Modeling the influences of land reclamation on groundwater systems: A case study in Shekou peninsula, Shenzhen, China

Land has been reclaimed along the coastal areas in many parts of the world to meet the growing demand for houses and other land use. Over 15 km2 of land has been reclaimed around the Shekou peninsula, Shenzhen, China. Land reclamation may have significant influences on groundwater systems but this problem has not been adequately studied. Using FEFLOW (Diersch, 2005), a three-dimensional finite element groundwater model, the response of the groundwater system on the impact of land reclamation in the Shekou peninsula from 1983 to 2007 was simulated. The model was calibrated against observed groundwater levels in three observation wells. The results showed that, after reclamation, there was a regional increase of groundwater level in the study area. The groundwater divide between western and eastern coastlines moved during different reclamation stages. The results also showed that, submarine groundwater discharge along the coastlines was increased due to the increase of recharge in the newly reclaimed land. The model predicts change of groundwater level between 2007 and 2025, which demonstrates that the response of the aquifer system to land reclamation is a long lasting process. There will be a further increase in groundwater level and it may take about 10 years for the systems to reach a new equilibrium. It is suggested that the changes of the groundwater flow system due to large-scale land reclamation should be modeled before reclamation to investigate possible engineering and environmental consequences.