Ordinance No. 952 - Adopting By Reference Chapter 12.84 Entitled "Low Impact Development Standards" of the Los Angeles County Code and Incorporating Said Chapter Into Chapter 13.16 of the Rosemead Municipal Code with AmendmentsORDINANCE NO. 952
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF ROSEMEAD
ADOPTING BY REFERENCE CHAPTER 12.84 ENTITLED "LOW IMPACT
DEVELOPMENT STANDARDS" OF THE LOS ANGELES COUNTY CODE
AND INCORPORATING SAID CHAPTER INTO CHAPTER 13.16 OF THE
ROSEMEAD MUNICIPAL CODE, WITH AMENDMENTS
WHEREAS, the City of Rosemead ( "City ") is a permittee under the California
Regional Water Quality Control Board, Los Angeles Region Order No. R4- 2012 -0175,
issued on November 8, 2012, which establishes Waste Discharge Requirements for
Municipal Separate Storm Sewer Systems (MS4) discharges within the coastal
watersheds of Los Angeles County, except those discharges originating from the City of
Long Beach MS4; and
WHEREAS, Order No. R4- 2012 -0175 contains requirements for municipalities to
establish a Low Impact Development Ordinance and the City now desires to adopt a
Low Impact Development Ordinance as required by Order No. R4- 2012 -0175; and
WHEREAS, the Los Angeles County Board of Supervisors has already adopted
into the Los Angeles County Code Chapter 12.84 entitled "Low Impact Development
Standards" which contains the same requirements that the City will need to comply with
and enforce; and
WHEREAS, California Government Code Section 50022.9 authorizes the City to
adopt by reference County ordinances and codes; and
WHEREAS, the City of Rosemead desires to adopt by reference Chapter 12.84
entitled "Low Impact Development Standards ", of the Los Angeles County Code.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF ROSEMEAD DOES
ORDAIN AS FOLLOWS:
SECTION 1. Chapter 13.16 of the Rosemead Municipal Code is hereby
amended to include Chapter 13.16.180 — Low Impact Development to read as follows:
13.16.180 — Low Impact Development.
A. Title — This Section, 13.16.180, shall be known as the Low Impact Development
Ordinance of the City of Rosemead
B. Adoptions by Reference —
1. Except as amended in Section 13.16.180.C, below, Chapter 12.84 of the Los
Angeles County Code, which is entitled "Low Impact Development Standards," is
hereby incorporated in its entirety by reference and expressly incorporated herein.
Chapter 12.84 of the Los Angeles County Code is hereby made a part of this Chapter
13.16.180 as if, for all intents and purposes, fully set forth in this Chapter. This adoption
by reference shall include any subsequent amendments to Chapter 12.84 unless
modified in this Chapter, 13.16.180.
2. A certified copy of Chapter 12.84 of the Los Angeles County Code is on file in
the office of the City Clerk for public record and inspection.
3. If there is any inconsistency between any provisions of Chapter 12.84 of the
Los Angeles County Code and other provisions of this Municipal Code, such other
provisions of this Municipal Code shall prevail.
C. Amendments — Chapter 12.84 of the Los Angeles County Code is hereby amended
as follows:
1. Section 12.84.420 of Chapter 12.84 of the Los Angeles County Code is hereby
amended to amend the following definition:
"County" means the City of Rosemead
2. Section 12.84.420 of Chapter 12.84 of the Los Angeles County Code is hereby
amended to amend the following definition:
"Director" means the Director of Public Works of the City of Rosemead
3. Section 12.84.420 of Chapter 12.84 of the Los Angeles County Code is hereby
amended to amend the following definition:
"Public Works" means the City of Rosemead Department of Public Works
4. Section 12.84.430.E.2 of Chapter 12.84 of the Los Angeles County Code is
hereby amended to amend to read as follows:
"2. Any development project for which a complete discretionary or
nondiscretionary permit application was filed with the City of Rosemead prior to
December 28, 2012."
