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HomeMy WebLinkAboutRS_Critical_Areas_Report_190116_v2
R E N T O N C R I T I C A L A R E A S R E P O R T
(I n c l u d i n g W e t l a n d A s s e s s m e n t , S t r e a m
S t u d y , a n d W i l d l i f e / H a b i t a t A s s e s s m e n t )
Puget Sound Energy – Energize
Eastside Project
Prepared for:
Bradley Strauch
PSE Energize Eastside
355 110th Avenue NE
Bellevue, WA 98004
Prepared by:
Revised January 2019
The Watershed Company Reference Number:
111103.8
The Watershed Company Contact Person:
Jennifer Creveling, Senior Biologist
Katy Crandall, Ecologist / Arborist
Or Clover McIngalls, Environmental Planner
Cite this document as:
The Watershed Company. Revised January 2019. City of
Renton Critical Areas Report: Puget Sound Energy –
Energize Eastside Project. Prepared for PSE.
The Watershed Company
Revised January 2019
i
T ABLE OF C ONTENTS
Page #
1 Executive Summary............................................................................ 1
2 Introduction and Project Description ............................................... 2
3 Methods ............................................................................................... 4
3.1 Study Area ........................................................................................................... 5
3.2 Data Compilation ................................................................................................. 5
3.3 Project Element Construction – Potential Impacts ............................................... 6
Pole Replacement ............................................................................................... 6
Access routes ...................................................................................................... 8
Stringing Sites ...................................................................................................... 9
Vegetation Management...................................................................................... 9
3.4 Critical Areas Impact Analysis............................................................................ 11
3.5 Limitations ......................................................................................................... 11
4 Existing Conditions .......................................................................... 12
4.1 Site Location ...................................................................................................... 12
4.2 Site Description ................................................................................................. 12
4.3 Critical Areas ..................................................................................................... 13
Wetlands ............................................................................................................ 13
Streams and Lakes ............................................................................................ 14
Habitat Conservation Areas ............................................................................... 15
Flood Hazard Areas ........................................................................................... 23
Geologic Hazard Areas...................................................................................... 23
Wellhead Protection Areas ................................................................................ 25
4.4 Shorelines of the State ...................................................................................... 26
5 Regulations ....................................................................................... 28
5.1 Critical Areas Regulations Exemption ................................................................ 28
5.2 Critical Area Buffers ........................................................................................... 29
Wetlands and Streams ...................................................................................... 29
Habitat Conservation Areas ............................................................................... 32
Geologic Hazard Areas...................................................................................... 32
5.3 Shoreline Master Program Regulations ............................................................. 33
6 Mitigation Sequencing ..................................................................... 33
7 Unavoidable Project Impacts .......................................................... 35
7.1 Critical Area Impacts .......................................................................................... 37
Wetland and Stream Buffer Impacts .................................................................. 37
Habitat Conservation Area Impacts ................................................................... 39
Geologic Hazard Area Impacts and Associated Buffer Impacts ....................... 39
Wellhead Protection Area Impacts .................................................................... 40
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8 Mitigation Approach ......................................................................... 41
8.1 Wetland and Stream Buffer Mitigation Ratio ...................................................... 41
8.2 Wetland and Stream Buffer Mitigation Location ................................................. 42
9 Mitigation Plan .................................................................................. 42
9.1 Wetland and Stream Buffer Mitigation................................................................ 42
9.2 Geologic Hazard Area Mitigation ....................................................................... 44
10 Functional Lift Analysis ................................................................... 45
May Creek Sub-basin ........................................................................................ 47
Lower Cedar River Sub-basin ........................................................................... 48
11 Disclaimer .......................................................................................... 50
Appendix A
Critical Area Assessment Maps
Appendix B
2016 Delineation Study
Appendix C
2017 Delineation Study Update
Appendix D
Detailed CAIA Methodology
Appendix E
Geological Hazards Report
Appendix F
Mitigation Plan
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Revised January 2019
iii
L IST OF F IGURES
Figure 1. Map of Energize Eastside Project route in Renton and limits of the Critical Area
Impact Assessment. ................................................................................. 4
L IST OF T ABLES
Table 1. PSE construction scenarios. .............................................................................. 7
Table 2. State-listed wildlife species, excluding those listed as federally endangered and
threatened. ............................................................................................. 16
Table 3. Excerpt of RMC 4-3-050.C.3 table of exempt activities. ................................... 28
Table 4. Summary of wetland critical area classifications and standard buffer widths. ... 30
Table 5. Summary of stream critical area classifications and standard buffer widths. .... 30
Table 6. Summary of geologic hazard area buffer requirements.................................... 32
Table 7. Matrix used for determining impact types based upon long-term condition of
proposed activities and existing land cover types in critical areas and
associated buffers. ................................................................................. 36
Table 8. Wetland and stream buffer impacts by wetland and/or stream feature and sub-
basin. ..................................................................................................... 38
Table 9. Geologic hazard area impacts associated with pole replacement in Project area.
............................................................................................................... 39
Table 10. Vegetation conversion impacts to geologic hazard areas in the Project area. 40
Table 11. Actions within wellhead protection areas in the Project area. ......................... 41
Table 12. Calculation of mitigation needs for wetland and stream functioning buffer
impacts. ................................................................................................. 43
Table 13. Descriptions of general impact area conditions and proposed changes. ........ 46
The Watershed Company
Revised January 2019
1
C ITY OF R ENTON C RITICAL
A REAS R EPORT
P UGET S OUND E NERGY – E NERGIZE E ASTSIDE
1 E XECUTIVE S UMMARY
PSE’s Energize Eastside Project (the Project) proposes to upgrade existing
transmission lines in the city of Renton in order to increase transmission system
capacity to 230kV power. The Project is needed to address electrical system
deficiencies identified during federally required planning studies and to improve
electrical supply and reliability to Eastside communities, including Renton, now
and in the future.
Regulated critical areas present in the Project area include wetlands, streams, and
associated buffers; habitat conservation areas; flood hazard areas; geologic
hazard areas (i.e., steep slopes, landslide hazards, erosion hazards, seismic
hazards, and coal mine hazards); and wellhead protection areas. A portion of the
Project area also lies within the shoreline jurisdiction of the Cedar River. Project
activities qualify as exempt from Renton critical area regulations. The Project was
designed to avoid and minimize impacts to critical areas in accordance with the
City’s exemption criteria by utilizing the existing transmission line corridor,
limiting disturbance and implementing best management practices (BMPs) when
working in critical areas, and installing transmission lines between poles with
minimal site disturbance.
No new poles are proposed in wetlands, streams or stream buffers, flood hazard
areas, or seismic hazard areas. New poles are proposed in erosion hazard areas,
landslide hazard areas, steep slope hazard areas, coal mine hazard areas, habitat
conservation areas and wellhead protection areas. These new poles will not
significantly impact respective critical area functions.
In wetland buffers, permanent impacts (i.e., poles) are limited to one new
Energize Eastside pole and three Lake Tradition replacement poles. The Lake
Tradition poles are being replaced in the same location as existing poles, but the
replacement poles have a larger footprint than the existing poles. Two existing
poles will also be removed from and replaced outside of wetland and stream
buffer resulting in a net increase of only 68 square feet of permanent wetland
buffer impact. Vegetation community conversion impacts in wetland and stream
PSE Energize Eastside Project
Renton Critical Areas Report
2
buffers total 18,786 square feet and 19,235 SF square feet of temporary
disturbance will occur. Vegetation conversion impacts are also proposed in
erosion hazard areas, landslide hazard areas, steep slope hazard areas, coal mine
hazard areas, habitat conservation areas and wellhead protection areas.
The majority of wetland/stream critical area impacts, which are primarily limited
to buffer impacts from vegetation management (i.e., tree removal) occur in the
Lower Cedar River sub-basin. Mitigation for critical areas impacts will be
focused in this sub-basin, specifically in the buffer of Wetland NR01 (see the
Mitigation Plan). Additionally, creation of standing snags will occur near Honey
Dew Creek, within the May Creek sub-basin.
This report is intended to support the City of Renton’s critical area review
process and to satisfy the exemption criteria of the Renton Municipal Code
(RMC) 4-3-050.C.3 – Critical Area Regulations.
2 I NTRODUCTION AND P ROJECT
D ESCRIPTION
Puget Sound Energy, Inc. (“PSE”) proposes the construction of a new 230 kV to
115 kV substation (Richards Creek Substation in Bellevue) and to upgrade
approximately 16 miles of existing 115 kV transmission lines located within an
approximately 100-foot wide regional utility corridor to accommodate 230 kV
power (collectively “the Project”). The Richards Creek Substation will be built to
accommodate the 230kV to 115kV transformer needed to accommodate the
transmission line upgrade, which is necessary to address a deficiency in electrical
transmission capacity during peak periods. Combined with aggressive
conservation, the Project will improve reliability for Eastside communities,
including the city of Renton (“Renton” or “City”), and supply the needed
electrical capacity for anticipated growth and development on the Eastside.
Within Renton, the Project corridor extends north-south for approximately 4
miles (Figure 1). The proposal for the Energize Eastside Project includes the
removal of 144 existing poles and installation of 41 new poles. Existing and
proposed pole locations are shown on the maps in Appendix A.
PSE owns and operates an existing 115 kV transmission line between the Talbot
Hill substation in Renton and the Lake Tradition substation in Issaquah (Talbot
Hill - Lake Tradition #1). To better accommodate the Project, a short section of
the Lake Tradition #1 line will “trade” places with one of the Lakeside -Talbot
Hill 115 kV lines, which will be rebuilt to 230 kV as part of the Project. This
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Revised January 2019
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relocation work will take place within PSE’s existing easement near the Shadow
Hawk condominiums on parcel #7701590000. (Refer to Appendix A for pole
locations.) The work will include replacement of the existing three-pole wood
turning structure (115-5) that is situated on the Shadow Hawk property. The 115
kV conductor will then be “jumpered” for one span underneath the new 230kV
lines to another replacement three-pole wood structure (115-4). One new two-
pole wood structure (115-3) will be added to provide additional wire clearance
for the existing 115 kV conductor just east of the corner structures (115-4 and 115-
5). Additionally, two of the existing three-pole wood structures (115-1 and 115-2)
north of the Talbot Hill substation on the Talbot Hill – Lake Tradition #1 line will
be replaced with similar structures as part of general maintenance and repair due
to the poor condition of the existing structures. The existing overhead 115 kV
conductors (wires) will remain in place and be reattached to the new and
replacement wood pole structures. This work will maintain the existing
transmission line corridor and will not require any additional easements.
The existing transmission lines are located in PSE’s Sammamish-Lakeside-Talbot
transmission line corridor, which was established in the late 1920s and early
1930s. Within the existing utility corridor, the proposed upgraded lines will place
poles in generally the same locations as existing poles. In some instances, poles
will be moved to accommodate landowner preferences and easement
considerations, and to minimize impacts to critical areas. During construction,
selective tree removal will occur within the corridor to meet federal vegetation
management requirements and PSE standards (see Section 3.3.4 for more
information).
The purpose of this Critical Areas Report is to document the exempt-status of
Project activities relative to specific critical areas, document critical area impacts,
and outline how the Project proposes to compensate for those impacts.
PSE Energize Eastside Project
Renton Critical Areas Report
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Figure 1. Map of Energize Eastside Project route in Renton and limits of the Critical Area
Impact Assessment.
3 M ETHODS
A Critical Areas Impact Assessment (“CAIA”) was conducted for the Project in
Renton. The analysis combined GIS-based assessment with field-verified
conditions and evaluated proposed project elements in relation to existing land
cover types and regulated critical areas. The location and type of each proposed
activity was used to determine impacts and inform the Mitigation Plan and is
based upon preliminary site plans provided by PSE (on 6/30/17 with updates
through 11/06/17). A detailed description of the CAIA process and methods is
provided in Appendix D.
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Revised January 2019
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3.1 Study Area
For the purposes of this report the study area is limited to a segment of the
proposed Energize Eastside corridor within Renton. The Renton corridor runs
from the north Renton city limits south of SE 95th Way to the existing Talbot Hill
substation in the vicinity of Beacon Way S, a distance of approximately 4 miles.
The study area in Renton is limited to the area within the boundaries of an
approximately 100-foot wide regional utility corridor, except between the Talbot
Hill substation and Shadow Hawk neighborhood where the study area was
widened to capture additional area based on refined design parameters. The
study area is depicted by the red line on the attached maps (Appendix A).
3.2 Data Compilation
Critical areas evaluated as a part of the analysis include wetlands, streams and
lakes, habitat conservation areas, flood hazard areas, geologic hazard areas
(including steep slopes, landslide hazards, erosion hazards, seismic hazards, and
coal mine hazards, wellhead protection areas, shorelines, and any associated
critical area buffers. To facilitate the CAIA, the following data were compiled
and reviewed: tree inventory, wetland and stream surveys, and publically
available data.
Tree Inventory
Existing trees with the potential to reach a height greater than 15 feet located in
the Project area corridor were inventoried between March and November 2015
and September and October of 2017. Tree inventory methodology and results are
available in the City of Renton Tree Inventory Report: Puget Sound Energy – Energize
Eastside Project (The Watershed Company 2016b). Tree data used in this CAIA
were obtained and compiled from surveys, GPS, and digitization using high-
resolution imagery.
Wetland and Stream Surveys
Wetlands and streams were originally delineated and classified within a defined
study area which generally consisted of a 100-foot wide corridor defined by an
established PSE easement, between March and October 2015. This delineation is
documented in the City of Renton Critical Areas Delineation Report: Puget Sound
Energy – Energize Eastside Project (The Watershed Company 2016a) included as
Appendix B. As the Project design became more refined, the need for additional
delineation was identified in the vicinity of the Cedar River and south of the
original study area corridor between the Talbot Hill substation and Shadow
Hawk neighborhood. These areas were delineated between September and
October of 2017 and are documented in PSE Energize Eastside-2017 Additional
Wetland and Stream Delineation in Renton (The Watershed Company 2017)
included as Appendix C of this report. Wetland and stream data were compiled
from field generated GPS data and are limited to the study areas defined in the
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delineation documentation. Delineation study methodology is detailed in the
previously-referenced reports.
Publicly Available Data
Publicly available Renton GIS data were utilized for mapping the following
critical areas in Renton: landslide hazard areas, erosion hazard areas, steep slope
hazard areas, coal mine hazard areas, seismic hazard areas, and flood hazard
areas.
Data used to map impervious surfaces and development include the King
County Impervious and Impacted Surface data (King County 2009),
supplemented with land survey data and high-resolution aerial photography
provided by PSE.
Additional detail about the data inventory elements and methodology are
available in Appendix D.
3.3 Project Element Construction – Potential Impacts
Project elements that have the potential to impact critical areas are defined in this
section and include the following:
- Pole replacement:
o removal of old poles
o installation of new poles
pole buffer (6-foot radius outside of pole footprint),
pole construction work area (varies by pole type, see
description below);
- Access routes (approximately 20 feet wide);
- Stringing sites; and
- Vegetation management requirements.
Pole Replacement
Existing H-frames (consisting of 2 or 3 poles) will be replaced with new
monopoles (i.e., a single pole). Existing pole sizes have been presumed to be
approximately 2.75 feet in diameter on average. The diameter of new poles
ranges from 3-6 feet. In general, relocation activities will occur in close proximity
to the existing H-frames, but some of the replacement poles will be moved to
accommodate landowner preferences, due to easement considerations, and to
minimize impacts to critical areas. To conduct this work, PSE created
construction scenarios specific to the type of structure being installed. Table 1
below describes the scenarios applicable to the Project. These scenarios provide
assumptions used to assess impacts.
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Revised January 2019
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Table 1. PSE construction scenarios.
Description Scenario
No Critical or Recreation Area Present
Direct embed-single pole
Temporary work area is generally 2,500 square feet
Create hole (hole will be larger than diameter of the new
pole)
New pole and backfill delivered to site
Place pole in hole and backfill annulus
Stabilize site
A A1
Foundation-single pole
Temporary work area is generally 5,000 square feet
Create hole (hole will be slightly larger to accommodate
foundation installation)
New pole and foundation materials delivered to site
Build foundation and install pole
Stabilize site
C C1
Critical or Recreation Area Present
Direct embed-single pole
Establish construction buffer from critical area using
appropriate BMPs
Temporary work area is generally 2,500 square feet
Create hole (hole will be larger than diameter of the new
pole)
New pole and backfill delivered to site
Place pole in hole and backfill annulus
Stabilize site
A A2
Foundation-single pole
Establish construction buffer from critical area using
appropriate BMPs
Temporary work area is generally 5,000 square feet
Create hole (hole will be slightly larger to accommodate
foundation installation)
New pole and foundation materials delivered to site
Build foundation and install pole
Stabilize site
C C2
While the work area for each pole type is defined as a consistent size to be
conservative, the shape of the disturbed area will vary depending on the
presence of critical areas or other sensitive features in the Project corridor.
During construction, critical areas and other sensitive features will be excluded
from the disturbance area where possible. Pole replacement will potentially
result in three types of impacts: permanent, vegetation conversion, and
temporary.
PSE Energize Eastside Project
Renton Critical Areas Report
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Permanent impacts will be associated with the installation of new poles,
which will have a base diameter ranging from 3 feet to 6 feet depending
on the pole type (direct imbed, or new foundation which has a larger base
diameter). However, some existing poles (which currently contribute to
permanent fill) will be removed from critical areas and this was taken
into account for wetland and stream buffer impact calculations.
Vegetation conversion impacts will be associated with the removal of
incompatible transmission line vegetation. The transmission line corridor,
experiences routine vegetation management which will continue. All
vegetation in the wire zone and managed right-of-way (ROW) portions of
the transmission line corridor, when mature, will be fifteen feet or less
(unless the topography allows for at least a 20-foot clearance between
vegetation and the lines). During typical inspections and maintenance of
the poles, vegetation is routinely disturbed; as such, no trees of any size
will grow within 6 feet of the new poles.
Where pole construction work areas and pole buffer areas do not require
the removal of trees, the resulting impacts will be temporary. The
majority of pole construction work area and pole buffer impacts are
expected to be temporary due to the existing use and management of the
corridor (i.e., lack of trees) and consideration that existing groundcover
will be restored or regenerate on its own within one growing season.
After construction, the temporarily disturbed areas will be re-vegetated
and left to return their natural state or enhanced.
BMPs will be used to minimize impacts resulting from pole replacement
activities. In critical areas or buffers, mats will be placed over existing vegetation
where possible. Typically, crushed vegetation rebounds within one growing
season resulting in only temporary impacts to vegetation. Post-construction, all
disturbed areas will be re-vegetated, if necessary, and left to return to their
natural state.
The impacts are further analyzed and quantified in Section 7 of this report.
Access routes
Access to pole removal and construction sites in critical areas will generally
occur using existing, partially vegetated access (established during original
construction and re-used over time to maintain the corridor). BMPs will be used
to minimize ground disturbance in these areas, and in new areas of access. In
critical areas or buffers, mats will be placed over existing vegetation where
possible. Typically, crushed vegetation rebounds within one growing season
resulting in only temporary impacts to vegetation. Where access route alignment
requires tree removal, impacts will be characterized as conversion. Post-
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construction, all disturbed areas will be re-vegetated, if necessary, and left to
return to their natural state in compliance with vegetation management
requirements. Based on the existing conditions, proposed construction BMPs,
and post-construction methods, disturbance associated with access in the
transmission corridor will predominantly be temporary.
Stringing Sites
In order to replace the transmission conductor, stringing and tensioning
equipment will be staged near new steel poles at specific locations along the
corridor in preparation for the stringing of new wire. The disturbance area
associated with the equipment and materials to restring the conductor wire will
be outside of wetlands and streams. In other critical areas and buffers, mats will
be placed over existing vegetation where possible to allow access to poles for
stringing activities. Typically, crushed vegetation rebounds within one growing
season resulting in only temporary impacts to vegetation. Tree removal activities
necessary for the stringing of new wire (in the wire zone) will be performed in a
manner to minimize impacts to underlying shrubs, groundcover and other trees,
and with minimal disturbance to soil. Various techniques will be utilized to
string the wire to minimize surface disturbance (i.e., shooting the wire past
obstacles, pulling it along established guide wire, helicopter, etc.).
For this analysis, stringing sites have been identified as point locations and not
polygons (Appendix A). However, each stringing site will cause approximately
7,500 square feet of disturbance. Similar to pole construction work areas, the
shape of the stringing site will depend upon the presence of adjacent critical
areas, existing land conditions, and area needed for equipment staging based on
the necessary angle needed to string the conductor. In many areas, this
disturbance will overlap with various impacts quantified for proposed access,
pole installation, and vegetation management. While impacts have not been
quantified for stringing sites, stringing sites are expected to largely overlap other
work areas and are not expected to require additional tree removal. Any
additional impacts resulting from stringing sites, not already quantified in
Section 7 through other Project elements, will be temporary in nature. Stringing
sites will not result in permanent impacts to critical areas. Temporary impact
areas will also be avoided to the extent feasible. Unavoidable temporary impact
areas will be re-vegetated and left to return to their natural state or enhanced
following construction.
Vegetation Management
Vegetation in the existing corridor is routinely managed. The corridor was
initially disturbed during original construction (including soil compaction
associated with construction activities for the line itself and roads, parking lots,
subdivisions, trails, and commercial development). Disturbance is regular and
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Renton Critical Areas Report
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ongoing due to maintenance and pole replacement activities. With the exception
of the Cedar River and Honey Creek areas, the majority of trees in the existing
corridor are ornamental and associated with existing residential or commercial
property uses.
Vegetation in a transmission line corridor that has an operational voltage of more
than 200 kV must be managed in compliance with federal requirements.
Vegetation management standards vary depending upon the location of
vegetation management in relation to transmission wires. These specific locations
are defined as follows:
Wire Zone – Section of a utility transmission ROW extending to 10 feet
from the outside transmission wire(s). Vegetation with a mature height of
15 feet or less is allowed in this zone.
Managed ROW – The section of a transmission line ROW that extends 6
feet outside of the wire zone. Vegetation with a mature height of 15 feet
or less is allowed in this zone.
Legal ROW – The full width of the easement. While vegetation
maintenance is permitted within the full extent of the legal ROW, based
on communication with PSE, only a portion of the legal ROW is intended
to be maintained; this area is described as the maintained legal ROW and
generally extends 10 feet from the edge of the managed ROW. Maximum
height of mature vegetation between the managed ROW and legal ROW
is dependent upon tree species, tree health, and distance from the wires.
Consistent with federal standards, vegetation in the wire zone must have a
mature height of no greater than 15 feet, unless the topographic change is
sufficient to allow a 20-foot vertical clearance between the power lines and the
mature height of trees under the power lines. The same vegetation requirement
was applied to the managed ROW zone. The legal ROW is composed of existing
and proposed easements; its width is approximately 100 feet through Renton.
The area outside of the managed ROW, but still within the legal ROW, is also
subject to select clearing of trees that pose a risk of damaging the lines. To
facilitate the CAIA, in the maintained legal ROW, a maximum mature tree height
of 70 feet was presumed. However, existing trees greater than 70 feet, or with a
mature height of greater than 70 feet will not necessarily be removed.
Accordingly, the CAIA conservatively estimates the number of trees that will be
removed. Impacts resulting from required vegetation management are
characterized as conversion in Section 7 of this report.
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3.4 Critical Areas Impact Analysis
The CAIA was conducted by placing tree points/polygons and critical area
polygons on a georeferenced base map and overlaying preliminary site plans to
determine impacts. Impervious surfaces and other similar areas characterized as
developed were removed from wetland and stream buffer areas for this CAIA as
non-functioning buffer areas. The resulting functioning wetland and stream
buffers are shown in Appendix A.
Where Project elements (as discussed in Section 3.3) are located in critical areas
or their functioning buffers, impacts are quantified based on area (square footage
[SF] of impact). Impact results were generated based upon the expected long-
term condition of the area compared to the existing condition and include
permanent impacts, impacts that result in vegetation conversion, temporary
impacts, and activities that result in no change or no impact (see Section 7). For
more detailed methodology on the CAIA, refer to Appendix D.
Impacts associated with new or replaced Lake Tradition Line poles were
analyzed differently than the rest of the Project elements as the adjustments
made to the Lake Tradition line to accommodate the Project entail different
elements and impacts than the actions associated with the Project. Work
associated with the Lake Tradition line is restricted to one area of the project
corridor, affecting approximately five adjacent spans. Work includes resetting
existing poles, adding new poles, and rehanging lines on existing poles. Due to
the limited work and the utilization of existing poles, no vegetation impacts
resulting from conflicts between wire height and tree height are anticipated.
Therefore, for new or replaced poles along the Lake Tradition line, tree removal
impacts were calculated based solely on proximity to proposed pole work areas.
The long-term condition and impact characterization for “pole work area” was
consistent with the parameters of the Energize Eastside analysis, as described in
Appendix D.
3.5 Limitations
The Watershed Company’s technical expertise is specific to wetlands, streams,
habitat conservation areas, and shorelines. The geotechnical assessments and
interpretation of impacts within geologic hazard areas have been addressed by
others and referenced in the report and incorporated as Appendix E.
This document represents a point-in-time analysis of the proposed Project,
critical area and buffer impacts, and an approach to mitigation. Refinements
made as a result of ongoing design are expected to decrease Project impacts to
critical areas and critical area buffers moving forward.
PSE Energize Eastside Project
Renton Critical Areas Report
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4 E XISTING C ONDITIONS
4.1 Site Location
The Renton study area is dominated by urban land uses. The majority of the
corridor is zoned residential, commercial, or industrial. Within the residential
areas, the corridor passes through several distinct neighborhoods; from north to
south, these include Glencoe, Honey Creek Ridge, Sunset, Liberty Ridge, and
Shadow Hawk. The largest patch of remaining undeveloped land is located
adjacent to the Cedar River and zoned Resource Conservation (RC).
The study area corridor is primarily located in the Cedar-Sammamish Watershed
(WRIA 8). Within WRIA 8 the Project area lies within three drainage basins. The
north end of the study area is within the May Creek basin, the middle portion is
within the East Lake Washington basin, and the southern portion is in the Lower
Cedar River drainage basin. No wetlands or streams were identified in the East
Lake Washington basin. At the southern end of the corridor, near the Talbot Hill
substation, the study area drains into the Black River basin of the Duwamish-
Green Watershed (WRIA 9). The study area corridor in the Renton is located in
Township 23N, Range 05E, and Sections 4, 9, 16, 20, and 21.
4.2 Site Description
When the corridor was constructed in the late 1920s and early 1930s, the entire
corridor was cleared. Construction activities resulted in a compacted subsurface
in those areas where the poles were installed. Since that time, the corridor has
been continually maintained by PSE through easement rights. Using existing
access routes/paths, poles have been replaced and vegetation has been managed.
To do so, vehicles and equipment (such as cranes) have been used in the
corridor. Over time, development has occurred adjacent to and within the
corridor, including residential development, roads, parking lots, commercial
development, and the establishment of trails (using overgrown access routes).
The Talbot Hill area is utilized by an extensive number of co-located critical
utilities. PSE owns and operates the Talbot Hill substation located on parcel
#2023059003 into which nine existing 115 kV transmission lines connect, as well
as the existing PSE-owned Talbot Hill–Berrydale #3 230 kV transmission line.
Two of the 115 kV transmission lines will be upgraded to 230 kV as part of the
Project. Bonneville Power Administration (BPA) owns and operates the BPA
Maple Valley substation located immediately east of the Talbot Hill substation
on adjacent parcel #023059062 into which one PSE-owned 230 kV, two BPA-
owned 230 kV, and two BPA-owned 500 kV lines connect. Two 230 kV lines
connect the Talbot Hill substation to the BPA Maple Valley substation. Seattle
City Light (SCL) owns and operates two 230 kV transmission lines in the area,
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Revised January 2019
13
one of which connects to the Talbot Hill substation and the other to the BPA
Maple Valley substation. Between the two substations on parcel #2023059051,
Seattle Public Utilities (SPU) owns and operates three large watermains that
transport the primary water supply from the Cedar River Watershed to the City
of Seattle. The 20-inch-diameter Olympic Pipeline (OPL) traverses west to east
within several easements north of the PSE and BPA substations within the
transmission line corridor utilized by PSE, BPA, and SCL. Within this utility
corridor, PSE and BPA also operate dedicated fiber optic lines that are attached
to the existing transmission line pole structures.
In general, vegetation management requirements of pipelines are more
restrictive than the vegetation management requirements for the transmission
line described herein. For example, trees and shrubs are expected to be mowed
or removed on a more regular basis than for the transmission lines to prevent
damage to the pipeline by large roots. In addition, a corridor of herbaceous
vegetation may be maintained both to keep the area free of large tree and shrub
roots and to be able to easily, visually inspect the pipeline corridor from the
ground and/or air. As noted above, the OPL traverses west to east within several
easements north of the PSE and BPA substations at the southern end of the
project area, and again is within the Project transmission line easement in the
northern end of the Project area where the Renton City limits intersect with
unincorporated King County. This, and other co-located utilities act as a regular,
contributing source of ongoing vegetation maintenance in the shared corridor.
Most of the study area corridor in Renton has been developed. Vegetation in
residential, commercial, and industrial areas can be generally described as
maintained yards or landscaped. On parcels that have not been developed as
commercial or residential property, vegetated areas are often dominated by
invasive plants including Himalayan blackberry and reed canarygrass. Forested
patches are limited to topographically low regions near the Cedar River and
Honey Dew Creek.
4.3 Critical Areas
This section defines Renton-regulated critical areas per Section 4-3-050 (Critical
Areas Regulations) of the RMC and describes the general location(s) of each
critical area type in the proposed Project corridor. Regulated critical areas
include wetlands, streams, habitat conservation areas, flood hazard areas,
geologic hazard areas (i.e., steep slopes, landslide hazards, erosion hazards,
seismic hazards, and coal mine hazards), and wellhead protection areas.
Wetlands
Renton defines wetlands as follows (RMC 4-11-230):
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Areas that are inundated or saturated by surface water or groundwater 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. Wetlands generally include swamps, marshes, bogs,
and similar areas. Wetlands do not include those artificial wetlands intentionally
created from nonwetland sites, including, but not limited to, irrigation and
drainage ditches, grass-lined swales, canals, detention facilities, wastewater
treatment facilities, farm ponds, and landscape amenities, or those wetlands
created after July 1, 1990, that were unintentionally created as a result of the
construction of a road, street, or highway. Wetlands include artificial wetlands
created from nonwetland areas to mitigate the conversion of wetlands.
Seven wetlands were identified in the vicinity of the proposed Project corridor in
Renton. They are generally located near the Cedar River and south, between SE
Cedar Ridge Drive and the Shadow Hawk neighborhood. Wetlands will not be
directly impacted as a result of the Project (Section 7). See Section 5.1.1 for further
description of identified wetlands and Appendix A for wetland locations.
Streams and Lakes
Renton defines streams and lakes by class in RMC 4-3-050.G.7 as follows:
Type S: Waters inventoried as “Shorelines of the State” under chapter 90.58
RCW. These waters are regulated under Renton’s Shoreline Master Program
Regulations, RMC 4-3-090.
Type F: Waters that are known to be used by fish or meet the physical criteria to
be potentially used by fish and that have perennial (year-round) or seasonal
flows.
Type Np: Waters that do not contain fish or fish habitat and that have perennial
(year-round) flows. Perennial stream waters do not go dry any time of a 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.
Type Ns: Waters that do not contain fish or fish habitat and have intermittent
flows. 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.
Under this section, non-regulated features include:
…irrigation ditches, grass-lined swales and canals that do not meet the criteria
for Type S, F, Np, or Ns Non-regulated waters may also include streams created
as mitigation. Purposeful creation must be demonstrated through
documentation, photographs, statements and/or other persuasive evidence.
A total of four streams are located along the proposed Project corridor in Renton.
Stream MR01 (Honey Dew Creek) is located on the north side of Renton, north of
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SR-900, and is a tributary to May Creek. The corridor crosses the Cedar River
located further to the south, near the Maple Valley Highway. Streams NR01
(Ginger Creek) and NR02 are tributaries to the Cedar River, located between the
Talbot Hill substation at the corridor’s southern extent and the Shadow Hawk
neighborhood. No lakes are present in the Project area. See Section 5.1.1 for detail
of stream types.
Streams will not be directly impacted as a result of the Project (Section 7).
Habitat Conservation Areas
Renton provides two classifications or definitions related to regulated habitat
areas that vary slightly. The following are a “classification of critical habitats”
from RMC 4-3-050.G.6 and definition of “critical habitat” from RMC 4-11-030,
respectively:
Classification of Critical Habitats: Habitats that have a primary association with
the documented presence of non-salmonid or salmonid species (see subsection
L1 of this Section and RMC 4-3-090, Shoreline Master Program Regulations, for
salmonid species) species proposed or listed by the Federal government or State
of Washington as endangered, threatened, sensitive and/or of local importance.
Critical Habitat or Critical Wildlife Habitat: Habitat areas associated with
threatened, endangered, sensitive, monitored, or priority species of plants or
wildlife and which, if altered, could reduce the likelihood that the species would
maintain and reproduce over the long term.
Available Habitat
The Project area is located in an urban and developed landscape. While the
power line corridor is vegetated, vegetation predominantly consists of low-
growing grasses, landscape plants and invasive plant species typical of
maintained utility corridor areas. The corridor generally offers little in terms of
habitat value when compared to other natural urban parks and greenspaces,
which are expected to provide more vegetative cover, structure, and diversity,
and fewer invasive plant species. Two forested patches are present in the Project
area that are considered to have an increased potential for wildlife use (when
compared to other Project areas in Renton); these include the forested ravines
associated with Honey Dew Creek and the Cedar River. Even at these locations,
original construction of transmission lines, existing and ongoing vegetation
maintenance activities associated with the corridor, and the surrounding urban
landscape setting reduce the likelihood that regulated species will utilize power
line corridor areas for breeding.
WDFW’s online mapping program, Priority Habitat and Species (PHS) on the
Web, was reviewed for known priority habitats in the Project area. Two
Biodiversity Areas and Corridors are mapped on forested slopes north and south
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of the Cedar River, respectively. North of this area, two small freshwater pond
polygons are also shown. The areas located at and in the vicinity of the
freshwater pond polygons were screened during the original delineation study;
no ponds or wetlands are located in the vicinity of these mapped features.
The environmental designation of the shoreline zone on the south side of the
Cedar River is Urban Conservancy, qualifying this area as a Class 1 Fish and
Habitat Conservation Area per RMC 4-3-090.D.2.c.iii.
Federally-listed Species
Endangered Species Act (ESA) documentation for the south segment of the
Project, which includes the South Bellevue Segment, Newcastle, and Renton was
submitted to the U.S. Army Corps of Engineers (Biological Evaluation- Puget
Sound Energy Energize Eastside Project, The Watershed Company September
2018) and addresses the potential for the project to impact federally-listed
species. As summarized in that document, the proposed Project will may effect
but is unlikely to adversely effect ESA-listed species based upon lack of
documented use, lack of suitable habitat, and/or avoidance during the project’s
limited in-water work.
State-listed Species
State-listed species, that are not also listed as federally threatened or endangered
(i.e., covered in the ESA document) are provided in Table 2. Of the species listed
in Table 2, none are expected to occur in the Project area; use of the corridor is
precluded by absence of suitable habitat and/or the species’ known distribution
and range in Washington State.
Table 2. State-listed wildlife species, excluding those listed as federally endangered and
threatened.
Wildlife
Type Common Name Scientific Name
Listing
Status1
State Federal
Mammals fisher Martes pennanti SE FSC
- Habitat/Distribution: Historic range includes western Washington lowlands.
Current range is fragmented in Washington (and is from the species
reintroduction in national parks) and more extensive in Canada. Preferred
habitat is closed-canopy forests.
- Determination: Distribution does not overlap Project area.
gray whale Eschrichtius robustus SS --
- Habitat/Distribution: Marine.
- Determination: Habitat not present in Project area.
Mazama pocket gopher Thomomys mazama ST FSC2
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Wildlife
Type Common Name Scientific Name
Listing
Status1
State Federal
- Habitat/Distribution: Distribution limited to prairie habitats in Pierce and
Thurston Counties.
- Determination: Distribution does not overlap Project area.
sea otter Enhydra lutris SE FSC
- Habitat/Distribution: Marine.
- Determination: Habitat not present in Project area.
Birds American white pelican Pelecanus erythrorhynchos ST --
- Habitat/Distribution: Breeding and non-breeding range is limited to central
and eastern Washington.
- Determination: Distribution does not overlap Project area.
common loon Gavia immer SS --
- Habitat/Distribution: Known to breed on secluded lakes in King County.
Commonly over winters in protected marine waters of Puget Sound.
- Determination: Habitat not present in Project area.
ferruginous hawk Buteo regalis ST --
- Habitat/Distribution: Steppe or shrub-steppe habitat of eastern
Washington Counties.
- Determination: Habitat and distribution does not overlap Project area.
greater sage-grouse Centrocercus urophasianus ST FSC
- Habitat/Distribution: Shrub-steppe habitats of central and eastern
Washington.
