101 NB Central San Rafael Harbor Bridge Replacement

MARIN COUNTY – Caltrans District 4 (Bay Area) is in the final stages of the Harbor Bridge construction project in San Rafael.

The work includes the replacement of the existing Central San Rafael off-ramp bridge over San Rafael Creek on the US-101 off-ramp to Second Street in San Rafael. The original bridge was constructed in 1941 and was widened in 1953. The bridge was determined to be structurally and seismically deficient. The new bridge will be realigned and widened to meet standards.

Caltrans started bridge replacement work in early February 2021.

The contractor completed constructing the eastern portion of the new bridge and switched traffic into construction detour in November 2021. Due to environmental restrictions for in-creek work, the project was suspended in December 2021.

Work on the intersection improvements started in May 2022 while in-creek work resumed in June 2022 to complete the western portion of the new bridge and switch to the final traffic configuration. The deck of the western portion of the new bridge and the bridge approach slab have been completed. In addition, the final in-creek work was finished.

Caltrans is currently working on intersection improvements. Temporary striping has been completed, and final striping will be finished once weather conditions allow. Intermittent closures along the Central San Rafael off-ramp will be needed at times.

In the case of ramp closure at night, two detours are being utilized:

Primary detour
Continue on northbound US-101 and take the northbound loop off-ramp to San Pedro Road
Take a right on Merrydale Road
Get on the US-101 southbound onramp
Take US-101 south to Mission Avenue
Continue onto Hetherton Street
Take a left on 2^nd Street

Secondary detour
From northbound US-101, take the Francisco Boulevard exit
Take a right on Bellam Boulevard
Take a left on Francisco Boulevard
Take a right on Grand Avenue

Total project cost: $23 million

Estimated completion: Early spring, 2023