Land subsidence due to groundwater drawdown in Shanghai

Shanghai is located on the deltaic deposit of the Yangtze River, as illustrated in Fig. 1. Fig. 2 shows the main geological strata. The total thickness of the Quaternary deposit is about 300 m (Shanghai Geology Office, 1976, 1979). Excessive pumping of the groundwater caused compression of the Quaternary deposit, and subsidence in Shanghai. Although several countermeasures, including recharge of the groundwater, have been adopted to mitigate the rate of subsidence, up to the present the recorded cumulative subsidence has been 2–3 m in the central area of Shanghai. This subsidence has caused a lot of...