Best Management Practices Optimization at Watershed Scale: Incorporating Spatial Topology among Fields

Best management practices (BMPs) are widely used to reduce nonpoint source pollutions. In order to obtain cost-effective BMPs configurations, optimization methods are introduced. Recent studies show that knowledge on BMP placement can be used to improve existing algorithms for BMPs optimization. However, some important knowledge has not been fully utilized yet, one of which is about the spatial topology among fields and BMPs interactions. In this paper, a new method for BMPs optimization was proposed, which incorporated knowledge of BMPs interactions into a multi-objective genetic algorithm (i.e., ε-NSGAII) based on spatial topology among fields. Then this method was applied to the BMPs optimization in a small agricultural watershed in Southern Manitoba of Canada, and the performance was compared with those of conventional method. In order to make a comprehensive comparison, experiments were conducted under different population sizes (i.e., 60, 100, and 200) and different numbers of fields (i.e., 29, 52, and 79). The results showed that the proposed method was superior to conventional method on the aspect of greater sediment reductions (2% - 17%) at the same cost, and the Pareto curves obtained by the proposed method were more complete. This study demonstrated that incorporating spatial topology among fields into BMPs optimization can lead to better results and this finding could provide valuable references to similar studies.     

Optimizing Structural Best Management Practices Using SWAT and Genetic Algorithm to Improve Water Quality Goals

A genetic algorithm (GA), an evolutionary optimization technique, is coupled with a semi-distributed hydrologic model, Soil and Water Assessment Tool (SWAT) to find an optimum combination of structural Best Management Practices (BMPs) that meets the treatment goals at a watershed scale. The structural BMPs considered in the study are detention ponds, parallel terraces, filter strips, grassed waterways, and grade stabilization structures which are all applicable in agricultural watersheds. The decision variables in the optimization model are the type, size, and location of BMPs which minimize the construction cost and simultaneously reduce sediment and nutrients to target levels at the watershed outlet. The model is demonstrated on the Silver Creek, a sub-watershed of the Lower Kaskaskia watershed in Illinois. The model is used to compare three different sediment and nutrient reduction cases (i.e. 20%, 40%, and, 60%) at the watershed outlet.     

Selecting Agricultural Best Management Practices for Water Conservation and Quality Improvements Using Atanassov’s Intuitionistic Fuzzy Sets

Improper agricultural practices can affect ground water through leaching, surface water through runoff, algae infestations, deforestation, and air quality through burning operations and ammonia emissions. These effects may be mitigated through the institution of best management practices. The utility of best management practices (BMPs) is recognized and being actively promoted by agricultural agencies; however, identifying a set of mandatory BMPs is inappropriate given variations between climactic, demographic and geographic regions as well as differences in farming practices. In this study, a multi-criteria decision making model based on Attanassov’s Intuitionistic Fuzzy Set (A-IFS) theory is introduced and its utility to rank agricultural best management practices is illustrated using a case-study from South Texas. Implementation of the A-IFS MCDM method to the South Texas region resulted in “irrigation scheduling” being ranked as the most preferred alternative, while “brush control/management” was the least preferred. The A-IFS MCDM approach was particularly suitable for prioritizing and ranking agricultural best management practices because decision makers often tend to have both likes and dislikes with regards to specific BMPs and for a given evaluation attribute. Not only does the A-IFS MCDM method provide a single composite score to rank the BMP alternatives, but the output of the A-IFS MCDM method also includes upper and lower bounds that help identify the uncertainties in the decision making process.     

Technical Communication: Usage of Storm Water Best Management Practices in Southern California

Severe economic recessionary times beginning in 1990 in southern California and the concurrent introduction of National Pollution Discharge Elimination System permit requirements provided a backdrop to evaluate Best Management Practices (BMP) cost effectiveness. This study analyzes municipal Best Management Practices for municipalities in five southern California counties; Los Angeles, Orange, Riverside, San Bernardino, and San Diego. The hypothesis of this study is that due to the severe economic recessionary times, the BMPs implemented with the greatest frequency (by cities in the five counties studied) are the most cost-beneficial for cities to implement. Each city located in the five counties studied is identified as a coastal, valley, or mountain city. The number of cities that have implemented each BMP are categorized to determine which BMPs are most frequently implemented on a regional basis, and are therefore the most cost-beneficial.     

Methodology for Allocation of Best Management Practices Integrated with the Urban Landscape

Water Resources Management - Best management practices (BMP) seek to mimic the pre-development hydrological behavior by increasing infiltration and reducing runoff. However, its use worldwide is...     

