In January, I attended the 99th Annual Meeting of the Transportation Research Board (TRB) to take in this year’s theme, A Century of Progress: Foundation for the Future. The TRB brings together the preeminent transportation researchers, practitioners, and policy-makers from government, industry, and academic institutions for a week of presentations and discussions on the present and future of transportation systems. From asphalts to zebra crossings, the experts you seek are at TRB.
For obvious reasons, one of the presentations I was most excited to see was the University of Washington’s Qing Shen, Professor of the Department of Urban Design and Planning, and Yiyuan Wang, Ph.D. Student, Interdisciplinary Ph.D. Program in Urban Design & Planning. Their presentation, Building partnership between transit agency and shared mobility companies: app-based carpooling the Seattle Region, investigated the impact of King County Metro’s partnership with Scoop in a carpool incentive pilot across the early part of 2019.
It would be an understatement for me to say the results are promising. The analysis presented shows the potential of shared commuting opportunities working at a much larger scale than has historically been possible.
In their working paper, Shen and Wang note the historical difficulties in organizing scalable carpooling solutions, while recognizing that most of this academic attention predates the development of mobile communication technologies. Leveraging the pilot partnership between King County Metro and Scoop, the researchers were able to evaluate how advances in technology-enabled carpooling and facilitated incentives impacted key metrics for King County Metro, like Vehicle Miles Traveled (VMT) and Single-Occupancy Vehicle (SOV) rates.
Over five months, King County Metro’s Carpooling Incentive Fund incentivized commuters to use Scoop to attempt or continue carpooling as a means of commuting. The incentive fund provided $2 for each participant in a matched and completed carpool during the pilot period. Whether a Driver or a Rider, as long as the carpool trip was verified and completed, participants were eligible for the incentive.
The UW team looked at data from over 200,000 Scoop trips and paired this data with survey responses from commuters to measure the fund’s impact. The main highlights in their analysis indicate that Scoop usage:
- Was highly adopted by eligible commuters
- Significantly decreased SOV trips, and
- Reduced commuter VMT during the pilot period
Specifically, the number of Scoop trips rose from 24,268 in the first month to 53,239 in the fifth month, an average growth of 17% month-over-month.
Furthermore, whereas 57% of survey respondents said driving alone was their primary commute before adopting Scoop, only 9% said so after the fact. A detailed statistical model showed, after controlling for an array of individual characteristics, that Scoop was strongly responsible for the reduction in SOV commute trips, and there was an estimated decrease in vehicle miles traveled by about 900,000 to 1,000,000, effectively resulting in a VMT reduction of $0.40 per mile.
From a public policy perspective, it’s clear that utilizing technology-enabled carpool incentives deliver significant benefits in terms of reducing VMT, emissions, and SOV rates of commuters. We look forward to continuing this body of research with the UW team and our other partners.