Caldwell, ID Noise Ordinances: Aircraft Noise (2026)

The APO-2 Airport Noise Abatement Overlay Zone sits in a rectangular band to the northeast of the Caldwell airport, beginning where the APO-1 zone ends and extending another half mile. Any use permitted or specially permitted in the underlying base zone remains available in APO-2, but building permit applications for new residential construction, or residential additions exceeding 200 square feet of enclosed space, must show that construction methods reduce indoor noise exposure by at least 30 decibels from the noise measured immediately outside. The applicant, not the city, carries the burden of proving compliance.

Rezoning, annexation, building permit, special use permit and subdivision plat applications inside APO-2 must also notify future purchasers or tenants, on both the plat and the deed or lease, that the property may be exposed to aircraft noise and related effects from airport operations. Manufactured and mobile homes built to current HUD and industry standards are exempt from the notification requirement. Under Section 10-11-02-8, every requirement of APO-2 also applies with equal force in the more restrictive APO-1 zone closer to the runway, and the city has adopted the FAA's Part 77 object height limits for the airport vicinity.

Section 10-11-02-9 additionally requires a recorded avigation easement granted to the city before a rezone, annexation or building permit in either overlay zone is finalized, and Section 10-11-02-11 routes any rezoning, subdivision, or variance application touching either zone to the Airport Commission for comment before the Planning and Zoning Commission or City Council acts.