Chapter 13.33 STORM WATER DRAINAGE UTILITY

The purpose of this chapter is to protect, maintain, and enhance the public health, safety, and general welfare by establishing minimum requirements and procedures to control the adverse impact associated with increased runoff and reduced water quality and to comply with state and federal storm water management requirements. (Ord. 3453 § 2, 2009).

13.33.020 Definitions.

Words and phrases used in this chapter have the meaning set forth in this section:

A. “Appendix 1” refers to Appendix 1 of the Western Washington Phase II Municipal Stormwater Permit which contains the minimum technical requirements for development and redevelopment.

B. “Biofiltration facility” means the simultaneous processes of filtration, infiltration, absorption and biological uptake of pollutants in storm water that take place when runoff flows over and through vegetated treatment facilities.

C. “Best management practices (BMPs)” are the schedules of activities, prohibitions of practices, maintenance procedures, and structural and/or managerial practices approved by the Washington State Department of Ecology that, when used singly or in combination, prevent or reduce the release of pollutants and other adverse impacts to waters of Washington State.

D. “Computations” means calculations, including coefficients and other pertinent data, made to determine the rates of flow for storm water plans, with units given in cubic feet per second.

E. “Critical areas” shall mean, at a minimum, areas that include wetland areas with a critical recharging effect on aquifers used for potable water, fish, and wildlife habitat conservation areas, frequently flooded areas, geologically hazardous areas, including unstable slopes and associated areas and ecosystems. See Chapter 15.40 MVMC.

F. “Current conditions” means the state, status, or condition of the subject property at the time a legally sufficient and complete permit application is made for those regulated activities described in MVMC 13.33.030, which may include existing buildings, impervious areas, and topography as is.

G. “Design storm” refers to a prescribed hyetograph and total precipitation amount (for a specific duration and recurrence frequency) used to estimate runoff for a hypothetical storm of interest or concern for the purposes of analyzing existing drainage, designing new drainage facilities, or assessing other impacts of a proposed project on the flow of surface water. A hyetograph is a graph of percentages of total precipitation for a series of time steps representing the total time during which the precipitation occurs.

H. “Detention facilities” means an above or below ground facility, such as a pond or tank, that temporarily stores storm water runoff and subsequently releases it at a slower rate than it is collected by the drainage facility.

I. “Developed conditions” means the state, status, or condition of the subject property at the time the proposed project has been completed, which may include existing buildings, impervious areas, and topography as is.

J. “Developer” means the individual(s) or corporation(s) or governmental agency(ies) applying for the permits or approvals described in MVMC 13.33.030.

K. “Development” means new development, redevelopment, or both. See definitions for each.

L. “Developmental coverage” means all developed surface areas within the subject property including, but not limited to, rooftops, driveways, carports, accessory buildings, parking areas, and any other impervious surfaces. During construction, “development coverage” includes the above in addition to the full extent of any alteration of previously occurring soils, slope, or vegetation due to grading, temporary storage, access areas, or any other short-term causes.

M. “Drainage area” means the watershed contributing water runoff to and including the subject property.

N. “Drainage facility” refers to structures or features, natural or artificial, that convey, treat, and/or abate surface water runoff including, but not limited to, detention facilities, retention facilities, and drainage retention/abatement facilities.

O. “Drainage site” means a geographical area that serves a common or combined use including, but not limited to, shopping malls and strips, condominiums, apartment complexes, office parks and housing tracts. A site may include one or more parcels and/or include one or more buildings. Also see “Development.”

P. “Drainage system” refers to the drainage system consisting of natural and artificial systems that convey surface water within the city of Mount Vernon. This system includes pipes, culverts, ditches, open channels, swales, streams, lakes, rivers, ponds, and detention and retention ponds, as well as other types of conveyance, storage and infiltration facilities. Depending on its context, a drainage system refers to either the public drainage system or a private drainage system, or both.

Q. “Drainage treatment/abatement facilities” means any facilities installed or constructed in conjunction with a drainage plan for the purpose of treating urban runoff to improve water quality.

R. “Effective impervious surface” means those impervious surfaces that are connected via sheet flow, or discrete conveyance to a drainage system. Impervious surfaces are considered ineffective if:

1. The runoff is dispersed through at least 100 feet of native vegetation in accordance with BMP T5.30, Full Dispersion, as described in Chapter 5 of Volume V of the Stormwater Management Manual for Western Washington.

