WASHINGTON -- The House on Thursday gave final approval to a $33.5 billion energy and water bill, a snap compared to a future Sacramento-San Joaquin Delta package some lawmakers now envision.

The appropriations bill easily approved Thursday funds projects throughout the Central Valley, including Delta levee studies and regional flood control. Its final passage was never in doubt, as it's one of a dozen bills needed to run the federal government in fiscal 2010.

But even as lawmakers were approving the energy and water bill, which includes $40 million for restoration of the Delta and San Francisco Bay, they were starting to anticipate a potential new bill focused strictly on the vulnerable Bay-Delta region. If it flies, the prospective Delta legislation could literally reshape California.

"The Delta estuary has enormous national significance," Democratic Sen. Dianne Feinstein reiterated Thursday, and "it is seriously at risk."

Feinstein first revealed her intentions for a comprehensive Delta bill in a brief interview Wednesday with the San Francisco Chronicle. The seemingly offhanded revelation made following a heated public hearing caught many by surprise. Well-connected lobbyists and water district officials contacted Thursday, speaking on condition of anonymity, admitted being caught off-guard by the prospect of a big Delta bill.

Behind the scenes, though, California lawmakers including Democratic Sen. Barbara Boxer and Reps. Jim Costa, D-Fresno, and Dennis Cardoza, D-Merced, have quietly been discussing what lessons might be gleaned from previous environmental restoration efforts such as those for the Everglades, Chesapeake Bay and the Great Lakes.

These informal discussions over the past several months will now have to accelerate to meet Feinstein's goal, averred Thursday, of introducing a Delta bill by April.

"I think it can be a very helpful effort to provide the resources necessary," Costa said Thursday, stressing that "the precedent has been established" on some of the nation's other major environmental endeavors.

Boxer added Thursday that she supports "efforts to find comprehensive solutions to the water crisis that respect all stakeholders," and Rep. George Radanovich, R-Mariposa, said he was "pleased" that Feinstein was "putting her attention to this issue."

Still, the coming conflicts could be fast and furious.

Farmers and their allies insist the Endangered Species Act should be waived so that more irrigation water can be pumped. This is a deal killer for environmentalists. Radanovich, while generally praising Feinstein's efforts, stressed that a Delta bill "still doesn't take care of the agricultural season next year," while Rep. Devin Nunes, R-Visalia, dismissed Feinstein's past authorship of California environmental laws.

"I've never seen her write one that works yet," Nunes said Thursday, denouncing Feinstein's supporters as "radicals."

At the same time, Nunes added that "I believe that she wants to fix the problems." He noted that the energy and water bill approved 308-114 by the House on Thursday included a provision he worked on with Feinstein, permitting the Army Corps of Engineers to buy 24 acres in Tulare County for improvements to Success Dam.

An expression of interest, though, is not a guarantee of success.

In June 2007, for instance, Feinstein declared her intention to work with farmers and environmentalists in solving the irrigation drainage problems endangering the San Joaquin Valley's west side. Meetings were held but no discernible legislative progress was made.

Any California water bill, moreover, will take a long time.

In October 2004, for instance, Congress gave final approval to Feinstein's $395 million "Cal-Fed" bill designed to protect the Delta and enhance the state's water supplies. That bill took three years to pass, during which time it changed markedly.

In the years since, the Cal-Fed program has received decidedly mixed reviews despite hundreds of millions of dollars

Similarly, a modified San Joaquin River restoration bill won its final approval in March, 27 months after the first version was introduced.