Ridesharing Might Increase Traffic, But Public Transit is Failing, Anyway

Nobody knows whether ridesharing services increase traffic, decrease it, or have no effect. It is likely all three scenarios are possible, depending on geography. In parts of the country that are relatively dense, with highly developed public transportation, ridesharing might increase traffic, if it shifts ridership from public transportation.

This is a relevant trend for mobile service providers since such networks are expected to play a growing role supporting autonomous vehicles that might replace much of the human-driven ridesharing supply.

Some now argue that ridesharing services increase traffic. Others will point out that passengers are shifting away from use of public transportation is falling anyway, for obvious reasons: jobs and the places people live are more scattered than in the past.

In many U.S. cities, buses and light rail simply are not flexible and convenient enough to move people where they need to go.

That is why ridership of public transit has been falling. U.S. transit ridership in March 2018 was 5.9 percent below March 2017, according to the latest data published by the Federal Transit Administration.

In fact, use of public transif seems to have been falling for three years.

Ridership declined in all of the nation’s 38 largest urban areas (and the 39th, Providence, gained only 0.1 percent new riders). Transit systems in Austin, Boston, Charlotte, Cleveland, Miami, Milwaukee, Philadelphia, San Diego, and Tampa-St. Petersburg all suffered double-digit declines, with Austin losing 19.5 percent and Charlotte 15.4 percent despite being two of the fastest growing urban areas in the nation.

The problem seems to be that “big box” transportation does not work as well, anymore, since jobs now are more dispersed, in most cities. That is one reason some believe more flexible, smaller capacity solutions might work better.

And yes, with enough land use planning to densify urban cores one can concentrate work, but at the cost of creating unaffordable housing close to work. There is no painless solution.

One study estimates 70 percent of Uber and Lyft trips are in nine large, densely-populated metropolitan areas (Boston, Chicago, Los Angeles, Miami, New York, Philadelphia, San Francisco, Seattle and Washington DC.

Other studies reach opposite conclusions, arguing that ride sharing services can reduce traffic. One MIT study suggests multiple passengers per vehicle would have a clear effect on traffic.

  

Referred to as transportation network companies, such TNCs account for 90 percent of TNC or taxi trips in eight of the nine large, densely-populated metro areas (New York is the exception) and in other census tracts with urban population densities, the study estimates.

In suburban and rural areas, taxis serve slightly more riders than TNCs. The same is true in New York City (counting car services in the taxi category).

People with disabilities make twice as many TNC/taxi trips as non-disabled persons, but taxis account for two thirds of their TNC or taxi trips.

TNCs compete mainly with public transportation, walking and biking. About 60 percent of TNC users in large, dense cities would have taken public transportation, walked, biked or not made the trip if TNCs had not been available for the trip.

About 40 percent would have used a personal vehicle or a taxicab had TNCs not been available for the trip.

The bottom line, one study claims, is that  shared ride services such as UberPOOL, Uber Express POOL and Lyft Shared Rides, while touted as reducing traffic, in fact add mileage to city streets, at least in bigger urban areas.

Private ride TNC services (UberX, Lyft) put 2.8 new TNC vehicle miles on the road for each mile of personal driving removed, for an overall 180 percent increase in driving on city streets.

Inclusion of shared services (UberPOOL, Lyft Line) results in marginally lower mileage increases – 2.6 new TNC miles for each mile in personal autos taken off the road.

Shared rides add to traffic because most users switch from non-auto modes. But that is happening with public transportation in any case.