City of Richland, WA Article II Wetlands

§ 26.60.020 Regulated activities in wetlands.

The following activities which occur in conjunction with a development application within a wetland and its associated buffer, or outside a wetland or buffer but affecting the wetland or buffer, shall be regulated pursuant to the standards of this chapter to achieve, at a minimum, no net loss of wetland area and ecological functions, including lost time when the wetland does not perform the function:

A. Removing, excavating, disturbing or dredging soil, sand, gravel, minerals, organic matter or materials of any kind;

B. Dumping, discharging or filling with any material;

C. Draining, flooding or disturbing the water level or water table;

D. Driving, piling or placing obstructions;

E. Constructing, reconstructing, demolishing or altering any structure or infrastructure, or if the activity results in greater impervious surface coverage;

F. Destroying or altering vegetation, including through clearing, harvesting, shading or planting vegetation that would alter the character of wetland;

G. Activities that result in significant changes in water temperature, physical or chemical characteristics of wetland water sources, including water quantity and quality as stated in Chapter 90.03 RCW and Chapter 173-201 WAC;

H. Alteration of natural drainage patterns or any activity that results in a discharge of stormwater runoff into a wetland; and

I. Any other activities affecting a wetland or wetland buffer not otherwise exempt from the provisions of this article.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.021 Exemptions and allowed uses in wetlands.

A. Wetlands. The following wetlands are exempt from the buffer provisions contained in this chapter and the normal mitigation sequencing process in RMC § 26.20.020. They may be filled if impacts are fully mitigated based on provisions in RMC § 26.60.026, Wetland alteration and mitigation. In order to verify the following conditions, a critical area report for wetlands must be submitted:

1. All isolated Category III and IV wetlands less than 1,000 square feet that:

a. Are not associated with riparian areas or buffer;

b. Are not part of a wetland mosaic;

c. Do not contain habitat identified as essential for local populations of priority species identified by the Washington Department of Fish and Wildlife or species of local importance;

d. Are not a vernal pool;

e. Are not an alkali wetland; and

f. Do not contain aspen stands.

B. Activities Allowed in Wetlands. The activities listed below are allowed in wetlands. These activities do not require submission of a sensitive area report, except where such activities result in a loss of the functions and values of a wetland or wetland buffer. These activities include:

1. Those activities and uses conducted pursuant to the Washington State Forest Practices Act and its rules and regulations, WAC 222-12-030, where state law specifically exempts local authority, except those developments requiring local approval for Class 4 – general forest practice permits (conversions) as defined in Chapter 76.09 RCW and Chapter 222-12 WAC.

2. Conservation or preservation of soil, water, vegetation, fish, shellfish, and/or other wildlife that does not entail changing the structure or functions of the existing wetland.

3. The harvesting of wild crops in a manner that is not injurious to natural reproduction of such crops, and provided the harvesting does not require tilling of soil, planting of crops, chemical applications, or alteration of the wetland by changing existing topography, water conditions, or water sources.

4. Drilling for utilities/utility corridors under a wetland, with entrance/exit portals located completely outside of the wetland buffer; 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 will be disturbed.

5. Enhancement of a wetland through the removal of nonnative invasive plant species. Removal of invasive plant species shall be restricted to hand removal unless permits from the appropriate regulatory agencies have been obtained for approved biological or chemical treatments. 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 shall occur in conjunction with removal of invasive plant species.

6. Educational and scientific research activities.

7. Normal and routine maintenance and repair of any existing public or private facilities within an existing right-of-way; provided, that the maintenance or repair does not expand the footprint or use of the facility or right-of-way.

C. Notwithstanding the exemptions provided by this chapter, any otherwise exempt activities occurring in or near wetlands shall comply with the intent of these standards and shall consider on-site alternatives that achieve no net loss of ecological wetland functions.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.022 Wetland inventory maps.

The approximate location and extent of wetlands within the city of Richland's planning area are shown on the sensitive areas maps adopted as part of this program, and provided in the city's SMP inventory, analysis and characterization report. These maps shall be used only as a general guide for the assistance of property owners and the public, as the boundaries are generalized. The actual type, extent, and boundaries of wetlands shall be determined in the field by a qualified consultant according to the procedures, definitions, and criteria established by this title. In the event of any conflict between the wetland location or designation shown on the city of Richland's maps and the criteria or standards of this title, the results of applying the criteria and standards during the field investigation shall control.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.023 Rating – Categories of wetland.

