The Economic Value of Trinity River Water

The Trinity River, largest tributary of the Klamath River, has its headwaters in the Trinity Alps of north-central California. After the construction of Trinity Dam in 1963, 90% of the Trinity River flow at Lewiston was moved to the Sacramento River via the Clear Creek Tunnel, a manmade conduit. Hydropower is produced at four installations along the route of Trinity River water that is diverted to the Sacramento River, and power production at three of these installations would diminish if no Trinity River water were diverted to the Sacramento River. After Trinity River water reaches the Sacramento River, it flows toward the Sacramento-San Joaquin Delta and San Francisco Bay. Trinity River water is pumped via Bureau of Reclamation canals and pumps to the northern San Joaquin Valley, where it is used for irrigated agriculture. The social cost of putting more water down the Trinity River is the sum of the value of the foregone consumer surplus from hydropower production as well as the value of the foregone irrigation water. Sharply diminished instream flows have also severely affected the size and robustness of Trinity River salmon, steelhead, shad and sturgeon runs. Survey data were used to estimate the non-market benefits of augmenting Trinity River instream flows by letting more water flow down the Trinity and moving less water to the Sacramento River. Preservation benefits for Trinity River instream flows and fish runs are $803 million per annum for the scenario that returns the most water down the Trinity River, a value that greatly exceeds the social cost estimate.     

土地利用变化和气候波动对东江流域水循环的影响

研究土地利用变化和气候波动对东江流域水资源及水循环的影响，将为东江流域国民经济的可持续性发展、水资源的有效利用和调配等提供决策依据。以SCS模型为基础，建立适用于东江流域的月水量平衡模型，并利用8个代表流域的资料进行检验，模型结构简单，模拟结果说明所建模型具有较高的模拟精度。     

开采浅层水 增雨水入渗 引河水补源 水可持续用

南皮县淡水资源严重短缺,制约工农业与经济社会的发展。春季开采浅层地下水包括微咸水和半咸水抗旱灌溉,腾出地下含水层空间；汛期增加降雨入渗,减少径流流失,防渍防涝,把时空分布不均的天然降雨转化为地下水资源；秋冬利用河道沟渠引蓄河水补源,淡化地下水质,增加地下水可采量。地上水地下水联合运用,保持水资源采补平衡。实现旱涝碱咸综合治理、水资源可持续利用与经济社会可持续发展。     

Effects of hydrologic infrastructure on flow regimes of California's Central Valley rivers: Implications for fish populations

Alteration of natural flow regimes is generally acknowledged to have negative effects on native biota; however, methods for defining ecologically appropriate flow regimes in managed river systems are only beginning to be developed. Understanding how past and present water management has affected rivers is an important part of developing such tools. In this paper, we evaluate how existing hydrologic infrastructure and management affect streamflow characteristics of rivers in the Central Valley, California and discuss those characteristics in the context of habitat requirements of native and alien fishes. We evaluated the effects of water management by comparing observed discharges with estimated discharges assuming no water management (‘full natural runoff’). Rivers in the Sacramento River drainage were characterized by reduced winter–spring discharges and augmented discharges in other months. Rivers in the San Joaquin River drainage were characterized by reduced discharges in all months but particularly in winter and spring. Two largely unaltered streams had hydrographs similar to those based on full natural runoff of the regulated rivers. The reduced discharges in the San Joaquin River drainage streams are favourable for spawning of many alien species, which is consistent with observed patterns of fish distribution and abundance in the Central Valley. However, other factors, such as water temperature, are also important to the relative success of native and alien resident fishes. As water management changes in response to climate change and societal demands, interdisciplinary programs of research and monitoring will be essential for anticipating effects on fishes and to avoid unanticipated ecological outcomes. Published in 2009 by John Wiley & Sons, Ltd.     

Drought Subsidence Prediction Model for the Western San Joaquin Valley,California

Abstract

Land subsidence due to groundwater extraction in the western San Joaquin Valley has been studied and monitoredfor almost six decades. Although its subsidence rates diminished after 1970, the problem is still of great concern during droughtperiods. Knowing how big the social impact and cost of subsidence were in the past decades, the paper proposes an innovative approach to predicting its further occurrence. Extrapolation is based on analysis of historical groundwater subsidence relationship, drought pattern, and acceptance of new explanatory mechanisms for clay inelastic compaction. Average predicted magnitudes of subsidence in the western San Joaquin Valleyfor the next five decades are in the range 4 m to 8 m.     

