Uber and Lyft account for 15 percent of all vehicle trips inside San Francisco, according to a new report, and the majority of the trips occur in neighborhoods that already enjoy the most public transit options.
The San Francisco County Transportation Authority collected San Francisco traffic data on Uber and Lyft in conjunction with Northeastern University from Nov. 12 to Dec. 20, 2016, which the agency published Tuesday, in a first-of-its-kind report on ride-hails in The City.
The report doesn’t draw conclusions about ride-hail impacts on traffic, but the data is intended to help lawmakers address a key question: Do Uber and Lyft worsen San Francisco’s traffic woes?
The data has nudged local officials closer than ever before to affirming that question. Perhaps most revealing in the data is that Uber and Lyft vehicles travel mainly in neighborhoods that already see the most traffic congestion during peak traffic times, according to transit officials.
These neighborhoods — Downtown, South of Market, the Marina and the Mission — already enjoy the most public transit options in The City, officials said.
Notably, Uber and Lyft have guarded their traffic data vigorously, even legally, and its regulator, the California Public Utilities Commission, has kept it under lock and key — though that may change.
The SFCTA and Northeastern obtained the data by scraping publicly “exposed” data from Uber and Lyft drivers, including a vehicle identifier with time-stamped coordinates sent in a datastream. Northeastern University researchers sent a “ping” for that data every five seconds for six weeks, according to the report.
The data accounted for drivers who drive for both Uber and Lyft, and was limited to showing where drivers accepted a ride, not where they picked up a passenger — but city officials said the data is still revealing.
The report found that nearly 5,700 Uber and Lyft vehicles roam San Francisco streets at peak traffic times, especially between 6:30 and 7 p.m., and on Fridays there are over 6,500 Uber and Lyft vehicles on the street from 7:30 to 8 p.m.
That’s data San Francisco hasn’t seen, though San Francisco Treasury Office data show there are 45,000 active Uber and Lyft drivers who drive in San Francisco as of 2016.
“Shocking news: It confirms everything that you see [that has San Franciscans] extremely frustrated,” said Supervisor Aaron Peskin, who is also the chair of the transportation authority’s board.
Joe Castiglione, a transportation authority planner, cautioned that the study itself does not definitively demonstrate Uber or Lyft contributing to traffic, but instead reveals data that is key for policymakers to have on hand when addressing that question.
Most weekdays, Uber and Lyft vehicles make about 170,000 vehicle trips in The City, according to the transportation authority, which is 12 times the number of taxi trips — and 15 percent of all vehicle trips, total, that begin and end in San Francisco.
While ride-hails account for 15 percent of daily trips within San Francisco, only 1 percent of vehicles are from public transit, 1 percent are taxis and 83 percent are private autos.
Those trips constitute 20 percent of all miles driven in San Francisco each day, a startling 570,000 miles traveled by vehicles starting and ending in San Francisco, according to the report.
Uber and Lyft trips are concentrated on the busiest major streets, the report found, but also within neighborhoods themselves along already existing public transit lines.
Notably, this data is all conservative, Castiglione said, as it measures only trips that start and end in San Francisco. Trips to and from San Francisco International Airport, or to and from the South Bay or East Bay and San Francisco, are not included in the data.
Still, “the perception that there are tremendous amounts of vehicles on the street [is], in fact, true,” Castiglione said.
Some data perhaps flattering to Uber and Lyft was revealed by the report, including maps showing that Uber and Lyft provide better coverage to more sparsely populated southern and western neighborhoods than taxi cabs.
However, the number of trips in the western and southern neighborhoods was far lower than in the urban core, even when accounting for downtown’s higher population density, the report noted.
Uber and Lyft picks up passengers “precisely where we don’t want vehicles” from a standpoint of mitigating congestion, Castiglione said.
The report also found those drivers come from far-flung cities to drive in San Francisco.
Data obtained from the Treasurer’s Office showed most drivers come from San Francisco County, at 29 percent, followed by Alameda County with 21 percent of all San Francisco ride-hail drivers. Nearly 16 percent of all drivers came from San Mateo County, 12 percent from Contra Costa County and 10 percent from outside the Bay Area.
Click here to read the full report from the San Francisco County Transportation Authority.