Starting September 25, Two Lanes Closed For Richardson Bridge Project


Work will be 5 p.m. until 8 a.m. on Sunday

SAUSALITO — Caltrans will start construction on the Richardson Bridge project on September 25 along US-101 Northbound in Marin County. The construction work will involve the replacement of the existing asphalt concrete bridge deck surface with polyester concrete in both the northbound and southbound directions of US-101 at Richardson Bay Bridge. The closure starts near the Rodeo Avenue off-ramp and ends right before the Seminary Drive off-ramp.

Grinding of the asphalt and placing polyester concrete overlay will start on Sunday, September 25:

  • The two far-right lanes (No. 4 and 5 lanes) will be closed from 5 p.m. until 8 a.m.
  • The three left lanes (No. 1, 2 and 3) will remain open. The closure starts near the Rodeo Avenue off-ramp and ends right before the Seminary Drive off-ramp.
  • Drivers should expect delays in the evening hours of September 25 and use alternate routes like the San Rafael/Richmond Bridge and the Bay Bridge if possible.

The project will continue with grinding of the asphalt and placing of the polyester concrete on Monday, September 26, through Friday, September 30, from 8 p.m. until 8 a.m. each day. There should be minimal delays due to the time of construction.

The bicycle lane on the US-101 northbound shoulder will be shut down during construction hours. Cyclists should take a detour to US-101 southbound onto the Mill Valley Sausalito bike path, take a right on Hamilton Drive and a left on Redwood Highway Frontage Road. Detour signs have been posted.

Residents in the area may experience noise and some dust due to the work. The need for the project is to preserve the existing bridge and to decrease the probability of costly repairs in the future.

Changeable message and directional signs will be in place to assist motorists traveling in the area. The California Highway Patrol (CHP) will be on-site during the closures.

Please drive with caution. Slow for the Cone Zone and Be Work Zone Alert. Caltrans thanks motorists for their patience while we work to maintain our state's highways, bridges, and tunnels.

Additional project information is available at:
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Map showing the location on US 101 of the Richardson Bridge Project in Marin County.