GIS-Based Groundwater Management Model for Western Nile Delta

The limited availability of renewable fresh water is a major constraint on future agriculture and urban development in Egypt. The main water resource that Egypt has been depending on is the River Nile. Nowadays, the role of groundwater is steadily increasing and will cover 20% of the total water supply in the coming decades especially in the reclaimed areas along the desert fringes of the Nile Delta and Valley. Abstraction from groundwater in Egypt is dynamic in nature as it grows rapidly with the expansion of irrigation activities, industrialization, and urbanization. One of these areas is the Western Nile Delta in which the groundwater is exploited in many localities. To avoid the deterioration of the aquifer system in this area, an efficient integrated and sustainable management plan for groundwater resources is needed. Efficient integrated and sustainable management of water resources relies on a comprehensive database that represents the characteristics of the aquifer system and modeling tools to achieve the impacts of decision alternatives. In this paper, a GIS-based model has been developed for the aquifer system of the Western Nile Delta. The GIS provides the utilization of analytical tools and visualization capabilities for pre-and post-processing information involved in groundwater modeling for the study area. The developed model was calibrated for steady state and transient conditions against the historical groundwater heads observed during the last 20 yr. The calibrated model was used to evaluate groundwater potentiality and to test two alternative management scenarios for conserving the aquifer system in Western Nile Delta. In the first scenario, reducing the surface water inflow while increasing the annual abstraction from groundwater by about 450 million m³ and improving the irrigation system could increase the net aquifer recharge by about 5.7% and reduce the aquifer potentiality by about 91%. Constructing a new canal as a second management scenario could increase the annual aquifer potentiality by about 23%. The GIS-based model has been proven to be an efficient tool for formulating integrated and sustainable management plan.     

陡河流域地表水与地下水转化关系

通过对陡河流域地表水-地下水水样的氢氧同位素分布特征进行分析,发现研究区河岸带第Ⅰ含水层除了受大气降水、灌溉回归水入渗补给外,还接受河水早期的渗漏补给,第Ⅱ含水层对第Ⅲ含水层有越流补给,第Ⅱ含水层同时也受大气降水和灌溉回归水的影响,而远离河岸带的第Ⅳ含水层与上覆各含水层稳定同位素组成显著不同,河岸带水库附近的第Ⅳ含水层可能受地表水库渗漏影响。河岸带地下水与地表水水力联系的变迁严格受河岸带地下水水位变化控制,如景庄子剖面的地下水埋深为5m,雨季时河水补给地下水,旱季时地下水补给河水,而靠近地下水漏斗中心的越河乡剖面地下水水位埋深达25m,其常年受地表水补给。     

乌江流域空中水资源开发利用潜力分析

针对贵州社会经济发展和乌江流域水电生产对人工增雨的服务需求,从空中水资源开发和流域气候背景的角度分析在乌江流域开展人工增雨的可行性．并结合以往增雨服务个例．评估实施乌江流域水电生产人工增雨服务的预期效益。     

A Generalized Predictive Model of Water Table Fluctuations in Anisotropic Aquifer Due to Intermittently Applied Time-Varying Recharge from Multiple Basins

Mathematical models play a key role in assessing the future behavior of a groundwater system in response to various schemes of ground water resources development such as artificial recharging and in selecting an appropriate one out of many proposed schemes for its sustainable development. This paper presents an analytical solution of groundwater flow equation for unconfined, anisotropic, 2-D rectangular aquifer under the Boussinesq approximation to predict water table fluctuations in the aquifer in response to general time-varying intermittent recharge from multiple rectangular infiltration basins of different spatial dimensions. The horizontal anisotropy incorporated in the model is such that the principal axes of the hydraulic conductivity tensor are oriented parallel to the rectangular sides of the aquifer. The time-varying recharge rate is approximated by a series of line elements of different lengths and slopes depending on the nature of variation of recharge rate. The solution is obtained by using extended finite Fourier sine transform. Application of the solution is demonstrated with the help of synthetic examples. Numerical results of the analytical solutions are verified by comparison with the results obtained from MODFLOW. Numerical results indicate significant effect of anisotropy in hydraulic conductivity on the nature of water table variation.     

