HARRISBURG -- Increasing fuel prices are causing drivers to think twice before hitting the road, but the money they're saving could translate into trouble for the state's roads and bridges, which depend on fuel tax collections to fund repairs.

The state collected just over $1 billion in liquid fuels taxes for the first 10 months of the fiscal year, down $100 million, or 7.6 percent from the same time period last fiscal year.

"Not surprisingly, in the face of soaring fuel prices we are starting to see demand impacted and, yes, it does pose a concern because fuel taxes help pay for highways and bridges," said Rich Kirkpatrick, spokesman for the Pennsylvania Department of Transportation.

Liquid fuels taxes include the 31 cents per gallon on gasoline, 38.1 cents per gallon on diesel and an assessment on oil companies based on wholesale fuel prices. Together, taxes on liquid fuels account for about half of the Motor License Fund, which funds infrastructure repairs and helps pay for state police to patrol highways.

The rest of the fund comes from driver's license and registration fees, which are up for the year to date.

Overall, Motor License Fund collections have fallen 2.3 percent short of revenue projections for the year to date. Collections totaled $2.14 billion as of the end of April, or $49.5 million below projections.

Transportation officials are concerned.

"What happens if demand for fuel falls when you have a system of funding transportation systems that's largely dependent on those fuel purchases?" Mr. Kirkpatrick said. "We have to see how steep this drop-off will be and exactly what it means."

He said that embracing his boss Gov. Ed Rendell's plan to lease the Pennsylvania Turnpike would help.

Mr. Rendell wants to lease the turnpike to Abertis Infraestructuras, based in Barcelona, Spain, for 75 years. The state would collect $12.8 billion upfront and invest it, yielding a projected $1.1 billion a year in interest that would be used to fix roads and bridges and to fund mass transportation.

"We're struggling to deal with the largest number of structurally deficient bridges in the country, and the governor's Rebuild Pennsylvania program would be one way to address that," Mr. Kirkpatrick said. "It's an innovative way to generate $1 billion a year for transportation."

The plan is now before the state Legislature, where members of both parties already are criticizing the idea. House Transportation Committee Chairman Joe Markosek, D-Monroeville, and others prefer to pay for transportation needs by turning Interstate 80 into a toll road. That plan requires federal approval, and a ruling could take months. .....

In the short term, the PennDOT is analyzing the effects of reduced fuel-tax collections, Mr. Kirkpatrick said.

"We can't spend more on improvements than we have coming in in revenue," he said. "There won't be any impact on construction projects that already have been approved, but it is possible that future road and bridge projects might be delayed."

Pennsylvania isn't the only state where fuel-tax revenues are lagging. The Charleston Gazette reported Tuesday that they are down in West Virginia, too -- fell 7 percent short of projections last month. Some lawmakers there said the state needs to find alternative ways of funding highway construction.