- Determination: Habitat and distribution does not overlap Project area.
sandhill crane Grus canadensis SE --
- Habitat/Distribution: No historic or current breeding sites in King County.
- Determination: Distribution does not overlap Project area.
Columbian sharp-tailed
grouse Tympanuchus phasianellus ST --
- Habitat/Distribution: Historical range is non-forested areas east of
Cascades; current range is much smaller and fragmented in eastern
Washington.
- Determination: Distribution does not overlap Project area.
tufted puffin Fratercula cirrhata SE --
- Habitat/Distribution: Coastal waters of Washington.
- Determination: Distribution does not overlap Project area.
upland sandpiper Bartramia longicauda SE --
- Habitat/Distribution: Scattered historical breeding records for eastern
Washington; may now be extirpated.
- Determination: Distribution does not overlap Project area.
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Wildlife
Type Common Name Scientific Name
Listing
Status1
State Federal
Reptiles
and
Amphibians
Western pond turtle Actinemys marmorata SE --
- Habitat/Distribution: Historical distribution likely included western King
County; however, no current populations are known in this area. In
Washington, the species was essentially extirpated by the 1980s. Important
aquatic habitat features include underwater refugia, still/slow water, and
basking structures.
- Determination: Suitable aquatic habitat may be available in permanently
ponded areas of Wetland NR02 and Wetland NR03. However, the local
distribution and populations (only three known, none of which are in King
County) of this species have been well studied and indicate that western
pond turtles are not likely to occur in the Project area.
Larch Mountain
salamander Plethodon larselli SS --
- Habitat/Distribution: Populations generally limited to southern Washington
counties near the Columbia River Gorge.
- Determination: Distribution does not overlap Project area.
Northern leopard frog Lithobates pipiens SE --
- Habitat/Distribution: Current and historic distribution limited to eastern
Washington.
- Determination: Distribution does not overlap Project area.
Fishes pygmy whitefish Prosopium coulterii SS --
- Habitat/Distribution: Only known population in King County is in Chester
Morse Lake and associated portions of the Cedar and Rex Rivers (tributaries
for breeding); all populations in Washington are believed to have been
identified.
- Determination: Distribution does not overlap Project area.
margined sculpin Cottus marginatus SS --
- Habitat/Distribution: Confined to the Tucannon and Walla Walla drainages
in southeastern Washington.
- Determination: Distribution does not overlap Project area.
Olympic mudminnow Novumbra hubbsi SS --
- Habitat/Distribution: Known populations in southern and western lowlands
of the Olympic Peninsula, the Chehalis and lower Deschutes River
drainages, and south Puget Sound lowlands west of the Nisqually River.
Recent occurrences in King and Snohomish Counties are considered to be
outside of the species’ natural range.
- Determination: Project area is located outside of species’ natural range.
Insects Mardon skipper Polites mardon SE FSC
- Habitat/Distribution: Distribution in Puget Prairie (Pierce and Thurston
counties) and South Cascades (Klickitat and Yakima counties).
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Wildlife
Type Common Name Scientific Name
Listing
Status1
State Federal
- Determination: Distribution does not overlap Project area.
1 Listing Status Codes:
SE = State Endangered SS = State Sensitive
ST = State Threatened FSC = Federal Species of Concern
2 depending upon subspecies.
Priority Species
WDFW’s PHS data were also reviewed for the Project vicinity (PHS on the Web).
Salmonid fish use is mapped for the Cedar River and Honey Dew Creek and as
stated previously, Biodiversity Areas and Corridors are shown north and south
of the Cedar River. According to WDFW’s online databases (PHS on the Web
and SalmonScape), salmonid species known or modeled to occur in the Cedar
River are cutthroat trout, bull trout, steelhead, kokanee, sockeye salmon,
Chinook salmon, and coho salmon, thereby establishing the Cedar River as a
Habitat Conservation Area (HCA). Similarly, salmonids known or modeled to
occur in Honey Dew Creek include steelhead, Chinook salmon, coho salmon,
sockeye salmon, and cutthroat trout, thereby establishing Honey Dew Creek as a
HCA as well.
In addition to reviewing WDFW’s database (PHS on the Web) for known PHS
locations, the Priority Habitats and Species List (WDFW 2008) was reviewed in
conjunction with species’ known distribution, range, and habitat, to determine
the likelihood of priority species’ association with observed habitat in the Project
area. A list of 95 priority species for King County (WDFW 2013) were reviewed
for this assessment. The vast majority are not expected in the Project area, using
the same process outlined in Table 2, due to a lack of suitable habitat types or
special habitat features.
Priority species that have the greatest potential to utilize habitat in the corridor
are Columbian black-tailed deer, western toad, great blue heron, pileated
woodpecker, and cavity nesting ducks. These species can be relatively common
in urban settings, and are discussed below.
Columbian black-tailed deer (Odocoileus hemionus columbianus) are
Washington’s most common deer sub-species. They are relatively tolerant
of disturbance and occur in a variety of habitats from residential areas
and logged lands to coniferous forests. Their priority-species status is
based upon recreational, commercial, and/or tribal importance (WDFW
2008). Local populations and habitat areas are not considered to be in
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jeopardy. Columbian black-tailed deer are not dependent upon habitat in
the Project corridor. Furthermore, habitat in the corridor is not expected
to be significantly altered by the proposed transmission line upgrade.
Columbian black-tailed deer use of the corridor is expected post-Project
construction. Temporary construction activities have the potential to
affect the distribution of some individuals. Deer are expected to avoid
construction activities by moving to other habitat areas. There are no
areas in the corridor that are considered a HCA based upon association
with Columbian black-tailed deer at this time.
Western toad (Anaxyrus boreas) range spans much of Washington State
including western Washington and the greater Seattle area. The species
reportedly remains common throughout much of its range but has
experienced population declines. Western toad can be found in many
habitats including desert springs and streams, meadows, woodland,
mountain wetlands, and agricultural land (IUCN SSC Amphibian
Specialist Group 2015). Western toad habitat in the study area is generally
limited to aquatic and terrestrial habitats associated with the Cedar River
including Wetlands NR02 and NR03 that could be used for breeding (i.e.,
shallow slow-moving water). PHS on the Web (WDFW n.d.) documents
western toad occurrences in King County, but none are in the vicinity of
the Project area. No western toads were observed during field work
activities. Project activities will not significantly impact the habitat in the
Cedar River ravine, where western toad habitat is most suitable. There
are no areas in the corridor that are considered a HCA based upon
association with western toad at this time.
Great blue herons (Ardea Herodias) are large wading birds most often
found near water. Great blue herons forage in a variety of habitats near
streams, lakes, ponds, wetlands, saltwater shorelines, and upland fields.
They nest in colonies, typically in trees near foraging habitat. There are no
known great blue heron nest sites (i.e., rookeries) in close proximity to the
Project area (WDFW n.d.). One great blue heron was detected near the
Cedar River and Wetland NR02 during October 2017 field work activities.
The Cedar River and Wetland NR02 likely provide foraging habitat for
this species. If an active heron rookery is identified along the Project
corridor, a PSE avian biologist will develop and implement a strategy to
prevent impacts to the heron rookery during the nesting season in
coordination with WDFW. Project activities will not significantly alter the
habitat in the Cedar River ravine. There are no areas in the corridor that
are considered a HCA based upon association with great blue heron at
this time.
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Pileated woodpeckers (Dryocopus pileatus) most often nest in old-growth
forest and mature forest stands. However, they are increasingly found in
urban areas as long as there are large trees that can provide roosting and
nesting habitat. One pileated woodpecker was observed in the Honey
Dew Creek ravine during field work activities in 2015. The topographic
relief between the transmission lines and existing vegetation in the Honey
Dew Creek and Cedar River ravines has allowed for forests to become
established beneath the transmission lines at these locations. Outside of
these ravines, the Project area does not contain the appropriate vegetation
to support this species due to the vegetation management requirements
associated with the power lines; however, pileated woodpeckers have
been known to use utility poles for nesting. Pileated woodpeckers may
utilize the forested habitat of the Honey Dew Creek and Cedar River
ravines, as well as utility poles in the Project area, for some portion of
their life history.
If pileated woodpeckers are observed excavating poles, trees, or snags
within the Project area, PSE avian biologists will be consulted to
determine whether the pole, tree, or snag is being used for nesting or
foraging. If it is determined to be in use for foraging by pileated
woodpeckers, the Project will have minimal effects by potentially causing
temporary disturbance to foraging behavior. If pileated woodpecker nests
are found, depending on nest occupancy, a PSE avian biologist will
develop and implement a strategy to prevent impacts to the pileated
woodpeckers during the nesting season in coordination with WDFW
during construction and maintenance activities.
There are no areas in the corridor that are considered a HCA based upon
association with pileated woodpecker at this time. Even so,
recommended mitigation strategies and BMPs currently proposed
include the creation of habitat snags, retaining stumps, and placement of
large woody debris, consistent with WDFW’s general management
recommendations for this species (Lewis and Azerrad 2003).
Cavity nesting duck habitat consists of wetlands, riparian areas, lakes, or
beaver ponds that contain a forested canopy with abundant downed logs
and downed woody debris. Suitable cavity nesting duck habitat, namely
for hooded mergansers and wood ducks in western Washington, exists in
the study area in the vicinity of Wetlands NR02 and NR03 near the Cedar
River. Project impacts in this area occur entirely outside of the
jurisdictional shoreline and will not negatively alter the habitat in the
Cedar River ravine; new transmission lines will span the ravine and
construction activities will not occur at the bottom of the ravine. While no
cavity nesting ducks are known to be present in the Project area currently,
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if they are present, they could be disturbed by increased noise but would
be expected to continue use of the area after construction work is
complete. There are no areas in the corridor that are considered a HCA
based upon association with cavity nesting ducks at this time.
Other priority species that are less likely to use habitat available in the Project
corridor, but may be present particularly while traveling or foraging include
Townsend’s big-eared bat (Corynorhinus townsendii), Vaux’s swift (Chaetura
vauxi), and band-tailed pigeon (Patagioenas fasciata). However, these species are
not closely associated with habitat found in the existing transmission line
corridor. Any disturbance from Project-related activities would be temporary
and would not impede the foraging of nearby habitats.
Species of Local Importance
Renton does not currently maintain or regulate a list of species of local
importance.
HCA Summary
To summarize, the south side of the Cedar River within shoreline jurisdiction is
considered a Class 1 Fish Habitat Conservation Area; and the Cedar River and
Honey Dew Creek are considered Habitat Conservation Areas. The associated
stream buffers and critical area regulations for streams are expected to
adequately protect the Cedar River and Honey Dew Creek habitat areas for the
duration of the Project.
Two PHS-mapped Biodiversity Areas and Corridor polygons are present in the
Project corridor. When considered as a whole, habitats of wildlife species
regulated under RMC 4-3-050.G.6 (like pileated woodpecker) are presumed to
have a primary association with these large swaths of forest. Therefore, the PHS
Biodiversity Areas and Corridor polygons are also considered HCAs.
While Columbian black-tailed deer, western toad, pileated woodpecker, and
cavity nesting ducks could be expected to utilize habitat in the Project corridor,
proposed activities are not expected to significantly affect the use of the corridor
by these species. At this time no additional HCAs related to these species are
considered to be present in the Project area.
In addition, PSE implements an Avian Protection Plan to protect avian wildlife
from harmful interactions with their utility equipment. The Plan includes
preventing the creation of potentially harmful nests and monitoring known nest
sites when construction activities occur in close proximity during the nesting
season (Puget Sound Energy n.d.). Potential Project impacts to birds that could
be expected to utilize habitat in the Project area are mitigated through the PSE’s
bird protection programs and procedures.
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Flood Hazard Areas
The City of Renton defines Flood Hazard Areas in RMC 4-3-050.G.4 as follows:
Flood hazard areas are defined as the land in the floodplain subject to one
percent (1%) or greater chance of flooding in any given year. Designation on
flood maps always includes the letters A or V.
Flood hazard areas are mapped along the Cedar River in the corridor. Flood
hazard areas include both the 100-year floodplain and floodway. As Project
activities are not proposed within flood hazard areas, impacts will not occur.
Geologic Hazard Areas
Geologic hazard areas are regulated as critical areas per RMC 4-3-050.G.5.
Geologically hazardous areas include steep slopes, landslide hazards, erosion
hazard, seismic hazards, and coal mine hazards as defined below.
a. Steep Slope Types:
i. Sensitive Slopes: A hillside, or portion thereof, characterized by: (a) an
average slope of twenty five percent (25%) to less than forty percent
(40%) as identified in the City of Renton Steep Slope Atlas or in a method
approved by the City; or (b) an average slope of forty percent (40%) or
greater with a vertical rise of less than fifteen feet (15') as identified in
the City of Renton Steep Slope Atlas or in a method approved by the City;
(c) abutting an average slope of twenty five percent (25%) to forty
percent (40%) as identified in the City of Renton Steep Slope Atlas or in a
method approved by the City. This definition excludes engineered
retaining walls.
ii. Protected Slopes: A hillside, or portion thereof, characterized by an
average slope of forty percent (40%) or greater grade and having a
minimum vertical rise of fifteen feet (15') as identified in the City of
Renton Steep Slope Atlas or in a method approved by the City.
b. Landslide Hazards:
i. Low Landslide Hazard (LL): Areas with slopes less than fifteen percent
(15%).
ii. Medium Landslide Hazard (LM): Areas with slopes between fifteen
percent (15%) and forty percent (40%) and underlain by soils that consist
largely of sand, gravel or glacial till.
iii. High Landslide Hazards (LH): Areas with slopes greater than forty
percent (40%), and areas with slopes between fifteen percent (15%) and
forty percent (40%) and underlain by soils consisting largely of silt and
clay.
iv. Very High Landslide Hazards (LV): Areas of known mapped or
identified landslide deposits.
c. Erosion Hazards:
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i. Low Erosion Hazard (EL): Areas with soils characterized by the Natural
Resource Conservation Service (formerly U.S. Soil Conservation Service)
as having slight or moderate erosion potential, and a slope less than
fifteen percent (15%).
ii. High Erosion Hazard (EH): Areas with soils characterized by the
Natural Resource Conservation Service (formerly U.S. Soil Conservation
Service) as having severe or very severe erosion potential, and a slope
more than fifteen percent (15%).
d. Seismic Hazards:
i. Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock.
These soils generally have site classifications of A through D, as defined
in the International Building Code, 2012.
ii. High Seismic Hazard (SH): Areas underlain by soft or loose, saturated
soils. These soils generally have site classifications E or F, as defined in
the International Building Code, 2012.
e. Coal Mine Hazards:
i. Low Coal Mine Hazards (CL): Areas with no known mine workings and
no predicted subsidence. While no mines are known in these areas,
undocumented mining is known to have occurred.
ii. Medium Coal Mine Hazards (CM): Areas where mine workings are
deeper than two hundred feet (200') for steeply dipping seams, or
deeper than fifteen (15) times the thickness of the seam or workings for
gently dipping seams. These areas may be affected by subsidence.
iii. High Coal Mine Hazard (CH): Areas with abandoned and improperly
sealed mine openings and areas underlain by mine workings shallower
than two hundred feet (200') in depth for steeply dipping seams, or
shallower than fifteen (15) times the thickness of the seam or workings
for gently dipping seams. These areas may be affected by collapse or
other subsidence.
All geologic hazard area types are present in the study area. They have been
reviewed and summarized in a report by GeoEngineers (Appendix E), the
findings of which have been incorporated into this report where appropriate.
According to GeoEngineers, mapped sensitive and protected steep slopes and
moderate or unclassified landslide hazard areas are present within the Project
area, however many of these areas are developed and include rockeries,
landscaped residential or commercial development slopes and cut slopes
associated with paved roadways. GeoEngineers states that the following areas
(described in terms of proposed activity) are unlikely to be adversely impacted
by the Project and are excluded from their detailed analysis:
One tree removed in the mapped corridor east of North 23rd Court;
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Multiple trees removed east of the residence at 2101 Newport Court NE;
One tree removed east of the residence at 23118 NE 18th Street;
One tree removed on the east side of the Goodwill parking lot at 3208 NE
Sunset Boulevard;
Multiple trees removed on the east side of an existing parking lot for 3244
NE 12th Street;
Multiple trees removed on the east side of existing residence from 1082 to
1074 Lynwood Avenue NE;
One tree removed on the campus of the Renton Technical College; and
One tree removed west of the apartment complex at SE 8th Street and
Harrington Place SE.
Localized natural areas of sensitive and protected steep slopes and moderate or
unclassified landslide hazard areas in the Project area include the Honey Dew
Creek drainage and the Cedar River drainage, which include slopes greater than
40 percent with a 15-foot vertical elevation rise. GeoEngineers focused their
analysis on these areas. For the purposes of the impact analysis, these areas are
referred to as priority steep slope and priority landslides hazard areas and are
shown in the attached critical area maps (Appendix A). A detailed discussion of
proposed Project impacts to geologic hazard areas is provided in Section 7 of this
report.
Erosion hazards are located on slopes north and south of the Cedar River and
Honey Dew Creek.
The only mapped seismic hazard area in the study area is associated with the
Cedar River and lands immediately adjacent to the river.
Coal mine hazards are mapped from the southern end of the study area,
including the Talbot Hill Substation, to the Shadow Hawk neighborhood.
Wellhead Protection Areas
Renton defines Wellhead Protection Areas in RMC 4-3-050.A.8 as follows:
…the portion of an aquifer within the zone of capture and recharge area for a
well or well field owned or operated by the City.
The following Wellhead Protection Area Zones may be designated:
(a) Zone 1: The land area situated between a well or well field owned by the City
and the three hundred sixty five (365) day groundwater travel time contour.
(b) Zone 1 Modified: The same land area described for Zone 1 but for the
purpose of protecting a high-priority well, wellfield, or spring withdrawing from
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a confined aquifer with partial leakage in the overlying or underlying confining
layers. Uses, activities, and facilities located in this area are regulated as if
located within Zone 1 except as provided by this subsection G8.
(c) Zone 2: The land area situated between the three hundred sixty five (365) day
groundwater travel time contour and the boundary of the zone of potential
capture for a well or well field owned or operated by the City. If the aquifer
supplying water to such a well, well field, or spring is naturally protected by
confining overlying and underlying geologic layers, the City may choose not to
subdivide a Wellhead Protection Area into two (2) zones. In such a case, the
entire Wellhead Protection Area will be designated as Zone 2.
The study area spans wellhead protection areas mapped as Zone 1 and Zone 2.
Zone 1 encompasses the Cedar River. Zone 2 surrounds Zone 1, excludes the
Talbot Hill Substation, and extends north. They have been reviewed and
summarized in a report by GeoEngineers (Appendix E), the findings of which
have been incorporated into this report where appropriate. As with their analysis
of proposed actions within geologic hazard areas, GeoEngineers’ review focuses
on the Honey Dew Creek and Cedar River drainage areas. Project actions are not
expected to impact wellhead protection areas in these drainage areas.
4.4 Shorelines of the State
The Cedar River is the only Shoreline of the State present in the Project area.
Shorelines of the State and critical areas located in shoreline jurisdiction are
regulated under RMC 4-3-090 (Shoreline Master Program [SMP] Regulations)
and are defined as follows:
The Renton Shoreline Master Program applies to Shorelines of the State, which
include Shorelines of Statewide Significance and shorelines as defined in chapter
4-11 RMC and as listed below.
1. Shorelines of Statewide Significance:
a. Lake Washington;
b. Green River (the area within the OHWM of the Green River is not
within the Renton City Limits, but portions of the two hundred foot
(200') shoreline jurisdiction are within City limits).
2. Shorelines:
a. Cedar River;
b. May Creek from the intersection of May Creek and NE 31st Street in
the southeast quarter of the southeast quarter of Section 32-24-5E WM;
c. Black River;
d. Springbrook Creek from the Black River on the north to SW 43rd Street
on the south;
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e. Lake Desire (in the City’s potential annexation area at the time of
adoption of the Shoreline Master Program).
3. The Jurisdictional Area Includes:
a. Lands within two hundred feet (200'), as measured on a horizontal
plane, from the OHWM, or lands within two hundred feet (200') from
floodways, whichever is greater;
b. Contiguous floodplain areas; and
c. All marshes, bogs, swamps, and river deltas associated with streams,
lakes, and tidal waters that are subject to the provisions of the State
Shoreline Management Act.
A combination of field data and GIS inventories were used to map Cedar River
shoreline jurisdiction. Floodway and floodplain areas were provided by City of
Renton GIS. Within the Project area, no floodplain extends outside of the
mapped floodway. The mapped floodway overlaps with the estimated ordinary
high water mark (OHWM) on the north bank of the river and extends slightly
beyond it on the south bank. As a result, a buffer of 200 feet was applied to the
Cedar River floodway to form the basis for shoreline jurisdiction. On the south
bank of the river, a delineated wetland (Wetland NRO2) falls within that 200-foot
buffer and extends outside of the 200-foot buffer to the south. Consistent with the
Shoreline Management Act and RMC, this wetland was considered “associated”
with the Cedar River, and the shoreline jurisdiction was extended to encompass
its entire delineated boundary. On the north bank of the Cedar River a potential
wetland, “Cedar North”, was also identified within 200 feet of the OHWM on the
northern bank of the Cedar River, which likely extends outside of the 200-foot
buffer to the north. However, this feature was not delineated. Therefore, the
extent of shoreline jurisdiction on the north side of the Cedar River is
approximated, conservatively to encompass the approximated area of this
wetland.
The Project has been designed to avoid all impacts within shoreline jurisdiction.
Conservatively, this includes avoiding all tree removal and impacts to other
native vegetation within the vicinity of Wetland NRO2 as well as the
approximated boundaries of the Cedar North wetland which defines the
northern extent of the shoreline jurisdiction boundary. Renton and the
Department of Ecology have documented that the Project should be reviewed as
a maintenance and repair shoreline exemption (email communication between J.
Ding and S. Leverette 11.6.17).
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5 R EGULATIONS
5.1 Critical Areas Regulations Exemption
As noted above, most critical areas, including those within shoreline jurisdiction,
are regulated under Section 4-3-050 (Critical Areas Regulations) of the RMC.
According to this section, certain activities, including types of private utility
work within existing easements, are exempt from Critical Areas Regulations
(RMC 4-3-050.C.3). Exempt activities are permitted in applicable critical areas
and critical area buffers according to a table in RMC 4-3-050.C.3. The Project
qualifies as exempt per RMC 4-3-050.C.3.e.iii (Table 3).
As demonstrated in Table 3, the referenced exemption does not apply in flood
hazard areas or wellhead protection areas. The Project proposes no significant
adverse alterations to critical areas that are not covered under the applicable
exemption (Table 3).
Table 3. Excerpt of RMC 4-3-050.C.3 table of exempt activities.
Exempt Activity
Flood Hazard Area Geologic Hazard Area Habitat Conservation Area Streams and Lakes: Type F, Np, & Ns Wellhead Protection Areas Wetlands e. Roads, Parks, Public and Private Utilities18:
iii. Utilities, Traffic Control, Walkways,
Bikeways Within Existing, Improved
Right-of-Way or Easements15
X X X X
Footnotes:
15. Within existing and improved public road rights-of-way or easements, installation, construction,
replacement, operation, overbuilding or alteration of all natural gas, cable, communication, telephone
and electric facilities, lines, pipes, mains, equipment or appurtenances, traffic control devices,
illumination, walkways and bikeways. If activities exceed the existing improve d area or the public
right-of-way, this exemption does not apply. Where applicable, restoration of disturbed areas shall be
completed.
18. Maintenance activities, including routine vegetation management and essential tree removal, and
removal of non-native invasive vegetation or weeds listed by the King County Noxious Weed Board
or other government agency, for public and private utilities, road rights -of-way and easements, and
parks.
In order to receive an approved letter of exemption from the City, a critical area
report and mitigation plan is required per RMC 4-3-050.C.2.c and the following
“Administrator Findings” (RMC 4-3-050.C.2.d) must be true:
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i. The activity is not prohibited by this or any other provision of the Renton Municipal
Code or State or Federal law or regulation;
ii. The activity will be conducted using best management practices as specified by
industry standards or applicable Federal agencies or scientific principles;
iii. Impacts are minimized and, where applicable, disturbed areas are immediately
restored;
iv. Where water body or buffer disturbance has occurred in accordance with an
exemption during construction or other activities, revegetation with native
vegetation shall be required;
v. If a hazardous material, activity, and/or facility that is exempt pursuant to this
Section has a significant or substantial potential to degrade groundwater quality,
then the Administrator may require compliance with the Wellhead Protection Area
requirements of this Section otherwise relevant to that hazardous material, activity,
and/or facility. Such determinations will be based upon site and/or chemical-
specific data.
As explained in detail below, the Project complies with state and federal
regulations, employs best management practices, and follows mitigation
sequencing criteria required by the code (see Section 6). No significant adverse
impacts to critical areas will result from Project activities.
5.2 Critical Area Buffers
In order to avoid, minimize, document, and mitigate for critical area impacts in
accordance with the applicable exemption criteria, required critical area buffers
are described in this section and displayed in Appendix A. Flood hazard areas
and wellhead protection areas do not require buffers. PSE limits, to the extent
feasible, impacts to critical area buffers.
Wetlands and Streams
A summary of relevant wetland and stream critical area classifications and
standard buffer widths provided in the Delineation Report (The Watershed
Company 2016a) and 2017 additional delineation documentation (The Watershed
Company 2017) in Appendices B and C are presented again in Tables 4 and 5,
below.
Standard buffer widths for wetlands outside of shoreline jurisdiction are based
upon the type of land use proposed, wetland category (using the 2014 Ecology
rating system), and habitat score. The proposed land use is not considered low
impact due to the vegetation management requirements of the new lines. For
wetlands within shoreline jurisdiction, the wetland category is based on the 2004
Ecology rating system (RMC 4-3-090.D.2.d.ii) and the minimum buffer width is
based on the category and wildlife function score (RMC 4-3-090.D.2.d.iv).
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Standard buffer widths for streams are based upon the stream type.
Table 4. Summary of wetland critical area classifications and standard buffer widths.
Table 5. Summary of stream critical area classifications and standard buffer widths.
Stream Name Stream Type Standard Buffer Width
(feet)
MR01 – Honey Dew Creek Type F 115
NR01 – Ginger Creek Type Np 75
NR02 Type Ns 50
Cedar River Shoreline 100
Functioning buffers are shown in Appendix A. Functioning buffers are generally
characterized as vegetated upland areas adjacent to wetland and stream critical
areas. Impervious surfaces and development have been removed from standard
buffers to generate functioning buffers so as not to quantify existing impacts as
new Project impacts.
Additionally, RMC requires modification of the standard buffer width for
wetlands and streams in certain circumstances. Buffers have been modified
according to the following provisions:
Wetland
Name
2014 Ecology Wetland Rating
Category
Standard
Buffer
Width
(feet)
Water
Quality
Hydrologic
Function Habitat Total
NR01 5 6 7 18 III 100
NR03 6 5 7 18 III 100
NR04 5 5 6 16 III 100
NR05 5 6 7 18 III 100
Talbot
wetland* -- -- -- -- ~III ~100
2004 Ecology Wetland Rating (shoreline
wetlands)
NR02 12 12 29 53 II 225
Cedar
north* -- -- -- -- ~III ~125
* Wetland not delineated or formally rated; rating is estimated and a moderate habitat score
is presumed to determine approximate buffer width.
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Per RMC 4-3-090.D.2.d.iv.a, buffers for wetlands in shoreline jurisdiction,
… shall not include areas that are functionally and effectively disconnected from
the wetland by a permanent road or other substantially developed surface of
sufficient width and with use characteristics such that buffer functions are not
provided and that cannot be feasibly removed, relocated or restored to provide
buffer functions.
Similarly, per RMC 4-3-050.G.2 footnote 6, for buffers for wetlands outside of
shoreline jurisdiction:
Areas that are functionally and effectively disconnected from the wetland by a
permanent road or other substantially developed surface or sufficient width and
with use characteristics such that buffer functions are not provided shall not be
counted toward the minimum buffer unless these areas can be feasibly removed,
relocated or restored to provide buffer functions.
Therefore, portions of wetland buffers that are effectively disconnected from the
wetland by a road or other permanent development have been removed.
Per RMC 4-3-090.D.2.d.iv.e, the presence of steep slopes adjacent to wetlands in
shoreline jurisdiction also alters the required buffer width as follows:
Increased Buffer for Steep Slopes: Where lands within the wetland buffer have
an average continuous slope of twenty percent (20%) to thirty five percent
(35%), and the required buffer width is less than one hundred feet (100'), the
buffer shall extend to a thirty percent (30%) greater dimension. In all cases,
where slopes within the buffers exceed thirty five percent (35%), the buffer shall
extend twenty five feet (25') beyond the top of the bank of the sloping area or to
the end of the buffer associated with a geological hazard if one is present,
whichever is greater.
Wetlands NR02 and Cedar North are both adjacent to steep slopes, therefore
their buffers have been extended in compliance with this provision.
Finally, per RMC 4-3-050.G.2, footnote 5,
when a required stream/lake buffer falls within a protected slope or very high
landslide hazard area, the stream/lake buffer width shall extend to the boundary
of the protected slope of very high landslide hazard area.
Stream MRO1 (Honey Dew Creek), Stream NRO1 (Ginger Creek), and Stream
NRO2 have had their buffers extended to the top of adjacent slopes in
compliance with this provision.
The altered, functioning wetland and stream buffers described above have been
used as the basis for the critical areas impact analysis and are shown on the maps
in Appendix A.
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Habitat Conservation Areas
Renton has the option to establish buffer areas for activities in, or adjacent to,
habitat conservation areas regulated under Renton’s Critical Areas Regulations
when needed to protect fish and wildlife habitats of importance. Buffers shall
consist of an undisturbed area of native vegetation, or areas identified for
restoration, established to protect the integrity, functions and values of the
affected habitat. Per RMC 4-3-050.G.6.c, buffer widths shall be based on:
1. Type and intensity of human activity proposed to be conducted on the
site and adjacent sites.
2. Recommendations contained within a habitat assessment report.
3. Management recommendations issued by the Washington Department of
Fish and Wildlife.
As noted in Section 4.3.3, the Cedar River and Honey Dew Creek are considered
Habitat Conservation Areas. This report documents available habitat within
those areas, potential impacts and proposed mitigation for Project actions in
compliance RMC 4-3-050.G.6.c. The associated stream buffers and critical area
regulations for streams are expected to adequately protect the Cedar River and
Honey Dew Creek habitat areas for the duration of the Project. No additional
buffer requirements are recommended.
Additionally, in compliance with federal ESA requirements, a Biological
Evaluation has been prepared for the Project. As summarized in that document,
the Project may affect but is not likely to adversely affect ESA-listed species
based upon lack of documented use, lack of suitable habitat, and/or avoidance of
in-water work and vegetation removal where listed species are known to occur.
Geologic Hazard Areas
Geologic hazard areas include steep slopes, landslide hazards, erosion hazards,
seismic hazards, and coal mine hazards. Required buffers for these critical areas
(or lack thereof) is indicated in Table 4, per RMC 4-3-050.G.2. Per City
requirements, these areas have been evaluated by GeoEngineers (Appendix E).
Table 6. Summary of geologic hazard area buffer requirements.
Geologic Hazard Area Buffer Requirements
Steep Slopes
- Sensitive Slopes
- Protected Slopes
Based upon the results of a geotechnical report and/or
independent review, conditions of approval for developments
may include buffers and/or setbacks from buffers.
Landslide Hazards
- Low
- Medium
- High
Based upon the results of a geotechnical report and/or
independent review, conditions of approval for developments
may include buffers and/or setbacks from buffers. Very high
landslide hazards require a 50-foot buffer.
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Geologic Hazard Area Buffer Requirements
- Very High
Erosion Hazards
- Low
- High
None
Seismic Hazards
- Low
- High
None
Coal Mine Hazards
- Low
- Medium
- High
Based upon the results of a geotechnical report and/or
independent review, conditions of approval for developments
may include buffers and/or setbacks from buffers.
Per GeoEngineers, the Project area does not include any mapped very high
landslide hazard areas and, as such, there are no required buffers in the project
area. GeoEngineers does not recommend any additional buffer areas (Appendix
E).
5.3 Shoreline Master Program Regulations
The Cedar River, Class 1 Fish and Wildlife Habitat Conservation Areas and
wetlands within shoreline jurisdiction are regulated under the Renton SMP.
However, the project has been designed to avoid all impacts, including native
vegetation removal, within shoreline jurisdiction. PSE and Renton have sought
and received documentation from the Washington State Department of Ecology
that proposed Project actions within shoreline jurisdiction (spanning wires across
the Cedar River) are exempt from the requirements of a Shoreline Substantial
Development Permit (SSDP) or Shoreline Conditional Use Permit (email
communication between J. Ding and S. Leverette 11.6.17).
6 M ITIGATION S EQUENCING
Pursuant to RMC 4-3-050.L.1.b, PSE has taken steps to avoid and minimize
impacts to the critical areas and associated buffers located in the Project corridor.
Avoidance
Proposed new poles have been sited to avoid any direct impacts to wetlands or
streams. All impacts have been avoided within the shoreline jurisdiction
including within all flood hazard areas. Completely avoiding pole impacts to
geologic hazard areas and wellhead protection areas is not feasible due to the
prevalence of those features in the Project area. Furthermore, pole replacement
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activities associated with the transmission line upgrade must occur in specific
locations for proper functioning of the electrical system due to complex
engineering considerations making pole placement in some critical areas
unavoidable. Where avoidance wasn’t possible, PSE worked with engineers to
minimize impacts through design revisions; such changes reduced pole
footprints and increased line heights to avoid critical area impacts to the extent
feasible.
Temporary impact areas associated with construction access, pole construction
work areas, and stringing sites also avoid critical areas to the extent feasible. For
example, specific pole construction work areas have been adjusted to exclude
critical areas on a pole-by-pole basis.
Minimization
Minimization techniques were utilized during the design process in order to
limit impacts to critical areas and their associated buffers. Minimization
measures included the following:
1. Utilizing the existing transmission line corridor, which has experienced
significant disturbance as a result of adjacent development and ongoing
corridor maintenance.
2. When working within a critical area, limiting the construction
disturbance to the minimum feasible size around each pole and access
point.
3. Installing 230 kV transmission lines between poles with minimal site
disturbance. Where feasible given maximum distance allowed between
poles, the poles will be located outside of critical areas. Transmission lines
will span above critical areas, minimizing ground disturbance, vegetation
removal, and loss of critical area function.
4. Where vegetation removal is required in critical areas, trees will be
accessed by foot, stumps will be left in the ground, and debris will be
chipped or dispersed as appropriate, preventing critical area disturbance
by large heavy equipment.
Compensation
Mitigation will occur in accordance with RMC 4-3-050.L and with best
management practices as required by the exemption criteria. Proposed
mitigation includes restoration of temporary impacts (including maintenance of
slope stability) and wetland buffer enhancement (Appendix F) The mitigation
approach and plans are discussed in Section 8 and 9, respectively.
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7 U NAVOIDABLE P ROJECT I MPACTS
Impact types resulting from the Project have been quantified based upon the
long-term condition of the proposed work areas and existing land cover types in
the corridor. Quantified impacts have been characterized as one of four types
using this analysis and include permanent, conversion, temporary, and no
change. A summary of the impact types based on proposed work and existing
land cover is provided in Table 7.
Permanent impacts are characterized as a change from a vegetated critical area to
a transmission line pole. Impacts that result in vegetation conversion are caused
by vegetation management activities resulting in a shift from forested to shrubby
or herbaceous vegetation. Conversion impacts will be limited to disturbance of
vegetation; soils will remain intact. Temporary impacts will occur in geologic
hazard areas, wetland and stream buffers, and wellhead protection areas as part
of the following activities: pole installation, maintenance, and removal; and
construction access route re-establishment/use. Temporary impacts will be
restored in-place after construction work is complete.
No Project impacts occur in wetlands, streams, flood hazard areas, or in
shoreline jurisdiction. Permanent, conversion, and/or temporary Project impacts
are proposed in erosion hazard areas, steep slope and landslide hazard areas,
coal mine hazard areas, wellhead protection areas, habitat conservation areas,
and buffers associated with wetlands and streams.
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Table 7. Matrix used for determining impact types based upon long-term condition of proposed
activities and existing land cover types in critical areas and associated buffers.
Existing Land Cover Types
Impact Description
Long-Term
Condition1
Forested to
be Removed
Forested to
Remain Understory only Other (mostly lawn) with
under
story
no
under
story
with
under
story
no
under
story Proposed Activities Pole footprint (actual
footprint of pole
structure based on
engineering drawings
from PSE)
Developed P P P P P P
Pole buffer (6 foot
radius outside of pole
footprint)
Mixed
vegetation2 C C T T T T
Access routes (20 foot
width based on
alignments from PSE)
Mixed
vegetation2 C C T T T T
Pole construction work
area
Mixed
vegetation2 C C T T T T
Wire Zone Mixed
vegetation2 C C NC NC NC NC
Managed ROW Mixed
vegetation2 C C NC NC NC NC
Legal ROW Mixed
vegetation2 C C NC NC NC NC
Type of Impact based on proposed activity, long term condition, and existing land cover type: P =
Permanent, C = Conversion, T = Temporary, NC = No Change
1 Long term condition determined in coordination with PSE.
2 Subject to varying height restrictions described in Section 3.3.4.
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7.1 Critical Area Impacts
Wetland and Stream Buffer Impacts
Minor permanent impact is proposed to wetland buffer as a result of one new
pole on the south side of the Cedar River in the outer buffer of Wetland NRO2,
and three increased footprints from Lake Tradition Line replacement poles in the
buffer of the Talbot Wetland. Two existing poles (totaling 12 SF) will be removed
from the overlapping buffers of Wetlands NRO1 and NRO5 and replaced outside
of their buffer area, resulting in the removal of 12 SF of fill within this
functioning buffer area. Following pole removal the holes will be filled in with
dirt and restored with grass seed (Table 8).