济南市有效利用城市雨水回灌岩溶地下水探讨

利用雨水补给地下水已成为城市水资源管理的有效措施.文中以济南市为例探讨了雨水回灌岩溶地下水的途径.济南市具有较好的岩溶水赋存条件,通过人工回灌工程,采用点面结合的回灌方式,利用雨水补给地下水,将城区岩溶水直接补给区的水循环尽可能地恢复到一定的自然状态,最终达到供水保泉的目的.     

Simulation and Multi-Objective Management of Coastal Aquifers in Semi-Arid Regions

Groundwater is the main water resource in many semi-arid coastal regions and water demand, especially in summer months, can be very high. Groundwater withdrawal for meeting this demand often causes seawater intrusion and degradation of water quality of coastal aquifers. In order to satisfy demand, a combined management plan is proposed and is under consideration for the island of Santorini. The plan involves: (1) desalinization (if needed) of pumped water to a potable level using reverse osmosis and (2) injection into the aquifer of biologically-treated waste water. The management plan is formulated in a multi-objective, optimization framework, where simultaneous minimization of economic and environmental costs is desired, subject to a constraint so that cleaned water satisfies demand. The decision variables concern the well locations and the corresponding pumping and recharging rates. The problem is solved using a computationally efficient, multi-objective, genetic algorithm (NSGAII). The constrained multi-objective, optimization problem is transformed to an unconstrained one using a penalty function proportional to constraint violation. This extends the definition of the objective function outside the domain of feasibility. The impact of prolonged droughts on coastal aquifers is investigated by assuming various scenarios of reduced groundwater recharge. Water flow and quality in the coastal aquifer is simulated using a three-dimensional, variable density, finite difference model (SEAWAT). The method is initially applied to a test aquifer and the trade-off curves (Pareto fronts) are determinedl for each drought scenario. The trade-off curves indicate an increase on the economic and environmental cost as groundwater recharge reduces due to climate change.     

A Framework for an Agent-Based Model to Manage Water Resources Conflicts

Competition for use of water is increasing and leads to many conflicts among competing interests with complex goals and water management systems. Technical system models are essential to create performance and other decision information, but models to simulate views of the competing parties are also needed to help resolve or mitigate conflicts. Agent-based models (ABMs) offer promise to fill this role, and in this study a new approach to agent-based modeling is introduced to simulate the behavior and interactions of the parties participating in a conflict scenario, which is modeled as a game. To develop this framework, we considered water issues of California’s Sacramento-San Joaquin Delta region as an example of a long-standing situation, with emphasis on the San Joaquin watershed. However, this approach can be used in other watersheds and more complex systems. The ABM explains the interactions among the parties and how they can be encouraged to cooperate in the game to work toward a solution. The model also enables decision-makers to test management scenarios and understand the consequences of their decisions on different stakeholders and their behaviors.     

Multi-Objective Optimization of Integrated Surface and Groundwater Resources Under the Clean Development Mechanism

Acquiring sustainable water resources for water-based development of countries is the experts? concern in this field, who seek to follow the clean development mechanism (CDM) regulations and overcome water crisis through integrated water resources management (IWRM). The Great Karun River basin is one of the major basins in the Middle East. This basin, containing six of the largest reservoir dams with a cumulative power plant capacity of more than 10,500 MW generates about 93% of hydropower of Iran. The water balance of the aquifer in the study area was simulated using MODFLOW model while water resources and surface water reserves were simulated by the water evaluation and planning (WEAP) model. A separate simulation was performed with each of two models and the results of two models were coupled using a link file. The multi-objective function optimization process including the maximized supply of demands and hydropower and the minimized aquifer drawdown was completed using non-dominated sorting genetic algorithm (NSGA-II). All effective system components, such as inter-basin water transfer, integrated use of water resources, variation of irrigation network efficiencies, and the effect of water shortage were studied and analyzed under the targeted scenarios. Finally, the best scenario, which was capable to supply the future needs until time horizon of 2040 was planned for the basin considering minimization of aquifer drawdown and optimal generation of hydropower resulting in a maximum decrease in emission of greenhouse gases.

