Such individuals may be walking more and may live in neighborhoods with dangerous streets and inadequate infrastructure. In San Francisco, 77 percent of severe and fatal injuries to people walking occur on only 13 percent of the city’s streets, according to a 2015 report, updated in 2017, that maps high-injury corridors.
Unlike most previous research, San Francisco’s Vision Zero High Injury Network study integrated hospital reports with police data. Because patients undergo a full medical analysis, hospital data are more accurate in revealing the extent of injuries than are police reports.
The new methodology also reveals higher numbers of injuries to bicyclists and people of color, who are less likely to go to the police, said Megan Wier, the director of the city’s Program on Health, Equity, and Sustainability and co-chair of the San Francisco Citywide Vision Zero Task Force.
The review showed, for instance, that the Tenderloin community, with a high concentration of both children and seniors, sees more traffic deaths and injuries, as do majority black neighborhoods, such as Bayview and Hunters Point.
Two important lessons of the new methodology are to use data wisely and to integrate departments, Wier told me. A systematic analysis of existing injury patterns is vital. It begins by mining data that already exists but may be underutilized.
“Any jurisdiction with massed data, start where you’re at with respect to what data you have access to, analyze it, and then work to address the gaps moving forward,” she said.
The study began separately from San Francisco’s 2014 Vision Zero plan, but was immediately integrated into the bold attempt to reduce traffic deaths. The Vision Zero initiative correlates with the lowest number of traffic deaths in the hundred years since the city started counting them, a number achieved in 2015, with the second lowest in 2017. This is amazing considering how few cars there were in the early Twentieth Century and that pedestrian deaths are rising across the country.
To help where it’s most needed, the city’s Vision Zero Action Strategy mandates that “historic injury inequities in vulnerable communities are addressed.” Disturbingly, “half of all severe and fatal injuries occur” in “areas with high concentrations of low-income residents, immigrants, and non-English speaking residents and seniors.” Furthermore, seniors constitute half of pedestrians killed by cars, but only 15 percent of city residents.
San Francisco’s success is partly due to its high injury network studies, allowing it to focus on those neighborhoods most in need. Because many residents do not come out for traditional planning meetings, officials must find new ways to go to residents, such as pop-up meetings, Wier explained. In the Tenderloin, for instance, it is important to have speakers of languages shared by many residents, such as Mandarin and Spanish.
The city’s Vision Zero strategy notably calls for reducing vehicle miles traveled, as fewer cars mean fewer deaths and injuries. This means that Vision Zero integrates with sustainable transportation strategies such as better transit, more walkability and bikeability, and transportation demand management.
Other strategies to reduce traffic deaths and injuries include slowing traffic to 25 mph or less on the most dangerous streets, Wier said. A combination of separated bike lanes and narrowed streets further slows cars and enhances safety. Automated traffic enforcement is also a big part of San Francisco’s Vision Zero plan. And educating drivers to be aware of people walking and biking is critical.
Mapping high fatality corridors by integrating data from police and medical records is a necessary step to achieving Vision Zero and helping the most vulnerable communities.
Graphic from the San Francisco Department of Public Health.