HomeMy WebLinkAbout2024-06-17 I04 Post-Construction Stormwater Management_INTRO, 1ST READAGENDA ITEM:
CITY OF WAUKEE, IOWA
CITY COUNCIL MEETING COMMUNICATION
MEETING DATE: June 17, 2024
AGENDA ITEM:Consideration of approval of an ordinance to amend Chapter 103, Post-
Construction Stormwater Management, City of Waukee, Iowa, by amending
Section 103.02, Applicability and Procedure for Post-Construction
[introduction; first reading]
FORMAT:Ordinance
SYNOPSIS INCLUDING PRO & CON: Staff have determined that amendments to certain post
construction stormwater management requirements should be made to the existing requirements in
Waukee Ordinance Chapter 103 in order to comply with subsection 18 to Section 364.3 of the Iowa
Code (fka Senate File 455) and its effective date of July 1, 2024.
FISCAL IMPACT INCLUDING COST/BENEFIT ANALYSIS:
COMMISSION/BOARD/COMMITTEE COMMENT:
STAFF REVIEW AND COMMENT:
RECOMMENDATION: Approve the introduction and first reading of the ordinance in title only.
ATTACHMENTS: I. Proposed Ordinance
PREPARED BY: Rudy Koester
REVIEWED BY: Rudy Koester RK
PUBLIC NOTICE INFORMATION –
NAME OF PUBLICATION:
DATE OF PUBLICATION:
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ORDINANCE NO. ____
AN ORDINANCE TO AMEND CHAPTER 103, POST-CONSTRUCTION
STORMWATER MANAGEMENT, CITY OF WAUKEE, IOWA, BY AMENDING
SECTION 103.02, APPLICABILITY AND PROCEDURE FOR POST-CONSTRUCTION
AS SPECIFIED BELOW
WHEREAS, the City of Waukee has determined that amendments to certain post
construction stormwater management requirements should be made to the existing requirements in
the Ordinance Chapter 103 in order to comply with subsection 18 to Section 364.3 of the Iowa Code
(fka Senate File 455) and its effective date of July 1, 2024.
BE IT THEREFORE ORDAINED by the City Council of the City of Waukee:
Section 1. Waukee Municipal Code Chapter 103, Post-Construction Stormwater
Management, Section 103.02, Applicability and Procedure for Post-Construction, is hereby amended
by repealing section 103.02, Applicability and Procedure for Post-Construction, in its entirety and
replacing the section as follow:
§103.02 Applicability and Procedure for Post-Construction.
1.Installation of Facilities. Each applicant who is required to have coverage
under General Permit No. 2 for a site shall install post-construction
stormwater management facilities as set forth herein and as approved by the
City during site plan, platting, or construction plans.
2.Maintenance of Facilities. Each applicant or its successor person(s) or entity
shall be responsible for maintaining all stormwater management facilities or
BMPs as approved by the City.
3. Proof of Construction of Stormwater Facilities.
A.For sites equal to or greater than one acre, each applicant must provide
to the City as-built plans detailing dimensions and elevations as well
as a certification that stormwater management facilities or BMPs were
built as part of the approved development that includes the site.
B.For sites less than one acre that are part of a common plan of
development and for which the applicant establishes that stormwater
management facilities or BMPs were or will be built to address all
properties (either collectively or individually) within the development,
each applicant must provide to the City a copy of the notice of
discontinuation for General Permit No. 2 applicable to the property.
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4. Adoption of Specifications. In 2024, the Iowa Legislature passed new
regulations that limit how cities and counties can enforce local stormwater post
construction requirements. The City hereby acknowledges the new Section
364.3(18) of the Code of Iowa relating to the regulation of topsoil and storm
water at construction sites and incorporates limits into the Waukee Standard
Specifications for Public Improvements for management of stormwater.
5. Adoption of Preferred Specifications. The City hereby adopts the Iowa
Stormwater Management Manual (ISWMM) and the Waukee Standard
Specifications for Public Improvements for management of stormwater. The
ISWMM is written as a guideline recommending certain techniques and
advising against others in order to accomplish goals related to managing water
volume and quality. Therefore, where the ISWMM states a design element or
technique is “essential” it is required by the City. Where ISWMM states a
design element or technique is “target” such design element or technique is
desired by the City and every effort shall be made to accomplish. Where
ISWMM states a given design element or technique is “advisory” this design
element or technique shall not be used within the City.