Optimal Water Quality Management Considering Spatial and Temporal Variations in a Tidal River

There is an increasing need to establish wastewater treatment facilities for improving water quality of heavily polluted rivers in rapidly urbanizing areas. Optimization models are widely used to determine the pollutant removal levels at different pollution sources, with the aim of minimizing the wastewater treatment cost and satisfying certain water quality criteria. Water quality is usually evaluated in a prescribed space or time point. Thus it cannot reflect the overall status of a tidal river that has significant spatio-temporal variations. In this paper, new spatio-temporal water quality criteria, which consider the water quality violation against specified water quality standards during the whole simulation period of time for the entire river simulated, are proposed and then applied to optimization of a wastewater treatment system in Shenzhen, China. The results indicate that the optimization based on the proposed criteria facilitates an improved performance of wastewater treatment systems in terms of water quality along the whole river during a long time period, instead of just in a prescribed space or time point. Furthermore, use of the new criteria derives a better Pareto front of cost and water quality in terms of convergence and coverage compared with the conventional criteria and thus they are recommended as the water quality criteria to measure spatial and temporal variation in a tidal river for wastewater treatment system planning.     

Spatial Optimization Models for Water Supply Allocation

Climate change is likely to result in increased aridity, lower runoff, and declining water supplies for the cities of the Southwestern United States, including Phoenix. The situation in Phoenix is particularly complicated by the large number of water providers, each with its own supply portfolio, demand conditions, and conservation strategies. This paper details spatial optimization models to support water supply allocation between service provider districts, where some districts experience deficits and others experience surpluses in certain years. The approach seeks to reconcile and integrate projections derived from a complex simulation model taking into account current and future climate conditions. The formulated and applied models are designed to help better understand the expected increasingly complex interactions of providers under conditions of climate change. Preliminary results show cooperative agreements would reduce spot shortages that would occur even without climate change. In addition, they would substantially reduce deficits if climate change were to moderately reduce river flows in Phoenix’s major source regions, but have little effect under the most pessimistic scenarios because there are few surpluses available for re-allocation.     

Evaluation of the Best Management Practices at the Watershed Scale to Attenuate Peak Streamflow Under Climate Change Scenarios

The objectives of this study are (1) to develop a calibrated and validated model for streamflow using the Soil and Water Assessment Tool (SWAT) for the Lower Pearl River Watershed (LPRW) located in southern Mississippi, and (2) to assess the performance of parallel terraces, grassed waterways, and detention pond BMPs at attenuating peakflows at the watershed-scale under changes in precipitation, temperature, and CO₂ concentrations. The model was calibrated and validated for streamflow at 4 USGS gauge stations at the daily scale from 1994 to 2003 using the Sequential Uncertainty Fitting (SUFI-2) optimization algorithm in SWAT-CUP. The model demonstrated good to very good performance (R²?=?0.49 to 0.90 and NSE?=?0.49 to 0.84) between the observed and simulated daily streamflows at all 4 USGS gauge stations. This study found that grassed waterways had the highest peak flow reduction (?8.4 %), followed by detention ponds (?6.0 %), and then parallel terraces (?3.1 %) during the baseline climate scenario. Combining the different BMPs yielded greater reduction in average peak flow compared to implementing each BMP individually in both the current and changing climate scenarios. This study also found that the effectiveness of BMPs to reduce peakflows decreases significantly when increased rainfall or increased CO₂ concentrations are introduced in the watershed model. When increasing temperatures or decreasing rainfall is incorporated in the model, the peakflow reductions caused by BMPs generally does not change significantly.     

Water Quality Management in California

ABSTRACT

California is a land of contrasts. Within its boundaries are the highest and lowest elevations in the continental United States. The climate varies from subtropical to alpine and regional rainfall ranges from less than 50mm to more than 2,500mm annually. Water is a scarce and precious resources in California.

The basic approach used in Californias water quality control program is first to identify beneficial uses of the waters and then to develop water quality standards that are sufficient to protect the waters for those uses. The water quality control plan (basic plan) provides the technical basis for determining waste discharge requirements, taking enforcement actions, and evaluating clean water grant proposals. The paper discusses the background and philosophy of water pollution control practices in California with a specific example in the Sacramento River Basin.     

糯扎渡水电工程建设的质量管理实践

糯扎渡水电工程的质量管理借鉴了国内外其他工程的先进经验,同时又具有鲜明的"糯扎渡特色"。通过不断创新质量管理理念、建立健全工程质量管理体系、加强体系运行的有效性,基本做到了制度建设无缺漏、管理过程无漏洞、监督实施无缺为。采用事前控制及早预防、事中控制及时纠正、事后控制总结经验,互相衔接、严格把关,保证了糯扎渡水电工程质量在控、受控。     

如何加强水利工程施工质量管理

该文就如何加强水利工程质量管理,确保工程质量,分析了影响水利工程施工质量的主要因素,提出了提高水利工程质量的措施.     