2. Residential roof runoff is infiltrated in accordance with Downspout Full Infiltration – Drywells in BMP T5.10A in Volume III of the Stormwater Management Manual for Western Washington; or

3. Approved continuous runoff modeling methods indicate that the entire runoff file is infiltrated.

S. “Environmentally critical areas” means critical areas defined by Chapter 15.40 MVMC to which this chapter shall apply.

T. “Hard surface” means an impervious surface, a permeable pavement, or a vegetated roof.

U. “Illicit connection” means any infrastructure connection to the MS4 that is not intended, permitted or used for collecting and conveying storm water or non-storm water discharges allowed as specified in MVMC 13.33.080. Examples include sanitary sewer connections, floor drains, channels, pipelines, conduits, inlets, or outlets that are connected directly to the MS4.

V. “Illicit discharge” means any discharge to an MS4 that is not composed entirely of storm water or of non-storm water discharges allowed as specified in MVMC 13.33.080.

W. “Impervious surface” means: (1) a nonvegetated surface area that either prevents or retards the entry of water into the soil mantle as under natural conditions prior to development, (2) a nonvegetated surface area which causes water to run off the surface in greater quantities or at an increased rate of flow from the flow present under natural conditions prior to development. Common impervious surfaces include, but are not limited to, rooftops, walkways, patios, driveways, parking lots or storage areas, concrete or asphalt paving, gravel roads, packed earthen materials, and oiled, macadam, or other surfaces that similarly impede the natural infiltration of storm water. Open, uncovered retention/detention facilities shall not be considered as impervious surfaces for the purposes of determining whether the thresholds for application of minimum requirements are exceeded. Open, uncovered retention/detention facilities shall be considered impervious surfaces for purposes of runoff modeling and calculation.

X. “Land-disturbing activities” means any activity that results in a change in the existing soil and/or land cover (both vegetative and nonvegetative) and/or the existing soil topography. Land-disturbing activities include, but are not limited to, clearing, grading, filling, and excavation. Compaction that is associated with stabilization of structures and road construction shall also be considered a land-disturbing activity. Vegetation maintenance practices, including landscape maintenance and gardening, are not considered a land-disturbing activity. Storm water facility maintenance is not considered land-disturbing activity if conducted according to established standards and procedures.

Y. “Low impact development (LID)” means a storm water and land use management strategy that strives to mimic predisturbance hydrologic processes of infiltration, filtration, storage, evaporation and transpiration by emphasizing conservation, use of on-site natural features, site planning, and distributed storm water management practices that are integrated into a project design.

Z. “Municipal separate storm sewer system” (MS4) means a conveyance, or system of conveyances, including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains:

1. Owned or operated by a state, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to state law) having jurisdiction over disposal of wastes, storm water, or other wastes, including special districts under state law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under Section 208 of the Clean Water Act that discharges to waters of Washington State;

2. Designed or used for collecting or conveying storm water;

3. Which is not a combined sewer;

4. Which is not part of a publicly owned treatment works (POTW) as defined at 40 CFR 122.2; and

5. Which is defined as “large” or “medium” or “small” or otherwise designated by the Washington State Department of Ecology pursuant to 40 CFR 122.26.

AA. “Native vegetation” means vegetation comprised of plant species, other than noxious weeds, that are indigenous to the coastal region of the Pacific Northwest and which reasonably could have been expected to occur naturally on the site. Examples include trees such as Douglas fir, western hemlock, western red cedar, alder, big-leaf maple, and vine maple; shrubs such as willow, elderberry, salmonberry, and salal; and herbaceous plants such as sword fern, foam flower, and fireweed.

BB. “Natural location” of drainage systems refers to the location of those channels, swales, and other natural conveyance systems as defined by the first documented topographic contours existing for the subject property, either from maps or photographs or such other means as appropriate.

CC. “New development” means land-disturbing activities, including land clearing and forest practices regulated by Chapter 15.18 MVMC; structural development, including construction or installation of a building or other structure; creation of hard surfaces; and subdivision, short subdivision, and binding site plans, as defined and applied in Chapter 58.17 RCW. Projects meeting the definition of redevelopment shall not be considered new development.

