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1.
ABSTRACT. Theoretical and practical results are summarized for a study to determine optimal water resource allocation in a proposed water conservancy district. The area of this district, which covers several river basins, contains a large number of existing and proposed facilities such as reservoirs and diversions. The operation of all of these facilities was to be determined along with the sizing of the proposed facilities in order to optimize given objective functions. Related efforts in optimal river basin utilization were surveyed, and linear programming was selected as an expedient optimization technique. The problem is formulated by identifying time stages which together constitute a repetitive cycle such as a year. With these stages, it is possible to associate operational and capacity variables with network components, which are branches and nodes. Objective functions are assembled for the component variables. Constraint equations are written in terms of the variables to reflect network nodal continuity, capacity restrictions, and adjudications such as water rights. A numerical example is considered in which the existing and proposed facilities are aggregated to produce a small, tractable number of facilities. This paper examines the example results and suggests future improvements for models of this type.  相似文献   

2.
    
ABSTRACT: Once referred to as America's “best landscaped sewer,” the Connecticut has undergone a dramatic transformation in the last three decades. During this time, a number of public agencies and private organizations have worked diligently to implement policies and measures aimed at improving the river's quality. Ample data collected over the years indicate that the actual water quality conditions of the Connecticut River, as measured by empirical parameters, have improved. However, prior to this study, no data existed regarding the public's perceptions of these changes. This paper will address this issue by presenting the results of a multiyear survey designed to assess the public's perceptions regarding the Connecticut's current quality, and its suitability in supporting various recreational activities. The results suggest that the majority of individuals perceive the Connecticut's water quality to be high enough to support a wide range of recreational activities including those involving physical contact with the water. Additionally, this research concludes that the vast majority of individuals who have recreated on the river for 20 years or more do perceive a significant improvement in the river's overall quality. Thus, it appears that policies and actions taken to improve the Connecticut's quality have been successful in the public's eye.  相似文献   

3.
ABSTRACT: Accurate valuation of recreational lakes and rivers in contingent valuation (CV) studies requires that the definition of the environmental good being sold meets the requirements of correspondence, proximity, and familiarity. The concept of ‘water quality’ normally used fails to meet these requirements. This paper offers a broader concept of “lake/river quality” - a collection of physical, ecological, and aesthetic characteristics that create the opportunity for recreation, scenic enjoyment, and fish and wildlife propagation - that better describes the characteristics that recreationists value in lakes and rivers. The concept therefore better meets CV requirements and should be the basis for defining environmental improvements and declines to be hypothetically sold in CV surveys.  相似文献   

4.
    
High anthropogenic pressure on coastal ecosystems, competition for natural resources and climate change are major challenges to the sustainable management of coastal areas. Two cases of resource use conflicts in coastal urban areas in the south and west of Sweden analysed here illustrate these challenges. The social practices of using and integrating knowledge and joint learning in conflict resolution show that dominant actors and their knowledge practices have a strong influence on conflict resolution and its outcomes. Improved conflict resolution requires more efforts to achieve knowledge integration and joint learning of stakeholders in open, dialogue-based strategies in all phases of the resolution process.  相似文献   

5.
ABSTRACT: Texas river authorities are a type of large, regional water district that must be financially self-sufficient. An institutional and historical study of Texas river authorities reveals the broad power of these organizations and their influence in water management. River authorities now control 25 percent of surface water deliveries in Texas. Over two-thirds of authority water was developed by river authorities; nearly one-third was purchased from private or public ventures. While river authority activities have been effective where these services are marketable, the provision of public good services is limited. Increased visibility of these organizations is paralleled by challenges to their traditional autonomy.  相似文献   

6.
虚拟水以其形象的表达和丰富的内涵,成为2000年以后全球水科学研究领域的热点,被广泛认为是深入研究水资源管理的重要概念,也是衡量人类对水资源系统真实占有量的有效工具。文章系统介绍了虚拟水的基本概念,并对其目前在我国水资源管理领域的应用做了系统性的阐述和探讨。  相似文献   

7.
    
