Desalination, the process of converting seawater to freshwater, dates back to 4 BC when Greek sailors evaporated seawater to create drinking water. Desalination imitates our earth’s hydrologic cycle--the sun supplies energy to evaporate water from various sources (ocean, lakes, streams, etc.) and produces water vapor, which re-condenses to form dew or rain when it cools down.

Since desalination is a relatively controversial issue, this website will be taking case studies from developed plants in California, Israel and Australia to show different perspectives on desalination in the following areas: social, environmental, and political/economic. Desalination has many potential benefits, including cheaper freshwater and the ability for cities to have public water sources. However, there are many negatives as well. Desalination technology developed in the last century from multistage flash distillation to reverse osmosis. Multistage flash distillation (MFD) heats salt water under a vacuum to evaporate pure water, which is eventually condensed and captured. Reverse osmosis (RO) forces water through plastic membrane that reject salts. Both appear to seamlessly provide a reliable source of fresh water from the ocean. Unfortunately, both methods generate a concentrated brine, are extremely energy-intensive, and expensive. Desalination appears to relieve our water-scarcity problems, however, long-term research about MFD and RO desalination is non-existent and raises concerns about the financial and environmental consequences associated with the large, energy-intensive facilities.  

Because of the lack of long-term research, it is difficult to assess what the actual impacts of desalination plants will be. Furthermore, sustainable desalination is entering the industry, although there is even less literature on that. Once the technology is more available, this option may make desalination appear more viable than current models. Regardless of how much of the impacts we understand, desalination has gained popularity due to the potential for it be a solution to water scarcity issues. The notion of turning salt water, which our earth is very abundant in, into freshwater seems feasible and almost ridiculous not to attempt, especially when increasing sources of freshwater are needed with increasing population size, decreasing levels of natural freshwater sources, and growing drought-stricken regions. With many positives and negatives to desalination, a larger issue at hand becomes apparent. While desalination can increase the water available for communities and whole cities, it points to the larger issue of water conservation. Desalination can offer a temporary fix for water scarcity, but with an increasing global population, it would be more beneficial to look towards how we can reduce our use of water, and make our intake and treatment process more sustainable.