Chapter 17.140
STORMWATER MANAGEMENT PERFORMANCE STANDARDS

Sections:

17.140.010    Purpose.

17.140.020    General provisions.

17.140.030    Applicability.

17.140.040    Regulated activities and allowed activities.

17.140.050    General requirements.

17.140.060    Repealed.

17.140.070    Repealed.

17.140.010 Purpose.

The provisions of these standards are intended to guide and advise all who conduct new development or redevelopment within the city of Stanwood. The provisions of these standards establish the minimum level of compliance that must be met to permit a property to be developed or redeveloped within Stanwood.

It is the purpose of these standards to:

(1) Ensure that developments are consistent with the land use, utilities and natural features elements of the Stanwood Comprehensive Plan;

(2) Minimize water quality degradation and sedimentation in rivers, streams, ponds, lakes, wetlands, and other water bodies;

(3) Minimize the impact of increased runoff, erosion, and sedimentation caused by land development and maintenance practices;

(4) Maintain and protect groundwater resources;

(5) Minimize adverse impacts of alternations on ground and surface water quantities, locations, and flow patterns;

(6) Decrease potential landslide, flood, and erosion damage to public and private property;

(7) Promote site planning and construction practices that are consistent with natural topographical, vegetational, and hydrological conditions;

(8) Maintain and protect the city of Stanwood’s stormwater management infrastructure and those downstream;

(9) Provide a means of regarding clearing and grading of private and public land while minimizing water quality impacts in order to protect public health and safety; and

(10) Provide minimum development regulations and construction procedures that will preserve, replace, or enhance, to the maximum extent practicable, existing vegetation to preserve and enhance the natural qualities of lands, wetlands and water bodies. (Ord. 1164 § 4, 2004; Ord. 1110 § 3, 2002; Ord. 929 Ch. 10(J)(1), 1995).

17.140.020 General provisions.

(1) Abrogation and Greater Restrictions. It is not intended that these standards repeal, abrogate, or impair any existing regulations, easements, covenants, or deed restrictions. However, where these standards impose greater restrictions, the provisions of these standards shall prevail.

(2) Interpretation. The provisions of these standards shall be held to be minimum requirements in their interpretation and application and shall be liberally construed to serve the purposes of this chapter. (Ord. 929 Ch. 10(J)(2), 1995).

17.140.030 Applicability.

(1) When any provision of any other section of this code conflicts with these standards, that which provides more environmental protection shall apply unless specifically provided otherwise in these standards.

(2) The city council of the city of Stanwood is authorized to adopt written procedures for the purpose of carrying out the provisions of these standards. Prior to fulfilling the requirements to these standards, the city of Stanwood shall not grant any approval or permission to conduct a regulated activity including, but not limited to, the following: building permit; grading and clearing permit; site development permit; planned residential development; right-of-way permit; shoreline substantial development permit; shoreline variance; variance; zone reclassification; subdivision; short subdivision; binding site plan; utility and other use permit; or any subsequently adopted permit or required approval not expressly exempted by these standards.

(3) Regulated activities shall be conducted only after the public works director approves a stormwater site plan that includes one or more of the following, as required by this chapter:

(a) Small parcel erosion and sediment control plan;

(b) Large parcel erosion and sediment control plan;

(c) Permanent stormwater quality control (PSQC) plan. (Ord. 1110 § 3, 2002; Ord. 929 Ch. 10(J)(3), 1995).

17.140.040 Regulated activities and allowed activities.

(1) Regulated Activities. Consistent with the minimum requirements contained in these standards, the public works director shall approve or disapprove the following activities, unless exempted in subsection (2) of this section:

(a) New Development.

(i) Land disturbing activities;

(ii) Structural development, including construction, installation or expansion of a building or other structure;

(iii) Creation of impervious surfaces;

(iv) Class IV general forest practices that are conversions from timber land to other uses;

(v) Subdivision, short subdivision, and binding site plans, as defined in RCW 58.17.020.