DD. “Permit” means the most current version of the city’s Western Washington Phase II Municipal Stormwater Permit, effective 2013, including modifications issued through the expiration date of the permit. Appendix 1 of this permit contains the minimum technical requirements for new development and redevelopment.

EE. “Planner” means city of Mount Vernon community and economic development director or his/her designee.

FF. “Permanent storm water quality control plan (PSQCP)” means a plan that includes permanent BMPs for the control of pollution from storm water runoff after construction and/or land-disturbing activity has been completed.

GG. “Pollutant” shall mean any substance which, when added to water, would cause contamination or other alteration of the physical, chemical, or biological properties of waters of the state, including change in temperature, taste, color, turbidity, or odor of the waters, or such discharge of any liquid, gaseous, solid, radioactive, or other substance into any waters of the state, as will or is likely to create a nuisance or render such waters harmful, detrimental, or injurious to the public health, safety, or welfare, or to domestic, commercial, industrial, agricultural, recreational, or other legitimate beneficial uses, or to livestock, wild animals, birds, fish, or other aquatic life.

HH. “Predeveloped” means the native vegetation and soils that existed at a site prior to the influence of Euro-American settlement. The predeveloped condition shall be assumed to be forested land cover unless reasonable, historic information is provided that indicates that the site was prairie prior to settlement.

II. “Private drainage system” means drainage systems located on private property and designed to discharge directly as through pipes, channels, etc., or indirectly as sheet flow, subsurface flow, etc., into the city’s drainage system.

JJ. “Public drainage system” means that portion of the drainage system of the city located on public right-of-way, easement or dedicated tract, or other property owned by the city and those portions of private drainage systems assumed by the city.

KK. “Receiving bodies of water” means bodies of water or surface water systems to which surface runoff is discharged via a point source of storm water or via sheet flow. Receiving water may also be groundwater to which surface runoff is directed by infiltration.

LL. “Redevelopment” means that on a site that is already substantially developed (i.e., has 35 percent or more of existing hard surface coverage), the creation or addition of hard surfaces; the expansion of a building footprint or addition or replacement of a structure; structural development including construction, installation, or expansion of a building or other structure; replacement of hard surface that is not part of a routine maintenance activity; and land-disturbing activities.

MM. “Retention/detention facilities” means a type of drainage facility designed either to hold water for a considerable length of time and then release it by evaporation, plant transpiration, and/or infiltration into the ground; or to hold surface water and storm water runoff for a short period of time and then release it to the surface and/or storm water management system.

NN. “Storm water plan” means a plan approved by the city of Mount Vernon that includes a small parcel or large parcel storm water plan and/or a permanent storm water quality control plan.

OO. “Stormwater Management Manual for Western Washington” means the five-volume technical manual (Publication No. 19-10-021) prepared and published by the Washington State Department of Ecology in 2019, including any subsequent updates or amendments.

PP. “Subject property” means the tract of land which is the subject of the permit and/or approval action as defined by the full legal description of all parcels involved in the proposed development.

QQ. “Uncontaminated” means water that has not come into contact with illicit discharges or other pollutants.

RR. “Washington State Department of Transportation Highway Runoff Manual” means the Highway Runoff Manual prepared and published by the Washington State Department of Transportation in 2019 (Publication No. M31-16.05) and any subsequent updates approved by Ecology as equivalent to the Department of Ecology’s Stormwater Management Manual for Western Washington. The Highway Runoff Manual provides guidance to direct the planning and design of storm water management facilities for existing and new Washington State highways, rest areas, park-and-ride lots, ferry terminals, and highway maintenance facilities throughout the state. (Ord. 3852 § 3, 2022).

13.33.030 Regulated activities.

All new development, redevelopment and other activities listed below shall comply with the conditions of this chapter.

