study can be used to screen sub-watersheds that need further assessment by managers and decision-makers within the study area.

Characterization of Stormwater Runoff from a Light Rail Transit Area.

The monitoring of stormwater runoff from Light Rail Transit (LRT) facilities is insufficient in many regions around the world. In this study, runoff quality and quantity were monitored during operational and non-operational LRT phases during 2010-2013. The event mean concentration (EMC) of pollutants showed little statistical variability during both phases. The antecedent dry day (ADD) showed a strong to moderate positive correlation with most pollutant EMCs during the non-operational phase. The existence and magnitude of the first flush from LRT runoff was found to be similar to those from other transportation land uses. The comparison of LRT runoff data with an adjacent road bridge site showed that the pollutant EMC and unit load were 2 to 9 times higher from the road bridge. It was suggested that LRT automated operation and the elevated track makes this transportation mode a viable option for the management of non-point source pollution.

새만금 비점오염원 관리지역에서의 목표설정 및 달성도 평가방법론 연구

In this study, methods using LDC (Load Duration Curve) and watershed model were suggested to develope management targets and evaluate target achievement for non-point source pollution management considering watershed and runoff characteristics and possibility for achievement of target. These methods were applied for Saemangeum watershed which was designated as nonpoint source pollution management area recently. Flow duration interval of 5 to 40% was selected as flow range for management considering runoff characteristics and TP was selected as indicator for management. Management targets were developed based on scenarios for non-point source pollutant reduction of management priority areas using LDC method and HSPF model which was calibrated using 4 years data (2009~2012). In the scenario of LID, road sweeping and 50% reduction in CSOs and untreated sewage at Jeonju A20 and 30% reduction in fertilizer and 50% in livestock NPS at Mankyung C03, Dongjin A14 and KobuA14, management targets for Mangyung bridge, Dongjin bridge, Jeonju stream and Gunpo bridge were developed as TP 0.38, 0.18, 0.64 and 0.16 mg/L respectively. When TP loads at the target stations were assumed to have been reduced by a certain percentage (10%), management targets for those target stations were developed as TP 0.35, 0.17, 0.60 and 0.15 mg/L respectively. The result of this study is expected to be used as reference material for management master plan, implementation plan and implementation assessment for non-point source management area.

Detection of sensitive soil properties related to non-point phosphorus pollution by integrated models of SEDD and PLOAD

Effectively identifying soil properties in relation to non-point source (NPS) phosphorus pollution is important for NPS pollution management. Previous studies have focused on particulate P loads in relation to agricultural non-point source pollution. In areas undergoing rapid urbanization, dissolved P loads may be important with respect to conditions of surface infiltration and rainfall runoff. The present study developed an integrated model for the analysis of both dissolved P and particulate P loads, applied to the Meiliang Bay watershed, Taihu Lake, China. The results showed that NPS P loads up to 15kg/km2 were present, with particulate P loads up to 13kg/km2. The highest loads were concentrated in the southeastern region of the watershed. Although particle P was the main contributor to NPS P loads state, the contribution of dissolved P was significant, especially in sub-basins with significant amount of artificial land cover. The integration of dissolved P and particulate P loads provided more accurate evaluation of NPS P pollution. NPS P loads were found to correspond to specific soil properties. Soil organic matter and total nitrogen were shown to influence dissolved P loads, while total phosphorus and soil particle composition proportion were more closely related to particulate P loads.

