Snohomish County, WA Noise Ordinances: Quiet Hours (2026)

Snohomish County adopted Chapter 10.01 SCC pursuant to RCW 70.107 and the state Noise Control Act, incorporating the maximum environmental noise levels from WAC 173-60. SCC 10.01.020 defines 'night' as 10:00 p.m. to 7:00 a.m. on weekdays and 10:00 p.m. to 9:00 a.m. on weekends; 'day' is the remaining hours. SCC 10.01.030 sets quantitative standards by Environmental Designation for Noise Abatement (EDNA), with three classes: Class A (residential), Class B (commercial), Class C (industrial). For sound crossing into a Class A receiving property, the maximum permissible levels are typically 55-60 dB(A) during day and reduced by 10 dB(A) at night. Levels may be exceeded by 5 dB(A) for up to 15 minutes, 10 dB(A) for 5 minutes, or 15 dB(A) for 1.5 minutes in any one-hour period. SCC 10.01.040 prohibits 'public disturbance noise' regardless of decibel level - including loud parties, amplified music audible at 50 feet, and excessive vehicle noise. SCC 10.01.050 exempts emergency work, construction during permitted hours, agricultural activity, sounds from official functions, and sounds within parks. For periodic, impulsive, or pure-tone noise affecting rural or residential property, the maximum permissible levels are reduced by 5 dB(A). Complaints in unincorporated areas go to the Sheriff's Office (425.407.3999 non-emergency); cities like Everett, Lynnwood, Marysville, and Edmonds handle complaints within their boundaries.