FRESNO, Calif. (AP) - California's two longest rivers, the Sacramento and the San Joaquin, were named the country's most endangered waterways by an environmental advocacy group that considers them threatened by outdated water management and poor flood planning.
American Rivers, a conservation group that compiles the annual list, chose the Sacramento-San Joaquin river system because its collapse could endanger the water supply of 25 million Californians, flood the state's capital and damage the delicate freshwater delta where the two rivers twine.
"The Sacramento-San Joaquin Delta is on the verge of losing important fish species, and the communities that surround it already don't have adequate protection from their levees," said Steve Rothert, California director of the Washington-based nonprofit. "The health of the delta depends directly on maintaining the health of these two rivers that feed it."
The organization chooses its most endangered rivers from nominations made by environmental groups and bases the selections on the value of a river to people and the environment, the level of the threat and pending decisions that could affect it in the next year, Rothert said.
But Jerry Johns, deputy director at the Department of Water Resources, said the report did not give adequate consideration to statewide efforts to restore the health of the delta and its two chief tributaries.
Rivers from Pennsylvania to Alaska also made this year's list, whose top five included Georgia's Flint River, the Lower Snake River that courses through Idaho, Washington and Oregon, Mattawoman Creek in Maryland and the North Fork of the Flathead River in Montana.
The Sacramento and the San Joaquin meet in the delta, a freshwater estuary surrounded by an aging network of fragile levees. That system of flood control has harmed the rivers' floodplains, a crucial habitat for fish and other species that use that area to feed and reproduce, Rothert said.
The delta also forms the heart of the state's water-delivery system, where snowmelt from the Sierra Nevada is rerouted through canals and pumps to reach 25 million Californians and thousands of acres of crop lands.
In recent years, court-ordered restrictions on pumping water from the delta have left dozens of cities and thousands of acres of farm fields thirsty for water.
Johns said his department has been working with a host of stakeholders - including American Rivers - to develop a long-range plan that would conserve habitat in the floodplains and shore up existing infrastructure.
"What we're trying to do is flood those habitats more frequently than just during high flood events," he said. "All of these flow issues get solved if you have a separate conveyance system that can send water directly from the northern part of the state south without passing through the delta."
Gov. Arnold Schwarzenegger, Sen. Dianne Feinstein, Republican lawmakers, many farmers and water agencies have argued for years that the state must upgrade its decades-old water delivery system. They want to build new reservoirs and a canal that routes water around the economically fragile delta. Both ideas are unpopular with some environmental groups, including American Rivers, who say the canal could trap migrating salmon and other fish that swim in the Sacramento River and might not end up improving the health of the delta, home to numerous threatened native species.
One recent political compromise will help restore a now-dry 60-mile stretch of the San Joaquin River.
Last week, President Barack Obama signed a wilderness bill that implements a 2006 legal settlement to bring water and Chinook salmon back to a portion of the state's second-longest river. It provides about $390 million in federal and state funds, as well as fees from water users, over the next decade.
The lawsuit stemmed from the opening of Friant Dam in 1949, which transformed the San Joaquin Valley's main artery from a river thick with salmon into an irrigation source for more than a million acres of farm fields.
Under the 2006 settlement, the Friant Water Users Authority, which represents 21 irrigation districts that distribute river water to thousands of farms, agreed to relinquish a set portion of their traditional water supplies to help restore the fish.
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