Tolling for lane privileges
In 1994, the Colorado Department of Transportation (CDOT) opened reversible, high-occupancy vehicle (HOV) lanes along a seven-mile stretch of Interstate 25 between downtown Denver and U.S. Highway 36. In the peak hours, the I-25 HOV lanes carried more people per lane per hour than the adjacent general-purpose lanes. However, the HOV lanes carried fewer vehicles, resulting in significant unused capacity.
Recognizing that the HOV lanes could carry more vehicles and offer more choice and convenience for more drivers, CDOT began to consider changing them to high-occupancy toll lanes (HOT) that would allow solo drivers to pay to use the HOV lanes. Carpools, buses and motorcycles could continue to use the lanes toll free. State legislation passed in 1999 allowed CDOT to make the change.
In June 2006, the new I-25 HOV/tolled Express Lanes opened, allowing enough solo drivers in the lanes to use the spare capacity without slowing carpools and buses. To ensure solo drivers do not congest the lanes, bus travel time is monitored and toll rates are adjusted at various times of the day. During peak hours, the toll is higher than at other times.
Tolls are collected electronically to move traffic efficiently. Motorists with transponders drive under an electronic toll reader, and the toll is deducted automatically from their accounts. License plate photo technology and on-site law enforcement help enforce the tolls.
Since their introduction, the HOT lanes have been meeting first-year revenue and user projections. The lanes carry approximately 33,000 people per day, representing between 10 and 15 percent of the total trips along that stretch of I-25. The vehicles travel at full highway speeds, bypassing congested lanes.
CDOT expects toll revenues to cover operations, snow removal, maintenance and reconstruction costs, totaling nearly $1 million annually. “These lanes are significant in that they represent a new way of thinking about transportation,” says former Colorado Gov. Bill Owens. “Rather than building out and building more, we built in. We took an asset we already had, improved it and created an additional source of revenue without raising taxes.”
Stacey Stegman, public relations director, Colorado Department of Transportation
High-occupancy toll lane conversion
Tolling Enterprise Division of the Colorado Department of Transportation (DOT)
Colorado DOT, Regional Transportation District, Federal Highway Administration, Federal Transit Administration, Denver Regional Council of Governments, City and County of Denver