Dark Skies

Globally, light pollution is increasing rapidly: studies say roughly 10 percent more per year. With continually increasing developed land, Loudoun County is no different. From glare from newly lit athletic fields to a change in the hue of the sky from seasonal holiday display uplighting; all the light that we observe impacts wildlife.

Light pollution is the inappropriate or excessive use of artificial light that negatively impacts natural and necessary dark skies. Issues that come along with light pollution include glare, light trespass, and skyglow. (See glossary of terms relating to lighting and light pollution.) As a rapidly developing county, Loudoun is increasingly becoming susceptible to the dangers of increasing light pollution to our natural ecosystems.

Loudoun Wildlife Conservancy supports adhering to dark sky standards set by DarkSky International. In general, DarkSky recommends that outdoor lighting should only be used when and where it’s needed, be no brighter than absolutely necessary, avoid all upward-facing light and minimize blue light emissions.

In response to each new development effort to meet Loudoun’s wants and needs, standards to protect wildlife and preserve our unique environmental resources must be reinforced and put in place. Wildlife suffers most extensively from disrupted nightscapes, but all Loudoun County residents are impacted. Dark skies are a scenic resource to our communities that shouldn’t be understated, especially when one considers Loudoun’s proximity to Sky Meadows State Park, a park officially designated as an international dark skies park.

Excessive nighttime artificial light is a nuisance to those residing near excessively lit places, as many people in Loudoun County are familiar with, but overexposure to artificial light at night can negatively affect human health as well as wildlife stability. In order to curb light pollution, restrictive lighting standards must be applied across the county, year round, to street lamps, homes, parks, businesses, government buildings, schools, data centers and athletic fields. Efforts to reduce light pollution fall largely on county policy and enforcement, but private citizens can take action to minimize the use of artificial nighttime light as well.

Lighting standards must be more thoughtful and constrained in order to protect important wildlife corridors and natural areas. We can all do our part to minimize skyglow in the county for the sake of the wildlife that depend on our dark skies. Ensuring that lights on your property are used to the least degree possible and speaking up on development proposals for excessive lighting go a long way to protecting ourselves, our environment and the creatures that need darkness.

For more information, read Loudoun Wildlife Conservancy’s white paper “Dark Skies and Loudoun’s Wildlife.”