Wetlands shall be designated Category I, Category II, Category III, or Category IV according to the following criteria:

A. Categories I, II, III, and IV are set forth in the Washington State Department of Ecology's Washington State Wetlands Rating System for Eastern Washington, Publication No. 04-06-030, as may be amended in the future (hereinafter referred to as the Ecology Wetlands Rating System).

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.024 Wetland buffer areas.

A. The establishment of wetland buffer areas shall be required for all development proposals and activities adjacent to wetlands to protect the integrity, function, and value of the wetland. Buffers shall consist of an undisturbed area of vegetation established to protect the functions and values of the wetland. The standard buffer widths 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. Buffers shall be determined in conjunction with considerations of wetland type and quality, approved wetland alterations, and required mitigation measures. Buffers are not intended to be established or to function independently of the wetland they are established to protect; the establishment of a buffer shall not operate to prevent a use or activity that would otherwise be permitted in the wetland subject to mitigation.

B. Buffers shall be measured from the wetland edge as delineated using the 1987 U.S. Army Corps of Engineers Wetlands Delineation Manual and the Arid West Regional Supplement. Buffers shall be marked in the field. Required buffer widths shall be determined according to the proposed land use (Table 26.60.024(C)) and the wetland category (Table 26.60.024(D)).

C. The following table describes the types of land use:

Table 26.60.024(C) Land Use Intensity Table
Level of Impact from Proposed Change in Land Use	Types of Land Use Based on Common Zoning Designations
High	• Commercial • Urban • Industrial • Institutional • Retail sales • Residential (more than 1 unit/acre) • High intensity recreation (golf courses, ball fields, etc.) • Conversion to high intensity agriculture (dairies, nurseries, greenhouses, growing and harvesting crops requiring annual tilling and raising and maintaining animals, etc.) • Hobby farms
Moderate	• Residential (1 unit/acre or less) • Moderate intensity open space (parks with biking, jogging, etc.) • Paved driveways and gravel driveways serving 3 or more residences • Paved trails • Conversion to moderate intensity agriculture (orchards, hay fields, etc.) • Utility corridor or right-of-way shared by several utilities and including access/maintenance road
Low	• Low intensity open space (hiking, bird watching, preservation of natural resources, etc.) • Timber management (cutting of trees only) • Gravel driveways serving 2 or fewer residences • Unpaved trails • Utility corridor without a maintenance road and little or no vegetation management

D. The following buffer widths are established:

Table 26.60.024(D) Wetland Buffer Widths
Wetland Characteristics	Buffer Width by Impact of Proposed Land Use	Other Measures Recommended for Protection
Category IV Wetlands (For wetlands scoring less than 16 points for all functions)
Score for all 3 basic functions is less than 16 points	Low – 25 ft Moderate – 40 ft High – 50 ft	No recommendations at this time
Category III Wetlands (For wetlands scoring 16 – 18 points for all functions)
Moderate level of function for habitat (score for habitat 5 – 7 points)	Low – 75 ft Moderate – 110 ft High – 150 ft	No recommendations at this time
*If wetland scores 8 – 9 habitat points, see Category II buffers
Score for habitat 3 – 4 points	Low – 40 ft Moderate – 60 ft High – 80 ft	No recommendations at this time
Category II Wetlands (For wetlands that score 19 – 21 points for all functions or having the "special characteristics" identified in the rating system)
High level of function for habitat (score for habitat 8 – 9 points)	Low – 100 ft Moderate – 150 ft High – 200 ft	Maintain connections to other habitat areas
Moderate level of function for habitat (score for habitat 5 – 7 points)	Low – 75 ft Moderate – 110 ft High – 150 ft	No recommendations at this time
High level of function for water quality improvement and low for habitat (score for water quality 8 – 9 points; habitat less than 5 points)	Low – 50 ft Moderate – 75 ft High – 100 ft	No additional surface discharges of untreated runoff
Riparian forest	Buffer width to be based on score for habitat functions or water quality functions	Riparian forest wetlands need to be protected at a watershed or subbasin scale Other protection based on needs to protect habitat and/or water quality functions
Not meeting above characteristics	Low – 50 ft Moderate – 75 ft High – 100 ft	No recommendations at this time
Category I Wetlands (For wetlands that score 22 points or more for all functions or having the "special characteristics" identified in the rating system)
Wetlands of high conservation value	Low – 125 ft Moderate – 190 ft High – 250 ft	No additional surface discharges to wetland or its tributaries No septic systems within 300 ft of wetland Restore degraded parts of buffer
High level of function for habitat (score for habitat 8 – 9 points)	Low – 100 ft Moderate – 150 ft High – 200 ft	Restore degraded parts of buffer Maintain connections to other habitat areas
Moderate level of function for habitat (score for habitat 5 – 7 points)	Low – 75 ft Moderate – 110 ft High – 150 ft	No recommendations at this time
High level of function for water quality improvement (8 – 9 points) and low for habitat (less than 5 points)	Low – 50 ft Moderate – 75 ft High – 100 ft	No additional surface discharges of untreated runoff
Not meeting any of the above characteristics	Low – 50 ft Moderate – 75 ft High – 100 ft	No recommendations at this time

