Intensive groundwater development in coastal zones and small islands

By examples from around the world, we show the vulnerability of coastal aquifers, emphasising sea intrusion from intensive groundwater development. Given a continuing high demand pressure on coastal aquifers and the high risks and costs of pollution, the issue is to make coastal zone development sustainable. This requires consideration of alternate water sources and associated prediction uncertainties, e.g. due to climate change, subsurface heterogeneity and demand/demographic evolution. We outline a research methodology and an integrated tool for investigating the feasibility of an aquifer management strategy that uses desalination of brackish groundwater, coupled with control of sea intrusion via recharge of treated wastewater. Through the case study of an aquifer in the island of Rhodes, we show that this can be an economically viable, sustainable aquifer management scheme in seasonally water-stressed, semi-arid coastal zones and islands.