Vegetation conversion impacts are also proposed to wetland and stream buffers
in the Project corridor in Renton (Table 8).
Temporary impacts for the establishment of access routes and pole installation
and maintenance will also occur in the buffers of Wetland NR01, Wetland NRO2,
Wetland NR05, and the Talbot Wetland (Table 8).
A qualitative description of buffer impacts can be found in Section 10 (Functional
Lift Analysis) followed by a description of the mitigation activities proposed to
compensate for the impact.
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Table 8. Wetland and stream buffer impacts by wetland and/or stream feature and sub-
basin.
Stream/Wetland Impact Type Area1 of Net
Impact (SF) Source of Impact Lower Cedar River Stream NRO1
(Ginger Creek)
Buffer
Permanent 0 None
Conversion 4,962 Removal of vegetation
Temporary 0 None
Stream NRO2
Buffer
Permanent 0 None
Conversion 311 Removal of vegetation
Temporary 0 None
Wetland NR01
Buffer
Permanent -6 Removal of existing pole
Conversion 1,562 Removal of vegetation
Temporary 8,152 Access route
Wetland NRO2
Buffer
Permanent 13 New pole
Conversion 9,423 Removal of vegetation
Temporary 2,371 Pole work area, access
road
Wetland NRO5
Buffer
Permanent -6 Removal of existing pole
Conversion 313 Removal of vegetation
Temporary 9,813 Access route
Talbot Wetland
Buffer
Permanent 67 Replacement poles2
Conversion 0 None
Temporary 6,220 Pole buffer, pole work
areas
TOTAL1
Lower Cedar River sub-basin
Permanent: 68 SF
Conversion: 15,948 SF
Temporary: 19,235 SF May Creek Stream MRO1
(Honey Creek)
Buffer
Permanent 0 None
Conversion 2,838 Removal of vegetation
Temporary 0 None
TOTAL1
May Creek sub-basin
Permanent: 0
Conversion: 2,838 SF
Temporary: 0
1 Area column does not sum to total impact reported because where wetland/stream buffers overlap total
impact has been adjusted down to count each impact area only once.
2Three Lake Tradition Line poles are being replaced in the buffer of the Talbot Wetland. Replacement
poles are in the same location as existing poles, but have a larger footprint. Only the net increase in
development footprint is counted.
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Habitat Conservation Area Impacts
Three existing poles, totaling approximately 18 SF, will be removed from the
HCA mapped south of the Cedar River, outside of the extent of shoreline
jurisdiction. These poles will be replaced with one new pole totaling 13 SF. Thus,
there will be a net reduction in fill in this HCA. The new pole is located outside
of the 100-foot Cedar River buffer, and the entirety of the shoreline jurisdiction,
as well as outside of all non-shoreline stream and wetland buffers. The pole is
located just north of an existing road and parking area associated with the
Shadow Hawk development. It is not expected to significantly impact habitat in
the area.
Geologic Hazard Area Impacts and Associated Buffer Impacts
Impacts to geologic hazard areas have been reviewed by GeoEngineers based on
PSE’s proposed activities. As stated previously, the main areas of the corridor
associated with geologic hazards are the Honey Dew Creek and Cedar River
drainage areas where several overlapping geologic hazards are mapped. As
such, GeoEngineers focused their review of impacts to this area. New poles will
be installed in erosion hazard areas, landslide hazard areas, steep slope hazard
areas and coal mine hazard areas (Table 9). However, new poles are replacing
existing poles which will be removed. Per GeoEngineers Report (Appendix E),
for poles located in geologic hazard areas, old poles should be cut one to two feet
below the ground surface, leaving the remaining portion of the pole below
ground in place in order to minimize impacts.
Table 9. Geologic hazard area impacts associated with pole replacement in Project area.
Geologic Hazard Area or
Associated Buffer
Number of New Poles1
(and proposed size in
SF)
Erosion Hazard Area 10 (283 SF)
Landslide Hazard Area 9 (239 SF)
Priority Steep Slope Hazard Area 7 (123 SF)
Seismic Hazard Area 0
Coal Mine Hazard Area 18 (478 SF)
1 Several poles are present and/or are proposed in overlapping geologic hazard areas. Poles in table are
counted in each area they occur in. Area based on pole diameter ranging from 3 feet to 6 feet depending
on the pole type.
Vegetation management activities will also result in impacts to geologic hazard
areas. Impacts quantified by canopy removal are presented in Table 10 below as
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vegetation conversion, and are caused by tree removal associated with the
Project. Vegetation conversion quantities presented here were not utilized by
GeoEngineers in their analysis of Project impacts to geologic hazard areas.
GeoEngineers’ review of geologic hazard areas included a site visit to evaluate
the hazard areas identified along the slopes of Honey Dew Creek and the Cedar
River. They determined that PSE’s proposed work is consistent with the
management activities of the existing power line right-of-way and is not
anticipated to impact the mapped geologic hazard area within these drainage
areas (provided no tracked or rubber-tired equipment is used to remove trees).
Their report notes that proposed removal of trees in the Honey Dew Creek
drainage is located upslope of any identified recently active slope failures and is
not anticipated to exacerbate localized slope failures. Recommended mitigation
strategies are discussed in Section 8 of this report.
Refer to the GeoEngineers Report for additional details (Appendix E).
Table 10. Vegetation conversion impacts to geologic hazard areas in the Project area.
Geologic Hazard Area or
Associated Buffer
Vegetation
Conversion
(SF)
Source of Impact
Erosion Hazard Area 19,512 Legal ROW, managed ROW, wire
zone,
Priority Landslide Hazard Area 18,291
Legal ROW, pole work area,
managed ROW, wire zone, access
road, pole buffer
Priority Steep Slope Hazard Area 25,133 Wire zone, legal ROW, managed
ROW, pole work area, pole buffer
Seismic Hazard Area 0 None
Coal Mine Hazard Area 25,424 Legal ROW, managed ROW, wire
zone, access road
Wellhead Protection Area Impacts
Wellhead protection areas are mapped within most of the Project corridor.
Impacts to wellhead protection areas have been reviewed by GeoEngineers
based on PSE’s proposed activities (Appendix E).
Project actions within mapped wellhead protection areas are summarized in
Table 11 below. Impact reported for pole footprints in Table 11 accounts for
where new pole footprints overlap existing pole footprints (only new area of
impact resulting from the new, bigger, pole is counted).
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Table 11. Actions within wellhead protection areas in the Project area.
Wellhead Protection Area Area (SF) Source of Impact
Zone 1
Permanent 791 Pole footprints
Conversion 0 none
Temporary 23,196 Pole work area, access road, pole
buffer
Zone 2
Permanent 706 Pole footprints
Conversion 40,696
Wire zone, managed ROW, access
road, legal ROW, pole work area, pole
buffer
Temporary 131,387 Pole work area, pole buffer, access
road,
1Permanent impact reported for pole footprints accounts for where new pole footprints overlap existing pole
footprints. Only new area of impact resulting from the new, bigger, pole is counted.
As with their analysis of proposed actions within geologic hazard areas,
GeoEngineers’ review focused on the Honey Dew Creek and Cedar River
drainage areas. They determined that PSE’s proposed work in wellhead
protection areas is consistent with the management activities of the existing
power line right-of-way and is not anticipated to impact the mapped wellhead
protection areas within these drainage areas (provided no tracked or rubber-tired
equipment is used to remove trees). Recommended mitigation strategies are
discussed in Section 9 of this report.
Refer to the GeoEngineers Report for additional details (Appendix E).
8 M ITIGATION A PPROACH
8.1 Wetland and Stream Buffer Mitigation Ratio
In general, alterations to critical areas or buffers must provide restoration or
mitigation to ensure that they do not result in a loss of critical area functions or
values. For exempt activities, mitigation is required consistent with RMC 4-3-
050.L (Mitigation, Maintenance, and Monitoring) unless otherwise waived by the
Administrator, per RMC 4-3-050.C.2.c. While RMC 4-3-050.C.2.b states that
exempt activities do not need to comply with mitigation ratios, the requirements
of RMC 4-3-050.L clarify that all mitigation shall be based on best available
science (e.g. mitigation ratios). Therefore, mitigation ratios have been utilized in
this mitigation approach.
As described in Section 7, the vast majority of wetland and stream buffer impacts
for the Project are vegetation removal/conversion. Interagency guidance for
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Renton Critical Areas Report
42
mitigating vegetation conversion impact (in wetlands, specifically) is as follows
(Ecology et al. 2006):
Loss of functions due to the permanent conversion of wetlands from one type to
another also requires compensation. For example, when a forested wetland is
permanently converted to an emergent or shrub wetland (e.g., for a utility right-
of-way) some functions are permanently lost or reduced.
The ratios for conversion of wetlands from one type to another will vary based
on the type and degree of the alteration, but they are generally one-half of the
typical ratios for permanent impacts.
Where functioning wetland or stream buffers are impacted by a conversion of
vegetation (not fill or grading), the proposed minimum mitigation ratio to off-set
impacts is 0.5:1, consistent with the guidance for this type of impact to wetland
areas.
Temporary wetland and stream buffer impacts will be restored in-place at a 1:1
ratio. Permanent buffer impacts will be mitigated at a ratio of 1:1, consistent with
Renton’s standard provisions.
8.2 Wetland and Stream Buffer Mitigation Location
In general, mitigation sites are more successful when combined into fewer larger
areas, rather than piecemealed across several smaller sites. Furthermore,
mitigation on properties which are publicly owned or PSE-owned would be
more accessible and ultimately more successful compared to privately owned
properties. The City of Renton has directed PSE to avoid City-owned property in
locating a suitable mitigation site. Therefore, PSE properties were evaluated for
mitigation potential in the Lower Cedar River sub-basin, where the majority (85
percent) of Project impacts occur.
The degraded buffer of Wetland NR01, which extends onto a PSE-owned parcel
east of Cedar Ridge Drive SE at the southern end of the Project corridor near the
Talbot Hill substation, provides buffer enhancement mitigation opportunities.
9 M ITIGATION P LAN
9.1 Wetland and Stream Buffer Mitigation
The mitigation plan is designed to enhance wetland buffer in the Lower Cedar
River sub-basin and increase the number of habitat structures in the Honey Dew
Creek buffer. The plan accounts for utility maintenance needs, site topography,
habitat connectivity, and vegetation height restrictions.
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Revised January 2019
43
The Mitigation Plan (Appendix F) includes notes that fulfill the mitigation and
monitoring requirements of the RMC and provide clear direction for mitigation
goals, performance standards, monitoring and maintenance protocols, and
contingencies for the duration of the required five-year monitoring period.
The minimum size of the mitigation area (Table 12) was calculated based upon
wetland and stream buffer impacts and the mitigation ratios presented in Section
8.1.
Table 12. Calculation of mitigation needs for wetland and stream functioning buffer
impacts.
Impact Type Net Area of
Impact (SF)
Proposed
Mitigation
Ratio
Mitigation
Required (SF)
Lower Cedar
River Sub-basin
Permanent 68 1:1 68
Conversion 15,948 0.5:1 7,974
Total: 8,042
May Creek Sub-
basin
Permanent 0 1:1 0
Conversion 2,838 0.5:1 1,419
Total: 1,419
Grand Total: 9,461
Required minimum buffer mitigation for the Project in Renton is 9,461 SF.
Opportunity to fulfill this mitigation need exists in the buffer of Wetland NR01,
on parcel #2023059001.
Mitigation for the Lower Cedar River sub-basin impacts, as proposed in the
attached plan (Appendix F), consists of 9,500 SF of wetland buffer enhancement.
Proposed mitigation activities include invasive species removal and installation
of native small trees, shrubs, and groundcover plants. In the Honey Dew Creek
buffer, snag creation will mitigate for some impacts to habitat occurring within
the May Creek sub-basin.
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A five year maintenance and monitoring plan is included in accordance with the
requirements of RMC 4-3-050.L.3. See the Mitigation Plan in Appendix F for
specific details.
9.2 Geologic Hazard Area Mitigation
GeoEngineers has proposed mitigation strategies to minimize impacts to
geologic hazard areas in the corridor in their analysis report (Appendix E). As
stated previously, and in their report, with implementation of these strategies,
proposed activities are not expected to impact the geologic hazard areas in the
Honey Dew Creek and Cedar River drainage areas and are consistent with the
management activities of the existing corridor. They recommend replacement
planting with native shrubs within the Honey Dew Creek drainage to increase
root strength after tree removal and to reduce impacts within the landslide
hazard area.
Pole Replacement
Pole replacement activities are proposed in erosion hazard areas, landslide and
steep slope hazard areas, and coal mine hazard areas. For pole replacement
activities, the disturbed area will be stabilized using BMPs that reduce potential
impacts including plant replacement, seeding, or hog fuel application in areas of
bare soil and scattering chipped wood or tree debris. Soil removed from new
pole excavations will be scattered into vegetation and away from landscaped
areas. If the work area is wet or has standing water, driving mats will be used
under all equipment and all soils excavated for pole installation will be removed
from the site for offsite disposal. The requirements of a Sediment and Erosion
Control Plan will be addressed in the Project-specific TESC Plan and
Construction Stormwater Pollution Prevention Plan (CSWPPP). Additionally, for
poles located in geological hazard areas or associated buffers, the old poles will
be cut off approximately 1-2 feet below the ground surface and the remaining
underground portion of each pole left in place to minimize ground disturbance.
Vegetation Management
Options for mitigation of vegetation management and tree removal in geologic
hazard areas include limiting disturbance to these areas by large equipment
(only by foot and hand-cutting with chainsaws), leaving cut stumps of snags in
place, and chipping or scattering tree debris where feasible. GeoEngineers
recommends trees are felled across the fall line and left perpendicular to the
slope if they are not chipped. Within the Honey Dew Creek drainage,
replacement planting with native shrubs is recommended to increase root
strength after tree removal and to reduce impacts within the landslide hazard
area.
The Watershed Company
Revised January 2019
45
Temporary Work Areas
Where vegetation clearing is required to reestablish access on existing trails or
old access routes, BMPs will be implemented. These BMPs may include, but are
not limited to outsloping road surfaces, crowning road surfaces (where
appropriate, such as at ridge tops and where roads climb gently inclined
surfaces), and installing water bars or rolling dips at regularly spaced intervals to
avoid concentrating surface water flow along the road surface. After
construction, disturbed areas should be graded to a stable free-draining
configuration, treated with appropriate erosion control measures, and seeded.
Most, if not all, access routes can be abandoned following construction using
erosion control measures and seeding.
10 F UNCTIONAL L IFT A NALYSIS
Impacts to wetland and stream functional buffers have been qualitatively
assessed in addition to the quantitative analysis in Section 7. For the purposes of
this section, the pre-existing condition of the Project area is compared against the
proposed post-Project condition to ensure that no net loss of critical area
functions is achieved.
In general, proposed wetland and stream buffer impacts are located in areas that
are disturbed and dominated by invasive plants such as non-native blackberry.
The majority of these impacts are classified as a vegetation conversion that
involve removal of native and non-native trees from buffer areas. Buffer impacts
are proposed in three main areas - Honey Dew Creek, the Cedar River ravine
(outside of shoreline jurisdiction), and the Talbot substation to Shadow Hawk
development portion of the corridor south of the Cedar River ravine. Except for
Honey Dew Creek, all other wetland and streams identified in the study area are
located in the Lower Cedar River sub-basin. Buffer conditions of these features
can be generally described based on location. Table 13 summarizes impacts,
existing conditions, and proposed conditions in the three proposed impact areas.
The functional lift analysis describes how the mitigation plan will provide
equivalent or greater critical area functions when compared to existing
conditions overall.
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Table 13. Descriptions of general impact area conditions and proposed changes.
Critical Area Existing and Proposed Conditions May Creek Sub-basin Honey Dew
Creek Buffer
Existing Conditions: Honey Dew Creek is the only wetland or stream
critical area in the Project area located in the May Creek sub-basin. The
Honey Dew Creek buffers are predominantly forested with native tree
species and include steep, protected slope areas. The forest understory is
degraded in places where invasive weeds are patchy and homeless
encampments have removed understory vegetation and compacted soils.
Proposed Conditions:
Removal of 18 trees from forested buffer area to accommodate new,
higher voltage transmission lines.
- 2,838 SF of canopy will be lost, predominantly near the outer
portion of the buffer on the north side of the creek.
Where suitable, standing snags will be created from trees that require
removal to mitigate for some habitat impact to the buffer area. Other
buffer impacts will be mitigated in the buffer of Wetland NR01 in the
Lower Cedar River sub-basin through invasive species removal and
native vegetation planting. Lower Cedar River Sub-basin Talbot to
Shadow Hawk
Area Wetland
and Stream
Buffers
(Wetlands
NRO1, NRO5,
Talbot Wetland,
and Stream
NRO1)
Existing Conditions: The buffers of wetland and streams located south of
the Cedar River ravine between the Talbot Hill substation and the Shadow
Hawk neighborhood are degraded due to the existing use of the corridor.
This area is in close proximity to residential development and is part of the
managed corridor. Roads, parking lots, commercial development, and
trails established from overgrown access routes are also present in this
area.
The Talbot Hill area is also utilized by an extensive number of co-located
critical utilities which also have vegetation management requirements.
The BPA easement parallels the Project area in this portion of the corridor.
Vegetation in this area is dominated by small trees, shrubs, and grasses.
Areas are currently mowed that are within the overlapping BPA easement.
Invasive species present include but are not limited to Himalayan
blackberry, Scotch broom, and reed canarygrass.
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Revised January 2019
47
Critical Area Existing and Proposed Conditions
Proposed Conditions:
Conversion from forested buffer area to shrub buffer area to
accommodate new, higher voltage transmission lines.
Temporary impacts associated with establishment of access routes
and pole installation and maintenance.
Removal of two existing poles from buffer area, resulting in a net
reduction of 12 SF of buffer fill.
Installation of three replacement poles for the Lake Tradition Line in
the same area as existing poles, but with a larger footprint resulting in
67 square feet of new developed area.
Corridor will continue to be maintained.
Impacts will be mitigated through enhancement of Wetland NRO1
buffer near Ginger Creek.
Cedar River
Ravine Wetland
and Stream
Buffers (Wetland
NRO2, and
Stream NRO2)
Existing Conditions: The buffers of wetland and streams located in the
Cedar River ravine contain a mix of native and nonnative vegetation; the
canopy is dominated by native trees, while the understory contains native
plants and localized, dense patches of Himalayan blackberry and invasive
knotweed.
Proposed Conditions:
One new pole in the outer buffer of Wetland NRO2, south of the Cedar
River.
Conversion from forested buffer area to shrub buffer area to
accommodate new, higher voltage transmission lines.
Temporary impacts associated with establishment of access routes
and pole installation and maintenance.
Impacts will be mitigated through buffer enhancement of Wetland
NRO1 including:
- Removal of invasive vegetation
- Installation of native, transmission-line appropriate
vegetation, including low-growing trees and shrubs
- Snag dead trees in the overlapping wetland and stream buffer
to remain as habitat features
May Creek Sub-basin
Honey Dew Creek
As summarized in Table 13, 2,838 SF of vegetation conversion impact is
proposed within the Honey Dew Creek buffer. This impact is predominately in
the area of buffer which has been expanded to encompass the adjacent steep
slopes, per code requirements (See Section 5.2.1). Eighteen (18) trees total are
proposed for removal.
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Trees proposed for removal are assumed to provide some water quality and
hydrologic functions through interception of water (rainfall) and uptake of
groundwater and nutrients. While these trees and their associated functions will
be removed, the understory and adjacent tree canopy to remain will be left in its
existing condition. The effect of limited tree removal on water quality and
hydrologic buffer functions is not expected to be significant.
Removal of canopy may reduce the structural and vegetative species diversity of
the stream buffer areas as well as reduce forage opportunities for some urban
wildlife species. However, the overall character and habitat functions of the
buffer is not expected to change significantly as a result of the limited vegetation
management proposed. Additionally, the existing trees that are not compatible
with the 230 kV lines will be topped and “snagged” in order to provide
additional habitat. Areas that will experience temporary disturbance will be
replanted with native transmission line compatible species.
Net Condition
The impacts associated with tree removal/snagging in the Honey Dew Creek
buffer are not expected to significantly change the water quality or hydrologic
functions of the stream buffer area compared to existing conditions. A slight
modification in the variety of foraging habitat and vegetative structure for urban
wildlife species is anticipated. However, the overall vegetation composition of
the area is not expected to change substantially.
Lower Cedar River Sub-basin
Wetlands NRO1, NRO5, Talbot Wetland and Stream NRO1
Within the Talbot to Shadow Hawk area the majority of wetland and stream
buffer impact is proposed in the buffer of Stream NRO1 (Ginger Creek) due to
vegetation conversion resulting from the removal of eleven trees. As stated
previously, trees proposed for removal are assumed to provide some water
quality and hydrologic functions through interception of water (rainfall) and
uptake of groundwater and nutrients. While these trees and their associated
functions will be removed, the affected area will be left to become revegetated,
likely with herbaceous or shrub vegetation. The water quality and hydrologic
functions provided by potential replacement vegetation is expected to be
comparable in water quality and hydrologic function to the existing small trees.
Therefore, the net effect on water quality and hydrologic buffer functions
anticipated from removing these trees from respective buffer areas, is not
expected to be significant.
Removal of canopy is expected to reduce the structural and vegetative species
diversity of the stream buffer areas as well as reduce forage opportunities for
some urban wildlife species. However, the overall character and habitat
The Watershed Company
Revised January 2019
49
functions of the buffer (i.e., managed corridor dominated by non-native species)
is not expected to change significantly as a result of the limited vegetation
management proposed.
Temporary impacts will incorporate standard BMPs and temporary erosion and
sediment control (TESC) measures to minimize impacts to downstream water
quality and hydrologic functions of the critical area buffer. Vegetation impacted
in temporary work areas is expected to rebound within one growing season.
Net Condition
Vegetation conversion to these buffers is not expected to significantly change the
water quality or hydrologic functions of the buffer areas compared to existing
conditions. A slight reduction in the variety of foraging habitat and vegetative
structure for urban wildlife species may occur. However, the overall vegetation
composition of the area is not expected to change substantially due to the
managed character of the corridor in this area. Restoration of impacts will
include planting of native transmission line compatible species in those areas
that are disturbed.
Wetland NRO2, and Stream NRO2
All impacts to wetland and stream buffers within the Cedar River ravine
(Wetland NR02 and Stream NR02) are located outside of shoreline jurisdiction,
within the outer portion of the combined buffer area south of the Cedar River. As
stated previously trees perform water quality and hydrologic functions through
interception of rainfall and uptake of groundwater and nutrients. Native trees
also provide important habitat functions.
Tree removal is not expected to significantly disturb understory vegetation and
soils. Trees proposed for removal in these buffer areas are also within geologic
hazard areas and will be accessed by foot and removed by hand-cutting with
chainsaws per GeoEngineers recommendations. In addition, stumps will remain
in the ground and tree debris scattered within the ROW. Areas that will
experience temporary disturbance will be replanted with compatible native
species.
Net Condition
Restoration activities in the buffer of Wetland NR01 are expected to maintain
water quality, hydrologic, and habitat functions of buffer areas in the Lower
Cedar River sub-basin when compared to the existing conditions. Existing and
proposed dense, native trees and shrubs are expected to compensate for the loss
of water quality and hydrologic functions provided by larger trees. Native plants
and the creation of snags will provide cover and forage opportunities for
wildlife.
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11 D ISCLAIMER
The information contained in this report is based on the application of technical
guidelines currently accepted as the best available science. All discussions,
conclusions and recommendations reflect the best professional judgment of the
author(s) and are based upon information available at the time the study was
conducted. All work was completed within the constraints of budget, scope, and
timing. The findings of this report are subject to verification and agreement by
the appropriate local, state and federal regulatory authorities. No other warranty,
expressed or implied, is made.
The Watershed Company
Revised January 2019
51
R EFERENCES
Ding, Jill and S. Leverette. Email Communication. 11.6.17.
Environmental Science Associates (ESA). May 2017. Energize Eastside Project: Phase 2
Draft Environmental Impact Statement. Prepared for the Cities of Bellevue,
Newcastle, Redmond, and Renton. Available online:
http://www.energizeeastsideeis.org/library.html#phase2deis
GeoEngineers. 2017. Revised Targeted Critical Areas Geologic Hazard Evaluation:
Energize Eastside Project in Renton, WA. Prepared for PSE.
IUCN SSC Amphibian Specialist Group. 2015. Anaxyrus boreas. The IUCN Red List of
Threatened Species 2015: e.T3179A53947725. Accessed 20 June 2017:
http://dx.doi.org/10.2305/IUCN.UK.2015-4.RLTS.T3179A53947725.en.
Lewis, J.C. and J.M Azerrad. 2003. Pileated Woodpecker. Pages 29-1 – 26-9 in E. Larsen,
J.M. Azerrad, N. Nordstrom, editors. Management Recommendations for
Washington’s Priority Species, Volume IV: Birds. Washington Department of
Fish and Wildlife, Olympia, Washington, USA
Puget Sound Energy. (n.d.) Avian Protection Program Brochure. Accessed 12 July 2017:
https://pse.com/aboutpse/PseNewsroom/MediaKit/4483_Avian_program_brochu
re.pdf
The Watershed Company. May 2016a. City of Renton Critical Areas Delineation Report:
Puget Sound Energy – Energize Eastside Project. Prepared for PSE. Available
online: http://www.energizeeastsideeis.org/library.html.
The Watershed Company. May 2016b. City of Renton Tree Inventory Report: Puget
Sound Energy – Energize Eastside Project. Prepared for PSE. Available online:
http://www.energizeeastsideeis.org/library.html.
Washington Department of Ecology (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 #06-06-011a.
Olympia, WA.
Washington Department of Fish and Wildlife (WDFW). 2008. Priority habitats and
species list. Olympia, WA 295 pp.
PSE Energize Eastside Project
Renton Critical Areas Report
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Washington Department of Fish and Wildlife (WDFW). 2013. PHS Statewide List and
Distribution by County Excel Spreadsheet. Accessed September 2017:
http://wdfw.wa.gov/conservation/phs/list/.
Washington Department of Fish and Wildlife (WDFW). 2017. SalmonScape. Accessed
October 2017: http://apps.wdfw.wa.gov/salmonscape/.
A P P E N D I X A
Critical Area Assessment Maps
B l a c k R i v e r
E a s t L a k eW a s h i n g t o n- B e l l e v u e S o u t h
E a s t L a k e
W a s h i n g t o n
- R e n t o n
L o w e rC e d a rR i v e r
M a y C r e e kW a t e r- L a k eW a s h i n g t o n
W e s t L a k eW a s h i n g t o n -S e a t t l e S o u t h
1
2
3
4
5
6
7
8910
11
Newcastle
Renton
Newcastle
King County
Renton
King County
Renton Segment of PSE Route 1 PSE, TWC
PSE Route outside of Renton SegmentPSE
Map Page Extent (numbered)TWC
Basin BoundaryKC
TrailsCON
Road CenterlinesCOB
City LimitKC
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P - C O V E R PA G E
§¨¦405
§¨¦90
¬«169
0 750 1,500
Feet
o
Notes:
1. Critical areas were defined within a 100' corridor along the existing
powerline corridor.
2. Map pages highlighted are where critical areas, as designated in Renton
Municipal Code, are mapped within the Renton corridor. All other map pages
were omitted.
3. Only those steep slopes designated as priority through geotechnical field
investigation are mapped within the corridor. Please refer to discussion in
Critical Areas Report.
¬«900
Data sources: Puget Sound Energy (PSE), The Watershed Company (TWC), City of Renton (COR), King County (KC), and HDR. Aerial imagery from PSE, 2011.
King County
3/6
N E W P O R T C T N E
125TH AVE SE
NEWPORT CT NE
NE 21ST STP S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet o1
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
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Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
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Wire Z on e PS E
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3/5 3/5
STREAM MR01 [HONEYDEW CREEK]
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o2
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
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Limit o f F unctioning Buffer Area TW C
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Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
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City L imit KC
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D De a d Tre e s to R e mo ve TW CV
NE 17TH PL
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o3
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
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Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
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Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
Sh ore lin e Jurisdiction based on ap pro xima te extent of Cedar Northwetland bo u ndary.
1/1
CEDAR NO RTHWETLAND -ESTIM ATED
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o4
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
WETL AND NR0 2
CEDARNORTH W ETLAND- ESTI MATED
M A P L E V A L L E Y H W Y
C E D A R R I V E R[D E L I N E AT E D S O U T H E R NEXTENT ON LY ]
S
T
R
E
A
M
N
R
0
2
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o5
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
WETL AND NR0 3
WETL AND NR0 2
RIVERVIEW PARK WALK
CEDAR RIVER TRAIL
STREAM NR02P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o6
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
0/9
SE 8TH ST
HARRINGTON PL SEHARRINGTON PL SEKIRKLAND AVE SE
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o7
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
0/8
0/8
0/8
0/8
0/9
0/9 0/9
0/1 0
0/1 0 0/1 0
WETL AND NR0 4
HARRINGTON PL SESE 8TH STSE 8TH PLSE 10TH STHARRINGTON PL SE
H A R R IN G TO N PL SE115 -0/8
115 -0/8
115 -0/9115 -0/9
115 -0/9
115 -0/10 115 -0/10
115 -0/10
STREAM NR02
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet o8
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
0/7
WETL AND NR0 1
WETL AND NR0 5
NR05 -ESTIM ATED
STREAM NR01[GINGER CREEK]
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet o9
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
0/6
WETL AND NR0 1
WETL ANDNR05
WETL AND NR0 5
NR05 -ESTIM ATED
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet o10
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
0/3
0/4
0/4
0/3
0/3
0/3
0/4
0/4
0/4
TAL BO T W ETLAND- ES TIM ATED BEACON WAY SACCESS RD
115 -0/3
115 -0/3
115 -0/3
115 -0/4
115 -0/4
115 -0/4
P S E E E 2 3 0 - R E N T O N C R I T I C A L A R E A A S S E S S M E N T M A P
Da ta so urce s: Pu g et So un d Ene rg y (PSE), Th e Wat ershed Company (TWC), City of Renton (CO R), King County (KC), Washington Department of Fish and Wildlife (WDFW) and HDR. Aerial imagery from PSE, 2011.
§¨¦405
Renton
0 20 40
Feet
o11
Note s :1. Critica l are as we re d efin ed w ith in a 1 00 'co rrido r a lon g th e existin g t ran smissio n lin ecorridor.2. Acce ss ro ute s sh o wn a t t ypica l widt h of 2 0 fe et .3. De te rmine d in t he f ie ld b y g e ot ech n ica lconsultant. Se e d iscu ssion in Critica l Area sReport.4. We llh ea d Pro tect io n Are a s cove r mo st o f th eproject are a , a nd a re n ot sho w n fo r map p in gpurposes. Se e CAI A re p ort fo r impa cts.
UV900
UV169
N e w c a s t l e
Cr itic alAreas
De lin ea ted Stream BoundaryTW C
De lin ea ted Wetland BoundaryTW C
Estimat ed Wetland BoundaryTW C
St rea mTW C
Wet la nd TW C
Est ima te d WetlandTW C
Limit o f F unctioning Buffer Area TW C
Co mb in e d Functioning Wetland/Stream BufferAreaTWC- w hite sh a din g
Prio rit y Ste ep Slo pe s3 TW C
Ero sion H a za rd CO R
Prio rit y L an dslide H a zard Are a s CO R
Co al Min e Ha zard CO R
Se ismic Ha zard CO R
Sh o reline Ju risd iction TW C
Flo o dw a yCO R
Flo o dp lain CO R
....Prio rit y H ab it at WD FW
Imp ac tsWire sPS E
La ke Tra d it io n 115 k Wire sPS E
!?Exist in g Po le s to b e Re mo ved PS E
!H Exist in g Po le s to b e Re ta ine d PS E
Wire Z on e PS E
Ma n ag e d Righ t-o f-Wa y PS E
Ma int ain ed L eg a l RO WPS E -p a le ye llo w sha d in g
Pro p ose d Acce ss R ou te s 2 P SE
%%,Pro p ose d Pole Fo o tp rin ts PS E
%%,Pro p ose d L ake Trad ition Po le F oo tp rints PS E
#*Pro p ose d String ing Site sHDR
St ud y Area TW C
City L imit KC
D Tre e s t o Re mo veTW C
D De a d Tre e s to R e mo ve TW CV
A P P E N D I X B
2016 Delineation Study
C ITY OF R ENTON C RITICAL A REAS
D ELINEATION R EPORT
Puget Sound Energy – Energize
Eastside Project
Prepared for:
Jens Nedrud
Puget Sound Energy
355 10th Avenue NE
Mail Stop: EST03W48
Bellevue, WA 98004
Prepared by:
May 2016
The Watershed Company
Reference Number:
111103
The Watershed Company Contact Person:
Jennifer Creveling, Senior Biologist
or Katy Crandall, Ecologist
Cite this document as:
The Watershed Company. May 2016. City of Renton Critical
Areas Delineation Report: Puget Sound Energy – Energize
Eastside Project. Prepared for PSE.
The Watershed Company
May 2016
i
T ABLE OF C ONTENTS
Page #
1 Introduction ......................................................................................... 1
1.1 Background and Purpose .................................................................................. 1
1.2 Methods ............................................................................................................ 4
2 Site Description .................................................................................. 5
3 Critical Areas ....................................................................................... 5
3.1 Wetlands ........................................................................................................... 6
3.2 Streams ............................................................................................................ 7
3.3 Wildlife and Habitat ........................................................................................... 8
3.4 Critical Area Classifications and Standard Buffers........................................... 11
3.4.1 Wetlands ........................................................................................................... 11
3.4.2 Streams ............................................................................................................. 11
4 Mitigation Opportunities .................................................................. 12
4.1 Segment M (Honey Dew Creek Ravine) .......................................................... 12
4.2 Segment N (near Talbot Hill Substation) ......................................................... 12
Appendix A
Critical Area Delineation Maps
Appendix B
Wetland Determination Data Forms
Appendix C
Wetland Rating Forms
PSE 230kV Route
Renton Delineation Report
City of Renton Critical Areas Delineation Report - II
L IST OF F IGURES
Figure 1. Map of proposed Oak and Willow routes from the Energize Eastside website.
The Oak route is depicted in green while the Willow route variation is
shown in orange. ...................................................................................... 2
Figure 2. Overview of the study area corridor in the City of Redmond including the
southern portion of Segment M and Segment N. ...................................... 3
Figure 3. Location of osprey nest in the vicinity of Segment N in the City of Renton. .... 10
Figure 4. General area (yellow) where mitigation opportunities exist in Segment M ..... 12
Figure 5. General area (yellow) where mitigation opportunities along Segment N. ....... 13
L IST OF T ABLES
Table 1. Wetland rating and associated buffer width. ................................................... 11
Table 2. Summary of stream classifications and associated standard buffer widths. .... 11
The Watershed Company
May 2016
1
C ITY OF R E NTON
D ELINEATION R EPORT
P UGET S OUND E NERGY – E NERGIZE E ASTSIDE P ROJECT
1 I NTRODUCTION
1.1 Background and Purpose
The purpose of this report is to identify and document potential critical areas
associated with Puget Sound Energy’s (PSE’s) Energize Eastside project. The
Energize Eastside project proposes to build a new electric substation and higher
capacity transmission lines to serve homes and businesses on the Eastside.
Current route options include ‘Oak’ and ‘Willow’ routes that will extend from
Redmond to Renton (Figure 1). Each route option includes a set of PSE-labeled
segments. The Oak route comprises Segments A, C, E, G2, I, K2, M, and N. The
Willow route comprises Segments A, C, E, J, M, and N. This report addresses
critical areas located along the proposed routes in the City of Renton, and
includes PSE-labeled Segment N and a portion of Segment M 1 (Figure 2).
The length of the study area corridor in the City of Renton is approximately 3.7
miles beginning south of May Creek and continuing south to the Talbot Hill
substation (Figure 2). At the direction of PSE, the study area excluded the lower
portion of the Cedar River ravine because there are no pole placement locations
nor anticipated PSE development in this area. In this location, the study area
was defined as follows: on the south side of the ravine, survey limits included
the area approximately 425 feet north-northwest beyond the existing structure(s);
and on the north side of the ravine, survey limits included the area
approximately 250 feet south-southeast beyond the existing structure(s). The
study area corridor includes two existing 115 kV transmission lines spaced
approximately 50 feet apart on center. Each line is composed of three conductors
(wires) connected to H-frame pole structures. The study area corridor is
approximately 100 feet wide.