5. Section 12.84.440.B of Chapter 12.84 of the Los Angeles County Code is
hereby amended to read as follows:
"B. Low impact development plans shall be submitted in accordance with
the Low Impact Development Standards Manual issued by the County of Los Angeles
Department of Public Works, a copy of which shall be located in the Public Works
Department."
D. Responsibility for Administration — This chapter shall be administered by the Director
of Public Works of the City of Rosemead.
SECTION 2. This ordinance shall take effect thirty (30) days after its adoption in
accordance with California Government Code Section 36937.
SECTION 3. The City Clerk shall certify to the passage and adoption of this
Ordinance and shall cause the same to be published and /or posted in accordance with
applicable law.
PASSED, APPROVED AND ADOPTED THIS 12 DAY OF MAY, 2015.
Margar Clark
Mayor
ATTEST:
oria Molleda
City Clerk
APPROVED AS TO FORM:
City Attorney
STATE OF CALIFORNIA )
COUNTY OF LOS ANGELES ) SS.
CITY OF ROSEMEAD 1
I, Gloria Molleda, City Clerk of the City of Rosemead, California, do hereby certify that the
foregoing Ordinance No. 952 was regularly introduced and placed upon its first reading at a
regularly meeting of the City Council on the 28TH of April, 2014. There after said Ordinance was
duly adopted and passed at a regular meeting of the City Council on the 12th of May, 2015 by the
following vote to wit:
AN ORDINANCE OF THE CITY COUNCIL OF
THE CITY OF ROSEMEAD ADOPTING BY
REFERENCE CHAPTER 12.84 ENTITLED
"LOW IMPACT DEVELOPMENT STANDARDS"
OF THE LOS ANGELES COUNTY CODE AND
INCORPORATING SAID CHAPTER INTO
CHAPTER 13.16 OF THE ROSEMEAD
MUNICIPAL CODE, WITH AMENDMENTS
Yes:
Alarcon, Armenta, Clark, Low, Ly
No:
None
Abstain:
None
Absent:
None'
s o L A�X k2l-
Gloria Molleda
City Clerk
Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
Sections:
12.84.410 Purpose.
12.84.420 Definitions.
12.84.430 Applicability.
12 84 440 Low Impact Develooment Standards.
12 84 445 Hvdromodification Control,
12.84.450 LID Plan Review.
12 84 460 Additional Requirements.
12.84.410 Purpose.
The purposes of this chapter are as follows:
A. Lessen the adverse impacts of stormwater runoff from development and urban runoff on natural
drainage systems, receiving waters and other water bodies.
B. Minimize pollutant loadings from impervious surfaces by requiring development projects to
incorporate properly designed, technically appropriate BMPs and other LID strategies.
C. Minimize erosion and other hydrologic impacts on natural drainage systems by requiring
development projects to incorporate properly designed, technically appropriate hydromodification
control development principles and technologies.
D. The provisions in this Chapter 12.84 shall be construed to augment any county, state, or federal
ordinance, statute, regulation, or other requirement governing the same or related matter, and where
a conflict exists between a provision in this Chapter 12.84 and such other ordinance, statute,
regulation, or requirement, the stricter provision shall apply to the extent permitted by law.
(Ord. 2013 -0044 § 1, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
12.84.420 Definitions.
The following definitions shall apply to this chapter:
A. 'Basin Plan" means the Water Quality Control Plan, Los Angeles Region, Basin Plan for Coastal
Watersheds of Los Angeles and Ventura Counties, adopted by the Regional Water Board on June
13, 1994 and subsequent amendments.
B. 'Beneficial Use" means the existing or potential use of receiving waters as designated by the Los
Angeles or Lahontan Regional Water Quality Control Boards in their respective basin plans for the
County.
C. 'Best Management Practices ('BMPs ")" are practices or physical devices or systems designed to
prevent or reduce pollutant loading from stormwater or non - stormwater discharges to receiving
Las Angeles County, California, Code of Ordinances Page 1
Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
waters, or designed to reduce the volume of stormwater or non - stormwater discharged to the
receiving water.
