Critical Areas Study · This report also discusses the methods that have been and will be used to best avoid, minimize, and mitigate impacts to critical areas resulting from the project

Critical Areas Study Twin City-Stanwood 115kV Transmission Rebuild Project

Public Utilities District No. 1 of Snohomish County Snohomish County, Washington

February 7, 2020


February 7, 2020 | i

Contents

1 Introduction........................................................................................................................................ 1

1.1 Project Purpose ......................................................................................................................... 1

1.2 Project Setting ........................................................................................................................... 1

1.3 Project Description .................................................................................................................... 1

2 Applicable Regulations ..................................................................................................................... 0

2.1 Wetlands ................................................................................................................................... 0

2.2 Habitat Conservation Areas ...................................................................................................... 1

2.3 Geologically Hazardous Areas .................................................................................................. 2

2.4 Aquifer Recharge Areas ............................................................................................................ 2

2.5 Special Flood Hazard Areas ..................................................................................................... 3

3 Study Methods ................................................................................................................................... 3

3.1 Study Area ................................................................................................................................. 3

3.2 Review of Existing Information .................................................................................................. 3

3.3 Field Investigation ..................................................................................................................... 4 3.3.1 Wetlands ...................................................................................................................... 4 3.3.2 Fish and Wildlife Habitat Conservation Areas .............................................................. 7 3.3.3 Ditches ......................................................................................................................... 9

4 Results ................................................................................................................................................ 9

4.1 Wetlands ................................................................................................................................... 9

4.2 Fish and Wildlife Habitat Conservation Areas ......................................................................... 12 4.2.1 Waterbodies ............................................................................................................... 12 4.2.2 Federal and State Threatened and Endangered Species .......................................... 13 4.2.3 State Designated Priority Habitats and Species ........................................................ 15 4.2.4 State Listed Sensitive Species ................................................................................... 15

4.3 Geologically Hazardous Areas ................................................................................................ 16

4.4 Aquifer Recharge Areas .......................................................................................................... 17

4.5 Special Flood Hazard Areas ................................................................................................... 17

5 Impacts ............................................................................................................................................. 17

5.1 Wetlands and Wetland Buffer Impacts .................................................................................... 17

5.2 Fish and Wildlife Habitat Conservation Areas ......................................................................... 18 5.2.1 Waterbodies and Buffers ............................................................................................ 18 5.2.2 Threatened, Endangered and Sensitive Species ....................................................... 18

5.3 Special Flood Hazard Areas ................................................................................................... 18

5.4 Critical Aquifer Recharge Areas .............................................................................................. 18

5.5 Geologically Hazardous Areas ................................................................................................ 18

6 Mitigation .......................................................................................................................................... 19

7 References ....................................................................................................................................... 20


ii | February 7, 2020

Tables

Table 1. Standard Wetland Buffer Widths in Snohomish County ................................................................. 0 Table 2. Wetland Rating System .................................................................................................................. 6 Table 3. Summary of the Water Typing System and Standard Riparian Buffer Widths for

Snohomish County Streams ....................................................................................................... 8 Table 4. Summary of Wetlands Delineated in Study Area ............................................................................ 9 Table 5. Wetland 13/3 Summary ................................................................................................................ 10 Table 6. Wetland 13/4 Summary ................................................................................................................ 11 Table 7. Summary of Streams in the Project Study Area (from North to South) ........................................ 12 Table 8. Stream information summary—Irvine Slough ............................................................................... 12 Table 9. Stream information summary—Jorgenson Slough ....................................................................... 13 Table 10. Summary of Ditches in the Project Study Area ........................................................................... 13 Table 11. Federally listed Species in the Study Area ................................................................................. 14 Table 12. Snohomish County Wetland and Buffer Impacts ........................................................................ 18

Figures

Figure 1. Project Vicinity ............................................................................................................................... 3 Figure 2. Project Map Book ........................................................................................................................... 4

Appendices

Appendix A. Wetlands and Fish and Wildlife Conservation Areas Report


February 7, 2020 | 1

1 Introduction This report has been prepared to address documentation needs specified within the Snohomish County (County) Critical Areas Ordinance (Snohomish County Code [SCC] 30.62). It addresses critical areas as defined in the SCC that occur in the Public Utility District No. 1 of Snohomish County (District) Twin City-Stanwood 115 kV Transmission Rebuild Project (project) alignment that may potentially be affected by project activities. This report also discusses the methods that have been and will be used to best avoid, minimize, and mitigate impacts to critical areas resulting from the project. Contents of the report have been prepared using guidelines presented in SCC 30.62A and 30.62B. In addition, this report discusses Special Flood Hazard Areas pursuant to SCC 30.65.

1.1 Project Purpose One of the existing electric transmission lines bringing power to customers in the northwest County area and Camano Island is reaching its end-of-life. Many of the poles and associated equipment are aging and in need of replacement. The District plans to rebuild the aging power line between the new Twin City substation site (unincorporated Snohomish County) and the existing North Stanwood Substation (at 1st Street/84th Avenue NW in the city of Stanwood) with new iron poles and higher-capacity wire. By doing so, customers in the area will see improved reliability and additional capacity.

1.2 Project Setting The project alignment is approximately 1.25 mile long. Approximately 0.25 mile is within the city of Stanwood and 1.0 mile is within unincorporated Snohomish County. The project begins at the Twin City substation in unincorporated Snohomish County. It then travels northwest primarily paralleling west of the BNSF railroad and ends at North Stanwood Substation in the city of Stanwood.

The project is located within Washington Water Resource Inventory Areas (WRIA) #5 (Stillaguamish River) and occurs within the within Sections 19 and 30 in Township 32N, Range 4E.

The majority of the project alignment currently consists of agriculture, rural residential, and rail land uses. The alignment is generally flat. Surrounding land uses consist of residential, commercial, and agricultural areas.

1.3 Project Description The proposed project consists of 22 new iron/steel poles (approximately 80 feet tall) replacing 14 existing poles, the majority of which are wooden poles. Four of these poles are located in the city of Stanwood (Pole 13/8 to Pole 13/4) and ten of these existing poles are located within Snohomish County (Pole 13/3 to Pole 12/3). Existing overhead distribution lines will be transferred from the existing poles to the new poles. The new line will be visually similar to the existing line with new poles and wire. The proposed project site plan is shown on Figure 2.


2 | February 7, 2020

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Figure 1. Project Vicinity

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2 Applicable Regulations This section provides an overview of regulations that may apply to the project. The County regulates critical areas and their applicable buffers under Chapter 30.62 of the SCC. Critical areas regulated by the County include the following: wetlands, critical aquifer recharge areas, geologically hazardous areas, and fish and wildlife habitat conservation areas (FWHCAs). Special flood hazards are regulated under Chapter 30.65 of the SCC.

Critical area classifications, required buffer widths, and mitigation requirements as specified in the code will be discussed in further detail in the applicable sections below. Regulations other than those specified in Chapters 30.62 and 30.65 of the SCC are not discussed in this document, but are addressed in the State Environmental Policy Act Environmental Checklist prepared separately for the project.

