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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations

This report is an archived publication and may contain dated technical, contact, and link information
Publication Number:  FHWA-HRT-12-053    Date:  November 2012
Publication Number: FHWA-HRT-12-053
Date: November 2012


Casual Carpooling Scan Report

Observations and Lessons Learned from All Cities


Pricing and Incentives

Dynamic ridesharing participants are highly motivated by two incentives: time savings and money savings. Commuters will go to great lengths to realize appreciable time or money savings.

Safety in Numbers

HOV-3 requirements do seem to lead to participants feeling safer (i.e., passengers feel safer when there is a second occupant in the vehicle), but as attested by the Houston visit, a second passenger is not always required for passengers to feel safe getting into a car. In Houston, the scan group saw multiple two-person (driver and rider) carpools form, and they seemed to work fine. Perhaps these carpools may be composed of people who had been participating long enough under HOV-3 rules to become comfortable with many of the drivers and thus also feel comfortable enough to continue slugging in two-person carpools with largely the same drivers.


Infrastructure can play a very important role in helping dynamic ridesharers accumulate time and money savings. Contributing infrastructure included barrier-separated reversible HOV lanes, park-and-ride lots, and direct access to HOV lanes from parking areas.

Role of Transit

Transit and dynamic ridesharing are complementary modes of transportation. Dynamic ridesharers tend to use transit as a backup mode. Transit providers could view these carpoolers as part-time customers and not as competitors.


It is difficult to say what role technology might take in bringing dynamic ridesharing to new locations. A number of Web sites, services, and smart device applications are available on the market but do not appear to be heavily in use yet.


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