HomeMy WebLinkAboutRESOLUTION 09-45RESOLUTION 09-45
A RESOLUTION OF THE BUTTE COUNTY PLANNING COMMISSION
RECOMMENDING APPROVAL OF
ZONING CODE AMENDMENT ZCA09-0002
RESIDENTIAL GENERATOR NOISE
WHEREAS, on December 16, 2008 the. Board. of Supervisors directed the
Director of Development Services to prepare an ordinance providing standards limiting
the noise produced by the operation of residential generators, in order to protect the
health, safety, and well being of Butte County residents and visitors; and
WHEREAS, on June 23, 2009 the Board of Supervisors confirmed 55 decibels as
an appropriate limitation for noise produced by the operation of residential generators;
and
WHEREAS, the Planning Commission has considered Zoning Code Amendment
ZCA09-0002 Residential Generator Noise, which provides standards for the operation
and, where needed, enclosure of residential generators in order to meet this noise
limitation; in accordance with Chapter 24, Zoning, of the Butte County Code; and
WHEREAS, Zoning Code Amendment ZCA09-0002 Residential Generator
Noise is exempt from review -under the California Environmental Quality Act, pursuant to
Section 15308 Action by Regulatory Agencies for Protection of the Environment, as an
action to assure the peaceable and safe enjoyment and use of property without the noise
produced by the operation of residential generators; and
WHEREAS, a duly notified public hearing was held on September 24, 2009; and
WHEREAS, the Planning Commission has considered direction from the Board
of Supervisors, public comments 'regarding the proposed Zoning Code Amendment
ZCA09-0002 Residential Generator Noise, and a report from the Planning Division:
NOW THEREFORE, BE IT RESOLVED, that the Planning Commission recommends
that the Board of Supervisors adopt Zoning Code Amendment ZCA09-0002
Residential Generator Noise, with the finding that the zoning code amendment is
consistent with the.General Plan in:
I. Providing for the health, safety and well being of the County's present
and future residents, ,by setting forth standards for the proper operation
and, where needed, enclosure of residential generators; and
II. Contributing to the maintenance of an acceptable noise environment in
all areas of the County, by setting. a standard limiting the noise
produced by residential generators.
Butte County Department of Development Services
TIM SNELLINGS, DIRECTOR I PETE CALARCO, ASSISTANT DIRECTOR
7 County Center Drive
Oroville, CA 95965
(530) 538-7601 Telephone
(530) 538-7785 Facsimile
www.buttecou nty.neVdds
www.buttegeneralplan.net
ADMINISTRATION * BUILDING * PLANNING
MEMORANDUM.
TO: Butte County Board' of Supervisors
FROM: Tim Snellings,.Director
SUBJECT: Additional Materials for the October 27, 2009 Meeting regarding ZCA09-
0001.(Outdoor Lighting in Residential, Areas) and ZCA09-0002 (Residential
Generator Noise)
DATE: October 20 2009
The following finalized materials are attached for your consideration during review of the above
zoning code amendments:
1. Signed Planning Commission Resolution PC 09-44, recommending approval of Zoning
Code Amendment ZCA09-0001 - Outdoor Lighting in Residential Areas
2. Signed Planning Commission Resolution PC 09-45, recommending approval of Zoning
Code Amendment ZCA09-0002 - Residential Generator Noise
3. CD containing audio files of the Planning Commission September, 24, 2009 hearings for
these two zoning code amendments.
Please feel free to contact me at tsnellings a.buttecounty.net or (530) 538-6821, or Principal
Planner Claudia Stuart at (530) 538-7604 or cstuart-buttecounty.net with any questions or for
further information. Thank you.
:7
RESOLUTION 09-44
A RESOLUTION OF THE BUTTE COUNTY PLANNING COMMISSION
RECOMMENDING APPROVAL OF
ZONING CODE AMENDMENT ZCA09-0001
OUTDOOR LIGHTING IN RESIDENTIAL AREAS
WHEREAS, on December 16, 2008 the Board of Supervisors directed the
Director of Development Services to prepare an ordinance providing standards limiting
light trespass and glare in residential areas, in order to protect the health, safety, and well
being of Butte County residents and visitors; and
WHEREAS, on June 23, 2009 the Board of Supervisors confirmed three months
as a reasonable amortization period for non -conforming lighting requiring only re-
direction to be brought into conformance with the proposed zoning code amendment; and
six months as a reasonable amortization period for all other non -conforming lighting; and
WHEREAS, the Planning Commission has considered Zoning Code Amendment
ZCA09-0001 Outdoor Lighting in Residential Areas, which provides standards for the
design and location of outdoor lighting in residential areas in order to limit light trespass
and glare; in accordance with Chapter 24, Zoning, of the Butte County Code; and
• WHEREAS, Zoning Code Amendment ZCA09-0001 Outdoor Lighting in
Residential Areas is exempt from review under the California Environmental Quality
Act, pursuant to Section 15308 Action by Regulatory Agencies for Protection of the
Environment, as an action to assure the peaceable and safe enjoyment and use of property
without the direct light and glare caused by light trespass; and
WHEREAS, a duly notified public hearing was held on September 24, 2009; and
WHEREAS, the Planning Commission has considered direction from the Board
of Supervisors, public comments regarding the proposed Zoning Code Amendment
ZCA09-0001 Outdoor Lighting in Residential Areas, and a report from the Planning
Division:
NOW THEREFORE,, BE IT RESOLVED, that the Planning Commission recommends
that the Board of Supervisors adopt Zoning Code Amendment ZCA09-0001
Outdoor Lighting in Residential Areas, with the finding that the zoning code
amendment is consistent with the General Plan in providing for the health, safety
and well being of the County's present and future residents, by setting forth
standards for the proper design and location of outdoor lighting in residential
areas, in order to limit light trespass and glare.
•
10
DULY PASSED :AND ADOPTI✓D' this 24th: day of September,1'2009, by the following;
, _ . .
AYES Ivlo9re,.,Nelson, Wilson,,iVlarm
NOES None
AR, RT
lollBecker` ;
ABSTAIN: `None7: -: r,.
fernan, Mar 'CE1air
'Planning Comm�ss�on
C oun ywdEBL,tte, State of>'Californ'ia v
Chuck Th�stlethwattc, Secretary -.
Planning Gomrnission
s
County, ofxButte, State of California:.
I
11
•
RESOLUTION 09-45
A RESOLUTION OF THE BUTTE COUNTY PLANNING COMMISSION
RECOMMENDING APPROVAL OF
ZONING CODE AMENDMENT ZCA09-0002
RESIDENTIAL GENERATOR NOISE
WHEREAS, on December 16, 2008 the Board of Supervisors directed the
Director of Development Services to prepare an ordinance providing standards limiting
the noise produced by the operation of residential generators, in order to protect the
health, safety, and well being of Butte County residents and visitors; and
WHEREAS, on June 23, 2009 the Board of Supervisors confirmed 55 decibels as
an appropriate limitation for noise produced by the operation of residential generators;
and
WHEREAS, the Planning Commission has considered Zoning Code Amendment
ZCA09-0002 Residential Generator; Noise, which provides standards Ifor the operation
and, where needed, enclosure of residential generators in order to meet this noise
limitation; in accordance with Chapter 24, Zoning, of the Butte County Code; and
WHEREAS, Zoning. Code Amendment ZCA09-0002 Residential Generator
Noise is exempt from review under the California Environmental Quality Act, pursuant to
• Section 15308 Action. by Regulatory Agencies for Protection of the Environment, as an
action to assure the peaceable and safe enjoyment and use of property without the noise
produced by the operation of residential generators; and
WHEREAS, a duly notified public hearing was held on September 24, 2009; and
WHEREAS, the Planning Commission has considered direction from the Board
of Supervisors, public comments .regarding the proposed Zoning Code Amendment
ZCA09-0002 Residential Generator Noise, and a report from the Planning Division:
NOW THEREFORE, BE IT RESOLVED, that the Planning Commission recommends
that the .Board of Supervisors adopt Zoning Code Amendment ZCA09-0002
Residential Generator Noise, with the finding that the zoning code amendment is
consistent with the General Plan in;
I. Providing for the health, safety and well being of the County's present
and future residents, by setting forth standards for the proper operation
and, where needed, enclosure of residential generators; and
Il. Contributing, to the maintenance of an acceptable noise environment in
all areas of the County, by setting a standard limiting the noise
produced by residential generators.
•
10
el
c:
BE 1T HER. , Commission.. rec.ommen&lo,,'t.h&,
Board ,por ip
.County GeneralrPlan 2U3U process;; -
DULY PASSED
s
$gmm*oy-v r%6 wl
.AYES Moore, Nelson,. V�ilson,Ivlari=n
ALOS 8,
ABSTAIN';M
Fernando Chair:
fib -
;PlanningC 6iii , gibti
*County of Butte; State of California
ATT
Chuck Istet wal'te"-8
ecmtary
Planning Commission:
County 4'.8p Gal' fornia
pj'
!, 1
11
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA - OCTOBER 27, 2009
10:20 A.M. 5.03 * Public Hearing - Zoning Code Amendment (ZCA09-0002) -
Residential Generator Noise - consideration of an
ordinance establishing standards for noise from
residential generators. The standards would apply to
the operation of residential generators in all areas of
the unincorporated portion of Butte County outside of
•the area of applicability for Standards for Limited
Density Owner -Built Rural Dwellings. The proposed
ordinance requires that noise produced by residential
generators shall not exceed 55 decibels at or outside
the originating property line. The proposed ordinance
would be enforced through the County's Code Enforcement
Process action requested - FIND THE PROPOSED ZONING
CODE AMENDMENT EXEMPT FROM.ENVIRONMENTAL REVIEW UNDER
CEQA PURSUANT TO SECTION 15308 OF THE CEQA GUIDELINES;
AND ADOPT ORDINANCE AND AUTHORIZE.THE CHAIR TO SIGN.
10:40 A.M. 5.04 * Public Hearing - Zoning Code Amendment (ZCA09-0001) -
Outdoor Lighting in Residential Areas - consideration
of an ordinance establishing standards for outdoor
lighting in order to prevent direct light from shining
onto adjoining properties. The standards would apply
to the following zones: Agricultural Residential;
Agricultural Suburban -Residential; Foothill
Recreational; Mountain or Recreation Subdivisions -
Residential; Residential; Residential Nonconforming;
Residential -Mobile Home; Suburban Residential; Timber
Mountain; and Unclassified. The proposed ordinance
requires that .all new outdoor lighting conform to the
standards and requires all existing outdoor lighting be
brought into conformity with standards within three to
six months -after adoption of the ordinance. The
proposed ordinance would be enforced through the
County's -Code Enforcement Process - action requested -
FIND THE PROPOSED ZONING CODE AMENDMENT EXEMPT FROM
ENVIRONMENTAL REVIEW UNDER CEQA PURSUANT TO SECTION
15308 OF THE CEQA GUIDELINES; AND ADOPT ORDINANCE AND
AUTHORIZE THE CHAIR TO SIGN.
