skip to main content

→ Top Stories:
Clean Power plan
Safe Chemicals

Lucian Go’s Blog

Dynamic Ridesharing: Turning Empty Seats Into Affordable Transportation

Lucian Go

Posted December 21, 2012

, , , , , , , , ,
Share | | |

With much of New York City’s public transit system crippled by flooding and debris due to Superstorm Sandy this past October, Mayor Bloomberg mandated high-occupancy vehicle (HOV 3) lanes on most bridges and tunnels going into Manhattan, recognizing that operational buses and single-occupancy vehicles would be insufficient to transport some 500,000 commuters to work. For two days, many people left their cars at home and began to line up at entrances to bridges and tunnels to catch rides into Manhattan. Essentially, New York City put an emergency ridesharing program in place to cope with the loss of public transit.

New York City’s emergency HOV 3 mandate brings up an interesting question: will it take nothing short of a natural disaster to jumpstart ridesharing programs and harness the wasted mobility inherent in solo commuting, which the U.S. Census estimates to be around 76 percent of automobile commuters? If recent studies are any indication, the answer might be no. Recent trends in transportation and technology use point to ridesharing (particularly dynamic ridesharing programs that match users in real time) as a transportation alternative with significant potential for widespread growth and environmental benefits. The popularity of these programs has garnered the state’s attention, with the California Public Utilities Commission‘s (CPUC) decision yesterday to become the first regulatory body in the country to formally evaluate these services.

Grand Street: Texting

The first major trend that may help these programs gain traction is that fewer Americans are commuting alone—a trend that seems to coincide with an overall decrease in vehicle miles travelled (VMT). In 2009, for the first time in the forty years that the National Household Travel Survey began collecting travel data, VMT had declined among all age groups. Baby Boomers, the generation that has largely been intertwined with the rise of the automobile, are now reaching the age where retirement and empty nests spell less driving.

The age group whose driving has declined the most is the same one that is most likely to adopt technology-based alternatives like dynamic ridesharing: my generation, the “Millennials”, generally defined as being between the ages of 16 and 34. This age group’s average annual VMT dropped by 23 percent between 2001 and 2009, according to an April study by the Frontier Group. The study shows that this shift away from driving isn’t confined to cash-strapped twenty-somethings; even Millennial households making over $70,000 a year have doubled their use of transit while increasing bike trips by 122 percent. A Zipcar/KRC study found that nearly half of Millennials say they drive less to protect the environment--more than any other age group.

This generation’s changing preferences on a wide range of issues beyond driving indicate that they are increasingly driving less not because they can’t, but because they don’t want to. And it isn’t just confined to driving; it may come as a shock to some that nearly half of young people ages 18 to 24 would choose access to the internet over access to a car, according a study cited in the New York Times last year. By comparison, only 15% of Baby Boomers would choose the internet. In a generation where social networking is the norm and where phone calls and face-to-face conversations are largely reserved for relatives and significant others (at least among the most avid texters), not having internet access might not feel much different than being under house arrest.

One analyst called the iPhone the “Ford Mustang of today”- the new American symbol of independence and adulthood. The article suggests that while a car provides physical mobility, it doesn’t provide the kind of connectedness that it used to, while the responsibilities of car ownership are becoming too big a burden for a generation of people that are moving around more and settling down later

As a result, the innovative ridesharing programs that are emerging may fit the needs of many people better than personal car ownership does. Zimride is a San-Francisco-based ridesharing service built around university and corporate networks, and its UC Santa Cruz community is a good example of the potency of this service. In three and a half years, it has grown to over 7,000 registered members—nearly forty percent of the university’s combined student and faculty population- saving an estimated 820,000 miles of driving, according to the company.  In May, Zimride’s founders launched Lyft, a donation-based dynamic ridesharing service that matches riders and drivers in real time, with safety measures including background checks, insurance, user reviews, and social media connectivity. Drivers are identifiable through the distinctive fuzzy pink mustaches they mount on the fronts of their cars. As a cheap and convenient alternative, Lyft has become a hit in the Bay Area, with 80% of users becoming repeat customers. Zimride and Lyft are not alone, as numerous services are operating at local, regional and even international levels; Sidecar is expanding its presence on the West Coast, having recently raised $10 million in funding, and Avego has pilots operating around the world and has offices in the U.S., Ireland, and China.

Hey @lyft, looking good @hollymac @dogkiwi.

The good news is that dynamic ridesharing programs demonstrate significant potential for environmental benefits when utilized by drivers and riders with a shared destination, primarily through reduction of VMT, traffic congestion, and associated emissions. They can also help lighten the demand on public infrastructure, including roadways and parking. As a demand-based platform, dynamic ridesharing is highly scalable and can easily expand as these companies pick up steam. And, in contrast to costly transportation infrastructure projects, they are immediately available at little or no cost to the state.  With an estimated 80% of the car seats on the road being empty, finding other people with the same destination to fill them is a no-brainer. The flipside of this coin, however, is that dynamic ridesharing can also facilitate new car trips, where drivers wait for ride requests and go out of their way to get them to their destinations. Although these cars would probably not be prowling the streets like cabs, it seems intuitive that by creating new trips these programs would negate many of the environmental benefits. Since most of these companies are relatively new, there is still little data out there accurately quantifying the VMT reductions in either case.

These startups now find themselves at the forefront of the dynamic ridesharing movement, with yesterday’s decision by the CPUC recognizing that they cannot be regulated through the same lens as charter-party carrier services like taxi and limo companies. In light of the potential environmental benefits, this is a big step in the right direction for the CPUC, as an open rulemaking will best address the novel issues and questions presented by these innovative services. The CPUC has played a prominent role in California’s long history of tackling precedent-setting issues, and this rulemaking is no exception, as it will establish the nation’s first regulatory framework governing a new transportation solution that is beginning to emerge across the country. 

Photos: (top) texting in traffic, by Mo Riza on Flickr; (bottom) Lyft mustache by lizasperling, on Flickr.

Share | | |


Switchboard is the staff blog of the Natural Resources Defense Council, the nation’s most effective environmental group. For more about our work, including in-depth policy documents, action alerts and ways you can contribute, visit

Feeds: Stay Plugged In