Train bridge project on track: Street closures begin as Caltrain replaces 100-year-old bridges in San Mateo

Strategically scheduled to avoid affecting thousands of the transit agency’s commuters, the Tilton Avenue bridge will be swapped out with a seismically safer version overnight Nov. 7.

Once the Tilton Avenue bridge is replaced and the road reopened, similar structures at Monte Diablo, Santa Inez and Poplar avenues will also be replaced and the roads closed one at a time for up to eight weeks a piece, according to Caltrain.

The $38 million project includes new retaining walls and the new steel bridges are being manufactured out of state before being assembled on site, according to Caltrain.

“The bridges are over 100 years old and they’re aging and they no longer meet the current seismic safety standards. So we have to upgrade these bridges for the safety of our passengers that ride on the train and for safer rail operations,” said Caltrain spokeswoman Tasha Bartholomew.

Not only do these four outdated bridges not meet today’s earthquake safety standards, they don’t provide for modern vehicles as large trucks frequently become stuck under the low-hanging structures, Bartholomew said.

“We’ve had many issues where trucks have gotten stuck thinking they could make it. So we’re hoping that by raising the tracks by up to 4 feet in some areas, depending on which bridge, that it will help with that issue which has been a concern for residents,” Bartholomew said.

The Tilton Avenue structure won’t gain any clearance since it’s the closest to San Mateo’s downtown train station where the tracks’ grading must remain the same.

However, the other three sites will be raised allowing larger vehicles to pass under the tracks, according to Caltrain.

In California, and particularly with the bustling Peninsula crossing various fault lines, many believe it’s only a matter of time before the next quake hits. Seismic upgrades to the long-standing bridges will provide benefits to residents and those driving through the neighborhoods, according to San Mateo City Manager Larry Patterson.

“The Caltrain project will result in safer bridges when the next major earthquake occurs. Additional clearance over the cross streets will also be provided. This will reduce disruptions to train service that occurs whenever a tall vehicle bumps one of the low bridges,” Patterson wrote in an email.

As part of the project that officially started with site and vegetation clearing in early 2014, retaining walls are being constructed to support the new higher and thicker structures.

Residents were concerned clearing vegetation around the bridges would unearth some unwanted vermin, which prompted Caltrain to require its contractor include vector control as part of its work, Bartholomew said.

Residents surrounding the San Mateo bridges have also experienced construction related to Caltrain installing positive train control, a state-mandated upgrade that will help prevent train-on-train collisions. That $231 million project is part of the Caltrain Modernization Program — a massive system overhaul slated to electrify the tracks between Gilroy and San Francisco.

San Mateo’s bridge replacements, while not directly affiliated with the modernization program, is part of Caltrain’s ongoing effort to update its infrastructure to account for current standards as it experiences consistent monthly ridership growth.

The regional transit agency is continuing to consider its San Mateo assets and is also in the midst of seeking a partner to construct a transit-oriented mixed-use housing development atop its Hayward Park Caltrain Station.

For now, the rotating street closures along Tilton, Monte Diablo, Santa Inez and Poplar avenues is officially underway and will include portions of Railroad Avenue also being shut to vehicle traffic.

Visit the projects and plans page at caltrain.com for more information and updates on the San Mateo Bridges Replacement Project.

samantha@smdailyjournal.com

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