Agricultural BMP Effectiveness and Dominant Hydrological Flow Paths: Concepts and a Review

AbstractWe present a conceptual framework that relates agricultural best management practice (BMP) effectiveness with dominant hydrological flow paths to improve nonpoint source (NPS) pollution management. We use the framework to analyze plot, field and watershed scale published studies on BMP effectiveness to develop transferable recommendations for BMP selection and placement at the watershed scale. The framework is based on the location of the restrictive layer in the soil profile and distinguishes three hydrologic land types. Hydrologic land type A has the restrictive layer at the surface and BMPs that increase infiltration are effective. In land type B1, the surface soil has an infiltration rate greater than the prevailing precipitation intensity, but there is a shallow restrictive layer causing lateral flow and saturation excess overland flow. Few structural practices are effective for these land types, but pollutant source management plans can significantly reduce pollutant loading. Hydrologic land type B2 has deep, well‐draining soils without restrictive layers that transport pollutants to groundwater via percolation. Practices that increased pollutant residence time in the mixing layer or increased plant water uptake were found as the most effective BMPs in B2 land types. Matching BMPs to the appropriate land type allows for better targeting of hydrologically sensitive areas within a watershed, and potentially more significant reductions of NPS pollutant loading.

Determination of the first-flush criteria from railway bridge area

The management of non-point source pollution is necessary, because it may degrade the water quality. The railway facility areas located in South Korea are considered significant non-point source pollution. Therefore, the method of managing non-point source pollution in the railway areas is crucial. This study was conducted to quantify the first flush in the railway bridge area and to suggest the method of reducing the pollution level of the facilities that create non-point source pollution. The first-flush criteria are analyzed using the volume ratio method, the dynamic event mean concentration method, and the mass first-flush ratio method. As a result of an effective rainfall analysis, the first-flush effective rainfall depths were determined to be 8.4mm in the concrete roadbed area and 16.5mm in the gravel roadbed area. These first-flush rainfall depths are greater than the sizing criteria (5 mm) of best management practices (BMPs) for capturing first flush in South Korea. Thus, a rigorous rainfall-runoff management is required in the gravel roadbed area. This study implies that BMP must be properly installed upon consideration on the characteristics of the railway facility areas, which have rarely received attention as a significant non-point source as opposed to paved urban areas such as parking lots and roadways.

Policies and Research Trends on Non-point Source Pollution Management in Korea

Policies and Research Trends on Non-point Source Pollution Management in Korea

Using hyper-spectral indices to detect soil phosphorus concentration for various land use patterns.

The management of nonpoint source pollution requires accurate information regarding soil phosphorus concentrations for different land use patterns. The use of remotely sensed information provides an important opportunity for such studies, and the previous studies showed that soil phosphorus shows no clear spectral response feature, while the phosphorus concentrations can be indirectly detected from the normalised difference vegetation indices (NDVI). Therefore, this study uses an optimised index in the RED and near-infrared (NIR) wavelengths to estimate total phosphorus and Olsen-P concentrations. The prediction accuracy is not entirely satisfactory with respect to a mixed land use dataset in which the determination coefficient was maintained at approximately 0.6, with particularly poor performance obtained for forest land group. However, the prediction accuracy increases markedly with the separation of samples into broad land use categories, even the R(2) was exceeded 0.8 for tea plantation group. The soil phosphorus prediction effect showed obvious variance for different land use patterns, which was related to vegetation growth conditions and critical soil properties including soil organic matter and mechanical composition.

수질오염총량관리제의 합리적인 시행을 위한 비점오염원관리 개선방안 - 비점오염원 관리지역 선정 및 비점오염물질 관리를 중심으로 -

For effective implementation of total maximum daily load (TMDL), this study presented the improving plans of nonpoint source pollution management including the classification of non-point source pollution, calculation of non-point source pollution load (generated, discharged), selection of non-point source pollution management regions and management of non-point source pollutant. First of all, the definition of point source pollution and non-point source pollution based on the legal and scientific viewpoint should be precisely classified and managed. Especially, the forest, grassland and river without occurrence of environmental damage by activity of business and human should be separately classified natural background pollutants. The unit for generated and discharged non-point source pollution should be preferentially changed according to actual condition of watershed. The calculation methods of generated and discharged non-point source pollution should be corrected consideration on the amount and duration of rainfall. While the TMDL is implemented, non-point source pollution management regions should be selected in the watersheds exceed the targeted water quality standards by the rainfall. The non-point source pollution management regions should be selected in the minimal regions where have high values of discharged non-point source pollution density in the urban area, farmland and site area except forest, grassland in the whole watershed. The non-point source pollutant treatment facilities, which take into consideration non-point source pollution load per unit area, duration of the excess concentration, realizable possibility of treatment, effectiveness of treatment cost versus point source pollutant, should be established in the regions with a large generated non-point source pollution load and a high concentration of water quality exceed the targeted water quality standards by the rainfall.

