The Paradox Of The Dulles Toll Road

Tolls on the Dulles Toll Road will be going up by 25 cents next week to pay for the extension of Metrorail out to Dulles Airport. But this increase poses a bit of a problem.

There's a paradox involved in all Toll Roads: If you want them to generate more money, you raise the tolls -- but then fewer people use them, so you have to raise the tolls even more. Then even few people use the road...and so on and so on.

"That often will happen when you raise the prices on anything," says Tara Hamilton, a spokesperson for the Metropolitan Washington Airports Authority, which owns and operates the Dulles Toll Road.

She says toll hikes won't affect demand that much.

"We do anticipate that, but we don't think that it would be a major impact on the expected revenue," Hamilton says.

And to pay for the new Metrorail line out to Dulles Airport, they're going to need a lot of revenue -- more than $5 billion. The Airports Authority's finance plan projects toll increases of around a quarter every year for the next 35 years.