PAGE 13 OCTOBER 27, 2009
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA - OCTOBER 27, 2009
5.00 PUBLIc HEARINGS AND TIMED ITEMS
9:45 A.M. 5.01 * Timed Item - A Matter on Which a Public Hearing Has
Been Held and Closed - On July 21, 2009 the Board of
Supervisors heard an appeal of Planning Commission's
Denial of'Certificate of Correction application COR07-
0002 to remove a note on Lot 28 of the Sierra
Foothills #2 Subdivision map, Zinfandel Drive, recorded
February 6, 1986 in Book 100, Pages 83 and 84. The
Board directed staff to analyze the comments and
materials submitted during public hearing and to
provide a recommendation. This item was included on
the August 25, 2009 Board of Supervisors agenda, but at
the request of the applicant, the Board continued the
matter closed to October 27, 2009 to ,allow the
applicant time to review the agenda report and
resolution. Staff recommends denial of this appeal -
action requested - ADOPT A RESOLUTION WITH FINDINGS
DENYING THE APPEAL. (Department of Development
Services)
10:00 A.M. 5.02 * Public Hearing - Appeal of Planning Commission's
Condition of Approval for Use Permit UP07-0007 -
consideration of an appeal to modify Condition of
Approval #20 by removing the requirement to construct
a curb, gutter and sidewalk along the Railroad Avenue
frontage of the project. The project is located east
of Railroad Avenue, 0.14 -miles south of the Railroad
Avenue and Kusel Road intersection, near the city of
Oroville (APN 078-030-013). Staff recommends denial of
the appeal - action requested - ADOPT 'RESOLUTION
DENYING THE APPEAL AND UPHOLDING THE PLANNING
COMMISSION'S CONDITION OF APPROVAL #20. '
PAGE 12 OCTOBER 27, 2009
Iml
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Y LC t 4 C1l(4-t24 eo C,
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S�1 i°C-Go r1,�
-BUTTE�COUNTYPLANNING COMMISSION
AGENDA REPORT
September 24, 2009
Applicant:
'County of Butte Location:
Various
-File #:
ZCA09-0002 Residential
Parcel Size:.
Various
Generator Noise
Request:-
Atnend the, zoning ordinance to Supervisor
All
more effectively implement Districts:
Policies Lb- 1.l.a, LU 6. La, and
N-1' of the General Plan.
G.P.:
Various Planner:
Claudia Stuart
Principal Planner
(530) 538-7604
-Zoning:.
Various Attachments:
A:
Resolution recommending
approval of Zoning Code
Amendment. ZCA09-0002
-Residential Generator Noise to
the Board of Supervisors
Zone, Date:
N/A B:
Draft ZCA09-0002 Residential
Generator Noise
C:
Staff Report to the Board of
Supervisors dated June 23,
2009
D:
Changes to the June 23, 2009
preliminary draft ordinance
(underline/strikeout version)
■ BUTTE COUNTY PLANNING COMMISSION AGENDA REPORT■
■ September. 24, 2009 ,■ ZCA09-0002 Residential Generator Noise ■
■ Page 1 of 6 ■
1
SUMMARY
The County is proposing a revision to Chapter 24 of the Butte County Code prior to preparation
of a comprehensive zoning code .update as part of the Butte County General Plan 2030 process.
The proposed revision requires that noise produced by residential generators not exceed 55
decibels at or outside the originating property line. Residential generators not meeting this
standard could be retired, retrofitted, repaired, replaced, or enclosed in a sound reduction
enclosure. Associated guidelines :for the construction of sound -reduction enclosures would be
published by the Department of Development Services. Enforcement would follow procedures in
Chapter 41 (Code Enforcement Policies and Procedures) of the Butte County Code.
RECOMMENDATION
Staff recommends adoption of the resolution recommending approval of Zoning Code
Amendment ZCA09-0002 Residential Generator Noise (Attachment A) to the Board of
Supervisors.
PROJECT DESCRIPTION
Background
Noise is defined as a sound or series of sounds that are considered to be invasive, irritating,
objectionable and/or disruptive to the quality of daily life. Noise varies in its range, source and
volume and can originate from individual incidents such as lawnmowers, to sporadic
disturbances, such as car horns or train whistles, to more constant irritants, such as traffic along
major arterials. Noise is a concern throughout Butte County, but especially in rural areas and in
the vicinity of noise -sensitive uses such as residences, schools, and churches.
In the fall of 2008, the Department of Development Services received reports of persistent
generator noise from residents in the Palermo-Honcut area. The reported noise originated from
residential generators operating at a distance of several thousand feet from the complainants'
homes. The reports noted that the generator noise disturbed the residents' ability to sleep,
reduced their ability to enjoy the use of their properties, and potentially affected local livestock
and wildlife as well as human health and property values. Staff conducted a site visit on February
4, 2009 and found the generator use persisting at that time. The properties from which the noise
originates, and the affected properties, are located in the GOL Grazing and Open Lands land use
designation, and are zoned A-5 (Agricultural, 5 acre minimum) and A-40 (Agricultural, 40 acre
minimum).
i
The Butte County General Plan Noise Element identifies 60 decibels (dB) as a , maximum
acceptable noise level for meeting indoor noise requirements. Butte County does not currently
have a noise ordinance. The current Butte County code does include several noise: standards:
Section 24-275 (Recycling facilities) requires that noise generated by recycling, collection, and
processing facilities shall not exceed 60 decibels as measured at the property line of'residential
■ BUTTE COUNTY PLANNING COMNIISSION AGENDA REPORT■
■ September 24, 2009 ■ ZCA09-0002 Residential Generator Noise ■
■ Page 2 of 6 ■
2
property, and shall not otherwise exceed , 70 decibels. Standards for the C -C Community
Commercial and N -C .Neighborhood Commercial zones, limit noise generation to 60 decibels at
the property line for 6 hours per, day, with no noise exceeding 80 decibels. However, none of
these standards address the reported instance of noise originating from and affecting parcels
designated and zoned for -agriculture, but also serving as residences.
Discussion
The proposed zoning code amendment (Attachment B) was prepared after direction from the
Board of Supervisors on December 16, 2008. The Board directed staff to develop standards to
limit the noise produced .by generators used to support residential uses. Staff has sought to
address the identified issues while limiting the breadth and complexity of the ordinance, pending
completion of a comprehensive zoning code update as part of Butte County General Plan 2030.
In preparing the zoning code amendment, staff reviewed ordinances from a number of
jurisdictions in California (e.g., Sacramento County, San Luis Obispo County), Florida, New
York and several other states.
The proposed zoning code amendment establishes a maximum allowable noise level for
residential generators, and. provides for the publication of sample construction specifications and
guidance to assist operators who need to enclose their equipment in order to meet that standard.
Based on staff research, staff recommends 55 decibels (dB) as the maximum allowable noise
.level. Sound levels would be measured at a location along or outside the originating property
line. Operators of residential generators not meeting the noise standard could retire or replace the
generator, retrofit it, or enclose it in a sound -reducing structure. After the effective date of the
ordinance, enforcement would follow procedures in Chapter 41 (Code Enforcement Policies and
Procedures) of the Butte County Code. (See Attachment. C for the June 23, 2009 staff report to
the Board of Supervisors, including draft guidelines for the construction of sound -reduction
enclosures.)
At its June 23, 2009 meeting, the Board of Supervisors confirmed the proposed limit of 55 dB
for noise produced by.residential generators, as.well as the general provisions of a preliminary
draft of the proposed amendment (Attachment Q. Additional refinements have been made to
the draft ordinance after further staff review and in coordination with County Counsel. These
changes are shown in underline (additions) and strikeout (deletions) in Attachment D.
CONFORMANCE WITH THE GENERAL PLAN
Land Use Element
The Land Use Element (adopted 1979, multiple revisions through 2009) of the existing Butte
County General Plan sets forth the County's direction regarding land use and development,
including the following policy:
I. I. a. Provide for the health, safety. and well-being of the County's present and future
residents.
■ BUTTE COUNTY PLANNING COMMISSION AGENDA REPORT■
■.September 24, 2009 ■ ZCA09-0002 Residential Generator Noise ■
■ Page 3 of 6 ■ 3
0
The proposed zoning code amendment is consistent with Policy LU-l.l.a. in providing minimum
requirements for the operation of residential :generators throughout the County; in order to
protect the health, property, andvell being of Butte County residents and visitors.
The Land Use Element further describes measures that can be taken to minimize objectionable
uses, specifically by location and design measures, and sets forth relevant direction in Policy
6. l .a..
The relatively low intensity of land use in much of the County has created a generally
safe and pleasant livingand working environment. Many types of land use, especially
some commercial and industrial activities, can be detrimental to the health and safety or
nearby residents and workers. However, the blighting effects of many "objectionable"
uses can be minimized by requiring suitable locations and mitigating design measures.
6.1. a. Maintain public health and safety by requiring proper location and design for uses
with offensive odors, dust, smoke, light, traffic, vibration, explosives, pollutants, insects
and similar blighting influences.
The proposed zoning code amendment is consistent with Policy LU -6.1.a., in providing
standards for the operation and, where needed, enclosure of residential generators, in order to
protect the health, property, and well being of residents and visitors from persistent noise.
Noise Element
The Noise Element (adopted 1977) of the County's existing General Plan is intended to identify
and appraise noise problems in the community, and to include implementation measures and
possible solutions that address existing and foreseeable noise problems. It identifies the
disturbing effects of noise, such as speech or sleep interference, irritation, and loss of privacy.
The Noise Element notes that noise generation can be abated by controls on the source, such as
insulating barriers between sound generators and receptors. However, as acknowledged in the
document:
The Noise Element evaluation primarily addresses a maximum acceptable', community
noise level of 60 dB to provide a suitable noise environment inside buildings. Since
outdoor living is a major activity is a major activity in Butte County, this standard may
not be low enough to permit unhindered speech communications outdoors. Speech
communication is severely hindered when background noise levels rise to 50-55 dBA.
Although the Noise Element does not provide specific standards for stationary noise sources in
residential areas, it includes the following finding and policy:
Finding - 1
Objectionable noise from transportation facilities and stationary sources can have a
significant impact on public health and welfare.
■ BUTTE COUNTY PLANNING COMNIISSION AGENDA REPORT■
■ September 24, 2009 ■ ZCA09-0002 Residential Generator Noise ■
■Page 4of6■
4
Policy - 1
Endeavor to maintain an acceptable noise environment in all areas of the County.
