Aaron Thornton was walking north on Valencia Street when a white van turned left onto Duboce Avenue, nearly striking the 41-year-old as he crossed the street. Thornton threw his hands up as he shouted to the driver, then took off running, hoping to catch the vehicle.
“I almost got him after he almost got me,” said Thornton, who works two blocks away from the intersection where the close call took place. “I usually don’t chase after cars, but this was close,” he said, still out of breath after the incident.
Thornton’s near-collision isn’t unique. Duboce Avenue and Valencia Street ranks fifth on the list of the city’s most dangerous intersections, according to the 2010-2011 San Francisco Collisions Report from the San Francisco Municipal Transportation Agency.
Five of the city’s seven worst injury-collision intersections lie on the northern edge of the Mission District, where U.S. Highway 101 North funnels cars onto the streets of San Francisco. The report, covering incidents from 2009 to 2011, was released last month.
Overall, a total of 3,111 injury collisions, including 28 fatalities, occurred in San Francisco in 2011. After falling during the 1990s,both injury crashes and fatal crashes have remained stable since 2004.
But car-bike crashes rose to a 10-year high last year, as soaring bicycle ridership alters the dynamics of San Francisco’s traffic, challenging the city to find safer ways for cyclists and motorists to coexist on city streets.
The city is trying to lessen the danger at high-collision sites citywide, particularly in the northern end of the Mission District where Mission Street, Otis Street and 13th Street all converge, according to SFMTA spokesman Paul Rose.
“This intersection was reviewed in 2011 by SFMTA and signal timing was changed in November of 2011, which could reduce the number of collisions at that location,” said Rose in an email to Mission Local.
SFMTA also changed pedestrian crossing times, coordinated signal timings with adjacent intersections and modified the all-red signal clearance phase — the time period when all signal lights at an intersection are red to allow for the intersections to clear — Rose said.
Citywide, Rose said, SFMTA is installing new pedestrian safety signs and pedestrian countdown signals, improving crosswalk markings and signal timing changes to aid pedestrian crossings.
The riskiest intersections around the Mission are: Market Street and Octavia Boulevard, with 30 incidents reported; 13th Street and Mission/Otis Street, with 19; and Duboce Street and Valencia, with 18.
The intersection of 13th Street and South Van Ness Avenue had 18 reported injury collisions, while 16th Street and Potrero Avenue had 16.
“If I don’t hear honking or yelling it’s an odd day,” said John Carr, 19, at the northwest corner of Duboce Avenue and Valencia Street, where he works as a mechanic. “People don’t know how to merge, they get nervous,” he said of the intersection.
Injury collisions involving bicycles have been rising, according to the SFMTA report, with 630 incidents in 2011, 5 percent more than the prior year and the highest recorded number in the last decade. Automobile-bicycle crashes accounted for a fifth of all injury collisions in San Francisco.
The rise is due mainly to the increasing popularity of cycling, which has surged 71 percent in the last five years, according to SFMTA.
In addition to increased bicycle ridership, the rise may reflect improved recording of bike crashes by the police department, said Kit Hodge, deputy director of the San Francisco Bicycle Coalition.
“For the past few years,” Hodge said, “the SF Bicycle Coalition has worked to educate officers about the importance of taking reports for bicycle-related crashes, and educated both officers and the public about official SFPD policy, which requires they take a report at the request of the bicycle rider, whether or not they get into an ambulance.”
Responsibility for collisions “seems to be evenly split among bicycle riders and motorists,” the SFMTA report stated. The most common fault of cyclists was unsafe speed, accounting for 16 percent of crashes. For motorists, the problem was failure to signal a turn, which caused 8 percent of collisions.
Of the 28 fatal collisions reported in 2011, three involved bicycle riders. The most perilous intersections for car-bike crashes were Market and Valencia and Duboce and Valencia, the report added.
SFMTA made bicycle lane striping changes on Market Street at Valencia in 2011 “to reduce the likelihood of Market Street right-turn hook collisions,” according to the report.
Cycling advocate Hodge said, “The city will be redoing the Market and Valencia intersection later this year to make it safer to turn left from Market to Valencia on your bike.”
Camera installations might create safer streets leading to Hwy. 101, according to the cycling coalition. “We have been working for a long time to get the state and city to install camera enforcement at Market and Octavia to deter people from making illegal right turns onto the freeway,” said Hodge.
Despite challenges posed by increasing ridership, Hodge says it’s an exciting time for him and for the bicycle coalition.
City streets are “getting safer with new improvements like separated bike lanes,” he said. “We are especially excited to see so many families and seniors now using a bike, especially in the Mission.”