1 PSE Segments M and N comprise Phase 2 Draft Environmental Impact Statement (DEIS) Segment 3.
PSE 230kV Route
Renton Delineation Report
2
Figure 1. Map of proposed Oak and Willow routes from the Energize Eastside website.
The Oak route is depicted in green while the Willow route variation is
shown in orange.
The Watershed Company
May 2016
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Figure 2. Overview of the study area corridor in the City of Renton including the
southern portion of Segment M (red) and Segment N (green).
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Renton Delineation Report
4
1.2 Methods
Limits of the study area were determined in the field using aerial maps, GPS, and
by measuring 25 feet out from the center of each pole set.
Public-domain information on the study area corridor was reviewed for this
critical areas study. These sources include USDA Natural Resources
Conservation Service (NRCS) soil maps, U.S. Fish and Wildlife Service National
Wetland Inventory (NWI) maps, Washington Department of Fish and Wildlife
interactive mapping programs (PHS on the Web and SalmonScape), City of
Renton’s online mapping application (COR Maps), and King County’s GIS
mapping website (iMAP).
The study area corridor was evaluated for wetlands using methodology from the
Regional Supplement (Corps 2010). The wetland boundary was determined on
the basis of an examination of vegetation, soils, and hydrology. Areas meeting
the criteria set forth in the Regional Supplement were determined to be wetland.
Soil, vegetation, and hydrologic parameters were sampled at several locations
along the wetland boundary to make the determination. Data were recorded at
three of these locations. Data sheets are included in Appendix B.
Updates to the City of Renton’s critical areas regulations occurred after field
work was conducted in the City of Renton. Renton’s wetland classification
system changed as a part of these updates. Delineated wetlands have been re-
classified using the 2014 Rating System (Hruby) currently cited in the Code,
based on observations of site conditions and aerial photos. Wetland Rating
Forms and Figures are included in Appendix C.
Watercourses were determined to be streams if they met the definition provided
by the City of Renton. The center-lines of streams in the study area were
recorded in the field. Streams were classified according to the Renton Municipal
Code.
Wetland boundaries, stream center-lines, data points, and other features (such as
culverts) were GPS-located using a hand-held Trimble Geo-XH unit. Following
field location, the GPS data was differentially corrected using GPS Pathfinder
Office and exported into ESRI ArcGIS software for mapping. Stream and
wetland delineation maps are included in Appendix A.
Incidental wildlife observations and detections were recorded during field
studies and summarized in Section 3.3 of this report.
Possible mitigation opportunities were noted during field studies. The
approximate extent of these areas is shown on aerial photos included in Section 5
of this report.
The Watershed Company
May 2016
5
2 SITE D ESCRIPTION
The study area corridor in the City of Renton is dominated by urban land uses.
The majority of the corridor passes through parcels zoned residential,
commercial, or industrial. Within the residential areas, the corridor passes
through several distinct neighborhoods; from north to south, these include
Glencoe, Honey Creek Ridge, Sunset, Liberty Ridge, and Shadow Hawk. The
largest patch of remaining undeveloped land is located adjacent to the Cedar
River and zoned Resource Conservation (RC).
The study area corridor is primarily located in the Cedar-Sammamish Watershed
(WRIA 8). Within this watershed, the north end of the study area drains to the
May Creek basin while the remainder is located in the Lower Cedar River
drainage basin. At the southern end of the corridor, near the Talbot Hill
substation, the study area drains into the Black River basin of the Duwamish-
Green Watershed (WRIA 9). The study area corridor in the City of Renton is
located in Township 23N, Range 05E, Sections 4, 9, 16, 20, and 21.
Most of the study area corridor in the City of Renton has been developed.
Vegetation in residential, commercial, and industrial areas can be generally
described as maintained yards or landscaped. Remaining vegetated areas are
often dominated by invasive plants including Himalayan blackberry and reed
canarygrass. Forested patches are limited to topographically low regions near
the Cedar River and Honey Dew Creek.
3 C RITICAL A REAS
A total of one wetland and four streams are located along the proposed Energize
Eastside corridor in the City of Renton. All are located in the Cedar-Sammamish
Watershed (WRIA 8). Sign or presence of any wildlife species or habitat areas
that may be regulated by the City were also noted and are described in this
section.
For the purposes of this study, the nomenclature used to identify critical areas
has been based on the PSE segment in which a feature is located, and the local
jurisdiction. Critical areas were then numbered sequentially, in the order in
which they were inventoried. For example, the first wetland inventoried as a
part of this study on Segment N in Renton is called “NR01.”
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3.1 Wetlands
Wetland NR01
Wetland NR01 is a slope wetland located near the southern end of the study
area, between SE Cedar Ridge Drive and the Shadow Hawk neighborhood
(Appendix A, Page No. 31). Vegetation is dominated by palustrine scrub-shrub
and palustrine emergent vegetation classes. Common plants observed include
hardhack spirea and reed canarygrass. Sampled wetland soils (Appendix B; DP-
1) were a gravelly loam and met the criteria for hydric soil indicator Redox Dark
Surface (F6). Primary hydrology indicators were not observed at the test pit, but
saturation and/or surface water was present in small depressions in the wetland
during field investigations. Conditions at the data point met the criteria for two
secondary hydrology indicators. Wetland NR01 is primarily supported by
groundwater and supplemented by surface water and precipitation. This
wetland is rated as a Category III wetland.
Unmapped Wetland Areas
Two wetland areas are mapped on COR maps underneath the powerlines
between the Cedar River Trail and the Cedar River. As described in the Methods
section above, this wetland area was not verified or classified as part of this
study. There are neither pole placement locations nor anticipated PSE
development in this area. Their approximate locations have been sketched onto
the Critical Areas Maps (Appendix A).
Non-wetland Areas
A possible wetland feature is mapped by NWI and the City of Renton on a parcel
located west of Monroe Avenue NE (parcel number 1623059059). The parcel is
undeveloped. A review of the City’s online public records indicates this area,
known as Upper Balch Pit, was a permitted sand/gravel pit from 1962 to 1982;
since 1982, the site has been an upland fill and reclamation site. In 2010, a
wetland reconnaissance technical memorandum documenting no wetlands on
the property was reviewed and approved by the City (City of Renton, File # LUA
10-056, ECF, SP). Field investigations (DP-3, Appendix B) support this
conclusion. While some surface water ponding may occur during wet months,
the site does not meet wetland criteria.
Off-site Wetlands
At least two wetlands appear to be located near the powerline corridor, but
outside of the designated study area on Segment N between SE Cedar Ridge
Drive and the Cedar River. Their approximate locations have been sketched onto
the Critical Area Delineation Maps (Appendix A). These features were not
thoroughly investigated or rated during field work activities, but are mentioned
here because they may have regulated buffers that extend into the project area.
The Watershed Company
May 2016
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Subsequent field work efforts may be needed to address these off-site features if
project impacts are proposed in the vicinity.
3.2 Streams
The streams discussed below have been mapped and classified by the City of
Renton in the City of Renton’s online interactive mapping application (COR
Maps).
Stream MR01 (Honey Dew Creek)
Stream MR01, also known as Honey Dew Creek, is located at the north end of the
study area corridor (Appendix A, Page No. 6). It flows northwest through the
corridor and drains to May Creek located approximately 0.6 mile downstream.
Honey Dew Creek is located in a forested ravine. There are small pockets of
riverine wetland vegetation within the OHWM of the creek. It is approximately
10 feet wide through the study area corridor.
COR Maps classifies Honey Dew Creek as Type F, or fish-bearing, at this
location. Field observations are consistent with this classification.
Stream NR01 (Ginger Creek)
Stream NR01, also known as Ginger Creek, is located east of Wetland NR01
(Appendix A, Page No. 30). Ginger Creek flows generally north through the
study area before draining into the Cedar River, approximately 0.3 mile
downstream. It is mapped by COR Maps as originating southeast of the study
area in Cascade Park. Through the study area, Ginger Creek is located in a very
steep-sided ravine. The bed is made up of coarse cobble and the average width
is approximated at 8 to 10 feet.
COR Maps classifies this stream as Type Np, or non-fish bearing perennial.
During the summer field investigations, no flow was observed in Ginger Creek
in the study area. This is not likely characteristic of the stream, as it was visited
near the end of summer during a drought. The Seattle office of the National
Weather Forecast Office reported drier than normal conditions summer months
in May through July (-1.36 inches departure from normal precipitation). Stream
NR01 should still be classified as Type Np, as Renton Municipal Code specifies
that Type Np waters can include intermittent dry portions of the perennial
channel below the uppermost point of perennial flow during years of non-
normal rainfall. If pole placements are to be placed here, it may be prudent to re-
visit the creek on a non-drought year to assess whether the stream should be re-
typed as Type Ns, or non-fish bearing seasonal.
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Renton Delineation Report
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Stream NR02
Stream NR02 is a seasonal stream that flows north through, or adjacent to, the
study area corridor (Appendix A, Page No. 28, 29 and 30). It crosses or
approaches the corridor at two locations. At the upstream location, it is located
approximately 250 feet east of Ginger Creek, west of the Shadow Hawk
neighborhood. At this location, the stream channel is just beginning to form and
is poorly defined. The channel here was dry and estimated at approximately 2
feet wide. Banks are predominantly vegetated with Himalayan blackberry. The
bed is made up of mostly dirt with some rock and cobble present. An off-site
wetland, located just south of this area, appears to contribute flow to this stream
during wetter months.
Downstream, near the Cedar River Trail, Stream NR02 approaches the study area
corridor again. Here, the stream channel flows in distinct banks and the bed
contains rock and gravel. Average width of the stream at this location is 3 feet.
This portion of the channel was flowing during the site visit.
COR Maps classifies this stream as Type Ns, or non-fish bearing seasonal. Field
observations are consistent with this classification.
Cedar River
While the area immediately adjacent to the Cedar River was specifically
excluded from this study area as described in Methods section above , the Cedar
River is a prominent critical area located in the subject powerline corridor and is
therefore discussed briefly in this section.
The Cedar River is a regulated Shoreline of the State. Aerial photo
measurements indicate that the width of the Cedar River under the powerline
corridor is generally between 70 to 90 feet. Fish use in the Cedar River is well
documented and incudes bull trout, coho salmon, sockeye salmon, Chinook
salmon, steelhead trout, kokanee, and resident cutthroat trout (SalmonScape and
PHS on the Web).
3.3 Wildlife and Habitat
The City of Renton regulates habitats that have a primary association with
species listed by the Federal government or State of Washington as endangered,
threatened, sensitive, and/or local importance as critical areas. The City also
considers areas designated as priority habitats in the Priority Habitat and Species
Program of the Washington State Department of Fish and Wildlife as habitat
conservation areas.
Washington State Priority Habitat and Species (PHS) maps were reviewed for the
project vicinity. In addition to the salmonid species documented in the Cedar
River and Honey Dew Creek, PHS maps depict forested patches adjacent to the
The Watershed Company
May 2016
9
Cedar River as Biodiversity Areas and Corridors. No other PHS features are
mapped in or near the powerline corridor.
Significant wildlife observations were recorded during field investigations. A
pileated woodpecker was in a forested patch near the Honey Dew Creek ravine.
A bald eagle was also observed flying overhead in this general area. More
significantly, an active osprey nest was observed near the study area corridor on
Segment N. The nest was located in a cell tower (Figure 3) southwest of Cedar
Ridge Drive SE. Two adults and one juvenile osprey were visible using the nest
on several occasions during the summer field visits.
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Renton Delineation Report
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Figure 3. Location of osprey nest in the vicinity of Segment N in the City of Renton.
Habitat in the study area is limited to forested patches in topographically low
areas (ravines) associated with Honey Dew Creek and the Cedar River. These
forested areas are typically dominated by deciduous trees including red alder
and bigleaf maple in the canopy. Habitat located in and adjacent to the study
area corridor may have the potential to support regulated wildlife species.
Osprey nest
location
The Watershed Company
May 2016
11
3.4 Critical Area Classifications and Standard Buffers
Critical areas in the City of Renton are regulated in the Renton Municipal Code
(RMC), Title IV Development Regulations, Chapter 3 Environmental Regulations
and Overlay District, 4-3-050 Critical Areas Regulations. Shorelines of the State
in the City of Renton are regulated under the Renton Shoreline Master Program
(RMC 4-3-090).
3.4.1 Wetlands
According to RMC 4-3-050-G.9, wetlands are classified based on the 2014 Rating
System (Hruby). Wetland buffers are measured from the wetland edge and are
based upon the wetland rating, associated habitat score, and impact of land use.
The adjacent land use would not be considered low intensity, therefore the buffer
width for “all other land uses” applies. Wetland NR01 rates as “moderate” for
habitat functions. The following table shows the rating for Wetland NR01 and its
associated standard buffer width.
Table 1. Wetland rating and associated buffer width.
Wetland
Name
2014 Ecology Wetland Rating Category Standard Buffer
Width (ft) Water Quality Hydrology Habitat Total
NR01 5 6 7 18 III 100
Wetland delineations are valid in the City of Renton for up to five years from the
study date of completion. This period may be extended if it can be confirmed
that on-site conditions have not changed.
3.4.2 Streams
Streams are classified based on Washington State’s Permanent Water Typing
System (WAC 222-16-030, RMC 4-3-050-G.7.a). Status as Shoreline of the State,
permanence of flow, and presence of fish or fish habitat are considered to make
the stream class determination. Stream buffers are measured from the ordinary
high water mark (OHWM). Shorelines of the state (Type S streams) are
regulated under the City of Renton SMP (RMC 4-3-090); all other streams are
regulated under RMC 4-3-050 Critical Areas Regulations. A summary of stream
types and buffer widths is provided in Table 2, below.
Table 2. Summary of stream classifications and associated standard buffer widths.
Stream Name Stream Type Standard Buffer Width (ft)
MR01 (Honey Dew Creek) Type F 115
NR01 (Ginger Creek) Type Np 75
NR02 Type Ns 50
Cedar River Type S, Shoreline 100
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Renton Delineation Report
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4 M ITIGATION O PPORTUNITIES
Mitigation opportunities located in the study area were noted during field
investigations. These areas include degraded/disturbed wetland and stream
critical areas and their buffers; all are located under existing powerline corridors.
The degraded and disturbed areas are dominated by invasive species such as
reed canarygrass and Himalayan blackberry. Any proposed revegetation would
need to adhere to vegetation height limits prescribed by PSE standards. Special
care would also need to be given in areas with steep slopes. Locations where
mitigation opportunities exist have been briefly summarized below.
4.1 Segment M (Honey Dew Creek Ravine)
Mitigation opportunities are present in Segment M along the Honey Dew Creek
Ravine (on City of Renton parcels 0423059342 and 0423059035). This site
includes Honey Dew Creek (Stream MR01).
Figure 4. General area (yellow) where mitigation opportunities exist in Segment M
4.2 Segment N (near Talbot Hill Substation)
The area that appears to provide the largest opportunity for mitigation within
the City of Renton is the segment of the corridor between Cedar Ridge Drive SE
The Watershed Company
May 2016
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and the Cedar River trail (private parcels 7701570000 and 7701590000; PSE
parcels 2023059001, 2023059050, and 1623059012; and the City of Renton parcel
2123059003). The site includes portions of Streams NR01 (Ginger Creek), NR02,
Wetland NR01, and critical area buffers.
Figure 5. General area (yellow) where mitigation opportunities along Segment N.
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Renton Delineation Report
14
R EFERENCES
City of Renton. (2015). City of Renton Municipal Code. Retrieved December 31, 2015, from:
http://www.codepublishing.com/WA/Renton/#!/RentonNT.html
City of Renton GIS Department. (2015) City of Renton (COR) Maps. Retrieved from
December 31, 2015, from the City of Renton:
http://rp.rentonwa.gov/SilverlightPublic/Viewer.html?Viewer=COR-Maps
Hruby, T. 2014. Washington State Wetland Rating System for Western Washington: 2014
Update. Publication #14-06-029. Olympia, WA: Washington Department of
Ecology.
Kaufman, F. 2010. Upper Balch Pit Grade & Fill, File No. LUA-10-056, ECF, SP. Office of
the Hearing Examiner, City of Renton.
King County GIS Center. (2015). King County iMap Interactive Mapping Tool.
Retrieved December 31, 2015, from King County GIS Center:
http://www.kingcounty.gov/operations/GIS/Maps/iMAP.aspx
U.S. Army Corps of Engineers (Corps). 2010. Regional Supplement to the Corps of
Engineers Wetland Delineation Manual: Western Washington Mountains,
Valleys, and Coast Region, Version 2.0 (Regional Supplement). Wetlands
Regulatory Assistance Program. U.S. Army Engineer Research and
Development Center, Environmental Laboratory. ERDC/EL TR-10-3.
[USDA] U.S. Department of Agriculture. (2015). Web Soil Survey. Retrieved December 31,
2015, from Natural Resources Conservation Service:
http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx
[USFWS] U.S. Fish and Wildlife Service. (2015). Wetlands Mapper. Retrieved December
31, 2015, from National Wetlands Inventory:
http://www.fws.gov/wetlands/Data/Mapper.html
[WDFW] Washington Department of Fish & Wildlife. (2015). PHS on the Web. Retrieved
December 31, 2015, from Priority Habitats and Species:
http://wdfw.wa.gov/mapping/phs/
[WDFW] Washington Department of Fish & Wildlife. (2015). SalmonScape web
application. Retrieved December 31, 2015, from WDFW:
http://apps.wdfw.wa.gov/salmonscape/
The Watershed Company
May 2016
A PPENDIX A
Critical Area Delineation Maps
King County
Ren ton
M
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM1
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
King County
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM2
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
King County
King County
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM3
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
King County
Rento n
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM4
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
King County
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM5
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M115'STREAM MR01 (Ho ne y C r e e k)
St ream
Critica l Area Bu fferTWC
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM6
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM7
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM8
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM9
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM10
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM11
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM12
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM13
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM14
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM15
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM16
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM17
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM18
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Ren ton
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM19
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM20
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM21
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM22
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM23
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM24
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
M
N
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM/N25
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
N
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTM/N26
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento nN
WETLANDUNNAMED(COR )200'C e d a r River
St ream
Wetland
Critica l Area Bu fferTWC
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN27
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
2. Wetlands shown were
mapped by City of Renton
(2012), but were not
investigated as par t of the PSE
st udy.
WETLANDUNNAMED(COR )
Rento n
N
WETLANDUNNAMED(COR )
50'STREAMNR02St ream
Wetland
Critica l Area Bu fferTWC
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN28
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
2. Wetlands shown were
mapped by City of Renton
(2012), but were not
investigated as par t of the PSE
st udy.
Rento n
N
WETLA NDUNNAMEDSTREAMNR02 St ream
Wetland
Critica l Area Bu fferTWC
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN29
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
N
WETLA NDUNNAMED 50'75'ST R EAM NR02
STREAM NR01(GingerCreek)
St ream
Wetland
Critica l Area Bu fferTWC
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN30
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
2. Obser ved while in the f ield
and sketched, b ut not
delineated.
Rento n
N
DP-1
DP-2
WETLANDNR01
WETLA NDUNNAMED
1 0 0 '
Data PointTWC
Wetland
Critica l Area Bu fferTWC
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN31
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
2. Obser ved while in the f ield
and sketched, b ut not
delineated.
Rento n
N
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN32
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
N
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN33
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento nN
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN34
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
Rento n
N
Existing Pole LocationPSE
100' Screening L imit TWC
City LimitKC
P S E E E 2 3 0 - C R I T I C A L A R E A S A S S E S S M E N T M A P
0 25 50
Fee t
PAG E NO. SEGMENTN35
Da ta sources: Puget Sound Energy, The Watershed Company, and K ing Count y. Aerial im agery from PSE.
Notes:
1. Category IV wet lands that
are less than 2,500 SF in area,
do not have a buffer.
The Watershed Company
May 2016
A PPENDIX B
Wetland Determination Data Forms
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
750 Sixth Street South
Kirkland, Washington 98033
(425) 822-5242
watershedco.com
WETLAND DETERMINATION DATA FORM
Western Mountains, Valleys, and Coast Supplement to the
1987 COE Wetlands Delineation Manual
Project Site: Segment N, parcel number 2123059003 Sampling Date: 7/8/2015
Applicant/Owner: Puget Sound Energy Sampling Point: DP- 1
Investigator: Katy Crandall, Rose Whitson City/County: Renton
Sect., Township, Range: S 16 T 23 R 05 State: WA
Landform (hillslope, terrace, etc): Hillslope
Slope (%): ~5 Local relief (concave, convex, none): Concave
Subregion (LRR): A Lat: Long: Datum:
Soil Map Unit Name: AgC – Alderwood gravelly sandy loam, 8-15% slopes NWI classification: NA
Are climatic/hydrologic conditions on the site typical for this time of year? ☐ Yes ☒ No (If no, explain in remarks.)
Are “Normal Circumstances” present on the site? ☒ Yes ☐ No
(If needed, explain any answers in Remarks.) Are Vegetation☐, Soil ☐, or Hydrology ☐ significantly disturbed?
Are Vegetation☐, Soil ☐, or Hydrology ☐ naturally problematic
SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc.
Hydrophytic Vegetation Present? Yes ☒ No ☐
Is the Sampling Point within a Wetland? Yes ☒ No ☐ Hydric Soils Present? Yes ☒ No ☐
Wetland Hydrology Present? Yes ☒ No ☐
Remarks: Wetland NR01
VEGETATION – Use scientific names of plants.
Tree Stratum (Plot size: 5m diam.) Absolute %
Cover
Dominant
Species?
Indicator
Status
Dominance Test Worksheet
1. Number of Dominant Species
that are OBL, FACW, or FAC: 2 (A) 2.
3. Total Number of Dominant
Species Across All Strata: 2 (B) 4.
= Total Cover Percent of Dominant Species
that are OBL, FACW, or FAC: 100 (A/B)
Sapling/Shrub Stratum (Plot size: 3m diam.)
1. Spiraea douglasii 15 Y FACW Prevalence Index Worksheet
2. Total % Cover of Multiply by
3. OBL species x 1 =
4. FACW species x 2 =
5. FAC species x 3 =
15 = Total Cover FACU species x 4 =
UPL species x 5 =
Herb Stratum (Plot size: 1m diam.) Column totals (A) (B)
1. Phalaris arundinacea 95 Y FACW
2. Prevalence Index = B / A =
3.
4. Hydrophytic Vegetation Indicators
5. ☒ Dominance test is > 50%
6. ☐ Prevalence test is ≤ 3.0 *
7. Morphological Adaptations * (provide supporting
8. ☐ data in remarks or on a separate sheet)
9. ☐ Wetland Non-Vascular Plants *
10. ☐ Problematic Hydrophytic Vegetation * (explain)
11.
95 = Total Cover * Indicators of hydric soil and wetland hydrology must be
present, unless disturbed or problematic
Woody Vine Stratum (Plot size: )
Hydrophytic Vegetation
Present? Yes ☒ No ☐
1.
2.
= Total Cover
% Bare Ground in Herb Stratum:
Remarks:
DP- 1
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
SOIL Sampling Point – DP-1
HYDROLOGY
Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.)
Depth Matrix Redox Features
(inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks
0-12 5 YR 3/1 97 5 YR 3/4 3 C M Gravelly loam
1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains 2Loc: PL=Pore Lining, M=Matrix
Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3
☐ Histosol (A1) ☐ Sandy Redox (S5) ☐ 2cm Muck (A10)
☐ Histic Epipedon (A2) ☐ Stripped Matrix (S6) ☐ Red Parent Material (TF2)
☐ Black Histic (A3) ☐ Loamy Mucky Mineral (F1) (except MLRA 1) ☐ Other (explain in remarks)
☐ Hydrogen Sulfide (A4) ☐ Loamy Gleyed Matrix (F2) ☐
☐ Depleted Below Dark Surface (A11) ☐ Depleted Matrix (F3)
☐ Thick Dark Surface (A12) ☒ Redox Dark Surface (F6) 3 Indicators of hydrophytic vegetation and wetland hydrology must
be present, unless disturbed or problematic ☐ Sandy Mucky Mineral (S1) ☐ Depleted Dark Surface (F7)
☐ Sandy Gleyed Matrix (S4) ☐ Redox Depressions (F8)
Restrictive Layer (if present):
Hydric soil present? Yes ☒ No ☐ Type: ________________________________________
Depth (inches): _____________________________________
Remarks:
Wetland Hydrology Indicators:
Primary Indicators (minimum of one required: check all that apply): Secondary Indicators (2 or more required):
☐ Surface water (A1) ☐ Sparsely Vegetated Concave Surface (B8) ☐ Water-Stained Leaves (B9) (MLRA 1, 2, 4A & 4B)
☐ High Water Table (A2) ☐ Water-Stained Leaves (except MLRA 1, 2, 4A & 4B) (B9) ☐ Drainage Patterns (B10)
☐ Saturation (A3) ☐ Salt Crust (B11) ☐ Dry-Season Water Table (C2)
☐ Water Marks (B1) ☐ Aquatic Invertebrates (B13) ☐ Saturation Visible on Aerial Imagery (C9)
☐ Sediment Deposits (B2) ☐ Hydrogen Sulfide Odor (C1) ☒ Geomorphic Position (D2)
☐ Drift Deposits (B3) ☐ Oxidized Rhizospheres along Living Roots (C3) ☐ Shallow Aquitard (D3)
☐ Algal Mat or Crust (B4) ☐ Presence of Reduced Iron (C4) ☒ FAC-Neutral Test (D5)
☐ Iron Deposits (B5) ☐ Recent Iron Reduction in Tilled Soils (C6) ☐ Raised Ant Mounds (D6) (LRR A)
☐ Surface Soil Cracks (B6) ☐ Stunted or Stressed Plants (D1) (LRR A) ☐ Frost-Heave Hummocks
☐ Inundation Visible on Aerial Imagery
(B7) ☐ Other (explain in remarks)
Field Observations
Wetland Hydrology Present? Yes ☒ No ☐
Surface Water Present? Yes ☐ No ☒ Depth (in):
Water Table Present? Yes ☐ No ☒ Depth (in):
Saturation Present?
(includes capillary fringe) Yes ☐ No ☒ Depth (in):
Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available:
Remarks: Less than average rainfall.
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
750 Sixth Street South
Kirkland, Washington 98033
(425) 822-5242
watershedco.com
WETLAND DETERMINATION DATA FORM
Western Mountains, Valleys, and Coast Supplement to the
1987 COE Wetlands Delineation Manual
Project Site: Segment N, parcel number 2123059003 Sampling Date: 7/8/2015
Applicant/Owner: Puget Sound Energy Sampling Point: DP- 2
Investigator: Katy Crandall, Rose Whitson City/County: Renton
Sect., Township, Range: S 16 T 23 R 05 State: WA
Landform (hillslope, terrace, etc): Hillslope, hummocky
Slope (%): 2 Local relief (concave, convex, none): Concave
Subregion (LRR): A Lat: Long: Datum:
Soil Map Unit Name: AgC – Alderwood gravelly sandy loam, 8-15% slopes NWI classification: NA
Are climatic/hydrologic conditions on the site typical for this time of year? ☐ Yes ☒ No (If no, explain in remarks.)
Are “Normal Circumstances” present on the site? ☒ Yes ☐ No
(If needed, explain any answers in Remarks.) Are Vegetation☐, Soil ☐, or Hydrology ☐ significantly disturbed?
Are Vegetation☐, Soil ☐, or Hydrology ☐ naturally problematic
SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc.
Hydrophytic Vegetation Present? Yes ☐ No ☒
Is the Sampling Point within a Wetland? Yes ☐ No ☒ Hydric Soils Present? Yes ☒ No ☐
Wetland Hydrology Present? Yes ☐ No ☒
Remarks: Out-pit near wetland NR01.
VEGETATION – Use scientific names of plants.
Tree Stratum (Plot size: 5m diam.) Absolute %
Cover
Dominant
Species?
Indicator
Status
Dominance Test Worksheet
1. Number of Dominant Species
that are OBL, FACW, or FAC: 1 (A) 2.
3. Total Number of Dominant
Species Across All Strata: 4 (B) 4.
= Total Cover Percent of Dominant Species
that are OBL, FACW, or FAC: 25 (A/B)
Sapling/Shrub Stratum (Plot size: 3m diam.)
1. Spiraea douglasii 40 Y FACW Prevalence Index Worksheet
2. Total % Cover of Multiply by
3. OBL species x 1 =
4. FACW species x 2 =
5. FAC species x 3 =
40 = Total Cover FACU species x 4 =
UPL species x 5 =
Herb Stratum (Plot size: 1m diam.) Column totals (A) (B)
1. Gaultheria shallon 75 Y FACU
2. Pteridium aquilinum 15 Y FACU Prevalence Index = B / A =
3.
4. Hydrophytic Vegetation Indicators
5. ☐ Dominance test is > 50%
6. ☐ Prevalence test is ≤ 3.0 *
7. Morphological Adaptations * (provide supporting
8. ☐ data in remarks or on a separate sheet)
9. ☐ Wetland Non-Vascular Plants *
10. ☐ Problematic Hydrophytic Vegetation * (explain)
11.
90 = Total Cover * Indicators of hydric soil and wetland hydrology must be
present, unless disturbed or problematic
Woody Vine Stratum (Plot size: )
Hydrophytic Vegetation
Present? Yes ☐ No ☒
1. Rubus armeniacus 20 Y FACU
2.
= Total Cover
% Bare Ground in Herb Stratum:
Remarks:
DP- 2
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
SOIL Sampling Point – DP-2
HYDROLOGY
Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.)
Depth Matrix Redox Features
(inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks
0-6 10YR 2/2 100 Loam
6-12 7.5YR 4/2 80 5YR 4/6 20 C M Gravelly loam
1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains 2Loc: PL=Pore Lining, M=Matrix
Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3
☐ Histosol (A1) ☐ Sandy Redox (S5) ☐ 2cm Muck (A10)
☐ Histic Epipedon (A2) ☐ Stripped Matrix (S6) ☐ Red Parent Material (TF2)
☐ Black Histic (A3) ☐ Loamy Mucky Mineral (F1) (except MLRA 1) ☐ Other (explain in remarks)
☐ Hydrogen Sulfide (A4) ☐ Loamy Gleyed Matrix (F2) ☐
☐ Depleted Below Dark Surface (A11) ☒ Depleted Matrix (F3)
☐ Thick Dark Surface (A12) ☐ Redox Dark Surface (F6) 3 Indicators of hydrophytic vegetation and wetland hydrology must
be present, unless disturbed or problematic ☐ Sandy Mucky Mineral (S1) ☐ Depleted Dark Surface (F7)
☐ Sandy Gleyed Matrix (S4) ☐ Redox Depressions (F8)
Restrictive Layer (if present):
Hydric soil present? Yes ☒ No ☐ Type: ________________________________________
Depth (inches): _____________________________________
Remarks:
Wetland Hydrology Indicators:
Primary Indicators (minimum of one required: check all that apply): Secondary Indicators (2 or more required):
☐ Surface water (A1) ☐ Sparsely Vegetated Concave Surface (B8) ☐ Water-Stained Leaves (B9) (MLRA 1, 2, 4A & 4B)
☐ High Water Table (A2) ☐ Water-Stained Leaves (except MLRA 1, 2, 4A & 4B) (B9) ☐ Drainage Patterns (B10)
☐ Saturation (A3) ☐ Salt Crust (B11) ☐ Dry-Season Water Table (C2)
☐ Water Marks (B1) ☐ Aquatic Invertebrates (B13) ☐ Saturation Visible on Aerial Imagery (C9)
☐ Sediment Deposits (B2) ☐ Hydrogen Sulfide Odor (C1) ☐ Geomorphic Position (D2)
☐ Drift Deposits (B3) ☐ Oxidized Rhizospheres along Living Roots (C3) ☐ Shallow Aquitard (D3)
☐ Algal Mat or Crust (B4) ☐ Presence of Reduced Iron (C4) ☐ FAC-Neutral Test (D5)
☐ Iron Deposits (B5) ☐ Recent Iron Reduction in Tilled Soils (C6) ☐ Raised Ant Mounds (D6) (LRR A)
☐ Surface Soil Cracks (B6) ☐ Stunted or Stressed Plants (D1) (LRR A) ☐ Frost-Heave Hummocks
☐ Inundation Visible on Aerial Imagery
(B7) ☐ Other (explain in remarks)
Field Observations
Wetland Hydrology Present? Yes ☐ No ☒
Surface Water Present? Yes ☐ No ☒ Depth (in):
Water Table Present? Yes ☐ No ☒ Depth (in):
Saturation Present?
(includes capillary fringe) Yes ☐ No ☒ Depth (in):
Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available:
Remarks: Less than average rainfall.
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
750 Sixth Street South
Kirkland, Washington 98033
(425) 822-5242
watershedco.com
WETLAND DETERMINATION DATA FORM
Western Mountains, Valleys, and Coast Supplement to the
1987 COE Wetlands Delineation Manual
Project Site: Segment M, parcel number 1623059059 Sampling Date: 5/22/2015
Applicant/Owner: Puget Sound Energy Sampling Point: DP- 3
Investigator: Katy Crandall, Mike Foster, Ryan Kahlo City/County: Renton
Sect., Township, Range: S 16 T 23 R 05 State: WA
Landform (hillslope, terrace, etc): Depression
Slope (%): <5 Local relief (concave, convex, none): Concave
Subregion (LRR): A Lat: Long: Datum:
Soil Map Unit Name: An – Arents, Everett material NWI classification: PABFh
Are climatic/hydrologic conditions on the site typical for this time of year? ☒ Yes ☐ No (If no, explain in remarks.)
Are “Normal Circumstances” present on the site? ☒ Yes ☐ No
(If needed, explain any answers in Remarks.) Are Vegetation☐, Soil ☐, or Hydrology ☐ significantly disturbed?
Are Vegetation☐, Soil ☐, or Hydrology ☐ naturally problematic
SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc.
Hydrophytic Vegetation Present? Yes ☒ No ☐
Is the Sampling Point within a Wetland? Yes ☐ No ☒ Hydric Soils Present? Yes ☐ No ☒
Wetland Hydrology Present? Yes ☒ No ☐
Remarks: Low area on Segale property; area appears to have been disturbed in the past. Mix of wetland and non-wetland vegetation
near DP.
VEGETATION – Use scientific names of plants.
Tree Stratum (Plot size: 5m diam.) Absolute %
Cover
Dominant
Species?
Indicator
Status
Dominance Test Worksheet
1. Number of Dominant Species
that are OBL, FACW, or FAC: 3 (A) 2.
3. Total Number of Dominant
Species Across All Strata: 3 (B) 4.
= Total Cover Percent of Dominant Species
that are OBL, FACW, or FAC: 100 (A/B)
Sapling/Shrub Stratum (Plot size: 3m diam.)
1. Populus balsamifera 30 Y FAC Prevalence Index Worksheet
2. Salix lucida 20 Y FACW Total % Cover of Multiply by
3. OBL species x 1 =
4. FACW species x 2 =
5. FAC species x 3 =
50 = Total Cover FACU species x 4 =
UPL species x 5 =
Herb Stratum (Plot size: 1m diam.) Column totals (A) (B)
1. Juncus effusus 70 Y FACW
2. Achillea millefolium 10 N FACU Prevalence Index = B / A =
3. Phalaris arundinacea 5 N FACW
4. Cirsium arvense 5 N FAC Hydrophytic Vegetation Indicators
5. Carex stipata 3 N OBL ☐ Dominance test is > 50%
6. ☐ Prevalence test is ≤ 3.0 *
7. Morphological Adaptations * (provide supporting
8. ☐ data in remarks or on a separate sheet)
9. ☐ Wetland Non-Vascular Plants *
10. ☐ Problematic Hydrophytic Vegetation * (explain)
11.
93 = Total Cover * Indicators of hydric soil and wetland hydrology must be
present, unless disturbed or problematic
Woody Vine Stratum (Plot size: )
Hydrophytic Vegetation
Present? Yes ☒ No ☐
1.
2.
= Total Cover
% Bare Ground in Herb Stratum:
Remarks:
DP- 3
US Army Corps of Engineers Western Mountains, Valleys, and Coast – Interim Version
SOIL Sampling Point – DP-3
HYDROLOGY
Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.)
