Planners propose clearer dark-sky rules, numeric lumens caps and trespass limits

Planning staff presented proposed updates to Appendix D (outdoor lighting) to modernize standards and make them easier to administer while continuing dark-sky protections. The draft would keep prohibitions on uplighting and require illumination plans but would remove the previous Class 1–3 categories in favor of a residential/nonresidential distinction with numeric caps and trespass metrics.

Joanne Marie Andrade said the draft sets caps of 25,000 lumens per net acre for single-family residential and 100,000 lumens per net acre for nonresidential sites, and proposed measurable trespass limits such as "0 foot candles" at residential property lines adjacent to commercial lighting. "The draft shifts to a more straightforward distinction between residential and non residential," she said, adding the intent is to provide the lowest amount of light reasonably needed.

The changes also add specific standards for outdoor sales areas, illuminated signs, sports lighting and seasonal lighting; commissioners did not object to retaining curfews and color-temperature guidance and asked staff to ensure the rules are clear and enforceable.