Rideshare behemoths Uber and Lyft purport to provide convenience for riders, but a new study drives home the point that these two companies in particular are burdening San Francisco with massive and broader inconveniences. Both rideshare firms refuse to disclose ride data publicly, but the San Francisco County Transportation Authority finds that Uber and Lyft drivers account for a full 15 to 20 percent of San Francisco weekday traffic.



The precise figure depends on which part of the assessment you choose to pick out. The Examiner declares it “15 percent of all vehicle trips in San Francisco”, the San Francisco Business Times pegs it at more than 20 percent. The reality depends on the time of day, which day of the week it is, and whether you’re counting overall traffic or aggregate vehicle trips. But the reality is also that Lyft and Uber are putting a ton of tread onto San Francisco streets.



“The perception that there are a tremendous number of [Uber and Lyft] vehicles out on the streets today is, in fact, true,” SFCTA deputy director Joe Castiglione told the Chronicle. “We see huge numbers of trips across all days of the week, primarily concentrated in the most congested parts of the city and at the most congested times of day.”



Mayor Ed Lee chimed in to CBS 5 that “There’s too many reports about double parking, picking up people in the wrong places, compromising bike paths and bike lanes.”



Well-heeled District 6 supervisor Jane Kim, who’s been looking to slap Lyft and Uber with a small per-ride tax, was quick to comment on the report. “Ride-sharing companies are logging more than a half million vehicle miles on our streets every day. This is having an effect on our quality of life as well as creating serious public safety concerns  no one wants the ambulance that might save their life to be stuck in a traffic jam,” Kim said in a release.



The report found that the largest concentration of rideshare cars are found downtown, in South of Market, the Mission, Pacific Heights and the Marina neighborhoods. During rush hours, defined as 6-9 a.m. and 3:30-6:30 p.m. on weekdays, rideshare trips account for nearly a quarter of all trips taken downtown and in SoMa.



The report also found some upside in Uber and Lyft. They’re far better than taxicabs at covering the western neighborhoods of San Francisco like the Sunset and the Richmond. Conversely, though, rideshares provide far fewer trips to lower income neighborhoods like the Bayview and Excelsior.



One could argue in response that this is all just traffic that would otherwise exist anyway, with Lyft and Uber driving rather than the riders themselves. But isn’t some of this traffic just riders killing time between fares? We can only speculate. But if Lyft and Uber won’t hand over their ride data, it’s kind of incumbent on the community to speculate on the rideshares’ effects.



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