"About 70 percent of the construction and maintenance costs of Interstate Highways in the United States have been paid through user fees, primarily the fuel taxes collected by the federal, state, and local governments."
And about 1/7 of the fuel tax revenue is redirected to public transit, rather than highways.
A moderate increase in the fuel tax[1] could make the IHS completely self-sustaining for both capital and maintenance expenditures. Unfortunately, raising the gas tax is typically a political loser.
Local roads are predominantly paid for through local property and other taxes, but that's easier to justify, since everyone takes advantage of local roads even if they don't drive.
[1] At least until electric cars become commonplace, in which case I'd probably be in favor of a simple mileage tax which could achieve the same effect.