16.55.360 Wetlands.
(1) Delineation. Identification of wetlands and delineation of their boundaries pursuant to this Chapter shall be determined by a qualified professional in accordance with the most current approved federal wetland delineation manual and applicable regional supplements. All areas within the City’s shoreline jurisdiction meeting the wetland designation criteria in that procedure are hereby designated critical areas and are subject to the provisions of this Section, regardless of any formal identification.
(2) Rating.
(a) Wetlands shall be rated according to the Washington State Department of Ecology wetland rating system found in the Washington State Wetland Rating System for Eastern Washington (Ecology Publication #14-06-030, or as amended and approved by Ecology). This document contains definitions and methods for determining if the general criteria below are met.
(i) Category I wetlands are: 1) alkali wetlands; 2) wetlands with high conservation value that are identified by scientists of the Washington Natural Heritage Program/DNR; 3) bogs and calcareous fens; 4) mature and old-growth forested wetlands over one-quarter acre with slow-growing trees; 5) forests with stands of aspen; and 6) wetlands that perform many functions very well (scores between 22-27 points). These wetlands are those that 1) present a unique or rare wetland type; or 2) are more sensitive to disturbance than most wetlands; or 3) are relatively undisturbed and contain ecological attributes that are impossible to replace within a human lifetime; or 4) provide a high level of function.
(ii) Category II wetlands are: 1) forested wetlands in the floodplains of rivers; 2) mature and old-growth forested wetlands over one-quarter acre with fast-growing trees; 3) vernal pools; and 4) wetlands that perform functions well (scores between 19-21 points). These wetlands are difficult, though not impossible, to replace, and provide high levels of some functions. These wetlands occur more commonly than Category I wetlands, but still need a relatively high level of protection.
(iii) Category III wetlands are wetlands with a moderate level of functions (scores between 16-18 points). Wetlands scoring between 16-18 points 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.
(iv) Category IV wetlands have the lowest level of functions (scores fewer than 16 points) and are often heavily disturbed. These are wetlands should be able to be replaced, and in some cases be able to be improved. 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) Date of Wetland Rating. Wetland rating categories shall be applied as the wetland exists on the date of adoption of the rating system by the local government, as the wetland naturally changes thereafter, or as the wetland changes in accordance with permitted activities. Wetland rating categories shall not change due to illegal modifications.
(3) Mapping. The approximate location and extent of known wetlands are shown on the pertinent City critical area map. National Wetland Inventory Maps and the City critical area map regarding wetlands are to be used as a guide for the City, project applicants, and property owners, and will be periodically updated as new information becomes available. These maps are a reference and do not provide a final critical area designation. The exact location of a wetland’s boundary shall be determined through the performance of a field investigation by a qualified professional applying delineation methods described in Subsection 16.55.360(1). Wetland boundaries shall be clearly demarcated with non-degradable survey flagging labeled “WETLAND BOUNDARY” or “WETLAND DELINEATION.” Flagging shall be attached to existing vegetation or stakes at a maximum interval of 50 linear feet. Individual flags should be labeled with a wetland identifier and consecutive numbers (e.g., A-1 through A-8).
(4) Critical Area Report- Additional Requirements.
(a) Areas Addressed in Report. The following areas shall be addressed in a critical area report for wetlands:
(i) The project area of the proposed activity;
(ii) All wetlands and recommended buffers within 200 feet of the project area; and
(iii) All shoreline areas, water features, flood plains, and other critical areas, and related buffers within 200 feet of the project area.
(b) Wetland Analysis. In addition to the minimum required contents of critical area reports in Subsection 16.55.350(10), a critical area report for wetlands shall contain an analysis of the wetlands including the following site- and proposal-related information at a minimum:
(i) A written assessment and accompanying maps of the wetlands and buffers within 200 feet of the project area, including the following information at a minimum:
aa. Wetland delineation and required buffers;
bb. Existing wetland acreage;
cc. Wetland category; vegetative, faunal, and hydrologic characteristics; and
dd. Soil substrate conditions
(ii) A discussion of measures, including avoidance, minimization and mitigation, proposed to preserve existing wetlands and restore any wetlands that were degraded prior to the current proposed land use activity.
