City of Marysville
Noise Ordinance
Discussion
June 20, 2023
Purpose of Public Workshop
»Discuss whether to direct staff to draft a Noise
Ordinance
»Currently the City does not have a noise standard.
»A noise ordinance would allow the City to set a standard for new development and assist in environmental
review.
What is Noise?
»Noise impacts are generally defined
as a loud, unpleasant, unexpected,
or undesired sound that is typically
associated with human activity and
that interferes with or disrupts
normal activity
This Photo by Unknown Author is licensed under CC BY-SA-NC How is Sound Measured?
»Sound is generally characterized by several variables, including frequency and intensity. Frequency describes
the pitch of the sound and is measured in Hertz (Hz),
while intensity describes the sound’s loudness and is
measured in decibels (dB). Decibels are measured using
a logarithmic scale.
Noise Perception
»The minimum change in the sound level of individual events that an average human ear can detect is about 1 to 2 dB. » A 3 to 5 dB change is readily perceived.
»A change in sound level of about 10 dB is usually perceived by the average person as a doubling or a halving of the sound’s loudness.
Increases in sound
»If a sound’s intensity is doubled, the sound level
increases by 3 dB, regardless of the initial sound
level.
» For example: 60 dB + 60 dB = 63 dB, and 80 dB + 80
dB = 83 dB.
Noise Standards- Day Night Average (Ldn)
» Day-Night Average Noise Level (Ldn) describes noise exposure over a 24-hour period. It is calculated by adding a 10-decibel penalty to sound levels at night (10:00 p.m. to 7:00 a.m.) to compensate for the increased sensitivity to noise during the quieter evening and nighttime hours.
» Ldn is used by jurisdictions (such as the State of California and local jurisdictions) to define acceptable land use compatibility with respect to noise.
Caltrans Noise Standards
Noise from Caltrans projects is regulated by Caltrans
Standard Specifications Section 14- 8.02, “Noise Control,” which states:
» Do not exceed 86 dBA at 50 feet from the job site
activities from 9:00 p.m. to 6:00 a.m.
Highway traffic and construction noise as it relates
to noise sensitive land uses
» 65 Ldn for exterior noise
» 45 Ldn for interior noise
» Projects that exceed the standard would be required
to provide mitigation.
Proposed Changes
11 Next Steps
»Direct Staff to draft a Noise Ordinance
»Draft Noise Ordinance review with a
recommendation by the Planning Commission
»City Council Public Hearing
»In addition, General Plan update will also address
Noise