US scientists say desalination could help meet America's future water needs, but more research is needed to reduce costs and environmental impact.
In a report, the National Research Council (NRC) said improving technology was making it more realistic to consider desalination of water.
Some 97 per cent of the water on Earth - seawater and brackish groundwater - is too salty for drinking or irrigation.
"Uncertainties about desalination's environmental impacts are currently a significant barrier to its wider use, and research on these effects - and ways to lessen them - should be the top priority," said Amy K Zander, chair of the committee that wrote the report and a professor at Clarkson University.
"Finding ways to lower costs should also be an objective. A coordinated research effort dedicated to these goals could make desalination a more practical option for some communities facing water shortages," Zander said in a statement.
There is currently no overall coordination of federal research on desalination, and the analysis recommended the government work be coordinated by the White House Office of Science and Technology Policy.
Most desalination research has been funded by private business, the report notes.
Environmental concerns include threats to fish and other aquatic animals from water intakes, high energy use in the salt-removal process and disposal of the salty sludge left over from the process.
The study was sponsored by the US Bureau of Reclamation and US Environmental Protection Agency.
The National Research Council is an arm of the National Academy of Sciences, an independent organisation chartered by Congress to advise the government on scientific matters.
