Shelter-in-Place order allows SFMTA to analyze sources of delays

While San Francisco has been under its shelter-in-place order, traffic has virtually disappeared along with transit service delays.

These unusual circumstances have allowed the San Francisco Municipal Transportation Agency (SFMTA) to analyze data for Muni travel times and key sources of delay in ways that would otherwise be impossible. By monitoring Muni travel times during shelter-in-place, SFMTA was able to quantify the impacts congestion has on Muni service during normal times. What the agency is learning can help bring back the transit system in a way that addresses past problems, as the city begins to recover. 

With fewer cars on the road, peak Muni travel times were reduced citywide by an average of 15 percent compared to pre-COVID-19. Most travel time savings came from reduced traffic delay, with less than 5 percent coming from fewer people getting on and off the bus. Specific transit corridors saw much higher time savings. For instance, the 28 19th Avenue line experienced some of the most dramatic travel time reductions, with peak time savings of up to nearly 50 percent in some areas. But many heavily traveled Muni corridors throughout the city saw significant travel time reductions, as well. This data underscores that much of Muni’s delay and reliability issues are caused when buses are stuck in traffic congestion.

Map of San Francisco showing Muni travel time savings on corridors throughout the city.

Perhaps most notably, corridors with existing transit lanes had very different results. During shelter-in-place, most bus lines traveling in transit lanes saw little change in travel times because those lanes already allow Muni to avoid traffic congestion. This data tells the success story of the Muni Forward program, where SFMTA has made targeted investments in transit priority, and is seeing results.

As Muni continues to provide service for essential trips during this crisis, the importance of saving time on routes is more critical than ever. Physical distancing requirements mean that Muni’s passenger capacity is cut in half from pre-COVID levels. With Muni buses at reduced capacity, there is a higher risk of crowding at stops and on buses as people wait for a bus that has room. Faster travel times mean buses can complete trips in less time and turn around back into service more quickly, increasing frequency with the same number of buses. This increased frequency allows Muni to serve more people to address crowding and maintain better physical distancing on buses. In addition, shorter travel time means passengers spend less time on the bus, reducing their risk of exposure.

As the local economy restarts, San Francisco has an unprecedented opportunity to purposefully rebuild its transportation system to facilitate a resilient recovery. Public transit is at the foundation of San Francisco's economy, connecting workers to their jobs. Congestion is expected to return quickly, likely above pre-COVID levels, after stay-home-orders are lifted and more businesses reopen. While traffic delay is a burden for all road users, it affects transit riders the most right now because it increases the risk of exposure to COVID-19 by elongating trips. SFMTA is working deliberately to update the Muni network to support the city’s new normal and address transportation needs that have been amplified by the health crisis.