D. "Capital Flood" means the runoff produced by a fifty (50) -year frequency design storm falling on a
saturated watershed (soil moisture at field capacity). A fifty (50) -year frequency design storm has a
probability of 1/50 of being equaled or exceeded in any year.
E. "County" means the County of Los Angeles.
F. "Designated Project' means any development project described in subsection A of Section
12.84.430
G. "Development" means activity requiring discretionary or non - discretionary land use or construction
approval from the County that results in the creation, addition, modification, or replacement of
impervious surface area, which replacement is not part of routine maintenance activity. Development
includes, but is not limited to, land subdivisions; the construction, installation, addition, or
replacement of a building or structure; expansion of a building footprint; and land- disturbing activities
related to structural or impervious surfaces. Development shall not include routine maintenance of
original lines and grades and /or hydraulic capacity.
H. "Director" means the Director of Public Works.
I. "Excess Volume" means the additional volume of stormwater caused by development; excess
volume is determined by calculating the difference in the volume of runoff under undeveloped and
post - developed conditions, using the water quality design storm event.
J. " Hardscape" means any durable, pervious or impervious surface material, including paving for
pedestrians and vehicles.
K. "Hydromodification" means the alteration of a natural drainage system through a change in the
system's flow characteristics.
L. "Low Impact Development ( "LID ")" means technologies and practices that are part of a sustainable
stormwater management strategy that controls stormwater and urban runoff on site.
M. "Natural Drainage System" means any unlined or unimproved (not engineered) creek, stream, river,
or similar waterway.
N. "Non- designated Project" means any development project that is not included in subsection A of
Section 12.84.430
O. "Pollutants of Concern" means chemical, physical, or biological components of stormwater that
impair the beneficial uses of receiving waters, including those defined in the Federal Clean Water Act
section 502(6) (33 United States Code section 1362(6)), and incorporated by reference into
California Water Code section 13373.
P. "Public Works" means the Los Angeles County Department of Public Works.
Q. "Receiving Water" means a "water of the United States" (as defined in 33 C.F.R. section 328.3(a)(7))
into which waste and /or pollutants are or may be discharged.
R. "Regional Water Board" means the California Regional Water Quality Control Board, Los Angeles
Region.
S. "Softscape" means the horticultural elements of a landscape, such as soil and plants.
T. "Standard Industrial Classification (SIC)" means a classification pursuant to the current edition of the
Standard Industrial Classification Manual issued by the Executive Office of the President of the
United States, Office of Management and Budget, and as the same may be periodically revised.
U. "Stormwater" means runoff that occurs as the result of rainfall.
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Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
V. " Stommwater Quality Design Volume ("SQDv ")" means the runoff generated by a water quality design
storm event.
W. "Urban Runoff' means surface flows, other than stormwater, emanating from development.
X. "Water Quality Design Storm Event" means any of the volumetric or flow rate based design storm
events for water quality BMPs identified in the National Pollutant Discharge Elimination System
Municipal Stormwater Permit for the County of Los Angeles.
