11.50.130 Wetlands | Selah Municipal Code

11.50.130 Wetlands.

(a) Classification. The city of Selah adopts wetland determinations as set forth in RCW 36.70A.030(20) or as may be amended and classification shall be in accordance with the Washington State Wetlands Rating System for Eastern Washington, Publication No. 14-06-030, or as updated or amended:

(1) Category I. Category I wetlands are those that represent a unique or rare wetland type; are more sensitive to disturbance than most other wetlands; are relatively undisturbed and contain ecological attributes that are impossible to replace within a human lifetime; or those that provide a very high level of functions. The city of Selah does not wish to risk any degradation to these wetlands. Generally, these wetlands are not common and make up a small percentage of the wetlands in Eastern Washington. The following types of wetlands are Category I:

(A) Alkali wetlands;

(B) Wetlands of high conservation value that are identified by scientists of the Washington Natural Heritage Program/DNR;

(D) Mature and old-growth forested wetlands over one-quarter acre with slow growing trees;

(E) Forests with stands of aspen; and

(F) Wetlands that perform many functions very well (scores between twenty-two and twenty-seven).

(2) Category II. Category II wetlands are those wetlands that are difficult, though not impossible, to replace. They provide high levels of some functions. These wetlands occur more commonly than Category I wetlands, but still need a relatively high level of protection.

The following wetlands are Category II:

(A) Forested wetlands in the floodplains of rivers;

(B) Mature and old-growth forested wetlands over one-quarter acre with fast growing trees;

(D) Wetlands that perform functions well. These wetlands score between nineteen and twenty-one points on the wetlands rating system.

(3) Category III. Category III wetlands are wetlands with a moderate level of functions and can be adequately replaced with a well-planned mitigation project. Category III wetlands generally have been disturbed in some ways, and are often less diverse or more isolated from other natural resources in the landscape than Category II wetlands.

(4) Category IV. Category IV wetlands have the lowest levels of functions and are often heavily disturbed. These are wetlands that we should be able to replace, and in some cases, improve. However, experience has shown that replacement cannot be guaranteed in any specific case. These wetlands may provide some important functions, and also need to be protected.

(b) Designation. To date there has been no wetlands fields inventory done specifically for the city of Selah vicinity. To remedy this, the city should pursue an accurate accounting of all wetlands in the city's urban growth area based on the manual and methodology used to identify wetlands in the field, in accordance with the approved federal wetland delineation manual and applicable regional supplements. However, until funding is obtained to conduct a comprehensive inventory of wetlands, the National Wetlands Inventory (NWI) maps shall be used as a base designation. The NWI maps, along with other supportive documentation, shall be used to review development proposals, but because the National Wetlands Inventory was done at such a broad scale, local verification according to the classification criteria shall be part of the standard process for identifying and designating wetlands.

(c) Performance Standards. In addition to the general provisions of this section and the requirements of the underlying zoning district, the following minimum standards shall apply to the development activities within and adjacent to wetland areas:

(1) The following buffer zones are required adjacent to and outside of all regulated wetlands according to the following schedule. The following buffer widths are based on the category of wetland and the habitat score as determined by a qualified wetland professional using the Washington State Wetlands Rating System for Eastern Washington, Publication No. 14-06-030, or as updated or amended. The adjacent land use intensity is assumed to be high.

(A) For wetlands that score five points or more for habitat function, the buffers in Table 130.1 can be used if both of the following criteria are met:

(i) A relatively undisturbed, vegetated corridor of at least one hundred feet wide is protected between the wetland and any other priority habitats on the subject property as defined by the Washington State Department of Fish and Wildlife. The latest definitions of priority habitats and their locations are available on the WDFW website at: http://wdfw.wa.gov/hab/phshabs.htm

The corridor must be protected for the entire distance between the wetland and the priority habitat by some type of legal protection such as a conservation easement.

Presence or absence of a nearby habitat must be confirmed by a qualified biologist. If no option for providing a corridor is available, Table 130.1 may be used with the required measures in Table 130.2 alone.

(ii) The measures in Table 130.2 are implemented, where applicable, to minimize the impacts of adjacent land uses.

(B) For wetlands that score three to four habitat points, only the measures in Table 130.2 are required for the use of Table 130.1.

(C) If an applicant chooses not to apply the mitigation measures in Table 130.2 and is unable to provide a protected corridor where available, then Table 130.3 must be used.

(D) The buffer widths in Tables 130.1 and 130.3 assume that the buffer is vegetated with a native plant community appropriate for the ecoregion. If the existing buffer is unvegetated, sparsely vegetated, or vegetated with invasive species that do not perform needed functions, the buffer should either be planted to create the appropriate plant community or the buffer should be widened to ensure that adequate functions of the buffer are provided.

