City Takes Steps to Reduce Traffic Around Hwy. 101 Overpass

Continuing its efforts to combat traffic and reduce congestion, the Mill Valley City Council last week unanimously agreed to enter into an agreement with the County of Marin to study a practical solution to provide congestion reduction at the Highway 101 overpass connecting East Blithedale Avenue and Tiburon Boulevard. This agreement was recommended by a working group made up of Councilmember John McCauley and Vice-Mayor Stephanie Moulton-Peters and other elected officials and staff from the County of Marin, Tiburon, Belvedere, the Transportation Authority of Marin and Caltrans.

“I’m impressed with the progress,” Mayor Jessica Sloan said.  “Getting these key people together and identifying a realistic solution to our common problem is a significant achievement and difficult, creative work.” She thanked Councilmember McCauley and Vice Mayor Moulton-Peters who spearheaded the working group.

Traffic engineers report that an average of 80,000 cars move through the interchange each day. A small portion of the traffic (15 percent), comes from the Redwood Highway Frontage Road on the east side of Hwy. 101. It has been determined that those cars take one-third of traffic signal time to do so.

This imbalance impacts the function of the entire interchange – holding up drivers to get a small number of cars through the intersection, especially during peak periods. Improving the function of the corridor could open up additional green time for the dominant east-west traffic without diminishing other traffic flow.

“We have taken this on as a crisis approach,” said Councilman John McCauley. “Congestion reduction is the most important thing we have on our docket and we want to see this through.” McCauley said.

To develop solutions, Council authorized the City to partner with the other jurisdictions and to contribute up to $105,000 to develop a technical design study-- a Permit Engineering Evaluation Report (PEER)--which is expected to cost $350,000.

The Council believes that Mill Valley’s focus on congestion relief, together with committed partnership with other local governement entities and Caltrans, will yield practical solutions. 

“Determination and seed money creates progress and attracts other money,” Moulton-Peters said. “It’s a show of will and interest, and it’s been very well received by Caltrans.”

The County, which has jurisdiction over much of the land surrounding the interchange, has agreed to pay 50 percent of the study, or $175,000, while Belvedere is contributing $15,000. The Tiburon Town Council considers a proposed contribution of approximately $50,000 later this month.

The engineering report will examine widening a stretch of westbound Tiburon Blvd. between North Knoll Road and the Highway 101 overpass, and evaluate potential improvements at the Redwood Highway Frontage Road intersection on the east side of Hwy. 101.

The proposed improvements are designed to improve the function of the interchange while Caltrans moves toward a much larger comprehensive improvement of the overpass, a project with a multi-year timeline.

“This is the culmination of years and years of work on this issue,” Public Works Director Andrew Poster said. “We’re continuing to come up with solutions to address what has been one of the biggest bottlenecks in town.”

Go here for info on the City’s work to reduce traffic over the past two years.