Slugging in Houston — Casual Carpool Passenger Characteristics

In the last 30 years, determined travelers have developed a new method of travel that offers the benefits of traveling on an HOV lane without forming traditional carpools. Casual carpools, also known as “slugging,” are impromptu carpools formed among strangers to meet the occupancy requirements of HOV lanes. In this research, survey respondent data from Houston, Texas, were used to examine casual carpool passengers. Results of the analyses revealed that being on a commute trip, making more trips per week, being between the ages of 25 and 34, and having professional/managerial or administrative/clerical occupations all increased the likelihood of a traveler choosing to casual carpool. Additionally, having a household income between $25,000 and $35,000 significantly reduced the likelihood of casual carpooling. Understanding the types of travelers who casual carpooled and the information gleaned in these analyses can be used to better evaluate HOV and HOT lane use and performance. Casual carpool passengers can comprise a significant portion of HOV/HOT lane person movement and should be considered when investigating HOV or HOT lane implementation.