6. Alternative Specifications. In cases where Section 364.3(18) of the Code of
Iowa does not speak to a stormwater issue, such as sizing or installation of
pipes, the City follows the Iowa Statewide Urban Design and Specifications
(SUDAS), the Waukee Standard Specifications for Public Improvements or the
Iowa River Restoration Toolbox streambank stabilization guide as applicable.
7. Drainage and Detention of Treatment Areas. Each applicant must include in the site
design those stormwater management facilities or BMP that will convey drainage
through the property to one or more detention or treatment areas such that no
development shall cause downstream property owners, watercourses, channels, or
conduits to receive stormwater runoff from the proposed development site at a peak
flow rate greater than that allowed by the policy or standard in effect at the time of
approval of the development unless such requirements are waived by the City.
Nothing contained herein shall prohibit the City from changing the policies or
standards in the future, or from requiring the site to comply with the new
requirements.
8. Compliance with City, State, and Federal Permit Requirements. Each applicant
shall comply with all other applicable City, State, or federal permit requirements as
they apply to the City or to the property.
9. Regional Detention Facilities. At the discretion of the City, the applicant may satisfy
the post-construction stormwater management requirements by ensuring the
conveyance of the stormwater discharge from the property to a regional detention
facility. For purposes of this chapter, a “regional detention facility” shall be wet or
dry detention basins, which are designed to accept stormwater runoff from two or
more sites that are required to obtain a State NPDES General Permit No. 2 and that
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otherwise complies with all City, State, or federal permit requirements as they apply
to stormwater management requirements for those sites.
10. New Development. Any new development of land adding more than 10,000
square feet of new impervious surface shall provide stormwater management as
outlined in Section 364.3(18) of the Code of Iowa and the Waukee Standard
Specifications for Public Improvements. This threshold is a cumulative amount
of new square footage and may be reached over time in increments. At such time
that a development site exceeds 10,000 cumulative square feet of new impervious
surface the site will be required to come into compliance with this chapter.
11. Redevelopment.
A. Any redevelopment of land adding more than 10,000 square feet of new
impervious surface but disturbing less than 50 percent of the site shall provide
stormwater management as outlined in Section 364.3(18) of the Code of Iowa
and the Waukee Standard Specifications for Public Improvements. This
threshold is a cumulative amount of new square footage and may be reached
over time in increments. At such time that a development site exceeds 10,000
cumulative square feet of new impervious surface the site will be required to
come into compliance with this chapter.
B. Any redevelopment of land disturbing more than 50 percent or more of the
site shall provide stormwater management as outlined in Section 364.3(18) of
the Code of Iowa and the Waukee Standard Specifications for Public
Improvements.
12. City Projects. Stormwater management standards per the ISWMM guidelines for
water quality and channel protection shall apply to all City projects including new
City parks and buildings.
13. Exemptions. The following activities shall be exempted from meeting the
stormwater management standards of this chapter:
A. New development or redevelopment adding less than 10,000 square feet of
new impervious surface and if in compliance with a previously approved
stormwater management plan.
B. Removal and replacement of impervious surface exactly matching location
and area of existing impervious surface.
C. Logging or agricultural activity that is consistent with an approved soil
conservation plan or timber management plan prepared or approved by the
appropriate agency, as applicable.
D. Additions or modifications to single family structures.
E. Repairs to any stormwater management BMP deemed necessary by the
City.
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F. Linear reconstruction projects, such as road construction, that are not
associated with a larger planned development.
Section 2. Repealer. All ordinances or parts of ordinances in conflict with the provisions of
this ordinance are hereby repealed.
Section 3. Severability Clause. If any section, provision or part of this ordinance shall be
adjudged invalid or unconstitutional, such adjudication shall not affect the validity of the ordinance
as a whole or any section, provision, or part thereof not adjudged invalid or unconstitutional.
Section 4. Effective Date. This ordinance shall be in effect upon its final passage, approval
and publication as provided by law.
Passed by the Council the day of ________, 2024, and approved this _____ day of ,
2024.
Courtney Clarke, Mayor
Attest:
Rebecca D. Schuett, City Clerk