WASHINGTON — Raise federal gasoline taxes to help pay for road projects?

Not during a recession, Transportation Secretary Ray LaHood has said.

Then how about moving toward a system that finances highway construction by charging motorists by the mile?

When LaHood suggested last week that be considered among other potential financing schemes, he got bushwhacked by the White House. "It is not and will not be the policy of the Obama administration," the president's press secretary said.

With the administration's position seemingly clear, a special commission created by Congress is nonetheless endorsing those two ideas.

Its report Thursday warns that if government fails to find a new way to raise money, "we will suffer grim consequences in the future: unimaginable levels of congestion, reduced safety, costlier goods and services, an eroded quality of life, and diminished economic competitiveness as a nation."

The National Surface Transportation Infrastructure Financing Commission says the current 18.4 cents a gallon gas tax and 24.4 cents a gallon diesel tax are not raising enough money to keep pace with the cost of highway, bridge and transit projects. The commission proposes lifting the gasoline tax by 10 cents per gallon and the diesel tax by 15 cents per gallon, and adjusting both for inflation.

The report also says fuel taxes increasingly will become a less reliable way to pay for highway construction as people drive more fuel efficient vehicles and the number of electric and alternative fuel cars and trucks grows.

Last fall, Congress transferred $8 billion from the general treasury to the highway trust fund to make up for a shortfall between revenue and money promised to states for highway projects. Last week, LaHood said a vehicle-miles-traveled tax was an idea that should be considered.

The report recommends moving to such a tax, which would mean equipping cars and trucks with a device that uses GPS technology to track the number of miles driven and compute the tax owed.

Commission members said the transition to a national system would take about 10 years.

Advocates said the tax is environmentally friendly because it encourages motorists to drive less and that technology solutions are available for any privacy concerns.

Commission member Geoffrey Yarema, a Los Angeles transportation lawyer, said the commission examined more than 40 types of funding schemes before arriving at a consensus that a mileage-based system makes the most sense.