宁波市地下水应急供水模式探讨——以大嵩江流域为例

Discussion of emergency groundwater supply mode in Ningbo City:case of Dasong River Basin

应急水源地作为突发性事件导致供水困难情况下解决城市水源危机而采用的一种非常规的临时供水水源,是城市用水安全与社会稳定发展的重要保障。以宁波市具代表性的大嵩江流域为例,从合理利用与有效增加地下淡水资源角度出发,提出了“沟谷型”、“封存型”淡水水源地与地下淡水库建设相结合的区域地下水应急供水模式,并对大嵩江流域塘溪沟谷潜水、咸祥平原Ⅱ承压封存淡水体应急水源地与Ⅰ承压含水层地下淡水库建设条件进行了分析。结果表明:塘溪沟谷潜水与咸祥平原Ⅱ承压封存淡水体应急开采潜力较大,具有应急水源地建设可行性;咸祥平原Ⅰ承压含水层地下淡水库建库条件好,可通过区域水资源人工调蓄有效增加地下淡水资源量。多类型地下水水源地相结合的应急供水模式可充分挖掘和合理利用区域地下淡水资源潜力,为宁波市应急供水保障体系建设提供参考。

The emergency water source,as an unconventional temporary water source to solve the urban water source crisis when the water supply is difficult due to emergencies,is an important guarantee for urban water safety and social stable development.Taking the representative Dasong River Basin in Ningbo City as an example,and from the perspective of rational utilization and effective increase of underground freshwater resources,we proposed a regional emergency groundwater supply mode that combined“valleys”freshwater sources,“sealed”freshwater sources,and underground freshwater reservoirs.Then,the construction conditions of phreatic water emergency water source of Tangxi valley,2^(nd) confined aquifer's sealed freshwater emergency water source of Xianxiang plain,and 1^(st) confined aquifer freshwater reservoir of Xianxiang plain were analyzed.The results indicate that phreatic water of Tangxi valley and the 2^(nd) confined aquifer's sealed freshwater of Xianxiang plain have great potential of emergency exploitation as emergency water source.The 1^(st) confined aquifer of Xianxiang Plain has good conditions of underground freshwater reservoir construction,and can effectively increase underground freshwater resources by regulation of regional water resources.The emergency water supply mode that combines multiple types of groundwater sources can sufficiently excavate and reasonably use the potential of regional underground freshwater resources,and provide references for the emergency water supply security system of Ningbo City.