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.025 Buffer modifications.

A. Buffer averaging to improve wetland protection may be permitted when all of the following conditions are met:

1. The wetland has significant differences in characteristics that affect its habitat functions, such as a wetland with a forested component adjacent to a degraded emergent component or a "dual-rated" wetland with a Category I area adjacent to a lower rated area.

2. The buffer is increased adjacent to the higher functioning area of habitat or more sensitive portion of the wetland and decreased adjacent to the lower functioning or less sensitive portion as demonstrated by a critical areas report from a qualified wetland professional.

3. The total area of the buffer after averaging is equal to the area required without averaging.

4. The buffer at its narrowest point is never less than either three-quarters of the required width or 75 feet for Categories I and II, 50 feet for Category III, and 25 feet for Category IV, whichever is greater.

B. Averaging for proposed land uses may be allowed when all of the following are met:

1. There are no feasible alternatives to the site design that could be accomplished without buffer averaging.

2. 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.

3. The total buffer area after averaging is equal to the area required without averaging.

4. The buffer at its narrowest point is never less than either three-quarters of the required width or 75 feet for Categories I and II, 50 feet for Category III, and 25 feet for Category IV, whichever is greater.

C. Reduction in Buffer Width Based on Reducing the Intensity of Impacts from Proposed Land Uses.

1. The buffer widths recommended for proposed land uses with high intensity impacts to wetlands can be reduced to those recommended for moderate intensity impacts under the following conditions:

a. For wetlands that score moderate or high for habitat (five points or more for the habitat functions), the width of the buffer can be reduced if the following criteria are met:

i. A relatively undisturbed, vegetated corridor at least 100 feet wide is protected between the wetland and any other priority habitats as defined by the Washington State Department of Fish and Wildlife. "Relatively undisturbed" and "vegetated corridor" are defined in the Washington State Wetland Rating System for Eastern Washington – 2014 Update, or latest update. Priority habitats in eastern Washington include:

(A) Wetlands;

(B) Riparian zones;

(C) Cliffs;

(D) Urban natural open space.

ii. 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.

iii. Measures to minimize the impacts of different land uses on wetlands, such as the examples summarized in Table 26.60.025(D), are applied.

b. For wetlands that score fewer than five points for habitat, the buffer width can be reduced to that required for moderate land use impacts by applying measures to minimize the impacts of the proposed land uses (see examples in Table 26.60.025(D)).

D. Examples of Measures to Minimize Impacts to Wetlands from Changes in Land Uses with High Impacts.

Table 26.60.025(D) Examples of Measures to Minimize Impacts to Wetlands from Changes in Land Uses with High Impacts
Examples of Disturbance	Activities and Uses that Cause Disturbances	Examples of Measures to Minimize Impacts
Lights	• Parking lots • Warehouses • Manufacturing • Residential areas	• Direct lights away from wetland
Noise	• Manufacturing • Residential areas	• Locate activity that generates noise away from wetland
Toxic runoff*	• Parking lots • Roads • Manufacturing • Residential areas • Application of agricultural pesticides • Landscaping	• Route all new, untreated runoff away from wetland, while ensuring wetland is not dewatered • Establish covenants limiting use of pesticides within 150 ft of wetland • Apply integrated pest management
Stormwater runoff	• Parking lots • Roads • Manufacturing • Residential areas • Commercial • Landscaping	• Retrofit stormwater detention and treatment for roads and existing adjacent development • Prevent channelized flow from lawns that directly enters the buffer
Change in water regime	• Impermeable surfaces • Lawns • Tilling	• Infiltrate or treat, detain, and disperse into buffer new runoff from impervious surfaces and new lawns
Pets and human disturbance	• Residential areas	• Use privacy fencing; plant dense vegetation to delineate buffer edge and to discourage disturbance using vegetation appropriate for the ecoregion; place wetland and its buffer in a separate tract
Dust	• Tilled fields	• Use BMPs to control dust

* These examples are not necessarily adequate for minimizing toxic runoff if threatened or endangered species are present at the site.

