Caldwell, ID Noise Ordinances: Vehicle Noise (2026)

" Subsection A makes it unlawful for any motor vehicle to use air compression brakes within the city limits of Caldwell, with a narrow carve-out: the brakes may still be used under emergency circumstances necessary to prevent an accident or injury to persons or property. Subsection B exempts motor vehicles owned and operated by a fire department from the prohibition, recognizing that fire apparatus may need the extra stopping power the brakes provide. Unlike the vehicle stereo rule in section 07-13-04(1) and the general noise curfew in section 07-13-03, the jake brake ban carries its own penalty track in subsection C: a violation is an infraction, not a misdemeanor, and is punished at the fixed penalty set for moving traffic infractions under Idaho Infraction Rule 9(b)(5) rather than the article's general misdemeanor penalty in section 07-13-06.

The rule, adopted by Ordinance 2994 on April 6, 2015, targets the long, sharp compression-release sound produced when a diesel truck engine brake decelerates on Caldwell's streets, a noise source distinct from stereos, horns or machinery covered elsewhere in the noise article. Because the ban applies within the entire city limits and around the clock, truck drivers routing through Caldwell on the interstate corridor or downtown streets must rely on the service brakes instead, and the emergency exception is read narrowly to cover only genuine collision-avoidance situations rather than routine downhill grades.