A. Creation or alteration of new or additional hard surfaces;

B. New development;

C. Redevelopment;

D. Activities that require a fill and grade permit;

E. Activities that require a building permit;

F. Subdivision approval;

G. Short subdivision approval;

H. Activities that require a commercial, industrial, or multifamily site plan approval;

I. Planned unit development approval;

J. Development or redevelopment within or adjacent to critical areas per Chapter 15.40 MVMC;

K. Activities that require a conditional use permit;

L. Activities that require a substantial development permit pursuant to Chapter 90.58 RCW (Shoreline Management Act);

M. Activities that require a permit pursuant to Chapter 15.18 MVMC;

N. Any activity that may fall within and be subject to regulation by the most current version of the city’s permit and the Stormwater Management Manual for Western Washington. (Ord. 3700 § 5, 2016).

13.33.040 Exemptions.

The public works director may determine whether or not a proposed project is exempt from the provisions of this chapter. Exemptions shall be consistent with all city, state, and federal requirements and may include those set forth in the thresholds, definitions, minimum requirements and exceptions, adjustment and variance criteria found in Appendix I of the permit. The following activities shall be exempt:

A. Development undertaken by the Washington State Department of Transportation in state highway rights-of-way that is regulated and meets the requirements of Chapter 173-270 WAC, the Puget Sound Highway Runoff Program, is exempt from the requirements of this chapter.

B. Commercial agriculture, including only those activities conducted on lands defined in RCW 84.34.020(2), and production of crops or livestock for wholesale trade.

C. Forest practices regulated under WAC Title 222, except for Class IV general forest practices, as defined in WAC 222-16-050, that are conversions from timber land to other uses.

D. Road maintenance practices identified as exempt in Appendix 1 of the NPDES permit.

E. Underground utility projects that replace the ground surface with in-kind material or materials with similar runoff characteristics are only subject to minimum requirement No. 2, Construction Stormwater Pollution Prevention, as defined in Appendix 1 of the NPDES permit.

F. Requests for exemption shall be filed in writing with the public works director, and shall adequately detail the basis for granting an exemption.

G. The decision of the public works director may be appealed to the city council by filing written notice of appeal with the city finance director within 10 days of service of the public works director’s written decision. The cost of the appeal shall be $100.00. (Ord. 3700 § 6, 2016).

13.33.050 General provisions.

Storm water management measures shall be designed, constructed, and maintained in accordance with the standards and specifications as set forth in the thresholds, definitions, minimum requirements and exceptions, adjustment, and variance criteria found in Appendix I of the permit, the Stormwater Management Manual for Western Washington, and the most current version of the city’s engineering standards.

A. All storm water management measures shall be analyzed consistent with the requirements of the Stormwater Management Manual, using the continuous modeling program: the Western Washington Hydrology Model, hereinafter referred to as WWHM, or an alternative continuous modeling program allowed by the manual, or as otherwise approved by the public works director.

B. The public works director may determine whether or not a proposed public roadway project may be designed constructed, and maintained in accordance with the standards and specifications as set forth in the most recent version of the Washington State Department of Transportation Highway Runoff Manual approved as equivalent to the Stormwater Management Manual for Western Washington. (Ord. 3700 § 7, 2016).

13.33.060 General storm water requirements.

A. Minimum requirements for storm water management include the following items as further described in the permit, Appendix I:

1. Preparation of storm water site plans;

2. Construction storm water pollution prevention plan (SWPPP);

3. Source control of pollution;

4. Preservation of natural drainage systems and outfalls;

5. On-site storm water management;

6. Runoff treatment;

7. Flow control;

8. Wetland protection;

9. Operations and maintenance.

Requirement 2 applies to all new development and redevelopment projects. The applicability of minimum requirements of the permit varies depending on the type and size of the project. Appendix 1 of the permit identifies thresholds that determine the applicability of the minimum requirements to different new development and redevelopment projects.

B. New Development.

1. All new development shall be required to comply with subsection (A)(2) of this section. In addition, the following two conditions will comply with subsections (A)(1) through (5) of this section:

a. Project creates or adds 2,000 square feet, or greater, of new, replaced, or new plus replaced hard surface area.

b. Project has land-disturbing activity of 7,000 square feet or greater.

2. The following three new development projects shall comply with subsections (A)(1) through (9) of this section:

a. Project creates or adds 5,000 square feet, or more, of new plus replaced hard surface area.

b. Project converts three-quarters acre, or more, of native vegetation to lawn or landscaped areas.

c. Project converts two and one-half acres, or more, of native vegetation to pasture.

