HomeMy WebLinkAboutN_ProjectNarrative_KingCo_Tabor_Crowall&Brodell_250519_v12025_0507_rev02_projectnarrativecedarriverrightbankrevrepair.docx 1
May 7, 2025
City of Renton – Planning Division
1055 S. Grady Way
Renton, WA 98057
Subject: Project Narrative for Additional (Phase 2) Geotechnical Borings, Utility Potholing, and
Cultural Resources Exploration for the Tabor-Crowall and Brodell Revetment Repair
Project
To Whom it May Concern:
The Tabor-Crowall and Brodell Revetment Repair Project (the Project) is a repair project at the
Tabor-Crowall and Brodell revetments along the Cedar River within the City of Renton. See
Attachment 1: Tabor-Crowall Revetment Repair – Cover Sheet and Vicinity Map (Sheet 1/A-001) and
Brodell Revetment Repair - Cover Sheet and Vicinity Map (Sheet 1/B-001) for locations of the Tabor-
Crowall and Brodell revetments, respectively.
The Tabor-Crowall site is located in the southwest quarter of Section 16, Township 23 N,
Range 05 E, W.M. The Brodell site is located in the northeast quarter of Section 21, Township 23 N,
Range 05 E, W.M. All borings, potholes, and cultural resources explorations will occur within
Riverview Park, on tax parcel 162305-9033 or within SR169 right-of-way (ROW).
Previous geotechnical borings and utility potholing occurred in February 2023 for the Project under
Phase 1, but additional geotechnical borings and utility potholing are needed as the design has
been further developed. See Attachment 2 – shoreline and critical areas exemption – from those
February 2023 activities for Phase 1.
Proposed Phase 2 activities include geotechnical borings, cultural resources explorations, and utility
potholing, as described in detail below. None of the borings, explorations, or potholes will be
located below the ordinary high water mark (OHWM) of the Cedar River or within wetlands.
We request a shoreline/critical areas exemption to perform all three of these geotechnical borings
on May 22 and 23, 2025 because of the availability and scheduling of Holocene as the
geotechnical driller. Should the City of Renton not want this team to conduct the T1-24 boring (see
Attachment 1 for location) that requires a lane closure on these dates ahead of the Memorial Day
weekend, we could perform that T1-24 boring at a later date and instead focus on T2-24 and T3-
24 on these days (traffic control of SR169 not needed for T2-24 and T3-24).
Geotechnical Borings
A total of three (3) geotechnical borings are proposed as part of this Phase 2.
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One (1) of these borings is within the sidewalk along SR169 to the north of the
Cedar River. This boring requires SR169 traffic control (ID: T1-24, Sheet 3/A-101).
Two (2) of these borings are located within Riverview Park across the river from
SR169. Traffic control of SR169 is not required (ID: T2-24, Sheet 3/A-101; and ID: T3-
24, Sheet 4/A-102).
See Attachment 3: Traffic Control Plans (TCPs) for these Phase 2 activities. The TCP shows a
proposed temporary lane closure of the southernmost eastbound lane while the
geotechnical boring T1-24 right next to SR169 is performed. More information on access
and approach for this boring T1-24 is included later in this letter.
Cultural Resources Exploration
Approximately ten (10) hand-dug cultural resources explorations are needed for this
Project. The area of these explorations is along the north side of SR169 between SE 5th
Street and the parking lot for the Maplewood Golf Course.
Utility Potholing
A total of twenty-four (24) utility potholes are proposed as part of this Phase 2.
Twelve (12) of these are planned near the Tabor-Crowall revetment on the right
bank of the Cedar River on the south side, or within SR169.
Twelve (12) of these are planned near the Brodell revetment within/proximate to the
Cedar River Trail along the south side of SR169. The proposed utility pothole
locations are shown by color (storm/sewer = green, communications/power = red,
water = blue). The design team is in contact with utility owners, including: The City
of Renton, King County Wastewater Treatment Division (WTD), and Seattle Public
Utilities (SPU), in addition to owners of the electrical and telecom utilities. See the
TCP, which shows a proposed temporary lane closure while the utility potholes right
along SR169 are performed.
Per Renton Municipal Code (RMC) 4-3-050.C.3.4, site investigative work is an exempt activity within
critical areas and buffers (which include the Cedar River buffer) if the work will not disturb more
than 5% of the critical area or buffer. Impacts must also be minimized, and disturbed areas must be
restored at a 1:1 ratio. The proposed project will meet these requirements.
Per RMC 4-9-190.C. the project is an exempt activity under the Shoreline Master Program based on
the following conditions: (1) The activity does not interfere with the normal public use of surface
waters; (2) The activity will have no significant adverse impact on the environment including, but
not limited to fish, wildlife, fish or wildlife habitat, water quality, and aesthetic values; (3) The activity
does not involve the installation of a structure and upon completion of the activity the vegetation
and land configuration of the site are restored to conditions existing before the activity; (4) A
private entity seeking development authorization under the Shoreline Master Program first posts a
performance bond or provides other evidence of financial responsibility to the Planning Division to
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ensure that the site is restored to pre-existing conditions; (5) The activity is not subject to the
permit requirements of RCW 90.50.550.
These proposed activities will be conducted as follows:
1. UTILITY LOCATES: An 811 One-Call will be initiated at geotechnical boring locations, utility
potholing locations, and at locations of cultural resources hand-dug exploration locations
ahead of those activities (see items 2, 3, and 4 below). Applied Professional Services (APS)
(under contract with Jacobs) will, in parallel, perform private utility locates at these
locations, placing paint on the pavement and/or turf to mark utilities. (NOTE: These utility
locates do not require disturbance of ground surface.)
