Sea turtle hatchlings use natural light to guide their journey into the ocean. Because many Florida coastal roadways are adjacent to sea turtle nesting beaches, coastal roadway lighting systems have been known to disorient the hatchlings. To address this situation, the Florida Department of Transportation (FDOT) is investigating alternatives to traditional roadway lighting systems for coastal roadways that will lessen the impacts to sea turtles while providing adequate street visibility. This paper describes an FDOT demonstration project using low-level roadside lighting fixtures and embedded pavement lights instead of overhead luminaires. The authors conducted three tasks as part of this demonstration project: (1) an evaluation of the relative illumination levels of the new lighting system; (2) a determination and evaluation of roadway user opinions of the new lighting system; and (3) an evaluation of crash statistics before and after the installation of the new lighting system. Findings showed that area lighting levels and uniformity were reduced by the elimination of overhead lighting. Although the remaining pedestrian area lights did provide adequate illumination levels along the pedestrian pathway, the presence of non-illuminated areas adjacent to the pathway was problematic in terms of security. However, users generally felt comfortable with the lighting and no security problems were noted during the demonstration. Overall, roadway users were very supportive of the alternative lighting system for the benefit of sea turtle safety. Generally, it was found that younger persons were more supportive of the new lighting system than older persons, and women were more supportive than men. No mode-specific factors were found to be significant in explaining opinion responses. The review of crash reports did not point to any specific roadway lighting issue as a contributing cause.
Abstract