Key lawmakers are at odds on how to fix another consequence of soaring gas prices.

The federal trust fund that pays for highway and bridge construction and repairs runs on gas taxes and already faced a multibillion-dollar shortfall, even before fuel prices spiked above $4 per gallon. With Americans now buying less gas, the problem is exacerbated.

Industry officials and lawmakers fear the economic impact of lost construction jobs if highway projects around the country start grinding to a halt because the funds aren’t there to support them.

Rep. John Mica (R-Fla.), the ranking member of the House Transportation and Infrastructure Committee, worries that some of the projects already are stalled.

“[States] are not moving forward with projects because they are being told the money won’t be there,” Mica said. “We need every project to move forward to help stimulate the economy.”

Mica said Ways and Means Committee Chairman Charles Rangel (D-N.Y.) is taking the lead on the most recent plan to transfer more than $8 billion from general Department of Transportation funds to the highway trust account, replacing an amount moved from the highway fund to the general fund in 1998 when the trust was flush and running a surplus.  

Several attempts to get the $8 billion transfer passed into law in recent weeks, however, have failed.

In an interview, Rangel called the Highway Trust Fund fix a “must-do” before Congress leaves for its August recess. He said he and Senate Finance Committee Chairman Max Baucus (D-Mont.) met earlier this week to discuss a new approach but were distracted with the housing rescue and energy-related bills.

“It’s got to get fixed, but it’s very difficult,” Rangel said.

Last week Senate appropriators easily passed a fiscal 2009 transportation and housing spending bill that included language preventing the federal highway account from going into debt next year.

Senate Appropriations Transportation, Housing and Urban Development subcommittee Chairwoman Patty Murray (D-Wash.) said the $8 billion transfer would prevent a 34 percent cut in spending for highway projects.

But any attempt to fix the shortfall through spending bills is unreliable. Senate Majority Leader Harry Reid (D-Nev.) has said only two appropriations bills will be completed this year and the rest — including the transportation and housing bill — will be rolled into a continuing resolution lasting into next year.

Baucus and Senate Finance Committee ranking member Chuck Grassley (R-Iowa) have been trying to find a solution for more than a year.  

Late last month, Baucus and Grassley added language to the Federal Aviation Administration reauthorization bill that would have channeled billions into the fund. Sen. Jim DeMint (R-S.C.) blocked that attempt once the bill reached the Senate floor, arguing that the Highway Trust Fund fix should have been addressed in an earlier bill making technical corrections to the 2005 transportation measure. Instead of trying to find savings in that bill for the trust fund, members chose to add new earmarks, he argued.