Future 'greenways' will be private-public ventures.(Brief Article)(Statistical Data Included)

The bust-to-boom history of the Dulles Greenway continues to affect the prospects for privately financed toll roads, even though the Greenway has fully recovered from its shaky start.

When the Greenway was completed in 1995, the 14.2-mile extension of the state-owned Dulles Toll Road was the nation's first privately built toll road in a century.

Some experts think it may be the last.

"Any roads of this type that would be built in the future will be public/private partnerships," said Rick Froehlich, the Greenway's chief financial officer. "You won't see any more roads built with purely private financing."

The Greenway's ridership has quadrupled in the last four years, but even that remarkable rise …