Delineating Capture Zone of a Pumping Well in a Slanting Regional Groundwater Flow to a Stream with a Leaky Layer

In this study, analytical and semi-analytical solutions are derived to delineate capture zone of a pumping well near a stream where a leaky layer exists between the aquifer and the stream. A groundwater regional flow is considered in the aquifer and allowed to have different angles with respect to the stream axis. Three critical pumping rates are introduced. At the first pumping rate, capture zone boundary tangents the interface between the aquifer and the leaky layer; called the in-homogeneity boundary. At the second pumping rate, capture zone boundary tangents the stream boundary and if the rate is increased, a part of pumped water would be withdrawn from the stream. The third pumping rate, which may be smaller or larger than the other two, is defined as the rate at which stream water begins to enter the leaky layer; it may or may not be captured by the pumping well. Four different capture zone configurations (cases) are analyzed for different values of pumping rates, groundwater flow directions, and leaky layer’s thickness and hydraulic conductivity. The first three cases analyze hydraulic situations whereby capture zone does not reach the stream, and hence, no pumped water is withdrawn from the stream. With the lowest pumping rate in the first case, no stream water enters the leaky layer. It enters the leaky layer but not the aquifer in the second, and enters the leaky layer and the aquifer in the third case. In the fourth case, where capture zone boundary intersects the stream, the fraction of pumped stream water to total pumped water is delineated.     

Optimal Design for Pressurized Irrigation Subunits with a Minimum Cost and Maximum Area for Uniformly Sloping Fields

The optimal design for pressurized irrigation subunits is a complicated problem that not only requires a confirmation of the layout but also requires a pipe diameter combination. Using a subunit with single lateral and a subunit with paired laterals as research objects, four mathematical optimization models were established to identify the optimal microirrigation subunit design. The optimization criteria were minimizing the annual total cost (C_T) and maximizing the subunit size (A); it was assumed that all the emitters have equal discharge, and only rectangular subunits were considered in this study. No allowable pressure differences allocation between the lateral and the manifold were made in this study, considering that there are many factors that affect the distribution ratio and the overall optimization of the subunit. A genetic algorithm was used to obtain the optimal design when simultaneously considering the layout and pipe diameters of the subunit. The results indicated that the investment cost (C_a) is the most important factor, and it makes up 43–66% of the C_T, followed by the water cost (C_w), which accounts for 28–49% of the C_T. A subunit with paired laterals is superior to a subunit with single lateral in terms of both the total cost and the control area. On the whole, with the increase in the lateral diameter, both the total cost and the control area will increase. With an increase in the emitter discharge, the total cost increases, while the control area decreases. The change of slope in the lateral direction has little effect on the total cost and control area. The method proposed in this study is applicable to the simultaneous optimization of the subunit in which the layout and area are undetermined, and it may provide a new path towards subunit optimization.

     

Estimating Pumping Rates and Identifying Potential Recharge Zones for Groundwater Management in Multi-Aquifers System

Agricultural, aquaculture, industrial and domestic activities have placed enormous demands for water, which sometimes results in the over-pumping and associated continually declining groundwater levels. This in turn has led to land subsidence and soil salination. Therefore, it’s important to understand the local pumping activities or the pumping rates in order to implement appropriate water management. The distribution of pumping rates varies spatially and temporally due to the availability of surface water and seasonality. In addition, to have correct estimate of the pumping rates, both the hydrology and geology should be consider. SWAT and MODFLOW are employed and run separately to acquire certain hydrologic components such as the recharge, boundary flow and change of aquifer storage in multi-aquifers. The water balance method (WBM) is then adopted to estimate pumping rates with these components. To validate the proposed model the results of WBM and the official records are compared. Besides, in view of the serious land subsidence occurred, artificial recharge is regarded as an effective tool to alleviate and mitigate the subsidence. Nevertheless, the location of conducting artificial recharge needs to be identified first. The potential recharge zones are assessed based on the simulated recharge rates from SWAT and the spatial distribution of hydrological characteristics of the unconfined aquifer. Ultimately, an optimal recharge zone will be suggested. The proposed methodology is proved capable of estimating the pumping rates and locating the potential recharge zone.     