(iii) Proposed mitigation, if needed, including a written assessment and accompanying maps of the mitigation area, including the following information at a minimum:
aa. Existing wetland acreage and proposed impact area;
bb. Vegetative, faunal, and hydrologic conditions;
cc. Relationship within watershed and to existing waterbodies;
dd. Soil and substrate conditions, topographic elevations;
ee. Existing and proposed adjacent site conditions;
ff. Proposed wetland buffers;
gg. Property ownership; and
(iv) A discussion of ongoing management practices that will protect wetlands after the project site has been developed, including proposed monitoring and maintenance programs.
(c) Additional Information. When appropriate, the SMP Administrator may also require the critical area report to include an evaluation by the Department of Ecology or an independent qualified expert regarding the applicant’s analysis and the effectiveness of any proposed mitigating measures or programs, and to include any recommendations as appropriate.
(5) General Requirements.
(a) Activities in Wetland Areas. A proposed activity may only be permitted in a wetland or wetland buffer if the applicant can show that the activity, including associated mitigation measures, will not degrade the functions and values of the wetland and other critical areas.
(b) Wetland Buffers. Unless otherwise provided for in this Chapter, wetland buffers are required.
(i) Standard Buffer Widths. The standard buffer widths presume the existence of a relatively intact native vegetation community in the buffer zone adequate to protect the wetland functions and values at the time of the proposed activity. If the vegetation is inadequate then the buffer width shall be increased or the buffer should be planted to maintain the standard width.
(ii) Required standard wetland buffers, based on wetland category and land use intensity, are as follows:
Category of Wetland | Land Use with Low Impact* | Land Use with Moderate Impact* | Land Use with High Impact* |
|---|---|---|---|
IV | 25 ft. | 40 ft. | 50 ft. |
III | 75 ft. | 110 ft. | 150 ft. |
II | 100 ft. | 150 ft. | 200 ft. |
I | 125 ft. | 190 ft. | 250 ft. |
*Table 16.55.360-2. Types of proposed land use that can result in high, moderate, and low levels of impacts to adjacent wetlands.
Level of Impact from Proposed Change in Land Use | Types of Land Use |
|---|---|
High | • Commercial • Urban • Industrial •Institutional • Retail sales • Residential (more than 1 unit/acre) • Conversion to high-intensity agriculture (dairies, nurseries, greenhouses, growing and harvesting crops requiring annual tilling and raising and maintaining animals, etc.) • High-intensity recreation (golf courses, ball fields, etc.) • Hobby farms |
Moderate | • Residential (1 unit/acre or less) • Moderate-intensity open space (parks with biking, jogging, etc.) • Conversion to moderate-intensity agriculture (orchards, hay fields, etc.) • Paved trails • Building of logging roads • Utility corridor or right-of-way shared by several utilities and including access/maintenance road |
Low | • Forestry (cutting of trees only) • Low-intensity open space (hiking, bird-watching, preservation of natural resources, etc.) • Unpaved trails • Utility corridor without a maintenance road and little or no vegetation management. |
(c) Measurement of Wetland Buffers. All buffers shall be measured from the wetland boundary as surveyed in the field. The width of the wetland buffer shall be determined according to the wetland category and the proposed land use. The buffer for a wetland created, restored, or enhanced as compensation for wetland alterations shall be the same as the buffer required for the category of the created, restored, or enhanced wetland.
(d) Increased Wetland Buffer Width. The SMP Administrator may require increased buffer width in accordance with the critical area report and the most current, accurate, and complete scientific and technical information available on a case-by-case basis when a larger buffer is necessary to protect wetland functions and values based on site- specific characteristics. This determination shall be based on one or more of the following criteria:
(i) A larger buffer is needed to protect other critical areas;
(ii) The buffer or adjacent uplands has an overall slope steeper than fifteen percent (15%) or is susceptible to erosion;
(iii) And standard erosion control measures will not prevent adverse impacts to the wetland; or
(iv) The buffer area has minimal vegetative cover, although implementation of a buffer planting plan may substitute for increasing the buffer width.
In no case shall wetland buffers be increased to a width two times that of the standard required buffer.
