The quality and availability of freshwater resources are becoming increasingly stressed as coastal human populations rise throughout the globe. In existing and emerging coastal cities where surface water pollution increases and supply declines (often triggered by changing climate), governments may turn to groundwater as an alternative source; those that have done so already may not be utilizing this resource using best management practices. In arid climates, countries are already relying on desalination of coastal seawater for the majority of their freshwater needs. For example, the acute lack of natural water resources and the wealth of Kuwait have created a unique water sector where about 90% of the potable water production comes from seawater desalination. Though this unusual situation has been maintained for decades, and probably will continue into the foreseeable future, it has resulted in serious drawbacks. At a per capita demand of 493 L/day and a $3/cubic meter production cost, the ever-increasing economic burden of satisfying the water demand is bound to slowdown the pace of development.
Thus, although desalination is an effective way to generate a fresh water supply for a coastal community, the process can be expensive and this expense can interfere with the ready availability of potable water to the local population.
Thus there exists a need to develop desalination processes that are more cost effective.
In many instances where desalination is used, the processes are not as efficient as possible and in particular fail to harvest coastal groundwater as the supply source. This can result in coastal groundwater being underutilized and lost to the ocean via submarine groundwater discharge (SGD), or trapped in offshore aquifers. Once it exits the aquifer, the freshwater component of SGD is lost to the sea. Recovery of this resource for desalination (or direct use) purposes has been under consideration for a number of years and has been tested through a number of feasibility studies. The Municipal Water District of Orange County (MWDOC) has installed a slant well into the beach-face near Dana Pt., Calif. (http://www.mwdoc.com/). There, brackish to saline groundwater will be extracted and desalinated at a soon to be constructed test facility. A French company has successfully mined offshore SGD (mainly as freshwater springs) in a number of countries around the world (http://www.nympheawater.com/).