Twin Falls County, ID Outdoor Lighting: Dark Sky Rules (2026)

Twin Falls County's zoning code does not carry a general, county-wide outdoor lighting or dark-sky ordinance for the unincorporated area outside the cities' areas of impact. The one place the code regulates how outdoor lighting is aimed is the Airport Overlay (AP) zone, the district around the county's airports. Section 8-6H-4(A) flatly prohibits any pulsating, flashing, rotating, oscillating or other attention-getting lighting device in the zone, and separately requires that floodlights, spotlights or other lighting fixtures be arranged or shielded so they do not cast illumination upward, above an imaginary line drawn parallel to the ground from the light source, a full-cutoff style shielding rule aimed at keeping light out of the flight path rather than at reducing sky glow generally.

The same section bans glare-producing building materials on any structure or land use in the AP zone under subsection B, and separately restricts electromagnetic radiation that could interfere with aircraft or airport radio navigation under subsection C. Outside the AP zone, the closest analog is § 10-3-11(D), which requires street and other outdoor lighting in a planned unit development to be shielded or adequately focused so it does not send light or glare beyond the development's own service area, but that rule applies only inside an approved PUD, not to lighting on an ordinary unincorporated lot.

The Zoning Administrator reviews AP zone and PUD lighting plans as part of the underlying permit or PUD approval; there is no freestanding outdoor lighting permit.