     

Sensitivity of a Groundwater Flow Model to Both Climatic Variations and Management Scenarios in a Semi-arid Region of SE Spain

Since 1980, southern Spain has registered a cycle of drought with magnitudes consistent with forecasts by the European Environment Agency on climate change for a 20 % decrease in precipitation in southern Europe due to the acceleration of global warming. The impact of this climatic event has been taken into account in drawing up water management plans for the basins affected. However, it has barely been considered in terms of the evolution of groundwater reserves or in their modelling, possibly because the effects are often masked by intensive anthropic withdrawals from regional water resources. This research uses a mathematical groundwater flow model to evaluate the reserve evolution in the Mancha Oriental aquifer system (SE Spain) due to impacts from this drought cycle. Its influence has been quantified (from 1980 to 2008) in the aquifer's storage deficit 23 Mm³/year and in the discharge volume of the Júcar River of 21 Mm³/year. Finally, three plausible scenarios are modelled with respect to 2027, the end date of the planning horizons proposed by Directive 2000/60/EC. These scenarios examine the economic repercussions on current groundwater resource management measurements. If the drought was to persist, the costs involved in the storage deficit were calculated in the range from 21.7 to 34.9 M€.     

防渗墙作用下堤防保护区地下水动态数值模拟分析Ⅱ：二元结构堤基条件下的数值模拟

 对长江重要堤防典型二元结构堤基的地下水流运动进行了数值模拟。二维模拟结果表明：被河泓切割的承压含水层动态与江水位关系密切；表层弱透水层主要通过与承压含水层之间的补给排泄而受江水位的间接影响；全封闭防渗墙会制约堤防保护区承压含水层对江水位变化的响应；承压含水层透水性越强，这种制约作用越显著；全封闭防渗墙会使堤防保护区潜水含水层动态基本上不受江水位变化的影响。三维模拟结果表明：全封闭防渗墙端部自由绕渗会使端点附近承压含水层动态受防渗墙的影响减小；承压含水层的透水性越强，绕渗影响的程度和范围越大；绕渗在潜水含水层的作用则小得多，甚至可不予考虑。     

Conjunctive Water Use Planning in an Irrigation Command Area

In the present study, an integrated soil water balance algorithm was coupled to a non-linear optimization model in order to carry out water allocation planning in complex deficit agricultural water resources systems based on an economic efficiency criterion. The LINGO 10.0, optimization package has been used to evolve at optimal allocation plan of surface and ground water for irrigation of multiple crops. The proposed model was applied for Qazvin Irrigation Command Area, a semi-arid region in Iran. Various scenarios of conjunctive use of surface and ground water along-with current and proposed cropping pattern have been explored. Some deficit irrigation practices were also investigated. The results indicate that conjunctive use practices are feasible and can be easily implemented in the study area, which would enhance the overall benefits from cropping activities. The study provides various possible operational scenarios of the branch canals of the command area in the common and dry condition, which can help managers in decision making for the optimum allocation plans of water resources within the different irrigation districts. The findings demonstrate that for deficit irrigation options, the mining allowance of ground water value of the command area is greatly reduced and ground water withdrawal may be also restricted to the recharge to maintain the river–aquifer equilibrium.     

防渗墙作用下堤防保护区地下水动态数值模拟分析Ⅲ：多元结构堤基条件下的数值模拟

 对长江重要堤防的典型多元结构堤基地下水流运动进行了数值模拟。二维模拟结果表明：未被河流切割的含水层受江水位的影响很小；未被防 渗墙截断的含水层受防渗墙的影响也很小；被河流切割的承压含水层与江水位关系密切，但布置半封闭式防渗墙后会制约堤防保护区地下水动态对江水位的响应，承压含水层渗透性越 强，其动态受江水位影响越大，修建防渗墙后受到的制约作用也越显著；潜水含水层受江水 位的影响小得多，受半封闭式防渗墙的影响也小得多。三维模拟结果说明了防渗墙端部绕渗 影响：防渗墙端部绕渗会使墙端附近承压含水层动态受防渗墙的制约作用降低；绕渗对潜水 含水层的作用很有限，一般可以忽略不计。与二元结构堤基相比，多元结构堤基中含水层受 江水位影响较小，半封闭式防渗墙对地下水动态的影响小于全封闭式防渗墙；同样的自由绕 渗条件下，半封闭式防渗墙端部绕渗影响小于全封闭式防渗墙。      