(Ord. 2013 -0044 § 2, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
12.84.430 Applicability.
A. Designated Projects. The following development projects shall comply with the provisions of
subsection C of Section 12.84.440, below:
1. All new development projects involving one (1) acre or greater of disturbed area and adding
more than ten thousand (10,000) square feet of impervious surface area;
2. New industrial parks with ten thousand (10,000) square feet or more of surface area;
3. New commercial malls with ten thousand (10,000) square feet or more of surface area;
4. New retail gasoline outlets with five thousand (5,000) square feet or more of surface area;
5. New restaurants (SIC 5812) with five thousand (5,000) square feet or more of surface area;
6. New parking lots with five thousand (5,000) square feet or more of impervious surface area, or
with twenty -five (25) or more parking spaces;
7. New automotive service facilities (SIC 5013, 5014, 5511, 5541, 7532 -7534 and 7536 -7539) with
five thousand (5,000) square feet or more of surface area;
8. New development located in or directly adjacent to or discharging directly to a Significant
Ecological Area ( "SEA "), as defined in Section 22.08.190 of Title 22 of this Code, which will
discharge stormwater runoff that is likely to impact a sensitive biological species or habitat and
create two thousand five hundred (2,500) square feet or more of impervious surface area; and
9. Redevelopment Projects. Development that results in the creation or addition or replacement of
either (i) five thousand (5,000) square feet or more of impervious surface area on a site that
has been previously developed as described in subsections 1 -8, above; or (ii) ten thousand
(10,000) square feet or more of impervious surface area on a site that has been previously
developed with a single family home.
a. Where more than fifty percent (50 %) of impervious surfaces of a previously developed site
is proposed to be altered, and the previous development project was not subject to post -
construction stormwater quality control requirements, the entire development site (i.e., both
the existing development and the proposed alteration) shall comply with the provisions of
subsection C of Section 12.84.440, below.
b. Where less than fifty percent (50 %) of impervious surfaces of a previously developed site
is proposed to be altered, and the previous development project was not subject to post-
construction stormwater quality control requirements, only the proposed alteration shall
comply with the provisions of subsection C of Section 12.84.440, and not the entire
development site.
c. Redevelopment does not include routine maintenance activities that are conducted to
maintain original line and grade, hydraulic capacity, original purpose of facility or
emergency redevelopment activity required to protect public health and safety. Impervious
surface replacement, such as the reconstruction of parking lots and roadways which does
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Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
not disturb additional area and maintains the original grade and alignment, is considered a
routine maintenance activity. Redevelopment does not include the repaving of existing
roads to maintain original line and grade.
B. Non - designated Projects. Any development project that is not included in subsection A, shall comply
with the provisions of subsection D of Section 12.84.440, as follows:
1. Where the development project involves a previously undeveloped site or results in an addition
or alteration of at least fifty percent (50 %) of the impervious surfaces of an existing developed
site, the entire site shall be brought into compliance with the provisions of subsection D of
Section 12.84.440
2. Where the development project results in an addition or alteration of less than fifty percent
(50 %) of the impervious surfaces of an existing developed site, only such incremental
development shall comply with the provisions of subsection D of Section 12.84.440
C. Street and Road Construction. In addition to complying with all other applicable provisions of Section
12.84.440, development projects involving street and road construction of ten thousand (10,000)
square feet or more of impervious surface area shall follow USEPA guidance regarding "Managing
Wet Weather with Green Infrastructure: Green Streets 26" (December 2008 EPA - 833 -F -08 -009) to
the maximum extent practicable. This subsection applies to standalone streets, roads, highways, and
freeway projects, and also applies to streets within larger projects.
D. Single Family Hillside Homes. In addition to complying with all other applicable provisions of Section
12.84.440, development projects involving the construction of a single- family home in a hillside
management area (as defined in Section 22.08.080 of Title 22 of this Code) shall Implement the
following measures:
1. Conserve natural areas;
2. Protect slopes and channels;
3. Provide storm drain system stenciling and signage;
4. Divert roof runoff to vegetated areas before discharge, unless the diversion would result in slope
instability; and
5. Direct surface flow to vegetated areas before discharge unless the diversion would result in
slope instability.
E. Exemptions. This chapter shall not apply to any of the following development projects:
1. Any Non - designated Project that results in an addition or alteration of less than fifty percent
(50 %) of the impervious surfaces of an existing developed site consisting of four (4) or fewer
residential units; and
2. Any development project for which a complete discretionary or non- discretionary permit
application was filed with the Los Angeles County Department of Regional Planning, Public
Works, or any County- controlled design control board, prior to January 1, 2009.
