Snohomish County, WA Environmental Rules: Vehicle Idling Restrictions (2026)
Key Facts
- Idling limit
- 10 minutes at a time, at night
- Vehicles covered
- Stationary trucks over 10,000 lbs GVWR
- Where it applies
- Rural and residential districts only
- First offense fine
- $50 civil infraction
- Repeat within 24 hours
- Misdemeanor, up to 90 days/$1,000
- Enforcing agency
- Snohomish County Sheriff's Office
Summary
In unincorporated Snohomish County, running or idling a stationary truck over 10,000 pounds GVWR for more than ten minutes at a stretch at night is classified as a public disturbance noise. The rule applies only in rural and residential districts and is enforced by the Sheriff's Office under SCC 10.01.040(2)(d), with fines starting at $50.
(2) Public Disturbance Noises, at Night in Rural or Residential Districts. Sounds resulting from the following activities are determined to be public disturbance noises when they occur at night and noise is received on property in a rural or residential district. ... (d) The operation or idling, for more than ten minutes at a time, of stationary trucks weighing in excess of 10,000 pounds GVWR, except vehicles engaged in emergency work exempted under section 10.01.050(1)(g).
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through legislation passed August 12, 2026).
Full Breakdown
SCC 10.01.040(2) makes certain sounds public disturbance noises when they happen at night and are received on property in a rural or residential district, and subsection (d) singles out "the operation or idling, for more than ten minutes at a time, of stationary trucks weighing in excess of 10,000 pounds GVWR." Night is defined in SCC 10.01.020(18) as 10:00 p.m. to 7:00 a.m. on weekdays and 10:00 p.m. to 9:00 a.m. on weekends. Rural districts cover zones such as Rural-5 Acre, Rural Conservation and Forestry; residential districts cover the R-20,000 through R-7,200, Townhouse and Multiple Residential zones, per SCC 10.01.020(7).
Vehicles doing emergency work exempted under SCC 10.01.050(1)(g), meaning emergency equipment used for law enforcement or public health and safety, are not covered. The Snohomish County Sheriff or a deputy sheriff administers and enforces this public disturbance noise provision under SCC 10.01.080(1); the planning and development services administrator handles the separate quantitative sound-level standards instead. A driver can also apply to the noise administrator for a Public Disturbance Exemption Permit under SCC 10.01.050(6) if a longer idling period is unavoidable, but that requires a $150 non-refundable application filed at least 45 days ahead, posted notice, and a 30-day public comment period before any permit issues.
Violations & Fines
A first violation is a civil infraction carrying a $50 penalty under SCC 10.01.080(3). A second violation of a like nature by the same person within one year doubles the fine to $100. If the same person commits a second violation within 24 hours of the first, it becomes a misdemeanor punishable by up to 90 days in jail and/or a fine of up to $1,000, and three violations within a year trigger misdemeanor treatment for any further violation within a year of the last adjudication.
Frequently Asked Questions
Does the 10-minute idling limit apply during the day?
What trucks does the rule cover?
Are emergency vehicles exempt from the idling limit?
Who investigates a complaint about a truck idling overnight?
Sources & Official References
Other rules in Snohomish County
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