Friday, Jan 11, 2019
 by 
Christa Bigue
  • Crystal Springs Dam Bridge

    When the Crystal Springs Dam opened in 1888, Benjamin Harrison was the nation’s 23rd president, National Geographic magazine published for the first time and gasoline-powered automobiles were in their infancy.

    After 130 years, much has changed in the world but the concrete gravity arch dam in unincorporated San Mateo County that served as a model for the Hoover Dam is significantly improved and with a new bridge that re-opened Skyline Boulevard to bicyclists, pedestrians and vehicles of all engine types.

    The County of San Mateo Public Works and Parks departments, the San Francisco Public Utilities Commission (SFPUC) and other critical partners gathered Friday, Jan. 11, 2019, to celebrate the highly anticipated completion of the multi-faceted project which includes critical safety and water capacity improvements to the dam and provides new travel opportunities on the bridge and adjacent recreational trails.

    County Supervisor Dave Pine told the assembled crowd that the multi-faceted project would not have been possible without close collaboration by several entities including the SFPUC which owns the dam, the County’s Department of Public Works (DPW) which replaced the entire bridge on top of the dam, County Parks which constructed the new trail segment and PG&E which relocated high-voltage transmission lines to the bridge’s underside.

    “This watershed is among the most beautiful views in San Mateo County and I’m proud of the partnerships that made strengthening the dam and reopening the bridge possible,” Pine said. “It’s exciting after so long to see the first visitors travel across.”

    The Lower Crystal Springs Dam crosses San Mateo Creek, forming the Upper and Lower Crystal Springs Reservoirs and is part of the SFPUC’s Hetch Hetchy Regional Water System. The structure is a concrete gravity arch dam, engineered in a way that revolutionized the dam and concrete industries and served as a model for Hoover Dam. Skyline Boulevard, also known as Highway 35, runs over the dam and has been closed to auto traffic between Crystal Springs Road and Bunker Hill Drive due to the interconnected projects needed to improve the dam and road.

    State Sen. Jerry Hill, D-San Mateo, who served as a San Mateo County supervisor when the project plans were still on the drawing board, was excited to mark its completion.

    “This is not just a celebration of the completion of an important project. It’s a new beginning for one of our county’s most extraordinary recreational and environmental resources,” Hill said.

    From 2010 to 2011, before the SFPUC could begin its $35 million in renovations, DPW removed the original 1920’s era bridge from the top of the dam. That same year, the SFPUC began its improvements which include doubling the width of the spillway to 200 feet and raising the parapet wall on top of the dam by 9 feet. Construction of the dam finished in December 2012.

    “More than one million people on the Northern Peninsula depend upon the drinking water stored in the reservoirs in this watershed,” said Steven Ritchie, the SFPUC’s assistant general manager for water. “By working together with our San Mateo County partners, we have been able to upgrade and maintain these crucial facilities for future generations.”

    Meanwhile, the Board of Supervisors approved $13.1 million for the new bridge which is reimbursed with Federal Highway Bridge Replacement and Rehabilitation Program funds. Construction began in February 2016 and the new bridge includes a separate section for Crystal Springs Regional Trail users to connected to a new “South of Dam” trail section completed in 2015. Major construction finished in October 2018 with finishing touches made in the months leading up to Friday’s celebration.

    The complexity of the interconnected projects was further challenged by its location in an environmentally sensitive area that houses the dusky-footed wood rat, California red-legged frog and San Francisco garter snake.  But despite the hurdles, everyone involved lauded the outcome.

    “There’s no question everyone involved had a lot to contend with on the road to success but I’m proud to say we did it and thankful for the patience of the community which has been so eager to see it complete,” County Public Works Director Jim Porter said.