数值模拟法在地下水水源地保护区划分中的应用

摘要

Groundwater is the key part of Beijing water supply system. Even after the South-to-North Water Diversion to Beijing, groundwater will also play a vital role and never fade away from the stage of history. PRC Water Pollution Prevention and Control Law expressly states that China has established the drinking water source reserve system. The establishment of groundwater source conservation area is the most important measure to protect groundwater from human activities to ensure the safety of water quality. As a case study of typical groundwater source area, we establish hydrogeological conceptual model of groundwater system, which is based on relevant hydrogeological exploration and long-term dynamic observation, water resource exploitation of the status quo, planning and pollution source survey data. The hydraulic capture zone of the water source is calculated by the particle tracking technique. We determine the range of the water source conservation area in consideration of the factors such as the terrain, the ground object and the potential risk of the water source. The study shows that the numerical simulation method can describe the hydrogeological conditions and groundwater aquifer structure actually. The result can provide reasonable and effective protection basis for the groundwater management department.%地下水资源是北京供水系统的支柱，设立地下水水源地保护区，是保护水源地最大可能免受人类活动影响、保证水质安全的重要措施。论文以北京市某典型水源地为例，在收集相关水文地质勘查、长期动态观测、水源地开采现状、规划及周边污染源调查等成果资料的基础上，建立了地下水系统水文地质概念模型，模拟出地下水流场。通过质点追踪技术，计算水源地水力捕获带范围。综合考虑水源地周边地形、地物和潜在风险污染源等因素，确定了水源地保护区的范围。结果表明，数值模拟法能客观详细地刻画实际地下水含水层的结构与水文地质条件，划分结果可靠、准确，能为地下水管理部门提供有效合理的保护依据。