Depth Matrix Redox Features
(inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks
0-12 10YR 4/2 99 10YR 4/4 1 C M Gravelly sandy loam
1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains 2Loc: PL=Pore Lining, M=Matrix
Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3
☐ Histosol (A1) ☐ Sandy Redox (S5) ☐ 2cm Muck (A10)
☐ Histic Epipedon (A2) ☐ Stripped Matrix (S6) ☐ Red Parent Material (TF2)
☐ Black Histic (A3) ☐ Loamy Mucky Mineral (F1) (except MLRA 1) ☐ Other (explain in remarks)
☐ Hydrogen Sulfide (A4) ☐ Loamy Gleyed Matrix (F2) ☐
☐ Depleted Below Dark Surface (A11) ☐ Depleted Matrix (F3)
☐ Thick Dark Surface (A12) ☐ Redox Dark Surface (F6) 3 Indicators of hydrophytic vegetation and wetland hydrology must
be present, unless disturbed or problematic ☐ Sandy Mucky Mineral (S1) ☐ Depleted Dark Surface (F7)
☐ Sandy Gleyed Matrix (S4) ☐ Redox Depressions (F8)
Restrictive Layer (if present):
Hydric soil present? Yes ☐ No ☒ Type: ________________________________________
Depth (inches): _____________________________________
Remarks:
Wetland Hydrology Indicators:
Primary Indicators (minimum of one required: check all that apply): Secondary Indicators (2 or more required):
☐ Surface water (A1) ☐ Sparsely Vegetated Concave Surface (B8) ☐ Water-Stained Leaves (B9) (MLRA 1, 2, 4A & 4B)
☐ High Water Table (A2) ☐ Water-Stained Leaves (except MLRA 1, 2, 4A & 4B) (B9) ☐ Drainage Patterns (B10)
☐ Saturation (A3) ☐ Salt Crust (B11) ☐ Dry-Season Water Table (C2)
☐ Water Marks (B1) ☐ Aquatic Invertebrates (B13) ☐ Saturation Visible on Aerial Imagery (C9)
☐ Sediment Deposits (B2) ☐ Hydrogen Sulfide Odor (C1) ☒ Geomorphic Position (D2)
☐ Drift Deposits (B3) ☐ Oxidized Rhizospheres along Living Roots (C3) ☐ Shallow Aquitard (D3)
☐ Algal Mat or Crust (B4) ☐ Presence of Reduced Iron (C4) ☒ FAC-Neutral Test (D5)
☐ Iron Deposits (B5) ☐ Recent Iron Reduction in Tilled Soils (C6) ☐ Raised Ant Mounds (D6) (LRR A)
☐ Surface Soil Cracks (B6) ☐ Stunted or Stressed Plants (D1) (LRR A) ☐ Frost-Heave Hummocks
☐ Inundation Visible on Aerial Imagery
(B7) ☐ Other (explain in remarks)
Field Observations
Wetland Hydrology Present? Yes ☒ No ☐
Surface Water Present? Yes ☐ No ☒ Depth (in):
Water Table Present? Yes ☐ No ☒ Depth (in):
Saturation Present?
(includes capillary fringe) Yes ☐ No ☒ Depth (in):
Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available:
Remarks: Damp low in soil profile; not saturated
The Watershed Company
May 2016
A PPENDIX C
Wetland Rating Forms
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 1
RATING SUMMARY – Western Washington
Name of wetland (or ID #): Wetland NR01 Date of site visit: 7/8/2014
Rated by: Trained by Ecology? ☒Y ☐N Date of training: 09/2014
HGM Class used for rating: Slope Wetland has multiple HGM classes? ☐Y ☒N
NOTE: Form is not complete without the figures requested (figures can be combined).
Source of base aerial photo/map: City of Renton online mapping application (COR Maps)
OVERALL WETLAND CATEGORY (based on functions ☒ or special characteristics ☐)
1. Category of wetland based on FUNCTIONS
☐ Category I – Total score = 23 - 27
☐ Category II – Total score = 20 - 22
☒ Category III – Total score = 16 - 19
☐ Category IV – Total score = 9 - 15
FUNCTION Improving
Water Quality
Hydrologic Habitat
Circle the appropriate ratings
Site Potential H M L H M L H M L
Landscape Potential H M L H M L H M L
Value H M L H M L H M L TOTAL
Score Based on
Ratings 5 6 7 18
2. Category based on SPECIAL CHARACTERISTICS of wetland
CHARACTERISTIC CATEGORY
Estuarine I II
Wetland of High Conservation Value I
Bog I
Mature Forest I
Old Growth Forest I
Coastal Lagoon I II
Interdunal I II III IV
None of the above ☒
Score for each function based on three ratings (order of ratings is not important)
9 = H,H,H
8 = H,H,M
7 = H,H,L
7 = H,M,M
6 = H,M,L
6 = M,M,M
5 = H,L,L
5 = M,M,L
4 = M,L,L
3 = L,L,L
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 2
Maps and figures required to answer questions correctly for
Western Washington
Depressional Wetlands
Map of: To answer questions: Figure #
Cowardin plant classes D 1.3, H 1.1, H 1.4
Hydroperiods D 1.4, H 1.2
Location of outlet (can be added to map of hydroperiods) D 1.1, D 4.1
Boundary of area within 150 ft of the wetland (can be added to another figure) D 2.2, D 5.2
Map of the contributing basin D 4.3, D 5.3
1 km Polygon: Area that extends 1 km from entire wetland edge - including
polygons for accessible habitat and undisturbed habitat
H 2.1, H 2.2, H 2.3
Screen capture of map of 303(d) listed waters in basin (from Ecology website) D 3.1, D 3.2
Screen capture of list of TMDLs for WRIA in which unit is found (from web) D 3.3
Riverine Wetlands
Map of: To answer questions: Figure #
Cowardin plant classes H 1.1, H 1.4
Hydroperiods H 1.2
Ponded depressions R 1.1
Boundary of area within 150 ft of the wetland (can be added to another figure) R 2.4
Plant cover of trees, shrubs, and herbaceous plants R 1.2, R 4.2
Width of unit vs. width of stream (can be added to another figure) R 4.1
Map of the contributing basin R 2.2, R 2.3, R 5.2
1 km Polygon: Area that extends 1 km from entire wetland edge - including
polygons for accessible habitat and undisturbed habitat
H 2.1, H 2.2, H 2.3
Screen capture of map of 303(d) listed waters in basin (from Ecology website) R 3.1
Screen capture of list of TMDLs for WRIA in which unit is found (from web) R 3.2, R 3.3
Lake Fringe Wetlands
Map of: To answer questions: Figure #
Cowardin plant classes L 1.1, L 4.1, H 1.1, H 1.4
Plant cover of trees, shrubs, and herbaceous plants L 1.2
Boundary of area within 150 ft of the wetland (can be added to another figure) L 2.2
1 km Polygon: Area that extends 1 km from entire wetland edge - including
polygons for accessible habitat and undisturbed habitat
H 2.1, H 2.2, H 2.3
Screen capture of map of 303(d) listed waters in basin (from Ecology website) L 3.1, L 3.2
Screen capture of list of TMDLs for WRIA in which unit is found (from web) L 3.3
Slope Wetlands
Map of: To answer questions: Figure #
Cowardin plant classes H 1.1, H 1.4
Hydroperiods H 1.2
Plant cover of dense trees, shrubs, and herbaceous plants S 1.3
Plant cover of dense, rigid trees, shrubs, and herbaceous plants
(can be added to figure above)
S 4.1
Boundary of 150 ft buffer (can be added to another figure) S 2.1, S 5.1
1 km Polygon: Area that extends 1 km from entire wetland edge - including
polygons for accessible habitat and undisturbed habitat
H 2.1, H 2.2, H 2.3
Screen capture of map of 303(d) listed waters in basin (from Ecology website) S 3.1, S 3.2
Screen capture of list of TMDLs for WRIA in which unit is found (from web) S 3.3
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 3
HGM Classification of Wetlands in Western Washington
1. Are the water levels in the entire unit usually controlled by tides except during floods?
☒NO – go to 2 ☐YES – the wetland class is Tidal Fringe – go to 1.1 1.1 Is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)?
NO – Saltwater Tidal Fringe (Estuarine) YES – Freshwater Tidal Fringe
If your wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands. If it
is Saltwater Tidal Fringe it is an Estuarine wetland and is not scored. This method cannot be used to
score functions for estuarine wetlands. 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Groundwater and surface water runoff are NOT sources of water to the unit.
☒NO – go to 3 ☐YES – The wetland class is Flats
If your wetland can be classified as a Flats wetland, use the form for Depressional wetlands. 3. Does the entire wetland unit meet all of the following criteria?
☐The vegetated part of the wetland is on the shores of a body of permanent open water (without any plants on the surface at any time of the year) at least 20 ac (8 ha) in size;
☐At least 30% of the open water area is deeper than 6.6 ft (2 m).
☒NO – go to 4 ☐YES – The wetland class is Lake Fringe (Lacustrine Fringe) 4. Does the entire wetland unit meet all of the following criteria?
☒The wetland is on a slope (slope can be very gradual),
☒The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without distinct banks,
☒The water leaves the wetland without being impounded.
☐NO – go to 5 ☒YES – The wetland class is Slope
NOTE: Surface water does not pond in these type of wetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3 ft diameter and less than 1 ft deep). 5. Does the entire wetland unit meet all of the following criteria?
☐The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river,
☐The overbank flooding occurs at least once every 2 years.
For questions 1-7, the criteria described must apply to the entire unit being rated. If the hydrologic criteria listed in each question do not apply to the entire unit being rated, you probably have a unit with multiple HGM classes. In this case, identify which hydrologic criteria in questions 1-7 apply, and go to Question 8.
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 4
☐NO – go to 6 ☐YES – The wetland class is Riverine
NOTE: The Riverine unit can contain depressions that are filled with water when the river is not flooding 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at some time during the year? This means that any outlet, if present, is higher than the interior
of the wetland.
☐NO – go to 7 ☐YES – The wetland class is Depressional 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding? The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet.
☐NO – go to 8 ☐YES – The wetland class is Depressional
8. Your wetland unit seems to be difficult to classify and probably contains several different HGM classes. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a Depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present within the wetland unit being scored.
NOTE: Use this table only if the class that is recommended in the second column represents 10% or more of the total area of the wetland unit being rated. If the area of the HGM class listed in column 2 is less than 10% of the unit; classify the wetland using the class that represents more than 90% of the total area.
HGM classes within the wetland unit
being rated
HGM class to
use in rating
Slope + Riverine Riverine
Slope + Depressional Depressional
Slope + Lake Fringe Lake Fringe
Depressional + Riverine along stream
within boundary of depression
Depressional
Depressional + Lake Fringe Depressional
Riverine + Lake Fringe Riverine
Salt Water Tidal Fringe and any other
class of freshwater wetland
Treat as
ESTUARINE
If you are still unable to determine which of the above criteria apply to your wetland, or if you have
more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the
rating.
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 11
SLOPE WETLANDS
Water Quality Functions - Indicators that the site functions to improve water quality
S 1.0. Does the site have the potential to improve water quality?
S 1.1. Characteristics of the average slope of the wetland: (a 1% slope has a 1 ft vertical drop in elevation for every
100 ft of horizontal distance)
Slope is 1% or less points = 3
Slope is > 1%-2% points = 2
Slope is > 2%-5% points = 1
Slope is greater than 5% points = 0
1
S 1.2. The soil 2 in below the surface (or duff layer) is true clay or true organic (use NRCS definitions): Yes = 3 No = 0 0
S 1.3. Characteristics of the plants in the wetland that trap sediments and pollutants:
Choose the points appropriate for the description that best fits the plants in the wetland. Dense means you
have trouble seeing the soil surface (>75% cover), and uncut means not grazed or mowed and plants are higher
than 6 in.
Dense, uncut, herbaceous plants > 90% of the wetland area points = 6
Dense, uncut, herbaceous plants > ½ of area points = 3
Dense, woody, plants > ½ of area points = 2
Dense, uncut, herbaceous plants > ¼ of area points = 1
Does not meet any of the criteria above for plants points = 0
6
Total for S 1 Add the points in the boxes above 7
Rating of Site Potential If score is: ☐12 = H ☒6-11 = M ☐0-5 = L Record the rating on the first page
S 2.0. Does the landscape have the potential to support the water quality function of the site?
S 2.1. Is > 10% of the area within 150 ft on the uphill side of the wetland in land uses that generate pollutants?
Yes = 1 No = 0 0
S 2.2. Are there other sources of pollutants coming into the wetland that are not listed in question S 2.1?
Other sources Yes = 1 No = 0 0
Total for S 2 Add the points in the boxes above 0
Rating of Landscape Potential If score is: ☐1-2 = M ☒0 = L Record the rating on the first page
S 3.0. Is the water quality improvement provided by the site valuable to society?
S 3.1. Does the wetland discharge directly (i.e., within 1 mi) to a stream, river, lake, or marine water that is on the
303(d) list? Yes = 1 No = 0 0
S 3.2. Is the wetland in a basin or sub-basin where water quality is an issue? At least one aquatic resource in the basin is
on the 303(d) list. Yes = 1 No = 0 1
S 3.3. Has the site been identified in a watershed or local plan as important for maintaining water quality? Answer YES
if there is a TMDL for the basin in which unit is found. Yes = 2 No = 0 0
Total for S 3 Add the points in the boxes above 1
Rating of Value If score is: ☐2-4 = H ☒1 = M ☐0 = L Record the rating on the first page
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 12
SLOPE WETLANDS
Hydrologic Functions - Indicators that the site functions to reduce flooding and stream erosion
S 4.0. Does the site have the potential to reduce flooding and stream erosion?
S 4.1. Characteristics of plants that reduce the velocity of surface flows during storms: Choose the points appropriate
for the description that best fits conditions in the wetland. Stems of plants should be thick enough (usually >1/8 8 in), or dense enough, to remain erect during surface flows.
Dense, uncut, rigid plants cover > 90% of the area of the wetland points = 1
All other conditions points = 0
1
Rating of Site Potential If score is: ☒1 = M ☐0 = L Record the rating on the first page
S 5.0. Does the landscape have the potential to support the hydrologic functions of the site?
S 5.1. Is more than 25% of the area within 150 ft upslope of wetland in land uses or cover that generate excess
surface runoff? Yes = 1 No = 0 0
Rating of Landscape Potential If score is: ☐1 = M ☒0 = L Record the rating on the first page
S 6.0. Are the hydrologic functions provided by the site valuable to society?
S 6.1. Distance to the nearest areas downstream that have flooding problems:
The sub-basin immediately down-gradient of site has flooding problems that result in damage to human or
natural resources (e.g., houses or salmon redds) points = 2
Surface flooding problems are in a sub-basin farther down-gradient points = 1
No flooding problems anywhere downstream points = 0
2
S 6.2. Has the site been identified as important for flood storage or flood conveyance in a regional flood control plan?
Yes = 2 No = 0 0
Total for S 6 Add the points in the boxes above 2
Rating of Value If score is: ☒2-4 = H ☐1 = M ☐0 = L Record the rating on the first page
NOTES and FIELD OBSERVATIONS:
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 13
These questions apply to wetlands of all HGM classes.
HABITAT FUNCTIONS - Indicators that site functions to provide important habitat
H 1.0. Does the site have the potential to provide habitat?
H 1.1. Structure of plant community: Indicators are Cowardin classes and strata within the Forested class. Check the
Cowardin plant classes in the wetland. Up to 10 patches may be combined for each class to meet the threshold
of ¼ ac or more than 10% of the unit if it is smaller than 2.5 ac. Add the number of structures checked.
☐ Aquatic bed 4 structures or more: points = 4
☒ Emergent 3 structures: points = 2
☒ Scrub-shrub (areas where shrubs have > 30% cover) 2 structures: points = 1
☐ Forested (areas where trees have > 30% cover) 1 structure: points = 0
If the unit has a Forested class, check if:
☐ The Forested class has 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover)
that each cover 20% within the Forested polygon
1
H 1.2. Hydroperiods
Check the types of water regimes (hydroperiods) present within the wetland. The water regime has to cover
more than 10% of the wetland or ¼ ac to count (see text for descriptions of hydroperiods).
☐ Permanently flooded or inundated 4 or more types present: points = 3
☐ Seasonally flooded or inundated 3 types present: points = 2
☒ Occasionally flooded or inundated 2 types present: points = 1
☒ Saturated only 1 type present: points = 0
☐ Permanently flowing stream or river in, or adjacent to, the wetland
☐ Seasonally flowing stream in, or adjacent to, the wetland
☐ Lake Fringe wetland 2 points
☐ Freshwater tidal wetland 2 points
1
H 1.3. Richness of plant species
Count the number of plant species in the wetland that cover at least 10 ft2.
Different patches of the same species can be combined to meet the size threshold and you do not have to name
the species. Do not include Eurasian milfoil, reed canarygrass, purple loosestrife, Canadian thistle
If you counted: > 19 species points = 2
5 - 19 species points = 1
< 5 species points = 0
1
H 1.4. Interspersion of habitats
Decide from the diagrams below whether interspersion among Cowardin plants classes (described in H 1.1), or
the classes and unvegetated areas (can include open water or mudflats) is high, moderate, low, or none. If you
have four or more plant classes or three classes and open water, the rating is always high.
None = 0 points Low = 1 point Moderate = 2 points
All three diagrams
in this row
are HIGH = 3points
1
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 14
H 1.5. Special habitat features:
Check the habitat features that are present in the wetland. The number of checks is the number of points.
☐ Large, downed, woody debris within the wetland (> 4 in diameter and 6 ft long).
☐ Standing snags (dbh > 4 in) within the wetland
☐ Undercut banks are present for at least 6.6 ft (2 m) and/or overhanging plants extends at least 3.3 ft (1 m)
over a stream (or ditch) in, or contiguous with the wetland, for at least 33 ft (10 m)
☐ Stable steep banks of fine material that might be used by beaver or muskrat for denning (> 30 degree
slope) OR signs of recent beaver activity are present (cut shrubs or trees that have not yet weathered
where wood is exposed)
☐ At least ¼ ac of thin-stemmed persistent plants or woody branches are present in areas that are
permanently or seasonally inundated (structures for egg-laying by amphibians)
☐ Invasive plants cover less than 25% of the wetland area in every stratum of plants (see H 1.1 for list of
strata)
0
Total for H 1 Add the points in the boxes above 4
Rating of Site Potential If score is: ☐15-18 = H ☐7-14 = M ☒0-6 = L Record the rating on the first page
H 2.0. Does the landscape have the potential to support the habitat functions of the site?
H 2.1. Accessible habitat (include only habitat that directly abuts wetland unit).
Calculate: % undisturbed habitat: 0 + [(40% moderate and low intensity land uses)/2]: 20 = 20% If total
accessible habitat is:
> 1/3 (33.3%) of 1 km Polygon points = 3
20-33% of 1 km Polygon points = 2
10-19% of 1 km Polygon points = 1
< 10% of 1 km Polygon points = 0
2
H 2.2. Undisturbed habitat in 1 km Polygon around the wetland.
Calculate: % undisturbed habitat: 20 + [(50% moderate and low intensity land uses)/2]: 25 = 45%
Undisturbed habitat > 50% of Polygon points = 3
Undisturbed habitat 10-50% and in 1-3 patches points = 2
Undisturbed habitat 10-50% and > 3 patches points = 1
Undisturbed habitat < 10% of 1 km Polygon points = 0
2
H 2.3. Land use intensity in 1 km Polygon: If
> 50% of 1 km Polygon is high intensity land use points = (- 2)
≤ 50% of 1 km Polygon is high intensity points = 0
0
Total for H 2 Add the points in the boxes above 4
Rating of Landscape Potential If score is: ☒4-6 = H ☐1-3 = M ☐< 1 = L Record the rating on the first page
H 3.0. Is the habitat provided by the site valuable to society?
H 3.1. Does the site provide habitat for species valued in laws, regulations, or policies? Choose only the highest score
that applies to the wetland being rated.
Site meets ANY of the following criteria: points = 2
☒ It has 3 or more priority habitats within 100 m (see next page)
☐ It provides habitat for Threatened or Endangered species (any plant or animal on the state or federal lists)
☐ It is mapped as a location for an individual WDFW priority species
☐ It is a Wetland of High Conservation Value as determined by the Department of Natural Resources
☐ It has been categorized as an important habitat site in a local or regional comprehensive plan,
in a Shoreline Master Plan, or in a watershed plan
Site has 1 or 2 priority habitats (listed on next page) within 100 m points = 1
Site does not meet any of the criteria above points = 0
2
Rating of Value If score is: ☒2 = H ☐1 = M ☐0 = L Record the rating on the first page
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 15
WDFW Priority Habitats Priority habitats listed by WDFW (see complete descriptions of WDFW priority habitats, and the counties in which they can be found, in: Washington Department of Fish and Wildlife. 2008. Priority Habitat and Species List. Olympia, Washington. 177 pp. http://wdfw.wa.gov/publications/00165/wdfw00165.pdf or access the list from here: http://wdfw.wa.gov/conservation/phs/list/) Count how many of the following priority habitats are within 330 ft (100 m) of the wetland unit: NOTE: This question is
independent of the land use between the wetland unit and the priority habitat.
☐ Aspen Stands: Pure or mixed stands of aspen greater than 1 ac (0.4 ha).
☒ Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions in WDFW PHS report).
☐ Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock.
☐ Old-growth/Mature forests: Old-growth west of Cascade crest – Stands of at least 2 tree species, forming a multi- layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha ) > 32 in (81 cm) dbh or > 200 years of age. Mature forests – Stands with average diameters exceeding 21 in (53 cm) dbh; crown cover may be less than 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth; 80-200 years old west of the Cascade crest.
☐ Oregon White Oak: Woodland stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PHS report p. 158 – see web link above).
☒ Riparian: The area adjacent to aquatic systems with flowing water that contains elements of both aquatic and terrestrial ecosystems which mutually influence each other.
☐ Westside Prairies: Herbaceous, non-forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PHS report p. 161 – see web link above).
☒ Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources.
☐ Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition of relatively undisturbed are in WDFW
report – see web link on previous page).
☐ Caves: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human.
☐ Cliffs: Greater than 25 ft (7.6 m) high and occurring below 5000 ft elevation.
☐ Talus: Homogenous areas of rock rubble ranging in average size 0.5 - 6.5 ft (0.15 - 2.0 m), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs.
☒ Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 20 in (51 cm) in western Washington and are > 6.5 ft (2 m) in height. Priority logs are > 12 in (30 cm) in diameter at the largest end, and > 20 ft (6 m) long.
Note: All vegetated wetlands are by definition a priority habitat but are not included in this list because they are addressed elsewhere.
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 16
CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS
Wetland Type
Check off any criteria that apply to the wetland. Circle the category when the appropriate criteria are met.
Category
SC 1.0. Estuarine wetlands
Does the wetland meet the following criteria for Estuarine wetlands?
☐ The dominant water regime is tidal,
☐ Vegetated, and
☐ With a salinity greater than 0.5 ppt ☐Yes –Go to SC 1.1 ☒No= Not an estuarine wetland
SC 1.1. Is the wetland within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area
Preserve, State Park or Educational, Environmental, or Scientific Reserve designated under WAC 332-30-151?
☐Yes = Category I ☐No - Go to SC 1.2
Cat. I
SC 1.2. Is the wetland unit at least 1 ac in size and meets at least two of the following three conditions?
☐ The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has
less than 10% cover of non-native plant species. (If non-native species are Spartina, see page 25)
☐ At least ¾ of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or
un- mowed grassland.
☐ The wetland has at least two of the following features: tidal channels, depressions with open water,
or contiguous freshwater wetlands. ☐Yes = Category I ☐No= Category II
Cat. I
Cat. II
SC 2.0. Wetlands of High Conservation Value (WHCV)
SC 2.1. Has the WA Department of Natural Resources updated their website to include the list of Wetlands of High
Conservation Value? ☐Yes – Go to SC 2.2 ☒No – Go to SC 2.3
SC 2.2. Is the wetland listed on the WDNR database as a Wetland of High Conservation Value?
☐Yes = Category I ☐No = Not a WHCV
SC 2.3. Is the wetland in a Section/Township/Range that contains a Natural Heritage wetland?
http://www1.dnr.wa.gov/nhp/refdesk/datasearch/wnhpwetlands.pdf
☐Yes – Contact WNHP/WDNR and go to SC 2.4 ☒No = Not a WHCV
SC 2.4. Has WDNR identified the wetland within the S/T/R as a Wetland of High Conservation Value and listed it on
their website? ☐Yes = Category I ☐No = Not a WHCV
Cat. I
SC 3.0. Bogs
Does the wetland (or any part of the unit) meet both the criteria for soils and vegetation in bogs? Use the key
below. If you answer YES you will still need to rate the wetland based on its functions.
SC 3.1. Does an area within the wetland unit have organic soil horizons, either peats or mucks, that compose 16 in or
more of the first 32 in of the soil profile? ☐Yes – Go to SC 3.3 ☒No – Go to SC 3.2
SC 3.2. Does an area within the wetland unit have organic soils, either peats or mucks, that are less than 16 in deep
over bedrock, or an impermeable hardpan such as clay or volcanic ash, or that are floating on top of a lake or
pond? ☐Yes – Go to SC 3.3 ☒No = Is not a bog
SC 3.3. Does an area with peats or mucks have more than 70% cover of mosses at ground level, AND at least a 30%
cover of plant species listed in Table 4? ☐Yes = Is a Category I bog ☐No – Go to SC 3.4
NOTE: If you are uncertain about the extent of mosses in the understory, you may substitute that criterion by
measuring the pH of the water that seeps into a hole dug at least 16 in deep. If the pH is less than 5.0 and the
plant species in Table 4 are present, the wetland is a bog.
SC 3.4. Is an area with peats or mucks forested (> 30% cover) with Sitka spruce, subalpine fir, western red cedar,
western hemlock, lodgepole pine, quaking aspen, Engelmann spruce, or western white pine, AND any of the
species (or combination of species) listed in Table 4 provide more than 30% of the cover under the canopy?
☐Yes = Is a Category I bog ☐No = Is not a bog
Cat. I
Wetland name or number: NR01
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 17
SC 4.0. Forested Wetlands
Does the wetland have at least 1 contiguous acre of forest that meets one of these criteria for the WA
Department of Fish and Wildlife’s forests as priority habitats? If you answer YES you will still need to rate
the wetland based on its functions.
☐ Old-growth forests (west of Cascade crest): Stands of at least two tree species, forming a multi-layered
canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha) that are at least 200 years of
age OR have a diameter at breast height (dbh) of 32 in (81 cm) or more.
☐ Mature forests (west of the Cascade Crest): Stands where the largest trees are 80- 200 years old OR
the species that make up the canopy have an average diameter (dbh) exceeding 21 in (53 cm).
☐Yes = Category I ☒No = Not a forested wetland for this section
Cat. I
SC 5.0. Wetlands in Coastal Lagoons
Does the wetland meet all of the following criteria of a wetland in a coastal lagoon?
☐ The wetland lies in a depression adjacent to marine waters that is wholly or partially separated
from marine waters by sandbanks, gravel banks, shingle, or, less frequently, rocks
☐ The lagoon in which the wetland is located contains ponded water that is saline or brackish (> 0.5
ppt) during most of the year in at least a portion of the lagoon (needs to be measured near the
bottom)
☐Yes – Go to SC 5.1 ☒No = Not a wetland in a coastal lagoon
SC 5.1. Does the wetland meet all of the following three conditions?
☐ The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing), and has
less than 20% cover of aggressive, opportunistic plant species (see list of species on p. 100).
☐ At least ¾ of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or
un- mowed grassland.
☐ The wetland is larger than 1/10 ac (4350 ft2)
☐Yes = Category I ☐No = Category II
Cat. I
Cat. II
SC 6.0. Interdunal Wetlands
Is the wetland west of the 1889 line (also called the Western Boundary of Upland Ownership or WBUO)? If
you answer yes you will still need to rate the wetland based on its habitat functions.
In practical terms that means the following geographic areas:
☐ Long Beach Peninsula: Lands west of SR 103
☐ Grayland-Westport: Lands west of SR 105
☐ Ocean Shores-Copalis: Lands west of SR 115 and SR 109
☐Yes – Go to SC 6.1 ☒No = not an interdunal wetland for rating
SC 6.1. Is the wetland 1 ac or larger and scores an 8 or 9 for the habitat functions on the form (rates H,H,H or H,H,M
for the three aspects of function)? ☐Yes = Category I ☐No – Go to SC 6.2
SC 6.2. Is the wetland 1 ac or larger, or is it in a mosaic of wetlands that is 1 ac or larger?
☐Yes = Category II ☐No – Go to SC 6.3
SC 6.3. Is the unit between 0.1 and 1 ac, or is it in a mosaic of wetlands that is between 0.1 and 1 ac?
☐Yes = Category III ☐No = Category IV
Cat I
Cat. II
Cat. III
Cat. IV
Category of wetland based on Special Characteristics
If you answered No for all types, enter “Not Applicable” on Summary Form NA
Wetland Rating System for Western WA: 2014 Update Rating Form – Effective January 1, 2015 18
Wetland name or number
This page left blank intentionally
W ETLAND NR01
2014 W ETLAND R ATING F ORM F IGURES
Figure 1. Map of Cowardin plant classes with 150-foot buffer for Wetland NR01. ........... 2
Figure 2. Map of hydroperiods for Wetland NR01. .......................................................... 3
Figure 3. Approximate 1 km polygon that extends from Wetland NR01 edge including
polygons for undisturbed and moderate intensity land use. ...................... 4
Figure 4. Screen capture of map of 303d listed waters in basin (from Ecology web site). 5
Figure 5. Screen capture of list of TMDL’s for WRIA in which wetland unit is found (from
web). ........................................................................................................ 6
2
Figure 1. Map of Cowardin plant classes with 150-foot buffer for Wetland NR01.
S4.1 – Scrub-shrub and emergent
Cowardin classes are considered
both dense and rigid.
Emergent
Scrub-shrub
3
Figure 2. Map of hydroperiods for Wetland NR01.
Saturated only
Occasionally flooded
4
Figure 3. Approximate 1 km polygon that extends from Wetland NR01 edge including polygons
for undisturbed and moderate intensity land use.
1 km polygon
Moderate intensity
(orange)
Undisturbed
(purple)
High Intensity
5
Figure 4. Screen capture of map of 303d listed waters in basin (from Ecology web site).
Approximate
location of wetland
6
Figure 5. Screen capture of list of TMDL’s for WRIA in which wetland unit is found (from
web).
A P P E N D I X C
2017 Delineation Study Update
November 29, 2017
Kelly Purnell
Project Manager
PSE Energize Eastside
355 110th Avenue NE
Bellevue, WA 98004
Via email: Kelly.Purnell@pse.com
Re: PSE Energize Eastside Project – 2017 Additional Wetland and
Stream Delineation in Renton
The Watershed Company Reference Number: 111103.8
Dear Kelly:
This letter presents the findings of an additional wetland and stream delineation study
in the vicinity of the Energize Eastside Project (the Project) in Renton. Original wetland
and stream delineation field work for the Project in Renton occurred in 2015 and
is documented in the City of Renton Critical Areas Delineation Report: Puget Sound Energy
– Energize Eastside Project (The Watershed Company 2016; hereafter “Renton Delineation
Report”). Project design changes warranted additional wetland and stream
delineation inventory and assessment. This letter documents the findings of the
latest delineation effort in Renton; it is intended to be included as an appendix to
the City of Renton Critical Areas Report: Puget Sound Energy – Energize Eastside Project (The
Watershed Company 2017; hereafter “Renton CAR”). The following documents are
enclosed:
Wetland Determination Data Forms
2014 Ecology Wetland Rating Forms and Figures for wetlands outside of
shoreline jurisdiction
2004 Ecology Wetland Rating Forms for wetlands in shoreline jurisdiction
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 2
Study Area
The study area for the original 2015 delineation field work was an approximate 100-foot
wide corridor based on the location of two existing transmission lines which were
typically spaced approximately 50 feet apart. If the field, study area boundaries were
determined by measuring 25 feet out from the center of each pole set. The approximate
study area is depicted in Appendix A (Critical Area Delineation Maps) of the Renton
Delineation Report. The length of the corridor was approximately 3.7 miles in Renton,
but specifically excluded the lower portion of the Cedar River ravine, described as
follows: on the south side of the ravine, survey limits included the area approximately
425 feet north-northwest beyond the existing structure(s); and on the north side of the
ravine, survey limits included the area approximately 250 feet south-southeast beyond
the existing structure(s).
As the Project design has become more refined, the need for additional delineation was
identified in the vicinity of the Cedar River (previously excluded) and south of the
original study area corridor between the Talbot Hill substation and Shadow Hawk
neighborhood. These areas are depicted approximately in Figure 1 below.
The portion of a wetland boundary adjacent to the original study area corridor was also
captured during this additional field work, located at the base of the slope between the
Cedar River Trail and Shadow Hawk neighborhood (Figure 1).
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 3
Figure 1. Approximate locations of additional wetland and stream delineation study areas
(orange).
Methods
Public-domain information on the study area was reviewed for this delineation study
and include the following:
USDA Natural Resources Conservation Service, Web Soil Survey (WSS)
application
U.S. Fish and Wildlife Service National Wetland Inventory (NWI) maps
Washington Department of Fish and Wildlife interactive mapping programs
(PHS on the Web and SalmonScape)
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 4
Washington Department of Natural Resources, Forest Practices Application
Mapping Tool (FPARS)
Washington Department of Natural Resources, Wetlands of High
Conservation Value Map Viewer
King County’s GIS mapping website (iMap)
City of Renton (COR) maps
Characterization of climatic conditions for precipitation was determined using the
WETS table methodology from the USDA NRCS document Part 650 Engineering Field
Handbook, National Engineering Handbook, Hydrology Tools for Wetland Identification and
Analysis, Chapter 19 (September 2015). The Seattle-Tacoma International AP station as
recorded by NOAA (http://agacis.rcc-acis.org/) was used as a source for precipitation
data. The WETS table methodology uses climate data from the three months prior to the
site visit month to determine if normal conditions are present.
Wetlands
The study area was evaluated for wetlands using methodology from the Regional
Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains,
Valleys, and Coast Region Version 2.0 (Regional Supplement) (US Army Corps of
Engineers [Corps] May 2010). Wetland boundaries were determined on the basis of an
examination of vegetation, soils, and hydrology. Areas meeting the criteria set forth in
the Regional Supplement were determined to be wetland. Soil, vegetation, and
hydrologic parameters were sampled at several locations along the wetland boundary to
make the determination.
Identified wetlands within the study area were classified using the 2014 Update to the
Western Washington Wetland Rating System (Hruby 2014; hereafter “2014 Rating System”),
in accordance with Renton’s critical area regulations. If wetlands in the study area were
located in shoreline jurisdiction, they were rated using the Washington State Wetland
Rating System for Western Washington, Version 2 (Hruby 2004; hereafter “2004 Rating
System”), in accordance with Renton’s Shoreline Management Program (SMP).
Streams
The study area was evaluated for streams based on the presence or absence of an
ordinary high water mark (OHWM) as defined by the Revised Code of Washington
(RCW) 90.58.030 and the Washington Administrative Code (WAC) 220-660-030. The
OHWM edge was located by examining the bed and bank physical characteristics and
vegetation. Streams were classified according to applicable Renton regulations.
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 5
GPS Location
Wetland boundaries, stream OHWM edges or centerlines, data points, and other
features were GPS-located using a hand-held Trimble Geo-XH unit. Following field
location, the GPS data were differentially corrected using GPS Pathfinder Office and
exported into ESRI ArcGIS software for mapping.
Findings
Wetlands
Four wetlands were entirely or partially delineated during this recent field work effort.
Two additional wetlands were identified, but not delineated. These six features are
described below.
Wetland NR02
Wetland NR02 is a depressional wetland located south of the Cedar River crossing.
Vegetation is dominated by palustrine scrub-shrub and palustrine forested vegetation
classes. A large portion of this wetland in permanently ponded. The pond appears to
have been created from beaver activity in 2011-2012 based on Google Earth aerial
images. The ponded area has transitioned from palustrine forested/scrub-shrub
vegetation to palustrine aquatic bed and open water. As a result, standing snags and
downed woody debris are abundant in the permanently ponded area. Common plants
observed include red alder, black cottonwood, salmonberry, redtwig dogwood, skunk
cabbage and lady fern. Sampled wetland soils (DP-5) were a silty loam and met the
criteria for hydric soil indicator Hydrogen Sulfide (A4). Hydrogen Sulfide Odor (C1)
was also the primary hydrology indicator observed. In addition, soils were nearly
saturated and met two secondary hydrology indicators. Wetland NR02 is primarily
supported by groundwater seeps and groundwater supplied by a culvert at the eastern
end of the wetland that conveys water from Wetland NR03, south of the Cedar River
Trail. Hydrology is also affected by the historic beaver activity in the area.
Wetland NR03
Wetland NR03 is a depressional wetland located southeast of Wetland NR02, on the
opposite side of the Cedar River Trail. The majority of the wetland is permanently
ponded. Vegetation is dominated by palustrine scrub-shrub and palustrine aquatic bed
vegetation classes with a considerable amount of dead wood also present. Common
plants observed include willows, salmonberry, redtwig dogwood, Himalayan
blackberry, bittersweet nightshade, soft rush, and duckweed. Sampled wetland soils
(DP-6) were a loam/clay loam and met the criteria for hydric soil indicator Hydrogen
Sulfide (A4) and Redox Dark Surface (F6). Primary hydrology indicators observed at the
test pit include Saturation (A3), Hydrogen Sulfide Odor (C1), and Oxidized
Rhizospheres along Living Roots (C3). Wetland NR03 is primarily supported by a high
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 6
groundwater table. A culvert under the trail conveys water to Wetland NR02 to the
northwest.
Wetland NR04
Wetland NR04 is a slope wetland located west of the Shadow Hawk Condominiums.