(e) Wetland Buffer Width Averaging. The SMP Administrator may allow modification of the standard wetland buffer width in accordance with the critical area report and the most current, accurate, and complete scientific and technical information available on a case-by-case basis by averaging buffer widths. Averaging of buffer widths may only be allowed where a qualified wetlands professional demonstrates that:
(i) It will not reduce wetland functions or values;
(ii) The wetland contains variations in sensitivity due to existing physical characteristics or the character of the buffer varies in slope, soils, or vegetation, and the wetland would benefit from a wider buffer in places and would not be adversely impacted by a narrower buffer in other places;
(iii) The total area contained in the buffer area after averaging is no less than that which would be contained within the standard buffer; and
(iv) The buffer at its narrowest point is never less than either seventy-five percent (75%) of the required width or 75 feet for Category I and II, 50 feet for Category III and 25 feet for Category IV, whichever is greater.
(f) Buffers for Mitigation Shall be Consistent. All mitigation sites shall have buffers consistent with the buffer requirements of this Chapter.
(g) Buffer Conditions Shall be Maintained. Except as otherwise specified or allowed in accordance with this Chapter, wetland buffers shall be retained in their natural condition.
(h) Functionally Isolated Buffer Areas. Areas that are functionally separated from a wetland and do not provide protection to the wetland from potential adverse impacts due to preexisting roads, facilities, or vertical separation, shall be excluded from buffers otherwise required by this chapter.
(i) Allowed Buffer Uses. In addition to those uses identified in Subsection 16.55.350(8)(c), the following uses may be allowed within a wetland buffer in accordance with the review procedures of this Chapter, provided they are not prohibited by any other applicable law and they are conducted in a manner so as to minimize impacts to the buffer and adjacent wetland:
(i) Passive recreation facilities. Passive recreation facilities designed and in accordance with an approved critical area report, including:
aa. Walkways and trails, provided that those pathways are limited to minor crossings having no adverse impact on water quality. They should be generally parallel to the perimeter of the wetland, located only in the outer twenty-five percent (25%) of the wetland buffer area, and located to avoid removal of significant trees. They should be limited to pervious surfaces no more than five (5) feet in width for pedestrian use only. Raised boardwalks utilizing non-treated pilings may be acceptable.
bb. Wildlife-viewing structures.
(ii) Drilling for utilities/utility corridors under a buffer, with entrance/exit portals located completely outside of the wetland buffer boundary, provided that the drilling does not interrupt the ground water connection to the wetland or percolation of surface water down through the soil column. Specific studies by a hydrologist are necessary to determine whether the ground water connection to the wetland or percolation of surface water down through the soil column is disturbed.
(iii) Enhancement of a wetland buffer through the removal of non-native invasive plant species. Removal of invasive plant species shall be restricted to hand removal. All removed plant material shall be taken away from the site and appropriately disposed of. Plants that appear on the Washington State Noxious Weed Control Board list of noxious weeds must be handled and disposed of according to a noxious weed control plan appropriate to that species. Revegetation with appropriate native species at natural densities is allowed in conjunction with removal of invasive plant species.
(iv) Stormwater management facilities. Stormwater management facilities are limited to stormwater dispersion outfalls and bioswales. They may be allowed within the outer twenty-five percent (25%) of the buffer of Category III or IV wetlands only, provided that:
aa. No other location is feasible; and
bb. The location of such facilities will not degrade the functions or values of the wetland; and
cc. Stormwater management facilities are not allowed in buffers of Category I or II wetlands.
(v) Non-Conforming Uses. Repair and maintenance of non-conforming uses or structures, where legally established within the buffer, provided they do not increase the degree of nonconformity.
(j) Subdivisions. The subdivision and short subdivision of land in wetlands and associated buffers is subject to the following:
(i) Land that is located wholly within a wetland or its buffer may not be subdivided.
(ii) Land that is located partially within a wetland or its buffer may be divided provided that an accessible and contiguous portion of each new lot:
aa. Is located outside of the wetland and its buffer; and
bb. Meets the minimum lot size requirements of the City zoning code (Title 17).
(iii) Access roads and utilities serving a proposed subdivision or other property may be permitted within the wetland and associated buffers only if the SMP Administrator determines that no other feasible alternative exists and these facilities are otherwise established consistent with the provisions of this Chapter.
