AN IMPLICIT APPROACH TO PRICING AGRICULTURAL WATER TRANSFERS TO URBAN USES1

ABSTRACT: The increased agricultural efficiency of the American farmer has been a substantial impetus to this nation's rapid urbanization. In many western regions where total water supplies are limited, urbanization has required the transfer of heretofore agricultural water rights to the urban use. A major problem in such transfers has been the value or price of the water. A management level model of a typical urban water system was developed to optimize water supply, distribution, and wastewater treatment alternatives. The values of agricultural transfers were determined as the cost advantages of increasing allowable reuse levels of urban effluents which imply the use of a downstream right. This procedure is justified by the economic theory of alternative cost. Results for a test application to the Denver, Colorado area indicate values on the order of $1,000 per acre-foot of transferable water depending on effluent water quality restrictions and operational policies.     

EFFECTS OF INTERBASIN TRANSFERS UPON WATER MANAGEMENT ALTERNATIVES IN CENTRAL UTAH1

ABSTRACT. Most of Utah's rapid population and industrial expansion is taking place along the western base of the Wasatch Mountains, with consequent increases in water demand. As a part of Utah's “Developing a State Water Plan,” a foundation investigation of the Utah Lake drainage area, which is at the Southern end of the Wasatch Front, was completed which delineated the quantity and quality of the water resources, present water uses, and opportunities for further water conservation. To prepare water budgets, land use data was collected to delineate all areas using water in excess of normal precipitation, which includes agricultural croplands, phreatophytes, open water surfaces, industrial areas, and urban areas. The water budgets were prepared for the time base 1931-1960, but adjusted to physical conditions existing in 1960. The Initial Phase of the Bonneville Unit of the Central Utah Project is presently under construction, with costs expected to exceed 300 million dollars. The principal feature of this project is the exportation of waters from the Colorado River Basin into the Utah Lake drainage area (Great Basin). This importation provides a large number of alternatives for allocation, reallocation of present supplies, and exportation. The possible effects of the Central Utah Project for realizing some of the above alternatives is delineated. Fortunately, the features of this project allow a wide latitude for water management in Utah, thereby facilitating its corporation into a “State Water Plan.”     

MULTISOURCE/MULTIQUALITY AGRICULTURAL WATER USE DECISIONMAKING1

ABSTRACT: The importation of water into an existing irrigated agricultural area raises many questions about farm profitability and suggests many adjustment alternatives open to farmers. In particular, how will farmers respond to a new additional water source of differing cost, availability, and quality? Mathematical programming models of representative irrigated farms in Pinal County, Arizona, were developed to project agricultural adjustments to new water from the Central Arizona Project now under construction. The techniques developed have broad application to similar water resource projects involving the conjunctive use of multiple water sources of differing qualities. Regional agricultural activities are described by defining and modeling multiple representative farms which account for economies due to size and different water sources of differing price and quality. Various management schemes can be evaluated by properly selected representative farm models.     

QUANTIFYING URBAN INTENSITY IN DRAINAGE BASINS FOR ASSESSING STREAM ECOLOGICAL CONDITIONS1

ABSTRACT: Three investigations are underway, as part of the U.S. Geological Survey's National Water‐Quality Assessment (NAWQA) Program, to study the relation between varying levels of urban intensity in drainage basins and in‐stream water quality, measured by physical, chemical, and biological factors. These studies are being conducted in the vicinities of Boston (Massachusetts), Salt Lake City (Utah), and Birmingham (Alabama), areas where rapid urbanization is occurring. For each study, water quality will be sampled in approximately 30 drainage basins that represent a gradient of urban intensity. This paper focuses on the methods used to characterize and select the basins used in the studies. It presents a methodology for limiting the variability of natural landscape characteristics in the potential study drainage basins and for ranking the magnitude of human influence, or urbanization, based on land cover, infrastructure, and socioeconomic data in potential study basins. Basin characterization efforts associated with the Boston study are described for illustrative purposes.     

AN INTEGRATED APPROACH TO WATER RESOURCES DEVELOPMENT OF THE TEHRAN REGION IN IRAN1

ABSTRACT: In this paper, a system approach to water resources development in Tehran Metropolitan Area, with its complex system of water supply and demands, is discussed. Water resources in this region include water storage in the Lar, Latyan, and Karaj reservoirs, the Tehran aquifer, as well as water discharge in local rivers and in drainage channels (mainly supplied by urban runoff and wastewater). This study consists of three phases of long‐term water resources planning and management in the Tehran metropolitan area. In each phase, a different level of details among different components of the system is considered. In the first phase, optimal operating policies for Tehran reservoirs and a decision support system are developed. In the second phase, interactions between surface and ground water resources as well as surface runoffs and wastewater disposal in different subareas are investigated. The water table fluctuations as a result of implementing sewerage collection project was also simulated. In the last phase, long‐term scenarios for water resources and agricultural development in the Southern part of Tehran are defined, and the effects of each scenario on the quality and quantity of surface and ground water resources are studied.     

