Informal Commuting Networks Show Promise for Mobility

  • Author: Andrew Carpenter
  • Date: October 11, 2018

There is a niche commuting pattern in some large metropolitan areas: casual carpooling. The practice is most common in San Francisco, Houston and Washington, D.C., where it is called slugging.

Though the word “slug” might imply a lack of speed, this informal network of commuters actually speeds up participants’ trips. Slugging helps people driving from longer distances – outside the Beltway, in D.C.’s case – to use high occupancy toll (HOT) express lanes into the city, without paying a toll, while also reducing the number of cars utilizing the highway.


How does it work?

Drivers pull up to sluglines – the designated spots where passengers line up – and announce their destination such as the Pentagon, L’Enfant Plaza, or Downtown for D.C. commuters. Passengers closest to the front of the line who are going to the same general area will get in until there are enough to access the High Occupancy Toll (HOT) lanes, which usually require at least three occupants to avoid tolls. Passengers get out near their destination, and the process repeats for the afternoon commute away from the city.

A key factor in slugging is that passengers don’t pay for their rides, and drivers save money by bypassing tolls. The value for drivers and passengers alike is that they get to bypass traffic – and there is almost always traffic – by using express lanes without having to pay for them, as opposed to paying a toll to use them alone.


Opportunities for Mobility Managers

Informal networks can be a potential opportunity for mobility managers. In places like D.C., San Francisco, and Houston, this is a well-established practice that is easy to connect to. Outside of those cities, casual carpooling exists to some extent in many metropolitan regions, but is less established or pervasive. But wherever large numbers of workers must drive significant distances to reach their jobs, the potential for casual carpooling is there.

To better understand how it might work, and how a community could establish their own slugging networks, this compendium of flexible carpooling knowledge is a great place to start.

By finding the informal or casual mobility networks in a region, mobility managers can open up a new avenue of options for their clients. Though, by nature, many of these groups form organically through social networks or word of mouth, mobility managers can harness them to solidify and ground them, helping the networks thrive by directing people into the system. For example, mobility managers could find a way to carve out a space or host a forum that allows people to make connections and get themselves into cars.

The fact that these networks form organically, even developing unique names like slugging, speaks to their viability, which is especially impactful for those who need to travel into cities for opportunities or amenities but cannot afford the high price tag of long-distance round trips. Such a network can work to mobility management’s favor by building a self-reinforcing system that can flexibly serve the people who need it.


Image Credit: Sharon Hahn Darlin, Flickr, CC BY 2.0


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