The proposed zoning code amendment is consistent with this policy, in establishing an
acceptable noise standard for residential generator use in order to limit _objectionable noise from
these stationary sources.
RELATIONSHIP TO BUTTE COUNTY GENERAL PLAN 2030
A comprehensive update o= the Butte -County General Plan and zoning code, called Butte County
General Plan 2030, is currently underway. The draft Butte County General Plan 2030 Health and
Safety Element contains th,following goal and policy:
Goal HS -1 Maintai.i an acceptable noise environment in all areas of the county. (Noise
Element Policy 1)
HS-Pi.8 Noise frog generators .shall be regulated .near existing and future residential
uses.
Staff expects that standard3 pursuant to this policy will be included in the comprehensive zoning
code update being prepared as part of the Butte County General Plan 2030 process. Butte County
General Plan 2030 and the comprehensive update to the zoning code are scheduled for adoption
in September 2010.
PUBLIC -CONTACT AND COMMENTS
Verbal comments supporthtg the proposed zoning code amendment were received at the Board
of Supervisors -meetings on December 16, 2008 and June 23, 2009.
The proposed zoning cod,,- amendment was reviewed with the Users Group on July 29, 2009.
Several participants opposed the draft ordinance, expressing the belief that noise should be
addressed as a civil matter rather than by local ordinance. Comments also noted challenges in
enforcement, including lack of staff or funding resources. However, other participants
acknowledged the potentizl impacts of noise on community well being.
Notice of the Planning Commission public hearing was provided consistent with Section 24-
25.25 (Public hearing for zoning amendments) of the Butte County code.
ENVIRONMENTAL REVIEW
The proposed zoning co.de amendment is exempt from further review under the California
Environmental Quality Act (CEQA) under Section 15308 Action by Regulatory Agencies for
■ BUTTE -COUNTY PLANNING CONMSSION AGENDA REPORT.
■ September 24, 2009 ■ ZCA09-0002 Residential Generator Noise ■
■ Page 5 of 6 ■
5
Protection of the Environment. Class 8 consists of actions taken by regulatory agencies, as
authorized by local ordinance, to assure the maintenance, restoration, enhancement, or protection
of the environment where the regulatory process involves procedures for protection of the
environment. The proposed zoning code amendment is such an action to assure the peaceable
and safe enjoyment and use of property without the noise produced by the operation of
residential generators.
The Planning Commission will be making a recommendation to the Board of Supervisors
regarding the proposed zoning code amendment ZCA09-0002 Residential Generwor Noise. If
the Commission makes a recommendation, staff expects to schedule the Board of Supervisors'
public hearing on October 27, 2009. Oral or written testimony given during the Planning
Commission meeting will be included in the materials for the Board's consideration.
■ BUTTE COUNTY PLANNING CONMSSION AGENDA REPORT■
■ September 24, 2009 ■ ZCA09-0002 Residential Generator Noise ■
■ Page 6 of 6 ■
6
T.f
7
RESOLUTION 09-
A RESOLUTION OF THE BUTTE COUNTY PLANNING COMMISSION
RECOMMENDING APPROVAL OF
ZONING CODE AMENDMENT ZCA09-0002
RESIDENTIAL GENERATOR NOISE
WHEREAS, on December 16, 2008 the Board of Supervisors directed the
Director of Development Services to prepare an ordinance providing standards limiting
the noise produced by the operation of residential generators, in order to protect the
health, safety, and well being of Butte County residents and visitors; and
WHEREAS, on June -23, 2009 the Board of Supervisors confirmed 55 decibels as
an appropriate limitation for noise produced by the operation of residential generators;
and
WHEREAS, the Planning Commission has considered Zoning Code Amendment
ZCA09-0002 Residential Generator Noise, which provides standards for the operation
and, where needed, enclosure of residential generators in order to meet this noise
limitation; in accordance with Chapter 24, Zoning, of the Butte County Code; and
WHEREAS, Zoning Code Amendment ZCA09-0002 Residential Generator
Noise is exempt from review under the California Environmental Quality Act, pursuant to
Section 15308 Action by Regulatory Agencies for Protection of the Environment, as an
action to assure the peaceable and safe enjoyment and use of property without the noise
produced by the operation of residential generators; and
WHEREAS, a duly notified public hearing was held on September 24, 2009; and
WHEREAS, the Planning Commission has considered direction from the Board
of Supervisors, public comments regarding the proposed Zoning Code Amendment
ZCA09-0002 Residential Generator Noise, and a report from the Planning Division:
NOW THEREFORE, BE IT RESOLVED, that the Planning Commission recommends
that the Board of Supervisors adopt Zoning Code Amendment ZCA09-0002
Residential Generator Noise, with the finding that the zoning code amendment is
consistent with the General Plan in:
I. Providing for the health, safety and well being of the County ';s present
and future residents, by setting forth standards for the proper operation
and, where needed, enclosure of residential .generators; and
II. Contributing to the maintenance of an acceptable noise environment in
all areas of. the County, by setting a standard limiting the noise
produced by residential generators.
r;�
i
,D.ULY PASSED ANDS ADOPTED this 24th day of September, 2009, by :the following
s
ATTACHMENT B
10
1 Ordinance No.
2 .
3 AN ORDINANCE ADDING SECTION 24-242, °ENTITLED RESIDENTIAL
4 GENERATOR NOISE, TO ARTICLE W OY CHAPTER 24 OF THE BUTTE
5 COUNTY CODE
6
7 The Board of Supervisors of the County. of Butte ordains as follows:
8 Section 1. Section 24-242 is added to`Article IV; entitled"General Development
9 Regulations" of Chapter 24, entitled "Zoning"; of the Butte County Code. to read as
10 follows:
11 24-242 Residential Generator Noise
,12 .(a) Purpose. The purpose of this section is to. provide minimum requirements for the
13 'operation of residential generators, in order to reduce noise levels and protect the health,.
14 property, and well being of Butte County.residents and visitors.
15 (b) Definitions. The definition of terms in this section shall be as follows: -
16 (1) Agriculture. The use of land for commercial agricultural purposes as defined in
17 Section 24-305. -
18 (2) Decibel. The logarithmic unit of measurement that quantifies sound levels.
19 (3) Emergency. Disaster or extreme peril to'the safety of persons, the environment, and .
20 property caused by such conditions d`s fire, flood, storm, epidemic, riot, earthquake, or
21 hazardous materials.
22 (4) Noise level. The sound pressure level in decibels obtained by using a sound level
23 meter.
W .0
-24 (5) Residential :generator. A -machine that produces electricity to support residential uses,
25 including supplying power directly to a residence or for incidental residential activities.
26 (c) Applicability. This section shall apply to the operation of residential .generators. This
27 section does not apply to the area of applicability for Standards for Limited Density
28 Owner -Built Rural Dwellings. Allowable noise levels for Limited Density Owner -Built
29 Rural Dwellings are defined under Article VI, Chapter 26 of the Butte County Code.
30 (d) Standards.
31 (1) Noise levels. Residential generators shall not produce more than fifty-five (55)
32 decibels at any point along or, outside the property line.
33 (2) Installation. Permanent generators shall be permanently secured on a minimum 3
34 and 1/2 inch thick concrete slab extending a minimum of two feet beyond the generator on
35 all sides, or shall be anchored,as required in the manufacturer's installation instructions to
36 prevent vibration.
37 (3) Compliance with Noise Standard. Residential generators not meeting the noise
38 standard shall be brought into compliance in any of the following ways:
39 a. Cessation of operation;
40 b. Retrofitting of the generator with a manufacturer -approved muffler or exhaust silencer;
41 c. Repair of the generator;
42 d. Replacement of the generator with a conforming generator; or
43 e. Enclosure of the generator in conformance with subsection (d) (4) of this section.
44 (4) Enclosure. If needed to comply with the maximum decibel level, generators shall be
45 enclosed in a sound reduction enclosure approved by the Building Official. This structure
46 shall be fully enclosed; and may be constructed consistent with published County
12
47 guidelines for -generator noise reduction, or may be a -commercially manufactured
48 enclosure. Generator,enclosures shall reduce noise to the level required by this.section.
49 Enclosures shallbe.constructed to meet current California.Building Code standards, shall
50 provide a minimum of thirty�(30) inches of interior structural clearance to allow access on
51 all sides of the, generator; and shaft -be, adequately ventilated and vented. The Director of
52 Development Services shall.publish and maintain guidelines for the.construction of
53 effective generator noise reduction enclosures.
54 , ''(e) Exceptions. The standards of this'section are not applicable. to.,generator noise from
55 the following sources:
56 ,(1) The use of any generator related to or connected with an emergency, in order to
57 protect life or property; or during.a temporary power outage; and
58 (2) The operation -of any, generator for commercial agricultural use.
59 (f) Noise level measurement. The County.may conduct field testing to verify noise levels;
60 and/or the County may require the.operator to conducf field testing. If the operator is
61 required to verify noise levels, a test report,showing compliance shall be provided by the
62 operator and submitted to the Director of Development Services at the operator's
63 expense. For the purpose of evaluating conformance with the standards of this section,
64 noise levels shall be measured as follows:
65 (1) Use of meter. Any noise measurement made-pursuant.to this -section shall be made
66 with a sound level meter calibrated and operated according to the manufacturer's
67 instructions; and
`W
68 (2) Meter location. Exterior noise levels. shall be measured at any point along or outside
69 the property line. Where practical, the meter shall be positioned five feet above the
70 ground and away from reflective surfaces.
71 (g) Enforcement. Any person who violates any of the provisions of this section shall be
72 subject to the provisions of Chapter 41, entitled "Code Enforcement Policies and;
73 Procedures", of this code.
74 Section 2. Severability. If any provision of this Ordinance or the application thereof
75 to any person or circumstances is for any reason held to be invalid by a court of
76 competent jurisdiction, such provision shall be deemed severable, and the invalidity
77 thereof shall not affect the remaining provisions or other applications of the
78 Ordinance which can be given effect without the invalid provision or application
79 thereof.
80 Section 3. Effective Date and Publication. This Ordinance shall take effect thirty
81 (30) days after the date of its passage. The Clerk of the Board of Supervisors is
82 authorized and directed to publish this ordinance before the expiration of fifteen (15)
83 days after its passage. This Ordinance shall be published once, with the names of the
84 members of the Board of Supervisors voting for and against it, in the
85 a newspaper of generalcirculation published in the County of
i
86 Butte, State of California.
87 PASSED AND ADOPTED by the Board of Supervisors of the County :of
88 Butte, State of California, on the day of , 2009, by the
89 following vote:
90 AYES:
14
J
91
NOES:
92
ABSENT:
93
NOT VOTING:
94
95
Bill Connelly, Chair of the
96
Butte County Board of Supervisors
97
98
ATTEST:,
99
Gregory G. Iturria
100
Interim Chief Administrative Officer
101
and Clerk of the -Board
102
103
By .
