The bill — co-authored by Boxer — authorizes hundreds of water projects across the country, including new infrastructure to fix lead issues in Flint, Mich., and and millions of dollars for projects connected to the Los Angeles River, Salton Sea and Lake Tahoe.
Earlier in the week, House Majority Leader
The bill passed the House by a vote of 360-61 (including 36 of 53 California members) on Thursday before representatives left town for the year.
Described as drought relief, the proposal focuses on environmental restrictions that have at times limited water flow from the delta to its dry southern neighbors.
Salmon fishing and conservation groups and members of Congress from Northern California condemned the water proposal as a last-minute attack on the environment and the fishing industry. But San Joaquin Valley growers and urban water agencies urged its passage.
Boxer and environmentalists' issue is that the measure would allow officials at state and federal water management agencies to exceed the environmental pumping limits set under the Endangered Species Act to capture more water, especially during storms. Those limits have been a pet peeve of water contractors, including the Westlands Water District and the Metropolitan Water District of Southern California, which complained of water supplies "lost to the sea" during last winter's heavy rains.
"We got pretty good storms last winter and the... regulators were so risk adverse they said you can't pump hardly any of it," said Tim Quinn, executive director of the Association of California Water Agencies, which represents public water districts across the state.
Federal biologists have said certain levels of water flowing through the delta are vital for native fish, which have suffered devastating losses during the prolonged drought, and help maintain the quality of the delta's freshwater supplies.
Feinstein said Friday that she came on board with the new policy after tracking daily water levels "and seeing where, if it were possible, we could have saved water without impacting fish."
The bill states more than 30 times that the new policy does not supersede existing environmental laws, and Feinstein disagrees with Boxer's insistence that it weakens the Endangered Species Act.
Saying the change in policy is akin to attacking the landmark law, Boxer spent the last few days trying to persuade colleagues to kill the entire bill, which includes more than two dozen water projects in California alone.
She spoke passionately on it for about 90 minutes Friday, slamming her fist against the lectern repeatedly.
"It isn't easy. It breaks my heart," she said, urging her colleagues to either strip out the language or kill the bill.
The retiring senator had vowed to do everything in her power to stop the legislation, but the overwhelming House vote convinced her it was a lost cause.
"I've made my point and I've spoken enough. It's a very uphill battle," Boxer said. "I'm a realist; I've been here a long time."
When she spoke on the Senate floor hours later, Feinstein laid out why she supports the plan, calling it "the result of three years of painstaking public work."
"California is home... to more than 40 million people, and our major water infrastructure hasn't been significantly changed in the past 50 years when we had 16 million," Feinstein said. "We must modernize the system, both infrastructure and operational flexibility, or I fear we risk eventually becoming a desert state."
The final language includes chunks of a bill Feinstein introduced in February, which was considered twice by the Senate Energy and Natural Resources Committee but never made it to the full Senate. Feinstein has called it one of the most difficult bills she has ever worked on.
"We have addressed, to the best of our ability and on and on and on, concerns raised by environmentalists, water districts, federal and state agencies and the [agriculture] sector," she said. "I believe that these provisions will place California on a long-term path to drought resiliency."
The White House hasn't issued a veto threat for the bill. Press Secretary Josh Earnest said earlier in the week there was some leeriness about the new California language, but that the president would look at the entire bill in deciding whether to sign it.
Still, that doesn't mean the water will immediately begin flowing. Boxer and several legal experts said Friday they expect the legislation to quickly draw legal challenges over whether the pumping provisions amount to an override of the environmental law.
Supporters may say it doesn't change the Endangered Species Act, but "I think that's probably not exactly true when they're this prescriptive. It probably is going to override" the act's rules, said Holly Doremus, a professor of Environmental Regulation at the UC Berkeley School of Law.
Doremus said other parts of the new policy were contradictory and could spawn a barrage of lawsuits.
"It is awfully messy. There will be a lot of litigation," she predicted.
Boxer said she's counting on it, though she's not sure what, if any, role she will play.
"I hope they take this to court, Day One," Boxer said. "Of course it's going to end up in court."
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Read more about the 55 members of California's delegation at latimes.com/politics