Desalination: Status and Federal Issues

摘要

In the United States, desalination is increasingly investigated as an option for meeting municipal water demands, particularly for coastal communities that can desalinate seawater or estuarine water, interior communities above brackish groundwater aquifers, and communities with contaminated water supplies. Adoption of desalination, however, remains constrained by financial, environmental, regulatory, and other factors. At issue is what role Congress establishes for the federal government in desalination research and development, and in construction and operational costs of desalination demonstration projects and full-scale facilities. Desalination processes generally treat seawater or brackish water to produce a stream of freshwater, and a separate, saltier stream of water that has to be disposed (often called waste concentrate). Desalination's attractions are that it can create a new source of freshwater from otherwise unusable waters, and that this source may be more dependable than freshwater sources that rely on annual or multi-year precipitation, runoff, and recharge rates. Many states (most notably Florida, California, and Texas) and cities are actively researching and investigating the feasibility of large-scale desalination plants for municipal water supplies.