STORMWATER HARVESTING IN THE URBAN WATERSHEDS OF ARID ZONES1

ABSTRACT: A representative city in an arid zone, such as the Kingdom of Saudi Arabia, is instrumented to determine the quantity and quality of storm runoff with a view to investigating the possibility of using it for industrial and agricultural purposes after appropriate treatments. In an urban watershed in the City of Dhahran, Saudi Arabia, quantity and quality of storm runoff had been monitored for the past six years, and the average annual runoff that can be harvested was determined. The quality of runoff is well within the range of possible reuse schemes, most notably for restricted irrigation. Treatment schemes for the harvested water are proposed.     

MODELING COST-EFFECTIVENESS OF AGRICULTURAL NONPOINT POLLUTION ABATEMENT PROGRAMS ON TWO FLORIDA BASINS1

ABSTRACT: A model was developed to evaluate the cost-effectiveness of alternative “best management practice” (BMP) implementation schemes on two agricultural basins in Florida. The model selectively applies BMPs throughout the basin on a field by field basis, estimates the associated costs, and predicts the relative water quality improvement (reductions in nitrogen and phosphorus). The water quality model links field scale simulation (for detailed BMP evaluation) with basin delivery and attenuation functions to predict the basin-wide effects of any combination of BMPs. Fifteen BMP scenarios were evaluated to aid in prioritizing BMPs for implementation in these basins. Applying the maximum level of BMPs is estimated to cost around $1.2 million (annually), while the four most cost-effective BMPs would cost only one quarter as much, yet are projected to provide approximately 90 percent of the water quality improvement.     

CONTINUOUS SIMULATION FOR WATER QUALITY PLANNING1

ABSTRACT: This paper describes a methodology for the evaluation of water quality plans analogous to procedures used in flood control planning, where flood damage frequency curves provide the basis for determining flood control benefits. The proposed method uses continuous water quality simulation to develop long term information from which water quality frequency curves can be obtained. This frequency information allows the evaluation of the impact of proposed water quality control plans taking into consideration the variable nature of the water resource. Using treatment costs and other economic indicators of water quality, the frequency information can be used to estimate the cost-effectiveness and economic efficiency of alternative plans. The method is demonstrated in a semi-hypothetical environment; real hydrologic and climatic characteristics are assigned to a hypothetical watershed configuration. Alternative management plans are simulated and analyzed for both physical and economic impacts. The advantages of continuous simulation and its use in water quality planning are explored.     

WASTE WATER REUSE IN PHOENIX-HOW VIABLE IS IT?1

ABSTRACT: The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the Nation for waste water reuse. Overriding all of these conditions is the long-term inadequacy of the existing water supplies. The Salt River Valley has a ground water overdraft of about 700,000 acre feet per year. To help alleviate this situation, the Corps of Engineers in conjunction with the MAG 208 is looking at ways to reuse a projected 2020 waste water flow of 340,000 acre feet per year. Reuse options identified include ground water recharge, agricultural irrigation, turf irrigation, recreational lakes, fish and wildlife habitats, and industrial cooling. These look nice on paper but before they can be implemented, some hard questions have to be answered, such as: How acceptable are local treatment plants when 15 years ago there was a major push to eliminate local plants; is the Phoenix area ready for reuse in urban areas; what are people willing to pay for water; who benefits if a city goes to ground water recharge; how much agriculture will be left in the area by 2020? These and other questions must be resolved if reuse is to become a viable option in water resource planning in the Phoenix area. Summary. Large scale reuse of waste water conforms with the national goal of better resource management through recycling. The Phoenix metropolitan area has a unique combination of circumstances which makes it one of the prime areas in the nation for waste water reuse. Some of the most notable conditions are: the existence of a large and rapidly growing urban area which is in the process of planning for future waste water management systems; the existence of agricultural areas which are projected to be farmed well into the future, and the existence of constructed and planned major recreational systems such as Indian Bend Wash which can use recycled waste water; the existence of extensive depleted ground water aquifers; the need for a dependable source for the cooling of the Palo Verde Nuclear reactors; and finally, overriding all of this, the long-term inadequacy of the existing water supplies. Given this, one would expect to find total reuse within the Phoenix metropolitan area. Reuse is taking place with irrigation and nuclear power cooling to the west but there is no long term plan which looks at the Valley as a whole and considers waste water as part of the Valley's water resources. The Corps 208 plan is looking at waste water in this manner but initial analysis shows that although reuse is technically feasible there are many financial, social, institutional, and political questions still to be answered. These include: determining the value of existing diminishing water sources and what people are willing to pay for the next source of water; are people willing to identify priority uses of water for the area so that water of varying quality is put to its highest and best use; will the present institutional boundaries remain to create water-rich and water-poor areas; and will legislation be forthcoming to simplify the complex surface and ground water laws that presently exist? The Corps 208 study will not be able to answer these questions, but the goal at the moment is to identify feasible reuse systems along with decisions the public, owners, agencies, and politicians must make to select and implement them. If some sort of logical process is not developed and public awareness not increased, the chance for a long-term plan to utilize waste water as a major element in the Phoenix area water resource picture, may be missed.     

