New HOV lanes 52-miles long open along Highway 101 in North Bay

SAUSALITO, Calif. (KGO) -- Some long-awaited relief from some of the worst bottlenecks on Highway 101 in the North Bay.

On Monday morning, Caltrans officially opened new HOV lanes on both sides of the freeway between Sausalito and Windsor.

The new lanes are part of a major project aimed at improving commute times.

It's part of the the Marin-Sonoma Narrows project.

The new lanes are at the the Northbound section of Highway 101 just north of Atherton Avenue and Southbound, just below Kastania Road.

"It's added HOV lanes over the stretch in Marin and Sonoma County and obviously the goal is to improve congestion," said Caltrans Spokesperson Matt O'Donnell.

The newest lanes officially opened early Monday morning.

Caltrans saying that the work is getting done just in time.

"They got it done on Monday morning, by around 5 a.m., so crews had worked over the weekend, even on Sunday, to get this done, because there was a little bit of a rain in the forecast," O'Donnell said.

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Now with that work finished, drivers can now travel three continuous lanes through the stretch that's been known as the narrows.

"Moving forward, you have three lanes all the way through," O'Donnell said, "So that's now 52 miles of continuous HOV lanes"

The third lane isn't the only change drivers are now seeing as part of the Marin-Sonoma Narrows project.

New carpool lane hours went into effect in early September: 5 a.m. to 10 a.m. and 3 p.m. to 7 p.m.

Something that Caltrans admits has had a mixed reception.

"A lot of people are getting used to that, we're still getting used to that. We're still kind of monitoring the traffic patterns across Marin and Sonoma counties," O'Donnell said.

That change coming as drivers with clean air vehicle tags will no longer be able to drive in HOV lanes if they're alone starting October 1.

Caltrans said they are expecting changes in traffic patterns along the roads in light of that.

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For now, the agency said that the Marin-Sonoma Narrows project isn't over yet.

Crews will still be out at night finishing work and keeping track of how the new lanes impact traffic patterns.

"They're still kind of finalizing some things, and that will continue, for a little while. So, you know, people should expect to see crews out there," O'Donnell said.

Caltrans is encouraging everyone to carpool or use transit to take advantage of the new HOV lanes.

And as crews work overnight, drivers also asked to use extra caution along the roadways.