15
ATTACHMENT C
16
• 0
Butte County Department:of Development Services
'TIM SNELLINGS, DIRECTOR I PETE CALARCO, ASSISTANT DIRECTOR
7 County Center Drive
Oroville, CA 95965
(530) 538-7601 Telephone
(530)'538-7785 Facsimile
www.buttecounty.net/dds
www.buftegeneralplan.net
ADMINISTRATION *'BUILDING * PLANNING
June 23, 2009
Butte County Board of Supervisors
25 County Center. Drive
,Oroville, CA 95965
SUBJECT: DRAFT ORDINANCE - RESIDENTIAL GENERATOR NOISE
Recommendation
Staff requests that the Board -of Supervisors:
1. Provide staff with direction regarding the appropriate allowable noise, standard for, residential
generators; and
2. Review the proposed ordinance and provide additional comments as desired.
Proiect Summary
Pursuant to the Board's direction on December 16, 2008 staff has prepared a draft ordinance
(Attachment A) to address noise produced by residential generators.
Background -
In the fall of 2008, the Department of Development Services received reports of persistent
generator noise from residents in the Palermo-Honcut area. The reported noise originates from
residential generators operating at a distance of several thousand feet from the complainants'
homes. The reports noted that the generator noise disturbed the residents' ability to sleep, reduced
their ability to enjoy the use.of their properties,. and potentially affected local livestock and wildlife
as well as human health and property values. Staff conducted a site visit on February 4, 2009 and
found the generator use persisting at that time. The properties from which the noise originates, and
the affected properties, are located in the GOL Grazing and .Open Lands land use designation, and
are zoned A-5 (Agricultural, 5 acre minimum) and A-40 (Agricultural, 40 acre minimum).
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
■June 23, 2009 ■Residential Generator Noise■
1 of 17
r 0
The Butte County General Plan Noise Element identifies 60 decibels {dB) as a maximum
acceptable noise level for meeting indoor noise requirements. However, it acknowledges that this
noise level may be too high to control effects on human use of outdoor areas.! The 'State of
California General Plan Guidelines establish 60 dB as normally acceptable to residential land uses.
Butte County does not currently -have a noise ordinance. The current Butte County code does
include several noise standards: Section 24-275 (Recycling facilities) requires that noise generated
by recycling, collection, and processing facilities shall not exceed 60 decibels as measured at the
property line of residential property, and shall not otherwise exceed 70 decibels. Standards for the
C -C Community Commercial and N -C Neighborhood Commercial zones limit noise'' generation to
60 decibels at the property line for 6 hours per day, with no noise exceeding 80 decibels. However,
none of these standards address the reported instance of offensive noise originating from and
affecting parcels designated and zoned for agriculture, but also serving as residences.
On December 16, 2008 the Board directed staff to identify options for preparing an interim noise
ordinance that would address such instances of generator noise. Staff has sought to address the
identified issues while limiting the breadth and complexity of the ordinance, pending, completion of
a comprehensive noise ordinance pursuant to adoption of Butte County General Plan 2030. In
preparing the interim ordinance, staff reviewed ordinances from a number of jurisdictions in
California (e.g., Sacramento County, San Luis Obispo County), Florida, New York and several
other states.
Discussion
The decibel (dB) scale is an international standard for measuring sound pressure` levels. Each
three dB increase means that sound energy is doubled, while each 10 dB increase corresponds to
sound energy increased by a factor of 10. Sound levels further vary depending on distance from
the noise source. Typical sound measurements indicate that sound levels 120 dB and above are
painful or injurious (jet plane takeoff at 200 feet); levels above 85 dB are extremely loud
(lawnmower); and levels above 60 dB are loud (for example, 70 dB is the sound level of a vacuum
at 10 feet). Fifty (50) to 60 dB is the sound level of normal conversation; 50 dB an average
residence; and 40 dB a quiet room or soft whisper. Human perception of sound pressure levels can
be more closely simulated by measurement using the "A" weighted scale. Changes of five dB(A)
are perceived as quite noticeable, and a 10 dB(A) change is perceived as twice as loud.
Expectations for residential tranquility in rural areas can lead rural jurisdictions to adopt more
stringent noise standards than in more urbanized areas. Allowable noise levels may be lower at
night, reflecting stronger expectations for quiet during evening and sleep hours. For example, San
Luis Obispo County limits allowable sound levels affecting residential uses to 50 dB during the day
and 45 dB during the night (Table 1).
Table 1. Sample County Noise Limits
Jurisdiction
Daytime
Nighttime
Sacramento Count 1976
55 dB(A)* 7 a.m. —10 .m.
50 dB(A) 10 p.m. - 7 a.m.
San Luis Obispo Count 1992
50 d6 7 a.m. to 10 .m.
45 d6 10 p.m. — 7 a.m.
Montgomery County, MD
65 dBA
55 dBA
Jefferson County, WV
60 dB(A)
50 dB A
dB(A) (or dBA) denotes the use of weighting filters, used to approximate the human ear response. The measurement
is still in dB.
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
•June 23, 2009 ■Residential Generator Noise■ ,� $
2 of 4
The draft interim ordinance�establishes a maximum allowable noise level for residential generators,
and provides construction standards and guidance ---to assist operators who need to enclose their
machines in order to meet that standard. A single maximum allowable noise level is proposed
rather than separate day/night standards. The use of a single standard is consistent with existing
noise limitations in the Butte County Code, and will simplify noise measurement and enforcement.
Based on the research and other information outlined above, staff recommends 55 dB as the
maximum allowable noise level for,unenclosed residential generators in the County, including its
rural areas. Sound levels would be measured at a location along or outside the property line (as
appropriate to account for the effects of topography or built features) while the generator is
operated at full load.
Alternately, should the Board of Supervisors direct preparation of separate day/night standards,
staff recommends 60 dB for daytime hours and 50 or 55 dB for nighttime hours. In this case, staff
also requests confirmation of the appropriate hours forimplementation of day/night standards
(potentially 7 a.m. to 7 or 10 p.m. for daytime; and 7 or 10 p.m. to 7 a.m. for nighttime).
Operators of generators not meeting the noise standard could retire or replace the generator,
retrofit it, or enclose it in a sound -reducing structure such that the noise standard is met.
Enclosures could be purchased from the generator manufacturer, or constructed by the operator to
address their generator's specific noise -level and other operational characteristics. Safety-related
standards for all enclosures are incorporated into the proposed ordinance. Further guidance for the
construction of noise -reducing enclosures, including sample specifications, would be published and
updated as needed by the. Department of Development Services (Attachment B).
After the effective date of the ordinance, enforcement would follow procedures in Chapter 41
(Code Enforcement Policies and Procedures). of the Butte County Code. In cases where
complaints are received, violators would be notified of the violation, the. specified action necessary
to correct the violation, and the period :of time allowed for correction. Operators of residential
generators in violation of allowable noise levels would have the option of retiring, replacing, or
enclosing their generators. Violations continued in disregard of notice .would be subject to fines
and/or other remedies under the Butte County Code. In order to effectively enforce the ordinance,
the County would need to make staff available as necessary to investigate complaints.
Relationship to Butte County General Plan 2030
A comprehensive update of the Butte County General Plan and zoning code, called Butte County
General Plan 2030, is currently underway. Establishment of a noise ordinance has been included
as a final policy alternative for draft Butte County General Plan 2030. Preparation of the noise
ordinance will take place after adoption of the new General Plan in September 2010. Staff expects
that the noise ordinance will provide standards for allowable noise levels for a variety of land uses,
including noise from residential generators.
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
■June 23, 2009'- Residential Generator Noise■
3of4 ' 19
1
t '�x
is
Requested Action
Provide ditection;to; staff regardln a , ro nate allowable. noise `IeVels for residential generators, ,
and: any other matters pertaining to'tf a ordinance=as. desired _ «.
r ..
Fob further Information regarding the proposed .o.rdinance' please contact:;Pnncipal Planner: Claudia '
Stuart at (530),538 7604 or csj art C—buttecounty- n'et: ,
Sincerely,
._ , 1Yrz .:. ? r x � � � � 5 =° . ;! e 9 "' ♦' _ Y . e} c � .: v# tk,. � x 1
:
<
L - TIm Snellirigs, Dir
Attachmentsl
�A. Draft Ordinance R'Oidenbal Generator1Noise
f'
V. ;Draft Generator Noise: Reduction Enclosure Gwdelines (Department�of D0,etopment.
Services) .
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' t3,UTTE COUNT' BOARD'OF SUPERVISORS AGENDA REPORT t. "
Li,June 23, 2009`■Resloontial,5Generatbr Noise• ;' _ , .' _: "� 7
20
zki .a r ♦
U' x .A?3 l e z, ... ,A t ax Y i w i3 • a
= .. t x : e'.
l
1 Ordinance No.
2
3 AN ORDTNANCE ADDING SECTION `24-242; ENTITLED'RESIDENTIAL
4 'GENERATOR NOISE, TO ARTICLE IV OF 'CHAPTER 24 iOF THE BUTTE
5 COUNTY -CODE
6
A4
7 The Board of Supervisors of,the County of Butte ordains a�s,follows
8 -Section. 1. Section 24242 is.added to Article IV, enti led- eneral 5e0elopment
9 Regulations" of Chapter 24. entitled-;
``Zoning'; of the Butte -County Code xead'as
10 -follows: I � � „E�. � ♦� ��� .
'
11 24-242 Residential Ge nerator Noise
12 (a) Purpose. The purpose of this section sJto pro ekminimurprequirements for the
.z
13 operation of -residential ever=ators ,'in order reduce no se levels and protect the health,
14 property, and wello em -hof Butte County residents and -visitors:
15 (b) Define R The defim on of term ffi- section shall: be as follows:. .
- 16 (1) AgCulture. The u eof landfoo'r$ co mercial agricultural. purposes as defined in
17 Section 24-305
5
.18 (2) Decibel. The logarithmile: unit of measurement that quantifies sound levels.'.
19 (3) Emergency. Disa'. r. or extreme peril to the safety of persons, the environment, and,
20 property caused by such conditionsasfire, flood, storm, epidemic, riot, earthquake, or
21 hazardous`cnaterials.'
22 (4) Full load. The maximum -operational load for which a generator is.designed.
21
i
23 . ...(5) Noise level. The sound, pressure level in decibels obtained by using a sound level
!I
24 meter.
i
25 (6) Residential generator. A machine.that produces electricity to'support residential uses,
26 including supplying power directly to a residence or for incidental residential activities.
