A daily compilation of significant news articles and comment
April 25, 2008
2. Supply -
Salt removal could help
Reuters News Service
Water projects could be thwarted by ballot measure, state memo says –
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Salt removal could help
Reuters News Service – 4/25/08
By Maggie Fox
WASHINGTON (Reuters) - It may be possible to remove salt from more water to boost the U.S. fresh water supply, but additional studies need to be done to assess the environmental effects of doing so, a panel said on Wednesday.
Most use reverse osmosis, which pushes water through a membrane to separate out most salts. But it is expensive, uses a great deal of energy and its effects on the environment are unclear, the panel of engineers and other experts found.
The Earth is covered in water, but more than 97 percent of it is seawater or brackish groundwater and cannot be drunk or used for 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 Zander, an engineering professor at
"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," she said in a statement.
Seawater reverse osmosis, which uses membranes to filter out the salt, uses about 10 times more energy than traditional treatment of surface water, according to the report.
It may be possible to make the process more energy-efficient by making the membranes more permeable, the committee said. A method called thermal desalination is another possibility.
The independent, advisory National Research Council, part of the National Academies of Science, was asked to look into the matter by the U.S. Environmental Protection Agency and the U.S. Bureau of Reclamation.
Desalination may be less environmentally harmful than many other ways to supplement water -- such as diverting freshwater from sensitive ecosystems, the report said.
But researchers should find out whether fish and other creatures get trapped in saltwater intake systems and what the effects are of disposing of the salt concentrate created by desalination, it said.
The report recommended that federal research and development on desalination be overseen by the White House Office of Science and Technology Policy and funded at current levels of about $25 million a year.
Federal research on desalination lacks an overall strategic direction, and the majority of research was left to the private sector, it said.#
http://uk.reuters.com/article/environmentNews/idUKN2429481720080424?sp=true
Water projects could be thwarted by ballot measure, state memo says
By
Proposition 98 “could seriously hamstring or thwart future water projects,” state attorney Dave Anderson wrote in a confidential memo to superiors.
The five-page opinion surfaced just as the parties dueling over competing eminent-domain measures on the June 3 ballot wait for Gov. Arnold Schwarzenegger to weigh in.
The governor has not taken a position on Proposition 98, but the review by one of his own attorneys could persuade Schwarzenegger that the measure would stand in the way of his pursuit of new reservoirs and an improved north-to-south water delivery system.
“It is clear that this report raises serious concerns,” said Aaron McLear, a spokesman for the governor.
Supporters of Proposition 98 contend that it provides exemptions to allow government to take land for public-works projects, such as reservoirs and canals.
“A farmer's livelihood is dependent on his water supply, and the Farm Bureau would not have drafted a measure that puts his future at stake. We are strong supporters of a water-bond measure that would provide new water storage,” said John Gamper, a state Farm Bureau representative testifying yesterday before a legislative panel.
Proposition 98 generally would prohibit government from seizing property from unwilling sellers and turning that land over to another private user. Water agencies, however, are alarmed by language they perceive as ambiguous that could raise legal barriers to new projects.
The argument that the initiative could block land acquisitions for water projects is not new. Supporters and opponents of Proposition 98 have released dueling legal opinions, and the uncertainty has prompted giant water districts, including the San Diego County Water Authority and Metropolitan Water District, to oppose it. #
http://www.signonsandiego.com/news/state/20080425-9999-1n25domain.html
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