E. The minimum buffer width stated in Table 26.60.024(D), Wetland Buffer Widths, shall be increased when the qualified consultant determines, based upon a site-specific wetland analysis, that impacts on the wetland from a proposed development can only be mitigated by a greater buffer width. The standard wetland buffer width shall be increased:

1. When the adjacent land is susceptible to severe erosion and erosion control measures will not effectively prevent adverse wetland impacts; or

2. When the standard buffer has minimal or degraded vegetative cover that cannot be improved through enhancement; or

3. When the wetland provides habitat for a species that is particularly sensitive to disturbance (listed by the federal government or the state as endangered, threatened, candidate, monitored or documented priority species or habitat for those species, or has unusual nesting or resting sites such as heron rookeries or raptor nesting trees), the width of the buffer should be increased to provide adequate protection for the species based on its particular life-history needs; or

4. When the minimum buffer for a wetland extends into an area with a slope of greater than 25 percent, the buffer shall be increased by 50 percent.

F. Low impact uses and activities (see Table 26.60.024(C)) that are consistent with the purpose and function of the wetland buffer and do not detract from its integrity may be permitted within the buffer depending on the sensitivity of the wetland. Examples of uses and activities that may be permitted in appropriate cases, based on guidance in the Wetlands and CAO Guidance for Small Cities, Eastern Washington version (dated January 2010, revised October 2012, as may be amended in the future), include pedestrian trails, viewing platforms, stormwater management facilities such as grass-lined swales, and utility easements. Uses permitted within the buffer shall be located in the outer portion of the buffer as far as possible from the wetland.

G. A variance from buffer width requirements may be granted by the city of Richland upon a demonstration by the applicant that the shoreline variance criteria are met per RMC § 26.50.060.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.026 Wetland alteration and mitigation.

A. All adverse impacts to wetland functions and values shall be mitigated. Mitigation actions by an applicant or property owner shall occur in the following priority sequence per RMC § 26.20.020(B), Ecological functions, no net loss (mitigation sequence).

B. Where impacts cannot be avoided, the applicant or property owner shall seek to implement other appropriate mitigation actions in compliance with the intent, standards, and criteria of this section. These shall include consideration of alternative site plans and building layouts and/or reduction in the density or scope of the proposal.

C. Alteration of wetlands and/or their buffers may be permitted by the city subject to the following criteria:

1. Category I Wetlands. Alterations of Category I wetlands shall be avoided.

2. Category II Wetlands.

a. Any proposed alteration and mitigation shall comply with the requirements of this section through RMC § 26.60.028, Mitigation standards, criteria, and plan requirements; and

b. No net loss of wetland function and value will occur due to the alteration.

3. Category III Wetlands.

a. The proposed mitigation complies with the requirements of this section through RMC § 26.60.028, Mitigation standards, criteria, and plan requirements; and

b. Where enhancement is proposed, replacement ratios comply with the requirements of RMC § 26.60.028(C), Wetland Replacement Ratios.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.027 Stormwater runoff.

New development within 150 feet of a wetland buffer shall contain stormwater runoff within the developed portions of the site. No stormwater runoff shall drain into the wetland. Deviations from this standard may be approved by the city; provided, that a study undertaken by a qualified consultant in accordance with the provisions of RMC § 26.60.028 indicates that the potential discharge of stormwater runoff from a development site into a wetland is adequately mitigated to protect the functions and values of the wetland. In the case of a Category III or Category IV wetland, stormwater management facilities may be located within the outer 25 percent of the required wetland buffer; provided, that a determination is made that no other location is feasible and the location of such facilities will not have an adverse impact on the functions and values of the wetland.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.028 Mitigation standards, criteria, and plan requirements.

