Nearly a decade of experience in San Diego and Orange County, Calif., has shown that you can keep traffic flowing smoothly, at the speed limit, even during the busiest rush hours. How? Charge a toll, varying by the density of traffic in the lane, for drivers to use the high-occupancy vehicle lanes (HOV). These high-occupancy toll (HOT) lanes — on I-15 in San Diego and SR 91 in Orange County — have been a big hit with drivers in all income groups.
The next step is to apply this to mass transit. The idea is to reserve a portion of an HOV lane for buses and vanpools, while selling the remainder of the lane's capacity to motorists at market prices. The result is a virtual exclusive busway — a VEB.
A single lane can handle 1,700 vehicles an hour without congestion. In every metro area but New York, however, it would be very difficult to fill enough buses to operate more often than one per minute (60 per hour). There's room for about 1,600 additional — paying — cars per hour without interfering with the high-speed flow of buses and vanpools. That's a lot of toll revenue — in some cases enough to pay the cost of building an additional lane.
A VEB would be a better use of costly new highway lanes than two-person carpools. Most carpoolers turn out to be family members who would travel together anyway, so they don't reduce the number of cars by very much. We can make lemonade out of these lemons by converting HOV lanes to super-HOT lanes, dedicating a portion of their capacity to express bus service.
This is not pie-in-the-sky. Houston is already adding four HOT lanes in the median of the Katy Freeway (I-10), with part of their capacity reserved permanently for buses, vanpools and three-person carpools. Toll rates will be charged and kept high enough to limit other car traffic to what is compatible with uncongested conditions.
The moral of the story: VEBs are a good deal for hard-pressed transit agencies — and an even better deal for taxpayers.
Robert W. Poole Jr. is director of transportation studies and founder of the Reason Foundation.