Like climate change, light pollution is an eco-problem that's tough to pin-point and even tougher to control. It happens when we fail to properly shield or direct streetlights, resulting in uncomfortable glare; or when our neighbor's probing porch light forces us to lower our blinds. Controlling our artificially induced night glow does more than offer better sky-gazing opportunities. Researchers have found strong correlations between light pollution and certain types of cancers, as well as disruptions in wildlife health and movement. In addition, glare caused by inefficient lighting impairs drivers' and pedestrians' night vision, creating more dangerous roadways.
But a collective dimming of the lights won't happen without municipal lighting ordinances, which work to make sure light is directed only where it is needed. Most towns have no regulations regarding how light is wasted, or the how the sky is illuminated. But a few are taking action, such as Flagstaff, Arizona, and Borrego Springs, California, two communities that have earned accolades from the International Dark-Sky Association (IDA) for their visibly darkened skies, the result of strong, enforced lighting ordinances.
Debra Briggs Norvil of Homer Glen, Illinois, used to be able to see the Milky Way from her backyard, but she says that's changed in the last 25 years due to increased population and sky glow. Thanks to a 2007 local lighting ordinance, however, she may yet be able to do some serious stargazing again. In drafting the town ordinance in 2007, Norvil referenced the U.S. Pattern Outdoor Lighting Code, written by Chris Luginbuhl of the U.S. Naval Observatory's Flagstaff station. Homer Glen's code allows full cut-off-outdoor lighting--meaning light is directed downward--for fixtures above 1,100 lumens and limits light trespass to 0.1-foot candles over property lines. A full moon high in the sky doesn't exceed 0.05-foot candles, explains Norvil, "so a 0.1-foot candle is more than double a full moon's brightness." Code applies to new lighting, and a sunset clause requires all lighting to be up to code by 2018. The densely populated suburb of Eatontown, New Jersey, adopted its first lighting ordinance in 1993 for all new lighting installed; A revision in 2001 includes existing lighting. Eatontown's rules emphasize uniform lighting, shielded light fixtures and limiting light trespass.
People tend to support overly bright streetlamps and other outdoor lights for safety reasons. …