100-year-old bridge has been replaced, new design honors history

SAN LUIS OBISPO — The City of San Luis Obispo announced on Jan. 22 it successfully completed the Marsh Street Bridge Replacement Project, which significantly improved the safety of a major connection to the Downtown. Community members are invited to watch the virtual ribbon-cutting event here.

The bridge, located between Osos Street and Santa Rosa Street at the San Luis Obispo Creek crossing, has stood for over a hundred years, and in 2008, a bridge inspection by Caltrans determined that the bridge was structurally deficient to the point where repair or replacement was necessary which began in January 2020.

Revitalization of the bridge, a historic corridor into Downtown San Luis Obispo, is part of the City’s ongoing efforts towards Downtown Vitality. Preservation of historical features, safety enhancement, and stewardship of the environment were all achieved thanks to the diligence of the many agencies, designers, contractors, and City staff. “Marsh Street Bridge is an important connection point into the Downtown Area, and the new safety, environmental and design elements help honor the significance of this historic bridge,” said Public Works Director Matt Horn. “We want to thank the Downtown businesses for their patience during the project’s construction and hope this bridge continues to welcome residents and visitors to the Downtown.” 

The design of the bridge was started in 2013 with rigorous requirements for bridge safety, sensitivity to the adjacent businesses, and protection of the environment and wildlife surrounding the bridge. Along with the replacement of the bridge, an aging and deteriorating sewer main underneath the bridge was replaced with a more efficient line. To highlight the historical significance of the original bridge, energy‐efficient LED fixtures were installed that replicate the original kerosene fixtures that were lit along Marsh Street every evening. Also, the guardrail installed mimics the historic structure as well.


Constructing a bridge over San Luis Obispo Creek required coordination with the Regional Water Quality Control Board, State Department of Fish and Game, as well as the Army Corps of Engineers. The project featured a wildlife-friendly creek diversion, was completed within a single dry season, and required constant monitoring for protected species.

Funding for the improvements came from the Federal Highway Administration bridge replacement program, as well as matching City funds. The City coordinated with Caltrans to ensure smooth Federal funding and utilized Local Revenue Measure revenue to complete the project.

To receive updates from the City, please visit the City’s website at slocity.org