THE POTENTIAL FOR REDUCED LIGHTING ON ROADWAYS

A summary is presented of a Federal Highway Administration (FHWA) study to determine if roadway lighting can be reduced or eliminated during nighttime periods when traffic density is much lower than design capacity, without significantly reducing driver ability to safely and effectively control the vehicle. The study consisted of the following tasks: review of the literature; development of a conceptual model of visibility needs and the identification of alternative reduced lighting techniques; determination of the costs, potential energy savings, and legal implications; and the determination of the effect of such techniques on driver detection of simulated roadway hazards under actual traffic conditions. The study found that technology exists for implementing all of the identified reduced lighting techniques with benefit-cost ratios greater than 1.0 for all but the most complex techniques. It was also found that driver detection performance decreased under each reduced lighting technique. It is noted that legal problems may result with the use of reduced lighting techniques.