GIS based aquifer vulnerability assessment in Hangzhou-Jiaxing-Huzhou plain, China

Abstract

Hangzhou-Jiaxing-Huzhou plain is among the regions which faces the shortage of water due to its increasing population, industrialization, agriculture and domestic use; hence there is high dependence on ground water. In China, the exploitation of aquifers has been historically undertaken without proper concern for environmental impacts or even the concept of sustainable yield. In order to maintain basin aquifer as a source of water for the area, it is necessary to find out whether certain locations in this ground water basin are susceptible to receive and transmit pollution, this is why the main objective of this research is to find out the ground water vulnerable zones using Geographical Information System (GIS) model in Hangzhou-Jiaxing-Huzhou plain. GIS was used to create ground water vulnerability map by overlaying hydro-geological data. The input of the model was provided by the following seven data layers: Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone and hydraulic Conductivity. This study showed that Hangzhou-Jiaxing-Huzhou area is grouped into three categories: Highvulnerable zone with 27.4% of the total area, moderate vulnerable zone which occupy the greatpart of that area 60.5% and low vulnerable zone with 12.1%. This research suggests first theprioritization of high vulnerable areas in order to prevent further pollution to already pollutedareas; next the frequent monitoring of vulnerable zones to monitor the changing level ofpollutants; and finally suggests that this model can be an effective tool for local authorities whoare responsible for managing ground water resources in that area.

Keywords: Hangzhou-Jiaxing-Huzhou plain, Ground water vulnerability, GIS, DRASTIC model, shallow aquifer