Forget the gas tax. One state lawmaker wants to bill drivers by the mile.

Democratic Senator Mark DeSaulnier of Concord has introduced legislation to test a tax for vehicle miles traveled.

It's mostly due to a drop in revenue from the current markups to maintain highways -- 52 cents per gallon.

People are driving cars that get better mileage.

It's not yet known what the new tax would be, but lawmakers could take a cue from a program in Oregon, which charges 1.5 cents per mile. This would be voluntary in 2016.

The DMV would have the authorization to track mileage in a yet-to-be determined city.