(k) Signs and Fencing of Wetlands.
(i) Temporary Markers. The outer perimeter of the wetland or buffer and the limits of those areas to be disturbed pursuant to an approved development permit shall be marked in the field in such a way as to ensure that no unauthorized intrusion will occur prior to the commencement of permitted activities. This temporary marking shall be maintained throughout construction, and shall not be removed until permanent signs, if required, are in place.
(ii) Permanent Signs. As a condition of any development permit, the SMP Administrator may require the applicant to install permanent signs along the boundary of a wetland and/or buffer. If required, permanent signs shall be made of a metal face and attached to a metal post, or another material of equal durability. Signs must be posted at an interval of one per lot or every 50 linear feet, whichever yields the greater amount of signs, and must be maintained by the property owner in perpetuity. The sign shall be worded as follows or with alternative language approved by the SMP Administrator:
“Protected Wetland Area Do Not Disturb
Contact City of Pullman Regarding Uses and Restrictions”
(iii) Fencing.
aa. As a condition of any development permit, the SMP Administrator may require the applicant to install a permanent fence at the edge of the wetland buffer, when fencing will prevent future impacts to the wetland.
bb. The applicant shall be required to install a permanent fence around the wetland or buffer when domestic grazing animals are present or may be introduced on site.
cc. Fencing installed as part of a proposed activity or as required in this Paragraph shall be designed so as to not interfere with species migration, including fish runs, and shall be constructed in a manner that minimizes impacts to the wetland and associated habitat.
dd. At no time shall treated wood posts (e.g., creosote) be allowed in wetland areas or in adjacent uplands to prevent chemicals from migrating into the wetland.
(6) Compensatory Mitigation.
(a) Projects that propose compensation for wetland acreage and/or functions are subject to State and Federal regulations. Compensatory mitigation for alterations to wetlands shall provide for no net loss of wetland functions and values. Compensatory mitigation for alterations to wetlands shall be used only for impacts that cannot be avoided or minimized and shall achieve equivalent or greater biologic functions. Compensatory mitigation plans shall be consistent with the mitigation plan requirements of 16.55.350(13); Wetland Mitigation in Washington State – Part 2: Developing Mitigation Plans--Version 1, (Ecology Publication #06-06-011b, Olympia, WA, March 2006 or as amended); and Selecting Wetland Mitigation Sites Using a Watershed Approach (Eastern Washington) (Publication #10-06-07, November 2010).
(b) Mitigation for Lost Functions and Values. Mitigation actions shall address functions affected by the alteration to achieve functional equivalency or improvement, and shall provide similar wetland functions as those lost except when:
(i) The lost wetland provides minimal functions as determined by a site-specific function assessment and the proposed mitigation action(s) will provide equal or greater functions or will provide functions shown to be limiting within a watershed through a formal watershed assessment protocol; or
(ii) Out-of-kind replacement will best meet formally identified regional goals, such as replacement of historically diminished wetland types.
(c) Preference of Mitigation Actions. Mitigation actions that require compensation by replacing, enhancing, or substitution, shall occur in the following order of preference:
(i) Restoring wetlands on upland sites that were formerly wetlands;
(ii) Creating wetlands on disturbed upland sites such as those with vegetative cover consisting primarily of exotic introduced species;
(iii) Enhancing significantly degraded wetlands;
(iv) Preserving high-quality wetlands that are under imminent threat.
(d) Location of Mitigation.
(i) Mitigation actions shall be conducted on the same site as the alteration except when the following apply:
aa. There are no reasonable on-site opportunities or on-site opportunities do not have a high likelihood of success due to development pressures, adjacent land uses, or on-site buffers or connectivity are inadequate;
bb. Off-site mitigation has a greater likelihood of providing equal or improved wetland functions than the impacted wetland.
(ii) If the SMP Administrator authorizes off-site mitigation, the location of this mitigation shall be in the same drainage basin and the same Water Resource Inventory Area (WRIA) as the site of the alteration unless:
aa. Established regional or watershed goals for water quality, flood or conveyance, habitat, or other wetland functions have been established and strongly justify location of mitigation at another site; or
bb. Credits from a state certified wetland mitigation bank are used as mitigation and the use of these credits justifies location of mitigation at another site.
