Responsible Lighting
Lighting plays an essential role in modern life, supporting safety, productivity, and quality of life. Our goal is not to eliminate artificial light, but to encourage its thoughtful and responsible use. Excessive and poorly designed lighting has measurable negative effects on human health, wildlife, and the natural environment — impacts that will only grow as our population continues to expand.
The following guiding principles, developed by Dark Sky International, offer a framework for lighting practices that balance the needs of people and communities with the preservation of our natural night skies.
The image below shows a before and after for a local house where the home owners replaced the fixtures and lights according to these principles. As can be seen, very little light is shining up because of the shielding, direct glare is eliminated, the ambience is pleasing and there is plenty of light.
We do not recommend specific lights because there are thousands of dark sky compliant lights available at hardware stores or specialty lighting stores. For most cases, the following practical tips are all you need to know. More information and examples can be found in our printable documents below.
Shielding Use fixtures completely shield the bulb and direct light downward and not sideways or upward. The reduction of light trespass and direct glare not only fosters good neighborhood relations, but also dramatically improves visibility on your own property by reducing glare.
Brightness Because of the lack of glare, the amount of light needed to provide good visibility is also reduced. A 200-800 lumen bulb in most situations is entirely adequate, providing excellent visibility and a pleasing ambience.
Color Although Dark Sky International recommends lights have a color correlated temperature (CCT) of less than 3000 kelvin, even lower CCTs provide increasing benefits. Amber bulbs, sometimes called "bug" lights (because bugs are not attracted to them), provide a pleasing ambience as well as dramatically reducing glare and skyglow. Be aware that not all amber LED bulbs are equivalent - some have a greenish tinge that increases glare and skyglow impacts and also appear unattractive to many.
Lighting Resources
Codes
The Winthrop municipal code “Outdoor lighting 15.06” implements some of the dark sky requirements for outdoor lighting. These include full-cutoff shielding, limits on light trespass, and color correlated temperature (<3000 K). Illuminated signs are addressed in several places in the code. These codes generally limit sign illumination to indirect, shaded lighting. Self- and internal illumination of signs is generally prohibited.
The Twisp municipal code has some requirements for outdoor lighting here. These requirements place limitations on light and glare and generally promote fully shielded light fixtures. Chapter 15.20 (Signs) contains a few lighting requirements for signs.
We are engaged in an ongoing process to develop codes for the county.