Table 130.1 Wetland Buffer Requirements if Table 130.2 Is Implemented and Corridor Provided
	Buffer Width (in feet) Based on Habitat Score
Wetland Category	3 – 5	6 – 7	8 – 9
Category I:
Based on Total Score and Forested	100	150	200
Category I:
Bogs and Wetlands of High Conservation Value	250 (buffer width not based on habitat scores)
Category I:
Alkali	200 (buffer width not based on habitat scores)
Category II:
Based on Total Score and Forested	100	150	200
Category II:
Vernal Pool	200 (buffer width not based on habitat scores)
Category III (all)	80	150	200
Category IV (all)	50

Table 130.2 Required Measures to Minimize Impacts to Wetlands
Disturbance	Required Measures to Minimize Impacts
Lights	• Direct lights away from wetland
Noise	• Locate activity that generates noise away from wetland • If warranted, enhance existing buffer with native vegetation plantings adjacent to noise source • For activities that generate relatively continuous, potentially disruptive noise, such as certain heavy industry or mining, establish an additional 10' heavily vegetated buffer strip immediately adjacent to the outer wetland buffer
Toxic Runoff	• Route all new, untreated runoff away from wetland while ensuring wetland is not dewatered • Establish covenants limiting use of pesticides within 150' of wetland • Apply integrated pest management
Storm Water Runoff	• Retrofit storm water detention and treatment for roads and existing adjacent development • Prevent channelized flow from lawns that directly enters the buffer • Use low-intensity development techniques (for more information refer to the drainage ordinance and manual)
Changes in Water Regime	• Infiltrate or treat, detain, and disperse into buffer new runoff from impervious surfaces and new lawns
Pets and Human Disturbance	• Use privacy fencing OR plant dense native vegetation to delineate buffer edge and to discourage disturbance using vegetation appropriate for the ecoregion • Place wetland and its buffer in a separate tract or protect with a conservation easement
Dust	• Use best management practices to control dust

Table 130.3 Wetland Buffer Requirements if Table 130.2 is Not Implemented or Corridor Not Provided
	Buffer Width (in feet) Based on Habitat Score
Wetland Category	3 – 5	6 – 7	8 – 9
Category I:
Based on Total Score and Forested	75	110	150
Category I:
Bogs and Wetlands of High Conservation Value	190 (buffer width not based on habitat scores)
Category I:
Alkali	150 (buffer width not based on habitat scores)
Category II:
Based on Total Score and Forested	75	110	150
Category II:
Vernal Pool	150 (buffer width not based on habitat scores)
Category III (all)	60	110	150
Category IV (all)	40

(E) Buffer averaging to allow reasonable use of the parcel may be permitted when all of the following are met:

(i) There are no feasible alternatives to the site design that could be accomplished without buffer averaging; and

(ii) The averaged buffer will not result in degradation of the wetland's functions and values as demonstrated by a critical areas report from a qualified wetland professional; and

(iii) The total buffer area after averaging is equal to the area required without averaging; and

(iv) The buffer at its narrowest point is never less than either seventy-five percent of the required buffer width or seventy-five feet for Category I and II, or fifty feet for Category III, and twenty-five feet for Category IV, whichever is greater.

(2) Greater buffer widths or revegetation of an inadequate plant community may be required where necessary to ensure development does not result in adverse impacts to wetlands.

(A) Impacts allowed under this provision to these wetlands will be fully mitigated as required in the mitigation section.

(B) Mitigation consistent with the mitigation ratios set forth in Table A-19, Wetland Guidance for CAO Updates, Eastern Washington Version: June 2016, Publication No. 16-06-002, or as may be updated or amended, may be required.

(3) Wetland buffer zones shall be retained in their natural condition. Where buffer disturbances are unavoidable during adjacent construction, revegetation with native plant materials will be required.

(4) Wetland alteration proposals shall be approved only if no alternative is available. When no alternative exists, wetland replacement shall be used to mitigate impacts and shall be based on the functions and values of the particular wetland being impacted. Simplified ratios for wetlands replacement projects shall be as follows:

	Type of Mitigation*
Category and Type of Wetland	Creation or Reestablishment	Rehabilitation	Enhancement
Category I: Bog, Natural Heritage Site	Not considered possible	Case by case	Case by case
Category I: Mature Forested	6:1	12:1	24:1
Category I: Based on Functions	4:1	8:1	16:1
Category II	3:1	6:1	12:1
Category III	2:1	4:1	8:1
Category IV	1.5:1	3:1	6:1

*Mitigation types defined in Section 11.50.030, Definitions – "Mitigation."

Wetland enhancement ratios shall not be less than one and one-half to one for replacement.

(5) The following activities are allowed to occur in wetlands and wetland buffer zones subject to conditioning with appropriate best management practices to minimize impacts on the functions and values of wetlands:

(A) Outdoor passive recreational activities;

(B) Existing and ongoing agricultural activities (provided no additional area is added beyond demonstrated historic levels within the past five years). Agricultural activities in this section do not include the processing of agricultural products or other industrial aspects of agriculture.

(6) Maintenance of existing facilities, structures, ditches, roads and utility systems. All projects shall comply with the applicable federal, state and local regulations regarding the species.

(7) As determined through the site-specific study, mitigation measures shall be implemented that maintain the functions and values found in the particular wetland.

(8) As determined through the site-specific study, appropriate mitigation, management and monitoring plan(s) may be developed and implemented, with any necessary security to ensure compliance with such plan(s) being provided as described in Section 11.50.080(c)(4)(J).

(9) A use or structure established prior to April 22, 2014, which does not conform to standards set forth herein is allowed to continue and be reasonably maintained; provided, that such activity or structure shall not be expanded or enlarged in any manner that increases the extent of its nonconformity.

(10) Compensatory mitigation plans and reports to address wetland or wetland buffer impacts should be prepared in accordance with Wetland Mitigation in Washington State – Part 2: Developing Mitigation Plans (Version 1) (Ecology Publication No. 06-06-011b), or as amended. (Ord. 2124, § 2 (Att.), 2021.)