(iii) Off-site locations for mitigation should be within the City limits if feasible opportunities for appropriate mitigation are available.
(e) Mitigation Ratios.
(i) Wetland mitigation ratios shall be consistent with Table 16.55.360-3.
Category and Type of Wetland | Creation or Re-establishment | Rehabilitation | Enhancement |
|---|---|---|---|
Category I: Bog, Wetlands with High Conservation Value | Not considered possible | Case by case | Case by case |
Category I: 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 |
(ii) To more fully protect functions and values, and as an alternative to the mitigation ratios in Table 16.55.360-3, the SMP Administrator may allow mitigation based on the “credit/debit” method developed by the Department of Ecology in “Calculating Credits and Debits for Compensatory Mitigation in Wetlands of Eastern Washington: Final Report” (Ecology Publication #11-06-015, August 2012, or as amended).
(iii) Impacts to wetland buffers shall be mitigated at a 1:1 ratio. Compensatory buffer mitigation shall replace those buffer functions lost from development.
(f) Wetland Mitigation Banks.
(i) Credits from a wetland mitigation bank may be approved for uses as compensation for unavoidable impacts to wetlands when:
aa. The bank is certified through applicable provisions administered by the Department of Ecology and the Army Corps of Engineers;
bb. The SMP Administrator determines that the wetland mitigation bank provides appropriate compensation for the authorized impacts; and
cc. The proposed use of credits is consistent with the terms and conditions of the bank’s certification.
(ii) Replacement ratios for projects using bank credits shall be consistent with replacement ratios specified in the bank’s certification.
(iii) Credits from a certified wetland mitigation bank may be used to compensate for impacts located within the service area specified in the bank’s certification. In some cases, bank service areas may include portions of more than one WRIA for specific wetland functions.
(g) Advance Mitigation. Mitigation for projects with pre-identified impacts to wetlands may be constructed in advance of the impacts if the mitigation is implemented according to federal rules, State policy on advance mitigation, and State water quality regulations.
(h) Monitoring. Mitigation monitoring shall be required for a period necessary to establish that performance standards have been met, but not for a period less than five years. If a scrub-shrub or forested vegetation community is proposed, monitoring may be required for ten years or more. The project mitigation plan shall include monitoring elements that ensure certainty of success for the project’s natural resource values and functions. If the mitigation goals are not obtained within the initial five-year period, the applicant remains responsible for restoration of the natural resource values and functions until the mitigation goals agreed to in the mitigation plan are achieved.
(i) Wetland Preservation as Mitigation. Preservation of high-quality, at-risk wetlands as compensation is generally acceptable when done in combination with restoration, creation, or enhancement, provided that a minimum of 1:1 acreage replacement is provided by re-establishment or creation. Ratios for preservation in combination with other forms of mitigation generally range from 10:1 to 20:1, as determined on a case-by-case basis, depending on the quality of the wetlands being altered and the quality of the wetlands being preserved.
Preservation of high-quality, at-risk wetlands and habitat may be considered as the sole means of compensation for wetland impacts when the following criteria are met:
(i) The area proposed for preservation is of high quality. The following features may be indicative of high-quality sites:
aa. Category I or II wetland rating (using the wetland rating system for eastern Washington).
bb. Rare wetland type (for example, bogs, mature forested wetlands, estuarine wetlands).
cc. The presence of habitat for priority or locally important wildlife species.
dd. Priority sites in an adopted watershed plan.
(ii) Wetland impacts will not have a significant adverse impact on habitat for listed fish, or other ESA-listed species.
(iii) There is no net loss of habitat functions within the watershed or basin.
(iv) Mitigation ratios for preservation as the sole means of mitigation shall generally start at 20:1. Specific ratios should depend upon the significance of the preservation project and the quality of the wetland resources lost.
(v) Permanent preservation of the wetland and buffer will be provided through a conservation easement or tract held by a land trust.
(vi) The impact area is small (generally less than half an acre) and/or impacts are occurring to a low-functioning system (Category III or IV wetland).
All preservation sites shall include buffer areas adequate to protect the habitat and its functions from encroachment and degradation. (Ord. 16-3 §37, 2016).