VIRGINIA OFFICIALS ARE ironing out details of a high-occupancy toll lane project for a stretch of the Capital Beltway. It is no surefire solution to congestion, but it could be a start toward a helpful network of HOT lanes for the region. Virginia will work with a private partner to add two lanes to each side of the Beltway, separated from other traffic, between Springfield and Georgetown Pike. These lanes would be free for carpools of three or more people; others would pay. To keep these lanes from clogging, tolls would increase with the amount of traffic.

Given the sad state of funding for transportation, the public-private financing of money-generating highways is fast gaining support. As reported by The Post's Steven Ginsberg, most of the construction costs will be paid by the private partner, Fluor Daniel, though the state's exact obligation remains to be determined. In return for this investment, the company would make a profit on engineering studies and other preliminary work and possibly would receive a negotiated fee or a share of the toll revenue. These negotiations should be subject to close public review before a final contract is signed.

Maryland, too, is considering designating certain existing lanes for tolls as well as building HOT lanes. Plans began more than three years ago but were halted in mid-study when then-Gov. Parris N. Glendening (D) decided that allowing people to pay their way into the fast lanes was some kind of offensive class issue. This ignored the fact that existing high-occupancy-vehicle lanes -- paid for by everybody, drivers or nondrivers -- are underused. Also, experience in other states has shown that motorists of no great means often opt for HOT lanes when pressed for time. In such a system, other drivers benefit from the resulting reduction of traffic in the free lanes.

Gov. Robert L. Ehrlich Jr. (R) put Maryland back on track, citing tolls and other user fees as a necessary if partial answer to transportation funding. But Maryland and other states are still waiting to see what Congress agrees to in its pending transportation reauthorization bill. The House version of this legislation would allow only new lanes to be designated for high-occupancy tolls; the preferable Senate bill, which still needs clearer language, recognizes that existing lanes could and should be converted in some cases. There's reason to proceed cautiously with existing lanes, but federal restrictions should not preclude flexibility.

Maryland and Virginia are right to pursue HOT lanes, but they still must raise revenue -- gas taxes included -- to fund major, long-overdue road projects.