南水北调东线台儿庄泵站水泵装置优化选型设计

针对南水北调东线台儿庄泵站低扬程的特点，对国内目前已有的优秀水力模型进行了综合技术比较，最终选定TJ04-ZL-19水力模型；采用CFD理论和技术对初步设计阶段选用的肘形进水、直管式出水流道进行了数学模型计算和优化，并通过透明流道模型试验对理论计算结果进行了验证。最终的水泵装置模型试验结果证实了台儿庄泵站水泵装置的水力设计达到了预期的要求。     

水库灌区抽水站水泵选型设计

在抽水站设计中,需对大量的基础数据处理后才能进行工况点的计算。此文试着在水泵选型设计计算时,对水泵工况点参数进行拟定和工况点计算的程序化,从而真正地利用计算机减少设计人员的工作量。     

论安阳市区地下水位下降漏斗演变与地下水可持续利用规划

在进行地下水资源评价时,地下水的补给排泄均衡项有许多不确定因素,这大大降低了评价的精度,也影响了地下水可持续利用规划的科学性与准确性.根据不同时期实测的安阳市区地下水位数据,研究地下水位演变过程,得出地下水位下降漏斗形成的初始与现状地下水位变幅值(1965年-2005年或1980年-2005年),利用给水度μ值,可以较精确的计算这个时段的地下水超采量.安阳河冲洪积扇具有较大的含水空间,该地区已形成稳定的地下水位下降漏斗,此漏斗是建立地下水调蓄水库良好的场所.在安阳河冲洪积扇漏斗区规划实施地下水人工回灌是一条安阳市区地下水可持续利用之路.     

新城区排涝站泵房地基处理的设计与施工

针对新城区排涝站的工程地质和场地条件,采用不同的地基处理方案进行技术经济比较论证,优选出技术上可行、经济上合理并切合工程实际的地基处理方案,并针对地基处理施工过程中应特别注意的技术问题进行分析,提出可行的技术措施.实践证明,本工程采用单管法施工的高压旋喷桩基础处理方案是合适的,值得类似工程借鉴.     

Groundwater Management for Sustainable Development of Urban and Rural Areas in Extremely Arid Regions: A Case Study

In Saudi Arabia, the recharge to local and regional aquifers is mostly indirect, very limited and insignificant, especially with low annual precipitation. Most of the stored groundwater in local and regional aquifers is non-renewable fossil water. With rapid socio-economic developments and increasing population coupled with agricultural and industrial growth in the Kingdom, especially after the large increase in oil revenues after 1974, the water demands have increased drastically. By understanding the aquifer features, the country followed a planned approach based on controlling aquifer development and demand management to use its groundwater resources. The socio-economic developments in rural areas have been very pronounced. Corrective demand management measures including reduction in cultivated areas and modification in agricultural support policies in addition to the augmentation of water supplies by the reuse of treated wastewater have reduced the stress on groundwater. The establishment of a special Ministry for water and the adoption of a national water planning approach and the use of an integrated water resources management tool are expected to contribute effectively to the achievement of sustainable groundwater resources and the national interest of the country.     

炳灵水电站轴承润滑系统设计选择

炳灵水电站在国内首创将水库的泄洪溢流明渠修建在厂房顶部的布置方式.电站水轮发电机组轴承设计特点为负荷大、转速低,为低速重载轴承,因而轴承润滑系统的合理设计和布置是机组的安全稳定运行的重要保证.对当前国内大型贯流机组普遍采用的几种润滑方式进行分析,结合炳灵水电站厂房布置的特点,优化设计,选用了适合本电站的轴承润滑方式.     

山东省地下水超采区的优势条件及改善对策

在水文地质条件、水资源、经济发展、地下水管理与科研等方面,山东省浅层地下水超采区具有优势条件,可通过地下水压采、人工回灌、节水等措施,调控地下水位,改善超采区水环境。     

北方井灌区吨粮田节水灌溉体系及效益

为解决吨粮田建设中因施用化肥多而导致灌水量大、小麦倒伏减产、生产成本高的问题,经过三个不同水文年的试验、示范验证和推广,提出了高产节水灌溉体系,包括输水渠道防渗、合理灌水、保护利用土壤水、降低生物水消耗等几个方面。应用该技术体系,除可节约灌溉用水39.6％外,还可调节地温、改土肥田、抑草、节能、省肥、增产,作物全年耗水量仅740mm,水分生产率为2.31kg/m~3,吨粮成本可降低29.8％。     

晋中市地下水超采现状及控制措施

分析了晋中市榆次源涡、榆次城区、榆次南四乡、太谷西六乡、祁县北五乡、介休城区～宋古、榆社郝北～箕城地下水超采区的发展和存在的问题,提出了地下水超采区开辟新的替代水源、压缩地下水开采量、调整农业种植结构、提高农业灌溉水利用系数等控制和治理方案.     

健全体制创新机制推进水务工作改革与发展

一、水务发展现状 从1883年上海市建成第一家自来水厂到现在,我国城市水务行业已经有118年的历史。新中国成立后,政府投入巨资发展供水事业,到2000年底,累计用于城市供水设施的固定资产投资达到12100亿元,全国663个设市城市都建有供水设施,供水能力达到     

高寒地带地下水动态在线监测系统设计与应用

针对高寒地带极端恶劣的气候环境及地下水监测野外工作的现状,研制一套环境适应性强的地下水动态在线监测系统。系统主要由水位探头、远程数据传输装置及终端平台组成。采用通用的1号碱性电池作为电源,维护方便。从系统的硬件及软件2部分着手,采取多项措施来降低仪器功耗,提高稳定性,重点解决监测仪器在低温环境下的可靠性。野外试验表明系统运行状况良好,经受住了高寒气候下的低温环境的考验,实现了系统的自动化采集及远程传输,提高了工作效率。     