A. Location and Timing of Mitigation.

1. Location of Compensatory Mitigation. Compensatory mitigation actions shall be conducted within the same subdrainage basin and on the site of the alteration except when all of subsections (A)(1)(a) through (d) of this section apply. In that case, mitigation may be allowed off site within the subwatershed of the impact site. When considering off-site mitigation, preference should be given to using alternative mitigation, such as a mitigation bank, an in-lieu fee program, or advanced mitigation.

a. There are no reasonable opportunities on site or within the subdrainage basin (e.g., on-site options would require elimination of high-functioning upland habitat), or opportunities on site or within the subdrainage basin do not have a high likelihood of success based on a determination of the capacity of the site to compensate for the impacts. Considerations should include: anticipated replacement ratios for wetland mitigation, buffer conditions and proposed widths, available water to maintain anticipated hydrogeomorphic classes of wetlands when restored, proposed flood storage capacity, and potential to mitigate riparian fish and wildlife impacts (such as connectivity).

b. On-site mitigation would require elimination of high-quality upland habitat.

c. Off-site mitigation has a greater likelihood of providing equal or improved wetland functions than the altered wetland.

d. Off-site locations shall be in the same subdrainage basin unless:

i. Established watershed goals for water quality, flood storage or conveyance, habitat, or other wetland functions have been established by the city and strongly justify location of mitigation at another site.

ii. The design for the compensatory mitigation project needs to be appropriate for its location (i.e., position in the landscape). Therefore, compensatory mitigation should not result in the creation, restoration, or enhancement of an atypical wetland. An atypical wetland refers to a compensation wetland (e.g., created or enhanced) that does not match the type of existing wetland that would be found in the geomorphic setting of the site (i.e., the water source(s) and hydroperiod proposed for the mitigation site are not typical for the geomorphic setting). Likewise, it should not provide exaggerated morphology or require a berm or other engineered structures to hold back water. For example, excavating a permanently inundated pond in an existing seasonally saturated or inundated wetland is one example of an enhancement project that could result in an atypical wetland. Another example would be excavating depressions in an existing wetland on a slope, which would require the construction of berms to hold the water.

2. Timing of Compensatory Mitigation. It is desirable that compensatory mitigation projects be completed prior to activities that will disturb wetlands. At the least, compensatory mitigation shall be completed immediately following disturbance and prior to use or occupancy of the action or development. Construction of mitigation projects shall be timed to reduce impacts to existing fisheries, wildlife, and flora.

3. The administrator may authorize a one-time, temporary delay in completing construction or installation of the compensatory mitigation when the applicant provides a written explanation from a qualified wetland professional as to the rationale for the delay. An appropriate rationale would include identification of the environmental conditions that could produce a high probability of failure or significant construction difficulties (e.g., project delay lapses past a fisheries window, or installing plants should be delayed until the dormant season to ensure greater survival of installed materials). The delay shall not create or perpetuate hazardous conditions or environmental damage or degradation, and the delay shall not be injurious to the health, safety, or general welfare of the public. The request for the temporary delay must include a written justification that documents the environmental constraints that preclude implementation of the compensatory mitigation plan. The justification must be verified and approved by the city.

B. Mitigation Performance Standards.

1. Adverse impacts to wetlands functions and values shall be mitigated. Mitigation actions shall be implemented in the preferred sequence identified in RMC § 26.20.020, Ecological functions, no net loss. Proposals which include less preferred and/or compensatory mitigation shall demonstrate that:

a. All feasible and reasonable measures will be taken to reduce impacts and losses to the original wetland. Describe how preferred order of wetlands mitigation was followed: (i) restoration (including reestablishment and rehabilitation); (ii) creation (establishment); (iii) enhancement in combination with restoration or creation; and (iv) preservation of high-quality, at-risk wetlands.

b. Compensatory mitigation shall be allowed only after mitigation sequencing is applied and higher priority means of mitigation are determined to be infeasible, and shall achieve equivalent or greater wetland ecological functions.

c. No overall net loss will occur in wetland functions and values.

d. The restored, created, or enhanced wetland will be as persistent and sustainable as the wetland it replaces.

C. Wetland Replacement Ratios.

1. Where wetlands alterations are permitted by the city, the applicant shall restore or create equivalent areas of wetlands in order to compensate for wetland losses. Equivalent areas shall be determined according to acreage, function, type, location, timing factors, and projected success of restoration or creation.