(b) Redevelopment. On an already developed site, the creation or addition of impervious surfaces, structural development including construction, installation, or expansion of a building or other structure; land disturbing activity; and/or replacement of impervious surface that is not part of a routine maintenance activity; and land disturbing activities associated with structural or impervious redevelopment.

(2) Exemptions.

(a) Commercial agriculture and forest practices regulated under WAC Title 222, except for Class IV general forest practices that are conversions from timber land to other uses, are exempt from the provisions of these standards.

(b) Development undertaken by the Washington State Department of Transportation in state highway rights-of-way is regulated by Chapter 173-270 WAC, the Puget Sound Highway Runoff Program.

(c) All other new development and redevelopment is subject to the minimum requirements of these standards. (Ord. 1110 § 3, 2002; Ord. 929 Ch. 10(J)(4), 1995).

17.140.050 General requirements.

(1) The 2005 Edition of the Washington State Department of Ecology’s “Stormwater Management Manual for Western Washington” is hereby adopted by reference and is hereinafter referred to as the “manual.” Local exceptions are included in Chapter 3 of the City’s Public Works Standards and are included herein by this reference.

(2) Design for stormwater systems shall be consistent with the city of Stanwood’s public works development standards.

(3) Stormwater Best Management Practices (BMPs).

(a) General. BMPs shall be used to control pollution from stormwater. BMPs shall be used to comply with these standards. BMPs may be found in the manual.

(b) Experimental BMPs. In those instances where appropriate BMPs are not in the manual, experimental BMPs should be considered. Experimental BMPs are encouraged as a means of solving problems in a manner not addressed by the manual in an effort to improve stormwater quality technology. Experimental BMPs must be approved in accordance with the approval process outlined in the manual.

(4) Illicit Discharges. Illicit discharges to stormwater drainage systems are prohibited.

(5) Design Requirements for Stormwater Facilities.

(a) Low impact development (LID) techniques for stormwater are encouraged.

(b) New stormwater ponds shall be designed with an irregular shape that utilizes the natural contours of the site and limits the use of manmade concrete walls to no more than 50 percent of the length of the perimeter pond embankment, measured at the pond bottom.

(c) Ponds that are bounded by fences shall utilize chain link fencing coated in black vinyl to reduce the aesthetic impact of the fencing.

(d) Stormwater ponds shall incorporate landscaping that provides visual screening of the pond for a minimum of 40 percent of the pond perimeter using either shrubs and evergreen trees or living fences. Spaces between planting clusters shall utilize ground cover. Trees and shrubs shall be grouped to provide a minimum of six feet for consideration of mowing equipment. Deciduous trees and shrubs shall not be provided within or around the pond area. Irrigation will be required from a homeowners’ association if non-drought-tolerant species are used in the planting design.

(i) Plants considered acceptable for living fences include barberries (Berberis darwinii and B. veruculosa), camelia (Camelia sasanqua), quince (Chenomeles), cotoneaster (Cotoneaster horizontalis, C. simonsii), forsythia (Forsythia suspensa sieboldii), winter jasmine (Jasminum nudiflorum), euonymous (Euonymous fortunei), bittersweet (Celastrus orbiculatus), and Russian vine (Polygonum).

(ii) Plants considered acceptable for shrubs include English laurel, photinia, yew, arbor-vitae, hemlock, western red cedar, hornbeam (Carpinus), hawthorn (Crataegus), cypress (Cupressocyparis) and beech (Fagus).

(e) Functional integration (such as fountains, basketball courts, tennis courts, open play areas, etc.) is strongly encouraged with stormwater facilities. (Ord. 1207 § 1, 2007; Ord. 1110 § 3, 2002; Ord. 929 Ch. 10(J)(5), 1995).

17.140.060 Approval standards – Small parcel minimum requirements.

Repealed by Ord. 1110. (Ord. 929 Ch. 10(J)(6)(a), 1995).

17.140.070 Approval standards – Large development minimum requirements.

Repealed by Ord. 1110. (Ord. 929 Ch. 10(J)(6)(b), 1995).