Walla Walla County, WA Noise Ordinances: Decibel Limits (2026)

Section 9.20.030(A) sets maximum permissible sound levels for sources located within the county, cross-referencing the zoning district of the sound source against the district of the receiving property: rural-to-rural tops out at 49 dB(A), residential-to-residential at 57 dB(A), commercial-to-commercial at 60 dB(A), and industrial-to-industrial at 70 dB(A), with intermediate combinations set out in the same table. Section 9.20.030(B) applies a parallel table, keyed to state Environmental Designation for Noise Abatement classes A, B and C, to sound sources located outside the county reaching property inside it.

Section 9.20.040 layers on modifications: between 10 p.m. and 5 a.m. on weekdays, and 10 p.m. and 9 a.m. on weekends, every applicable limit drops by an additional 10 dB(A) where the receiving property is residential; periodic, pure-tone or impulsive sound is reduced by 5 dB(A); and short-duration sound gets extra headroom of 5 dB(A) for up to 15 minutes an hour, 10 dB(A) for up to 5 minutes an hour, or 15 dB(A) for up to 90 seconds an hour. Section 9.20.060 exempts aircraft, safety devices, fire alarms, emergency equipment, natural phenomena and unamplified voices, highway maintenance equipment, brief warning devices, and sanctioned parades at all times, while Section 9.20.070 exempts construction equipment, blasting, bells and chimes under 5 minutes an hour, utility repairs, and lawn and garden equipment during daytime hours. Section 9.20.065 removes farm production activity from the chapter entirely.