2. The following acreage replacement ratios shall be applied:

Table 26.60.028. Mitigation Ratios for Eastern Washington1
Category and Type of Wetland Impacts	Reestablishment or Creation	Rehabilitation Only2	Reestablishment or Creation (R/C) and Rehabilitation (RH)2	Reestablishment or Creation (R/C) and Enhancement (E)2	Enhancement Only2
All Category IV	1.5:1	3:1	1:1 R/C and 1:1 RH	1:1 R/C and 2:1 E	6:1
All Category III	2:1	4:1	1:1 R/C and 2:1 RH	1:1 R/C and 4:1 E	8:1
Category II Forested	4:1	8:1	1:1 R/C and 4:1 RH	1:1 R/C and 6:1 E	16:1
Category II Vernal Pool	2:1 Replacement must be seasonally ponded wetland	4:1 Replacement must be seasonally ponded wetland	1:1 R/C and 2:1 RH	Case-by-case	Case-by-case
All Other Category II	3:1	6:1	1:1 R/C and 4:1 RH	1:1 R/C and 8:1 E	12:1
Category I Forested	6:1	12:1	1:1 R/C and 10:1 RH	1:1 R/C and 20:1 E	24:1
Category I Based on Score for Functions	4:1	8:1	1:1 R/C and 6:1 RH	1:1 R/C and 12:1 E	16:1
Category I Wetland of High Conservation Value	Not considered possible3	6:1 Rehabilitation of a natural heritage site	R/C Not considered possible3	R/C Not considered possible3	Case-by-case
Category I Alkali	Not considered possible3	6:1 Rehabilitation of an alkali wetland	R/C Not considered possible3	R/C Not considered possible3	Case-by-case
Category I Bog	Not considered possible3	6:1 Rehabilitation of a bog	R/C Not considered possible3	R/C Not considered possible3	Case-by-case

Notes:

1. Ratios for rehabilitation and enhancement may be reduced when combined with 1:1 replacement through creation or reestablishment. See Table 1b, Wetland Mitigation in Washington State – Part 1: Agency Policies and Guidance – Version 1 (Ecology Publication No. 06-06-011a, Olympia, WA, March 2006, or as revised).

2. These ratios are based on the assumption that the rehabilitation or enhancement actions implemented represent the average degree of improvement possible for the site. Proposals to implement more effective rehabilitation or enhancement actions may result in a lower ratio, while less effective actions may result in a higher ratio. The distinction between rehabilitation and enhancement is not clear-cut. Instead, rehabilitation and enhancement actions span a continuum. Proposals that fall within the gray area between rehabilitation and enhancement will result in a ratio that lies between the ratios for rehabilitation and the ratios for enhancement.

3. Natural heritage sites, alkali wetland, and bogs are considered irreplaceable wetlands because they perform some functions that cannot be replaced through compensatory mitigation. Impacts to such wetlands would therefore result in a net loss of some functions no matter what kind of compensation is proposed.

Reference:

Washington State Department of Ecology, U.S. Army Corps of Engineers Seattle District, and U.S. Environmental Protection Agency Region 10. March 2006. Wetland Mitigation in Washington State – Part 1: Agency Policies and Guidance (Version 1). Washington State Department of Ecology Publication No. 06-06-011a, Olympia, WA.

3. Credit/Debit Method. To more fully protect functions and values, and as an alternative to the mitigation ratios found in the joint guidance "Wetland Mitigation in Washington State Parts I and II" (Ecology Publication No. 06-06-011a-b, Olympia, WA, March 2006), the 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 No. 11-06-015, August 2012, or as revised).

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.029 Wetland mitigation plan requirements.

Where it is determined by the city that compensatory wetland mitigation is required or appropriate, a mitigation plan shall be prepared consistent with the provisions below and shall also meet the minimum requirements contained in the Wetlands and CAO Guidance for Small Cities, Eastern Washington version (dated January 2010, revised October 2012, and as amended in the future). The purpose of the plan is to prescribe mitigation to compensate for impacts to the wetland functions, values, and acreage as a result of the proposed action. This plan shall consider the chemical, physical, and biological impacts on the wetland system using a recognized wetlands assessment methodology and/or best professional judgment. The mitigation plan shall be prepared in two phases, a conceptual phase and a detailed phase.

A. Conceptual Plan – Standards and Criteria. The applicant shall prepare a conceptual mitigation plan for submission to the city at a premitigation conference. The conceptual mitigation plan shall include:

1. General goals of the mitigation plan;

2. A review of literature or experience to date in restoring or creating the type of wetland proposed;

3. Location of proposed wetland compensation area;

4. General hydrologic patterns on the site following construction;

5. Nature of compensation, including wetland types (in-kind), general plant selection and justification, approximate project sequencing and schedule, and approximate size of the new wetland buffer;

6. A conceptual maintenance plan; and

7. A conceptual monitoring and contingency plan.

B. Detailed Plan – Standards and Criteria. Following acceptance of the conceptual mitigation plan by the city, the applicant will prepare a detailed mitigation plan. Each detailed plan shall contain, at a minimum, the following components, and shall be consistent with the standards in RMC § 26.60.023 through § 26.60.028:

1. A clear statement of the objectives of the mitigation. The goals of the mitigation plan should be stated in terms of the new wetland functions and values compared to the functions and values of the original wetland.

