地下水资源战略储备评价与应急利用——以武汉市为例

当城市遭受突发事件或极端气候时,单一的地表水资源存在明显的供水安全隐患,严重影响城市正常运行。在地下水资源相对丰富的地方,可建立地下水战略储备应对突发事件出现的水资源短缺问题,但目前缺乏地下水资源战略储备选址的评价依据。为此,从地下水储备区供水能力、应急利用影响、社会经济发展、环境灾害影响等方面,采用层次分析法建立了地下水资源战略储备选址适宜性评价指标体系。同时,以长江流域中下游典型城市——武汉市为例,考虑供水规模和含水层富水性,对圈定的5个靶区开展了地下水资源战略储备区选址评价,其结果均为适宜性较强。在此基础上,采用Feflow从开采井布置方案和应急时间等角度,对地下水资源战略储备区应急利用方案进行评价,结果表明:应急时间较短时,抽水井布井方案对地下水动态影响较小;随应急时间增加,抽水方案对地下水动态影响越显著,但影响程度随抽水井间距增加而减小。研究成果可为长江流域中下游地下水战略储备布局及应急利用提供参考。

Evaluation Index System and Emergency Use of Groundwater Strategic Reserve:A Case Study on the City of Wuhan

Emergencies or extreme climate events would pose potential risks to the water supply security in cities with only surface water source. In cities with abundant groundwater resource,groundwater strategic reserve can be built to cope with the problem of water shortage arising from emergencies. Nevertheless,systematic basis for evaluating the site selection of strategic reserve area is still in lack at present. In view of this,an evaluation index system of the suitability of site selection for strategic reserve of groundwater resource was established by using analytic hierarchy process. The index system involves groundwater supply capacity,impact of emergency use,socio-economic development,and environmental disaster impact. With the city of Wuhan,a typical city in the middle and lower reaches of the Yangtze River Basin,as a case study,the suitability of five target sites of groundwater strategic reserve was evaluated in consideration of the scale of water supply and the water-richness of aquifers,and the results showed strong suitability of target sites. On this basis,Feflow was employed to evaluate the emergency utilization scheme from the perspective of layout of mining wells and emergency time. The results manifest that with the increase of emergency time,the influence of pumping scheme on groundwater dynamic became more significant,but such influence attenuated with the increase of pumping well spacing. The research finding could provide reference for the site selection of groundwater strategic reserve in the Yangtze River Basin.