GroMoPo Metadata for Aynalem Well Field model

Improved understanding of linkages of hydrogeological systems with human interactions is required for sustainable development of groundwater resources in arid and semiarid regions. In this paper, an integrated approach coupling geographical information system (GIS) and a finite-difference method-based numerical model was used to carry out groundwater flow modeling of the Aynalem well field aquifer system in Ethiopia to determine impacts of external hydraulic stresses on the groundwater regime and to investigate the long-term effects of current pumping practices for municipal water supply to the city of Mekelle, Ethiopia. It incorporates stream-aquifer interaction, water budgeting, and long-term groundwater level prediction. Results show good agreement between simulated and observed hydraulic heads with a correlation coefficient of 0.97. The well yield potential would decrease because of the alarming rate (1.9 m= year) of decline in groundwater level. An approximately 38-m decline in groundwater level is expected by the end of year 2022, and thus no additional wells are recommended for groundwater sustainability. Results reveal the need of regulation on groundwater draft, determination of optimized pumping rates, and groundwater recharge measures for the sustainability of groundwater resources. The sensitivity analysis reveals that the recharge is more sensitive compared to hydraulic conductivity and streambed conductance.(C) 2017 American Society of Civil Engineers.

干旱半干旱地区地下水资源的可持续开发，亟需深化对水文地质系统与人类活动相互作用关联机制的认知。本文采用地理信息系统（Geographic Information System，GIS）与基于有限差分法的数值模型耦合的集成方法，对埃塞俄比亚艾纳勒姆抽水井区含水层系统开展地下水流模拟，以探究外部水力应力对地下水动态的影响，以及当前埃塞俄比亚默克莱市市政供水抽水方案的长期效应。该模拟涵盖河流水-含水层相互作用、水量均衡计算与长期地下水位预测等环节。模拟结果与实测水头数据吻合度优异，相关系数达0.97。受地下水位以每年1.9米的惊人速率下降影响，抽水井产水能力将出现衰减。预计至2022年末，地下水位将累计下降约38米，因此为保障地下水资源可持续性，不宜新增抽水井。研究结果表明，为实现地下水资源可持续开发，亟需开展地下水开采管控、优化抽水方案确定以及地下水补给措施研究。敏感性分析结果显示，相较于水力传导系数与河床导水系数，补给量对模型参数的敏感性更高。©2017美国土木工程师协会。