2. Qualitative and quantitative standards for success of the project, including hydrologic characteristics (water depths, water quality, hydroperiod/hydrocycle characteristics, flood storage capacity); vegetative characteristics (community types, species composition, density, and spacing); faunal characteristics, and final topographic elevations.

3. An ecological assessment of the wetland values and wetland buffers that will be lost as a result of the activities, and of the replacement wetlands and buffers, including, but not limited to, the following:

a. Acreage of project;

b. Existing functions and values;

c. Sizes of wetlands, wetland buffers, and areas to be altered;

d. Vegetative characteristics, including community type, areal coverage, species composition, and density;

e. Habitat type(s) to be enhanced, restored, or created; and

f. Dates for beginning and completion of the mitigation project, and sequence of construction activities.

4. A statement of the location, elevation, and hydrology of the new site, including the following:

a. Relationship of the project to the watershed and existing water bodies;

b. Topography of the site using the smallest readily available intervals, preferably one-foot contour intervals but two-foot is acceptable;

c. Water level data, including depth and duration of seasonally high water table;

d. Water flow patterns;

e. Grading, filling and excavation, including a description of imported soils;

f. Irrigation requirements, if any;

g. Water pollution mitigation measures during construction;

h. Areal coverage of planted areas to open water areas (if any open water is to be present); and

i. Appropriate buffers.

5. A planting plan describing what will be planted, and where and when the planting will occur, as follows:

a. Soils and substrate characteristics;

b. Specify substrate stockpiling techniques; and

c. Planting instructions, including species, stock type and size, density or spacing of plants, and water and nutrient requirements.

6. A monitoring and maintenance plan consistent with RMC § 26.60.031.

a. Specify procedures for monitoring and site maintenance, including control of invasive species; and

b. Submit monitoring reports to the city.

7. A contingency plan consistent with these regulations.

8. A detailed budget for implementation of the mitigation plan, including monitoring, maintenance, and contingency phases.

9. A guarantee, in the form of a bond or other security device in a form and amount acceptable to the city attorney, assuring that the work will be performed as planned and approved, consistent with these regulations and including monitoring, maintenance and contingency.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.030 Performance standards for wetlands mitigation planning.

A. The following performance standards shall be incorporated into mitigation plans submitted to the city of Richland:

1. Plants should be indigenous to the region (not introduced or foreign species);

2. Plants should be adaptable to a broad range of water depths;

3. Plants should be commercially available or available from local sources;

4. Plant species high in food and cover value for fish and wildlife are recommended, when possible;

5. Plants should be mostly perennial species;

6. Avoid committing significant areas of the site to species that have questionable potential for successful establishment;

7. Plant selection must be approved by a wetlands biologist/ecologist;

8. Water depth is not to exceed six and one-half feet (two meters);

9. The grade or slope that water flows through the wetland is not to exceed six percent;

10. Slopes within the wetland basin and the buffer zone should not be steeper than 3:1 (horizontal to vertical);

11. The substrate should consist of a minimum of one foot, in depth, of clean (uncontaminated with chemicals, or solid/hazardous wastes) inorganic/organic materials;

12. Planting densities and placement of plants should be determined by a qualified professional and shown on the design plans;

13. The wetland (excluding the buffer area) should not contain more than 60 percent open water as measured at the seasonal high water mark;

14. Minimum buffer widths should extend from the wetland boundary in accordance with buffer requirements in Table 26.60.024(D), Wetland Buffer Widths, for the proposed category rating of the wetland that will be created;

15. The planting plan must be approved by the community development director, or designee, or consultant acting on behalf of the city;

16. Stockpiling should be confined to upland areas, and contract specifications should limit stockpile durations to less than four weeks;

17. Planting instructions which describe proper placement, diversity, and spacing of seeds, tubers, bulbs, rhizomes, sprigs, plugs, and transplanted stock;

18. Apply controlled release fertilizer, if reasonable and prudent, at the time of planting and afterward only as plant conditions warrant (determined during the monitoring process);

19. Install an irrigation system, if necessary, for initial establishment period; and

20. Construction specifications and methods must be approved by a qualified consultant and the city.

B. On completion of construction, the wetland mitigation project must be signed off by the applicant's qualified consultant and the city. Signature will indicate that the construction has been completed as planned and all design elements have been fully and correctly implemented. If there have been changes in the implementation of the plan, a written explanation from the consulting biologist must be included.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.031 Wetland monitoring program and contingency plan.

