REUTERS/Robert Durrell/Pool

The San Joaquin River flows from the Sierra Nevada to the Central Valley, where much of its water is diverted to aqueducts.

UPDATE: The House has passed the bill, with a vote of 246-175. It now goes to the Senate.

Meandering through the halls of Capitol Hill is a bill that would dramatically change California’s water picture. Sponsored by Tulare County Congressman Devin Nunes, the sweeping proposal would pipe more water to farms, and challenge the largest river restoration project in U.S. history.

Environmentalists and farmers tangoed for 18 years in federal court over the fate of the San Joaquin River, finally agreeing to restore water to some 60 miles of dry riverbed, and bring back the salmon that died off when the river was dammed just above Fresno.

“Most people associate the San Joaquin as a dry toxic river,” says Chris Acree, director of Revive the River, a Fresno-based non-profit. “Now that this water is back in that river, it allows us to identify ourselves with this river as a living river. This restoration program really is the broadest collaboration between agencies, landowners, stakeholders, and water users, where everybody has a voice.”

But Congressmen Devin Nunes says many Central Valley farmers have been left out of water decisions that put fish before farmers. His bill would not only reverse plans to restore salmon to this river, it would relax pumping restrictions in the Delta designed to protect other endangered fish.

“This is a case where the environmental radicals have overstepped their bounds, broken deal after deal after deal to where they’ve left entire communities without water,” he says. “And that simply was never the intent of the endangered species act, and never the intent of of Congress to begin with. This is just common sense.”

Some 70 water districts and a number of farm groups are supporting the Nunes bill. But legislators from Delta communities say the plan is a water grab designed to overturn 150 years of California water rights to benefit a small group of powerful Central Valley farmers.

Even if the bill passes the house, its supporters face an upstream fight to win in the Senate. And the Obama administration has threatened a veto, saying the Nunes bill would unravel decades of work to solve some of California’s most complex water challenges.

Read More:

• Follow the status of H.R. 1873

• Legislative Summary of The Sacramento-San Joaquin Valley Water Reliability Act (PDF), by Congressman Devin Nunes
• Statement from the White House (PDF), opposing the bill