The California Department of Transportation (Caltrans) is exploring the feasibility of deploying high-speed buses capable of reaching up to 140 mph on the state's freeways. This concept, if realized, could revolutionise long-distance travel across the Golden State, offering a faster and potentially more affordable alternative to conventional bus services.
Proposed Network and Travel Times
Under the preliminary plan, a statewide network of dedicated bus lanes and purpose-built transit hubs would connect major urban centres, including Sacramento, the Bay Area, Los Angeles, and San Diego. The service would utilise long-distance express buses designed to move passengers efficiently between regions. During a recent Caltrans webinar, planners estimated that buses travelling at approximately 120 mph could complete the journey between San Francisco and Los Angeles in about three hours and 12 minutes, a significant reduction from the current driving time of roughly six hours.
Infrastructure Challenges
However, a preliminary assessment by Caltrans found that most U.S. freeways are engineered for speeds of up to about 85 mph. Implementing significantly faster bus services would therefore require extensive upgrades to roadways and infrastructure, including dedicated lanes, redesigned vehicles, and advanced safety technologies. Researchers emphasised that achieving such speeds safely would likely depend on automated driving systems, enhanced braking capabilities, and vehicle-to-everything communication systems to improve coordination and reduce risk.
International Models and Potential Corridors
As part of the research process, Caltrans is examining international models such as Australia's Adelaide O-Bahn busway system and the Netherlands' Superbus prototype. Officials have identified several potential corridors for future service, including Interstate 80, Interstate 5, U.S. 101, and State Route 99, which connects major Central Valley cities like Bakersfield, Fresno, Modesto, Stockton, and Sacramento.
Cost and Implementation
Caltrans noted that station construction would likely be the most expensive component of the project. However, costs could be partially offset through joint development projects, such as building stations over sections of existing freeways. Mehdi Moeinaddini, senior transportation planner at Caltrans, stated that high-speed buses could provide some of the speed advantage at a lower cost using existing freeway corridors once the technology matures. He emphasised that the proposal is in the early research stage and could serve as a complementary option alongside existing rail solutions, not a replacement.
The Independent has contacted Caltrans for further comment.