C. Redevelopment.

1. The following redevelopment shall comply with subsections (A)(1) through (5) of this section for the new and replaced impervious surfaces and the land disturbed:

a. The new, replaced, or total of new plus replaced impervious surfaces is 2,000 square feet or more.

b. Seven thousand square feet or more of land-disturbing activities.

2. The following redevelopment shall comply with subsections (A)(1) through (9) of this section for the new impervious surfaces and converted pervious areas:

a. Adds 5,000 square feet or more of new impervious surfaces.

b. Converts three-quarters acre, or more, of native vegetation to lawn or landscaped areas.

c. Converts two and one-half acres, or more, of native vegetation to pasture.

D. Additional Storm Water Requirements for Development and Redevelopment.

1. Retention, detention, infiltration or LID facilities serving private property shall not be located within dedicated public road right-of-way.

2. All drainage easements granted to the city within a subject property shall be at least 20 feet in width for operation and maintenance of open channel or closed system installation.

3. As-built plans and pond performance reports shall be submitted to the city prior to final approval/acceptance of said project.

4. Private Ownership of Storm Water Facilities. Owners of private storm water systems and facilities that collect, convey, treat and/or infiltrate runoff are responsible for the operation and maintenance of those facilities.

5. City Ownership of Storm Water Facilities. Storm water systems and facilities that are public improvements and that are to be owned and maintained by the city shall, after satisfactory completion of the storm water facilities, post and maintain a maintenance bond as required for a final plat for subdivisions under MVMC 16.12.020 regardless if such public improvement is a condition to subdivision or other land use activity. (Ord. 3700 § 8, 2016).

13.33.070 Low impact development.

The city of Mount Vernon requires the use of low impact development best management practices (BMPs) in the control of storm water where feasible. LID measures shall be implemented for development and redevelopment projects in accordance with Appendix 1 of the permit and the Stormwater Management Manual for Western Washington.

LID system designs shall be prepared by a registered professional engineer licensed in the state of Washington and experienced in LID design and be certified by the preparing engineer as feasible and safe for the intended application and meeting all state and federal requirements for such LID facilities.

A registered professional engineer licensed in the state of Washington and experienced in LID design is also required to certify that the facility has been constructed as shown on the “as-built” plans and meets approved plans and specifications. (Ord. 3700 § 9, 2016).

13.33.080 Illicit discharges.

A. Storm Water Discharges to Sanitary and Combined Sewers. The public works director may approve discharges of storm water to a public combined sewer or sanitary sewer if other methods of controlling pollutants in the discharge are not adequate and the discharge will not harm the environment. The public works director may condition approval of such a discharge on compliance with requirements to control, reduce, or treat discharges prior to their entry into the public combined sewer or sanitary sewer.

B. Discharges Prohibited to Public Drainage Control Systems. All illicit discharges, as defined in MVMC 13.33.020 and subsection C of this section, made either directly or indirectly to a public drainage control system are prohibited and constitute a violation of this chapter. Enforcement actions and penalties are described in MVMC Title 19.

C. Illicit Discharges Defined. Except as provided in subsection D of this section, all discharges that are not composed of storm water are illicit discharges.

The following is a partial list, provided for informational purposes only, of common substances that are illicit discharges when allowed to enter a public drainage control system: solid waste; human and animal waste; antifreeze, oil, gasoline, grease and other automotive and petroleum products; flammable or explosive materials; metals in excess of naturally occurring amounts, whether in liquid or solid form; chemicals not normally found in uncontaminated water; solvents and degreasers; painting products; drain cleaners; commercial and household cleaning materials; pesticides; herbicides; fertilizers; acids; alkalis; ink; steam-cleaning waste; laundry waste; soap; detergent; ammonia; chlorine; chlorinated swimming pool or hot tub water (unless dechlorinated to a total residual chlorine concentration of 0.1 ppm or less and pH-adjusted and reoxygenized as necessary); volumetrically and velocity controlled to prevent re-suspension of sediments in the MS4 and thermally controlled to prevent an increase in temperature of the receiving water; swimming pool cleaning wastewater and filter backwash; domestic or sanitary sewage; animal carcasses; food and food waste; yard waste; dirt; sand; and gravel (except for traction grit).