2.1 Wetlands Snohomish County regulates wetlands and their buffers under SCC 30.62A. Wetlands are defined as areas “that are inundated or saturated by surface water or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions.” (SCC 30.91W.060).

SCC requires that wetlands be rated using the Washington State Wetland Rating System for Western Washington: 2014 Update, Washington State Department of Ecology (Ecology) Publication #14-06-029 (Hruby 2014). A detailed analysis of wetland functions is not included in this report; however, a brief description of wetland functions based on the wetland rating method is included in the general description of the wetlands identified within the study area.

The County (SCC 30.62A.320) determines standard wetland buffers according to the assigned wetland category in the Ecology wetland rating system, plus land use intensity (Error! Reference source not found.).

Table 1. Standard Wetland Buffer Widths in Snohomish County

Wetland Category

Description Standard Buffer

Width Requirements (feet)**

Wetlands containing salmonids (minimum) 150

Category I

Wetlands listed by the Washington Natural Heritage Program as having High Conservation Value

190

Bogs 190

Estuarine wetlands (greater than or equal to one acre) and coastal lagoons (greater than or equal to 1/10 acre)

150

High level habitat function (habitat function score is 8–9)

225



Wetland Category

Description Standard Buffer

Width Requirements (feet)**

Moderate level habitat function (habitat function score is 5–7)

110

Total score 23 or above but not meeting above criteria

75

Category II

Estuarine wetlands (less than 1 acre) 110

High level of function for habitat (habitat function score is 8–-9)

225

Moderate to high level of function for habitat (habitat function score is 5–7)

110

High level of function for water quality improvement and low for habitat (water quality function score is 8–-9 and habitat function score is less than 5)

75

Total score 20–-22 but not meeting above criteria

75

Category III

Moderate level habitat function (habitat function score is 5–7)

110

Total score of 16–19 but not meeting above criteria

60

Category IV Low level function score (less than 16) 40

**Standard buffers represent moderate level land use intensity and include uses that are not defined as high or low intensity. High and low intensity land use wetland buffers and their requirements are defined in SCC 30.62A.340(4)(c).

2.2 Habitat Conservation Areas FWHCAs designated by Snohomish County include streams, lakes, naturally occurring ponds under 20 acres, marine waters, primary association areas of critical species, and buffers. Critical species are those species that are either listed by the state or federal government as endangered or threatened, species of local importance, or the following state listed sensitive species:

Larch mountain salamander (Plethodon larselli) Common loon (Gavia immer) Peregrine falcon (Galco peregrinus) Olympic mudminnow (Novumbre hubbsi) Pygmy whitefish (Prosopium coulteri) Gray whale (Eschrichtius robustus) Bald eagle (Haliaeetus leucocephalus) Margined sculpin (Cottus marginatus).

No other species of local importance have been designated.



2.3 Geologically Hazardous Areas Snohomish County defines geologically hazardous areas as areas that because of their susceptibility to erosion, sliding, earthquake, or other geologic events, may not be suited to the siting of commercial, residential, or industrial development consistent with public health or safety concerns (SCC 30.91G.020). Types of geologically hazardous areas regulated by the County include: erosion, landslide, seismic, mine, volcanic hazards and tsunami hazard areas. The following are considered known or suspected geologically hazardous areas.

Erosion hazards are defined in SCC 30.91E.160 E as:

o Areas containing soils which are at high risk from water erosion according to the mapped description units of the United States Department of Agriculture Natural Resources Conservation Service (NRCS), formerly the Soil Conservation Service, National Soil Classification System

o Channel migration zones

o The shorelines of water bodies subject to wind and wave erosion.

Landslide hazards (SCC 30.91L.040) means areas potentially subject to mass earth movement based on a combination of geologic, topographic, and hydrologic factors, with a vertical height of 10 feet or more. These include the following:

o Areas of historic landslides as evidenced by landslide deposits, avalanche tracks, and areas susceptible to basal undercutting by streams, rivers or waves;

o Areas with slopes steeper than 33 percent which intersect geologic contacts with a relatively permeable sediment overlying a relatively impermeable sediment or bedrock, and which contain springs or ground water seeps;

o Areas located in a canyon or an active alluvial fan, susceptible to inundation by debris flows or catastrophic flooding.

Seismic hazard areas that have been determined to have known or inferred faults, ground rupture potential, liquefaction potential, or seismically induced slope instability (SCC 31S.121).

Volcanic hazard areas are subject to pyroclastic flows, lava flows, debris flows, mud flows, or related flooding resulting from volcanic activity originating on Glacier Peak, as indicated on maps produced by the USGS (SCC 30.91V.030).

Mine hazard areas are areas underlain by or affected by underground mine workings such as tunnels, air shafts and those areas adjacent to steep slopes produced by open pit mining or quarrying, but excluding any areas where the mine workings have been properly stabilized and closed and made safe consistent with all applicable federal, state and local laws (SCC 30.91M.090).

2.4 Aquifer Recharge Areas The County has established three classifications of critical aquifer recharge areas (SCC 30.62C.220):



Sole source aquifers designated by the U.S. Environmental Protection Agency in accordance with the Safe Drinking Water Act of 1974 (Public Law 93-523)

Areas within the 10-year travel zone of Group A wellhead protection areas, determined in accordance with delineation methodologies specified by the Washington Department of Health under authority of Chapter 246-290 WAC

Areas of high, medium, and low sensitivity to groundwater contamination, based on depth to groundwater and in accordance with The Ground-Water System and Ground-Water Quality in Western Snohomish County, Washington

2.5 Special Flood Hazard Areas The County defines special flood hazard areas as those lands in the floodplain subject to a 1 percent or greater chance of flooding in any given year as determined by the Flood Insurance Rate Maps for Snohomish County, revised September 16, 2005 (SCC 30.65).

3 Study Methods This chapter summarizes the methods used to comply with the requirements set forth in SCC 30.62 for Critical Area Reporting. Critical areas were identified through a two-step process. HDR biologists first reviewed existing documents listed in Section 3.2. After this review, HDR biologists completed a thorough field investigation of the study area

Publically available maps listed in Section 3.2 were utilized for the evaluation of geologically hazardous areas, special flood hazard areas, and critical aquifer recharge areas.

3.1 Study Area The project study area is defined as the project corridor approximately 1.5 mile long by approximately 300 feet wide as required by SCC 30.91S.350. However, field investigations were limited to a 50-foot-wide corridor centered on the existing transmission line. Access on the east side of the project alignment was restricted due to the BNSF railroad right-of-way. Wetlands and FWHCAs outside of the study area were not formally delineated, but assessed based on characteristics visible from public rights-of-way or available information in existing documents and studies, maps, and/or aerial photographs.

3.2 Review of Existing Information HDR biologists reviewed the following existing environmental documents to determine the presence of critical areas in the project area:

USDA NRCS Web Soil Survey (USDA 2019)

U.S. Fish and Wildlife Service (USFWS) National Wetland Inventory Web Site (USFWS 2019a)

USFWS Information for Planning and Conservation (IPaC) Report (USFWS 2019b)



Washington State Department of Fish and Wildlife (WDFW) Priority Habitats and Species (PHS) on the Web (WDFW 2019a)

WDFW SalmonScape (WDFW 2019b).

