Mar 19

Work Zone Driveway Assistance Devices (DADs):  Past Research & Evaluation of Display Strategies

Event Details

March 19, 2021


This free webinar will begin at 12:00 p.m. (Central Time)


Details to access the Webex webinar will be emailed along with a confirmation after you register.

Event Contact
Keith Knapp
InTrans, Iowa LTAP


The Driveway Assistance Device (DAD) is an experimental device used to direct traffic onto a bi-directional, single-lane work zone from a driveway or side street. This device uses alternating flashing arrows to indicate the traffic flow direction along the work zone segment in order to reduce wrong-way driving. Although several states have experimented with DADs in various work zone settings, there remains a lack of consensus regarding the design aspects and the general effectiveness. To help address these issues, research was performed to evaluate various aspects of the DAD design, including auxiliary sign messages, signal configuration, and arrow color.

Speaker Bio

Tim Gates is an Associate Professor of Civil Engineering at Michigan State University. Tim has 20 years of research experience in traffic safety, engineering, operations, and design. He has led projects on work zone traffic control for a variety of agencies, including the Michigan DOT, FHWA, SWZDI and others. Tim is active in the Transportation Research Board, where he chairs the standing committee on Traffic Control Devices. He earned his Bachelor’s and Master’s degrees in Civil Engineering from MSU and his Ph.D. in Civil Engineering from the University of Wisconsin.