A. A monitoring program shall be implemented to determine the success of the mitigation project and any necessary corrective actions. This chapter shall determine if the original goals and objectives are being met.

B. A contingency plan shall be established for compensation in the event that the mitigation project is inadequate or fails. A performance and maintenance bond or other acceptable security device is required to assure the applicant's compliance with the terms of the mitigation agreement. The amount of the performance and maintenance bond shall equal 125 percent of the cost of the mitigation project for a period of five years. The city may agree to reduce the bond in phases in proportion to work successfully completed over the period of the bond.

C. During monitoring, scientific procedures for establishing the success or failure of the project must be used.

D. For vegetation determinations, permanent sampling points shall be established.

E. Shrub and tree vegetation success can be defined as 80 percent survival of the original number of plants planted, with the following beginning density of vegetation planted: trees planted on 10-foot centers, with shrubs planted on three- to five-foot centers underneath and between the trees. Percent cover goals that mimic local natural healthy reference wetlands can be established for percent cover goals at year five as an alternative to percent survival goals.

F. Submit monitoring reports on the current status of the mitigation project to the city. The reports are to be prepared by a qualified consultant and reviewed by the city's consultant and should include monitoring information on wildlife, vegetation, water quality, water flow, stormwater storage and conveyance, and existing or potential degradation, and shall be produced on the following schedule:

1. At the time of construction;

2. Thirty days after planting;

3. Early in the growing season of the first year;

4. End of the growing season of the first year;

5. Twice the second year; and

6. Annually thereafter.

G. Monitor for five growing seasons. 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.

H. If necessary, correct for failures in the mitigation project.

I. Replace dead or undesirable vegetation with appropriate plantings based on the approved planting plan or RMC § 26.60.029.

J. Repair damages caused by erosion, settling, or other geomorphological processes.

K. Redesign mitigation project (if necessary) and implement the new design.

L. Correction procedures shall be approved by a qualified consultant and the city.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))

§ 26.60.032 Unauthorized alterations and enforcement.

A. When a wetland or its buffer has been altered in violation of this chapter, all ongoing development work shall stop and the critical area shall be restored. The city shall have the authority to issue a "stop-work" order to cease all ongoing development work and order restoration, rehabilitation, or replacement measures at the owner's or other responsible party's expense to compensate for violation of provisions of this chapter.

B. Requirement for Restoration Plan. All development work shall remain stopped until a restoration plan is prepared by the owner or responsible party and approved by city. Such a plan shall be prepared by a qualified professional using the currently accepted scientific principles, and shall describe how the actions proposed meet the minimum requirements described in subsection (C) of this section. The administrator shall, at the violator's expense, seek expert advice in determining the adequacy of the plan. Inadequate plans shall be returned to the applicant or violator for revision and resubmittal.

C. Minimum Performance Standards for Restoration. The following minimum performance standards shall be met for the restoration of a wetland; provided, that if the violator can demonstrate that greater functions and habitat values can be obtained, these standards may be modified:

1. The historic structure, functions, and values of the affected wetland shall be restored, including water quality and habitat functions.

2. The historic soil types and configuration shall be restored to the extent practicable.

3. The wetland and buffers shall be replanted with native vegetation that replicates the vegetation historically found on the site in species types, sizes, and densities. The historic functions and values should be replicated at the location of the alteration.

4. Information demonstrating compliance with other applicable provisions of this chapter shall be submitted to the administrator.

D. Site Investigations. The administrator is authorized to make site inspections and take such actions as necessary to enforce this chapter. The administrator shall present proper credentials and make a reasonable effort to contact any property owner before entering onto private property.

E. Penalties. See RMC § 26.60.084(B).

F. If the wetland affected cannot be restored, money from any associated penalties shall be deposited in a dedicated account for the preservation or restoration of landscape processes and functions in the watershed in which the affected wetland is located. The city may coordinate its preservation or restoration activities with others to optimize the effectiveness of the restoration action.

(Ord. 25-14 § 1.01; Ord. 12-18 § 1 (Exh. A))