DNR Washington Geologic Information Portal (DNR 2019a)

DNR Forest Practices Application Mapping Tool (DNR 2019b)

Snohomish County Critical Areas Mapping (2019)

These documents provide reference information on the soils, geotechnical hazards, hydrology, land use, wildlife habitat, wetlands, and streams in the project area.

3.3 Field Investigation Field investigations for the project were conducted by qualified HDR biologists. The field investigation consisted of an initial field reconnaissance followed by more detailed delineation of wetlands and streams in the 50-foot-wide field investigation area. HDR biologists conducted the field reconnaissance on December 15, 2015, and the field investigation on December 29, 2015, January 19 and 22, 2016, and February 2, 2016.

During the three months preceding field investigations (October 28 through December 28, 2015), the Arlington Municipal Airport, located approximately 2 miles east from the south end of the project, recorded a total of 9.3 inches of precipitation. Recorded precipitation levels in November and January were below normal, but the December precipitation level was within a normal range. During the two weeks prior to the start of field work (December 15 through 28, 2015), two inches of precipitation was recorded at the Arlington Municipal Airport. The average temperature recorded was around 40˚F at the Arlington Municipal Airport, which is slightly warmer than normal during this time of year (Weather Underground 2015).

3.3.1 Wetlands

Wetlands were identified through a two-step process. HDR staff first reviewed existing documents, including soil surveys, wetland and stream inventories, aerial photographs, and other reports listed in Section 3.1. After this review, HDR staff completed a thorough field investigation of the study area that included wetland verification, delineation, and classification.

Biologists delineated wetlands in the study area using the three parameter methods described in the US Army Corps of Engineers Wetland Delineation Manual (Environmental Laboratory 1987), as updated by the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys and Coast Region (USACE 2010). Areas were identified as wetlands if they met the necessary indicators for hydrophytic vegetation, hydrology, and hydric soils. A detailed description of the field methods used in this study is provided in Appendix A. Formal paired data plots were collected in each wetland identified within the study area. Data from all plots are also presented in Appendix A.

Delineated wetland boundaries and wetland data plot locations were marked in the field and locations were recorded using Trimble GEO XT and 7X GPS devices. This device is



capable of submeter accuracy. The resulting data were incorporated into project base maps.

Wetland Rating

Wetland ratings are used by regulatory agencies to help determine wetland buffers, mitigation replacement ratios and permitted uses in wetlands. Ratings are based on a wetland's sensitivity to disturbance, rarity within a region, functions, and values. Generally, wetlands that have not been altered significantly due to urbanization, have structural and spatial diversity, and those that are hydrologically connected to streams, have a higher rating.

Wetlands in the project study area were rated using the Washington State Wetland Rating System for Western Washington: 2014 Update, Washington State Department of Ecology Publication # 14-06-029 (Hruby 2014). Snohomish County also adopted Ecology’s new rating system; however, wetlands within their shoreline jurisdictions are classified by using the 2004 Ecology wetland rating system (Hruby 2004). Based on the discussion with the County reviewer (Scherf 2016), this project is using the 2014 Ecology’s rating system for all the wetlands within the study area to maintain consistency. Table 2 summarizes the 2014 Ecology rating criteria.

Wetland habitats identified in the study area were classified according to the system outlined by the USFWS in Classification of Wetlands and Deepwater Habitats of the United States (Cowardin 1979). The Cowardin system classifies wetlands based on their dominant vegetation structure and water regime.

.



Table 2. Wetland Rating System

Regulatory Agency Category

I II III IV

Washington State Department of Ecologya

Snohomish Countyb

Category I wetlands represent a unique or rare wetland type; or are more sensitive to disturbance than most wetlands; or are relatively undisturbed and contain ecological attributes that are impossible to replace within a human lifetime; or provide a high level of functions. Specific wetlands that meet the Category I criteria include:

Relatively undisturbed estuarine wetlands over one acre in size;

wetlands of High Conservation Value (formerly call national Heritage Wetlands), specifically,

wetlands identified by the Washington Natural Heritage Program/DNR as important ecosystems for maintaining plant diversity in our state;

bogs;

mature and old-growth forested wetlands over one acre in size;

wetlands in coastal lagoons;

interdunal wetlands that score 8 or 9 points for habitat, and are larger than one acre in size; and

wetlands scoring 23 points or more (out of 27) on the wetland rating form.

Category II wetlands are difficult, though not impossible, to replace, and provide high levels of some functions. Specific wetlands that meet the Category II criteria include:

Estuarine wetlands smaller than one acre in size, or disturbed estuarine wetlands larger than one acre;

wetlands scoring between 20-22 points (out of 27) on the wetland rating form; and interdunal wetlands larger than one acre that score 7 or lower for habitat, or those found in a mosaic of wetlands and dunes larger than 1 acre.

Category III wetlands provide a moderate level of functions and can often be adequately replaced with a well-planned mitigation project. Specific wetlands that meet the Category III criteria include:

Wetlands scoring between 16-19 points (out of 27) on the wetland rating form;

wetlands that can be adequately replaced with a well-planned mitigation project; and

interdunal wetlands between 0.1 acre and 1.0 acre in size.

Category IV wetlands have the lowest levels of functions and are often heavily disturbed. Specific wetlands that meet the Category IV criteria include: Wetlands scoring less than 16 points (out of 27) on the wetland rating form.

a Hruby (2014) b Snohomish County Code (SCC) 30.62A.230



3.3.2 Fish and Wildlife Habitat Conservation Areas

FWHCAs were identified through a two-step process. HDR staff first reviewed existing documents, including online stream inventories, aerial photographs, PHS data, and other reports that concern FWHCAs in the project vicinity. After this review, biologists completed a thorough field investigation of the study area that included stream identification, delineation, and classification and identification of other potential FWHCA’s in the study area.

Streams

To determine the ordinary high water mark (OHWM) of freshwater streams in the project area, HDR biologists utilized Ecology’s (Olsen and Stockdale 2010) guidance for OHWM identification, which is based on the Shoreline Management Act (RCW 90.58.030(2)(b) and Washington Administrative Code (WAC) 173-22-030(11).

HDR biologists looked for physical indicators including, but not limited to, a natural scour line impressed on the bank, distribution of upland and water tolerant vegetation, and bed and banks. The OHWM for identified streams within the study area was marked in the field and the locations were surveyed using the GPS device. The resulting data were incorporated into project base maps.

Snohomish County classifies streams based on the state’s stream tying system established in WAC 222-16-030. Criteria for this typing system are described in Table 3. Buffer widths were assigned to each stream based on the stream type described in Table 3. The stream types described in this report are based on the stream reaches within the study area; upstream reaches may be rated lower or higher.

