18.110.050 Noise.
A. Purpose. Certain noise levels must be tolerated by all citizens in order for the normal functions of city life to continue. However, any loud, unnecessary, or unusual noise that is excessive, disruptive, and/or annoying is subject to regulation as provided in this chapter. Children playing, construction equipment, barking dogs, amplified musical instruments, trash trucks, airplanes, and loud parties are all examples of noise found within the community.
B. Prohibited Noises, Standards of Acceptable Levels.
1. The following activities listed in subsections (B)(2) through (B)(5) of this section are prohibited if they:
a. Produce any loud, unnecessary, or unusual noise that is excessive, disruptive, and/or annoying; and
b. Are continuous or intermittent for a period of at least 15 minutes; or
c. Occur after 10:00 p.m. but before 6:00 a.m. (noise produced as a result of construction or landscape maintenance on golf courses and parks may begin at 5:00 a.m.); and
d. Are plainly audible beyond the property line of the property on which conducted; and
e. Disturb the peace and quiet of a neighborhood, a reasonable person of normal sensibilities, or are not a temporary event.
2. Allowing or causing any noise by using, operating, or permitting to be played any electronic music device, television, amplifier, musical instrument, or instrument, machine or device used for the production, reproduction or emission of sound.
3. Creating or allowing any noise in connection with the loading or unloading of any vehicle.
4. Owning, possessing, harboring, or permitting any animal or bird which frequently or for continuous duration howls, barks, meows, squawks, or makes other sounds.
5. Allowing or causing any malicious or willful shouting, yelling, screaming, or any other form of raucous vocalization by a person or group of people.
C. Other Prohibited Noises.
1. Use of any automobile, motorcycle or other vehicle, engine or motor of whatever size, stationary or moving, instrument, device or thing, in such a manner as to create loud and unnecessary grating, grinding, rattling, or other noise.
2. Operating any mechanical device operated by gasoline, or otherwise, without having a muffler, in good working order and in constant operation, to prevent excessive or unusual noise and smoke; and no person shall use a muffler cutout, bypass, or similar device.
3. Operating or permitting the operation of any sound amplification system in or on a vehicle in such a manner or with such volume as to annoy or disturb the peace and quiet of any reasonable person of normal sensibilities or neighborhood in the vicinity.
4. Operating or permitting the operation of any sound amplification system in or on a vehicle in such a manner that the sound is plainly audible at a distance of 50 feet, or in such a manner that it causes a person’s normal sensibilities to be aware of vibration accompanying the sound at a distance of 50 feet.
5. Maintaining or operating an outdoor speaker that is affixed to any structure or placed upon any property where:
a. The speaker is audible for a distance of more than 50 feet from the source; or
b. The speaker is 250 feet or closer to a residential district. This restriction shall not apply to intercommunication systems that are utilized from 9:00 a.m. to 6:00 p.m. for the sole purpose of conducting the internal business affairs of the establishment.
This provision does not prohibit use of an outdoor speaker where a temporary use permit has been granted for a special event.
D. General Exemptions. The following activities are exempt from the provisions of this chapter:
1. Emergency work necessary to restore property to a safe condition following a fire, accident or natural disaster; to restore public utilities; or to protect persons or property from an imminent danger;
2. Sound made to alert persons to the existence of an emergency, danger, or attempted crime;
3. Activities or operations of governmental units or agencies;
4. Parades, concerts, festivals, fairs, or similar activities that have been approved by the city for a temporary use permit for special events;
5. Athletic, musical or cultural activities or events (including practices and rehearsals) conducted by or under the auspices of public or private schools, and public or private colleges or universities; and
6. Construction, repair, remodeling, demolition, drilling, landscape maintenance, landscaping, lawn or yard work, wood cutting, including crafts and hobbies, or excavation work conducted between 5:00 a.m. through 8:00 p.m. Mondays through Fridays. Also, a person may engage in or allow such activities at that person’s residence between 6:00 a.m. and 8:00 p.m. on Saturdays and Sundays.
E. Temporary Exemptions.
1. The city manager or designee is authorized to grant a temporary exemption from the requirements established by this chapter if such temporary exemption would be in the public interest and there is no feasible and prudent alternative to the activity, or the method of conducting the activity, for which the temporary exemption is sought.
2. A temporary exemption must be in writing and signed by the city manager or designee and must set forth the name of the party granted the exemption, the location of the property for which it is authorized, and the date(s) and time(s) for which it is effective.
3. A temporary exemption may be granted only for the period of time that is reasonably necessary to conduct the activity, which in no case may exceed 30 days, unless otherwise specified.