Vegetation is dominated by a palustrine emergent vegetation class. Common plants
observed include reed canarygrass, stinging nettle, Himalayan blackberry, lady fern,
and salmonberry. Sampled wetland soils (DP-8) were a clay loam and met the criteria
for hydric soil indicator Redox Dark Surface (F6). Primary hydrology indicators were
not observed at the test pit, but conditions at the data point met the criteria for two
secondary hydrology indicators. Wetland NR04 is primarily supported by groundwater
seeps and supplemented by surface water and precipitation.
Wetland NR05
Wetland NR05 is a depressional wetland located east of SE Cedar Ridge Drive near the
southern end of the study area. Vegetation is classified as palustrine forested, palustrine
scrub-shrub and palustrine emergent. Common plants observed include red alder,
Oregon ash, salmonberry, cattail, lady fern, giant horsetail, soft rush, and small-fruited
bulrush. Sampled wetland soils (DP-10 and DP-12) were a gravelly clay loam and met
the criteria for hydric soil indicator Redox Dark Surface (F6). Soils in the wetland were
saturated and conditions at the data point met the criteria for two secondary hydrology
indicators. Wetland NR05 is primarily supported by groundwater seeps and
supplemented by surface water and precipitation.
Cedar North Wetland (not delineated)
The Cedar North Wetland is a slope wetland located at a break in the steep slope north
of the Maple Valley Highway/State-Route (SR)-169. Soil saturation, surface water seeps,
and obligate plants were observed in this wetland. The approximate size and location of
this wetland has been drawn based on field observations, aerial images, and
topography. The Cedar North Wetland is presumably located in shoreline jurisdiction
based on the approximate wetland boundary.
Talbot Wetland (not delineated)
The Talbot Wetland is a small, depressional wetland located north of the Talbot Hill
substation. Vegetation is dominated by facultative and facultative wetland plants, soils
meet at least one hydric soil indicator, and two secondary hydrology indicators were
observed during the site visit. The approximate size and location of this wetland has
been depicted based on field observations, aerial images, and topography.
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 7
Streams
No new streams were identified in the study area during recent field work activities.
However, the extent or OHWM location of two streams previously discussed in the
delineation report were expanded/collected.
In the Renton Delineation Report, the Cedar River was discussed and depicted, but had
not been delineated. During recent field work activities, the OHWM of the left bank of
the Cedar River was delineated; the right bank of the Cedar River in the study area was
not easily accessible and located at the edge of a large concrete retaining wall supporting
the Maple Valley Highway/SR-169 and was not delineated. For the right bank of the
Cedar River, the OHWM is presumed to be consistent with the mapped Cedar River
floodway. By comparison, on the left bank, the floodway is more encumbering than the
delineated OHWM edge.
The extent of Stream NR02 was expanded downstream near the Cedar River, beginning
at a culvert outlet under the Cedar River Trail, to where it meets Wetland NR02 and
flows west outside of the study area. Stream NR02 originates at the north end of
Wetland NR04 and flows north parallel to the study area, before entering the study area
again (as previously described) near the Cedar River Trail.
R egulatory Implications
Critical areas in the City of Renton are regulated in the Renton Municipal Code (RMC),
Title IV Development Regulations, Chapter 3 Environmental Regulations and Overlay
District, 4-3-050 Critical Areas Regulations. Shorelines, and wetlands located in shoreline
jurisdiction, are regulated under the Renton Shoreline Master Program (RMC 4-3-090).
According to RMC 4-3-050-G.9, wetlands located outside of shoreline jurisdiction are
classified based on the 2014 Rating System. Wetland buffers are measured from the
wetland edge and are based upon the wetland rating, associated habitat score, and
impact of land use. The adjacent land use would not be considered low intensity,
therefore the buffer width for “all other land uses” applies. Table 1 shows the ratings for
wetlands that are not located in shoreline jurisdiction and the associated standard buffer
widths.
Wetland NR02 and (presumably) Cedar North Wetland are located within shoreline
jurisdiction and therefore the regulations in RMC 4-3-090 apply. Wetlands in shoreline
jurisdiction are rated using the 2004 version of the Ecology rating system. Wetland
buffer widths are determined based upon the wetland rating and associated habitat
score. Wetland NR02 is a Category II wetland with a high habitat score and requires a
standard buffer width of 225 feet (Table 2).
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 8
Classifications and buffer widths for wetlands that were not formally delineated or rated
(Cedar North and Talbot Wetlands) have been estimated in Tables 1 and 2, below.
Estimated buffer widths were used to determine if Project activities are likely or unlikely
to affect these critical areas.
Table 1. Wetland ratings and associated buffer widths for wetlands located outside of shoreline
jurisdiction.
Wetland
Name
2014 Rating System Category
Standard
Buffer Width
(feet) Water Quality Hydrology Habitat Total
NR03 6 5 7 18 III 100
NR04 5 5 6 16 III 100
NR05 5 6 7 18 III 100
Talbot* -- -- -- -- ~III ~100
* Wetland not delineated or formally rated; rating is estimated and a moderate habitat score
is presumed to determine approximate buffer width.
Table 2. Wetland rating and associated buffer width for Wetland NR02 located in shoreline
jurisdiction.
Wetland
Name
2004 Rating System Category
Standard
Buffer Width
(feet) Water Quality Hydrology Habitat Total
NR02 12 12 29 53 II 225
Cedar
North* -- -- -- -- ~III ~125
* Wetland not delineated or formally rated; rating is estimated and a moderate habitat score
is presumed to determine approximate buffer width.
The additional delineation of streams in the study area do not change the regulatory
implications described in the Renton Delineation Report. Therefore, they are not
discussed further here.
Disclaimer
The information contained in this letter is based on the application of technical
guidelines currently accepted as the best available science and in conjunction with the
manuals and criteria outlined in the methods section. All discussions, conclusions and
recommendations reflect the best professional judgment of the author(s) and are based
upon information available at the time the study was conducted. All work was
completed within the constraints of budget, scope, and timing. The findings of this
2017 Renton Wetland and Stream Delineation Study
PSE, Kelly Purnell
December 2017
Page 9
report are subject to verification and agreement by the appropriate local, state and
federal regulatory authorities. No other warranty, expressed or implied, is made.
Please call if you have any questions or if we can provide you with any additional
information.
Sincerely,
Katy Crandall, WPIT
Ecologist / Arborist
Enclosures
A P P E N D I X D
Detailed CAIA Methodology
A PPENDIX D
Detailed CAIA Methodology
This detailed Critical Area Impact Analysis (CAIA) is intended to further
describe the methods used to generate critical area features and existing land
cover classes used in conjunction with PSE site plans in order to quantify impacts
resulting from implementation of the Energize Eastside Project (“the Project”).
This Appendix is meant to complement and expand upon the methods described
in the body of the Critical Area Report.
Methodology Outline:
Critical Area Delineation and Mapping Methods
- Wetlands
- Streams
- Functioning Wetland and Stream Buffers
- Geologic Hazard Areas
- Shoreline Jurisdiction
Existing Land Cover Mapping
- Vegetation Assessment Methods
Impact Characterization
- Energize Eastside 230K Line
- Lake Tradition 115K Line
Critical Areas Impact Assessment
Quality Assurance Review of Analysis Steps and Results
Limitations
Data Sources Table
The Watershed Company
January 2018
II
Critical Area Delineation and Mapping Methods
Wetland and stream critical areas were delineated and classified by The
Watershed Company between March and October 2015 coincident with the field
work for vegetation inventory analysis. These delineated features were GPS‐
located. Responding to the design alignment provided by PSE in November and
December 2017, supplemental reconnaissance and vegetation inventory was
conducted to ensure coverage of the full project corridor.
Critical area features not delineated in the field were mapped using publicly‐
available contour and aerial GIS data, which was then refined according to
observations of the ecologists who conducted the field reconnaissance. A table
provided at the end of this document lists data sources for each mapped critical
area.
Wetland Delineation
The study area was evaluated for wetlands using methodology from the Regional
Supplement to the Corps of Engineers Wetland Delineation Manual: Western
Mountains, Valleys, and Coast Region Version 2.0 (Regional Supplement) (US Army
Corps of Engineers [Corps] May 2010). Wetland boundaries were determined on
the basis of an examination of vegetation, soils, and hydrology. Areas meeting
the criteria set forth in the Regional Supplement were determined to be wetland.
Soil, vegetation, and hydrologic parameters were sampled at several locations
along the wetland boundary to make the determination.
Identified wetlands outside of shoreline jurisdiction have been classified using
the 2014 Update to the Western Washington Wetland Rating System (Ecology
publication #14‐06‐029) per Renton regulations. Wetlands within shoreline
jurisdiction have been classified using the 2004 Ecology rating system per Renton
Municipal Code (RMC) 4‐3‐090.D.2.d.ii.
Stream Delineation
The study area was also evaluated for streams based on the presence or absence
of an ordinary high water mark (OHWM) as defined by the Revised Code of
Washington (RCW) 90.58.030 and the Washington Administrative Code (WAC)
220‐660‐030. The OHWM edge was located by examining the bed and bank
physical characteristics and vegetation.
The centerlines of streams in the study area were recorded in the field, with
stream widths approximated in the field and based on aerial photometry and
elevation contours. Streams were classified according to the RMC.
The Watershed Company
January 2018
III
Functioning Wetland and Stream Buffers Mapping
Standard buffers were applied to delineated wetland and stream edges in GIS
according to regulatory buffer widths in RMC Section 4‐3‐050 (Critical Areas
Regulations). In some cases, developed areas intruded into these mapped
standard buffers. To remove these non‐functioning buffer areas from the
assessment of Project impacts, developed areas (see land cover mapping section)
were manually removed from the standard buffer polygons in GIS (based on
observed field conditions and recent aerial photography). The resulting
functioning buffers were used to determine buffer impacts and mitigation needs.
Geologic Hazard Areas and Buffers Mapping
Five regulated geologic hazard area types occur within the Project corridor in
Renton including erosion hazards areas, landslide hazards areas, seismic hazard
areas, coal mine hazard areas, and steep slopes. According to RMC 4‐3‐050(G)(2),
and the GeoEngineers Report (Appendix C), landslide hazard areas categorized
as “very high” require a 50‐foot buffer and 15‐foot setback from the top, toe, and
sides of the slope, while no buffer is applied to any other type of geologic hazard
area. No very high landslide hazard areas are mapped within the Project area.
Geospatial inventories of erosion, coal mine, seismic, and landslide hazards areas
that are published by City of Renton GIS were used for this effort. The datasets
were then clipped to the 500‐foot study corridor.
Steep slopes in Renton are categorized and regulated as either “sensitive” or
“protected” depending on grade and vertical rise. However, steep slope data
provided by the City do not provide category information for the mapped
features. In order to supplement the City’s inventory with this information, The
Watershed Company generated steep slope hazard area data using high‐
resolution LIDAR data provided by PSE that represents the bare earth
topographic surface for the greater study area. Topographic surface data were
analyzed to identify and isolate areas where the slope of the ground surface is 40
percent or steeper. Features were then reanalyzed to identify and isolate slopes
with an elevation change of at least 15 feet of vertical relief. These features were
assigned the category of “protected,” while the remaining features were assigned
the category of “sensitive.” The dataset was then clipped to the 500‐foot study
corridor.
Shoreline Jurisdiction
Within the Project area, the Cedar River is designated as a Shoreline of the State
and therefore subject to the City’s Shoreline Master Program (RMC 4‐3‐090).
Shoreline jurisdiction is defined in RMC 4‐3‐090(B)(3) to include: a) lands within
200 feet from the OHWM, or lands within 200 feet from floodways, whichever is
greater; b) contiguous floodplain areas; and c) all marshes, bogs, swamps, and
The Watershed Company
January 2018
IV
river deltas associated with streams, lakes, and tidal waters that are subject to the
provisions of the State Shoreline Management Act (SMA).
A combination of field data and GIS inventories were used to map Cedar River
shoreline jurisdiction. Floodway and floodplain areas were provided by City of
Renton GIS. Within the Project area, no floodplain extends outside of the
mapped floodway. The mapped floodway overlaps with the delineated OHWM
on the north bank of the river and extends slightly beyond it on the south bank.
As a result, a buffer of 200 feet was applied to the Cedar River floodway to form
the basis for shoreline jurisdiction. On the south bank of the river, a delineated
wetland falls within that 200‐foot buffer and extends outside of the 200‐foot
buffer to the south. Consistent with the SMA and RMC, this wetland was
considered “associated” with the Cedar River, and shoreline jurisdiction was
extended to encompass its entire delineated boundary. A potential wetland was
also identified within 200 feet of the OHWM on the northern bank of the Cedar
River, which likely extends outside of the 200‐foot buffer to the north. However,
this feature was not delineated. Therefore, the extent of shoreline jurisdiction on
the north side of the Cedar River is approximated, conservatively, to encompass
the approximated area of this wetland.
Other critical areas mapped and analyzed include: Priority Habitat Protection
Areas, Floodway, Floodplain, and Wellhead Protection Areas. These layers were
downloaded from various sources and can be found in the Data Sources table at
the end of this document.
Existing Land Cover Mapping
In order to quantify land cover changes from Project‐related activities, a layer
showing existing land use was created to describe the current land cover
conditions. The land cover base map was developed from the following existing
data sources:
• 2009 Impervious and Impacted Surface raster data set, King County GIS
• Energize Eastside Corridor digital survey, APS Surveying, received May
2016
• Energize Eastside Corridor Tree Inventory data, The Watershed
Company, compiled 2015‐2017
• Energize Eastside Corridor Vegetation Polygon data, The Watershed
Company, compiled 2015‐2017
• Energize Eastside Corridor Wetland and Stream Inventory, The
Watershed Company, compiled 2015‐2017
• High‐resolution aerial photography, PSE, captured in 2011
• 2015‐2016 aerial photography, King County GIS
The Watershed Company
January 2018
V
Using the King County impervious surface raster, GIS analysts supplemented the
mapped features using digital survey data. These data were further refined by
manually reviewing mapped features against high‐resolution aerial photography
and field‐verified conditions. After developed and non‐developed areas were
mapped, vegetation and tree canopy coverage information were integrated
(described in following subsection), as well as mapped open water areas
(streams). This effort yielded a base map with six general land cover types:
• Forested with understory vegetation
• Forested without understory vegetation
• Understory vegetation, unforested
• Other (generally lawn)
• Developed
• Water
Vegetation Assessment Methods
A full description of the vegetation analysis methods, the results of which have
been incorporated into the CAIA, is presented in the City of Renton Tree Inventory
Report: Puget Sound Energy – Energize Eastside Project (The Watershed Company
2016b). The ways in which the results were used to generate the mapped features
presented in the CAIA are summarized below.
The Watershed Company certified arborists conducted a field‐based vegetation
inventory from March 23, 2015, to November 9, 2015 associated with potential
routes for the Energize Eastside Project. The methodology utilized during the
inventory was developed to comprehensively identify, describe, and mark all
vegetation greater than 15 feet tall, or that had the potential to reach a mature
height of 15 feet or taller. Supplemental inventory was conducted using the same
methodology in November and December 2017.
Inventoried vegetation was mapped as points and/or polygons. Any tree with a
diameter of six inches at four‐and‐a‐half feet above the ground surface (DBH)
was mapped as a point and tagged with a unique number and its attributes were
recorded. Landscaped vegetation with the potential to reach 15 feet or greater
was also inventoried in this manner regardless of size. Finally, weedy vegetation
(i.e., from seed [not planted] and not maintained) with a DBH of three to six
inches was also inventoried in this way. This type of inventoried vegetation was
typically survey‐located.
In some instances, The Watershed Company certified arborists could not access
or did not inventory vegetation that was previously or subsequently picked up
by survey crews. This limitation was caused by a number of reasons that include
a change in property access permissions; survey crew assessment limits as
compared to the tree inventory study area; and/or the species, size, or condition
The Watershed Company
January 2018
VI
of the tree or large shrub in question. Vegetation that was survey‐located but not
inventoried by arborists has been incorporated into the CAIA analysis with an
assumed maximum potential height of 25 feet and radius of 9 feet, as a rule. This
assumption was based on the typical characteristic observed over majority of the
project corridor. However, other attribute data associated with the survey‐
located only vegetation, such as species and condition, was not collected and no
assumption was applied.
A similar rule was applied in the area south of the Cedar River where trees were
surveyed, but not inventoried by The Watershed Company crews. Based on the
tree characteristics and species composition observed in this area, it was
determined that the previously stated assumption of 25 feet for maximum
potential height would be a significant underestimation. Lacking an arborist’s
identification of tree species that could be used to assign maximum potential
height, a proxy was used in the form of the surveyors’ notes. In order to
approach a more accurate assumption for maximum potential height that could
help determine potential tree impacts in this area, maximum vegetation height
was based on the “best guess” tree species notes from the surveyors. The canopy
radius was presumed to be 9 feet.
Under the standard vegetation control parameters, some trees within the
shoreline jurisdiction of the Cedar River would be removed. However, as
communicated by PSE, no trees within shoreline jurisdiction will be removed by
this Project. Where eventual conflicts between wire elevation and maximum
potential tree height are predicted, conflicts will be abated by other means, such
as pruning. Therefore, no tree removal impacts are shown to occur within
shoreline jurisdiction.
Hedges and small weedy vegetation (less than three inches DBH) were mapped
as polygons, not points. Polygons were sketched in the field based on
observations then digitized in GIS using high‐resolution imagery. Vegetation
attributes within polygons were averaged. No significant (regulated) trees were
inventoried using this method.
Resulting mapped features included in land cover mapping of the CAIA are
vegetation points with the recorded canopy (or radius) applied creating circular
“tree footprints” and polygons representing varying densities of smaller weedy
vegetation with the potential to reach a height of 15 feet or more.
Using inventoried tree point data and incorporation of 3D design data depicting
proposed pole heights and vertical wire alignment, tree impacts related to the
construction of the Project were quantified. Canopy cover for the anticipated
trees to remain and trees to be removed or maintained was then mapped and
overlaid, resulting in a polygon layer depicting the extent of anticipated canopy
The Watershed Company
January 2018
VII
preservation and canopy loss. This data was incorporated into the land cover
data, further refining existing land cover into eight general land cover types:
• Forested to be removed (canopy loss) with understory
• Forested to be removed, no understory
• Forested to remain (canopy preservation) with understory
• Forested to remain, no understory
• Understory vegetation, unforested
• Other (generally lawn)
• Developed
• Water
Impact Characterization
As the work associated with this permit application includes improvements on
two powerline corridors—the Energize Eastside and Lake Tradition lines—two
approaches were used to calculate critical area impacts within the City of Renton.
Energize Eastside 230K Line
Proposed development areas associated with the Energize Eastside Project were
mapped using geometry from design files and data provided by PSE. As
described by PSE, work proposed in Renton could be classified into eight types
and maintained in the long term as described in the following table.
The Watershed Company
January 2018
VIII
These proposed work areas were then intersected with the land cover data set
described above. The result was a set of polygons defining pre‐Project conditions
(land cover data set values) and post‐Project conditions (proposed work and
long‐term condition values). Differences between post‐Project conditions and
pre‐Project conditions, or impacts, were then characterized as one of four types –
permanent, conversion, temporary, or no change – based on the nature of the
change on the ground. These characterization types are defined in the matrix
below.
Proposed Work Long term Condition
Pole footprint Developed
Pole buffer, describes an approximate 6‐foot
buffer around the proposed poles that will be
disturbed during construction and tree
growth will be managed long‐term
Mixed Vegetation (Height maintained at 15 feet or
where 20 feet of vertical clearance is provided
beneath the vertical curvature of the lowest wire)
Access route, describes approximate path
used during construction activities
Mixed Vegetation (Height may be maintained
depending upon location relative to wire alignment)
Stringing sites* Mixed Vegetation (Height may be maintained
depending upon location relative to wire alignment)
Wire zone (WZ)
Mixed Vegetation (Height maintained at 15 feet or
where 20 feet of vertical clearance is provided
beneath the vertical curvature of the lowest wire)
Managed right‐of‐way (MROW)
Mixed Vegetation (Height maintained at 15 feet or
where 20 feet of vertical clearance is provided
beneath the vertical curvature of the lowest wire)
Pole work area, approximate temporary
disturbance related to pole construction
Mixed Vegetation (Height may be maintained
depending upon location relative to wire alignment)
Maintained legal right‐of‐way (LROW),
encompasses the areas of LROW where PSE
intends to exercise long‐term vegetation
management
Mixed Vegetation (Height maintained at 70 feet)
* Note: Impacts from stringing sites are captured within the footprints of other proposed work
activities. During construction work associated with stringing sites, adjustments may be made in
the field to avoid, minimize, or mitigate impacts on critical areas should they occur.
The Watershed Company
January 2018
IX
Existing Land Cover Types
Impact
Description
Long-term
Condition1 Forested to be removed with understory Forested to be removed, no understory Forested to remain with understory Forested to remain, no understory Understory Other (mostly lawn) Developed Water Proposed Activities Pole footprint Developed P P P P P P NC N/A
Pole buffer Mixed
vegetation2 C C T T T T NC N/A
Access route
Mixed
vegetation2
C C T T T T NC N/A
Pole work area Mixed
vegetation2 C C T T T T NC N/A
Wire zone Mixed
vegetation2 C C NC NC NC NC NC N/A
Managed
ROW
Mixed
vegetation2 C C NC NC NC NC NC N/A
Maintained
Legal ROW
Mixed
vegetation2 C C NC NC NC NC NC N/A
Type of Impact based on proposed activity, long term condition, and existing land cover type:
P = Permanent to developed C = Vegetation conversion (not developed)
T = Temporary impact, can be restored to existing land cover
NC = No Change N/A = Not applicable/does not occur
1 Long term condition determined in coordination with PSE.
2 Subject to varying height restrictions described in Section 3.3.4.
The Watershed Company
January 2018
X
Lake Tradition 115K Line
Work associated with the Lake Tradition line is restricted to one area of the
project corridor, affecting approximate five adjacent spans. Work includes
resetting existing poles, adding new poles, and rehanging lines on existing poles.
Due to the limited work and the utilization of existing poles, no vegetation
impacts due to conflicts between wire height and tree height are anticipated.
Therefore, for new or replaced poles along the Lake Tradition line, tree removal
impacts were calculated based solely on proximity to proposed pole work areas.
The long‐term condition and impact characterization for “pole work area” was
consistent with the parameters of the Energize Eastside analysis, as described by
the tables in the preceding section.
Critical Areas Impact Assessment
Application of the matrix yielded a map showing a full characterization of
permanent, conversion, and temporary impacts associated with the Project. This
impact characterization layer was then intersected with each individual mapped
critical area in order to locate, characterize, and quantify impacts to that critical
area. The results were summarized by critical area, and for wetlands and
streams, by drainage sub‐basin.
The ending table summarizes the data sources used for the critical areas analysis.
Quality Assurance Review of Analysis Steps and Results
Internal review of CAIA steps and results has occurred throughout the process
described above and will be ongoing as the analysis is refined.
Ecologists, arborists, GIS analysts, and planners worked collaboratively to ensure
all appropriate critical areas were incorporated into the maps and where
appropriate, classified and buffered according the local jurisdiction regulations.
GIS analysts created the land cover base map, compiled from a variety of
sources. Land cover classifications were reviewed for quality assurance first
through the GIS department by comparing mapped data to high resolution aerial
imagery. Following review by the GIS analysts, the land cover map was
reviewed by an ecologist against delineation field notes and recollections from
field work activities.
Project elements and site plans have been provided by, and reviewed with, PSE
Project staff. The mapped location and long‐term condition of Project elements is
based upon discussions with PSE regarding best management practices and
standard PSE programs and policies.
All components of the CAIA have been generated/authored by reputable sources
and have been cross‐checked internally for consistency. Quantified and depicted
The Watershed Company
January 2018
XI
impacts resulting from the CAIA have been reviewed by ecologists for quality
assurance to the extent feasible. Impact results will continue to be reviewed for
accuracy as the Project plans and impact areas are refined and finalized.
Limitations
This analysis relies on a series of data products produced using different scales
and methods; therefore, mapped features may not align with the planned real‐
world layout of proposed corridor facilities. Ground‐truthing of these results
may reveal inaccuracies. Furthermore, as some features and design geometries
were translated from AutoCAD into ArcGIS, some geometric refinements were
necessary to address gaps and other issues, which could affect the accuracy of
the analysis results.
The Watershed Company January 2018 XII Data Inventory Elements and Information Sources: Inventory Element Information Gathered Data Source(s) Assumptions/Limitations Proposed Development Topographic surface data Point map of surface elevations Puget Sound Energy (PSE) tabular data (via email R. Weider); date received 4/19/2017 The Watershed Company (TWC) Point elevations generated from LIDAR flight by consultant to PSE; flight date unknown Data was post‐processed to generate a 3D surface map using ArcGIS software Proposed Energize Eastside Project Improvements Pole structures Wire alignments, including alternate alignment Pole construction work areas Proposed temporary construction access routes Stringing sites PSE (via email R. Weider, K. Purnell), design drawings in AutoCAD; date received: 6/30/2017‐11/6/2017 TWC Reflects pole and wire design configuration from June 30, 2017, with updates through November 6, 2017 Design may be subject to revision or update based on regulatory comments, field conditions, or other factors Cadastral Datasets & Features Land Cover Development and impervious areas Other Tree canopy Understory vegetation King County 2009 impervious dataset and 2015‐2016 aerial data PSE high‐resolution aerial photography; date received 7/7/2015 APS Surveying, digital survey; date received 5/18/2016 TWC Impervious dataset from King County, last updated 2009 Vegetation survey by TWC between 2015 and 2017 “Developed” category includes roads, structures, and heavily disturbed areas, such as compacted unimproved roadways “Other” category observed to be mostly lawn based on visual observation of aerial photographs, but could include other conditions Survey data was post‐processed to isolate and generate geospatial feature classes using ArcGIS software Parks Park locations City of Renton (downloaded 4/6/17) Park boundaries current as of 1/14/2017
The Watershed Company January 2018 XIII Inventory Element Information Gathered Data Source(s) Assumptions/Limitations City limits Shapefile polygons City of Renton (downloaded 6/2/17) Does not reflect annexations beyond download date. Parcels Shapefile polygons City of Renton (downloaded 6/2/17) Does not reflect parcel subdivisions beyond download date. Regulated Critical Areas Streams and Riparian Areas (RMC 4‐3‐050(G)(7)) Streams with study corridor Stream buffers TWC City of Renton (downloaded 4/6/17) Streams delineated by TWC between 2015 and 2017 Feature buffers assigned according to City of Renton 2015 Critical Areas Ordinance (CAO) Floodplains See Flood Hazard Areas Wetlands (RMC 4‐3‐050(G)(9)) Delineated wetlands within study corridor Wetland buffers TWC City of Renton (downloaded 4/6/17) Wetlands delineated by TWC between 2015 and 2017 Wetland feature ratings based on 2014 rating system Feature buffers assigned according to City of Renton 2015 Critical Areas Ordinance (CAO) Fish and Wildlife Habitat Conservation Areas (RMC 4‐3‐050(G)(6)) Priority habitat and species data (PHS) Endangered/listed species WDFW (received 6/27/2017) USFWS No FWHCA features occur within project area Scale may not be sufficient to capture individual occurrences or observations along the corridor Accuracy does not supersede observation by PSE staff Geologic Hazard Areas: Landslide hazard areas (RMC 4‐3‐050 (G)(5)(b)) Erosion hazard areas RMC 4‐3‐050 (G)(5)(c)) Steep slopes (RMC 4‐3‐050 (G)(5)(a)) Landslide hazard areas City of Renton (downloaded 4/6/17) TWC Data describes landslide hazards defined by City of Renton CAO Data is not suitable for smaller scale site‐specific analysis; “Observation of actual on‐site conditions is required to determine if a particular parcel is in a landslide hazard area or not” No very high landslide areas or buffers exist in the project area
The Watershed Company January 2018 XIV Inventory Element Information Gathered Data Source(s) Assumptions/Limitations Coal mine hazard areas (RMC 4‐3‐050 (G)(5)(e)) Seismic hazard areas (RMC 4‐3‐050 (G)(5)(d)) Erosion hazard areas City of Renton (downloaded 4/6/17) Data describes erosion hazards defined by Renton CAO Data is not suitable for smaller scale site‐specific analysis Steep slope hazard areas City of Renton (downloaded 4/6/17) TWC GeoEngineers TWC categorized City of Renton steep slope data through analysis of PSE LIDAR surface data. Areas where slope >= 40% and >15ft of relief were categorized as “protected” No steep slope buffers are required according to City of Renton CAO under table RMC 4‐3‐050 (G)(2) Coal mine hazard areas City of Renton (downloaded 4/6/17) Identification of historical coal mine areas as defined by Renton CAO Seismic hazard areas City of Renton (downloaded 4/6/17) Identification of areas subject to potential surficial liquefaction based on DNR liquefaction data Flood hazard areas (RMC 4‐3‐050 (G)(4)) Flood hazard areas City of Renton (downloaded 4/6/17) Data displays the Cedar River Floodway and 100‐Year Floodplain as defined by Renton CAO Shoreline Jurisdiction (RMC 4‐3‐090(B)(3)) Shoreline jurisdiction TWC Shoreline jurisdiction includes 200‐foot area around mapped floodway, as provided by City of Renton, as well as associated wetlands, as delineated by TWC Wellhead protection areas (RMC 4‐3‐050 (G)(8)) Wellhead protection areas City of Renton (downloaded 4/6/2017) Data displays aquifer protection zone areas
A P P E N D I X E
Geological Hazards Report
Revised Targeted Critical Areas
Geologic Hazards
Energize Eastside Project
Renton, Washington
for
Puget Sound Energy
January 11, 2018
Revised Targeted Critical Areas
Geologic Hazards
Energize Eastside Project
Renton, Washington
for
Puget Sound Energy
January 11, 2018
8410 154th Avenue NE
Redmond, Washington 98052
425.861.6000
January 11, 2018 | Page i
File No. 0186-871-06
Table of Contents
INTRODUCTION ......................................................................................................................................................... 1
LOCAL REGULATIONS .............................................................................................................................................. 1
Code Definitions for Hazard, Hazards Areas, Wellhead Protection Zones and Buffers .................................. 1
EXISTING CONDITIONS ............................................................................................................................................ 4
Field Observations ............................................................................................................................................... 5
Honey Dew Creek .......................................................................................................................................... 5
Cedar River North Slope ............................................................................................................................... 5
Cedar River South Slope ............................................................................................................................... 6
IMPACT ASSESSMENT ............................................................................................................................................. 6
Access Construction ............................................................................................................................................ 7
Pole Installation ................................................................................................................................................... 7
Conclusions .......................................................................................................................................................... 7
Conceptual Impact Mitigation Strategy .............................................................................................................. 8
Vegetation Management and Tree Removal ............................................................................................... 8
CODE COMPLIANCE .............................................................................................................................................. 10
4-3-050 (G2) – Development Standards – Critical Area Buffers ................................................................... 10
4-3-050 (G5f) – Development Standards for Geologically Hazardous Areas – Protected Slopes............... 10
4-3-050 (G5g) – Development Standards for Geologically Hazardous Areas – Sensitive Slopes; Medium,
High and Very High Landslide Hazards; High Erosion Hazards ...................................................................... 10
4-3-050 (G5i(ii)) – Development Standards for Geologically Hazardous Areas – Coal Mine Hazards Found
during Construction .......................................................................................................................................... 10
4-3-050 (G5d) – Development Standards for Geologically Hazardous Areas – Seismic Hazards Found
during Construction .......................................................................................................................................... 11
4-3-050 (G8) – Development Standards for Geologically Hazardous Areas – Wellhead Protection Zones
Found during Construction ............................................................................................................................... 11
LIMITATIONS .......................................................................................................................................................... 12
REFERENCES ........................................................................................................................................................ 12
January 11, 2018 | Page 1
File No. 0186-871-06
INTRODUCTION
GeoEngineers, Inc. (GeoEngineers) is pleased to present this revised report with the results for targeted
critical areas evaluation of specific geologic hazards identified by Puget Sound Energy (PSE) for the
Energize Eastside Project. Our services have been provided in general accordance with the proposal
between GeoEngineers and PSE dated June 21, 2017. These services were authorized by Kelly Purnell
with PSE on June 15, 2017, and formal authorization was received on June 26, 2017. This revised report
supersedes our previous report and addresses comments provided by PSE on January 4, 2018.
The project area is located along existing PSE rights-of-way and includes areas within the City of Renton.
We previously provided a geologic hazard evaluation for various routes under consideration, including the
route evaluated within this document, in a separate report submitted to PSE on December 19, 2014
(GeoEngineers 2014). The geologic hazards evaluation included in this report focuses on a desktop
review for erosion, steep slope, landslide and coal mine hazard areas, and seismic hazards as assigned
by PSE, relative to proposed vegetation management activities, including tree-removal required for
construction access and pole replacement. PSE also requested an evaluation of wellhead protection
areas mapped within the project area. PSE has provided specific locations for evaluation and a map
developed by others that shows proposed pole replacement activities, including proposed tree removal,
vegetation management zones and access roads.
LOCAL REGULATIONS
GeoEngineers assessed local regulations in the City of Renton Critical Areas Regulations, 4-3-050, for the
project areas identified by PSE that coincide with regulated geologic hazard areas.
Code Definitions for Hazard, Hazards Areas, Wellhead Protection Zones and Buffers
GeoEngineers assessed local regulations in the Renton Municipal Code, Definitions, Chapter 4-11 and
Critical Areas, Chapter 4-3-050 for selected geologic hazard areas and wellhead protection zones.
■ Erosion: The wearing away of the ground surface as a result of the movement of wind, water and/or
ice (Renton Municipal Code, 4-11-050).
■ Erosion Hazard Areas:
Low Erosion Hazard (EL): Areas with soils characterized by the Natural Resource
Conservation Service (NRCS) as having slight or moderate erosion potential, and a slope less
than fifteen percent (Renton Municipal Code, 4-3-050).
High Erosion Hazard (EH): Areas with soils characterized by the NRCS as having severe or
very severe erosion potential, and a slope more than fifteen percent (Renton Municipal Code,
4-3-050).
There are no buffer requirements for low or high erosion hazards.
■ Seismic Hazard: Seismic are not described within the Definitions section of the Renton Municipal
Codes as of December 19, 2017 (Renton Municipal Code 4-11-030). However, the Critical Areas
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File No. 0186-871-06
Regulations pertaining to Seismic Hazards does provide a description in Renton Municipal Code and
are as follows:
Low Seismic Hazard (SL): Areas underlain by dense soils or bedrock. These soils generally
have site classifications of A through D, as defined in the International Building Code, 2012.
(Renton Municipal Code 4-3-050).
High Seismic Hazard (SH): Areas underlain by soft or loose, saturated soils. These soils
generally have site classifications E or F, as defined in the International Building Code, 2012.
(Renton Municipal Code 4-3-050).
There are no buffer requirements for high seismic hazards.
■ Slopes, Steep (Also referred to as Steep Slopes): A hillside, or portion thereof, which falls into one of
two (2) classes of slope, sensitive or protected (Chapter 11, Definitions 4-11-190).
Slope, Protected: A hillside, or portion thereof, with an average slope, as identified in the City
of Renton Steep Slope Atlas or in a method approved by the City, of forty percent (40%) or
greater grade and having a minimum vertical rise of fifteen feet (15').
Slope, Sensitive: A hillside, or portion thereof, characterized by: (1) an average slope, as
identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of
twenty five percent (25%) to less than forty percent (40%); or (2) an average slope, as
identified in the City of Renton Steep Slope Atlas or in a method approved by the City, of forty
percent (40%) or greater with a vertical rise of less than fifteen feet (15'), abutting an
average slope, as identified in the City of Renton Steep Slope Atlas or in a method approved
by the City, of twenty five percent (25%) to forty percent (40%). This definition excludes
engineered retaining walls.
There is no established critical area buffer for steep slopes within Renton.
■ Landslide Hazards: Landslide Hazards are not described within the Definitions Section (4-11-030) in
the Renton Municipal Code as of December 19, 2017. However, the Critical Areas Regulations
pertaining to Landslide Hazards are defined in Renton Municipal Code as follows:
Low Landslide Hazard (LL): Areas with slopes less than fifteen percent (Renton Municipal
Code 4-3-050).
Medium Landslide Hazard (LM): Areas with slopes between fifteen percent and forty percent
and underlain by soils that consist largely of sand, gravel or glacial till (Renton Municipal
Code 4-3-050).
High Landslide Hazards (LH): Areas with slopes greater than forty percent, and areas with
slopes between fifteen percent and underlain by soils consisting largely of silt and clay
(Renton Municipal Code 4-3-050).
Very High Landslide Hazards (LV): Areas of known mapped or identified landslide deposits
(Renton Municipal Code 4-3-050).
According to City of Renton’s Critical Area Regulations, a critical area buffer is not required for low to
high landslide hazards. The established critical area minimum buffer for very high landslide hazards
is 50 feet from the top, toe and sides of the slope.