D. Permissible Discharges. Discharges from the sources listed below shall only be illicit discharges if the public works director determines that the type of discharge, whether singly or in combination with others, is causing or contributing to a water quality violation, or is causing or contributing to a water quality problem, such as those which contain more contamination than is acceptable in the city, or which contain a type of contamination that is more toxic or is otherwise a more serious problem than typical discharges in the city: potable water sources; natural uncontaminated surface water; natural uncontaminated groundwater; air conditioning condensation; natural springs; uncontaminated water from crawl space pumps; uncontaminated agricultural runoff that is commingled with urban storm water; flows from riparian habitats and wetlands; and discharges from footing drains and other subsurface drains approved by the public works director or where approval is not required.

E. Exemptions. Discharges resulting from emergency firefighting activities. Discharges from potable water sources, including water line flushing, hyperchlorinated water line flushing, fire hydrant system flushing, and pipeline hydrostatic test water are only permissible if dechlorinated to a concentration of 0.1 ppm or less, pH-adjusted, if necessary, and volumetrically and velocity-controlled to prevent resuspension of sediments in the MS4. Street and sidewalk wash water, water used to control dust, and routine external building wash down that does not use detergents.

F. Testing for Illicit Discharges. When the public works director has reason to believe that any discharge is an illicit discharge, the public works director may require a responsible party to sample and analyze the discharge at the responsible party’s expense, and to provide an analysis of the data to the public works director. The public works director may conduct such sampling and analysis and recover the costs from a responsible party in an enforcement proceeding. When the discharge is likely to contain illicit discharges on a recurring basis, the public works director may conduct, or may require the responsible party to conduct, ongoing monitoring at the responsible party’s expense. (Ord. 3700 § 10, 2016).

13.33.090 Administration.

The public works director shall have the authority, with the approval of the city council, to develop and implement administrative procedures to administer and enforce this chapter including, but not limited to, fees which shall be uniform within any class of applicants and based on actual or approximated expense to the city for review, inspection, and administration; and surety and cash bonds for construction, maintenance, and performance. (Ord. 3453 § 10, 2009).

13.33.100 Review and approval.

A. The requirements of this chapter may be modified at the discretion of the public works director when more information is deemed necessary for proper review.

B. The public works director may approve, conditionally approve, or deny an application for activities regulated by this chapter.

C. All storm drainage documents prepared in connection with any of the permits and/or approvals listed in MVMC 13.33.030 shall be submitted for review by, and approval of, the public works director. (Ord. 3453 § 11, 2009).

13.33.110 Inspection – Construction.

A. All activities regulated by this chapter shall be inspected by the public works director and/or building department. Projects shall be inspected at various stages of the work to determine that adequate control is being exercised. Stages of work subject to inspection include, but are not limited to: preconstruction; installation of erosion control BMPs; land-disturbing activities; installation of utilities, landscaping, or retaining walls; and completion of project. When required by the public works director, a special inspection and/or testing shall be performed.

B. At the time of approval of the construction permit for the subject property, a schedule for inspection to ensure proper review of construction and facilities will be established by the public works director consistent with Section S.5.C.4.b. of the Permit. (Ord. 3453 § 12, 2009).

13.33.115 Inspections – Local source control.

A. All business activities regulated by this chapter shall be inspected by the designees appointed by the public works and/or the development services directors. Projects shall be inspected at various stages of the work to determine that adequate control is being exercised. Stages of work subject to inspection include but are not limited to: preconstruction; installation of source control BMPs, and final inspection for construction approval.

B. All businesses identified by the city as potential pollutant-generating sources must utilize source control BMPs as per the latest Ecology Stormwater Manual approved for use by the city. Businesses must implement structural and/or treatment BMPs if operational BMPs are not sufficient, as determined by the public works and/or development services directors or their designees. (Ord. 3852 § 4, 2022).

13.33.120 Modification of facilities during construction.

The public works director may require that the construction of drainage facilities and associated project designs be modified or redesigned if conditions occur or are discovered which were not considered or known at the time that the permit or approval was issued, such as uncovering unexpected soil and/or water conditions, weather generated problems, or undue materials shortages. Any such modifications made during the construction of drainage control facilities shall be in accordance with all city, state and federal requirements and shall be shown on the final approved drainage plan, a revised copy of which shall be provided to the public works director for filing. (Ord. 3453 § 13, 2009).

