Land subsidence caused by groundwater exploitation in Suzhou City, China

摘要: Suzhou City, located at the lower reaches of Yangtze River in southeastern Jiangsu Province, is one few cities China which suffer from severe ground settlement. A research project was carried out to investigate this problem. Geological and hydrogeological studies show that there a multi-layered aquifer system with three distinct, soft mud layers marine lagoonal origins. An examination historical records groundwater extraction, water levels, settlement shows subsidence associated continuously increasing extraction deep, confined aquifer. It believed consolidation layers, especially third layer thick close main pumped aquifer, contributes three-dimensional finite difference numerical model representing developed study response extraction. By calibrating both measured level settlement, parameters were estimated. The outputs fit reasonably well observed results, indicates can reproduce dynamic processes flow soil consolidation. hydraulic conductivity near center has been reduced by over 30% last 14 years. gradual deterioration may have significant adverse effect on sustainable resource deep since recharge shallow aquifers through only source analysis spatial distributions drawdown area maximum not necessarily due occurrence layer. simple reallocation pumping rates basis distribution could significantly reduce