House Republicans are trying a new approach to divert more water from Northern California.

Check that. They’re dusting off a stale and disreputable tactic: attaching a proposal that can’t pass on its own to unrelated legislation that has bipartisan support.

In this instance, they’re hitching a ride on Senate-approved energy measures that reached the House floor this week. One is a must-pass bill that contains $37.4 billion in funding for the upcoming fiscal year. The other is a broader energy policy bill.

These parliamentary maneuvers are further evidence that growers and water districts can’t justify what they want – more water at any cost, even jeopardizing endangered salmon and the North Coast communities that rely on fishing for their economic survival.

Northern California representatives have been locked out of negotiations as their Central Valley colleagues have produced one bad bill after another. Valley legislators, meanwhile, have ignored a science-based measure introduced by Rep. Jared Huffman, D-San Rafael.

Huffman made some progress this week on a related front, when a House committee voted to modernize management practices at dams managed by the Army Corps of Engineers, which would end the practice of releasing water from Lake Mendocino to protect against a flood that isn’t even in the weather forecast.

The GOP bill heads in the opposite direction: ordering more pumping of water to farms south of the Sacramento-San Joaquin Delta, which would threaten salmon runs as well as the environmentally fragile delta itself.

The legislation also would shrink a San Joaquin River salmon-and-habitat restoration program, mandate the sale of New Melones Dam on the Stanislaus River to local water districts and prohibit the use of federal money to purchase water to supplement flows for environmental purposes in river basins that have suffered from drought.

A stand-alone version of the water bill passed the House over the objection of environmental groups and Northern California congressional representatives. That measure stalled in the Senate.

Sen. Dianne Feinstein told McClatchy Newspapers that she doesn’t think the latest bill could pass the Senate either. The danger is that it could slip through if other issues in the energy legislation dominate the attention of a House-Senate conference committee.

Feinstein, who has tried for several years to broker a compromise, offered alternative legislation of her own earlier this year. Unfortunately, it also lacks adequate safeguards for the delta and the salmon whose continued existence is dependent on its restoration.

California may be past its most recent drought, but that doesn’t mean water supplies are unlimited. The state and federal governments have made a priority of protecting natural resources, including endangered species. That shouldn’t be abandoned to facilitate larger diversions to the Central Valley.

Residents still are being asked to conserve. But, as Los Angeles Times columnist George Skelton pointed out on these pages, California agriculture uses 80 percent of the state’s water, and growers kept planting thirsty nut trees throughout the drought while pressing, often in court, for maximum diversions and pumping groundwater at an unsafe rate.

Their bid for more water continues in Washington, but it’s time to tighten the tap.