Integrated Economic-Hydrologic Assessment of Water Management Options for Regulated Wetlands Under Conditions of Climate Change: A Case Study from the Spreewald (Germany)

This paper presents an integrated economic-hydrologic approach for the assessment of water management options for wetlands. It is based on a water resources modelling framework for long-term basin planning, that is augmented to model ecosystem service provision levels of wetlands as a function of water availability and water management. The approach is applied to a case study of the Spreewald wetland that is major fen wetland in the mid-reaches of the River Spree (Germany). Different management options at the wetland and basin scale are assessed in a cost-benefit analytical framework regarding their performance under projections of future climatic conditions. The cost-benefit analysis is based on the valuation of important wetland ecosystem services: grassland fodder production, recreational boating, habitat and biodiversity conservation and regulation of greenhouse gas emissions. It is found that under future climatic conditions, regulated and drained wetlands such as the Spreewald will require an increasing amount of water to maintain the current levels of benefits derived from the wetlands ecosystem services. Additional inter-basin water transfer could compensate some of the negative effects of increased water demand. However, the assessed transfer option is not economically efficient. Water management approaches that increase the intra-annual water storage in the wetland soils by higher groundwater level regulation targets are found to generate net gains in benefits compared to the current water management without any increase of the water supply.     

An Indicator Based Assessment for Water Resources Management in Gediz River Basin,Turkey

In this study, a water resources management model that facilitates indicator-based decisions with respect to environmental, social and economic dimensions is developed for the Gediz River Basin in Turkey. The basic input of the proposed model is the quantity of surface water that is greatly allocated to irrigation purposes; therefore, supply and demand interrelations in agricultural water use constitute the main focus of the study. The model has been applied under three different hydro-meteorological scenarios that reflect baseline as well as better and worse conditions of water supply and demand, not only to reach an assessment of water budget, but also to evaluate the impacts of proposed management alternatives under different conditions. The Water Evaluation and Planning (WEAP) software is used as a simulation and evaluation tool to assess the performance of possible management alternatives, which is measured by nine proposed indicators. The results of the study have indicated that the Gediz River Basin is quite sensitive to drought conditions, and the agricultural sector is significantly affected by irrigation deficits that increase sharply in drought periods. Even if the optimistic scenario is assumed to occur, it is not possible to observe a significant improvement in the water budget; however, the negative impacts of climate change can possibly exacerbate the water crisis. The indicators also verified that, efficient water management is crucial to ensure the sustainable use of water resources with respect to environmental, social and economic dimensions.     

Drought variability and its connection with large-scale atmospheric circulations in Haihe River Basin

Drought is one of the most widespread and devastating extreme climate events when water availability is significantly below normal levels for a long period. In recent years, the Haihe River Basin has been threatened by intensified droughts. Therefore, characterization of droughts in the basin is of great importance for sustainable water resources management. In this study, two multi-scalar drought indices, the standardized precipitation evapotranspiration index(SPEI) with potential evapotranspiration calculated by the Penmane Monteith equation and the standardized precipitation index(SPI), were used to evaluate the spatiotemporal variations of drought characteristics from 1961 to 2017 in the Haihe River Basin. In addition, the large-scale atmospheric circulation patterns were used to further explore the potential links between drought trends and climatic anomalies. An increasing tendency in drought duration was detected over the Haihe River Basin with frequent drought events occurring in the period from 1997 to 2003. The results derived from both SPEI and SPI demonstrated that summer droughts were significantly intensified. The analysis of large-scale atmospheric circulation patterns indicated that the intensified summer droughts could be attributed to the positive geopotential height anomalies in Asian mid-high latitudes and the insufficient water vapor fluxes transported from the south.