WASHINGTON -- The federal government would revamp how it pays for firefighting and take some of the burden off the U.S. Forest Service by creating a permanent fund for devastating blazes, under legislation introduced Thursday by key House Democrats.

As wildfire seasons have grown increasingly expensive over the past decade, the cost of fighting fires has eaten an ever larger portion of the Forest Service budget -- now about 48 percent of it. That has left the agency with less money for other programs and priorities.

The new fund would be used only for catastrophic, emergency wildland fire suppression. It would be separate from the money budgeted each year by Congress for anticipated and predicted fire suppression activities for the Forest Service and Interior Department; that allocation would continue.

The amount of money in the new fund would be appropriated annually and based on the average amounts spent by the Forest Service and Interior to suppress catastrophic fires over the preceding five fiscal years.

Last year, the Forest Service spent $741 million more than budgeted and Interior spent $249 million more than budgeted for emergency wildfire suppression, or a total of nearly $1 billion.

The secretaries of the departments would be able to declare fires eligible for the fund by issuing a suppression emergency declaration that would evaluate the size, severity and threat of the fire.

The chairman of the Natural Resources Committee, Rep. Nick Rahall, D-W.Va., and the heads of the relevant subcommittees introduced the Federal Land Assistance, Management and Enhancement Act, or FLAME Act. Rahall said the Forest Service has been turned into the Fire Service.

"The dramatic rise in federal costs to fight these fires has eroded critical funding for non-fire programs and severely altered the core mission of our federal land management agencies," he said in a statement. "This legislation aims to turn this situation around."

The other sponsors included Rep. Raul Grijalva, D-Ariz., chairman of the National Parks, Forests and Public Lands subpanel, and Rep. Norm Dicks, D-Wash., House Interior Appropriations Subcommittee chairman.

The sponsors said 2 percent of fires, those that are not put out during the initial attack, today account for 80 percent of the costs to the agency.

The act would also require the Interior and Agriculture secretaries to submit a report to Congress one year after enactment containing a cohesive wildland fire management strategy.

That would include a system identifying the most cost-effective means for allocating fire management resources, a system for assessing the level of risk to communities, an illustration of plans to reinvest in nonfire programs, a description of use of appropriate management response, and a system ensuring that the highest priority fuels reduction projects are being funded first.

Sen. Max Baucus, D-Mont., introduced similar legislation in the Senate last summer.

That bill, the Stable Fire Funding Act, would authorize $600 million in seed money to create a trust fund for the Forest Service and $200 million in seed money for a BLM trust fund. That money would generate interest and be used to cover 80 percent of firefighting costs that exceed the agencies' annual budget.

He described it as a stop-gap measure that would kick in during some years but not others. More money would be added to the fund as necessary. The Senate bill remains in committee.

The Wilderness Society praised the House bill as "a key step in the right direction."

"However, this is only one part of the solution," said Jaelith Hall-Rivera, a wildfire policy analyst with the group. "We also need to continue to focus on managing fire cost-effectively, and probably most importantly, restoring our forests to a state where fire can once again play its natural role."