Uber and Lyft are putting a dent in mass transit

All those Uber and Lyft cars around major cities are cutting into bus and light rail ridership, according to a new study. But as for how many cars these services are taking off the road, that’s still a question mark.

The introduction of ride-hailing caused a 6 percent net reduction in public transit use in cities, UC Davis researchers found in a nationwide survey carried out in two phases between September 2014 and January 2016. Ride-hailing caused a 6 percent reduction in bus services and 3 percent in light rail, but had a positive, complementary effect on commuter rail services, increasing their usage by 3 percent.

While much of Uber and Lyft’s early regulatory battles were fighting rules that traditionally applied to taxis, the companies have begun pitching innovations like carpooling and self-driving vehicles as technologies that could augment mass transit.

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“Mass transit is an important part of the solution, but not the silver bullet,” former Uber CEO Travis Kalanick wrote in a 2016 Wall Street Journal op-ed. “New York has one of the best public transportation systems in the world, but more than 2 million cars drive through New York City every day, because the subway will never reach everyone’s front door.”

Both Uber and Lyft have already signed significant U.S. partnerships with transit providers and local governments to provide “first mile” and “last mile” services, meaning rides to and from public transit stations. Uber has inked deals with a rural town in Ontario and a New Jersey suburb to provide rides from a trans station because it didn’t have enough parking spaces, and Lyft recently announced a partnership with Amtrak.

Whether such deals are effective “depends on the type of city, and we need to consider as a society what these services do [and] how we want to design our cities around how we move in them,” said Regina Clewlow, who co-authored the study with Gouri Shankar Mishra, out of UC Davis’ Institute of Transportation Studies. Clewlow previously worked for Daimler (an Uber competitor), and Mishra currently works for Amazon. The full study is embedded at the bottom of this article.

Clewlow says Uber and Lyft can have a positive impact when they are providing services that get people to ride in fewer cars alone — via carpooling options like UberPool and Lyft Line. But there isn’t much publicly available data about such a distinction, and the effects vary widely between different cities and suburbs.

“There are a lot of cities in the U.S. that are predominantly suburban, and the only way to get around is by driving,” Clewlow said. “If ride-hailing can be productive in those environments, it can provide more benefit.”

When reached for comment, spokespersons from Uber and Lyft provided VICE News with statements, and pointed to research with findings contrary to the UC Davis report.

“We, along with global experts on this issue, believe that the future of urban transportation is going to be a mix of public transportation and ride-sharing,” the Uber statement said. “That’s why we’re partnering with public agencies around the world to deliver on this vision of the future.”

“Since Day One, Lyft has been focused on increasing occupancy in cars on the road,” the Lyft statement added. “Seventy-six percent of Americans drive alone to work, and traffic congestion continues to drag down economic productivity and quality of life.”

You can read the full study here.