Caltrans is scheduled to begin utility potholing on both directions of the full length of Tiburon Blvd. also known as State Route 131 (SR-131) in Marin County from the U.S. 101 exit to Main street (approximately four miles). Normal project work hours are 8:00 PM to 6:00 AM Monday through Friday and on Sundays.
Workers will perform potholing on SR-131 to safely locate underground utilities (water, electrical, gas, telecommunications, and fiber optic lines) in preparation for the upcoming paving project of SR-131 scheduled in 2026.
Eastbound and westbound lanes of SR-131 will be subject to one-way traffic control. Only one lane will be open at a time, with traffic alternating directions through the work zone.
All work depends on weather. Work will be completed tentatively by July 2025. Caltrans thanks the public for its patience and understanding as they work to maintain and improve our state's highways. For the latest road and highway conditions, click here.