Framework and Tools for Agricultural Landscape Assessment Relating to Water Quality Protection

While many scientific studies show the influence of agricultural landscape patterns on water cycle and water quality, only a few of these have proposed scientifically based and operational methods to improve water management. Territ’eau is a framework developed to adapt agricultural landscapes to water quality protection, using components such as farmers’ fields, seminatural areas, and human infrastructures, which can act as sources, sinks, or buffers on water quality. This framework allows us to delimit active areas contributing to water quality, defined by the following three characteristics: (i) the dominant hydrological processes and their flow pathways, (ii) the characteristics of each considered pollutant, and (iii) the main landscape features. These areas are delineated by analyzing the flow connectivity from the stream to the croplands, by assessing the buffer functions of seminatural areas according to their flow pathways. Hence, this framework allows us to identify functional seminatural areas in terms of water quality and assess their limits and functions; it helps in proposing different approaches for changing agricultural landscape, acting on agricultural practices or systems, and/or conserving or rebuilding seminatural areas in controversial landscapes. Finally, it allows us to objectivize the functions of the landscape components, for adapting these components to new environmental constraints.     

重庆渝北双龙湖综合治理与工程实践

城市水景水体的修复和保持是水资源保护与可持续利用研究中的热点之一，重庆市双龙湖是典型的城市水景水体，治理前富营养化状况严重。双龙湖治理采取了综合整治的方案，包括污水截流工程、雨水截流及净化工程、湖水复氧循环工程、湖水的生态治理工程和污泥固化工程等。截断外源污染，抑制内源污染，有效的控制了水体的富营养化。经过治理，双龙湖水体水质明显提高，由治理前的劣Ⅴ类水质恢复到Ⅳ类水质，满足景观水要求。双龙湖水环境综合整治为我国，特别是三峡库区众多的城市水体的修复和保持积累经验，为城市水景水体富营养化的防治提供技术和方法上的借鉴。     

Spatiotemporal Variability in Water Sources Controls Chemical and Physical Properties of a Semi‐arid Urban River System

We conducted synoptic surveys over three seasons in one year to evaluate the variability in water sources and geochemistry of an urban river with complex water infrastructure in the state of Utah. Using stable isotopes of river water (δ¹⁸O and δ²H) within a Bayesian mixing model framework and a separate hydrologic mass balance approach, we quantified both the proportional inputs and magnitude of discharge associated with “natural” (lake, groundwater, and tributary inputs) and “engineered” (effluent and canal inflows) sources. The relative importance of these major contributors to streamflow varied both spatially and seasonally. Spatiotemporal patterns of dissolved oxygen, temperature, pH, calcium, chloride, nitrate, and orthophosphate indicated seasonal shifts in dominant sources of river water played an important role in determining water quality. We show although urban rivers are clearly influenced by novel water sources created by water infrastructure, they continue to reflect the imprint of “natural” water sources, including diffuse groundwater. Resource managers thus may need to account for the quantity of both surface waters and also historically overlooked groundwater inputs to address water quality concerns in urban rivers.     

WATER SUPPLY,TREATMENT, DISTRUBTION,AND REUSE OPTIMIZATION IN ARID URBAN AREAS1

ABSTRACT: A Management level model has been formulated in which a system analysis format is employed to answer some of the basic questions regarding urban water management strategies The model incorporates a multilevel optimization scheme to coordinate urban water supply, distribution, and wastewater management. A test of the model's utility is made in an application to the water management problems of the Denver, Colorado metropolitan area. Denver has utilized both agricultural transfers and transmountain diversions to supplement the natural stream resources of the South Platte River. Although plans are being made to increase the capacity of these sources, increasingly stringent standards on the area's effluents are enhancing the feasibility of reclaiming and recycling a portion of the wastewater. The urban model used in this study indicates the decision points at which respective strategies are introduced. However, by formulating the model from a planner's viewpoint, the most important results gained from the analysis are the costs of various institutional constraints which may restrict the decision maker's ability to implement optimal policies.     