ABSTRACT: A significant portion of all pollutants entering surface waters (streams, lakes, estuaries, and wetlands) derives from non-point source (NPS) pollution and, in particular, agricultural activities. The first step in restoring a water resource is to focus on the primary water quality problem in the watershed. The most appropriate NPS control measures, which include best management practices (BMPs) and landscape features, such as wetlands and riparian areas, can then be selected and positioned to minimize or mitigate the identified pollutant(s). A computer-based decision sup. port and educational software system, WATERSHEDSS (WATER, Soil, and Hydro-Environmental Decision Support System), has been developed to aid managers in defining their water quality problems and selecting appropriate NPS control measures. The three primary objectives of WATERSHEDSS are (1) to transfer water quality and land treatment information to watershed managers in order to assist them with appropriate land management/land treatment decisions; (2) to assess NPS pollution in a watershed based on user-supplied information and decisions; and (3) to evaluate, through geographical information systems-assisted modeling, the water quality effects of alternative land treatment scenarios. WATERSHEDSS is available on the World Wide Web (Web) at http://h2osparc.wq.ncsu.edu .  相似文献   

8.
9.
通过分析加拿大阿尔伯塔省农用水资源的利用现状,从旱灾和水事件引发公众对水资源管理重要性认识的视角导入,从政策法规制定、水市场建立、节水技术应用和公众参与等层面归纳了阿尔伯塔省农用水资源管理的主要经验和做法,藉以对我国干旱半干旱地区的水资源管理提供借鉴和参考.  相似文献   

10.
滏阳河衡水市区段严重的黑臭污染给两岸的居民造成了工作、生活舒适性的威胁, 严重破坏了周围的环境景观.本研究采用意愿调查价值评估法,以滏阳河衡水市区段沿岸人口较稠密的21个居民区为调查对象,运用调查问卷调查居民对滏阳河环境改善的支付意愿.研究结果表明:衡水市居民为改善滏阳河水体黑臭的平均支付意愿是 66.82元/(户·年),全市总支付意愿是633.8万元/年,说明全市人民对滏阳河的治理需求还是非常迫切的.  相似文献   

11.
/ The management of industrial reservoirs for hydroelectric energy can cause severe impacts to surrounding communities. This study examines the generation of dust along the northern foreshore zones of Williston Reservoir in northern British Columbia. The dust is generated in the spring when the reservoir levels are low and impacts a relocated First Nations' village (Tsay Keh) at the north end of the reservoir. Data were gathered to provide an overview of the physical conditions that contribute to the dust problem, including a social survey, soil analysis, and vegetation inventory. The study provides a scoping method to assess a large-scale and complex problem with respect to dust management along a large reservoir. Methods for dust control include short- and long-term solutions that integrate the use of native vegetation along the foreshore zones of the reservoir.  相似文献   

12.
ABSTRACT: There is a lamentable absence of comprehensive planning in the current cursade to improve water quality. A serious shortcoming is the lack of evaluation of the effects of waste water treatment upon environmental quality. At some point in time the public may ask what they have obtained for their money. The nature of pollution in a river basin demands a coordinated attack against it. Engineering and economic criteria suggest that a properly empowered river basin authority would be the logical organization to plan and operate a water quality management system. Several forms of such authorities have operated effectively and efficiently for many years in the United States and other industrialized countries. Examples of successful river basin authorities and their advantages and methods of operation are discussed.  相似文献   

13.
ABSTRACT The American Indian occupies a unique place in the federal system of government There are indications that this relationship will continue and that Indian reservations are at the threshold of economic development. As this occurs, the nature and extent of Indian water rights becomes more important to Indian and non-Indian alike. The determination of these rights is a matter of more than judicial decisions. To a large degree the determination of these rights will rest in the non-judicial arena and will be influenced by the perceptions of those rights held by Indians and water allocation officials, both state and federal. If the perceptions of these political actors are not congruent, then political conflict will occur as the rights become more important. To depend solely upon the judicial system to resolve these conflicts entails risks and costs to both Indians and to allocating officials. Indians are taking seriously the federal policy of Indian self-determination, and water allocation officials run decided risks in failure to realize this. An alternative suggested is to include Indians as consulting parties when decisions are being made that affect Indian interests.  相似文献   

14.
    
A wastewater model was applied to the Potomac River watershed to provide (i) a means to identify streams with a high likelihood of carrying elevated effluent-derived contaminants and (ii) risk assessments to aquatic life and drinking water. The model linked effluent discharges along stream networks, accumulated wastewater, and predicted contaminant loads of municipal wastewater constituents while accounting for instream dilution and attenuation. Simulations using 2016 data suggested that nearly 30% (8281 km) of streams were wastewater impacted. Low- to medium-order streams had the largest range of accumulated wastewater (ACCWW%) values. ACCWW% exceeded a 1% threshold at >39% of drinking-water intakes (varied by temporal condition). Risk assessments of municipal wastewater-contaminant mixtures indicated that 22% (1479 km) of streams impacted by municipal wastewater (5.5% of all reaches modeled) may pose high risk to aquatic organisms under mean-annual conditions, with fish more susceptible to chronic-exposure effects relative to other taxa. Risk varied temporally and by stream order, with the greatest risk occurring in the summer in small streams. These findings suggest that wastewater may be an important factor contributing to environmental degradation in the Potomac River watershed.  相似文献   

15.
    