Fish presence was determined through the review of previous studies, an assessment of the available habitat, the hydrologic condition of all identified surface waters, Forest Practices Application Mapping Tool (DNR 2019b), SalmonScape online maps (WDFW 2019b), and USFWS Listed and Proposed Endangered and Threatened Species and Critical Habitat in the study area (USFWS 2019b).



Table 3. Summary of the Water Typing System and Standard Riparian Buffer Widths for Snohomish County Streams

Water Type Definitiona

Snohomish County Riparian

Buffer Widthb

Type S Segments of all waters, within their bankfull width, as inventoried as "shorelines of the state" under chapter 90.58 RCW and the rules promulgated pursuant to chapter 90.58 RCW

150 feet

Type F

Segments of natural waters other than Type S waters, which are within the bankfull widths of defined channels or within lakes having a surface area of 0.5 acres or greater at seasonal low water, and which in any case contain fish habitat or are described by one of the following four categories: (a) Are diverted for domestic use by more than 10 residential or camping units or by a public accommodation facility licensed to serve more than 10 persons, where such diversion is determined by the Washington State Department of Natural Resources to be a valid appropriation of water and the only practical water source for such users. Such waters shall be considered to be Type F water upstream from the point of such diversion for 1,500 feet or until the drainage area is reduced by 50 percent, whichever is less; (b) Are diverted for use by federal, state, tribal or private fish hatcheries. Such waters shall be considered Type F water upstream from the point of diversion for 1,500 feet, including tributaries if highly significant for protection of downstream water quality; (c) Waters which are within federal, state, local or private campgrounds with more than 10 camping units: Provided that the water shall not be considered to enter a campground until it reaches the boundary of the park lands available for public use and comes within 100 feet of a camping unit, trail or other park improvement; (d) Riverine ponds, wall-based channels, and other channel features that are used by fish for off-channel habitat.

150 feet (salmonid bearing

stream)

100 feet (non-salmonid

bearing stream)

Type Np

Segments of natural waters within the bankfull width of defined channels that are perennial non-fish habitat streams. Perennial streams are waters that do not go dry any time of the year of normal rainfall. However, for the purpose of water typing, Type Np waters include the intermittent dry portions of the perennial channel below the uppermost point of perennial flow. Np waters begin downstream of the point along the channel where the contributing basin area is at least 52 acres in size.

50 feet

Type Ns

Segments of natural waters within the bankfull width of the defined channels that are not Type S, F, or Np waters. These are seasonal, non-fish habitat streams in which surface flow is not present for at least some portion of a year of normal rainfall and are not located downstream from any stream reach that is a Type Np water. Ns waters must be physically connected by an above-ground channel system to Type S, F, or Np waters.

50 feet

a WAC 222-16-030

b SCC 30.62A.320



3.3.3 Ditches All ditches were identified in the study area and determined if they were jurisdictional. Jurisdictional determination of ditches is based on criteria described in the joint memorandum, "Clean Water Act Jurisdiction Following the U.S. Supreme Court's Decision in Rapanos v. United States & Carabell v. United States," (signed December 2, 2008) issued by the U.S. Army Corps of Engineers (USACE) and the U.S. Environmental Protection Agency. Ditches are considered jurisdictional if a significant nexus can be identified using the following criteria (USACE 2007):

“Ditches excavated wholly in and draining only uplands and that do not carry a relatively permanent flow of water generally are not jurisdictional under the CWA, because they are not tributaries or they do not have a significant nexus to TNWs. If a ditch has relatively permanent flow into waters of the U.S. or between two (or more) waters of the U.S., the ditch is jurisdictional under the CWA. Even when not themselves waters of the United States, ditches may still contribute to a surface hydrologic connection between an adjacent wetland and a TNW.”

HDR biologists also looked for physical indicators including, but not limited to, areas showing scour marks or evidence of occasional flow, areas lacking vegetation, presence of a defined channel (bed/bank), and areas of flowing or standing water.

4 Results

4.1 Wetlands A total of two wetlands were identified within the study area: Wetland 13/3 in unincorporated Snohomish County, and Wetland 13/4 in the city of Stanwood (Figure 2). A summary of the characteristics of the wetlands is provided in Table 4. Descriptions of the wetlands delineated by HDR in the study area are provided in Tables 5 and 6. Formal paired data plots were assessed in each wetland, data from all plots are presented in Appendix A. Wetland Rating Forms are also included in Appendix A. Wetlands and buffers are shown on Figure 2.

Table 4. Summary of Wetlands Delineated in Study Area

Wetland Name

Hydro- geomorphic

Classificationa

Cowardin Classificationb

Approx. Acreage in Study Area

(Approx. total size)

Wetland Ratingc

Wetland Buffer (feet)d

13/3 Depressional PEM, PSS

3.86 (3.86) III

60

13/4 Depressional PEM, PSS 0.22

(0.22) III 75

a Hydrogeomorphic (HGM) classifications are based on A Hydrogeomorphic Classification of Wetlands (Brinson 1993). b Classification of Wetlands and Deepwater Habitats of the United States (Cowardin et al. 1979). PEM = Palustrine

Emergent, PFO = Palustrine Forested, POW = Palustrine Open Water, PSS = Palustrine Scrub/Shrub. c State Wetland Rating System for Western Washington (Hruby 2014). d Standard wetland buffer as specified in SCC 62A.340(4)(c).


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Table 5. Wetland 13/3 Summary

WETLAND 13/3 – INFORMATION SUMMARY

Location: Figure D-1 through D-3. Latitude: 48.23369, Longitude: -122.340427

Local Jurisdiction Snohomish County WRIA 5 Ecology Rating (Hruby, 2014)

III

Water Quality 7 Hydrologic 7 Habitat 4 Local Rating III Local Buffer Width 60 Wetland Size 3.86 Acres Cowardin Classification PEM/PSS HGM Classification Depressional

Wetland Data Sheet(s) SP 13/3-1, SP 12/4-1, SP

12/3-1, SP 12/3-2 Upland Data Sheet(s) SP 13/3-2 and SP 12/3-3

Dominant Vegetation

Nootka rose (Rosa Nutkana), willows (Salix, spp.) and reed canarygrass (Phalaris arundinacea) are the dominant plants present in Wetland 13/3. Vegetation in Wetland 13/3 meets criteria for hydrophytic vegetation.

Soils

Soils in Wetland 13/3 are mapped as Puget silty clay loam. Wetland 13/3 soils in sample plots generally consist of at least 9 inches of dark gray (2.5Y4/1) silt loam, dark grayish brown (2.5Y4/2, 2.5Y5/1) silty clay loam, grayish brown (2.5Y 5/2, 10YR 5/2) silty clay loam, or gleyed greenish gray (Gley 1 5/10Y) with redoximorphic features. Soils meet hydric soil indicators for a Depleted Matrix (F3) and a Loamy Gleyed Matrix (F2).

Hydrology

Primary sources of hydrology in Wetland 13/3 include irrigation runoff from adjacent agricultural fields and groundwater. At the northern portion of Wetland 13/3, overbank flooding from Irvine Slough provides some hydrology to the wetland. Wetland 13/3 meets wetland hydrology indicators for a Surface Saturation (A3) and a Water Table (A2).

