Sun Prairie, WI Outdoor Lighting: Dark Sky Rules (2026)

070 regulates exterior lighting citywide, stating in its purpose clause that the goal is to control spill-over light and glare affecting drivers, pedestrians and neighboring land uses, and to prevent nuisances. 1, Orientation of Fixture, is the operative rule: no exterior lighting fixture may be oriented so that the lighting element itself, or a transparent shield covering it, is visible from a property located within a residential zoning district. The code frames shielded luminaires and careful fixture placement as the way to comply, effectively steering commercial, institutional and multifamily developments toward full-cutoff or shielded fixtures whenever a residential lot sits nearby.

The requirement applies to all private exterior lighting within the city's zoning jurisdiction under subsection B, though it exempts lighting in public rights-of-way and on public property. Every lighting plan has to be shown on the site plan required for development approval under subsection C, so compliance gets checked at the permitting stage rather than left to complaint-driven enforcement after installation. 6 rather than forced retrofits.