(Ord. 2013 -0044 § 3, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
12.84.440 Low Impact Development Standards.
A. The LID standards of this chapter:
1. Mimic undeveloped stormwater runoff rates and volumes in any storm event up to and including
the Capital Flood;
2. Prevent pollutants of concern from leaving the development site in stormwater as the result of
storms, up to and including a Water Quality Design Storm Event; and
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Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
3. Minimize hydromodification impacts to natural drainage systems.
B. The Director shall prepare, maintain, and update, as deemed necessary and appropriate, a manual
( "LID Standards Manual'), which shall include urban and stormwater runoff quantity and quality
control development principles and technologies for achieving compliance with the provisions of this
section. The LID Standards Manual shall also include technical feasibility and implementation
parameters, as well as other rules, requirements, and procedures as the Director deems necessary,
for implementing the provisions of this Chapter 12.84
C. Designated Projects. To meet the standards described in subsection A of this section, development
projects described in subsection A of Section 12.84.430 shall comply with the following
requirements:
1. The project shall retain one hundred percent (100 %) of the Stormwater Quality Design Volume
( "SWQDv ") on -site, through infiltration, evapotranspiration, rainfall harvest and use, or a
combination thereof, unless the Director determines that it would be technically infeasible to do
so;
2. If the Director determines that it would be technically infeasible to retain one hundred percent
(100 %) of the SWQDv on -site, the project shall comply with one of the following alternative
compliance measures:
a. The project shall provide for on -site biofiltration of one and one -half (1.5) times the portion
of the SWQDv that is not retained on -site;
b. The project shall include infiltration or bioretention BMPs to intercept the portion of the
SWQDv that is not retained on -site at an offsite location, as approved by the Director. The
project shall also provide for treatment of the portion of the SWQDv discharged from the
project site, as approved by the Director;
c. The project shall provide for the replenishment of groundwater supplies that have a
designated beneficial use in the Basin Plan;
(1) Groundwater replenishment projects shall include infiltration, or bloretention BMPs to
intercept the portion of the SWQDv that is not retained on -site at an offsite location, as
approved by the Director;
(ii) Groundwater replenishment projects shall also provide for treatment of the portion of
the SWQDv discharged from the project site, as approved by the Director;
d. The project shall include infiltration, bioretention, or rainfall harvest and use BMPs to
retrofit an existing development, with similar land uses as the project, to intercept the
portion of the SWQDv that is not retained on -site; or
e. The County, independently or in conjunction with one (1) or more cities, may apply to the
Regional Water Board for approval of a regional or sub - regional stormwater mitigation
program to substitute in part or wholly for the provisions of this chapter for the area
covered by the regional or sub - regional stormwater mitigation program. If the Regional
Water Board approves the program, the provisions of the program shall apply in lieu of any
conflicting provisions of this chapter.
D. Non - designated Projects. To meet the standards described in subsection A of this section, any
development project described in subsection B of Section 12.84.430, above, shall comply with the
following requirements:
1. A development project consisting of four (4) or fewer residential units shall implement at least
two (2) LID BMP alternatives listed in the LID Standards Manual, which alternatives include, but
are not limited to, disconnecting impervious surfaces, using porous pavement, downspout
routing, a dry well, landscaping and Irrigation requirements, and a green roof;
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Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
2. A development project consisting of five (5) or more residential units, or a nonresidential
development project, shall comply with the following requirements:
a. The excess volume from each lot upon which such development is occurring shall be
infiltrated at the lot level, or in the alternative, the excess volume from the entire
development site, including streets and public right -of -way, shall be infiltrated in sub -
regional facilities. The tributary area of a sub - regional facility shall be limited to five (5)
acres, but may be exceeded with approval of the Director. When the Director determines
that infiltration of all excess volume is not technically feasible, on -site storage, reuse, or
other water conservation uses of the excess volume is required and shall be Implemented
as authorized by the Director in accordance with the requirements and provisions specified
in the LID Standards Manual; and
b. The runoff from the water quality design storm event associated with the developed site
hydrology must be treated to the satisfaction of the Director before discharge.
