Highway 101 Widening Project - Updates

On the morning of April 27, 2008, Caltrans opened the new connector ramp from southbound Highway 101 to eastbound Interstate 580. The new ramp marks a major milestone in the 101 Gap Closure Project, and is perhaps the most important new highway structure built in Marin County in the past fifty years.

The old connecting ramp, designed and built in the fifties, consisted of only one lane. For years, that one lane was sufficient. But by the nineties, the lane could no longer handle the steadily increasing volume of traffic. The two lanes on the new ramp will help ease the chronic congestion found at this intersection.

Only one lane is currently open. In order to finish the second lane, we must first demolish the old ramp, which is directly in the path of the second lane. Once the old ramp is gone, we will finish construction on the second lane. It should be open to traffic in early September.

Drivers will notice one important difference. The new ramp begins much farther north than the old one. Those who are headed south on Highway 101 with the intention of using the ramp should be prepared to exit much earlier than before. If they miss the new ramp, they have the option of continuing south on Highway 101, taking the Sir Francis Drake exit, turning left on Sir Francis Drake, and proceeding to eastbound Interstate 580.