27 (c) Applicability. This section shall apply to the operation of residential generators. This
28 section does not apply to the area of applicability for StandardsZodrIN-Limited Density
29 Owner -Built Rural Dwellings. Allowable noise levels for Limi ed*Density Owner -Built
Nag
30 Rural Dwellings are defined under Article VI, Chapter 26 of the BA ounty Code.
31 (d) Standards.
32 (1) Noise levels. Residential •generators shall produceat II load a maximum of fifty-five
33 (55) decibels at any point along or out de6tth„ e property lin x�
34 (2) Installation. Permanent generators shall be perm'a�nently secured on a minimum 3
v
35 and 1/2 inch thick concre el; !extending a nimum of two feet beyond the generator on
36 all sides, or shall lie an bored aksquired in the manufacturer's installation instructions to
37 prevent vibration �,
4
38 (3) Compliance with Noise Stan'�sdar&Residential generators not meeting the noise
it, r1l
39 standard, and which arethe�bject of a complaint, shall achieve compliance in any of the
40 following ways ;i
.i
41 a. Cessation of operon;
�,I l
42 b. Retrofitting of the generator, with a manufacturer -approved muffler or exhaust silencer;
43 c. Repair of the generator;
44 d. Replacement of the generator with a conforming generator; or
45 e. Enclosure of the generator in conformance with subsection (d) (4) of this section.
If
II
22
.46 (4)� Enclosure., Ifneeded. to coniply"With the. inaximIum decibeHevel, generators shall be
47. enclosed in a sound reduction enclosure approved by the Building Official.7his structure
`48 shall be fully enclosed and constructed, consistentwith published, County -guidelines for
49 -generator noise, reduction; or shall be, an-approved-commiercial,ly manufactured enclosure.
50 Generator enclosures shall reduce noise to the -level required by -this section: Enclosures
51 shall be constructed. to. meet current California Building, Code. stars
st9hd' �-.4s, shall provide a
?
.41
52 -minimum of thirty (30)Anches� of interior structural clearante fid"atlow access on All.sides
uvv
generator, and §hall'be:adeq6ately ventilated 'Ndk of r
53, of the tilated-an enn ed. NNA-Ge6tor
7.
C * f
54, 'Development Servic6s:'s-hallpubjish and inaingin guidelirfes for the cons% 0
55 `effect*ivd, generator noise, reduction enclosures:
56 (e) Exceptions. The standards; of thiss&�Uipn,ar6 notapplic!&e to,jenerator'noise from
57 -ithe U16wing sources: M
ta-2,616ted to orco n emergency; `in to
58 (1) The use of any �generdil ec dd, wit,
59 protect liff of prood i%g-Or d—uridgja temporary Plower outage.-
60 (2) The opefatibriv., A any II'Ig_e* ror-Zoijmme Zi [agricultural Use.
61
(f) Noise level measurement JUL feldte ting is 14"vId W verify y noise levels, d test report
62'-- showing co liahce shallbeprovided by the'6perAtor and submitted to the Director of
63 R icesat e operator's
Development S _expense. For the purpose of eva.luating
64 conformance with th standards of this section', noise levels shall be,meagured as follows:
165 (1) Use of meter. Anyhoise measurement easuf6ment made pursuant to this section 'shall b6 made
66 with a sound level meter calibrated and operated according to the manufacturer's
67 instructions; and
23
ji
,i
68 (2) Meter location. Exterior noise levels -shall be measured; at any point along or outside
69 the property line. Where practical, the meter shall be positioned five feet above the
70 ground and away from reflective surfaces.
71 (g) Enforcement. Any person who violates any of the provisions of this ordinance shall.
72 be subject to the provisions of Chapter 41 Code Enforcement Policies and Procedures.
f
73 Section 2. Severability. If any provision of this Ordinance ort,e` pplication thereof
l;
74 to any person or circumstances is for any reason held oto be `n valid by a court of
.i
75 competent jurisdiction, such "provision shall be deemed., rable, and,the invalidity
`�
76 thereof shall not affect the remaining pr�ouisioons or other applications oaf the
77 Ordinance which can be given effect Without the�nuffid provision or application
78 thereof.
79 Section 3. Effective Date and Publication. This1®rdinanc all take effect thirty
80 (30) days after the date", ofttspassage. The Clerk n- _e Boardof Supervisors is
i
81 authorized and directed to publisl} this ordinance before the expiration of fifteen '(I
82 days after its passage. Thi'91%, ane`shal be published once, with the names of the
83 members of the Board of Supe v'sors voting for and against it, in the
u
1 -I'
84< < a newspaper of general circulation published in the County of
i
85 Butte, State of GAG NorniaNCA.
86 PASSED A�1 ' ADOPTED by the Board of Supervisors of the County of
87 Butte, State of California, on the day of 2009, byr!the
„
88 following vote:
89 AYES:
90 NOES:
l 24
i
i
91 ' ABSENT: ;
92 NOT VOTING: �• .
93 ;
'94Bill Connelly,'Chair Of the
95 Butte County"Board of Supervisors
. 96
97 'ATTEST: '
98 Gregory G. Iturria, °
99 Interim Chief AdministrativeOfficer
` 100 • and Clerk of the Board
{
101
1102 By .. .,
• 0
Butte County Department of Development Services
TIM SNELLINGS, DIRECTOR I PETE CALARCO, ASSISTANT DIRECTOR
7 County Center Drive
Oroville, CA 95965
(530) 538-7601 Telephone
(530) 538-7785 Facsimile
www.buffecounty.net/dds
www.buttegeneralplan.net
ADMINISTRATION * BUILDING * PLANNING
RESIDENTIAL GENERAT(
NOISE REDUCTION ENCLOSURE
June 2009 ,'
Butte County requires that residential generators producing so
at the property line be enclosed in a noise reduction:-encI sure
55 dB. Enclosures are not generally required for gene"tors pn
The following information is intended to provide guidance to gE
respect to achieving effective noise condbb-This information is'
should not be construed as an endorse ment:6 , ny product by
are free to choose other construction meth 's or ve
of the Butte County Code and other applicable,codes`zy
The design of any structu
Official. Generator enclos
constructed to meet curre
are listed below. WFiatevE
at the nearest property lin
•44�:Dense materials
Resilient materials
Diss Tilar layers
• Incr ased*air space inwall
Acoust c�,al structural cnateri
Sound-absorbin insulation
• Sealed joints an , dges
• Reduced vibration
• Silenced exhaust
levels of ov6KZ5,decibels (dB)
;h reduces th6�Et rld to below
sjnq lower noise;levels.
owners and operators with
J only as guidance, and
ounty. Generator operators
at meet the requirements
to reduce'ge�,f erator noiWebust be approved by the Building
ie built and prloperly vented for air intake and exhaust, and
d California building codes. Key noise reduction techniques
atures are selected, noise levels must be reduced to 55 dB
partitions
als, lining, and sealants
WALL MATERIALS
In general (for traditional wall materials) the denser and/or thicker the wall, the more it will reduce
noise. If layers are made of different materials and/or thicknesses, sound transmission is further
reduced. Newer, readily available sound -reducing panel materials are designed to reduce
noise without substantially increasing wall thickness. These include manufactured soundboard
or sound barrier wall applications (Homasote Sound Barrier, Quiet Rock), medium -density
fiber board, and fiber cement siding (Nardi board). Alternately, a double layer of gypsum
may be used for interior walls to help dampen sound.
Page 1 of 4 26
STUDS AND WALL SYSTEMS
The interior and exterior of the structure may be separated using staggered studs or a
double wood stud partition. Or, metal studs may be used. Sound barrier wall panels can be
attached directly to the studs and covered with gypsum board which is fixed to the sound barrier
but not to the studs. This will help reduce sound transmission through the structure. Padding
tape can further help reduce sound transmission through the studs.
Sound -1e icing linings and nsulation hblude mineral wool; mass -loaded vinyl; and acoustical
panels, matsforr soundproofing composites. Acoustical blankets are made from sound -
absorbing materials and can reduce noise. Acoustical blankets can be placed in the wall space or
can be effective �inightweigh#portable construction.
EXHAUST SYSTEM -,r
Much of a generator's noise comes out of its exhaust system. However, mufflers must be
compatible with the g nerator system and properly vented for fire safety. Mufflers or exhaust
silencers that meet manufacturer specifications should be considered to reduce exhaust
noise.
ANCHORING & ATTACHMENTS
Generators enclosed in a fixed noise -reduction structure must be anchored to a minimum 3-1/2"
thick concrete slab extending a minimum of 2 feet beyond the generator on all sides, or must be
anchored as required in the manufacturer's installation instructions to prevent vibration.
Page 2 of 4 27
JOINTS. SEALS AND PADDING
Structural joints, cracks, and small, holes Can transmit substantial amounts of noise. Structural
joints should be constructed carefullyAnterleaving of joints helps control sound transmission.
Joints may be caulked with acoustical caulk or sealant. Acoustical tape or other gaskets can
be applied around doors and windows to reduce noise escape.
GENERATOR CLEARANCE
A minimum of 30" of interior structural clearance must be provided on all sides of the generator to
allow access and maintenance, with heat shielding provided as needed.
SOUND TRANSMISSION CLASS
Sound Transmission Class (STC) is used to measure a material's ability to reduce sound. A high
STC rating indicates a good sound insulating material. Essentially, STC is the difference between
sound levels on the side of the wall where the sound originates, and theLside where it is, received.
For example, to reduce a motor sound level of 90 dB to 60 dB, a wall<of'304STC is required.
Below are STC ratings for typical traditional building components.,r
STC Ratings for Typical Building Compon
Building Component Description
Frame Wall
Stucco/Frame Wall
Brick Veneer
Masonry Wall
a. 5/8"x10" Redwood Si\ding
b. `/2" Insulation BoardRShea
c. 2 x 4 studs 16' o.c.��
d. Fiberglass Building Ins°u1el
e. '/2" Gypsum Board attach
a. 7/8" Stucci
VENDORS
These referencesare.provid6d:for informational purposes.and do not represent or imply an
-endorsement of the -'products featured.
GENERATORS,. -
Briggs www6riggsandstratton.com
Cummins Onan. www.cumminsonan.com
Gen eraC www.9enerac:com`
Honda www: hondapowere4uipment.com
-Subaru Robin www.robinamerica:com
Viinco www.winCOQen.com
SOUNDPROOF DRYWALL v
Homasote Sound Barrier. ',www.homasote.com
Quiet.Rock (Soundproof, Drywall) Mww:puietsolut on com
Moto.
i
.51
s
Page 4 of 4
29
ATTACHMENT D
I*
30
l Ordinance No.