Identifying non-point source priority management areas in watersheds with multiple functional zones

The concept of water functional zones promotes the comprehensive supervision and scientific oversight of non-point source (NPS) pollution at the watershed scale. Therefore, understanding the spatial distributions and temporal trends in watershed priority management areas (PMAs) is important in the study and efficient management of NPS pollution. However, no comprehensive studies of PMAs have been conducted to protect water quality effectively in watersheds with multiple water functional zones. In this study, a new framework is presented that quantifies the perturbations of multiple spatial assessment units to the quality of nearby water bodies in various water functional zones. This innovative approach, which combines the Soil and Water Assessment Tool (SWAT) and statistical analysis, was applied to characterize multiple-level PMAs with a case study of the Daning River watershed in China. Based on the results, the advantage of this new framework is better suited to downstream areas, particularly in dry periods and severely polluted watersheds. This paper reinforces the view that the concept of zoning should be taken seriously in the framework of PMAs targeting. From the aspect of watershed management, these new PMAs can offer an optimal strategy for locating comprehensive and cost-effective management practices at the watershed scale, particularly in large watersheds or long river systems.

비점오염원 관리지역(소양호) 목표수질 달성도 평가

The Ministry of Environment (MOE) has made more effort in managing point source pollution rather than in nonpoint source pollution in order to improve water quality of the four major rivers. However, it would be difficult to meet water quality targets solely by managing the point source pollution. As a result of the comprehensive measures established in 2004 under the leadership of the Prime Minister's Office, a variety of policies such as the designation of control areas to manage nonpoint source pollution are now in place. Various action plans to manage nonpoint source pollution have been implemented in the Soyang-dam watershed as one of the control areas designed in 2007. However, there are no tools to comprehensively assess the effectiveness of the action plans. Therefore, this study would assess the action plans (especially, BMPs) designed to manage Soyang-dam watershed with the WinHSPF and the CE-QUAL-W2. To this end, we simulated the rainfall-runoff and the water quality (SS) of the watershed and the reservoir after conducting model calibration and the model validation. As the results of the calibration for the WinHSPF, the determination coefficient (<TEX>$R^2$</TEX>) for the flow (Q, <TEX>$m^3/s$</TEX>) was 0.87 and the <TEX>$R^2$</TEX> for the SS was 0.78. As the results of the validation, the former was 0.78 and the latter was 0.67. The results seem to be acceptable. Similarly, the calibration results of the CE-QUAL-W2 showed that the RMSE for the water level was 1.08 and the RMSE for the SS was 1.11. The validation results(RMSE) of the water level was 1.86 and the SS was 1.86. Based on the daily simulation results, the water quality target (turbidity 50 NTU) was not exceeded for 2009~2011, as results of maximum turbidity in '09, '10, and '11 were 3.1, 2.5, 5.6 NTU, respectively. The maximum turbidity in the years with the maximum, the minimum, and the average of yearly precipitation (1982~2011) were 15.5, 7.8, and 9.0, respectively, and therefore the water quality target was satisfied. It was discharged high turbidity at Inbuk, Gaa, Naerin, Gwidun, Woogak, Jeongja watershed resulting of the maximum turbidity by sub-basins in 3years(2009~2011). The results indicated that the water quality target for the nonpoint source pollution management should be changed and management area should be adjusted and reduced.

