The impact of ride-hailing companies like Uber and Lyft on transit ridership hasn’t been clear.  Anecdotes and personal hunch suggests that they’ve hurt transit ridership nationwide and increased driving miles.

Now we finally have a study to document that impact, courtesy of UC Davis’s Institute of Transportation Studies.  As the San Francisco Chronicle summarized:

•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.

This is an important step in understanding the cause of falling transit ridership.  It’s also an argument in favor of policy action, like congestion pricing and switching from the gas tax to a mileage fee to discourage extra car trips.

But fundamentally, transit agencies still need to do what they can to improve ridership, which includes requiring more development adjacent to transit stops and re-evaluating their fare structure and service network.