WASHINGTON -- With large portions of the 46,000-mile Interstate Highway System wearing out and needing replacement, but with few federal and state dollars to do it, one possible solution goes back to how most roads were originally built: tolls.
Fuel taxes aren't keeping up with growing highway maintenance needs, forcing states and the federal government to look for alternatives -- and tolls are part of the mix.
The libertarian Reason Foundation released a study Thursday that proposes tolling the entire interstate system, charging 3.5 cents a mile for cars and 14 cents a mile for trucks, adjusted every year for inflation.
Under federal law, new interstates can be tolled, but existing ones can't, and Congress would have to change it. But it could be a tough sell to a public long accustomed to freeways.
"Tolling is not something that many motorists want," said Michael Green, a spokesman for AAA. "They feel, in their mind, that they've already paid for those roads."
In some ways, they did. Starting in the 1950s, the highway trust fund was established to fund the construction of interstates with revenue from the federal gasoline tax, which all motorists paid every time they filled their tanks.
Now, the oldest parts of the system are reaching the end of their design life, and the tank is almost empty. Congress hasn't raised the federal gasoline tax of 18.4 cents a gallon in 20 years, and the tax has lost a third of its value to inflation. People are driving less and cars get better mileage, further reducing the revenue collected at the gas pump.
The International Bridge, Tunnel and Turnpike Association estimates that it would cost from $1.3 trillion to $2.5 trillion to rebuild the entire interstate system over the next 50 years. The highway trust fund has been steadily paying out more than it takes in. The Congressional Budget Office projects that it could go broke next year.
"The gas tax is clearly on its last legs," said Bob Poole, director of transportation policy at the Reason Foundation and the author of the tolling study.
Under a pilot program, the U.S. Department of Transportation currently allows three states to levy tolls on existing interstates: Missouri, North Carolina and Virginia, although none of them do so. Mr. Poole wants Congress to allow every state to have that right.
He proposes that the users of the interstate system pay for its rebuilding with electronic tolls collected on a per-mile basis. A driver of a two-axle passenger car who crosses Pennsylvania from the Delaware River to the Ohio border -- roughly 350 miles -- would pay about $12.25 for the trip. A truck driver would pay about $49.
Compare that with the current cost of crossing the Keystone State on the Pennsylvania Turnpike, one of the country's first superhighways and a forerunner of the interstate system. The car driver pays $30.77, while the driver of an 80,000-pound, five-axle truck pays $160.96.
To address concerns of double taxation -- having to pay a fuel tax and a toll -- Mr. Poole proposes a fuel-tax rebate for interstate drivers, who would be reimbursed electronically through the same system that collects the tolls.