Among the projects included in the 2024 capital budget of the city of Rehoboth Beach is an LED retrofit of lights in the median of Rehoboth Avenue. If that project is executed with all the important issues taken into consideration, it will provide many benefits.
LED lighting reduces energy costs up to 70%, compared to the high-intensity discharge lighting that it will be replacing. LEDs help lower carbon emissions by reducing the demand for electricity, which is still largely generated by burning fossil fuels. This is consistent with legislation currently pending in Dover, the Delaware Climate Change Solutions Act of 2023, being introduced for the purpose of achieving targeted greenhouse gas emissions reductions. This is intended to reduce Delaware’s contribution to climate change. The legislation highlights the importance of efficient energy consumption, and Rehoboth Beach’s retrofit project supports the goals of the act.
The choice of the LED lighting system to be used has a direct impact on human health and on the well-being of wildlife, including birds and insects. An untested rollout of white LED streetlights in England produced worse light pollution for insects than the lighting they replaced. That contributed to an increased decline in the abundance of moth caterpillars, important pollinators that provide essential food for birds and other animals. Insects are a vital part of the natural environment, so the selection of Rehoboth Beach’s lighting design ought to include consideration of that impact.
Red and white light, which contains visible long-wavelength radiation, attracts and disorients nocturnally migrating birds. Birds are less disoriented by green and blue light, which contains less or no visible long-wavelength radiation. Blue warning lights, to which birds do not react, were installed on the Indian River Inlet bridge, which is on an important migration corridor for bats and many species of migrating birds.
Although blue light is optimal from the point of view of birds, humans cannot function safely under blue light. LEDs for street lighting are classified by their color temperature, in degrees Kelvin. The American Medical Association recommends installing street lights of 3,000 K or lower. Twenty-five cities in Connecticut are following those guidelines. LEDs over 3,000 K inhibit the release of the sleep-inducing hormone melatonin in humans, preventing people from sleeping. It would be advantageous for Rehoboth Beach to consider following the medical association’s recommendation for the lower color temperature LED lighting, as well as fully shielding the fixtures, so that they emit no light upward.
The goal of reducing unnecessary light pollution applies equally to all residents of the Delmarva Peninsula. The darker we can keep the sky at night, the safer the birds will be when they’re flying to get to where they need to go.
Steve Cottrell
President, Delaware Audubon