13.33.130 City acceptance of storm water facilities.

Maintenance of all drainage facilities constructed or modified by a proposed project is the responsibility of the property owner and shall be conducted in accordance with Section S.5.C.4.c. of the Permit. The city, at its discretion, may assume maintenance of drainage facilities constructed for formal plat subdivisions. (Ord. 3453 § 14, 2009).

13.33.140 Consultant and consultant fees.

The public works director may utilize outside consultants, the cost of which shall be borne by the developer, for plan review and inspection. In such cases, the developer shall make a deposit in advance and supplement it as necessary to pay for plan review and inspection costs. (Ord. 3453 § 15, 2009).

13.33.150 Prohibited acts.

It shall be prohibited, and in violation of this chapter, for any person or entity to:

A. Cause or permit litter, trash, rubbish, or debris to enter the public drainage system or any private drainage system which may directly or indirectly discharge to the city’s drainage system.

B. As provided in MVMC 13.33.080, for any person or entity to cause or permit pollutants to enter any private drainage system or the public drainage system, including, but not limited to, oils and petroleum products, paints, and paint thinners, pesticides, fertilizers, soaps, detergents, washing wastes and any pollutants found on the following lists, as now or hereafter amended, herein adopted as part of this chapter by reference:

1. Discarded Chemicals List of WAC 173-303-9903.

2. Toxic Dangerous Waste List of WAC 173-303-101.

3. Dangerous Waste Sources List of WAC 173-303-9904.

4. Dangerous Waste Constituents List of WAC 173-303-9905.

5. Dangerous Waste Mixtures List of WAC 173-303-084.

6. Persistent Dangerous Waste List of WAC 173-303-102.

C. Cause any damage to any drainage facilities of any private drainage system or the public drainage system.

D. Cause or permit horses, cattle, or other domestic animals to enter any watercourses or wetlands that are part of the drainage system of the city. Storm water for stables, pastures, and other animal enclosures shall be diverted or treated so as to prevent polluted drainage waters from entering the drainage system of the city.

E. Cause or permit grading, clearing, filling or other land surface changes to take place in such a way as to allow drainage from the property to carry any suspended or dissolved matter into the drainage system of the city.

F. Cause or permit any work that would result in the transmission of silt, pollution materials, or other foreign substances from one part of the drainage system to another.

G. Discharge any waters or in any way cause the temperature of the water discharged from the property to exceed by more than five degrees Fahrenheit the temperature of the nearest receiving waters.

H. Introduce into the drainage system any liquid or solid foreign substances of biodegradable or other nature which shall cause the water quality to degrade from the applicable water quality standards of the state of Washington (Chapter 173-201A WAC).

I. No obstructions shall be placed or allowed that would prohibit the free passage of fish under all flow conditions, unless approved by the Department of Fish and Wildlife. (Ord. 3453 § 16, 2009).

13.33.160 Monitoring facilities.

A. The public works director may require, during the design and/or construction phase, that an owner shall provide, maintain, and operate, at the owner’s own expense, a monitoring facility to allow inspection, sampling, and flow measurement of all discharges into the city’s drainage, as required by the public works director to assure compliance with this chapter. Each monitoring facility shall be situated as approved by the public works director so as to provide pertinent information, except that if such a location would be impractical or cause undue hardship on the owner, the city may allow such facility to be constructed in an accessible public street or sidewalk area, located so that it will not be obstructed by landscaping or parked vehicles. It shall be the responsibility of the owner to secure permission to situate any required and approved monitoring facility on any property other than that of the owner.

B. There shall be ample room in or near such monitoring facility to allow accurate sampling, data collection, and preparation of samples for analysis by the owner and the city. The facility, sampling, and measuring equipment shall be maintained at all times in a safe and proper operating condition at the expense of the owner.

C. All monitoring facilities shall be constructed and maintained in accordance with all applicable construction standards and specifications. Construction of monitoring facilities for existing dischargers shall be completed within 180 days of receipt of notice to do so from the public works director. Construction of monitoring facilities shall be completed by the owner at the owner’s own expense. (Ord. 3453 § 17, 2009).