Rationale for Delineation

The presence of all three wetland criteria. The boundaries of Wetland 13/3 were recorded with a GPS device where indicators of wetland vegetation, hydric soil and wetland hydrology were present.

Rationale for Local Rating

Wetland 13/3 is rated Category III using the current Ecology rating system because it provides moderate water quality (7), moderate hydrologic (7), and low habitat (4) functions, scoring 18 points on the wetland rating form.

Wetland Functions Summary

Water Quality

Wetland 13/3 has moderate potential to provide water quality functions. Wetland 13/3 receives untreated runoff from adjacent agricultural fields but has an unconstricted flowing outlet (Ditch13/3) which inhibits some water quality function. Wetland 13/3 is densely vegetated with emergent and herbaceous plants, and at least a quarter of the area is seasonally ponded.

Hydrologic

Wetland 13/3 has moderate potential to provide hydrologic functions due to a permanently flowing, slightly constricted outlet. Wetland 13/3 has some depth of storage during wet periods (marks of ponding were observed in the field). Surrounding land use activities provide moderate potential to support hydrologic functions.

Habitat

Wetland 13/3 has minimal potential to provide habitat functions due to its location in a developed landscape. Wetland 13/3 is adjacent to an agricultural field on the west and a railroad corridor on the east. Wetland 13/3 has riparian and in-stream priority habitats located at the north end of the wetland at Irvine Slough and Jorgenson Slough at the south end.


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Table 6. Wetland 13/4 Summary

WETLAND 13/4 – INFORMATION SUMMARY

Location: Figure D-1. Latitude: 48.240706, Longitude: -122.348495

Local Jurisdiction City of Stanwood WRIA 5 Ecology Rating (Hruby, 2014)

III

Water Quality 7 Hydrologic 6 Habitat 4 Local Rating III Local Buffer Width 75 feet Wetland Size 0.22 Acre Cowardin Classification PEM/PSS HGM Classification Depressional Wetland Data Sheet(s) SP 13/4X-1 Upland Data Sheet(s) SP 13/4X-2

Dominant Vegetation

Spirea (Spiraea douglasii) and reed canarygrass (are the dominant plants present in Wetland 13/4. Himalayan blackberry (Rubus armeniacus) is also present within the wetland. Vegetation in Wetland 13/4 meets criteria for hydrophytic vegetation.

Soils

Soils in Wetland 13/4 are mapped as Puget silty clay loam. Wetland 13/4 soils consist of at least 16 inches of very dark gray (10YR3/1) gravely loamy sand. Soils are restricted after 16 inches due to compacted gravel. Soils in wetland were likely altered due to its proximity to the rail road tracks. Sample plot meets criteria for hydric soil because it tested positive for reduced iron using alpha, alpha-dipyridyl strips.

Hydrology

Primary sources of hydrology in Wetland 13/4 include runoff from 84th Avenue, direct precipitation, and ground water. Wetland 13/4 meets wetland hydrology indicators for a High Water Table (A2) and a Surface Saturation (A3). Surface water was also present within the wetland.

Rationale for Delineation

The presence of all three wetland criteria. The boundaries of Wetland 13/4 were recorded with a GPS device where indicators of wetland vegetation, hydric soil and wetland hydrology were present.

Rationale for Local Rating

Wetland 13/4 is rated Category III using the current Ecology rating system because it provides moderate water quality (7), moderate hydrologic (6), and low (4) habitat functions, scoring 17 points on the wetland rating form.

Wetland Functions Summary

Water Quality

Wetland 13/4 has a moderate potential to improve water quality. Wetland 13/4 is vegetated with ungrazed dense herbaceous vegetation and receives untreated runoff from 84th Avenue. Wetland 13/4 drains into a catch basin located on 84th Avenue NW and likely drains into Irvine Slough which is on the 303(d) list for bacteria.

Hydrologic

Wetland 13/4 has a moderate potential to reduce flooding and erosion due to an intermittently flowing outlet that allows surface water to flow from the wetland. Wetland 13/4 has some storage availability during wet periods as marks of ponding were visible during the field visit. Surrounding land use activities provide high potential to support hydrologic functions.

Habitat

Wetland 13/4 has limited wildlife habitat potential due to its small size and location. There is no accessible habitat from the surrounding landscape because the wetland is isolated by roadways, a railroad, and commercial land uses. Priority habitats identified by WDFW within 330 feet of the wetland include riparian and in-stream areas associated with Irvine Slough.


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4.2 Fish and Wildlife Habitat Conservation Areas

4.2.1 Waterbodies

The study area is located in the Stillaguamish River-Frontal Port Susan basin (HUC10) of the Stillaguamish River (WRIA #5). No lakes or marine waters are located in the study area. HDR biologists delineated the OHWMs of two streams within the study area: Irvine Slough (in the city of Stanwood), and Jorgenson Slough (in unincorporated Snohomish County). Table 7 summarizes the streams and their jurisdictional classifications, and a description of each stream is summarized in Tables 8 and 9. Snohomish County designates rivers or streams with a mean annual flow greater than 20 cubic feet per second and associated floodways and floodplains. The majority of the project area is located in the 100-year floodplain.

Table 7. Summary of Streams in the Project Study Area (from North to South)

Stream Name Tributary To Local Stream

Rating in Study Areaa

Jurisdiction

Local Jurisdiction

Stream Buffer Width (feet) b

Irvine Slough Old Stillaguamish River Divergence

2 City of

Stanwood 150

Jorgenson Slough

Old Stillaguamish River Divergence

S Snohomish

County 150

a Stream types were assigned based on the typing criteria described in SCC 30.62A.320 and SMC 17.13.060. Fish presence was determined based on Salmonscape (WDFW 2015a) and field observation.

b Buffer widths are assigned based on stream types per SCC 30.62A.320 and SMC 17.13.060.

Table 8. Stream information summary—Irvine Slough STREAM INFORMATION SUMMARY

Stream Name Irvine Slough WRIA 5 WA Stream Catalog # 50014 Local Jurisdiction City of Stanwood DNR Stream Type F Local Stream Rating 2 Buffer Width 150 feet Documented Fish Use

Modeled presence: Fall Chinook Salmon, Coho, fall Chum, winter steelhead, and Pink Salmon

Location of Stream Relative to Project Corridor

Irvine Slough is located at the northern end of the project alignment, north end of Wetland 13/3 and south of SR 532. The stream channel is approximately 4 feet wide.

Connectivity (where stream flows from/to)

Irvine Slough is a tributary of the Old Stillaguamish River Divergence and flows east to west through the project area. The slough flows through a 30-inch concrete culvert under the BNSF railroad track, flows through Wetland 13/3, and crosses Marine Drive NW through two 18-inch concrete culverts.

Riparian/Buffer Condition

Riparian vegetation is dominated by reed canarygrass, and no shrubs and trees are located along the stream channel in the study area.