(Ord. 2013 -0044 § 4, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
12.84.445 Hydromodification Control.
A. Exemptions. The Director may grant exemptions from the provisions of this Section 12,84.445 for the
following types of development projects where the Director determines that downstream channel
conditions and proposed discharge hydrology indicate that adverse hydromodification effects to
beneficial uses of natural drainage systems are unlikely:
1. The replacement, maintenance or repair of existing, publicly- maintained flood control facilities,
storm drains, or transportation networks;
2. Redevelopment of a previously developed site in an urbanized area that does not increase the
effective impervious area or decrease the infiltration capacity of pervious areas compared to the
pre - project conditions;
1 Projects that have any increased discharge directly or through a storm drain to a sump, lake,
area under tidal influence, into a waterway that has an estimated hundred (100) -year peak flow
of twenty -five thousand (25,000) cubic feet per second ( "c.f.s. ") or more, or other receiving
water that is not susceptible to hydromodification impacts;
4. Projects that discharge directly or through a storm drain into concrete or other engineered
channels (e.g., channelized or armored with rip rap, shotcrete, etc.), which, in turn, discharge
into receiving water that is not susceptible to hydromodification impacts;
S. Non - designated Projects disturbing an area less than one (1) acre or creating less than ten
thousand (10,000) square feet of new impervious area; or
6. Single family homes that incorporate LID BMPs in accordance with the LID Standards Manual.
B. The LID Standards Manual shall include hydromodification control development principles and
technologies for achieving compliance with the provisions of this Section 12.84.445 as well as other
rules, requirements and procedures as the Director deems necessary, for implementing the
provisions of this section.
C. Unless excluded by subsection A, above, or excused pursuant to subsection D, below, development
projects must fully mitigate off -site drainage impacts caused by hydromodification and changes in
water quality, flow velocity, flow volume, and depth /width of flow, as determined by the Director, in
accordance with the requirements and provisions specified in the LID Standards Manual.
1. Sediment transport analysis shall be required when the project is tributary to any natural
drainage system with a Capital Flood flow rate greater than five thousand (5,000) c.f.s.
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Title 12 - ENVIRONMENTAL PROTECTION
Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
D. If the Director determines that it would be infeasible for a development project to comply with the
provisions of subsection C of this section, and the project disturbs an area less than fifty (50) acres,
written consent to the unmitigated impacts shall be obtained from the owner of every impacted
downstream property. In addition, the development project shall comply with one of the following
alternative requirements:
1. The project shall retain on -site, one hundred percent (100 %) of the stormwater volume from the
runoff of the ninety -fifth (95th) percentile, twenty -four (24) -hour rainfall event, through infiltration,
evapotranspiration, and /or harvest and use;
2. The runoff flow rate, volume, velocity, and duration for the project's post- development condition
shall not exceed the pre - development condition for the two (2) -year, twenty -four (24) -hour
rainfall event; or
3. The Erosion Potential ( "Ep ") in the receiving water channel shall approximate one (1), as
demonstrated by a hydromodification analysis study approved by the Director.
E. If the Director determines that it would be infeasible for a development project to comply with the
provisions of subsection C of this section, and the project disturbs an area fifty (50) acres or more,
written consent to the unmitigated impacts shall be obtained from the owner of every impacted
downstream property. In addition, the development project shall comply with one of the following
alternative requirements:
1. The project shall infiltrate on -site at least the runoff from a two (2) -year, twenty -four (24) -hour
rainfall event;
2. The runoff flow rate, volume, velocity, and duration for the project's post - development condition
shall not exceed the pre - development condition for the two (2) -year, twenty -four (24) -hour
rainfall events; or
3. The Ep in the receiving water channel shall approximate one (1), as demonstrated by a
hydromodification analysis study approved by the Director.
(Ord. 2013 -0044 § 5, 2013.)
12.84.450 LID Plan Review.
A. Compliance with the LID and hydromodification control standards of this Chapter 12.84 shall be
shown through a LID plan review described in subsection B, below.