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File No. 0186-871-06
■ Coal Mine Hazard: Coal Mine Hazard are not described within the Definitions section of the Renton
Municipal Codes as of September 18, 2017 (Renton Municipal Code 4-11-030). However, the Critical
Areas Regulations pertaining to Coal Mine Hazards does provide a description in Renton Municipal
Code and are as follows;
Low Coal Mine Hazard (CL): Areas with no known mine workings and no predicted
subsidence. While no mines are known in these areas, undocumented mining is known to
have occurred (Renton Municipal Code 4-3-050).
Medium Coal Mine Hazard (CM): Areas where mine workings are deeper than two hundred
feet (200') for steeply dipping seams, or deeper than fifteen (15) times the thickness of the
seam or workings for gently dipping seams. These areas may be affected by subsidence
(Renton Municipal Code 4-3-050).
High Coal Mine Hazard (CH): Areas with abandoned and improperly sealed mine openings
and areas underlain by mine workings shallower than two hundred feet (200') in depth for
steeply dipping seams, or shallower than fifteen (15) times the thickness of the seam or
workings for gently dipping seams. These areas may be affected by collapse or other
subsidence (Renton Municipal Code 4-3-050).
The are no established critical area buffers for coal mine hazard areas.
Wellhead Protection Area: The definition of Wellhead Protection Area is not provided in the
Definitions Section of the Renton Municipal Codes as of December 20, 2017 (4-11-230).
However, the Critical Areas Regulations pertaining to Wellhead Protection Areas do provide
the following description as follows;
a. Applicability: Developments, facilities, uses and activities discussed in this subsection shall
comply with the applicable provisions and restrictions of this Section and chapters 4-4, 4-5,
4-6, 4-9, and 5-5 RMC for the Wellhead Protection Areas, as classified below, in which the
developments, facilities, uses and activities are located, except as preempted by Federal or
State law. (Renton Municipal Code 4-3-050).
i. Wellhead Protection Areas: Wellhead Protection Areas are the portion of an aquifer
within the zone of capture and recharge area for a well or well field owned or operated
by the City.
ii. Wellhead Protection Area Zones: Zones of a Wellhead Protection Area are designated
to provide graduated levels of Wellhead Protection Area recharge. Zone boundaries
are determined using best available science documented in the City of Renton
Wellhead Protection Plan, an appendix of the City of Renton Water System Plan, as
periodically updated. The following zones may be designated:
(a) Zone 1: The land area situated between a well or well field owned by the City
and the three hundred sixty five (365) day groundwater travel time contour
(Renton Municipal Code 4-3-050).
(b) Zone 1 Modified: The same land area described for Zone 1 but for the purpose
of protecting a high-priority well, wellfield, or spring withdrawing from a confined
January 11, 2018 | Page 4
File No. 0186-871-06
aquifer with partial leakage in the overlying or underlying confining layers. Uses,
activities, and facilities located in this area are regulated as if located within
Zone 1 except as provided by this subsection G8 (Renton Municipal Code 4-3-
050).
(c) Zone 2: The land area situated between the three hundred sixty five (365) day
groundwater travel time contour and the boundary of the zone of potential
capture for a well or well field owned or operated by the City. If the aquifer
supplying water to such a well, well field, or spring is naturally protected by
confining overlying and underlying geologic layers, the City may choose not to
subdivide a Wellhead Protection Area into two (2) zones. In such a case, the
entire Wellhead Protection Area will be designated as Zone 2 (Renton Municipal
Code 4-3-050).
d. Wellhead Protection Areas: The City may require an applicant to prepare a hydrogeologic
study if the proposal has the potential to significantly impact groundwater quantity or
quality, and sufficient information is not readily available. Such a report shall be prepared
by a qualified professional at the applicant’s expense. Report content requirements may be
specified by the City in accordance with State or Federal guidelines or tailored to the
particular development application. Peer review of the applicant’s report may be required in
accordance with this subsection F (Renton Municipal Code 4-3-050).
The are no established critical area buffers for wellhead protection zones.
EXISTING CONDITIONS
GeoEngineers reviewed the City of Renton COR Maps, King County iMap and a previous report, titled
Geologic Hazards Evaluation and Preliminary Geotechnical Engineering Services report, submitted to PSE
in December 2014, to assess existing conditions in the project area within the City of Renton
(GeoEngineers 2014). Based on information presented in that report and a review of existing maps, the
existing geology consists mainly of glacial drift, recessional outwash, glacially consolidated till and
advance outwash deposits, with the exception of localized areas of alluvium, volcanic deposits and rocks,
marine sedimentary rocks and artificial fill. Soil types anticipated in the project area include mainly silty
gravel, silty sand and silt.
Both steep sensitive slopes and protected slopes were observed locally within the project area. However,
outside of the Cedar River corridor and the Honey Dew Creek corridor, the steep sensitive slopes where
tree removal is proposed are generally developed and include rockeries, landscaped residential slopes,
and managed right-of-way areas that are unlikely to be adversely impacted based on their current
configuration and use. Protected steep slopes that include slopes of 40 percent or greater are observed
locally within the project area; however, no access roads or pole replacement activities will occur within
the mapped protected slopes. Tree removal for vegetation management purposes that is proposed on the
protected slopes occurs in the regional areas of steep slopes, namely within the Honey Dew Creek
drainage and the Cedar River drainage.
January 11, 2018 | Page 5
File No. 0186-871-06
High erosion hazard areas, sensitive and protected steep slopes, and moderate landslide hazard areas
are mapped at the Honey Dew Creek and Cedar River drainages, within the project area (City of Renton,
City of Renton COR Maps). A prehistoric, deep-seated landslide is mapped on the southern side of the
Cedar River drainage, within the project area (King County, iMap).
Moderate coal mine hazard areas also are mapped in the Cedar River drainage, within the project area
(City of Renton, COR Maps). No high coal mine hazards areas (CH) are mapped within the project site (City
of Renton, COR maps).
No high landslide hazard areas (LH) or very high landslide hazard areas (LV) are mapped within the
project site (City of Renton, COR Maps). Moderate landslide hazards are mapped locally within Honeydew
Creek and the Cedar River Valley,
High Seismic Hazards are mapped within the project corridor for a distance of approximately 470 feet
south of SR 169 within the Cedar River area in areas mapped with recent alluvial deposits.
Wellhead Protection Zones 1 and 2 are mapped within the project vicinity. An approximate 3,000-foot
segment along Monroe Avenue NE is not mapped within a wellhead protection zone. Zone 1 is located
within Cedar River corridor that includes SR 169 and Zone 2 is located in the remaining majority of the
project area.
Field Observations
A field reconnaissance was performed on June 28, 2017, to evaluate the geologic hazard areas identified
along the slopes of Honey Dew Creek and the Cedar River. The reconnaissance was divided into three
areas: Honey Dew Creek (north and south slopes), north slope of Cedar River, and south slope of
Cedar River. Our field observations are summarized as follows.
Honey Dew Creek
The project area is within an existing utility corridor with overhead power lines. Vegetation consists of
evergreen trees with bowed or pistol-butted trunks that suggest soil creep or episodic movement,
deciduous trees and an understory that includes sword fern, blackberry, salal, Oregon grape and
occasional hydrophilic plants (horsetail). Loose recessional deposits of sand and gravel are commonly
exposed at the surface within the drainage. The slope on the south side of Honey Dew Creek is inclined
between 65 to 100 percent locally. We observed two landslide scarps with 3 to 6 feet of vertical
displacement and widths of 15 to 20 feet, where exposed soils are subject to localized erosion on the
south slope, approximately 40 feet upslope of the Honey Dew Creek channel. The terrain on the slope
south of the creek is somewhat hummocky. Localized groundwater seepage and/or hydrophilic plants
were observed at an elevation approximately 10 feet upslope of Honey Dew Creek on both the south and
north slopes, where a contact between the overlying outwash deposits and an underlying laminated silt
was observed. The slope on the north side of Honey Dew Creek is commonly inclined between 60 to
70 percent, and includes a 15-foot-deep tributary drainage swale with sidewalls inclined up to
80 percent.
Cedar River North Slope
The project area within the Cedar River valley wall north slope, located north of SR 169, is within an
existing utility corridor that includes overhead power lines. Vegetation consists primarily of deciduous
January 11, 2018 | Page 6
File No. 0186-871-06
trees with occasional evergreens, and an understory that includes fern, salal, blackberry and Scotch
broom. The conifer trees are generally straight and in a vertical growth position. Loose recessional
deposits of sand and gravel are commonly exposed at the surface. The slope is inclined between 60 to
85 percent. We observed a small landslide scarp with 8 feet of vertical displacement and a width of
10 feet near the top of the slope. At mid-slope, we observed a larger arcuate landslide scarp with
approximately 15 feet of vertical displacement and a width of about 100 feet. Conifer trees near the
larger landslide commonly have bowed or pistol-butted trunks. A large hemlock tree (approximately
18 inches, diameter breast height) is growing within the landslide mass, indicating that the landslide is
relatively old. The slope also is mapped within a moderate coal mine hazard area (City of Renton, COR
MAPs), but we did not observe any evidence of land subsidence, sinkhole formation or deposits
associated with coal mining activities.
Cedar River South Slope
The project area within the Cedar River valley wall south slope, located south of the Cedar River Trail
Walk, is within an existing utility corridor that includes overhead power lines. Vegetation consists of
deciduous and evergreen trees, with a dense understory that includes fern, salal, Oregon grape,
blackberry, grass and nettles. The conifer trees are generally straight and upright, with occasional slightly
bowed trunks. Loose recessional deposits of sand and gravel are commonly exposed at the surface.
A large prehistoric, deep-seated landslide mapped by King County covers the corridor slope south of the
Cedar River. The slope is commonly inclined between 30 to 60 percent. The terrain is slightly hummocky,
but we did not observe any evidence of landslide reactivation or recent activity at the time of our site
reconnaissance. The slope is mapped within a moderate coal mine hazard area (City of Renton, COR
MAPs), but we did not observe any evidence of land subsidence or coal mining activities.
IMPACT ASSESSMENT
There are two primary ways in which tree removal activities may impact erosion and slope stability on
steep slopes or landslide hazard areas. After tree removal (where the stump is left in place), root decay
causes both the numbers of roots and the tensile strength of the remaining individual roots to decrease
with time (Burroughs and Thomas 1977). Studies show that the period of minimum root strength is
typically from 3 to 5 years after harvest (Ziemer 1981a; 1981b), but can extend up to 10 to 20 years,
depending on the tree species. For example, minimum root strength in evergreens is typically 10 years
after harvest, alders have a minimum root strength of 5 to 10 years after harvest, and maples typically
maintain full root strength after harvest. The reductions in root strength result in a net decrease in the
cohesive strength of the near-surface soil mass.
Tree removal also might modify surface and subsurface hydrology. Tree removal may increase soil
moisture by reducing canopy interception and evapotranspiration. Ground-based yarding equipment can
compact soil, which may alter hydrologic processes in certain soil types.
Elevated groundwater levels decrease the stability of slopes by reducing the shear strength of the soil and
by adding additional weight. The probability of erosion and landsliding from elevated groundwater levels
depends on the magnitude of the increase and the existing stability of the slope. The magnitude of
potential changes in groundwater levels from tree removal is highly variable and depends on several
factors, including the tree size, silviculture, subsurface conditions and topography.
January 11, 2018 | Page 7
File No. 0186-871-06
In general, tree removal will increase the potential impact on wellhead protection zones, erosion and
slope stability for erosion hazard areas, steep slopes or landslide hazard areas. Fewer impacts are
expected in areas where tree removal is isolated to one or two trees, and the erosion, steep slope or
mapped landslide hazard area is otherwise stable and well vegetated. Tree removal is not anticipated to
impact mapped moderate coal mine or high seismic hazards. Additionally, fewer impacts are expected at
the toe of the slope, compared to tree removal within the body or at the top of the slope.
Access Construction
Temporary access routes will generally follow previously established access trails and routes and, in some
cases, will cross existing developed landscape. Therefore, little cutting or filling will be required. Small
amounts of quarry spalls might be necessary to stabilize portions of existing routes. Many of the existing
routes are overgrown with vegetation and, thus, will need to be cleared. Standard erosion control best
management practices (BMPs) should be followed during construction (clearing and use of temporary
access routes). Following completion of construction activities, restoration BMPs such as mulching
and/or placing jute matting should be implemented.
Pole Installation
Where new poles are located in steep slope or landslide hazard areas, a temporary working bench might
be necessary to install the pole. These benches may vary from about 10 by 10 feet to 30 by 30 feet in
dimension. The same considerations discussed above for access routes also apply to benches needed for
pole installation. We recommend that clearing activities be restricted to that necessary to auger the hole
for the pole.
Recommendations for the design and construction of poles are presented in our Geotechnical
Engineering Services report dated June 8, 2016. In general, most of the site soils along the proposed
route consist of recessional deposits or glacially consolidated deposits, and in some limited locations,
bedrock. These soils should provide adequate support for the new poles, and it is our opinion that once
the pole is installed, the pole will not adversely impact slope stability; the pole should actually provide
additional resisting force against slope failure, provided the pole is embedded to a sufficient depth.
New poles are proposed in areas mapped as a medium/moderate coal mine hazard, which is defined in
Renton Municipal Code 4-3-050 as areas where the mine workings are deeper than 200 feet for steeply
dipping seams or deeper than 15 times the thickness of the seam or workings for gently dipping seams.
Based on the results of the subsurface soil investigation conducted in 2014 and our knowledge of the
geologic conditions in this area, the installation of new poles in these areas is not anticipated to impact
mapped moderate coal mine hazards.
Conclusions
Mapped high erosion, high seismic, sensitive and protected steep slopes and moderate or unclassified
landslide hazard areas are present within the project area. Outside of the Honey Dew Creek and Cedar
River valley areas, most of the remaining areas are developed and include rockeries, landscaped
residential or commercial development slopes and cut slopes associated with roadways, and include the
following:
■ One tree removed in the managed corridor east of North 23rd Court;
January 11, 2018 | Page 8
File No. 0186-871-06
■ Multiple trees removed east of the residence at 2101 Newport Court NE;
■ One tree removed east of the residence at 3118 NE 18th Street;
■ One tree removed on the east side of the Goodwill parking lot at 3208 NE Sunset Boulevard;
■ Multiple trees removed on the east side of an existing parking lot for 3224 NE 12th Street;
■ Multiple trees removed on the east side of existing residences from 1082 to 1074 Lynnwood
Avenue NE;
■ One tree removed on the campus of the Renton Technical College; and
■ One tree removed west of the apartment complex at SE 8th Street and Harrington Place SE.
Localized areas of high erosion, sensitive and protected steep slopes, and moderate or unclassified
landslide hazard areas in the project area include the Honey Dew Creek drainage and the Cedar River
drainage, which include slopes greater than 40 percent with a 15-foot vertical elevation rise. The Cedar
River Area also includes a localized high Seismic hazard within the mapped alluvium. The project area is
within an existing right-of-way that is maintained for vegetation by PSE. The proposed removal of selected
trees in the Honey Dew Creek drainage, selected trees north of the Cedar River, and selected trees south
of the Cedar River is consistent with the management activities of the existing power line right-of-way and
is not anticipated to impact the mapped wellhead protection zones and geologic hazard areas within
these drainage areas, provided that no tracked or rubber-tired equipment is used to remove the trees, in
our opinion. Within the Cedar River corridor no trees will be removed within the shoreline/wetland areas.
The proposed removal of trees in the Honey Dew Creek drainage is located upslope of any identified
recently active slope failures and is not anticipated to exacerbate localized slope failures, in our opinion.
Conceptual Impact Mitigation Strategy
Vegetation Management and Tree Removal
For vegetation management and tree removal in the City of Renton within the mapped geohazard areas
outlined in the proposed PSE project segment, GeoEngineers suggests the following options for mitigating
impacts after tree removal.
In general, to limit impacts on erosion and slope stability from vegetation management and tree removal
within steep slope and landslide hazard areas, the sites should be accessed by foot to reduce equipment
impacts. Hand cutting with chainsaws should be implemented to trim branches and remove trees.
Stumps should remain in place, but can be cut to ground level. Branches, limbs, trunks and other tree
debris should be chipped and scattered around the removal site within the right-of-way. Where chipping is
not feasible, unchipped tree debris can be scattered.
We recommend that trees are felled across the fall line and are left perpendicular to slope if they are not
chipped.
In areas where tree removal is clustered, erosion control BMPs, such as grass seeding, leaving stumps,
scattering straw, and/or replacement planting of native shrubs or small trees, should be implemented to
reduce concentrated flows and minimize disturbance.
January 11, 2018 | Page 9
File No. 0186-871-06
In areas where houses are located within 25 to 50 feet of vegetation management and tree removal, all
tree debris should be removed from the owner’s property and communication with the property owner is
suggested to identify possible reseeding, replacement tree or shrub, or landscaping options. If agreeable
to the property owner, it is possible that the tree trunk can be cut and left below ground surface to
maintain root strength (up to 5 to 10 years, depending on tree type), and a replacement tree or shrub
may be planted near the trimmed trunk.
Within the Honey Dew Creek and Cedar River drainage areas, where erosion, moderate landslide and
steep slope hazard areas are mapped, it is recommended that tree removal be done by hand cutting with
chainsaws, stumps left in place, and tree debris scattered. Within the Honey Dew Creek drainage,
replacement planting with native shrubs is suggested to increase root strength after tree removal and to
reduce impacts within the landslide hazard area.
Reestablish Access Routes
Where vegetation clearing is required to reestablish the access on existing trails and access routes, BMPs
should be implemented; these BMPs can include, but are not limited to: outsloping road surfaces,
crowning road surfaces (where appropriate, such as at ridge tops and where roads climb gently inclined
surfaces) and installing water bars or rolling dips at regularly spaced intervals to avoid concentrating
surface water flow along the road surface. The spacing depends on the grade of the route, the soil type
present, proximity to streams and the intended use of the road (i.e., temporary or permanent).
Most, if not all, access routes will be temporary and will be abandoned following construction of the
transmission line. No temporary access roads will cross any drainages situated in geologic hazard areas.
It is the contractor’s responsibility to complete construction work safely and in accordance with applicable
local, state and federal laws. After access use is complete, where it is deemed necessary, limited
regrading of the access route is recommended to avoid concentrating surface runoff along tracks, ruts or
other potential flowpaths. Following completion of construction activities, the construction access routes
will be graded to a stable free-draining configuration, treated with appropriate erosion control measures,
such as mulching and/or placing jute matting and installation of water bars as needed to control runoff,
and seeded. If jute mat is determined a necessary BMP, the jute mat should be anchored at the upslope
and downslope ends and secured with staples per the manufacturer’s recommendations.
Pole Installation
Where a bench is required to install a pole on a steep slope or landslide hazard area, the
recommendations presented above for temporary access roads also apply for pole installation.
Appropriate erosion control BMPs should be implemented during construction, and the disturbed area
should be restored after pole installation by seeding or revegetating and covering the disturbed area with
appropriate BMPs. Soil removed from the new pole excavations should be scattered into vegetation away
from the landscaped areas. Any areas of exposed soil must be seeded and mulched (or covered with hog
fuel) to prevent transport of sediment down the steep slopes or into the seepage area during rain events.
If the work area is wet or has standing water, driving mats should be used under all equipment and all
soils should be removed from the site for off-site disposal.
For poles located in geologic hazard areas, the old poles should be cut off approximately 1 to 2 feet below
the ground surface and the remaining portion of each pole left in place. If poles installed on slopes
January 11, 2018 | Page 10
File No. 0186-871-06
steeper than 2H:1V (horizontal to vertical), they should be embedded at least 3 feet deeper than the
typical design embedment.
CODE COMPLIANCE
4-3-050 (G2) – Development Standards – Critical Area Buffers
The critical area buffer width for very high landslide hazard areas is 50 feet. Buffers are not required for
steep slopes or high or moderate landslide hazards, based on the results of a geotechnical report and/or
independent review.
Response to Code Requirement: The site does not include any mapped very high landslide hazard
areas (LV) and, as such, there are no required buffers in the project area. The proposed activities
include vegetation management and tree removal and access routes (associated with the proposed
pole replacement activities) that will be followed by mitigation measures to reduce potential impacts
to geologic hazards. These hazards include landslide and steep slope hazards. Possible mitigation
measures include a variety of BMPs to reduce potential impacts to geologic hazards in the vicinity of
neighboring properties, including plant replacement, scattering trimmed or removed tree debris, and
chipping wood to reduce potential impacts to work areas as appropriate. Removal of vegetation by
hand and/or using limited access machinery will reduce potential impacts to landslide and steep
slope hazard areas. It is our opinion that the proposed project will not require additional buffers.
There are no established critical area buffers for erosion hazard areas or coal mine hazard areas.
4-3-050 (G5f) – Development Standards for Geologically Hazardous Areas – Protected Slopes
Development is prohibited on protected slopes.
Response to Code Requirement: No development is planned. Site activities include vegetation
management and limited tree removal (associated with the pole replacement activities) within an
existing utility right-of-way. No development or grading activities will be conducted on protected
slopes. Replacement of existing utility systems are exempted, provided the work does not increase
the footprint by more than 10 percent and that restoration shall be conducted where feasible.
4-3-050 (G5g) – Development Standards for Geologically Hazardous Areas – Sensitive Slopes;
Medium, High and Very High Landslide Hazards; High Erosion Hazards
During construction, weekly on-site inspections shall be required at the applicant’s expense. Weekly
reports documenting erosion control measures shall be required
Response to Code Requirement: Site activities include vegetation management and limited tree
removal (associated with the pole replacement activities). Weekly on-site inspections and reports
documenting erosion control measures will be completed as required by the applicant.
4-3-050 (G5i(ii)) – Development Standards for Geologically Hazardous Areas – Coal Mine Hazards
Found during Construction
Any hazards found during any development activities shall be immediately reported to the Development
Services Division. Any coal mine hazards shall be mitigated prior to recommencing construction based
January 11, 2018 | Page 11
File No. 0186-871-06
upon supplemental recommendations or reports by the applicant’s geotechnical professional. During
construction, weekly on-site inspections shall be required at the applicant’s expense. Weekly reports
documenting erosion control measures shall be required
Response to Code Requirement: Any coal mine hazards found during the proposed vegetation
management and tree removal activities associated with the pole replacement activities will be
immediately reported to the Development Services Division. Any identified coal mine hazards will be
mitigated prior to recommencing any activities based upon supplemental recommendations or
reports by the applicant’s geotechnical professional. Weekly on-site inspections and reports
documenting erosion control measures will be completed by the applicant.
4-3-050 (G5d) – Development Standards for Geologically Hazardous Areas – Seismic Hazards
Found during Construction
Any hazards found during any development activities shall be immediately reported to the Development
Services Division. Any seismic hazards shall be mitigated prior to recommencing construction based upon
supplemental recommendations or reports by the applicant’s geotechnical professional. During
construction, weekly on-site inspections shall be required at the applicant’s expense. Weekly reports
documenting erosion control measures shall be required
Response to Code Requirement: No tree removal is proposed within High Seismic Hazard areas.
Any seismic hazards found during the proposed vegetation management and tree removal
activities associated with the pole replacement activities will be immediately reported to the
Development Services Division. Any identified seismic hazards will be mitigated prior to
recommencing any activities based upon supplemental recommendations or reports by the
applicant’s geotechnical professional. Weekly on-site inspections and reports documenting
erosion control measures will be completed by the applicant.
4-3-050 (G8) – Development Standards for Geologically Hazardous Areas – Wellhead Protection
Zones Found during Construction
Any potential risks to groundwater Wellhead Protection Zones found during any development activities
shall be immediately reported to the Development Services Division. Any risk to groundwater wellhead
protection zones shall be mitigated prior to recommencing construction based upon supplemental
recommendations or reports by the applicant’s geotechnical professional. During construction, weekly on-
site inspections shall be required at the applicant’s expense. Weekly reports documenting erosion control
measures shall be required
Response to Code Requirement: No construction dewatering is planned within the project area
including Wellhead Protection Zones. Spill Prevention Control and Countermeasures (SPCC) and
Temporary Erosion and Sediment Control Plans will be implemented to address potential
construction related contaminant handling associated within Wellhead Protection Zones.
Potential contaminant impacts to Wellhead Protection Zones associated with removal and
proposed vegetation management and tree removal activities associated with the pole
replacement activities will be immediately reported to the Development Services Division. Any
risks to Wellhead Protection Zones associated with the project will be mitigated prior to
recommencing any activities based upon supplemental recommendations or reports by the
January 11, 2018 | Page 12
File No. 0186-871-06
applicant’s geotechnical professional. Weekly on-site inspections and reports documenting
erosion control measures will be completed by the applicant.
LIMITATIONS
We have prepared this report for the exclusive use of PSE and their authorized agents for the Energize
Eastside project located in Renton, Washington.
The purpose of our services was to review slope stability impacts in relation to vegetation management
and tree removal in erosion, steep slope, landslide and coal mine hazard areas along the transmission
line corridor within the City of Renton. Impacts to slope stability for pile installation was evaluated in a
separate report. Where appropriate, information from the previous reports have been used in developing
our recommendations and comments presented in this report. Within the limitations of scope, schedule
and budget, our services have been executed in accordance with generally accepted practices in the field
of geotechnical engineering in this area at the time this report was prepared. No warranty or other
conditions, express or implied, should be understood.
REFERENCES
Booth, D.B., and Wisher, A. P., compilers, Geologic map of King County, Washington Pacific Northwest
Center for Geologic Mapping Studies: scale 1:100,000, 2006. Available at
http://geomapnw.ess.washington.edu/services/publications/map/data/KingCo_composite.pdf).
Burroughs, E.R. Jr, and Thomas, B.R., 1977, “Declining root strength in Douglas-fir after felling as a factor
in slope stability.” Research Paper INT-90, Ogden, Utah, U.S. Department of Agriculture, Forest
Service, Intermountain Forest and Range Experiment Station, 27 p.
City of Renton, COR Maps (http://rp.rentonwa.gov/SilverlightPublic/Viewer.html?Viewer=COR-Maps).
City of Renton, Municipal Code (http://www.codepublishing.com/wa/renton/): Title IV, Ch. 3, 4-3-050,
and Renton Ordinance 5137, Section II, part J.
City of Renton, Sensitive Areas Steep Slopes Map
(http://rentonwa.gov/uploadedFiles/Government/FIT/GIS/PDF_Files/SteepSlopes.pdf).
GeoEngineers, Inc. December 19, 2014. Geologic Hazards Evaluation and Preliminary Geotechnical
Engineering Services, File No. 0186-871-02. Prepared for Puget Sound Energy.
King County iMap (http://gismaps.kingcounty.gov/iMap/?center=-
13600520%2C6025590&scale=2256.994353&) Accessed June 30, 2017.
NRCS, National Resource Conservation Service Web Based Soil Survey, 2008.
http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx.
Washington Division of Geology and Earth Resources, Digital Report 2, Digital Geologic Maps of the
1:100,000 Quadrangles of Washington.
January 11, 2018 | Page 13
File No. 0186-871-06
Ziemer, R. R., 1981a, “Roots and stability of forested slopes” in “International Symposium on erosion and
sediment transport in Pacific rim steep lands,” 1981 January 25-31; Christchurch, New Zealand.
IAHS Publication 132 International Association of Hydrologic Sciences Press, Washington, D.C.,
pp. 341 – 361.
Ziemer, R. R., 1981b, “The role of vegetation in the stability of forested slopes” in “Proceedings,
International Union of Forestry Research Organizations XVII World Conference,” September 6-17,
1981, Kyoto, Japan. IUFRO Congress Council, pp 297-308.
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A P P E N D I X F
Mitigation Plan
11317XAPPROXIMATE PARCEL BOUNDARYWETLAND BUFFER (100-FT)APPROXIMATE WETLAND BOUNDARYPROPOSED ENHANCEMENT AREA (9,500 SF)TREE TO BE REMOVEDXEE230 CORRIDORTALBOT MITIGATION PLAN80'20'10'040'LEGENDNOT FORCONSTRUCTION1VICINITY MAP (TALBOT)PROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LM PARCEL #2023059001PARCEL #2023059003MOWED EASEMENT CORRIDORNR01NR05APPROXIMATE EDGEOF SHRUBS ANDLOW-GROWING TREES(UNMOWED AREA)OLYMPIC PIPELINESCALE: 1" = 20'SHEET INDEX1.TALBOT MITIGATION PLAN2.TALBOT PLANTING PLAN3.HONEY DEW CREEK HABITAT TREE PLAN4.PLANTING, SOIL PREP & HABITAT DETAILS5.PLANTING & MITIGATION NOTES (1 OF 2)6.PLANTING & MITIGATION NOTES (2 OF 2)TALBOTPROJECTLOCATIONPROPOSED ENHANCEMENT AREA.PREPARE SOIL PER DETAIL.F4VICINITY MAP (HONEY DEW CREEK)HONEY DEWPROJECTLOCATIONPSE RENTON MITIGATION: TALBOT AND HONEY DEW CREEK SITES
accicrdoamalacciacciaccicrdocrdocrdocrdocrdoacciacciacciacciacciamalamalamalacciacciacciamalamalamalamalamalcrdoacciaccicrdocrdocrdoamalamalamalcrdoamalamalamalamalcrdocrdocrdocrdocrdocrdocrdocrdocrdocrdocrdoacciacciacciacci acciacci
amalamalamalamalamalcrdocrdocrdocrdocrdocrdoacciacciamalamalamalacciacci amalacciAPPROXIMATE PARCEL BOUNDARYWETLAND BUFFER (100-FT)APPROXIMATE WETLAND BOUNDARYPLANT SPECIES LISTTREESSIZESPACINGQUANTITYACER CIRCINATUM / VINE MAPLE2 GAL9' O.C.25CRATAEGUS DOUGLASII / BLACK HAWTHORN2 GAL9' O.C.28AMELANCHIER ALNIFOLIA / PACIFIC SERVICEBERRY2 GAL9' O.C.25SHRUBSCORYLUS CORNUTA / BEAKED HAZELNUT1 GAL6' O.C.50MAHONIA AQUIFOLIUM / OREGON GRAPE1 GAL6' O.C.50OEMLERIA CERASIFORMUS / OSOBERRY1 GAL6' O.C.50SYMPHORICARPOS ALBUS / SNOWBERRY1 GAL6' O.C.50HOLODISCUS DISCOLOR / OCEAN SPRAY1 GAL6' O.C.50PHILADELPHUS LEWISII / MOCK ORANGE1 GAL6' O.C.50GROUNDCOVERPTERIDIUM AQUILINUM / BRACKEN FERN1 GAL24" O.C.500POLYSTICHUM MUNITUM / SWORD FERN1 GAL24" O.C.500GAULTHERIA SHALLON / SALAL1 GAL24" O.C.500accicrdoamalTALBOT PLANTING PLAN40'10'5'020'LEGENDPROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LMPARCEL #2023059001PARCEL #2023059003NR012SCALE: 1" = 10'NOT FORCONSTRUCTIONF44" WOOD CHIP MULCH RINGSPROVIDE IRRIGATION FOR FIRSTTWO SUMMERS, SEE MITIGATIONNOTESNOTES1.REMOVE INVASIVES AND PREPARE SITE. SEE SOIL PREP DETAIL.2.SEE MITIGATION NOTES, SHEETS 5 AND 6.