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Table 9. Stream information summary—Jorgenson Slough STREAM INFORMATION SUMMARY

Stream Name Jorgenson Slough WRIA 5 WA Stream Catalog # 50018 Local Jurisdiction Snohomish County DNR Stream Type F Local Stream Rating S Buffer Width 150 Documented Fish Use

Modeled presence: Fall Chinook Salmon and Pink Salmon Documented presence: Coho, fall Chum, and winter steelhead Presumed presence: Bull Trout

Location of Stream Relative to Project Corridor

Jorgenson Slough is located at Pole 12/2 and east of Wetland 13/3. Jorgenson Slough is approximately 80 feet wide within the study area.

Connectivity (where stream flows from/to)

Jorgenson Slough is a tributary of the Old Stillaguamish River Divergence and flows northeast to southwest through the project area.

Riparian/Buffer Condition

Jorgenson Slough runs through an active agricultural field, and riparian vegetation in the study area is mostly dominated by reed canarygrass. No canopy cover or large woody debris was present in the study area.

Ditches

In addition to streams, HDR biologists identified one ditch within the study area. Ditch 13/3 is an artificially constructed ditch that appears to be actively maintained for irrigation, and it is not physically connected by an above-ground channel system to Type S, F, or Np waters.

Table 10 provides a summary of Ditch 13/3 in the study area.

Table 10. Summary of Ditches in the Project Study Area

Ditch Name

Length (feet)

Width (feet)

Location Source Discharge Location

Jurisdiction

Ditch 13/3 3,900 7 Between Pole 13/1 and 12/4

Irrigation and Floodplain

Jorgenson Slough

Snohomish County

4.2.2 Federal and State Threatened and Endangered Species

The USFWS IPaC database (USFWS 2019b) list the following federally listed threatened species as having the potential to occur in the project study area:


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Table 11. Federally listed Species in the Study Area

Species Listing Status

(Federal, State) Agency Critical Habitat

Marbled Murrelet (Brachyramphus marmoratus)

Threatened, Endangered

USFWS WDFW

Designated but not in study area

Streaked Horned Lark (Eremophila alpestris strigata)

Threatened Endangered

USFWS WDFW


Yellow-billed Cuckoo (Coccyzus americanus)

Threatened Endangered

USFWS WDFW


Fall Chinook (Oncorhynchus tshawytscha)

Threatened NMFS None in study area

Winter Steelhead (Oncorhynchus mykiss)

Threatened NMFS None in study area

Bull Trout (Salvelinus confluentus)

Threatened, Candidate

NMFS WDFW


MARBLED MURRELET

Murrelets are small seabirds that spend the majority of their lives in the marine environment, returning to old-growth or mature forest stands for nesting. Most nests are in conifers over 150 years old, and in trees greater than 55 inches diameter at breast height. Marbled murrelet distribution in Washington includes mature forest stands throughout the Cascades. WDFW PHS data (2019a) indicates that there are no occurrences of marbled murrelets or their habitat within the project corridor and vicinity. Given the project location between Puget Sound and inland nesting areas in the Cascades to the east, there is the potential that a few marbled murrelets could fly over the project area while transiting between marine foraging areas and inland nesting sites. However, due to the lack of mature trees for nesting within the study area, the project will not result in impacts to marbled murrelets or their habitat.

STREAKED HORNED LARK

In Washington, streaked horned larks are found on prairie and grassland south of Puget Sound, coastal beaches, and islands and sparsely vegetated shoreline sites on the lower Columbia River. Their habitat consists of large expanses of bare or sparsely vegetated land, including fields, prairies, upper beaches, airports, and similar areas with low/sparse grassy vegetation. WDFW PHS data (2019a) indicates that there are no occurrences of streaked horn lark or their habitat within the project corridor and vicinity. However, due to the location of the corridor near agricultural fields, streaked horned lark have the potential to occur near the project.

YELLOW-BILLED CUCKOO

Yellow-billed cuckoos display a strong preference for large, continuous riparian zones with cottonwoods and willows. In Washington, nesting also took place in fir woodlands


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and open brushy hillsides. WDFW PHS data (2019a) indicates that there are no occurrences of yellow-billed cuckoo or their habitat within the project corridor and vicinity.

BULL TROUT

Bull Trout in the Stillaguamish River are part of the coastal and Puget Sound Distinct Population Segment (DPS), and was federally listed as threatened under the Endangered Species Act (ESA) in 1999. The USFWS defined a single DPS for Bull Trout within the coterminous United States and listed them as threatened under the ESA in 1999 (64 FR 58910). Bull trout are known to use the Stillaguamish River, but are not documented in Jorgenson Slough (WDFW 2019b). Although there is no record of Bull Trout presence in slough, it is conservatively assumed that Bull Trout may be present within Jorgenson Slough due to the existence of potential habitat.

CHINOOK SALMON

Fall Chinook Salmon have a modeled presence in Jorgenson Slough. The Puget Sound Evolutionary significant Unit (ESU) of Chinook Salmon was listed as a federally threatened species on March 24, 1999, and reaffirmed in 2005. The Puget Sound Chinook Salmon ESU includes all marine, estuarine, and river reaches that are accessible to listed Chinook Salmon in the Puget Sound.

STEELHEAD

The Puget Sound DPS of steelhead was listed as threatened under the ESA on May 11, 2008. Puget Sound steelhead exhibit one of the most complex suites of life history strategies among anadromous Pacific salmonid species. Unlike other anadromous salmonids, steelhead can spawn multiple times, often returning to marine waters between freshwater spawning bouts (Busby et al. 1996). Juvenile Puget Sound steelhead typically rely heavily on freshwater habitats and may spend multiple years in freshwater before migrating (NMFS 2005). Winter steelhead have a documented presence in Jorgenson slough (WDFW 2019b).

4.2.3 State Designated Priority Habitats and Species

The WDFW PHS database identifies several salmonid species that are documented to be present in Jorgenson Slough. These include Coho, fall Chum, and winter steelhead. In addition, the WDFW PHS database show winter concentration areas for trumpeter swans (WDFW 2019a). The concentration areas are located in the active agricultural fields.

4.2.4 State Listed Sensitive Species

The geographic range and required habitat for state listed sensitive species was reviewed to determine their likely presence in the study area.

Larch Mountain salamander. Larch Mountain salamanders are associated with talus, scree, gravelly soils and other areas of accumulated rock where interstitial spaces exist between the rock and soil. Steep slopes are also an important habitat feature. This habitat does not occur in the study area; therefore, the presence of Larch Mountain salamander in the study area is unlikely (WDFW 2019d).


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Common loon. Common loons usually nest on lakes surrounded by forest that have deep inlets and bays. Lakes where loons nest in Washington range in size from 14 to 7,800 acres. This habitat does not occur in the study area; therefore, the presence of common loon is the study area is unlikely (WDFW 2012a)

Peregrine falcon. Peregrine falcons breed on cliffs, and occasionally tall buildings, bridges, and other locations that offer security and a vantage point above surrounding terrain. The highest population densities are along the northern outer coast and San Juan Islands. They are also found in Cascade Range foothills, along the Columbia River, and in other water bodies within the Columbia Basin. Peregrine falcons are an uncommon resident, migrant, and wintering species in western lowlands. They hunt primarily in areas of open cover types that include estuaries, agricultural fields, coastal beaches, water bodies, and in some urban areas (WDFW 2019e). Peregrine falcons may be present but unlikely to be found in the project area.