B. The applicant for any development project shall submit a LID plan to the Director for review and
approval that provides a comprehensive, technical discussion of how the development project will
comply with this Chapter 12.84 and the applicable provisions specified in the LID Standards Manual.
A deposit and fee to recover the costs associated with LID plan review shall be required. The time for
obtaining LID plan approval shall be as follows:
1. For subdivisions, the LID plan shall be approved prior to the tentative map approval;
2. For any development project requiring a conditional use permit ( "CUP ") or other discretionary
entitlement required under Title 22 of the Los Angeles County Code, the LID plan shall be
approved prior to the issuance of any such CUP or other discretionary entitlement; and
3. For all other development projects, the LID plan shall be approved prior to issuance of a grading
permit for such development project, or when no grading permit is required, prior to the
issuance of a building permit for such development project, or when no grading or building
permit is required, prior to the commencement of any development activity or as otherwise
Indicated In the non- discretionary land use approval.
(Ord. 2013 -0044 § 6, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
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Chapter 12.84 LOW IMPACT DEVELOPMENT STANDARDS
12.84.460 Additional Requirements.
Compliance with this Chapter 12.84 shall also require a development project to satisfy the
following:
A. All grading and /or site drainage plans for the development shall incorporate the features of the
approved LID plan described in subsection B of Section 12.84.450
B. Ongoing Maintenance.
1. The development project's LID and hydromodification control features shall be maintained and
shall remain operable at all times and shall not be removed from the project site unless and until
such features have been replaced with other LID or hydromodification control features in
accordance with this Chapter 12.84
2. Unless excused by the Director in his or her discretion, the owner of the subject development
project site shall prepare and obtain the Director's approval of an operation and maintenance
plan and monitoring plan for all LID practices and LID and hydromodification control features
incorporated into the project.
3. The owner of the subject development project site shall record a covenant or agreement,
approved as to form and content by the Director, in the office of the Los Angeles County
Registrar - Recorder /County Clerk indicating that the owner of the subject development project
site is aware of and agrees to the requirements in this subsection B. The covenant or
agreement shall also include a diagram of the development project site indicating the location
and type of each LID and hydromodification control feature incorporated into the development
project. The time to record such covenant or agreement shall be as follows:
a. For any subdivision, prior to final map approval; and
b. For any other development project, prior to issuance of a grading plan approval for the
development project, and when no grading plan approval is required, prior to the issuance
of building plan approval for the development project.
(Ord. 2013 -0044 § 7, 2013: Ord. 2008 -0063 § 1 (part), 2008.)
Los Angeles County, California, Code of Ordinances Page 8
ROSEMEAD CITY COUNCIL
STAFF REPORT
TO: THE HONORABLE MAYOR AND CITY COUNCIL
FROM: JEFF ALLRED, CITY MANAGER
DATE: MAY 12, 2015 !/
SUBJECT: ORDINANCE NO. 952 — SECOND READING: LOW IMPACT
DEVELOPMENT STANDARDS FOR STORMWATER MANAGEMENT
SUMMARY
On April 28, 2015, the City Council introduced Ordinance No. 952 Low Impact
Development Standards for Stormwater Management. This ordinance adopts, by
reference, Chapter 12.84 of the Los Angeles County Code entitled "Low Impact
Development Standards." Ordinance No. 952 is now before the City Council for its
required second reading for adoption. When adopting by reference an existing code, as
the City is doing here, California Government Code Section 50022.3 requires the holding
of a public hearing at the time of the second reading.
Staff Recommendation
It is recommended that the City Council:
1. Conduct a public hearing and receive public testimony; and
2. Adopt Ordinance No. 952 at its Second Reading
DISCUSSION
The City of Rosemead is a permittee under the Municipal Separate Storm Sewer (MS4)
permit, which was adopted by the California Regional Water Quality Control Board, Los
Angeles Region, on November 8, 2012. This permit contains all regulations and
requirements for subject cities in Los Angeles County for compliance with the National
Pollutant Discharge Elimination System (NPDES). Included in this MS4 Permit is the
requirement that each City adopt and implement a Low Impact Development Ordinance.
