Updated Thursday, January 10, 2013 at 07:18 AM
Facing steep declines in gas-tax revenues that pay for road repairs, Washington is exploring a creative solution: charging drivers by the mile to use state highways and roads.
A committee of transportation experts recently concluded it's feasible to move the state away from gasoline taxes to a "pay as you go" road-fee system.
"Now we're questioning: Is it acceptable for Washington, and if so, in what form?" state Transportation Secretary Paula Hammond said.
More than a dozen states have studied the idea, but so far no state has implemented it widely.
The gas tax has been the main source of money for highway maintenance and repair in Washington for decades. But revenues from the tax, a fixed amount per gallon, have been declining as residents drive fewer miles in more fuel-efficient cars.
Further steep declines are expected when Obama administration fuel-efficiency standards take effect, requiring the average gas mileage of all new cars and trucks be doubled by 2025.
"The gas tax is dwindling," Hammond said. "It would be irresponsible for us not to look ahead and take care of our system in the future."
Between 2007 and 2023, fuel-tax revenues are projected to fall by more than $5 billion, state estimates show.
Last year, the Legislature charged a steering committee with studying whether a road-user fee was possible and with recommending next steps. The state Transportation Commission is expected to finalize the committee's report later this month and ask state lawmakers for about $1.6 million in the 2013-15 budget to study how the idea would work.
"We're a long way yet from knowing whether it's a good idea," said Jeff Doyle, project director for the road-user charge assessment.
Hammond said it could be 10 years before the state implements any sort of road-user fee.
Still to be debated is how the fee would be charged — by miles driven, time spent on the road or another alternative, and how mileage would be reported or collected.
Options for collecting mileage include annual odometer readings, smartphone apps and equipping cars with GPS devices to track miles driven. The last is likely to raise protests from those concerned about privacy issues.