Trinity County, CA Noise Ordinances: Vehicle Noise (2026)

The Trinity County Code's traffic title (Title 10, Vehicles and Traffic) adopts and supplements the California Vehicle Code but contains no separate muffler or exhaust-noise provision - it covers speed limits, stop signs, weight limits, parking, and abandoned vehicles, not exhaust sound. The only place 'muffler' appears in the County Code is Chapter 8.44 (Ewing Lake Recreation Area), Section 8.44.030, which makes it unlawful to 'operate any motor vehicle without a muffler system conforming to the provisions of the California Vehicle Code.' That confirms the County defers to state law for vehicle noise. Under the California Vehicle Code, Section 27150(a) provides that 'every motor vehicle equipped with an internal combustion engine and subject to registration shall at all times be equipped with an adequate muffler in constant operation and properly maintained to prevent any excessive or unusual noise,' and 'no muffler or exhaust system shall be equipped with a cutout, bypass, or similar device.' Section 27151 prohibits modifying an exhaust system to amplify or increase noise beyond Section 27150 or the Article 2.5 limits (Section 27200 et seq.); for vehicles with a gross vehicle weight rating under 6,000 pounds (other than motorcycles), a sound level of 95 dBA or less complies. Section 23130 sets on-highway noise limits by speed zone. These state provisions are enforced by the California Highway Patrol and the Trinity County Sheriff on county roads and state highways (3, 36, and 299) countywide. Recreational vehicle noise on specific County lands such as Ewing Lake is additionally tied to the Vehicle Code muffler standard by Section 8.44.030.