Building an Integrated Governance Model and Finding Management Measures for Nonpoint Source Pollution in Watershed Management of Korea

This study intended to develop an integrated governance model and find measures to manage nonpoint source (NPS) pollutions in watershed management. To reach this goal, this study has analyzed NPS pollution management policies in Korea and has employed statistical methods such as expert Delphi survey, analysis of variance, and factor analysis. As a result, this study has found that the favored basic organization form was a private-public cooperative council. The necessary governance-based NPS pollution management measures determined through this study are as follows: to build collaboration mechanisms including those related to motivation provision, trust building, capacity building, and making optimal regulations; to employ financial resources based on principles such as ‘polluter-pays’, ‘recipient-pays’, and ‘general-tax-source’; and to develop several programs, including system improvement, pilot and management projects, and publicity.

Comparison of CANWET and HSPF for water budget and water quality modeling in rural Ontario

This study comparatively evaluates the Hydrological Simulation Program-FORTRAN (HSPF) model and the Canadian ArcView Nutrient and Water Evaluation Tool (CANWET) for non-point source pollution (NPS) management in rural Ontario watersheds. Both models were calibrated, validated, and applied to a 52 km2 headwater rural watershed known as the Canagagigue Creek near Elmira in the Grand River basin, Ontario, Canada. A comparison of the simulated and observed values for stream flow, surface runoff, subsurface runoff, evapotranspiration, and sediment yield showed that (Better Assessment Science Integrating Point and Nonpoint Sources) BASINS/HSPF and CANWET models have similar capabilities to simulate various hydrological processes at the watershed scale. The seasonal stream flow comparison between observed and simulated values from HSPF and CANWET showed Nash-Sutcliffe efficiency (Nash-E) coefficients of 0.80 and 0.72, respectively. The monthly comparison between the simulated and observed stream flow yielded Nash-E coefficients of 0.88 and 0.94 for HSPF and CANWET, respectively. Overall, both models predicted the components of the annual, seasonal, and monthly water budget accurately. There was a considerable difference in the monthly simulated sediment yield by both models. This difference is consistent with the surface runoff variation predicted by both models. Both models predicted sediment yield with early winter and spring storms which is typical for southern Ontario.

Simulation-optimization model for non-point source pollution management in watersheds: Application of cooperative game theory

A new cooperative watershed management methodology is designed for developing an equitable and efficient Best Management Practice cost allocation among landowners in a watershed. The approach intends to control the total sediment yield in the watershed, considering landowners’ conflicting interests. Wet detention ponds, are considered as the only available options to the landowners. The quality of the storm water is evaluated by the Total Suspended Solid loading from the watersheds. The proposed methodology combines a watershed simulation model, named Soil Water Accounting Tool (SWAT), with an Ant Colony Optimization (ACO) module and the cooperative game theory approach. Integration of SWAT and ACO modules provide the best set of designs for any constraints on target sediment removal set forth by non-cooperative and cooperative behaviors of the stakeholders to participate in the coalition to minimize the total cost of management practice. Nash Bargaining Theory is used to investigate how the maximum saving on cost of the participating players in a coalition can be fairly allocated. The proposed method is illustrated by a hypothetical example. The results demonstrate the applicability of the methodology. For the hypothetical case example, the proposed methodology with grand coalition leads to approximately 48 percent cost saving.

Classic Optimization Techniques Applied to Stormwater and Nonpoint Source Pollution Management at the Watershed Scale

AbstractLinear and dynamic programming formulations are introduced for optimizing the placement of distributed best management practices (BMPs) at the watershed scale. The results of linear programming optimization of infiltration-based stormwater management BMPs are compared with the results of genetic algorithm (GA)optimization using a nonlinear distributed model. Additionally, linear and dynamic programming optimization of sediment-trapping BMPs are compared with GA optimization using a nonlinear distributed model. The results indicate that the solution to stormwater peak-flow reduction is influenced primarily by distributed-flow arrival time, and a linear programming analog to a nonlinear optimization model can efficiently reproduce much of the same solution structure. Linear and dynamic programming solutions to the storm sediment-management problem indicate natural sediment trapping is an important consideration, and a solution to the sediment-management-optimization problem can be efficiently found ...