Next Tuesday, the SFMTA Board of Directors will vote on whether to alter the already-passed Valencia Bike Lane project design by implementing three left turns on Mid-Valencia, at 17th Street, 21st Street and 23rd Street.
This proposal comes at the direction of the Mayor’s office, after much pressure from merchants who believe reinstating left turns will improve traffic flow and congestion on Valencia. However, safe street advocates know this will make congestion worse and make Valencia less safe.
Citywide, left turns account for 40% of pedestrian traffic fatalities, according to SF’s Vision Zero data. Even though they are currently not allowed on Valencia, data shows that left turns already are a source of danger: illegal left turns are the number one cause of crashes along the corridor since the installation of the center-running bike lane. We are concerned that allowing left-turns inconsistently along the corridor will create more confusion, and therefore danger, for all users of the road.
To minimize the safety concerns left turns introduce, SFMTA traffic engineers are proposing three traffic light cycles per intersection.
- Northbound lane has the green light and can make left turns while the southbound traffic lane and pedestrian light are red.
- Southbound lane has the green light and can make left turns while the northbound traffic lane and pedestrian light are red.
- East-west cross streets have the green light while both Valencia lanes are red.
While this approach will certainly curb the danger left turns create for people who bike and walk, a three-phased light cycle at each of these intersections will significantly slow down traffic on the corridor and will not achieve the merchants’ desired outcome.
Lastly, as a best practice, SFMTA staff frequently say it takes 90 days to normalize behavior change, and the most useful evaluation data is after that three-month window. Adding left turns within that 90-day window, while road users are still adjusting their behavior to the new lane design, will muddy evaluation data and further increase potential confusion, endangering vulnerable road users even further. Equally concerning is that, without clear data delineating results for the new street design before left turns are introduced and after, any increased traffic congestion caused by reintroducing left turns will be blamed on the bike lane design, rather than the real culprit.
Left turns are not part of the Mid-Valencia design that was approved by the SFMTA Board of Directors last year in November. In order to implement them, the SFMTA Board must approve them as a separate item next Tuesday.
Your San Francisco Bicycle Coalition will be showing up to oppose the implementation of left turns on Valencia. RSVP below to join us to give public comment — your voice matters.
