photo credit: Caltrans District 4

Soon enough the Novato Narrows won't be so narrow anymore.

Final phases of a long-awaited widening project are underway, and as part of the work Caltrans is shifting the traffic flow this weekend.

“Basically on Saturday, the southbound traffic will be moved to a temporary alignment and travel on the new construction in the median,” said Matt O’Donnell, Caltrans spokesperson for District 4, which includes Marin and Sonoma counties. “Crews will then begin construction on the future southbound final alignment. So that's a big, big step for this project.”

The temporary lane closures will take place between 8 PM and 4 AM. 

“This is all-night work. All this will affect people traveling at night as far the work over the weekend is concerned,” O’Donnell told KRCB News Friday mid-morning.

The southbound on and off ramps at San Antonio Road will be closed as well.

O'Donnell said once completed, the new raised lanes should make for an easier drive.

“Elevated lanes basically should improve sight for the drivers, and then it's also expected to help with drainage. You know, for when the storms come, it'll drain a lot easier than it did previously,” O’Donnell said. 

As for the Novato Narrows moniker, O’Donnell said it will eventually be a thing of the past. 

“When the project is complete, I guess we won't be talking about the Marin Sonoma Narrows anymore, or we'll refer to it, but as in the past. People hopefully will just be talking about the HOV [high occupancy vehicle] lanes and hopefully traffic will move through that corridor a lot easier.”

Caltrans expects to complete the final widening of that stretch of 101 and open three lanes in each direction in the summer of 2025.