Uber, Lyft reduce transit use, increase vehicle miles, report says

FILE - In this Tuesday, Jan. 12, 2016, file photo, a driver displaying Lyft and Uber stickers on his front windshield drops off a customer in downtown Los Angeles. When management upheaval, allegations of corporate espionage, and revelations of sexual harassment sent Uber into a public relations sinkhole, its long overshadowed rival Lyft shifted into overdrive. The company seized the opportunity to recruit disillusioned drivers so it could be more responsive to passengers searching for a ride-hailing alternative to Uber. (AP Photo/Richard Vogel, File) less FILE - In this Tuesday, Jan. 12, 2016, file photo, a driver displaying Lyft and Uber stickers on his front windshield drops off a customer in downtown Los Angeles. When management upheaval, allegations of ... more Photo: Richard Vogel, Associated Press Photo: Richard Vogel, Associated Press Image 1 of / 1 Caption Close Uber, Lyft reduce transit use, increase vehicle miles, report says 1 / 1 Back to Gallery

As ride-hailing has exploded in popularity, it’s caused a slight decrease in car ownership — but has also reduced use of public transit, biking and walking. The result is a likely increase in both traffic and the number of miles traveled in a vehicle, according to a national study of ride-hailing adoption from the UC Davis Institute of Transportation Studies being released Wednesday.

“Although we found that ride-hailing can be complementary to transit and reduce vehicle ownership for a small portion of individuals, we found that (overall) these services currently facilitate a shift away from more sustainable modes towards low occupancy vehicles in major cities,” said Regina Clewlow, lead author of the report, in a statement.

The UC Davis study was based on a representative panel of consumers in seven major U.S. metropolitan areas. Among other findings:

•Urban Americans use ride-hailing much more than those in the suburbs. While 29 percent of city dwellers surveyed use Uber and Lyft, only 7 percent of suburban respondents do so in their hometown. Another 7 percent of suburbanites use the services when they travel elsewhere.

•Almost a quarter (24 percent) of ride-hailing passengers use the services daily or weekly.

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•Parking is passengers’ top motivation for hopping into an Uber or Lyft rather than driving, with 37 percent citing this. Avoiding drinking and driving was cited by 33 percent.

•Usage is more prevalent among younger people. Among those 18 to 29, some 36 percent use ride-hailing compared with only 4 percent among those age 65 and older.

•The vast majority (91 percent) of ride-hailing customers say it has not changed whether or not they own a vehicle.

•Riders who now drive less often said they instead use ride-hailing for those trips. The report said it wasn’t possible to determine changes in net vehicle miles traveled.

•Urban ride-hailing passengers decreased their use of public transit by 6 percent. Bus and light rail service were both used less often by Uber and Lyft riders, while commuter rail saw a 3 percent bump in usage.

•Many ride-hailed trips (49 to 61 percent) would have not been made or would have occurred via walking, biking or transit.

“Ride-hailing is currently likely to contribute to growth in vehicle miles traveled in the major cities represented in this study,” the report authors wrote.

Given that likelihood, policymakers should consider giving priority to high-occupancy vehicles through methods such as congestion pricing and priority lanes, the report said.

While Uber and Lyft have extensive data on their customers, both have been reluctant to share it. That has forced lawmakers and researchers to seek other ways of discerning the services’ impacts. San Francisco has gone to court in a pending case to demand information from the companies about their use of city streets. The city also commissioned its own study about Uber’s and Lyft’s impacts on congestion, in which an outside researcher used software to query the companies’ apps every five seconds over a six-week period.

Carolyn Said is a San Francisco Chronicle staff writer. Email: csaid@sfchronicle.com Twitter: @csaid