Dam bridge inches closer to completion

Having worked on the project for decades, San Mateo County engineer Gil Tourel said he’s received many questions about why it’s taken so long to rebuild the 616-foot-long, 51.5-foot-wide bridge where the Crystal Springs Reservoir meets the San Mateo Creek, especially since the reconstruction has led to a yearslong closure of this section of Highway 35, also known as Skyline Boulevard.

Now that they are starting to lay plans for the last few components of the project, Tourel said it’s been gratifying for those involved in coordinating the multi-faceted project over the years to see it near completion.

“It’s kind of surreal for all of the folks involved,” he said. “It’s been out there for so many years.”

Tourel said the lengthy timeline for the project has less to do with the bridge’s length and more to do with its unique location on top of a dam connected by miles of tunnels to the Hetch Hetchy Reservoir. To ensure no debris falls into a critical piece of the region’s water infrastructure, Tourel said close coordination between the San Francisco Public Utilities Commission, which owns and operates the dam, PG&E and the county’s Public Works and Parks departments was required. He added aspects of the project also required use of specialized equipment or techniques, noting the contractor the county hired to work on the bridge improvements was not permitted to use a barge to build the bridge and instead worked on the project from either side of the dam.

But it hasn’t just been the intricacy of the project that’s extended its timeline. Tourel said a series of delays — including efforts to protect threatened species such as the California red-legged frog, a temporary freezing of federal funding behind the project and design changes prompted by discovery the actual dam extended further under the road than was originally believed — have contributed to the project’s timeline.

Charged with reinstating the road atop the spillway, realigning the approaches and creating the new route about 9 feet higher than before, county officials have been focused on improving passage on the bridge, which will include a new 15-foot-wide pedestrian trail safely protected from two lanes of vehicular traffic, said Tourel. With a price tag of more than $13 million, not including design costs, the bridge is largely complete with minor projects like restriping the road remaining.

Before work on the bridge could start, county planners coordinated with SFPUC officials working to more than double the capacity of the spillway in compliance with new state and federal standards, a project completed in 2012 to the tune of $35 million, according to the utility. Tourel said coordinating between the different agencies involved in the project’s many components — which also includes an effort currently underway on PG&E’s part to relocate high-voltage transmission lines previously supported by towers placed on either side of the bridge to another location under the bridge — has required they space their work out so only one group is working on the area at a time.

Tim Ramirez, the SFPUC’s director of natural resources and lands management, said he is looking forward to the opportunities presented by the project’s proximity to the some 15 miles of recreational trail included in the Crystal Springs Regional Trail, expected to extend another two miles to connect San Bruno to Woodside. In bringing more visitors to the watershed and engaging in efforts to protect native thistle and other wildlife near the San Mateo Creek, Ramirez said he expects public education opportunities to continue to open up alongside the well-used trail.

“It’s extremely popular with the community locally,” he said. “That’s great because it’s a chance to people to get out on the watershed.”

Acknowledging the challenge of maintaining the water quality even with more visitors to the area, Ramirez said the utility would work with county parks officials on an ongoing basis to ensure those using the trails are staying on them and enjoying the views from a distance. With 430,000 people visiting the Crystal Springs Regional Trail each year, officials are eager to complete a gap in the regional trail just south of the bridge, said County Parks spokeswoman Carla Schoof.

Expected to cost an estimated $1 million, officials are hoping to start and finish the segment in 2019 after they select a contractor later this year, said Schoof, who confirmed a 0.93-milelong connector trail south of State Route 92 is still in the works due to the presence of the California red-legged frog, which is a threatened species, and because funding has yet to be identified for it.

Though several items have yet to be checked off planners’ lists before they can open the trail, Schoof said they’re looking forward to spreading the word once it’s complete.

“I definitely feel that like there is anticipation for this to be done and for people to have access to the trail,” she said.

anna@smdailyjournal.com

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