Olympic mudminnow. Olympic mudminnows are found in the southern and coastal drainages of the Olympic Peninsula, the Chehalis river basin, south Puget Sound west of the Nisqually River, and a few sites in south Snohomish and King counties (WDFW 2019f). There have been no recorded occurrences of Olympic mud minnows near the project area (WDFW 2019f).

Pygmy Whitefish are most commonly found in cool oligotrophic lakes and streams of mountainous regions, and currently inhabit only nine lakes in Washington. Suitable Pygmy Whitefish habitat does not occur in the study area; therefore, their presence is unlikely (WDFW 2019g).

Gray whale. Habitat for this species does not occur near the study area (WDFW 2019h).

Margined sculpin. The margined sculpin is only found in southeastern Washington; therefore, their presence is unlikely in the study area (WDFW 2012b).

4.3 Geologically Hazardous Areas Below is a summary of potential geologic hazards at the site, based on a review of the publically available data sources listed in Section 3.2.

Erosion Hazards: Based on the USDA NRCS Web Soil Survey (USDA 2019) for the project corridor, soils are not at a high risk for water erosion. The project corridor is not located near the shoreline of a waterbody that is subject to wind and wave erosion.

Channel Migration Zone (CMZ): The North Fork of the Stillaguamish River is mapped as a river channel subject to migration (SCC 30.62B.330(1)). However, per SCC 30.62B.330(3)(b)(1), utilities are exempt from County CMZ standards and requirements.

Landslide Hazards: According to the Washington Department of Natural Resources Geologic Portal (DNR 2019) and the Snohomish County Planning and Development Services Map Portal (Snohomish County 2019), the project corridor is not located near a mapped landslide hazard.


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Seismic Hazards. The project corridor is mapped as having a low to moderate and moderate to high liquefaction susceptibility (DNR 2004)

Volcanic Hazards: The project corridor is located in the Stillaguamish River Valley, which is located with the lahar hazard zone for Glacier Peak (Snohomish County 2019).

Mine Hazards: No active or abandoned mines are mapped in or near the project corridor (Snohomish County 2019, DNR 2019).

4.4 Aquifer Recharge Areas According to the Snohomish County Critical Aquifer Recharge Areas Map (Snohomish County 2016), the project corridor is located in an area of low to moderate aquifer sensitivity. The project corridor is not located near a US Environmental Protection Agency (EPA) designated sole source aquifer (Snohomish County 2016) or within a 10-year travel zone of a Group A wellhead protection area (DOH 2019).

4.5 Special Flood Hazard Areas According to the Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map Community Panels Number 53061C0351E and 53061C0352E, the project corridor is located within Zone AE within the Special Flood Hazard Areas inundated by the 100-year flood.

5 Impacts Activities from the proposed project that are expected to affect critical areas are analyzed in the following sections. According to SCC 30.62A.330(2)(c) and 30.62A.340(3)a), the new utilities are allowed in wetlands and fish and wildlife habitat conservation areas when located within the developed footprint of the existing utility crossings, and where no other feasible alternative exists.

5.1 Wetlands and Wetland Buffer Impacts Because poles would be replaced along the existing alignment and since these poles will maintain the existing spacing, impacts to wetlands and their buffers are unavoidable but have been minimize to the extent possible. Currently, two poles are located within wetlands and eight poles are located within the wetland buffer in the Snohomish County portion of the project. As part of the project, two poles would be replaced within the wetlands, and ten poles would replace eight poles currently located within the wetland buffer.

Existing poles that would be replaced occupy an approximately 2-foot-diameter circle, or 3.14 square feet per pole. Replacement poles would be located within a 3-foot-diameter caisson which would result in an additional 3.92 square feet of permanent impact area for each pole. See Table 12 for the total permanent wetland and buffer impacts in Snohomish County.


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Table 12. Snohomish County Wetland and Buffer Impacts

Wetland Name Permanent

Wetland Impacts (square feet)

Permanent Buffer Impacts

(square feet)

Wetland 13/3 1.56 sq ft 36.7 sq ft

5.2 Fish and Wildlife Habitat Conservation Areas

5.2.1 Waterbodies and Buffers

Jorgenson Slough

No poles would be placed within or removed from Jorgenson Slough or its buffer.

5.2.2 Threatened, Endangered and Sensitive Species

Due to a lack of appropriate habitat in the study area, marbled murrelet and yellow-billed cuckoo are unlikely to occur in the study area, and therefore, unlikely to be impacted by the project. Although streaked-horned lark have the potential to occur in the study area, impacts are unlikely. Poles would be placed within the existing easement and the easement is regularly cleared as part of vegetation management requirements.

No poles would be placed within Jorgenson Slough, and no in-water work or stream crossings are proposed for construction. A temporary erosion and sediment control plan will be developed to minimize the potential for erosion and exposed soils will be stabilized following construction. Therefore, impacts to Bull Trout, Chinook Salmon or steelhead in Jorgenson Slough are not anticipated. Peregrine falcon may occur but are unlikely to occur in the project area. The existing/new line has avian protection measures in place; therefore, impacts to peregrine falcons are unlikely to occur.

5.3 Special Flood Hazard Areas The project is located with a special flood hazard area. However, pursuant to SCC 30.65.200(2)(a), caissons will be utilized at the base of the poles to provide flood proofing and support to the new poles. Therefore, no impacts are anticipated.

5.4 Critical Aquifer Recharge Areas The project corridor is located in an area of low to moderate aquifer sensitivity. However, the project does not involve an activity or use that may impact water quality; therefore, no impacts are anticipated.

5.5 Geologically Hazardous Areas The project would be located the Stillaguamish River Valley, which is located with the lahar hazard zone for Glacier Peak. However, lahars in the Stillaguamish River Valley are unlikely since they would only occur which would occur only if the Sauk River became choked with enough debris to be diverted west into the Stillaguamish River valley (USGS 2019). Therefore no impacts from lahars are anticipated.


19 | February 7, 2020

The project corridor is mapped as having a low to moderate and moderate to high liquefaction susceptibility. The project would not increase the likelihood of seismic hazards.

6 Mitigation According to SCC 30.62A.310, Snohomish County requires the mitigation efforts to follow the prescribed sequence:

1. Avoiding the impact altogether by not taking a certain action or part of an action;

2. Minimizing impacts by limiting the degree or magnitude of the action and its implementation, using appropriate technology, or by taking affirmative steps, such as project redesign, relocation, or timing, to avoid or reduce impacts; and mitigating for the affected functions and values of the critical area;

If mitigation is required, mitigation is required in-kind and on site.

