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ACE Project Description

Fullerton Road Grade Separation Project
Fairway Drive Grade Separation Project
Nogales Avenue Grade Separation Project

The Alameda Corridor-East (ACE) Construction Authority was established in 1998 by the San Gabriel Valley Council of Governments (SGVCOG) as a single-purpose construction authority to implement a construction program intended to mitigate the vehicle delays and collisions at rail-roadway crossings resulting from growing freight rail traffic in the San Gabriel Valley. The ACE Trade Corridor rail mainlines through Southern California carry 16 percent of all oceangoing containers in the United States and have been designated by Congress as a Project of National and Regional Significance. With trade volumes through the Ports of Los Angeles and Long Beach projected to grow, train counts through the Valley are expected to increase by 150 percent by 2042, resulting in additional adverse crossing impacts. In 2017, the SGVCOG was restructured, and established the SGVCOG Capital Projects and Construction Committee as a successor to the ACE Construction Authority with full responsibility for implementing the ACE Project.

The ACE Project is a comprehensive program of constructing grade separations where the road goes over or under the railroad at 19 crossings (resulting in the elimination of 23 at-grade crossings) and safety and mobility upgrades at 53 crossings. Construction has been completed on sixteen rail-roadway grade separations. One grade separation is under construction, with another two grade separations and eight crossing safety projects in the design phase. Jump Start safety improvements have been completed at 40 at-grade crossings.

Project Benefits

Baldwin Avenue Grade Separation Project
Ramona Boulevard Grade Separation Project
Nogales Avenue Grade Separation Project (North Facing)
  • Eliminates passenger vehicle and truck delay at the grade separations and reduces roadway network congestion near the grade separations, reducing emissions in the worst air basin in the nation caused by idling vehicles waiting for trains to pass.

  • Eliminates collisions between trains and motorists, cyclists and pedestrians at the crossings to be grade separated and improves safety at the remaining at-grade rail crossings.

  • Reduces or eliminates emergency responder delay at the crossings to be grade separated.

  • Facilitates locomotive horn-free rail “Quiet Zones” in communities surrounding the grade separations resulting in positive impacts on residential property values.

  • Improves reliability and capacity of train operations by eliminating at-grade collisions on freight railroads with shared Metrolink commuter and Amtrak intercity train operations.

  • Improves the state of good repair of the freight transportation system by replacing aging rail-roadway crossings with new grade separations.

  • Sustains the growth of freight movement and associated economic sectors in Southern California, the nation’s largest trade gateway and inland corridor, while reducing the impacts of increased freight rail traffic through San Gabriel Valley communities.

Project Goals


Increased Safety

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