13.33.170 Sampling and analysis requirements.

Sample types, measurements, analyses, and sample frequency required for each site shall be determined by the public works director. All measurements, tests, and analyses of characteristics of storm water shall be in accordance with procedures established by the Environmental Protection Agency contained in 40 CFR Part 136 of the federal Clean Water Act as now existing or hereafter amended. All sampling, measurements, and analysis done for the satisfaction of these requirements shall be the responsibility of the site owner and done at the owner’s expense. All samples and analysis taken shall be reported to the city. (Ord. 3453 § 18, 2009).

13.33.180 Deviations.

A. Deviations from the requirements of this chapter shall be processed as Type II permits consistent with Chapter 14.05 MVMC, and may be granted for good cause by the public works director, considering the following criteria:

1. Sufficient capacity of downstream facilities under design conditions;

2. Maintenance of the integrity of the receiving waters;

3. Possibility of adverse effects of retention/detention;

4. Utility of regional retention/detention facilities;

5. Capability of maintenance of the system;

6. Structural integrity of abutting foundations and structures;

7. Requirements of the city’s surface water management plan;

8. The health, safety and welfare of the city is not adversely affected;

9. The deviation provides equivalent environmental protection and is in the overriding public interest; and that the objectives of safety, function, environmental protection, and facility maintenance, based upon sound engineering, are fully met;

10. Special physical circumstances or conditions affecting the property such that the strict application of these provisions would deprive the applicant of all reasonable use of the site in question, and every effort to find creative ways to meet the intent of the minimum standards has been made;

11. The granting of the deviation will not be detrimental to the public health, welfare, and safety, nor injurious to other properties in the vicinity and/or downstream, and to the quality of receiving waters;

12. The deviation is the least possible exception that could be granted to comply with the intent of the minimum requirements; and

13. The deviation is fully compliant with all state and federal requirements.

B. Requests for deviations shall be filed in writing with the public works director and shall adequately detail the basis for granting a deviation. (Ord. 3700 § 11, 2016).

13.33.190 Development in critical areas.

Proposed development located wholly or partially within environmentally critical areas shall comply and be reviewed with respect to policies adopted within Chapters 15.36 and 15.40 MVMC that relate to development in critical areas and flood hazard areas. (Ord. 3453 § 20, 2009).

13.33.200 Establishment of regional facilities.

A. In the event that public benefits would accrue due to modification of the storm water plan for the subject property to better implement the recommendations of the city’s surface water plan, the public works director may recommend that the city should assume some responsibility for the further design, construction, operation, and maintenance of drainage facilities receiving runoff from the subject property. Such a decision shall be made concurrently with review and approval of the storm water plan as specified in this chapter.

B. In the event that the city decides to assume some responsibility for design, construction, operation, and maintenance of the facilities, the developer will be required to contribute, as a minimum, a pro rata share to the construction cost of the facilities. The developer may be required to supply additional information at the request of the public works director to aid in the determination by the city. Guidelines for implementing this section will be defined by the public works director. (Ord. 3453 § 21, 2009).

13.33.210 Applicability to governmental entities.

All municipal corporations and governmental entities, unless otherwise provided, shall comply with the terms of this chapter when developing and/or improving land, including, but not limited to, road building and widening, within areas of the city. (Ord. 3453 § 22, 2009).

13.33.220 Other permits and requirements.

A. It is recognized that compliance with other city, county, state and federal permits, conditions, and requirements may apply to the proposed action and that compliance with the provisions of this chapter does not constitute compliance with such other requirements.

B. When any provision of any other chapter of the MVMC conflicts with this chapter, that which provides adequate public safety and more environmental protection shall apply unless specifically provided in this chapter. (Ord. 3453 § 23, 2009).

13.33.230 Protection of public and private rights.

Implementation of any provision of this chapter shall not cause, nor be construed as, an infringement of the rights of individuals, municipalities, or corporations other than the developer seeking a permit or approval as described in MVMC 13.33.030. (Ord. 3453 § 24, 2009).

13.33.240 Enforcement, violations and penalties.

The provisions set forth in MVMC Title 19 shall apply to all violations of this chapter. Penalty and enforcement provided therein are cumulative and shall not be deemed exclusive, and the city may pursue any appropriate remedy or relief. (Ord. 3453 § 25, 2009).