In the most recent reported month of its pilot with the Scoop carpool system, the city of San Mateo took over 1300 cars off the roads and reduced parking demand by about 20 spaces, at a cost of about $2.60 per ride to the city, and about $3.40 to each passenger.  (Drivers get reimbursed an average of $6 per trip).

The pilot is being run by the cities of San Mateo and Foster City until the initial grant funding of $30,000 from San Mateo and $60,000 from Foster City runs out.   The program is available for people who live or work in these cities.  San Mateo expects their funds to hold until March.

The number of trips have been increasing steadily during the pilot period.

 The program has been promoted to the business community via direct mailers, emails to employers, and onsite promotional events for major employers, and with Commute.org. For residents, the program has been promoted via NextDoor, social media, and City email lists.

One helpful feature for passengers is a guaranteed ride home. If a rider doesn’t get a carpool for the ride home, because there is no match or they have to leave early or late, Scoop will reimburse up to $40 for the trip.  While this seems potentially risky for Scoop, this is a common feature provided by transportation demand management services, and experience shows that it is rarely abused.

So far this system is relatively small but extremely cost-effective. The cost of building a new parking spot is $60,000, which works out to $300 per month in amortized capital costs and maintenance over the life of the building, or $10 per day. It is cheaper to the city to subsidize these carpool trips than to build new garage spots for all the commuters to drive alone.  

A not-yet-answered question is how large can this scale – could it reduce the city’s needs to build new parking?   Could it help make a dent in traffic, as part of the city’s suite of trip reduction strategies?

Another important not-yet-answered question is the mode that riders are switching from.  If most are switching from driving alone, the program is helping with traffic and parking.   But if some are switching from personally-matched carpools or public transit, than it is making less of a difference.

For more information, see the San Mateo report below. The slides say confidential but we have permission to publish.