Spring 2002

ME/IE 8773-8774

RAMP METERS ON TRIAL

by

David Levinson
Assistant Professor
Department of Civil Engineering
University of Minnesota

Wednesday, February 27, 2002
3:30-4:30 p.m.
Room 108 ME
Broadcast on UNITE Channel A
Coffee and cookies will be available in 125 ME following the seminar

Ramp meters in the Twin Cities have been the subject of a recent test of their effectiveness, involving turning them off for 8 weeks. This paper analyzes the results with and without ramp metering for several representative freeways during the afternoon peak period, depending on data availability. Seven performance measures: accessibility, mobility, equity, productivity, consumer surplus, travel time variation and travel demand responses are compared. It is found that ramp meters are particularly helpful for long trips relative to short trips. On Route 169, trips more than 3 exits in length benefit, while those 3 exits or less are hurt by ramp meters. Ramp metering, while generally beneficial to freeway segments, may not improve trip travel times (including ramp delays). Travel time variation is reduced as another benefit from ramp meters. Non-work trips and work trips do respond to ramp meters, but via different ways. The results are mixed, suggesting a more refined ramp control algorithm which explicitly considers ramp delay is in order.

Prof. David Levinson teaches Transportation Engineering, Planning, and Economics in the Civil Engineering Department at the University of Minnesota. He recently completed the book Financing Transportation Networks, to be published in March 2002. A graduate of the University of California at Berkeley, his dissertation "On Whom the Toll Falls" examined toll road policy. He is the recipient of the 1995 Charles Tiebout Prize in Regional Science.

Informal Faculty Luncheon: Wednesday, February 27, 2002, 11:30 a.m. Prof. Levinson will be able to attend.