City of Mill Valley Adjusts Traffic Signal Timing, Convinces Caltrans to Do the Same

On the heels of consecutive weekends of major traffic backups along East Blithedale Avenue, the City of Mill Valley has made additional changes to the timing of its six traffic lights from the Camino Alto and Miller Avenue intersection out to East Blithedale Avenue, Tiburon Boulevard and Highway 101. 

The City has also successfully lobbied Caltrans, which controls the traffic signals on East Blithedale Avenue/Tiburon Boulevard Tower/Kipling Drives, at the southbound on-ramp of Hwy. 101 and at the Hwy. 101 northbound on-ramp, to make changes to the timing of those lights in an effort to synchronize with the City’s traffic signals. Caltrans made those changes on Tuesday, May 20. 

Caltrans’ changes are expected to reduce the heavy traffic backups that residents and visitors have experienced in recent weekends, according to Public Works Director Jill Barnes. In the case of all nine traffic signals, the drivers along the Camino Alto and East Blithedale corridors will now experience longer green light times, helping move traffic along those corridors more quickly, Barnes said. 

“We’re trying to do something for the greater good of all drivers in town,” Barnes said. “Once drivers turn onto those corridors, they will move more quickly through them.” 

The changes come on the heels of the May 5 fine-tuning of Mill Valley’s traffic signals. City officials closely monitored the impact of those changes, and decided to lengthen the green light times along Camino Alto and East Blithedale, Barnes said. 

But a more significant obstacle was getting those lights to synchronize with Caltrans’ three traffic lights near and on the Hwy. 101 overpass. The green light times at Caltrans’ lights were significantly shorter, meaning that while Mill Valley’s lights were sending traffic along those corridors through more quickly, an even larger than usual backlog was occurring once traffic reached Caltrans’ traffic lights. The backups stretched back as far as Park School. 

Barnes said that while traffic worsened over the previous two weekends, the traffic light timing changes made on May 5 have improved traffic flow along Camino Alto and East Blithedale on weekdays. Barnes also noted an additional change that has been made since May 5: to allow pedestrians and bicyclists to more safely cross East Blithedale, the crossing times at some intersections, including East Blithedale at Lomita Drive and Roque Moraes, has been lengthened. 

“That is strictly a safety issue,” Barnes said. 

City officials have noted that at the same time that City and Caltrans staff have been working on the signal timing at key intersections, a number of recent accidents and incidents have caused significant back-ups. Since the beginning of May, motorists have experienced a few signal outages outside of City limits caused by power interruptions, some repair projects, traffic collisions, and yesterday’s unusual incident of a load of nails being spilled on Hwy. 101, causing the California Highway Patrol to close the northbound onramp to the highway. These incidents highlight the limited capacity of Mill Valley roads and how quickly interruptions such as these can wreak havoc with traffic movements. 

For City of Mill Valley officials, reducing traffic backups is a major priority, and the City appreciates the patience of residents, business owners and visitors during this difficult time.