Effect of speed feedback device on speeds in interstate highway work zones

Providing speed feedback to motorists may improve their compliance with speed limits in work zones. Speeding has been identified as one of the major reasons for crashes in work zones and there is a need for effective speed reduction strategies in construction zones. Speed photo enforcement with speed feedback system is a promising technology for speed management in work zones. A component of the photo enforcement system is the speed feedback display device that has some effects in reducing the speeds of motorists in work zones. Data were collected on an interstate highway work zone in three phases and statistical analysis was performed to determine the temporal effect of the speed feedback device. It was found that feedback device was effective in reducing average speed by 4.4 mph in a few days after the deployment. After three weeks of operating the feedback system, the average speed was further reduced by 2.3 mph. Both these reductions were statistically significant. Thus, at this location, providing speed feedback reduced the speeds of the motorists not only immediately after the system was deployed, but also three weeks after deployment. Copyright ASCE 2006.