Shoreline, WA Noise from Specific Sources: Car Alarm Limits (2026)

Shoreline Municipal Code § 9.05.070 lists specific sources of sound that automatically qualify as public nuisance noise, and subsection (A) targets horns and sirens: frequent, repetitive or continuous sounding of any horn or siren attached to a motor vehicle or watercraft is unlawful except as a warning of danger or as specifically permitted or required by law. A car alarm that repeatedly blares in a parking lot or driveway, or a boat horn sounded without an emergency, falls within this definition once it becomes frequent, repetitive or continuous.

The chapter's opening sentence sets the underlying standard: it is unlawful for any person knowingly to cause or make, or to allow to originate from their property, sound that unreasonably annoys, injures, interferes with, or endangers the comfort, repose or health of another person. Enforcement runs through § 9.05.090: the code enforcement officer or the Shoreline Police Department, which polices the city under a King County Sheriff's Office contract, may issue a civil infraction carrying a $100.00 fine, and each day the nuisance continues counts as a separate violation.

Civil infractions are issued under SMC § 20.30.770(A) and Chapter 7.80 RCW, and a recipient may contest the infraction by appealing to the King County District Court, West Division, in Shoreline. The city also reserves the right to pursue any other remedy the law allows. Unlike the chapter's numeric decibel limits in § 9.05.040, subsection (A) does not require a sound-level reading: repetition and duration alone establish the violation, which makes a malfunctioning alarm enforceable on a neighbor complaint alone.