Tiburon council receives preliminary data from traffic study

Tiburon Boulevard’s afternoon traffic is largely caused by solo drivers, according to a town consultant.

The Parametrix firm updated the Town Council on Wednesday about its preliminary findings in a traffic and infrastructure study. The council awarded the company a contract in June for up to $360,000 to conduct the study.

The final report, expected next year, will have a list of improvements to make over five years to reduce congestion, as well as ideas to consider over the next 20 years.

“The outcome, at the end of the day, is really a blueprint for a transportation and infrastructure action plan that is going to recommend things that can be done as soon as possible as well as longer-range ideas,” consultant David Parisi said.

The consultants began studying traffic and transportation infrastructure along Tiburon Boulevard over the summer. The study area included four schools, eight intersections, bus stops and pedestrian infrastructure along the route. It included other key areas such as Paradise Drive and Trestle Glen Boulevard.

Single-occupant vehicles on the boulevard make up 65% of the traffic, the preliminary study found. Multi-occupant vehicles accounted for 18%; school vehicles, 4%; contractor vehicles, 10%; and commercial vehicles, 2%. It also found that 27% of trips were less than 4 miles.

Jen Shriber, a planner with Parametrix, said weekday traffic peaked from 8 to 9 a.m. and 3 to 4 p.m. The majority of vehicles — an average of 2,083 in the morning and 2,141 in the afternoon — traveled east of Blackfield Drive. West of Avenida Miraflores, there were an average of 1,682 vehicles in the morning and 1,667 in the afternoon. The firm counted an average of 770 vehicles traveling east of Lyford Drive in the morning and 857 in the afternoon.

“But these trips are not all residents, there could be people coming in from out of town, from different areas for work for service trips, for contracting trips as well,” Parisi said.

The peak-hour traffic data was collected manually over two weeks. Compared to the last counts, done in 2012, traffic volume has decreased in those areas by 4%, 10% and 25%, Shriber said.

Over 24 hours, 63% of trips were made by private automobiles; 1% were public transit; 1% were rideshares; 33% were people walking; and 3% were cyclists.

Councilmember Isaac Nikfar asked to add three “problematic” intersections — Reed Ranch Road, Upper Cecilia Road and Gilmartin Drive — to the study. He asked that the consultant’s next update included a list of clearly stated “measurable” goals.

“For instance if there are 2,000 cars per hour, and it takes them X time now, what are we solving for?” Nikfar asked. “I think it’s going to be a really important part of this and I’d like that in the next version of this.”

Parisi said they will begin brainstorming potential improvements — traffic signals and controls, new lanes, road widening, transit upgrades and possible school area routes — that could be compiled into a list of recommendations.

Mayor Alice Fredericks and parks commissioner Timothy Burr will represent Tiburon on the study’s advisory committee. Other members include representatives from Caltrans, the Transportation Authority of Marin and Belvedere.

A community workshop is planned on Dec. 3. A final draft is expected around June.