THE ROLE OF AGRICULTURAL GROUNDWATER CONSERVATION IN ACHIEVING ZERO OVERDRAFT IN ARIZONA1

ABSTRACT: The elimination of groundwater overdraft was a key feature of the 1980 Arizona Groundwater Management Act. To achieve this goal, the Arizona Department of Water Resources identified several Active Management Areas and developed urban, industrial, and agricultural water conservation plans. This study examines the reductions in groundwater use through agricultural water conservation in the Phoenix Active Management Area (AMA). Linear programming models are developed to analyze changes in groundwater use and net returns to agriculture over a 38-year period, 1990 to 2025, for farming areas in the Phoenix AMA. Results indicate that the agricultural conservation program provides only modest groundwater savings under a wide range of scenarios. The low level of savings is partly due to the current economically efficient use of water. Other policy measures such as retiring agricultural land may be necessary if the Phoenix AMA is to meet its overdraft reduction goals; even if urban water conservation goals are met.     

张家口市中心城区饮用水安全的探讨

饮用水与人民群众的生活与健康休戚相关，因此保护饮用水水源地尤其重要。张家口市中心城区的饮用水水源地为地下水水源地，市区共有南北五个集中式供水水源地。近年来，由于农业污染、生活污染、个别企业超标排污以及上游来水不达标等原因，水源地水质下降。本文主要从5个水源地的水质、水量现状出发，探讨了影响水源地安全的因素，并提出相应的水源地保护措施：切实落实《饮用水水源地保护规划》、加强监管和立法以及提高公民环境意识。     

WATERSHEDSS: A DECISION SUPPORT SYSTEM FOR WATERSHED-SCALE NONPOINT SOURCE WATER QUALITY PROBLEMS1

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 .     

Exploring Nontraditional Participation as an Approach to Make Water Quality Trading Markets More Effective

Water quality trading (WQT) has the potential to be a low‐cost means for achieving water quality goals. WQT allows regulated wastewater treatment plants (WWTPs) facing discharge limits the flexibility to either reduce their own discharge or purchase pollution control from other WWTPs or nonpoint sources (NPSs) such as agricultural producers. Under this limited scope, programs with NPSs have been largely unsuccessful at meeting water quality goals. The decision to participate in trading depends on many factors including the pollution control costs, uncertainty in pollution control, and discharge limits. Current research that focuses on making WQT work tends to identify how to increase participation by traditional traders such as WWTPs and agricultural producers. As an alternative, but complementary approach, we consider whether augmenting WQT markets with nontraditional participants would help increase the number of trades. Determining the economic incentives for these potential participants requires the development of novel benefit functions requiring not only economic considerations but also accounting for ecological and engineering processes. Existing literature on nontraditional participants in environmental markets tends to center on air quality and only increasing citizen participation as buyers. Here, we consider the issues for broadening participation (both buyers and sellers) in WQT and outline a multidisciplinary approach to begin evaluating feasibility.     

THE DEVELOPMENT OF A COMBINED WATER QUALITY INDEX1

ABSTRACT: Use-oriented benefits and treatment costs analysis has been incorporated into a water quality index to show an economically optimized concentration for the treatment of the pollutants and the resulting water quality. This combined water quality index can be used in decisionmaking at the federal and local government levels. Five major pollutants, i.e., coliforms, nitrogen, phosphorus, suspended solids, and detergent, have been considered for the municipal waste water. With each higher level of improvement the treatment costs increase accordingly and the benefits associated with the reuse of this treated waste water will increase too but not for the nutrient removal in agricultural use. The optimal concentration is determined when the marginal costs equal the marginal benefits. The combined water quality index is the combination of the maximum net benefits and the water quality index of the optimized residual concentrations. This water quality index is zero dollars for the Tucson region in this study. The possible reclaimed use of municipal waste water is for agricultural irrigation and recreational lakes for the Tucson region.     

WATER QUALITY MANAGEMENT OF SKUDAI RIVER1

ABSTRACT: Urban runoff as well as industrial and agricultural discharges have seriously affected the water quality of the Skudai River, Malaysia. A water quality model is developed for simulating BOD and oxygen relationship. The simulated values agree relatively well with survey data taken during low flow conditions. Survey and simulated values show that a pollution abatement program is needed to prevent further deterioration of the river from organic discharges. A systems approach, involving complete analysis of water quality models and environmental control procedures, considering various water use patterns, water quality criteria, and waste input, is essential for solution.