Grade Separation

A grade separation is a roadway that is re-aligned over or under a railway to eliminate hazards. Benefits of grade separations include:

• Improved safety
• Reduced noise (no train horns)
• Decrease in traffic congestion
• Reduction in GHG emissions from idling vehicles
• Improved train operations reliability

In the Central Valley, where trains will be capable of running at speeds in excess of 200 miles per hour, the high-speed rail system is being built fully grade separated. As part of this effort, many existing grade crossings with existing freight service will be eliminated. Within the first three construction packages, stretching approximately 119 miles from Madera to north of Bakersfield, there will be a number of existing BNSF Railway and Union Pacific Railroad at-grade crossings eliminated. This will result in major improvements to both urban and rural areas in the Central Valley. ​

In Northern California, as part of the environmental work being done to identify the final high-speed rail alignment from San Francisco to San José, the Authority is working with communities to accommodate a blended system with Caltrain. This blended system is currently being evaluated for traffic, safety and noise impacts at existing at-grade crossings.

In Southern California, key early grade separation projects will include Doran Street and Rosecrans Avenue/Marquardt Avenue grade crossings. In addition to these critical efforts, the Authority is also partnering with various local agencies to evaluate other high-priority at-grade crossing projects in order to deliver safety and environmental benefits prior to the arrival of high-speed rail.