SCC 30.62A.320(2)(a) allows for new utilities within buffers when no other feasible alternative exists or the location, design and construction minimizes impacts to the buffers. The poles would be replaced within the District’s existing easement. The District’s easement is regularly cleared as part of vegetation maintenance requirements, and surrounding lands in use as agriculture are also cleared. No temporary or permanent access road construction within wetlands or wetland buffers will be constructed for this project. All work will be conducted from either the existing paved surface or from temporary construction work areas that will be removed and restored following construction. Any access for work within wetlands or wetland buffer areas will use mats to support the equipment and will not require clearing and grubbing of vegetation. Poles within a wetland or wetland buffer will typically require a temporary work area with an approximately 10-foot radius around the pole. A temporary erosion and sediment control plan will be developed to minimize the potential for erosion and all exposed soils will be stabilized following construction.

No trees are planned to be impacted the project. Some overgrown brush located around some of the existing poles may be impacted to access the work locations. The District’s easement is regularly cleared as part of vegetation maintenance requirements, and surrounding lands in use as agriculture are also cleared.

Temporary wetland disturbance due to construction will be minimized by careful planning and minimization measures designed to limit ground disturbance to only the areas needed to complete the pole installations. Equipment needed to install each of the poles in wetlands will operate from wetland mats that lay directly over the existing vegetation and ground surface. These methods will minimize the need to excavate or disturb soils near the poles during installation and reduce the need for restoration of soil and plant cover following construction. Following pole installation, disturbed areas within wetlands will be reseeded with an appropriate native seed mix.

Since the impacts to wetlands and wetland buffers are minimal and since care has been taken in the planning of the project to avoid direct wetland impacts wherever feasible, and since best management practices will be followed and monitored during pole installation for this project, no compensatory mitigation is warranted or proposed.


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7 References Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of Wetlands

and Deepwater Habitats of the United States. Government Printing Office, Washington, D.C.

DNR (Washington Department of Natural Resources). 2019b. Forest Practices Application Mapping Tool. https://fortress.wa.gov/dnr/protectiongis/fpamt/ Accessed October 31, 2019.

DNR. 2004. Liquefaction Susceptibility Map of Snohomish County, Washington. September 2004. Available online: ftp://ww4.dnr.wa.gov/geology/pubs/ofr04-20/ofr2004-20_sheet61_snohomish_liq.pdf. Access October 29, 2019.

DNR. 2019a. Washington Geologic Information Portal. Available online: https://geologyportal.dnr.wa.gov/#natural_hazards. Accessed October 29, 2019.

Environmental Laboratory. 1987. Corps of Engineers Wetland Delineation Manual. Technical Report Y-87-1. Department of the Army, Waterways Experiment Station. Vicksburg, Mississippi.

Hruby, T. 2014. Washington State wetland rating system for Western Washington: 2014 Update. Washington State Department of Ecology Publication #14-06-029. Olympia, Washington: Washington Department of Ecology.

Olson, P. and E. Stockdale. 2010. Determining the Ordinary High Water Mark on Streams in Washington State. Second Review Draft. Washington State Department of Ecology, Shorelands & Environmental Assistance Program, Lacey, Washington. Ecology Publication # 08-06-001.

Scherf, F. 2016. Personal communication between Frank Scherf, Snohomish County, and Maki Dalzell, HDR. February 10, 2016.

Snohomish County. 2019. Snohomish County Critical Aquifer Recharge Areas. February 1, 2016. Available online: http://www.snoco.org/docs/scd/PDF/PDS_CAR/ Critical_Aquifer_Recharge_Areas_ALLCounty_20160201.pdf. Accessed October 29, 2019.

Snohomish County. 2019. Snohomish County Planning and Development Services (PDS) Map Portal. Available online: http://gismaps.snoco.org/Html5Viewer/Index.html?viewer=pdsmapportal&layertheme=Critical%20Areas. Accessed October 29, 2019.

Stalmaster, M.V. 1987. The Bald Eagle. Universe Books, New York, New York. 227 pp.

USACE (U.S. Army Corps of Engineers). 2007. Jurisdictional Determination Form Instructional Guidebook. http://www.usace.army.mil/Portals/2/docs/civilworks/regulatory/cwa_guide/jd_guidebook_051207final.pdf.

USACE (U.S. Army Corps of Engineers). 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys and Coast Region. ERDC/EL TR-10-3.


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http://www.usace.army.mil/CECW/Documents/cecwo/reg/west _mt_finalssupp.pdf.

USDA, NRCS. (U.S. Department of Agriculture, Natural Resources Conservation Service). 2019a. Web Soil Survey. Available online: http://websoilsurvey.sc.egov.usda.gov/App/ WebSoil Survey.aspx. Accessed October 29, 2019.

USFWS (U.S. Fish and Wildlife Service). 2019a. National Wetland Inventory. Wetlands Online Mapper. Available online: http://www.fws.gov/wetlands/Data/Mapper.html.Accessed November 1, 2019.

USFWS (U.S. Fish and Wildlife Service). 2019b. Customized IPaC Trust Resource Report. Generated October 2019. https://ecos.fws.gov/ipac/

Washington State Department of Health. 2019. Source Water Assessment Program Mapping Application. Available online: https://fortress.wa.gov/doh/swap/index.html. Accessed October 29, 2019.

WDFW (Washington State Department of Fish and Wildlife). 2019b. SalmonScape. http://wdfw.wa.gov/mapping/salmonscape Accessed October 31, 2019.

WDFW. 2012. Margined Sculpine. Available online: https://wdfw.wa.gov/sites/default/files/2019-03/margined_sculpin.pdf. Accessed October 31, 2019.

WDFW. 2012a. Common Loon. Available online: https://wdfw.wa.gov/sites/default/files/2019-03/common_loon.pdf. Accessed October 31, 2019.

WDFW. 2019c. Streaked Horned Lark. Available online: https://wdfw.wa.gov/species-habitats/species/eremophila-alpestris-strigata. Accessed October 31, 2019.

WDFW. 2019d. Larch Mountain Salamander. Available online: https://wdfw.wa.gov/species-habitats/species/plethodon-larselli. Accessed November 1, 2019.

WDFW. 2019e. Peregrine Falcon. Available online: https://wdfw.wa.gov/species-habitats/species/falco-peregrinus. Accessed October 31, 2019.

WDFW. 2019f. Olympic Mudminnow. Available online: https://wdfw.wa.gov/sites/default/files/2019-03/olympic_mudminnow.pdf. Accessed October 31, 2019.

WDFW. 2019g. Pygmy Whitefish. Available online: https://wdfw.wa.gov/sites/default/files/2019-03/pygmy_whitefish.pdf. Accessed October 31, 2019.

WDFW. 2019h. Gray Whale. Available online: https://wdfw.wa.gov/species-habitats/species/eschrichtius-robustus. Accessed October 31, 2019.

Weather Underground. 2015. Historic Weather Data for Silvana, Washington. https://www.wunderground.com/history/airport/KAWO/2016/7/28/DailyHistory.html?FULLALMANAC=KAWO . Accessed December 2015.


February 7, 2020

Appendix A. Wetlands and Fish and Wildlife Conservation

Areas Report