Collisions decline on ‘slow streets,’ but speedier traffic prompts fresh calming measures

San Francisco transit officials say they will need to work on adding measures to slow down vehicles on streets designated as a “slow street.”

The San Francisco Municipal Transportation Agency last week released an evaluation report on its Slow Streets Program, which became a permanent program last December when the agency boards initially approved 16 permanent slow streets.

As part of the permanent program, directors required the program to meet specific targets, including that the average vehicle speed be 15 miles per hour, and that the average daily volume of vehicles be 1,000 or less. Only four slow streets meet the vehicle speed target, the report said: 23rd Avenue, Minnesota Street, Sanchez Street and Shotwell Street.

The fastest slow streets are Hearst Street at 20 mph followed by Arlington Street at 19 mph. Cabrillo Street and 20th Street are tied for third at 18 mph.

In addition, the report said “egregious” speeding – vehicles traveling over 30 mph – has been observed on all 16 slow streets.

SFMTA Streets Director Tom Maguire said last week that staff will be proposing changes on slow streets that are meeting program targets:

“We’ll be proposing changes on those streets to make sure we eventually meet the targets that we’ve set. Volume management tools like traffic diversions and turn restrictions and speed reduction tools like traffic calming and speed humps, we’re working on that throughout the summer.”

The report did have some good news. Collisions on slow streets saw a 48 percent decrease in collisions throughout the entire network of slow streets, Maguire said. He added that 12 of 16 slow streets are meeting the average vehicle volume target.

Maguire told the board that he hopes to complete the adjustments needed to meet the program’s targeted goals by the end of summer and to collect data through the fall with a report back to the board by the end of the year.

Since the initial adoption of the permanent slow streets program, directors approved two more streets for slow street designation — Page Street and 20th Street.

On the SFMTA’s website, directors will decide at its May 16 meeting on whether to include Chenery Street and Lapu-Lapu, Rizal, Tandang Sora, Bonifacio and Mabini streets as part of the permanent program.