Synergies of Combining Demand- and Supply-Side Measures to Manage Congested Streets

Status

Complete

Project Timeline

July 1, 2019 - December 31, 2020

Principal Investigator

Areas of Expertise

Infrastructure Delivery, Operations, & Resilience Travel Behavior, Land Use, & the Built Environment

Campus(es)

UC Berkeley

Project Summary

Congestion pricing has been used in cities to limit flows into congested neighborhoods. Pricing does not necessarily reorganize how flows are served, however. Since organizational inefficiencies tend to arise naturally in congested traffic, combatting this type of congestion by means of pricing alone may require high tolls. This can be quite regressive. Complementary strategies to reorganize flows could help reduce the tolls required to alleviate congestion. The challenge lies in choosing organizing strategies that both diminish workload on a network by diminishing vehicle miles traveled (VMT); and enhance network productivity by reducing vehicle hours traveled (VHT). The research will explore the optimal banning of vehicular left‐turn maneuvers at certain signalized intersections in a city as a traffic reorganization strategy. The prohibitions would be imposed only on those intersections that reside inside select zones within the larger city, and only at select times of day. Preliminary research indicates that imposing left‐turn restrictions in this strategic manner can alone reduce a city’s VMT and VHT by substantial amounts; and be far more effective than banning left turns over an entire city in wholesale fashion. Guidelines will be crafted to assist decision‐makers in restricting left turns in their own cities.