GRANTS PASS, Ore. (AP) -- A federal report says removing four hydroelectric dams on the Klamath River in Oregon and California and restoring ecosystems will produce a big increase in salmon harvests and boost farm revenues.
The 400-page report was produced by federal scientists to help the secretary of Interior evaluate whether it is in the public interest to go ahead with the $1 billion project, which is considered the biggest dam removal in U.S. history if it goes through as planned in 2020.
"In the long run, all the anadramous fish (salmon, steelhead, and lamprey) benefit from dam removal, according to our analysis," Dennis Lynch, program manager for the U.S. Geological Survey, who oversaw the report, said Monday.
The report notes that wild salmon runs have dropped more than 90 percent from the dams, overfishing, poor water quality, disease and habitat loss. It said there was a moderate to high probability that removing the dams and restoring the environment would improve water quality, fish habitat, and water quality, and reduce fish disease a toxic algae blooms. The project would also improve the ability of fish to cope with global warming, by opening up more access to cold water.
Though there would be a short-term loss of less than 10 percent of chinook and coho salmon due to the release of sediments built up behind the dams, their numbers would grow by 80 percent over the long term due to opening up more than 420 miles of habitat blocked by the dams since 1922, the report said.
Overall, the benefits far outweigh the costs, by as much as 47.6 to one, the report found.
The report estimates that dam removal would increase commercial fishing harvests of Klamath chinook 43 percent over the next 50 years, for a value of $134.5 million. Sport and tribal harvests would also climb. More irrigation for farms during drought years under terms of the Klamath Basin Restoration Agreement would produce economic benefits one out of every 10 years, for increased value of $30 million over the next 50 years. More water for wildlife refuges that depend on leftover irrigation water would produce more waterfowl, generating a $4.3 million boost from hunting.
There would be a $35 million loss in recreation revenues from the loss of the reservoirs behind the dams over the next 50 years.
Dam removal and ecosystem restoration have been endorsed by the states of Oregon and California, the dam owners and 42 groups representing Indian tribes, salmon fishermen, farmers and conservation groups. But the project has been stalled in Congress, where the House and Senate last year did not take up legislation that would authorize the Secretary of Interior Ken Salazar to proceed and appropriate up to $800 million for ecosystem restoration.
"We're pleased that this step in the evaluation process is complete and are eager to see increased focus on the settlement agreements from Congress this year," said PacifiCorp spokesman Bob Gravely.
The estimated $291 million cost of removing the dams would be paid mostly from a surcharge on electric rates that has already been approved. The state of California has yet to come up with a way to pay its share.
The report represents the compilation of 50 separate reports on issues including biology, hydrology and economics. It does not differ significantly from a draft produced last year, which went through extensive peer review. It was posted to a government website late Friday, and will be delivered to Salazar this week, Lynch said.
Straddling the Oregon-California border, the Klamath Basin regularly has trouble meeting the water demands of farms on the federal irrigation project at the top of the basin, endangered sucker fish in the irrigation system's main reservoir, and threatened coho salmon in the Klamath River. Chinook salmon returns to the Klamath are important for sport, commercial and tribal salmon harvests.
The federal government shut off water to most of the farms in 2001 to protect the salmon. After a summer of bitter protests and political battles, the Bush administration restored irrigation in 2002, only to see tens of thousands of adult salmon die of gill rot diseases that spread rapidly between fish crowded into low pools of warm water.
The two events led many farmers, tribes, conservation groups and salmon fishermen to overcome their longstanding differences and agree to a water-sharing plan that is linked to removing four small hydroelectric dams owned by PacifiCorp that serve 70,000 customers in southern Oregon and Northern California.
On the Web: Klamath Dam Removal report: http://1.usa.gov/VN0uqR