2
3 AN ORDINANCE ADDING. SECTION 24 -242, -ENTITLED RESIDENTIAL
4 GENERATOR NOISE, TO ARTICLE IV OF CHAPTER 24 OF THE BUTTE
5 COUNTY CODE
6
7 "The Board of Supervisors of the County of Butte ordains as follows:
8 Section 1., Section 24-242 is added to Article IV; entitled "General Development
9 Regulations" of Chapter 24, entitled "Zoning", of the Butte County Code to read as
10 follows:
11 .24-242. Residential Generator Noise
12 (a) Purpose. -The, purpose of this section is.to provide minimum requirements for the
-13 operation of residential generators, in order to reduce noise levels'and protect the health,
14 property, and well being of Butte County residents and visitors.
15 (b) Definitions. The definition of terms in this section shall be as follows:
16 (1) Agriculture. •The;use of land for commercial agricultural purposes as defined in
17 Section 24-305.
18 (2) Decibel. The logarithmic unit of measurement that quantifies sound levels.
19 (3) Emergency. Disaster or extreme peril to the safety of persons, the environment, and
20 property caused by such conditions as fire, flood, storm, epidemic, riot, earthquake, or
21 hazardous materials.
22 .
23
31
24 () Noise level. The sound pressure level in decibels obtained by using a sound level
25 meter.
26 (6) M Residential generator.,,A machine that produces electricity to support residential
27 uses, including supplying power directly to a residence or for incidental residential
28 activities.
29 (c) Applicability. This section shall apply to the operation of residential•generators. This
30 section does not apply to the area of applicability for Standards for Limited Density
31 Owner -Built Rural Dwellings. Allowable noise levels for Limited Density Owner Built
32 Rural Dwellings are defined under Article VI, Chapter 26 of the Butte County Code.
33 (d) Standards.
34 (I) Noise levels. Residential generators shall notproduce ;* fill"44a A MAWi m••-�''^amore
35 than fifty-five (55) decibels at any point along or outside the property line.
36 (2) Installation. Permanent generators shall be permanently secured on a minimum 3
37 and 1/2 inch thick concrete slab extending a minimum of two feet beyond the generator on
38 all sides, or shall be anchored as required in the manufacturer's installation instructions to
39 prevent vibration.
40 (3) Compliance with Noise Standard. Residential generators not meeting the noise
j
41 standard, , shall aehieve be brought into
42 compliance in any of the following ways:
43 a. Cessation of operation;
44 b. Retrofitting of the generator with a manufacturer -approved muffler or exhaust silencer;
J
45 c. Repair of the generator;
46 d. Replacement of the generator with a conforming generator; or
32
47 ,e. Enclosure of the generator in conformance with subsection (d) (4).of this section.
48 (4) EnclosureAf needed to comply with the maximum decibel level, generators shall be
49 enclosed in a sound reduction enclosure approved by the Building Official. This structure
50 shall be fully `enclosedi and may be constructed consistent with published County
51 guidelines for generator noise reduction, or &MR may be ani commercially
52 manufactured enclosure. Generator enclosures shall reduce noise to. the level required by
53 this section. Enclosures shall be constructed to meet current California Building Code
54 standards, shall provide a minimum of thirty (30) inches of interior structural clearance to
55 allow access on all sides of the generator; and shall be adequately ventilated. and vented.
56 The Director of Development Services shall, publish and maintain guidelines for the
57 construction of effective generator noise reduction enclosures.
58 , (e) Exceptions. The standards of this section are not applicable to -generator noise from
59 the following sources:
60 (1) The use of any generator. related to or connected with an emergency, in order'to
61 protect life or property; or during a temporary power outage; and
62 (2) The operation of any generator.for commercial agricultural use.
63 (f) Noise level measurement. The Count may conduct field testing to verify noise levels;
64 and/or the County may require the operator to conduct field testing. If field testing the
65 o ep rator is required to verify noise levels, a test report showing compliance shall be
66 provided by the operator and submitted to the Director"of Development Services at the
67 operator's expense. For the purpose of evaluating conformance with the standards of this
68 section, noise levels shall be measured as follows:
33
69 (1) Use of meter. Any noise measurement made pursuant to this section shall be;made
70 with a sound level meter calibrated and operated according to the manufacturer's
71 instructions; and
72 (2) Meter location. Exterior noise levels shall be measured at any point along or outside
73 the property line. Where practical, the meter shall be positioned five feet above ,the
74 ground and away from reflective surfaces.
75 (g) Enforcement. Any person who violates any of the provisions of this epee section
76 shall be subject to the provisions of Chapter 41, entitled "Code Enforcement Policies and
77 Procedures", of this code.
78 Section 2. Severability. If any provision of this Ordinance or -the application thereof
79 to any person or circumstances is for any reason held to be invalid by a court of
80 competent jurisdiction, such _provision shall be deemed severable, and the invalidity
81 thereof shall not affect the remaining provisions or other applications of the
82 Ordinance which can be given effect without the invalid provision or application
83 thereof.
84 Section 3. Effective Date and Publication. This Ordinance shall take effect thirty
85 (30) days after the date of its passage. The Clerk of the Board of Supervisors is
86 authorized and directed to publish this ordinance before the expiration of fifteen(15)
87 days after its passage. This Ordinance shall be published once, with the names of the
88 members of the Board of Supervisors voting for and against it, in the
89 a newspaper of general circulation published in the County of
i.
90 Butte, State of California.
34
91 PASSED AND. ADOPTED by the Board of Supervisors of the County of
92 Butte, State of California, on ,the day .of , , 2009, by the
93 following voter
94 AYES:
95 NOES:
96 ABSENT:
97 NOT VOTING`.
35
PLANNING COMMISSION POWERPOINT PRESENTATION
36
BUTTE COUNTY
�OLANNING COMMISSION
Se.ptbmber 24, 2009
Project #: ZCA09-0002 Residential Generator Noise
Request: Amend the zoning ordinance to more effectively implement,
Policies LU -1.1a, LU 6.1a, and N-1 of the General Plan
Owner/ Applicant: Butte County
APN: Various
Planner: Claudia Stuart, Principal Planner
37
Staff recommends adoption of- the --- �
resolution recommending approval of
Zoning Code Amendment ZCA09-0002
Residential Generator Noise to the Board
of Supervisors.
38
•
39
Purpose-
Provide
minimum requirements for operation
of residential generators
-Protect the health, property, and well being of �
Butte County residents and visitors
Aplp icability
Operation of residential generators
Supply -power dirottly-to residence
Supply power,for- incidental residential
activities.
*.Does not apply to area- of applicability for �
Standards for' Limited Density Owner -Built
Dwellings. (Title 25 changes).
41
Noise Standard
• 55 dB at or outside the originating property line
•
•
The,Board of Supervisors confirmed the -recommended
noise standard at their June 23, 2009 meeting
• Operators of non-compliant generators may:
— Cease operation
— Retrofit
— Repair •
— Replace
Tr �4Enclose
42
Enclosure Guide -lines
• Guidelines published and updated by
Department of Development Services
• Enclosures may be commercially manufactured'
or constructed by the operator
• Allow flexibility in
.materials, costs
construction methods,
• Provide general information and, sample
construction methods
• Provide further information sources: Internet
.published 8information,i
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BUTTE COUNTY PLANNING COMMISSION
PUBLIC HEARING
A public hearing before the Butte County Planning Commission will be held on September 24,
2009, at 9:00 a.m. in the Butte County Board of Supervisors' Room, County Administration
Center, 25 County Center Drive, Oroville, California: This hearing will be to accept public
testimony in advance of the Planning Commission's recommendations to the Board of
Supervisors regarding the adoption of two amendments to the Butte County zoning ordinance
entitled "Outdoor Lighting in Residential Areas", and "Residential Generator Noise." Such
adoption would be by the Board at a later, publicly -noticed hearing.
ZCA09-0001 Outdoor Lighting In Residential Areas - This amendment provides standards for the
design and location of outdoor lighting in order to limit light trespass and glare. It requires that
light fixtures be shielded, directed, and located such that direct light is limited to the parcel of
origin. The amendment applies to the following zones: AR (Agricultural Residential), A -SR
(Agricultural Suburban -Residential), FR (Foothill Recreational), M -R (Mountain or Recreation
Subdivisions -Residential), R (Residential), R -N (Residential Nonconforming), RT (Residential -
Mobile Home), SR (Suburban Residential), TM (Timber Mountain) and U (Unclassified). An
amortization period of three months is allowed for existing lighting that requires only re -direction
to be brought into conformance. A six-month amortization period is allowed in all other cases.
ZCA09-0002 Residential Generator Noise - This amendment requires that noise produced by
generators operated to support residential uses shall not exceed 55 decibels at or outside the
originating property line. Residential generators not meeting this standard could be retired,
retrofitted, repaired, replaced, or enclosed in a sound reduction enclosure. Associated guidelines
for the construction of sound -reduction enclosures are provided.
Enforcement of both zoning code amendments would follow procedures in Chapter 41 (Code
Enforcement Policies and Procedures) of the Butte County Code. The proposed zoning code
amendments are exempt from environmental review under the California Environmental Quality
Act pursuant to Section 15308 Action Taken by Regulatory Agencies for Protection of the
Environment. The draft zoning code amendments and Planning Commission staff reports are on
file for public review and comment at the Butte County Planning Division, 7 County Center
Drive, Oroville, California, and are also available for review on the County's website at
http://www.buttecounty.net/dds/Agendas/PC/2009/2009_PC.htm. Comments may be submitted
in writing at any time prior to the hearing or orally at the meeting listed above or as may be
continued to a later date. For information call or send an email to Claudia Stuart, Principal
Planner, (530) 538-7604 or cstuart@buttecounty.net.
BUTTE COUNTY PLANNING COMMISSION
TIM SNELLINGS, DIRECTOR OF DEVELOPMENT SERVICES
Butte. County Department, of Development Services o��TrF0
TIM SNELLINGS, DIRECTOR I PETE CALARCO, ASSISTANT DIRECTOR o 0
0 0
7 County. Center Drive o`o
Oroville, CA 95965
(530) 538-7601 Telephone cOUN'�y
(530) 538-7785 Facsimile
www.buttecounty.net/dds
www.buttegeneralplan.net
ADMINISTRATION. ". BUILDING* PLANNING .
June 23, 2009
Butte.County Board of.Supervisors
25 County Center Drive
Oroviille, CA 95965
SUBJECT: DRAFT ORDINANCE —'RESIDENTIAL GENERATOR NOISE
Recommendation
Staff requests that -the Board of Supervisors
1.: Provide staff with Airection regarding the appropriate allowable noise standard for residential.
generators; and
2. Review the proposed'ordinance and provide additional comments -as desired.
. .
Project Summary.
.Pursuant to the.Board's direction on. Dece.mber:16, 2008 staff has.prepared.a draft ordinance
(Attachment. A) to address noise produced 6y residential generators.