Low Impact Development (LID) is an approach to land development that works with
natural conditions of the land to manage stormwater as close to its source as possible.
LID employs principles such as preserving and recreating natural landscape features and
minimizing imperviousness to create functional site drainage that treats stormwater as a
resource rather than a waste product.
Many practices have been used to implement these principles such as bioretention
facilities, rain gardens, and permeable pavement. By implementing LID principles and
ITEM NUMBER:
City Council Meeting
May 12, 2015
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practices, water can be managed in a way that reduces the impact of built -out areas and
promotes the natural movement of water within a watershed. The intention of this
requirement of the MS4 permit is to have LID applied on a broad scale, which may help
to maintain or restore a watershed's hydrologic and ecological functions. The source
treatment and infiltration of this stormwater will prevent the pollution of various
waterbodies that occurs when this stormwater runs off into channels and ditches.
In order to comply with the LID Requirement of the MS4 Permit, staff is recommending
that the City Council adopt by reference Chapter 12.84 of the Los Angeles County Code,
entitled "Low Impact Development Standards ". The City has previously adopted a number
of LA County Codes, by reference, for incorporation into the City's municipal code,
including the LA County building, traffic, and health codes. The requirements outlined in
section 12.84 of the Los Angeles County Code are identical to the standards that the City
would need to develop, therefore, the development of a unique ordinance would be
redundant. Additionally, the County has adopted a comprehensive LID implementation
manual that mirrors the ordinance and this code has been vetted and approved for
compliance by the Regional Board. Also, Los Angeles County staff, through an existing
General Services Agreement, will provide ongoing inspection of LID related
improvements, therefore, it is beneficial that the ordinances be consistent. As 84 of the
88 cities in Los Angeles County are subject to the MS4 permit and must adopt an LID
ordinance, it is anticipated that many cities will adopt the County Code by reference.
The approved LID ordinance will require developers of the following projects to submit
and receive approval for an LID plan prior to the issuance of grading and building permits:
1. All new development projects involving one (1) acre or greater of disturbed area and
adding more than ten thousand (10,000) square feet of impervious surface area;
2. New industrial parks with ten thousand (10,000) square feet or more of surface area;
3. New commercial malls with ten thousand (10,000) square feet or more of surface area;
4. New retail gasoline outlets with five thousand (5,000) square feet or more of surface
area;
5. New restaurants with five thousand (5,000) square feet or more of surface area;
6. New parking lots with five thousand (5,000) square feet or more of impervious surface
area or with twenty -five (25) or more parking spaces;
7. New automotive service facilities with five thousand (5,000) square feet or more of
surface area;
8. New development located in or directly adjacent to or discharging directly to a
Significant Ecological Area, which will discharge stormwater runoff that is likely to
impact a sensitive biological species or habitat and create two thousand five hundred
(2,500) square feet or more of impervious surface area, and
9. Development that results in the creation or addition or replacement of either:
a. Five thousand (5,000) square feet or more of impervious surface area on a site
that had been previously developed as described in sections 1 -8 above; or
b. Ten thousand (10,000) square feet or more of impervious surface area on a
site that had been previously developed with a single family home.
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These LID plans will be reviewed and approved as a component of the existing plan check
process for development projects. It should be noted that in anticipation of these
requirements being enacted, many components of LID have already been included in the
plan check process.
PUBLIC NOTICE PROCESS
This item has been noticed through the regular agenda notification process.
Prepared By:
Submitted By:
Matth Ha kesworth
Assistant City Manager /Acting Director of Public Works
Attachments:
A. Ordinance No. 952 — Low Impact Development Standards
B. Los Angeles County Code Chapter 12.84 — Low Impact Development
Standards