California State Route 91 HOT Express Lanes

Managed lanes begin as a trend and serve as a worldwide model



•    Facility is world’s first HOT lanes 
•    Lanes are the first congestion-priced facility 
•    The project was financed through a P3

Born from the need for congestion relief on Orange County’s State Route 91 when no public funds were available, the 91 Express Lanes are the world’s first high-occupancy vehicle toll facility and the first such project to use a public-private partnership financing model. The groundbreaking concept, engineered by HNTB, allows single-occupancy vehicles to use carpool lanes for a fee.

Involved in the project from inception, HNTB performed conceptual design, developed preliminary plans and cost estimates, created toll operating concepts, estimated operation and maintenance costs and provided necessary engineering to determine the financial viability of this project. 

The 10-mile stretch of four HOT lanes, built in the median of SR 91, opened in 1995, becoming the first U.S. congestion-priced facility, where tolls vary according to the time of day to guarantee free-flow speeds and reliable travel times. 

The facility has contributed to major advances in the toll industry worldwide.