4. The following factors shall be considered by the city manager or designee in determining whether to grant a temporary exemption:
a. The balancing of the hardship to the applicant, the community and other persons in not granting the variance against the adverse impact on the health, safety and welfare of persons adversely affected and any other adverse effects of the granting of the variance;
b. The nearness of any residence or residences, or any other use;
c. The level of the sound to be generated by the event or activity;
d. Whether the type of sound to be produced by the event or activity is usual or unusual for the location or area for which the variance is requested;
e. The density of population of the area in which the event or activity is to take place;
f. The time of day or night which the activity or event will take place; and
g. The nature of the sound to be produced, including but not limited to whether the sound will be steady, intermittent, impulsive or repetitive.
F. Persons Responsible for Noise Violations. The person responsible for an activity that violates this section shall be deemed responsible for the violation. If the person responsible for an activity that violates this section cannot be determined, the owner, property manager or agent of the owner, sponsor of the event, lessee or occupant of the property on which the activity is located shall be deemed responsible for the violation. Any person in attendance who engaged in any conduct causing the disturbance may also be deemed responsible for the violation. After three violations on the same property, in addition to the individuals listed above, the owner of the property may also be deemed responsible for the violation.
G. Exterior and Interior Noise Limits Related to Land Use or Activities Permitted by Zoning. No use or activity permitted by the zoning code shall create noise levels that exceed the following standards. The maximum allowable noise levels do not apply to noise generated by automobile traffic or other mobile noise sources in the public right-of-way.
Land Use Receiving the Noise | Noise-Level Descriptor | Exterior Noise Level Standard in Any Hour (dBA) | Interior Noise-Level Standard In Any Hour (dBA) | ||
|---|---|---|---|---|---|
Daytime (6:00 a.m.–10:00 p.m.) | Nighttime (10:00 p.m.–6:00 a.m.) | Daytime (6:00 a.m.–10:00 p.m.) | Nighttime (10:00 p.m. – 6:00 a.m.) | ||
Residential | L50 Lmax | 55 70 | 45 60 | 40 55 | 30 45 |
Medical, convalescent | L50 Lmax | 55 70 | 45 60 | 45 55 | 35 45 |
Theater, auditorium | L50 Lmax | - - | - - | 35 50 | 35 50 |
Church, meeting hall | L50 Lmax | 55 - | - - | 40 55 | 40 55 |
School, library, museum | L50 Lmax | 55 - | - - | 40 55 | - - |
1. Adjustments to Noise Limits. The maximum allowable noise levels of Table 18.110.050.G, Exterior and Interior Noise Limits, shall be adjusted as follows. No more than one increase in the maximum permissible noise level shall be applied to the noise generated.
a. Ambient Noise. If the ambient noise level at a noise-sensitive use is 10 dBA or more below the standard, the allowable noise standard shall be decreased by five decibels.
b. Duration. The maximum allowable noise level (L50) shall be increased as follows to account for the effects of duration:
i. Noise that is produced for no more than a cumulative period of 15 minutes in any hour may exceed the noise limit by five decibels;
ii. Noise that is produced for no more than a cumulative period of five minutes in any hour may exceed the noise limits by 10 decibels; and
iii. Noise that is produced for no more than a cumulative period of one minute in any hour may exceed the noise limits by 15 decibels.
c. Character of Sound. If a noise contains a steady audible tone or is a repetitive noise (such as hammering or riveting) or contains music or speech conveying informational content, the maximum allowable noise levels shall be reduced by five decibels.
H. Acoustic Study. The zoning administrator may require an acoustic study, at the applicant’s sole cost, for any proposed project that could be exposed to noise levels exceeding the limits in Table 18.110.050.G. When the zoning administrator has determined that there could be cause to make adjustments to the standards, a minimum 24-hour duration noise measurement shall be conducted. The noise measurements shall collect data utilizing noise metrics that are consistent with the noise limits presented in Table 18.110.050.G; e.g., Lmax (0 minutes), L02 (1 minute), L08 (5 minutes), L25 (15 minutes) and L50 (30 minutes). An arithmetic average of these ambient noise levels during the three quietest hours shall be made to demonstrate that the ambient noise levels are regularly 10 or more decibels below the respective noise standards. Similarly, an arithmetic average of ambient noise levels during the three loudest hours should be made to demonstrate that ambient noise levels regularly exceed the noise standards.
I. Noise Attenuation Measures. Any project subject to the acoustic study requirements of subsection (H) of this section may be required as a condition of approval to incorporate noise attenuation measures deemed necessary to ensure that noise standards are not exceeded.
1. New noise-sensitive uses (e.g., schools, hospitals, churches, and residences) shall incorporate noise attenuation measures to achieve and maintain an interior noise level of 45 dBA.
2. Noise attenuation measures identified in an acoustic study shall be incorporated into the project to reduce noise impacts to satisfactory levels.
3. Emphasis shall be placed upon site planning and project design measures. The use of noise barriers shall be considered and may be required only after all feasible design-related noise measures have been incorporated into the project. [Ord. 14-12 § 1; Res. 14-36 § 408.05.]