States beset by falling tax collections from fuel sales are considering new sources of revenue, including increasing gasoline taxes and adoption of taxes based on miles traveled, USA Today reported Friday.

At least 13 states are considering proposals for new revenue sources as stagnant federal and state gasoline taxes cannot keep pace with funding requirements for maintenance of highways, bridges and other infrastructure, the paper said.

Sixteen states have not raised gas taxes in at least 20 years, USA Today reported, citing the Institute on Taxation and Economic Policy, a think tank.

Oregon, Washington and Vermont are among the states considering replacing or supplementing gas taxes with taxes on vehicle-miles traveled, the newspaper said. Meanwhile, several states have set a host of innovative funding proposals to make up for gas tax shortfalls.

One, from Virginia Gov. Bob McDonnell (R), would eliminate the state’s gasoline tax and replace it with a higher sales tax to pay for transportation projects. And Virginia is one of several states — others are Pennsylvania, Massachusetts and Michigan — that is considering higher sales taxes or new taxes on filling stations, higher motor vehicle registration fees and adding more tolls, USA Today said.