..Background . .
In 'the. fall of 2008,. the. Department .of Development Services received reports. of persistent
generator noise .from residents in the Palermo-Honcut area. The reported noise originates from
residential generators operating .at adistance of several thousand feet from the complainants'
homes. The reports noted that the generator noise disturbed the residents' ability to sleep, reduced
their ability to enjoy the use of.their properties, and potentially. affected local livestock.and wildlife
as well as human Health and, property values. Staff conducted a .site visit on February 4, 2009 and
found the:generator use persisting at that:time. The properties from-whichthe noise originates; and
the affected. properties, are located in the GOL Grazing and Open Lands land use.designation, and
are zoned A-5 (Agricultural, 5 acre'minimum).and:A-40 (Agricultural, 40 acre minimum)..
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
-June 23,2009 -Residential Generator Noise-..
1 of 4 .
The Butte County General Plan Noise . Element identifies 60 decibels (dB) as a maximum
acceptable noise level formeeting indoorpoise requirements. However, it acknowledges that this.
noise_ level may be too high to control effects . on human use of .outdoor areas. The State of
California General Plan Guidelines establish 60 dB as.normally acceptable to residential land uses.
Butte County does not' currently have a noise ordinance. The current Butte County code does
include several noise standards: Section 24-275 '(Recycling facilities) requires that noise generated
by recycling, collection, and processing facilities shall..not exceed 60 decibels as measured at the
property line .of residential property; and shall not otherwise exceed 70 decibels. Standards for the
C -C Community Commercial and -:N-C Neighborhood Commercial zones limit noise generation to
60.decibels at the property line for.6 hours per day, with no noise exceeding 80'decibeIs. However,
none of these standards: address the reported : instance: of 'offensive noise. originating. from. and
affecting parcels.designated and zoned for agriculture, but also serving as residences.
On December 16, 2008 the Board directed staff toidentify options for preparing an interim ' noise
ordinance that would address such' instances of generator.rioise: Staff has sought to.address.the
identified. issues while limiting the breadth'and complexity of the.:ordinance, pending. completion of
a comprehensive noise ordinance pursuant to adoption of Butte County General Plan 2030. In
preparing the interim ordinance,*. staff reviewed ordinances from a number of jurisdictions in
California (e.g., Sacramento County, San . Luis Obispo County);. Florida, .New York and .several
other states.
Discussion
The decibel (dB). scale. is an international standard for .measuring sound pressure,.levels. .Each
three dB increase means that sound energy is doubled, while each .10 dB increase corresponds.to
sound energy increased by. a factor of 10..Sound levels. .further. vary depending on distance from
the noise source. Typical sound -measurements indicate that sound .levels 120 dB .and, above are .
painful or 'injurious (jet. plane. takeoff. at 2.00.feet);. levels above. 85:dB. are 'extremely..loud
(lawnmower); and. Ievels.above 60 dB are loud (for example,.70 dB is the.sound.level of a vacuum
at 10 feet)._. Fifty.. (50) to i 60 -dB .:is. the sound level of -normal 'conversation; 50 OR an average
residence; and 40 dB a quiet room or soft whisper, Human perception of sound pressure levels can
be'more closely simulated by measurement .using the ."A" weighted .scale. Changes of fve.dB(A)
are perceived as quite noticeable,. and a 10 dB(A) change is perceived as twice as loud.
Expectations for residential tranquility in rural . areas. can lead rural jurisdictions to. adopt more
stringent noise standards than.in more urbanized areas.. Allowable noise levels may belower at
night, reflecting stronger expectations for quiet during evening and sleep hours. For example, San
Luis Obispo County limits allowable. sound. levels affecting residential uses to 50 dB during the day
and 45 dB. during the night (Table 1). .
Table 1. Sample County Noise Limits
Jurisdiction
Daytime
Ni httime .
Sacramento Count 1976 .
55 dB A " 7 a.m. —_10 :m. _
50 dB(A) 10 p.m. — 7 a.m.
San Luis Obispo Count 1992
'50 dB 7 a.m. to. 10 .m.
45 dB 10 p.m. — 7 a.m.
Montgomery County, MD .
65 dBA
55 dBA
Jefferson -Count , WV
60 dB A .
50 dB A
dB(A) (or dBA) denotes the use of weighting filters, used to approximate the human ear response. T he measurement
is still in d6.
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
•June.23,'2009 .• Residential Generator Noise-,
2 of 4
The draft interim ordinance establishes a maximum allowable noise: level for residential generators;
and provides construction standards and guidance to assist operators who. need to. enclose their
machines in order to meet that standard..A single �mazimum allowable: noise level is proposed
rather.than separate day/night.standards: The use of a single standard is consistent with :existing
noise limitations in the Butte County; Code,. and will simplify noise measurement and enforcement:
Based on the research and other information outlined above, staff recommends 55 dB as the
maximum allowable noise level for unenclosed residential -generators in the County, including its
rural areas. Sound levels would be measured at a location along or outside the property line -(as
appropriate to account for the effects of topography or built features) while the generator is
operated at full load:
Alternately, should the.Board of Supervisors direct preparation of separate day/night standards,
staff recommends 60 dB for daytime hours and 50 or. 55 dB for nighttime.hours. In this case, staff
also requests confirmation of the appropriate hours for implementation of day/night standards
` '(potentially 7 a.m.. to7 or 10 p.m. for daytime;_and 7 or 10 p.rn. to 7 a.m. for -nighttime).
Operators of generators not meeting .the noise standard could retire or replace the generator,-.
retrofit it,. or enclose it in a.'sound-reducing structure such. that the noise standard is met.
Enclosures could be .purchased from -the generator manufacturer, or constructed by the operator to -
address their generator's specific noise level and other operational cliaracteristics: Safety-
related
standards for, all enclosures are incorporated into•the proposed ordinance. Further guidance for the -
construction of noise -reducing enclosures, including sample specifications, would ,be published and
updated as needed by the Department of Development Services .(Attachment B).
After the effective date of the ordinance, enforcement would follow procedures. in Chapter. 41
(Code Enforcement ..Policies . andi Procedures) of. the Butte . County.. Code...In cases where
complaints are received,, violators would be. notified. of the violation;. the specified action necessary.
to correct the violation, and the: period of time.. allowed for correction. Operators of residential -
generators in violation of allowable noise` levels would have the option of.retiring, replacing, or
enclosing, their generators'. Violations continued .in disregard of .notice .would .be subject to fines
and/or other remedies under the Butte County Code. In order tor effectively enforce the ordinance,'
the County would.need to,make staff available as necessary to investigate complaints:
Relationship to Butte County General Plan -2030
A comprehensive update,of the Butte County General ,Plan and zoning code, -called Butte County
General Plan 2030, is currently underway. 'Establishment of a noise ordinance has been included
as'a final policy alternative for draft Butte County General Plan 2030. Preparation of the noise
ordinance wilf take place after adoption of the 'new General Plan in September 2010: Staff. expects .
that the noise ordinance will provide standards for allowable_ noise levels for a variety'of land uses,.
including noise from residential generators.
BUTTE COUNTY BOARD OF SUPERVISORS AGENDA REPORT
-June 23,2009 -Residential Generator Noise -
3 of 4
. 23 (5) Noise level. The sound pressure level in decibels obtained. by using a sound level
24 meter. .
25 (6) Residential•generator: A machine that-produces electricity to support residential uses,'
26 'including supplying-power directly to a residence or.for incidental.residential'activities..
27 (c) Applicability. _This sectiorfshal.1 apply to.the operation of residential generators.. This
28 . section does not apply :to the area of applicability for Standards foimited Density
29.- ..Owner-Built Rufal Dwellings..Allowable noise levels for Lirm ed*Density Owner-Built
30 .Rural Dwellings are'defined.under Artericle VI, Chapt- 6 of the Butte-County Code..
31 (d). Standards:.,
32 (!)Noise, levels. Residential generators shall produce`at#full load a maximum of fifty-five
33. .(55) decibels at any point along or outside the property line
34 (2)' Installation: Perm anent'generators:shall be permanently secured ona minimum 3
35 . 'andl.l2 inch•thick concrete` s ab' extending a inimmum of two feet.beyond the generator on
.36 all sides,. or shall Wanchored "as "required in the manufacturer.'s installation instructions to
37 , prevent vibration IOOV
k.�
77
38... (3) Compliance with Noise Standard:rResidential generators not meeting the noise'
39 standard, and which are:the subject of a complaint, shall.achieve compliance. in any of the
r'
40 'following ways ... ..
41 a. Cessation of.operaton; .
42 b. Retrofitting of the.generator with amanufacturer-approved muffler or exhaust silencer;
43 . c. Repair of the generator; '
.44 d. Replacement of the gerieratorwith a.conforming generator; or ...'
45 e. Enclosure .of the. generator.in conformance with subsection (d) (4) of this section... .
46 (4) Enclosure. If needed.to.comply with the maximum decibel level, generators shall -
be. -47 enclosed in a sound reduction enclosure.approved by.the Building Official. This structure
48 : ' shall be fully enclosed and constructed'consistent-with. published County guidelines -for.
49 'generator. noise reduction, or: shall be: an approved. commercially manufactured enclosure:..
50,; Generator enclosures "shall reduce noise to the: level required. by this section. Enclosures
'51, shall: be constructed to:meetcurrent California Building Code standards, shall provide a
52 minimum of thirty. (36) inches of interior structural clearance toallowaccess.on all -sides.-"
t
53 of the generator; and�shalI be adequately ventilated and vented. The Director of
54 Development Services shall publish and maintain guidelines for the construction'of
•
55 effective generator.noise reduction enclosures.
56 (e) Exceptions. The standards ofihis.se tion-are.riot applicable to generator noise from
57 the following: sources:
58 (1) The use of any gennerato lated.to 'or. co emergency, in order -to:.:
59. protect life or property, or during a temporary power outage. .
60 (2) The operation 6f any generator for comm rcial agricultural use
61. (f) Noise level measurement. If Mdjestmg is, required, to verify noise levels, a test report
62 showing compliance shall`be provided by the operator and submitted to the Director of
63 ;Development Services at- the operator's expense: For the purpose of evaluating
64 conformance with'standards of this section, noise levels shall be measured as follows:
65. (1) Use of meter. Any noise measurement made pursuant'to this section shall be made
66 with a sound level meter calibrated and operated'according to the manufacturer's
.67 instructions; .arid. .
. 68 . (2) Meter location. Exterior noise. levels shall.be-measured at any point along or. outside.-.. .
69 the property line. Where practical, the meter shall be "positioned.five feet above the.
70 ground and away from reflective surfaces. '
71 �(g) Enforcement. Any person who violates any. of the provisions of this ordinance shall
.72 be. subject to:the,.provisions of Chapter 41 -Code Enforcement Policies and Procedures.