We assess the potential financial benefits of rooftop rainwater harvesting (RWH) in Mexico City from the perspective of property owners and entrepreneurs. A bottom‐up approach was followed by evaluating RWH at individual buildings and aggregating the results to a borough/city level. We consider sector‐specific water demands, potable and nonpotable uses, and user‐specific water tariffs. We find that RWH is economically most beneficial for nondomestic users rather than for small domestic users, who are often the target of RWH interventions. Based on a net present value analysis, a potable RWH system is not favored for most domestic users under the current subsidized municipal water tariff structure. Our analysis only considers capital and maintenance expenses, and not other benefits related to increased access to water and reliability, or social benefits from a switch to a RWH system. If the initial capital expense for RWH is partly financed by transferring the water subsidy to an entrepreneur, then RWH becomes financially attractive for a wide range of domestic users. To improve water access in Mexico City, RWH is attractive in the most marginalized boroughs where water use is currently lower and precipitation is higher. For domestic users relying on trucked water, RWH can have great financial benefits. Our approach provides quantitative data with high spatial specificity, highlighting the places and types of users that would benefit most from RWH.  相似文献   

16.
    
Abstract: Two CVM surveys were administered to 211 urban households and 188 rural farmer‐irrigators in the Comarapa watershed in Bolivia, South America, to estimate stakeholder willingness to pay (WTP) for a proposed upper watershed restoration program. Mean monthly household WTP to improve drinking water was $1.95 (65% of current charges), while mean annual WTP among farmer‐irrigators to improve irrigation water was $17 per hectare (34% of current costs). Aggregated to the entire population of households and farmer‐irrigators total WTP is $77,400 per year, which is 77% of the minimum cost to implement a watershed restoration program.  相似文献   

17.
Abstract: Total Maximum Daily Load (TMDL) implementation generates benefits and costs from water quality improvements, which are rarely quantified. This analysis examines a TMDL written to address bacteria and aquatic‐life‐use impairments on Abrams and Opequon Creeks in Virginia. Benefits were estimated using a contingent valuation survey of local residents. Costs were based on the number and type of best management practices (BMPs) necessary to achieve TMDL pollution reduction goals. BMPs were quantified using watershed‐scale water quality simulation models (Generalized Watershed Loading Function and Hydrological Simulation Program‐FORTRAN). Based on our projections, the costs to achieve TMDL induced pollution reduction goals outweigh the estimated benefits. Benefit‐cost ratios ranged between 0.1 and 0.3.  相似文献   

18.
Interregional conflicts over the allocation and transfer of water supplies have occurred with increasing frequency in the contemporary United States. This paper presents the results of a case study of citizen opposition to a proposal to transfer water supplies within Oklahoma. Residents of the area adjacent to Lake Tenkiller in eastern Oklahoma were surveyed concerning their reactions to a proposal of the City of Tulsa to transfer large volumes of water from the reservoir to the city. Results of the survey indicated that a community based concern for preserving local water levels transcended individual self-interests in maintaining Tenkiller's water levels. The results support the recently developed concept of “turf politics,” which suggests that regional and community based considerations tend to dominate interregional locational conflict resolution.  相似文献   

19.
以生态工业园区为研究背景,对生态工业园区的水资源管理模式进行了系统的研究,并借用计算机构件理论和生态工业学理论重点分析了生态工业园区水资源管理模式的设计思路,从而实现了水资源管理模式生态意义上的水链及水网的建设。其核心成果是要建立一个面向循环经济的生态工业园区水资源管理模式。  相似文献   

20.
为探讨香港水质管理的措施及效果,本文对香港吐露港地区5条河流10个监测点1985—2014年的地表水质数据进行分析,观察水体整治管理前后污染物浓度的变化。结果表明:10个监测点的氨氮、BOD_5、COD和TP的浓度均逐年下降,上下游共同努力,使各项污染物得到很大程度的削减,并且治理前后的浓度存在明显统计学差异(p0.05),且治理之后各项污染物年均浓度趋于平稳,达到标准以内。由此可以看出,香港地区水质管理效果的显著与其所实施的《水污染管制条例》、禽畜饲养禁制区设立与吐露港及牛尾海污水收集整体计划密不可分。随着国务院颁布的《水污染防治行动计划》的施行,香港吐露港地区治理的措施可为我国现阶段黑臭水体整治工作所借鉴。  相似文献   

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