2571ORDINANCE NO.2571
AN ORDINANCE CREATING CHAPTER 13.035 OF THE MOSES LAKE MUNICIPAL
CODE ENTITLED "CONSTRUCTION AND POST CONSTRUCTION STORMWATER
RUNOFF"
THE CITY COUNCIL OF THE CITY OF MOSES LAKE,WASHINGTON ORDAINS AS FOLLOWS:
Section 1.Chapter 13.035 of the Moses Lake Municipal Code entitled "Construction and Post Construction
Stormwater Runoff1 is created as follows:
13.035.010 Potential Discharge to Moses Lake:
A.All public and private construction projects that disturb one or more acres,and all
construction projects that disturb less than one acre that are part of a common plan of
development or sale that will cause a potential discharge to Moses Lake shall meet the
applicable requirements contained in Chapter Two of the Stormwater Management
Manual forEastern Washington.Furthermore,the property owner shall obtain coverage
for the project under the Department of Ecology's "General NPDES Permit for
Stormwater Discharges Associated with Construction Activities."
B.An erosivity waiver to allow construction activity to proceed without a Stormwater Pollution
Prevention Plan may be authorized by the Municipal Services Director.Erosivity waivers are
not valid without written authorization from the Municipal Services Director. Erosivity waivers
require that all of the following conditions are met prior to approval.
1.The construction project will result in the disturbance of less than five acres,and the site
is not a portion of a common plan of development or sale that will disturb more than five
acres.
2.The project's rainfall erosivity factor is less than five during the period of proposed
construction activity,as calculated using the Texas A&M University online rainfall
erosivity calculator.The calculator may be accessed at http://ei.tamu.edu/.The period
of construction activity is defined as the period that begins with initial earth disturbance
and ends with final stabilization.Final stabilization shall be as verified by the Municipal
Services Director.
3.The site or facility has not been declared a significant contributor of pollutants,and
construction activities that will not result in non-stormwater discharges.
4.The Construction Site Operator submits an application 10 days prior to commencing land
disturbing activities.The written application from the construction site operator for an
erosivity waiver shall include a summary of the project information used in calculating the
project's rainfall erosivity factor.Furthermore,the application shall contain a certified
statement that the Construction Site Operatorwill complywith applicable local stormwater
requirements,and will implement appropriate erosion and sediment control Best
Management Practices (BMPs)to prevent violations of water quality standards.
13.035.020 Access:Access for inspections for all private stormwater systems that discharge to the City's
stormwater system shall be allowed as follows.
A.The construction site operator shall allow access for city and the Department of Ecology staff
to inspect the construction-phase stormwater BMPs.
ORDINANCE NO.2571PAGE2 .July 13,2010
B.The property owner shall allow city staff access to the property to inspect the post
construction-phase BMPs;or the property owner shall provide annual certification by a
qualified third party,approved by the Municipal Services Director,to verify that adequate
maintenance has been performed,and to verify that the facilities are operating as designed
to protect water quality.
13.035.030 Stormwater System Design:Stormwater systems shall be designed for a 25-year,24-hour
storm event using the SCS Curve Method as outlined in Stormwater Management Manual
for Eastern Washington.Public stormwater systems shall be designed to retain stormwater
within approved stormwater appurtenances,and outside of travel lanes.Private stormwater
systems shall be designed to retain all stormwater within the originating property.
13.035.040 Severability:If any provision of this chapter or its application to any person or circumstance
is held invalid,the remainder of this chapter or the application of the provisions of this chapter
are declared to be severable,and shall remain in full force and effect.
Section 2.This ordinance shall take effect and be in force five (5)days after its passage and publication of
its summary as provided by law.
Adopted by the City Council and signed by its Mayor on July 13,2010.
Jorrfcene,Mayor
ATTEST:
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Ronald R.Cone,Finance Director
APPROVED AS TO FORM:
James A.Whitaker,City Attorney
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