Caltrans this week opened a new southbound carpool lane on Highway 101 in Novato and in a couple of weeks plans to open a northbound carpool lane there.

Both are signs that the widening of  101 from northern Marin County to northern Petaluma is inching along, although closing the carpool gap will take years to finish.

The new southbound lane runs from Novato Creek to Highway 37. The northbound lane is to open Aug. 9 from Highway 37 to Atherton Avenue. The construction of  both, which are the fourth lane in each direction, cost a total of $49.3 million and took about a year to do.

Marin’s carpool-lane hours are 6:30 to 8:30 a.m. southbound and 4:30 to 7 p.m. northbound.

The highway’s widening in Marin is scheduled to continue later this year with crews beginning work to extend the southbound carpool lane from Atherton Avenue to Novato Creek and the northbound lane from Atherton Avenue to a bit south of the Redwood Landfill dump. Completion is scheduled for fall 2013.

After that, the next stretch of 101 likely to be widened is from about the Petaluma Auto Mall to a bit south of East Washington Street in Petaluma. Caltrans spokesman Steve A. Williams said that project is being designed with construction expected in 2015 or later, depending upon funding.

Future projects to widen 101 south to Novato is awaiting funding for design work and later construction, he said.

If you commute through Marin, drop us a comment below to let us know what you think of the new lanes.


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