2. GEOTECHNICAL BORINGS: Holocene (geotechnical driller) will perform geotechnical
borings with the oversight of Jacobs. See the site plan for planned locations, which are all
three (3) at Tabor-Crowall. Borings will be approximately 8 inches wide. All soil will be
stockpiled adjacent to the borehole and replaced upon completion of the work.
Access, Traffic Control, Vegetation Impacts/Restoration for Geotechnical Borings:
Tabor-Crowall Cedar River right bank (sidewalk next to SR169): One (1) boring (see
Attachment 1, boring ID: T1-24) up to 80 feet in depth will be conducted within the
sidewalk next to SR169. A temporary lane closure is requested to perform this
boring of the eastbound curb lane. See attached TCP for vehicle and pedestrian
closures/detours. It is anticipated that the lane closure could be up to six (6) hours.
It is anticipated that this temporary lane closure would happen in the morning
hours and be demobilized ahead of the afternoon rush hour on SR169. Holocene
will access the location via the SR169 roadway from Riverview Park. No vegetation
will be impacted by these activities. The area will then be restored to its current
condition.
Tabor-Crowall Cedar River left bank (Riverview Park): Two (2) borings (see
Attachment 1, boring ID: T2-24 and T3-24) up to 30 feet in depth will be conducted
within Riverview Park on the left bank of the Cedar River (across the river from
SR169). A Jacobs archaeologist will be present to observe borings and note if any
cultural resources are discovered during boring activities. Holocene will access the
locations with a tracked vehicle via the Cedar River Trail railroad bridge. No Cedar
River Trail or roadway closures are required for these borings, but spotters will be
used both during borings and also during access via the Cedar River Trail.
Temporary fencing will be used during these activities and removed afterwards.
Boring locations are next to the forested riparian vegetation just south of the river.
Vegetation in this area includes Douglas fir, red alder, and Himalayan blackberry.
Minor shrub or tree pruning may be necessary for this boring, but tree removal will
not be necessary. Park users will be instructed to avoid the two nearby benches.
The area will then be restored to its current condition.
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3. UTILITY POTHOLING: APS, with the oversight of Jacobs, will perform utility potholing. See
Attachment 1 for planned locations.
Method of Potholing: Potholing will be accomplished by using one of two methods –
shallow or deep – depending on the anticipated depth of the utility:
Shallow (for storm/sewer [green], communications [red] potholes: by a vacuum
mounted on the back of small pick-up truck and the hole is typically less than 8
inches wide. All excavated material will be replaced upon completion of work. The
area will then be restored to its current condition.
Deep (for water [blue] specifically the SPU water transmission line): by hydrovac
excavation; hole is typically 8-10 inches wide. Excavated material will be replaced
with new backfill material, and removed material will be hauled and disposed of.
The area will then be restored to its current condition.
Access, Traffic Control, Vegetation Impacts/Restoration for Potholing:
Tabor-Crowall: Potholing for communications/electrical (red) will occur using a
vacuum mounted on the back of a small pick-up truck. Potholes next to SR169 will
be performed during traffic control setup per Attachment 3 (with lane closure).
Potholing for storm (green) may require opening a storm maintenance hole lid in
the travel lane; therefore, this work will also need to be performed during lane
closure. See Attachment 3 for lane closure plan and pedestrian detour/access plan.
No vegetation will be impacted by these activities. The area will then be restored to
its current condition.
Brodell: Traffic control setup will be required for potholes next to SR169 per
Attachment 3 (with lane closure). Access to the pothole locations along the Cedar
River Trail will be via the trail just to the west, from the eastbound travel lane on
SR169. This is the same access location that was used for borings and potholing at
this location in February 2023. See Attachment 3 for lane closure plan and
pedestrian detour/access plan. Minor shrub and tree pruning will be required at this
location to perform the communications (red) potholing along SR169, and possibly
some to accomplish the water (blue) potholing along the trail next to the Cedar
River. The area will then be restored to its current condition.
4. CULTURAL RESOURCES EXPLORATIONS: Jacobs will perform shallow hand-dug holes
needed to inform the cultural resources assessment. See Attachment 1 for planned
locations, all along the proposed Cedar River Trail detour, north of SR169. No traffic control
or details are required for this work. No trees or shrubs will be removed or pruned for this
work. All soil will be stockpiled adjacent to the hole and replaced upon completion of the
work.
King County Water and Land Resources (WLRD) Division has hired Jacobs as the design consultant
for this work. Subconsultants and vendors under contract with Jacobs include Herrera (permitting
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support), APS (traffic control, utility potholing), Kleinfelder (laboratory analysis of geotech boring
samples) and Holocene (geotech driller).
If you have any questions regarding this project, please contact me at lhansen@herrerainc.com or
via phone at 360.939.3755.
Sincerely,
Herrera Environmental Consultants, Inc.
Liliana Hansen, PWS
Senior Scientist
CC:
Julie Titchbourne, King County Water and Land Resources Division (WLRD)
Mark Bodnar, King County Water and Land Resources Division (WLRD)
Amy Carlson, Jacobs
Dustin Atchison, Jacobs
Jacob Rector, Jacobs
Paul Tissell, Jacobs
Attached:
1. Tabor-Crowall Revetment Repair Plans and Brodell Revetment Repair Plans
2. Certificate of Exemption from Shoreline Substantial Development Permit and Critical Areas
Regulations (for Phase 1 geotechnical borings and potholing).
3. Traffic Control Plans for Tabor-Crowell and Brodell Revetment Repair, Phase 2 Borings,
Potholing, and Cultural Resources Exploration