如何加强水利工程施工质量管理

该文就如何加强水利工程质量管理，确保工程质量，分析了影响水利工程施工质量的主要因素，提出了提高水利工程质量的措施。     

Accounting of Transboundary Ecocompensation Standards Based on Water Quantity Allocation and Water Quality Control Targets

In China, under the premise that the water quantity allocation and water quality control targets for transboundary rivers have been determined, ecocompensation between upstream and downstream areas is urgently needed in management practice when targets cannot be met in the transboundary section. A dynamic accounting method for ecocompensation standards needs to be established at the scientific level. However, the accounting method of the existing ecocompensation standards is not sufficient. The purpose of this study is to propose a transboundary compensation standard accounting method based on water quantity allocation and water quality control targets and to establish ecocompensation standard accounting formulas for the Shaying River watershed. The accounting process is as follows: the water quantity compensation standard in different water quantity scenarios is calculated from the perspective of the water resource value. By using the comprehensive pollution index method, the water quality compensation standard is calculated in different water quality scenarios, and the ecocompensation standard calculation formulas for watersheds are determined. As an application, 27 types of ecocompensation standard formulas for the Shaying River watershed were determined for 3 hydrological frequencies (50%, 75% and 95%), 3 water quantity scenarios (equal-quantity, excess-quantity and reduced-quantity discharging) and 3 water quality levels (equal-quality, inferior-quality and better-quality discharging). The results not only provide a compensation standard for the Shaying River but also provide a reference for the calculation of ecocompensation standards for other transboundary rivers in China with definite water quantity and water quality management objectives.

     

末级渠系水价管理体制改革实践

陕西省是全国缺水的省份之一.水资源总量442亿m3,人均、亩均水资源量为1240m3和950m3,分别为全国平均水平的54%和42%,其中主要粮食产地关中的人均、亩均占有水资源量为380m3和250m3,相当于全国平均水平的1/8和1/6.农业灌溉是用水大户,在目前农民人均纯收入较低的情况下,不断加强水价管理,改革末级渠系水价管理体制,不仅对减轻农民浇地不合理负担、保持农村社会稳定,保障灌区正常运行有着重要意义,而且对水资源合理利用有重要的促进作用.     

建立一体化水质监测管理体系服务珠江流域水资源管理

随着珠江流域人口的增长和工业化进程的加速,水资源相对越来越匮乏,而流域环境污染又使水质性缺水现象雪上加霜,水资源短缺和水污染加重已直接制约着经济的发展,影响人民身体健康和社会安定。水的流域特性决定了水资源的管理和保护必须以流域为单元进行,作为流域水资源管理的基     

水利工程质量管理存在的问题及对策分析

当前国内水利工程质量总体水平虽有较大提高,但质量问题仍然存在,质量事故时有发生。如何采取有效措施,提高我国水利工程质量依然是当前水利工程的一个重要课题。该文分析了水利工程质量存在的问题及其产生的原因,提出了大力整顿规范水利建筑市场秩序、落实项目法人责任制、提高设计质量、保证施工质量、提高监理工作水平、做好政府质量监督工作、及时组织竣工验收、加强质量管理等方面的对策、措施与建议。     

Assessment of Water Quality Management in Turkey

Abstract

There has been a noticeable increase in the amount of pollution in water resources in Turkey in recent years. Negative environmental developments, such as industrialization, increasing urbanization, improper pesticide and fertilizer applications in agricultural lands, and the drainage of domestic and industrial wastewater into water resources without any waste treatment applications, cause rapid pollution of both surface and groundwater resources. Therefore, it is necessary to allocate more attention to water resources monitoring and evaluation studies to prevent the pollution of water resources, and to reclaim these resources.     

加强水资源管理 优化水资源配置

对泰兴市水资源管理体制的现状进行了分析。指出地表水和地下水要统一管理运用 ,须改变由于体制问题造成的地表水与地下水、城镇水资源与城市水资源的分割管理状况 ;重视地下水开发利用管理 ,研究农田灌溉用水定额。     

水利工程建设质量管理体系优化

水利工程承载防洪减灾、农业灌溉、河流治理等诸多公益性社会功能,在国民经济和社会发展中占有重要地位。未来十年,我国将有4万亿元资金投入到水利工程建设。长期以来,由于体制和机制原因导致水利工程建设质量状况堪忧。将系统理论中的协同学原理应用于水利工程建设质量管理,在现行质量监督体系和建设主体质量保证体系组成的二元结构体系基础上,引入社会质量信用评价体系,通过对建设主体质量保证子体系的完善治理、政府质量监督子体系的重构以及社会质量信用评价子体系的构建,建立了由这三个子体系构成的三元结构的协同质量管理体系,从而有效保证水利工程建设质量。