Rail safety cost drops: Updated design for grade separation in San Bruno and South San Francisco saves critical dollars

Currently, the rail crossing at South Linden Avenue is the only at-grade crossing in South City, with Scott Street crossing in San Bruno less than a mile away, and the two cities have been working with Caltrain and the San Mateo County Transportation Authority on a separation project.

“It improves traffic circulation and mobility, it eliminates traffic delay caused by the gate downtimes at Linden Avenue, and it’s really focused on increasing public safety at both of these crossings for vehicles, people walking and people biking,” Patrick Gilster, director of Planning and Fund Management, said during the board meeting.

Originally, the project was going to elevate the tracks at Linden Avenue, slightly elevate them at the Scott Street intersection and close it to cars, creating a pedestrian and bike tunnel. The new plans are similar but instead of elevating the tracks at either intersection, the road will be lowered underneath the railroad at Linden Avenue. The Scott Street crossing will have the road closed to vehicles with a pedestrian and bike crossing instead. The changes will save about $130 million, with total project cost estimated to be about $320 million.

“This is really to remove the complex and costly parallel tracks,” Gilster said.

The cost savings is welcome news, given other grade separation projects, most notably at Broadway in Burlingame, have seen project costs spike, in some cases nearly double.

“Reducing the project by $130 million is really a big deal,” said Mark Nagales, board member and South San Francisco councilmember, during the meeting.

Caltrain and the cities of South San Francisco and San Bruno are also making financial contributions. The preliminary engineering phase is now expected to be completed in June 2027, construction will likely take two to three years.