Highway 101 widening project complete through Marin-Sonoma Narrows, marking milestone for $1.5 billion North Bay project

"Just before dawn on Monday morning, Caltrans achieved a major North Bay milestone - although there are still a few signs on Highway 101 indicating otherwise. "Right Lane Ends" warned a sign facing southbound motorists a mile south of Petaluma's Kastania Road exit, just beyond a decommissioned gas station and the billboard for a long-gone "Cigarette Depot." Drivers can now feel free to ignore that warning sign, which, as of early Monday morning, had become obsolete. The lane in question now keeps right on going."

"Nor, despite identical, out-of-date signage, does the right lane on northbound 101, across the highway from the old Birkenstock building, come to an end. By sunrise Monday, that dreaded three-lanes-down-to-two bottleneck was a thing of the past. The opening of those lanes, and closing of those chokepoints, marks the completion of the Marin-Sonoma Narrows project, which focused on a 16-mile stretch of the highway between Novato and Petaluma. Work on that project began in 2011 and has cost an estimated $762 million."

"That undertaking was part of an even larger, roughly $1.5 billion public works project designed to create a continuous carpool lane from Sausalito to Windsor - a vision which, as of Monday, has now been realized. The removal of the final two pinch points along that 58-mile stretch represents a watershed moment for Caltrans, which announced in a release that "around 5 a.m. Monday morning" it had opened the long-awaited, continuous HOV lanes (third lanes) on Northbound and Southbound US-101."

Caltrans opened continuous northbound and southbound HOV lanes on US-101 early Monday, removing two final pinch points that had forced three lanes down to two. The openings eliminate outdated "Right Lane Ends" bottlenecks near Petaluma's Kastania Road and opposite the old Birkenstock building. The lane work completes the Marin-Sonoma Narrows project, a 16-mile effort between Novato and Petaluma that began in 2011 and cost about $762 million. The project was part of a larger roughly $1.5 billion effort to create a continuous carpool lane from Sausalito to Windsor. Suzanne Smith retired in 2023 after 26 years securing funds and now chairs The SMART Initiative.

Read at The Mercury News