73' Section 2. - Severability. If any provision'of.this'Ordinance or .th'e application thereof .
74 to any person. or' circumstances is "for an "reason held t6/be"Y
valid by a."court of .
_ Y
75 competent jurisdiction, such provision shall be deemekseverable, andq e invalidity
76 thereof shall not affect the ' remaining provisions or other applications* -of the
77 'Ordinance .which can be given- effect without the 'Inv al"id provision or, application
78 thereof..
79 Section 3. Effective Date and Publication. :This,Ordinance shall take effect thirty
80 (30) days after the "date o"'�f i'ts�passage. "The Clerk of the. Board. of Supervisors is
81authorized, and directed�to publish this ordir ce-before the expiration of fifteen,(1,5)
NXI" A
Y-
82 days' after itsypassage.. This Ordinance "shall' be .published once; with.the _names of the
83 rriembers of the "Board of Supervisors- voting for and "against,' *it,',.,in "the .
a° ..
84 ` a news` a er. of eneral circulation : ublished iii the Cour of
p P g P County
85' Butte; State.of California.
;,.
"x _x
86 :. PASSED AND ADOPTED by the Board . of Supervisors .of the County of
87 .Butte, State .of California, on •the day of 2009; by the
.88 following vote:'
80" AYES:' .
90 ` NOES:..
s
Butte. County Department of Development Services. , : o- VTtF0.
-TIM SNELLINGS;.DIRECTOR l PETE CALARCO, ASSISTANT DIRECTOR o o.
-�._ f
• 7 County Center Drive ... . • � o o- er---:�
Oroville, CA .95965 O --- - - o .
(530) 538-7601 Telephone CDU 14
(530) 538-7785 Facsimile
www.buttecountv.neVdds .
www.buttegeneralplan.net
ADMINISTRATION * BUILDING " PLANNING
RESIDENTIAL GENERATORS
NOISE REDUCTION ENCLOSURE GUIDELINES
June 2009...
Butte County requires that residential generators p�oducing sound levels of over 55 decibels. (dB) .
at the property line be enclosed in. a noise reduction enclosure which reduces the,s and to below
55.dB..Enclosuresare not generally required forgeneratorsd producing lower noise�e els: ;
The following information' is intended to provide guidance to'generator owners and operators with
respect to achieving effective noise control -.--.This information is,provided only as guidance, and
should not be construed as an endorsementof'any product by Butte?County: Generator operators.
are free to choose other construction methods 'products, or vendors th meet the requirements
of the Butte County Code and other applicable codesk:
The design of any structufrequired to reduce generator nolsemust be approved by the Building.
Official.Generator enclosures must`be built and properly vented for air intake;and exhaust, and
-constructed.to meet currently adopted.California building codes. Key noise reduction techniques
are listed below. Wh ever design pfeatures are. selected; noise levels must. be reduced to 55AB
at the nearest property line- bey nd
NOISE REDUCTION -TECHNIQUES.
• orThickmat&61s
• , Dennse.materials =
• Re's t materials
• Dissimilar layers {
• Inueased,air space in wall partitions
• Acoustical structural materials, lining, and.sealants
• Sound-absorbing,insulation.
• Sealed joints ariddges
• Reduced vibration
Silenced exhaust
WALL MATERIALS
In general (for traditional wall materials)'the denser and/or.thicker the wall, the more it will reduce .
noise. If layers are made of different materials and/or thicknesses; sound transmission is further
eeduced..Newer, readily available sound -'reducing panel. materials are designed to.reduce
noise without substantially increasing wall thickness. These include manufactured'soundboard
or sound barrier wall. applications (Homasote Sound Barrier; Quiet Rock), medium -density
fiberboard, and fiber cement siding (Hardi board). Alternately,.a'double_ layer of gypsum
may be. used for interior walls to help dampen sound.
. Page 1' of 4
STUDS AND WALL SYSTEMS
The interior and exterior of the structure may be separated Using staggered studs or a
• double wood stud partition. Or, metal studs may be used. Sound barrier wall panels can be
attached directly to the studs and covered with gypsum board which is fixed to the. sound barrier
-but not to the studs. This will help.reduce sound.transmission'through the structure. Padding r '
tape can further help reduce sound transmission through the studs.
Factors wtii .6 influence sound attanuailon of
-wants',.. . .
• LOwer eourid attenuali0o - Higher soundattenuatan
Increases mass'
Usp of ale space':
- - -- InueaaeG wlotn of afrapace• - - .
• � / i •_ .. Wldeapacing0etweenattid5. '
11I l SlagyeredstWs
• _ ,l .
Use 0t:reslltentattachmenta •,
- cm.m•s/w wm /'05. .4`i• �¢''rcommowni
STC u 35
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LINING AND INSULATION
Sound -reducing linings a4insulation include mineral wool; mass -loaded vinyl; and acoustical .
panels, mats�o�soundproofng composites. Acoustical blankets are made from sound--'
absorbing materials and can reduce noise.'Acoustical blankets can be placed in the wall space or - -
can be.effective ih"lightweight portable construction.
EXHAUST SYSTEM
1
Much of a. generator's `poise comes out of its exhaust system. However, mufflers must be
compatible with the generator system and properly vented for fire Safety: Mufflers or exhaust
silencers that meet manufacturer specifications should be considered to reduce exhaust
noise.
ANCHORING & ATTACHMENTS
Generators enclosed in a fixed,noise-reduction structure must be anchored to a minimum 3-172"
thick concrete slab extending, a minimurri of 2 feet beyond the generator on all sides, or must be
anchored as required.in the manufacturer's installation instructions to prevent vibration. `
Page 2 of 4
JOINTS, SEALS AND PADDING
Structural joints;. cracks, and small holes carr transmit substantial amounts of noise. Structural
joints should be constructed carefully. Interleaving of joints helps control sound transmission.
Joints may be caulked with. acoustical caulk or sealant. Acoustical tape-or other,gaskets can
be applied around doors-and windows to reduce noise escape:
-GENERATOR CLEARANCE `
A minimum of 30 of interior structural clearance must be provided on all sides of the generator to
allow access and maintenarice, with heat shielding provided as needed.
SOUND TRANSMISSION CLASS
Sound Transmission Class (STC) is used to measure a material's ability to' reduce sound. A high' .
STC rating indicates a good sound. insulating material. Essentially,:STC is the difference between •
sound levels-on the side of�the wall.where the sound .originates, and the'side where it is received..
For example;.to. reduce a motor sound level of 90 dB to 60 dB, •a walhof%30STC is required.
Below are STC ratings for typical traditional building components
STC Ratings for*Typical Building Components
Building Component Description STC Rating (est.)
Frame Wall a. 5/8"x10" Redwood Siding 39 d6
•b. Yi' Insulation Board'Sheathiag
C. 2 x 4 studs 16" o.c. i
Fiberglass Building Insulation
e. '/i' Gypsum Board attached'directly to studs
Stucco/Frame Wall a: 7/8" St c : 46 d6
b. No: 15 felt�Buildmg'Paper�and
1" Wire Mesh
6`
c. 2 x 4 studs 1� O
'd: F, iberglass Building Insulation
e,KYV Gypsum.Board attached directly.
#o! studs
Brick Veneer Wall a. Fac B k .: 56 dB'. .
b'/z" airspace-with metal ties
+insulation board sheathing
d. 2�x 4�studs 16" o.d.
e: Fiberglass Building Insulation
f. '%z'ypsum board attached
_
directly, to studs. .
Masonry.Wall . t..:, a: 1" Stucco 49AB
b. 8" thick.Hollow Concrete Block
c.''/2' gypsum board attached to furring strips.
Source: US Dept. of Housing and.Urban Development; National Institute of Standards
OTHER INFORMATION SOURCES
Noise-reducing design features-can.be combined as needed to reduce generator noise while also.
meeting building codes. Information about sound-reducing structural components and
combinations can be found the Fire Resistance Design Manual, which.also addresses sound .
control. The manual is published,.by the Gypsum Association.
Online sources include STCratings.com (www.stcratin sq com). This website.provides STC ratings
for additional types of wall assemblies. The Department of Development Services can assist you
in locating the.information needed to. meet the County's residential generator noise standards. .
Page.3 of 4
Butte :County Depart►nent� of Devel, ent' Services
TIM SNELLINGS, DIRECTOR I PETE CALA,RCO, ASSISTANT DIRECTOR, .
7 County Center Drive.
Oroville, CA 95965
(530) 538-7601 Telephone.
(530.) 538-7,786, Facsimile
www: buttecounty:netfdd's.
www.buttepen,eral'blary:r et,
ADMI_NISTRATION.' BUILDING-* PLANNIN,G
June 1'9; 2009
.Costel Anghe,luta
•:3387 Myers 5treef
Oroville; CA 95.966
Re Board of Supervisors;Agerl- forJtj 2-3-,, 200-9, Residential Generator Noise Ordinance
Dear Mr. Angheluta;
It'has come to my attention that you may ;be' interested; in an it that is to ,be, considered by. the
Butte Countv Board of ,Supervisors 'next .week: The item is an initial draft df,a proposed ordinance
Ad regulate:residential generator noise This: discussion -will be Item 4.07 on the Board's June;23,
2Q0'9 regular agenda :Enclosed are the draft ordinance' and agenda report;addressing this item.
The Board's discussion will provide ,staff with direction regard':ng an appropriate standard for
allowable:leveis:'of residential. generator noise, and also provide any. other:directibh to staff;
regarding whether, or•how the Board bf Supervisors --would like the proposed regulations,modified
prion to Planning Commission; review ,and final adoption :ty the Board..
Should you with tocomment; to the Board, of Supervisors regarding this item, written or emailed
comments:are accepted through the,Cleek, ofthe. Board(kmoghannamCa2b'uftecounty:net), or,
through me (66tuarf(&,butteco6nfy.,66t). Alteenately, _you may wantto attend the -meeting in order'to
provide comments In person and;,answer any, gppstlonS that the. Supervisors; may have.
The June. 23rd °meeting starts. at -0:0 . 0 am This will not be a timed item, so, the discussion ,could, take
place at.any time duriogahe Board of,Supervisors"meeting The corp plete meeting agenda, agenda
report and draft ordinance are :also posted on the. County's, website at
Afterataff receives the Board`s. direction the, ordinance will be;moved forward to a :Planning
Commission hearing fora recommendation; It w 11 -then return to the, atd of Supervisors; for final
:adoption. The Board's directi''mriw t week will clarify>what.the Supervisors wish to,address through
that process. The future Planning .Commission and Board, of Supervisors hearings will,provide
additional opportunities', to comment on,the proposed 'zoning code amendment.