SSSSHSSSHSHHHHHHXXXXXXXXXXXXXXXX15381535153715341533154115681563156215641557155815811583155015711545157015531582155215511547154915541555155615591560156515661573153615461547154815441542154315391540PSE EASEMENT BOUNDARYTREES TO BE SNAGGED (8)TREES TO BE HINGE CUT (8)TREES TO REMAINSTREAM BUFFER (115' STANDARD BUFFER,EXTENDED TO TOP OF ADJACENTPROTECTED SLOPES)PROPERTY BOUNDARYSTREAM (APPROXIMATE)SHXXLEGENDPROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LM HONEY DEW CREEKH
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EHONEY DEW CREEK HABITAT TREE PLAN80'20'10'040'3SCALE: 1" = 20'NOT FORCONSTRUCTIONPARCEL #0423059035PARCEL #0423059342B4A4
NOTES:1.SEE PLAN FOR LOCATION. VERIFY FALL DIRECTION IN FIELD WITH ASSISTANCE FROM THE RESTORATION CONSULTANT.2.TREE SHALL HAVE PLIABLE WOOD AND A MAXIMUM DBH OF 15 INCHES.4.USING ONLY A BACK CUT THAT DOES NOT FULLY SEVER THE TREE’S TRUNK FROM THE STUMP, LEAVE THE FALLEN TREECONNECTED TO THE STUMP BY A “HINGE” OF BARK.5.THE LENGTH OF THE HINGE SHOULD BE 80% OF THE DBH. VERIFY WITH RESTORATION CONSULTANT BASED ON SPECIES.6.FOR LARGER DBH TREES, PENETRATE TRUNK WITH A VERTICAL PLUNGE CUT PRIOR TO HORIZONTAL BACK CUT, OR MAKE ASHALLOW NOTCH, 1-2 INCHES DEEP, ON THE SIDE OF THE TREE FACING ITS FALL DIRECTION.HORIZONTAL BACK-CUTAT HEIGHT BETWEENTHREE AND SIX FEETABOVE GROUND LINE.PUSH TREE OVEROR PULL TRUNKTOWARD CHOSENFALL DIRECTION,AND LEAVEATTACHED TOHINGE.PLUNGE CUT AND/ORNOTCH WHENAPPROPRIATE. SEENOTES BELOW.EXISTING CONDITIONSTEP ONESTEP TWO15" DBH12" WIDE HINGE(80% OF DBH)BACK CUTHINGEOPTIONAL NOTCHPLAN VIEW OF CUTHINGE-FELLED TREESSHALL BE VERIFIED BYTHE RESTORATIONSPECIALIST.SNAG NOTES:SEE TREE SNAG TABLE FOR TREES WHICH ARE TO BERETAINED AS SNAGS. ALL TREES SHOULD BE:1.SNAGS ON SITE ARE TO BE TOPPED BY CLIMBINGARBORIST TO HEIGHT AS INDIVIDUALLY CONFIRMEDON TREE INDEX TABLE.2.LEAVE TOP OF SNAG ON THE GROUND NEARBY ANDANGLE LOG PERPENDICULAR TO SLOPE.3.ONCE TOP HAS BEEN REMOVED ARBORIST IS TOMAKE A CORONET CUT TO GIVE A NATURAL BREAKAPPEARANCE.4.RETAIN ALL BRANCHES FOR PERCHES AND HABITATSTRUCTURES- DO NOT LIMB.5.LIVE TREES SHOULD BE DEADENED BY CUTTINGTWO 6” WIDE, ANGLED BANDS AROUND THE BASE OFTHE TREE WITH AN AXE OR BY MAKING TWO CUTSAROUND THE TREE WITH A CHAIN SAW TO A DEPTHOF APPROXIMATELY 1 INCH BELOW THE BARKLAYER.GIRDLE CUTALL LIMBS REMAINUPWARD BAT SLITS.MIN. 13'-0" SNAG HEIGHT,CORONET CUTOR MACHINE BREAKGROUND6"3' - 5'BAT ROOSTING SLIT NOTES1.TO MAKE BAT ROOSTING CUTS, BEGINAPPROXIMATELY 3'-0" BELOW CORONET CUT ATTOP OF SNAG. AT AN ANGLE OF 80 DEGREES TOTHE GROUND, CUT INTO TREE TRUNK WITH ANUPWARD SLANT. MAKE 3 PARALLEL CUTS,APPROXIMATELY 2'-0" DEEP.2.FACE OF BAT ROOST SLITS ARE TO FACE EASTOR SOUTH DEPENDING ON AVAILABILITY OFSUNLIGHT IN THE MORNING HOURS.3.TO DETER SPECIES SUCH AS WASPS FROMINHABITING ROOST AREAS IT IS RECOMMENDEDTHAT CUTS BE MADE TO A THICKNESS OF 3/4".80°NOTES:1. PLANTING PIT SHALL NOT BE LESS THAN (2)TIMES THE WIDTH OF THE ROOT BALL DIA.2. LOOSEN SIDES AND BOTTOMS OF PLANTING PIT3. SOAK PLANTING PIT AFTER PLANTING2X MIN DIA. ROOTBALLREMOVE FROM POT OR BURLAP & ROUGH-UPROOT BALL BEFORE INSTALLING. UNTANGLEAND STRAIGHTEN CIRCLING ROOTS - PRUNE IFNECESSARY. IF PLANT IS EXCEPTIONALLYROOT-BOUND, DO NOT PLANT AND RETURN TONURSERY FOR AN ACCEPTABLE ALTERNATIVESPECIFIED MULCH LAYER. HOLD BACK MULCHFROM TRUNK/STEMSFINISH GRADEREMOVE DEBRIS AND LARGE ROCKS FROM PLANTINGPIT AND SCARIFY SIDES AND BASE. BACKFILL WITHSPECIFIED SOIL. FIRM UP SOIL AROUND PLANT.3"3"NOTES:1.PLANT GROUNDCOVER AT SPECIFIED DISTANCEON-CENTER (O.C.) USING TRIANGULAR SPACING, TYP.2.LOOSEN SIDES AND BOTTOM OF PLANTING PIT ANDREMOVE DEBRIS3.LOOSEN ROOTBOUND PLANTS BEFORE INSTALLING4.SOAK PIT BEFORE AND AFTER INSTALLING PLANTSPECIFIED MULCH LAYER.HOLD BACK MULCH FROMSTEMSSTEP 1STEP 2STEP 3STEP 4MIN. 8"PLANTING AREA PREPARATIONSTEP 1REMOVE UNDESIRABLE SPECIES. ADDRESS COMPACTION:COMPACTION LEVELS SHOULD BE APPROPRIATE FORROOT GROWTH (75-85% PROCTOR DENSITY) OR ASOTHERWISE APPROVED BY ENGINEER. DRAINAGE RATESHALL BE BETWEEN 1 - 5 INCHES PER HOUR OR ASOTHERWISE APPROVED BY THE ENGINEER. WORK WITHINEXISTING ROOT ZONES SHALL BE DONE BY HAND.PLACE TWO (2) INCHES COMPOST.STEP 2INCORPORATE COMPOST TO AN EIGHT (8) INCH DEPTH.STEP 3INSTALL MULCH RINGS FOUR (4) INCHES DEEP.STEP 4INSTALL PLANTS.4" MULCHEXISTING2" COMPOST4"IF VEGETATION EXISTS WITHINPLANTING AREA, SPACE AT 23 XFROM STEM OF EXISTINGVEGETATION2/3 X2/3 XAREA FOR SPACING ADJUSTMENTXXXX= PLANT SPACING= PLANTNOTE:FIRST PLACE PLANTS ALONG THEPERIMETER OF THE PLANTINGAREA, AND AROUND EXISTINGVEGETATION. THEN SPACE THEREMAINDER OF THE PLANTINGS.PLANTING, SOIL PREP & HABITAT DETAILSPROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LM
4Scale: NTSCONTAINER PLANTINGEScale: NTSHINGE CUT TREEAScale: NTSSOIL PREPARATIONFScale: NTSTRIANGULAR SPACINGDScale: NTSGROUNDCOVER PLANTINGCScale: NTSSNAG TREEBSCALE: NTSNOT FORCONSTRUCTION
GENERAL NOTESQUALITY ASSURANCE1. PLANTS SHALL MEET OR EXCEED THE SPECIFICATIONS OFFEDERAL, STATE, AND LOCAL LAWS REQUIRING INSPECTION FORPLANT DISEASE AND INSECT CONTROL.2. PLANTS SHALL BE HEALTHY, VIGOROUS, AND WELL-FORMED,WITH WELL DEVELOPED, FIBROUS ROOT SYSTEMS, FREE FROMDEAD BRANCHES OR ROOTS. PLANTS SHALL BE FREE FROMDAMAGE CAUSED BY TEMPERATURE EXTREMES, LACK OREXCESS OF MOISTURE, INSECTS, DISEASE, AND MECHANICALINJURY. PLANTS IN LEAF SHALL BE WELL FOLIATED AND OFGOOD COLOR. PLANTS SHALL BE HABITUATED TO THE OUTDOORENVIRONMENTAL CONDITIONS INTO WHICH THEY WILL BEPLANTED (HARDENED-OFF).3. TREES WITH DAMAGED, CROOKED, MULTIPLE OR BROKENLEADERS WILL BE REJECTED. WOODY PLANTS WITH ABRASIONSOF THE BARK OR SUN SCALD WILL BE REJECTED.4. NOMENCLATURE: PLANT NAMES SHALL CONFORM TO FLORA OFTHE PACIFIC NORTHWEST BY HITCHCOCK AND CRONQUIST,UNIVERSITY OF WASHINGTON PRESS, 1973 AND/OR TO A FIELDGUIDE TO THE COMMON WETLAND PLANTS OF WESTERNWASHINGTON & NORTHWESTERN OREGON, ED. SARAH SPEARCOOKE, SEATTLE AUDUBON SOCIETY, 1997.DEFINITIONS1.PLANTS/PLANT MATERIALS. PLANTS AND PLANT MATERIALSSHALL INCLUDE ANY LIVE PLANT MATERIAL USED ON THEPROJECT. THIS INCLUDES BUT IS NOT LIMITED TO CONTAINERGROWN, B&B OR BAREROOT PLANTS; LIVE STAKES ANDFASCINES (WATTLES); TUBERS, CORMS, BULBS, ETC..; SPRIGS,PLUGS, AND LINERS.2.CONTAINER GROWN. CONTAINER GROWN PLANTS ARE THOSEWHOSE ROOTBALLS ARE ENCLOSED IN A POT OR BAG IN WHICHTHAT PLANT GREW.SUBSTITUTIONS1. IT IS THE CONTRACTOR'S RESPONSIBILITY TO OBTAIN SPECIFIEDMATERIALS IN ADVANCE IF SPECIAL GROWING, MARKETING OROTHER ARRANGEMENTS MUST BE MADE IN ORDER TO SUPPLYSPECIFIED MATERIALS.2. SUBSTITUTION OF PLANT MATERIALS NOT ON THE PROJECT LISTWILL NOT BE PERMITTED UNLESS AUTHORIZED IN WRITING BYTHE RESTORATION CONSULTANT.3. IF PROOF IS SUBMITTED THAT ANY PLANT MATERIAL SPECIFIED ISNOT OBTAINABLE, A PROPOSAL WILL BE CONSIDERED FOR USEOF THE NEAREST EQUIVALENT SIZE OR ALTERNATIVE SPECIES,WITH CORRESPONDING ADJUSTMENT OF CONTRACT PRICE.4. SUCH PROOF WILL BE SUBSTANTIATED AND SUBMITTED INWRITING TO THE CONSULTANT AT LEAST 30 DAYS PRIOR TOSTART OF WORK UNDER THIS SECTION.INSPECTION1. PLANTS SHALL BE SUBJECT TO INSPECTION AND APPROVAL BYTHE RESTORATION CONSULTANT FOR CONFORMANCE TOSPECIFICATIONS, EITHER AT TIME OF DELIVERY ON-SITE OR ATTHE GROWER'S NURSERY. APPROVAL OF PLANT MATERIALS ATANY TIME SHALL NOT IMPAIR THE SUBSEQUENT RIGHT OFINSPECTION AND REJECTION DURING PROGRESS OF THE WORK.2. PLANTS INSPECTED ON SITE AND REJECTED FOR NOT MEETINGSPECIFICATIONS MUST BE REMOVED IMMEDIATELY FROM SITEOR RED-TAGGED AND REMOVED AS SOON AS POSSIBLE.3. THE RESTORATION CONSULTANT MAY ELECT TO INSPECT PLANTMATERIALS AT THE PLACE OF GROWTH. AFTER INSPECTION ANDACCEPTANCE, THE RESTORATION CONSULTANT MAY REQUIRETHE INSPECTED PLANTS BE LABELED AND RESERVED FORPROJECT. SUBSTITUTION OF THESE PLANTS WITH OTHERINDIVIDUALS, EVEN OF THE SAME SPECIES AND SIZE, ISUNACCEPTABLE.MEASUREMENT OF PLANTS1. PLANTS SHALL CONFORM TO SIZES SPECIFIED UNLESSSUBSTITUTIONS ARE MADE AS OUTLINED IN THIS CONTRACT.2. HEIGHT AND SPREAD DIMENSIONS SPECIFIED REFER TO MAINBODY OF PLANT AND NOT BRANCH OR ROOT TIP TO TIP. PLANTDIMENSIONS SHALL BE MEASURED WHEN THEIR BRANCHES ORROOTS ARE IN THEIR NORMAL POSITION.3. WHERE A RANGE OF SIZE IS GIVEN, NO PLANT SHALL BE LESSTHAN THE MINIMUM SIZE AND AT LEAST 50% OF THE PLANTSSHALL BE AS LARGE AS THE MEDIAN OF THE SIZE RANGE.(EXAMPLE: IF THE SIZE RANGE IS 12" TO 18", AT LEAST 50% OFPLANTS MUST BE 15" TALL.).SUBMITTALSPROPOSED PLANT SOURCES1. WITHIN 45 DAYS AFTER AWARD OF THE CONTRACT, SUBMIT ACOMPLETE LIST OF PLANT MATERIALS PROPOSED TO BEPROVIDED DEMONSTRATING CONFORMANCE WITH THEREQUIREMENTS SPECIFIED. INCLUDE THE NAMES ANDADDRESSES OF ALL GROWERS AND NURSERIES.PRODUCT CERTIFICATES1. PLANT MATERIALS LIST - SUBMIT DOCUMENTATION TOCONSULTANT AT LEAST 30 DAYS PRIOR TO START OF WORKUNDER THIS SECTION THAT PLANT MATERIALS HAVE BEENORDERED. ARRANGE PROCEDURE FOR INSPECTION OF PLANTMATERIAL WITH CONSULTANT AT TIME OF SUBMISSION.2. HAVE COPIES OF VENDOR'S OR GROWERS' INVOICES ORPACKING SLIPS FOR ALL PLANTS ON SITE DURING INSTALLATION.INVOICE OR PACKING SLIP SHOULD LIST SPECIES BY SCIENTIFICNAME, QUANTITY, AND DATE DELIVERED (AND GENETIC ORIGIN IFTHAT INFORMATION WAS PREVIOUSLY REQUESTED).DELIVERY, HANDLING, & STORAGENOTIFICATIONCONTRACTOR MUST NOTIFY CONSULTANT 48 HOURS OR MORE INADVANCE OF DELIVERIES SO THAT CONSULTANT MAY ARRANGE FORINSPECTION.PLANT MATERIALS1.TRANSPORTATION - DURING SHIPPING, PLANTS SHALL BEPACKED TO PROVIDE PROTECTION AGAINST CLIMATE EXTREMES,BREAKAGE AND DRYING. PROPER VENTILATION ANDPREVENTION OF DAMAGE TO BARK, BRANCHES, AND ROOTSYSTEMS MUST BE ENSURED.2.SCHEDULING AND STORAGE - PLANTS SHALL BE DELIVERED ASCLOSE TO PLANTING AS POSSIBLE. PLANTS IN STORAGE MUSTBE PROTECTED AGAINST ANY CONDITION THAT IS DETRIMENTALTO THEIR CONTINUED HEALTH AND VIGOR.3.HANDLING - PLANT MATERIALS SHALL NOT BE HANDLED BY THETRUNK, LIMBS, OR FOLIAGE BUT ONLY BY THE CONTAINER, BALL,BOX, OR OTHER PROTECTIVE STRUCTURE, EXCEPT BAREROOTPLANTS SHALL BE KEPT IN BUNDLES UNTIL PLANTING AND THENHANDLED CAREFULLY BY THE TRUNK OR STEM.4.LABELS - PLANTS SHALL HAVE DURABLE, LEGIBLE LABELSSTATING CORRECT SCIENTIFIC NAME AND SIZE. TEN PERCENTOF CONTAINER GROWN PLANTS IN INDIVIDUAL POTS SHALL BELABELED. PLANTS SUPPLIED IN FLATS, RACKS, BOXES, BAGS, ORBUNDLES SHALL HAVE ONE LABEL PER GROUP.WARRANTYPLANT WARRANTYPLANTS MUST BE GUARANTEED TO BE TRUE TO SCIENTIFIC NAMEAND SPECIFIED SIZE, AND TO BE HEALTHY AND CAPABLE OFVIGOROUS GROWTH.REPLACEMENT1.PLANTS NOT FOUND MEETING ALL OF THE REQUIREDCONDITIONS AT THE CONSULTANT'S DISCRETION MUST BEREMOVED FROM SITE AND REPLACED IMMEDIATELY AT THECONTRACTOR'S EXPENSE.2.PLANTS NOT SURVIVING AFTER ONE YEAR TO BE REPLACED ATTHE CONTRACTOR'S EXPENSE.PLANT MATERIALGENERAL1. PLANTS SHALL BE NURSERY GROWN IN ACCORDANCE WITHGOOD HORTICULTURAL PRACTICES UNDER CLIMATICCONDITIONS SIMILAR TO OR MORE SEVERE THAN THOSE OF THEPROJECT SITE.2. PLANTS SHALL BE TRUE TO SPECIES AND VARIETY ORSUBSPECIES. NO CULTIVARS OR NAMED VARIETIES SHALL BEUSED UNLESS SPECIFIED AS SUCH.QUANTITIESSEE PLANT LIST ON ACCOMPANYING PLANS AND PLANT SCHEDULES.ROOT TREATMENT1.CONTAINER GROWN PLANTS (INCLUDES PLUGS): PLANT ROOTBALLS MUST HOLD TOGETHER WHEN THE PLANT IS REMOVEDFROM THE POT, EXCEPT THAT A SMALL AMOUNT OF LOOSE SOILMAY BE ON THE TOP OF THE ROOTBALL.2.PLANTS MUST NOT BE ROOT-BOUND; THERE MUST BE NOCIRCLING ROOTS PRESENT IN ANY PLANT INSPECTED.3.ROOTBALLS THAT HAVE CRACKED OR BROKEN WHEN REMOVEDFROM THE CONTAINER SHALL BE REJECTED.PLANT INSTALLATION SPECIFICATIONSMITIGATION NOTESPLANTING & MITIGATION NOTES (1 OF 2)SCALE: NTSPROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LM
5NOT FORCONSTRUCTIONTALBOT MITIGATION PLANPSE ENERGIZE EASTSIDE 230 - RENTONEXECUTIVE SUMMARYPSE'S ENERGIZE EASTSIDE PROJECT (THE PROJECT) PROPOSES TO UPGRADEEXISTING TRANSMISSION LINES IN RENTON IN ORDER TO INCREASE TRANSMISSIONSYSTEM CAPACITY TO 230KV POWER. PROJECT ELEMENTS, EXISTING CONDITIONS,MITIGATION SEQUENCING, AND PROJECT IMPACTS TO CRITICAL AREAS AREDISCUSSED IN THE CITY OF RENTON CRITICAL AREAS REPORT (RENTON CAR)PREPARED BY THE WATERSHED COMPANY, JANUARY 2019. THIS MITIGATION PLAN ISINTENDED TO REPRESENT THE MITIGATION PLAN REFERENCED IN THE RENTONCAR. IT HAS BEEN DESIGNED TO APPROPRIATELY MITIGATE FOR PROJECT IMPACTSOCCURRING IN WETLAND AND STREAM CRITICAL AREA BUFFERS AS DESCRIBED INTHE RENTON CAR AND REQUIRED BY THE RENTON MUNICIPAL CODE (RMC).PROPOSED PROJECT ACTIVITIES IMPACT WETLAND AND STREAM BUFFERS INTHREE POSSIBLE WAYS: PERMANENT IMPACTS RESULTING IN A CONVERSION TO ADEVELOPED CONDITION AS A RESULT OF POLE FOOTPRINTS, VEGETATIONCONVERSION FROM A FORESTED VEGETATION TYPE TO A SHRUB OR HERBACEOUSCOMMUNITY DUE TO VEGETATION MANAGEMENT REQUIREMENTS (CONVERSION),AND/OR TEMPORARY IMPACTS ASSOCIATED WITH CONSTRUCTION ACTIVITIES(TEMPORARY). TEMPORARY IMPACTS WILL BE RESTORED IN PLACE AFTERCONSTRUCTION WORK IS COMPLETE. CONVERSION AND PERMANENT BUFFERIMPACTS REQUIRE MITIGATION WHICH IS PRESENTED HEREIN.THE PROJECT HAS AVOIDED ALL DIRECT PERMANENT IMPACTS (FILL) TO WETLANDS,STREAMS AND STREAM BUFFERS. ONE NEW POLE WILL BE INSTALLED WITHIN AWETLAND BUFFER AND THREE REPLACEMENT POLES WILL BE INSTALLED IN THESAME LOCATION AS EXISTING POLES WITHIN A WETLAND BUFFER, BUT WITH ALARGER FOOTPRINT. TWO EXISTING TRANSMISSION POLES WILL BE REMOVEDFROM WETLAND BUFFER, RESULTING IN AN OVERALL NET INCREASE OF ONLY 68 SFOF FILL MATERIAL IN BUFFER AREAS.VEGETATION CONVERSION (TREE REMOVAL) IMPACTS OCCUR IN THE BUFFER AREAOF THREE WETLAND AND THREE STREAM FEATURES AND ARE NECESSARY TOACCOMMODATE THE NEW 230KV TRANSMISSION LINE DESIGN AND MEET FEDERALSAFETY STANDARDS.MITIGATION FOR IMPACTS IS PLANNED IN THE BUFFER OF WETLAND NRO1 IN THELOWER CEDAR RIVER SUB-BASIN (TALBOT SITE). AS DISCUSSED IN THE RENTONCAR, THIS LOCATION WAS SELECTED FOR MITIGATION ACTIVITIES BASED UPON THELOCATION OF PROJECT IMPACTS, OPPORTUNITY PRESENT, PROPERTY OWNERSHIP,PROXIMITY TO OTHER REGULATED CRITICAL AREAS, AND THE VALUE OF THEENHANCMENT TO OVERALL CRITICAL AREA FUNCTION IN THE CORRIDOR.ADDITIONALLY, SNAG CREATION IS PROPOSED IN THE BUFFER OF HONEY DEWCREEK TO MITIGATE FOR SOME IMPACTS TO HABITAT OCCURING WITHIN THE MAYCREEK SUB-BASIN.THE MINIMUM MITIGATION AREA REQUIRED, AS PRESENTED IN THE RENTON CAR IS9,461 SF. THIS WAS CALCULATED BASED ON A PERMANENT IMPACT MITIGATIONRATIO OF 1:1 AND A VEGETATION CONVERSION MITIGATION RATIO OF 0.5:1 BASEDON ECOLOGY GUIDANCE.A TOTAL AREA OF APPROXIMATELY 9,500 SF OF DEGRADED BUFFER WILL BEENHANCED ON THE TALBOT SITE. THE ENHANCEMENT AREAS INCLUDE INVASIVESPECIES REMOVAL AND INSTALLATION OF NATIVE TREES, SHRUBS, ANDGROUNDCOVER PLANTS.OVERVIEWTHE MITIGATION PLAN CONSISTS OF APPROXIMATELY 9,500 SF OF WETLAND NRO1BUFFER ENHANCEMENT ON THE TALBOT SITE, PLUS SNAG AND HINGE-CUT TREECREATION IN THE BUFFER OF HONEY DEW CREEK. THE MITIGATION PLAN INCLUDESA COMPREHENSIVE FIVE-YEAR MAINTENANCE AND MONITORING PLAN, PER RMC4-3-50.L.3. THE PLAN SPECIFIES APPROPRIATE SPECIES FOR PLANTING ANDPLANTING TECHNIQUES, DESCRIBES PROPER MAINTENANCE ACTIVITIES, AND SETSFORTH PERFORMANCE STANDARDS TO BE MET YEARLY DURING MONITORING.THESE SPECIFICATIONS AND STANDARDS WILL ENSURE THATENHANCEMENT/RESTORATION PLANTINGS WILL BE MAINTAINED, MONITORED, ANDSUCCESSFULLY ESTABLISHED WITHIN THE FIRST FIVE YEARS FOLLOWINGIMPLEMENTATION.BUFFER ENHANCEMENT WILL INCLUDE REMOVAL OF INVASIVE SPECIES,INSTALLATION OF NATIVE TREES, SHRUBS, AND GROUNDCOVER, AND CREATION OFHABITAT SNAGS AND HINGE-CUT TREES FROM SUITABLE TREES PROPOSED FORREMOVAL FROM THE HONEY DEW CREEK BUFFERTHESE MITIGATION ACTIVITIES ARE INTENDED TO INCREASE NATIVE PLANT COVER,DECREASE INVASIVE SPECIES PREVALENCE, IMPROVE NATIVE SPECIES DIVERSITY,AND PROVIDE FOOD AND OTHER HABITAT RESOURCES FOR WILDLIFE.GOALS1.ENHANCE DEGRADED CRITICAL AREA BUFFER.a.ESTABLISH DENSE AND DIVERSE VEGETATION COMMUNITIES THROUGHOUTTHE MITIGATION AREA.b.INCREASE SPECIAL HABITAT FEATURES IN BUFFER AREAS THROUGHCREATION OF HABITAT SNAGS AND HINGE-CUT TREES.PERFORMANCE STANDARDS (TALBOT SITE)THE STANDARDS LISTED BELOW WILL BE USED TO JUDGE THE SUCCESS OF THEPLAN OVER TIME. IF THE STANDARDS ARE MET AT THE END OF THE FIVE-YEARMONITORING PERIOD, THE CITY SHALL RELEASE THE PERFORMANCE BOND.1.SURVIVAL:a.100% SURVIVAL OF ALL INSTALLED WOODY VEGETATION AT THE END OF YEAR1, STARTING FROM THE DATE OF SUBSTANTIALLY COMPLETE INSTALLATION.THIS STANDARD MAY BE MET THROUGH ESTABLISHMENT OF INSTALLEDPLANTS OR BY REPLANTING AS NECESSARY TO ACHIEVE THE REQUIREDNUMBERS.b.80% SURVIVAL OF ALL INSTALLED WOODY VEGETATION AT THE END OF YEAR2. THIS STANDARD MAY BE MET THROUGH ESTABLISHMENT OF INSTALLEDPLANTS OR BY REPLANTING AS NECESSARY TO ACHIEVE THE REQUIREDNUMBERS.i.SURVIVAL BEYOND YEAR 2 IS DIFFICULT TO TRACK. THEREFORE, DIVERSITYAND COVER STANDARDS ARE PROPOSED IN PLACE OF SURVIVAL (SEEBELOW).2.NATIVE VEGETATION COVER IN PLANTED AREA:a.ACHIEVE AT LEAST 60% COVER OF NATIVE SHRUBS BY THE END OF YEAR 3.TRANSMISSION LINE-FRIENDLY NATIVE VOLUNTEER SPECIES MAY COUNTTOWARD THIS STANDARD.b.ACHIEVE AT LEAST 80% COVER OF NATIVE SHRUBS BY THE END OF YEAR 5.TRANSMISSION LINE-FRIENDLY NATIVE VOLUNTEER SPECIES MAY COUNTTOWARD THIS STANDARD.3.SPECIES DIVERSITY IN PLANTED AREAS:a.ESTABLISH AT LEAST FOUR NATIVE SHRUB SPECIES, BYYEAR 5. TRANSMISSION LINE-FRIENDLY NATIVE VOLUNTEER SPECIES MAYCOUNT TOWARD THIS STANDARD. “ESTABLISHMENT” IS CONSIDERED TO BE ATLEAST FOUR HEALTHY, INDIVIDUAL PLANTS OF A GIVEN SPECIES PRESENTWITHIN THE MITIGATION AREAS.4.INVASIVE SPECIES STANDARD: NO MORE THAN 20% COVER OF INVASIVE SPECIESIN THE PLANTING AREA IN ANY MONITORING YEAR, EXCEPT SHALL NOT EXCEED10% COVER AT THE END OF YEAR 5. INVASIVE SPECIES ARE DEFINED AS ANYCLASS A, B, OR C NOXIOUS WEEDS AS LISTED BY THE KING COUNTY NOXIOUSWEED CONTROL BOARD.
PLANTING & MITIGATION NOTES (2 OF 2)TALBOT MITIGATION NOTESMONITORING METHODSTHIS MONITORING PROGRAM IS DESIGNED TO TRACK THE SUCCESS OF THE MITIGATION SITE OVERTIME BY MEASURING THE DEGREE TO WHICH THE PERFORMANCE STANDARDS LISTED ABOVE AREBEING MET. A FIVE YEAR MONITORING PERIOD IS PROPOSED, CONSISTENT WITH THE METHODSOUTLINED IN RMC 4-3-50.L.3.PER RMC 4-3-50.L.3, SHOULD THE MITIGATION PROJECT FAIL TO MEET ESTABLISHED SUCCESSCRITERIA AT ANY POINT, THE MONITORING PERIOD SHALL BE STARTED OVER AT YEAR ONE. THEADMINISTRATOR SHALL HAVE THE AUTHORITY TO MODIFY OR EXTEND THE MONITORING PERIOD ANDREQUIRE ADDITIONAL MONITORING REPORTS FOR UP TO TEN (10) YEARS WHEN ANY OF THEFOLLOWING CONDITIONS APPLY:A.THE PROJECT DOES NOT MEET THE PERFORMANCE STANDARDS IDENTIFIED IN THE MITIGATIONPLAN;B.THE PROJECT DOES NOT PROVIDE ADEQUATE REPLACEMENT FOR THE FUNCTIONS AND VALUES OFTHE IMPACTED CRITICAL AREA;C.THE PROJECT INVOLVES ESTABLISHMENT OF FORESTED PLANT COMMUNITIES, WHICH REQUIRELONGER TIME FOR ESTABLISHMENT.MONITORING OF THE MITIGATION SITE AND ASSOCIATED MONITORING REPORTS WILL BECONDUCTED/PREPARED BY A RESTORATION SPECIALIST AND SUBMITTED TO THE CITY FOR REVIEW.1.AN AS-BUILT PLAN AND REPORT WILL BE PREPARED WITHIN 30 DAYS OF SUBSTANTIALLY COMPLETEINSTALLATION OF THE MITIGATION AREA. THE AS-BUILT PLAN WILL DOCUMENT CONFORMANCE WITHTHESE PLANS AND WILL DISCLOSE ANY SUBSTITUTIONS OR OTHER NON-CRITICAL DEPARTURES.FOR THE TALBOT SITE, THE AS-BUILT PLAN WILL ESTABLISH BASELINE PLANT INSTALLATIONQUANTITIES, PHOTO POINTS, MONITORING TRANSECTS, AND SURVEY PLOTS THAT WILL BE USEDTHROUGHOUT THE MONITORING PERIOD TO MEASURE THE PERFORMANCE STANDARDS. FOR THEHONEY DEW CREEK SITE, THE AS-BUILT SHOULD NOTE THE CREATION OF ALL HABITAT TREES, ASWELL AS ANY DEVIATIONS FROM THIS PLAN SET.2.FOR THE FIRST YEAR FOLLOWING INSTALLATION, MONITORING REPORTS SHALL BE SUBMITTEDQUARTERLY TO THE CITY FOR THE TALBOT SITE. THEREAFTER ANNUAL REPORTS FOR THE TALBOTSITE SHALL BE SUBMITTED AT THE END OF THE GROWING SEASON (YEARS 2-5). ANNUALMONITORING REPORTS WILL INCLUDE THE FOLLOWING INFORMATION:a.SUMMARY OF PREVIOUS/SPRING VISITS.b.PLANT SURVIVAL AND/OR MORTALITY IN MITIGATION AREAS.c.CALCULATION OF NATIVE SPECIES COVER IN SURVEY PLOTS USING THE POINT-FRAME METHODAND ALONG TRANSECTS USING THE LINE-INTERCEPT METHOD.d.ESTIMATES OF NATIVE SPECIES COVER SITE WIDE.e.INVASIVE SPECIES COVER AT SURVEY PLOTS AND ALONG TRANSECTS AND ESTIMATED SITEWIDE.f.COUNTS OF ESTABLISHED NATIVE SPECIES TO DETERMINE SPECIES RICHNESS.g.PHOTOGRAPHIC DOCUMENTATION AT PERMANENT PHOTOPOINTS.h.INTRUSIONS INTO THE PLANTING AREAS, EROSION, VANDALISM, TRASH, AND OTHER ACTIONSDETRIMENTAL TO THE OVERALL HEALTH OF THE MITIGATION AREAS.i.RECOMMENDATIONS FOR MAINTENANCE IN THE MITIGATION AREAS.j.RECOMMENDATIONS FOR REPLACEMENT OF ALL DEAD OR DYING PLANT MATERIAL WITH SAMEOR LIKE SPECIES AND NUMBER AS ON THE APPROVED PLAN.3.SPRING MONITORING IS RECOMMENDED EARLY IN EACH GROWING SEASON IN YEARS 2 THROUGH 5TO NOTIFY THE OWNER AND/OR MAINTENANCE CREWS OF NECESSARY EARLY SEASONMAINTENANCE. RECOMMENDATIONS WILL BE ISSUED IN A SPRING MEMO AND WILL NOT BESUBMITTED TO THE CITY.CONSTRUCTION NOTES AND SPECIFICATIONSGENERAL NOTESTHE RESTORATION SPECIALIST WILL OVERSEE THE FOLLOWING:1.TREE SNAGGING AND HINGE-CUTTING.2.INVASIVE WEED CLEARING AND SITE PREPARATION; AND3.PLANT MATERIAL INSPECTION.a.PLANT DELIVERY INSPECTION.b.50% PLANT INSTALLATION/LAYOUT INSPECTION.c.100% PLANT INSTALLATION INSPECTION.WORK SEQUENCE1.HABITAT FEATURE CREATION:a.SNAG DESIGNATED TREES ACCORDING TO PLAN DETAIL B, SHEET 4, AND CONSISTENT WITHRECOMMENDATIONS IN THE ASSOCIATED GEOTECHNICAL REPORT.i. TREES SHOULD BE ACCESSED BY FOOT.ii. SNAG TOPS SHOULD BE PLACED PERPENDICULAR TO THE SLOPE, OR ROUGHLY PARALLEL TOTHE SLOPE CONTOUR, IN A STABLE POSITION.iii. REMAINING TREE DEBRIS SHOULD BE SCATTERED UPSLOPE OF THE BUFFER AREA NEARBY.b.HINGE-CUT DESIGNATED TREES ACCORDING TO PLAN DETAIL A, SHEET 4.2.CLEAR THE PLANTING AREA OF ALL INVASIVE WOODY VEGETATION INCLUDING BUT NOT LIMITED TOHIMALAYAN BLACKBERRY. PULL OTHER HERBACEOUS INVASIVE VEGETATION AS ENCOUNTERED(E.G., REED CANARYGRASS, HERB ROBERT).3.INSTALL EROSION CONTROLS SUCH AS WATTLES OR JUTE MAT AS DETERMINED NECESSARY INCOORDINATION WITH GEOTECHNICAL CONSULTANT.4.PREPARE SOIL PER DETAIL F, SHEET 4.5.INSTALL PLANTING AREAS:a.LAYOUT VEGETATION TO BE INSTALLED PER THE PLANTING PLAN AND PLANT SCHEDULE WITHCONSIDERATION OF PLANT SPECIES GROWING CONDITIONS.b.PREPARE A PLANTING PIT FOR EACH PLANT AND INSTALL PER THE PLANTING DETAILS. INSTALLPLANTS DURING DORMANT SEASON (OCTOBER 15TH/ TO MARCH 15TH/).c.MULCH EACH PLANT WITH A CIRCULAR WOOD CHIP MULCH RING, 4 INCHES THICK ANDEXTENDING 9 INCHES FROM THE BASE OF THE PLANT (18-INCH DIAMETER). IF THERE ARE LOTS OFINVASIVE PLANTS REMOVED, BLANKET MULCH THE AREA. MAINTAIN THREE INCH GAP BETWEENMULCH AND PLANT STEM.d.SCHEDULE WATERING TRUCK TO PROVIDE AT LEAST ONE INCH OF WATER PER WEEK, ASNECESSARY, FROM JUNE 1ST/ TO SEPTEMBER 30TH/ FOR AT LEAST TWO SUMMERS AFTER INITIALPLANT INSTALLATION. ALTERNATIVE WATERING METHODS (E.G., GATOR BAGS) MAY BE UTILIZEDWITH APPROVAL FROM THE RESTORATION SPECIALIST.MAINTENANCEMITIGATION PLAN AREAS SHALL BE MAINTAINED FOR FIVE YEARS FOLLOWING COMPLETION OF THEINITIAL PLANT AND SEED INSTALLATION.1.ROUTINE MAINTENANCE OF TALBOT PLANTING AREAS:a.AT LEAST TWICE YEARLY, REMOVE BY HAND ALL COMPETING WEEDS AND WEED ROOTS FROMBENEATH EACH INSTALLED PLANT AND ANY DESIRABLE VOLUNTEER VEGETATION TO A DISTANCEOF 12 INCHES FROM THE MAIN PLANT STEM. WEEDING SHOULD OCCUR AS NEEDED DURING THESPRING AND SUMMER. FREQUENT WEEDING WILL RESULT IN LOWER MORTALITY AND LOWERPLANT REPLACEMENT COSTS.b.DO NOT WEED THE AREA NEAR THE PLANT BASES WITH STRING TRIMMER (WEED WHACKER).NATIVE WOODY PLANTS ARE EASILY DAMAGED OR KILLED, AND WEEDS EASILY RECOVER AFTERTRIMMING.c.DURING REGULAR WEED MAINTENANCE EFFORTS (FOCUSED AROUND INSTALLED VEGETATION),ALSO GRUB OUT ANY INVASIVE SPECIES PRESENT IN DESIGNATED MITIGATION AREAS ANDREMOVE FROM THE SITE.d.APPLY SLOW-RELEASE, PHOSPHOROUS-FREE, GRANULAR FERTILIZER TO EACH INSTALLEDPLANT ANNUALLY IN THE SPRING (BY JUNE 1) OF YEARS 2 THROUGH 5.e.MULCH THE WEEDED AREAS BENEATH EACH PLANT WITH WOOD CHIP MULCH AS NECESSARY TOMAINTAIN A MINIMUM 4-INCH-THICK, 18-INCH-DIAMETER MULCH RING.f.ENSURE PLANTS RECEIVE A MINIMUM OF ONE INCH OF WATER PER WEEK, AS NEEDED, FROMJUNE 1ST/ THROUGH SEPTEMBER 30TH/ FOR THE FIRST TWO YEARS FOLLOWING INSTALLATION.THE MOST FEASIBLE IRRIGATION OPTION FOR THE SITE IS EXPECTED TO BE USE OF A WATERINGTRUCK. IRRIGATION BEYOND THE SECOND YEAR MAY BE NEEDED BASED ON SITE PERFORMANCEOR SIGNIFICANT REPLANTING.g.FOLLOW ADDITIONAL RECOMMENDATIONS NOTED IN THE SPRING OR ANNUAL MONITORING SITEVISIT.h.AS DIRECTED, INSTALL REPLACEMENT PLANTS DURING THE UPCOMING DORMANT SEASON(OCTOBER 15TH/ TO MARCH 15TH/) TO ENSURE AN 80% SURVIVAL RATE.CONTINGENCY PLANPER RMC 4-3-050.L.2,. A SURETY DEVICE IS REQUIRED TO ENSURE THE APPLICANT'S COMPLIANCE WITHTHE TERMS OF THE MITIGATION AGREEMENT. THE DEVICE SHALL MEET THE REQUIREMENTS SETFORTH IN RMC 4-3-050.L.2.MATERIALS1.COMPOST: SHALL MEET WSDOT STANDARDS SPECIFICATIONS FOR ROAD, BRIDGE, AND MUNICIPALCONSTRUCTION, 9-14.4(8) FOR FINE COMPOST.2.FERTILIZER (FOR NEAR AQUATIC ENVIRONMENTS): SLOW-RELEASE, PHOSPHOROUS-FREEGRANULAR FERTILIZER. LABEL MUST INDICATE THAT PRODUCT IS SAFE FOR AQUATICENVIRONMENTS. FOLLOW MANUFACTURER'S INSTRUCTIONS FOR USE. KEEP FERTILIZER INWEATHER-TIGHT CONTAINER WHILE ON-SITE. FERTILIZER IS ONLY TO BE APPLIED IN YEARS TWOAND THREE, NOT IN YEAR ONE.3.RESTORATION SPECIALIST: THE WATERSHED COMPANY [(425) 822-5242] PERSONNEL OR OTHERPERSON QUALIFIED TO EVALUATE ENVIRONMENTAL RESTORATION PROJECTS.4.WOOD CHIP MULCH: "ARBORIST CHIPS" (CHIPPED WOODY MATERIAL) APPROXIMATELY ONE TOTHREE INCHES IN MAXIMUM DIMENSION (NOT SAWDUST). THIS MATERIAL IS COMMONLY AVAILABLEIN LARGE QUANTITIES FROM ARBORISTS OR TREE-PRUNING COMPANIES. MULCH SHALL NOTCONTAIN APPRECIABLE QUANTITIES OF GARBAGE, PLASTIC, METAL, SOIL, AND DIMENSIONALLUMBER OR CONSTRUCTION/DEMOLITION DEBRIS.PROJECT MANAGER: DESIGNED: DRAFTED: CHECKED:SHEET SIZE:ORIGINAL PLAN IS 22" x 34".SCALE ACCORDINGLY.BY© Copyright- The Watershed CompanyDATE PRINTED BY FILENAME THEWATERSHEDCOMPANYS c i e n c e & D e s i g n750 Sixth Street SouthKirkland WA 98033p 425.822.5242www.watershedco.comJOB NUMBER:SHEET NUMBER:SUBMITTALS & REVISIONS
DESCRIPTIONDATENO.PSE RENTON MITIGATION
MITIGATION PLAN
PREPARED FOR: PUGET SOUND ENERGY
ENERGIZE EASTSIDE
PARCEL # 2023059001, 0423059342, 0423059035
RENTON, WA 98055JCLMLMJC/MF111103.11OF 61 01-08-2018 MITIGATION PLAN LM
6SCALE: NTSNOT FORCONSTRUCTION