南通滨海新区地下水应急水源地风险预测

Risk prediction of groundwater emergency water sources in Nantong Binhai new area

地下水过量开采一直是江苏沿海地区地面沉降产生与发展的主要影响因素,地下水应急水源地的建设对提升城市供水保障能力、维护社会和谐、稳定具有重要现实和战略意义。为合理利用与保护沿海地区地下水资源,有效地将地下水开采产生的地质灾害影响程度降到最小,以南通滨海新区为例,将地下水资源仅作为应急备用水源并提出两种地下水应急供水方案,利用GMS软件建立了地下水流-地面沉降耦合数值模型,开展两种应急供水方案实施后地质风险的预测。结果表明:在满足南通滨海新区应急供水需求的条件下,两种方案实施后,仅会在应急开采井所在的区域产生地下水位降落漏斗和地面沉降的现象,同时在应急供水结束后,地下水位快速回升,地面沉降出现回弹的现象,总体产生的地质环境风险很小,两种地下水应急供水方案均具有可行性。

Groundwater excessive exploitation has always been a main factor on the occurrence and development of land subsidence in Jiangsu coastal areas.The planning and construction of groundwater emergency water source has important practical and strategic significance for improving urban water supply security capacity and maintaining social harmony and stability.This paper took Binhai New Area in Nantong City as an example to realize rational exploitation and protection of groundwater resources and to effectively minimize the impact of the generated geological disasters.Two emergency water supply schemes were designed with the basis that groundwater resources should be used only as emergency water supply,and the geological risk prediction after the implementation of two emergency water supply schemes was carried out by establishing a coupling model of groundwater flow-land subsidence with GMS software.The results showed that under the condition of meeting the emergency water supply demand of Nantong Binhai New Area,the groundwater level falling funnel and ground subsidence only occur in the area where the emergency production well is located,after the implementation of the two schemes.In addition,after the emergency water supply ends,the underground water level rises rapidly,ground subsidence appears rebound phenomenon,the overall geological environment risk is very small,and both kinds of emergency water supply plans of groundwater are feasible.