Designing a Hydrological Real-Time System for Surface Water and Groundwater in Denmark with Engagement of Stakeholders

Increasing attention on extreme hydrological events has created considerable demand for real-time information on surface water, groundwater and the unsaturated zone. In the present study, we describe how to convert a national water resources model (DK-model) covering the entire freshwater cycle in Denmark to real-time application. We have engaged stakeholders in the process of designing a hydrological real-time system. The participatory approach has been supported by a web-based questionnaire survey and a participatory workshop. A system prototype presented to the stakeholders simulates groundwater levels, streamflow and water content in the root zone with a lead time of 48 h. The active engagement of stakeholders has provided very valuable insights and feedbacks regarding how model and data should be combined in a real-time to best supporting water resources management.     

大中型长距离梯级有压管道供水泵站水泵系统设计关键问题总结探讨

大中型、长距离梯级有压管道供水泵站的水泵系统设计不仅需综合考虑泵站梯级设置、泵站水锤防护、梯级泵站流量平衡等系统设计的关键问题,还需解决泵站的变工况计算、水泵调节工况计算、节能运行方式等问题。就东莞市东江与水库联网工程中的主体工程-供水水源工程探讨长距离梯级有压管道供水泵站的水泵系统设计应注意的关键性技术问题。     

舟山大陆引水一期工程泵站计算机监控系统

介绍了舟山大陆引水工程的概况以及岚山、李溪渡泵站计算机监控系统的结构和运行状况,岚山泵站采用当地一体化工控机的模式,李溪渡泵站则采用专用通信管理模件的模式.通过对2个泵站计算机监控系统的对比,提出泵站计算机监控系统的设计及实施建议,为舟山大陆引水后续工程和国内其他类似工程的建设提供参考.     

Multi-Objective Optimal Design of Detention Tanks in the Urban Stormwater Drainage System: LID Implementation and Analysis

Under the influences of climate change and rapid urbanization, extreme rainfall events become more and more intensive and the urban flooding issues have been frequently faced in many cities in the world. Previous practical and scientific experiences have demonstrated that appropriate utilization of detention facilities and low impact development (LID) devices for urban region design could be important and effective ways to the flooding control and drainage service management of an urban stormwater drainage system (USDS). This paper investigates the optimal design and application of detention tank network and LID devices for achieving these multiple objectives in the USDS. The framework and method of LID-based multi-objective optimal design of detention tanks in USDS is first developed in this study, and a practical case in SA city of China is then taken for the application. The results of this study confirm the feasibility and validity of the proposed methodological framework for the LID-based multi-objective optimal design of detention tanks in the USDS. Specifically, both total investment costs and flooding risk have been greatly reduced by the optimal implementation of the detention tank and LID measures. Meanwhile, the results indicate that the LID devices may have global effect to the flooding control and the detention tanks can be locally efficient to reduce the flooding risk. Finally, the findings of this study are discussed in the paper for their practical implications to the practical design and management of USDS.     

Multi-objective Optimal Design of Detention Tanks in the Urban Stormwater Drainage System: Uncertainty and Sensitivity Analysis

Design of detention tanks becomes important to the flooding control and drainage service management of an urban stormwater drainage system (USDS). While the hydrological and hydraulic models and methods have been widely developed in the literature for the optimal design and management of USDS, there is not yet a general methodological framework that is applicable for all practical systems. This is mainly because of various complexities in practical USDS, such as different design objectives (i.e., multi-objective design) and local design criteria and policies, as well as variety of inevitable uncertainties in the system. Previous work by the authors has focused on the first two aspects, in which a viable design framework has been developed and applied for multi-objective optimal design of detention tanks in the USDS under conditions of different local design criteria; and this paper deals with the third factor, aiming to explore and extend further the optimal design methodological framework to USDS with uncertainties. A real-life USDS in China is applied for this investigation. Uncertainty analysis is firstly conducted to characterize the importance of different uncertainty factors considered in the studied system. The uncertainty analysis result is thereafter incorporated into the previously developed multi-objective optimal design framework, in which the Monte-Carlo simulation method is adopted for the stochastic process investigation. The case application and analysis indicate different influences of uncertainty factors in the system to the multi-objective design results of detention tanks (total cost and flooding risk) in the studied USDS. The results and findings of this study are also discussed in the paper for their practical implications to the design and management of USDS.     

Development and Evaluation of Hybrid Artificial Neural Network Architectures for Modeling Spatio-Temporal Groundwater Fluctuations in a Complex Aquifer System

Water Resources Management - The proper design, development, and appropriate tuning of the Hybrid Neural Network architecture, mainly for its parsimoniousity and optimal training can help...