HomeMy WebLinkAboutECF_SEPA_Clarification_190621_v1.pdf
June 13, 2019
Matt Herrera, AICP
City of Renton
Community & Economic Development
1055 South Grady Road
Renton, WA 98057
Re: Cedar River Apartments: SEPA Clarification
The Watershed Company Reference Number: 170314
Dear Matt:
This letter relates to the Cedar River Apartments project (PRE17-000246) and
accompanies additional information intended to clarify several outstanding SEPA
concerns with the project. Specifically, based upon prior correspondence with the City,
two primary issues of concern with the project were identified – 1) traffic, and 2) channel
migration. As outlined in an April 2, 2019 letter, the City’s Environmental Review
Committee (ERC) determined that these two areas of concern were likely to result in the
issuance of a SEPA Determination of Significance (DS), requiring preparation of an
Environmental Impact Statement (EIS). As such, the applicant has commissioned
additional investigation of both outstanding concerns, a summary of which is included
in this letter. Additionally, the prior prepared SEPA Checklist has been revised to
account for this information. New documentation, submitted concurrent with this letter
includes the following:
• Traffic Impact Analysis Supplemental Report for Cedar River Apartments,
Renton, Washington, May 28, 2019 (William Popp Associates)
• Bulkhead Wall Stability Addendum, Cedar River Apartments, June 10, 2019
(Terracon Consultants, Inc.)
• Re: Bulkhead Wall Stability Addendum, June 12, 2019 (DCI Engineers)
The revised SEPA Checklist and addition prepared documentation shall constitute a
supplement to the previously submitted SEPA Checklist, pursuant to WAC 197-11-
350(4).
Cedar River Apartments
SEPA Clarification
June 13, 2019
Page 2
Traffic
ERC Concern: Proposed impacts noted in the Traffic Impact Analysis (TIA) indicate a Level of
Service (LOS) reduction following completion of the project that would fall below operational
standards of ‘D’ identified for classified arterial streets in Renton Comprehensive Plan Policy T-
48.C.1. Additionally, the TIA states that the identified LOS does not account for I-405 ramp
meters for the SR169/Sunset/Bronson/I-405 SB Ramp and SR169/I-405 NB Ramp intersections
referred to as Intersections 1 and 2 in the TIA, respectively. This omission is likely to result in a
LOS that does not reflect the actual operating conditions of the intersections. The TIA indicates
reductions in LOS for both intersections following completion of the project.
Applicant Clarification: A supplement to the original TIA has been prepared and is
included with this letter. As requested, the supplement (Traffic Impact Analysis
Supplemental Report for Cedar River Apartments, May 28, 2019 – William Popp Associates)
now factors I-405 ramp meter data into intersection analyses. Additionally, the
supplement includes ‘without project’ level of service results for all phases of proposed
development. Further, as summarized in the supplement, levels of service for analyzed
intersections are expected to be maintained or improved. Thus, no significant adverse
traffic impacts will occur.
Channel Migration
ERC Concern: Based on the Cedar River Channel Migration Study prepared by King County
Department of Natural Resources and Parks, the subject property is located within a Severe
Hazard Area of the Cedar River’s Channel Migration Zone. The study does not account for the
existing armoring located along the property’s shoreline, however submitted documents by the
applicant to date do not analyze the integrity of the wall and whether it can withstand forces of
the river’s flow over the life of the project. Additionally, the applicant’s document “Review of
Shoreline Stabilization Alternatives for the Cedar River Apartments Project” prepared by Golder
Associates recommends a combination of rigid and flexible works along the property’s river
frontage that may be in direct conflict with the City’s Shoreline Master Program Regulations.
Renton Municipal Code 4-3-090E.9.d prohibits new structural flood hazard reduction measures
within a Channel Migration Zone or floodway for new residential development.
Applicant Clarification: The referenced report by Golder Associates did not account for
the structural integrity of the existing wall. As such, additional investigation was
undertaken. Specifically, Terracon Consultants, Inc. conducted geotechnical explorations
within proximity of the existing wall (Bulkhead Wall Stability Addendum, Cedar River
Apartments, June 10, 2019). Based upon the results of this work, DCI Engineers then
completed a stability review of the wall (Re: Bulkhead Wall Stability Addendum, June 12,
2019). These efforts concluded that the existing wall includes a widespread concrete
base, that is of high strength. As such, the wall was found to be stable, with no signs of
Cedar River Apartments
SEPA Clarification
June 13, 2019
Page 3
future failure. Further, no new steps will be necessary to decrease pressures on the wall
or structurally reinforce it.
Consistent with the assessment work done by King County as part of the 2015 Cedar
River Channel Migration Study, the stable wall constitutes an artificial structure that
restrains channel migration. Therefore, although mapped as within a channel migration
zone, upland areas of the site are effectively protected from channel migration, due to
the presence of the stable wall. Thus, no significant adverse impacts will occur related to
channel migration.
Summary
The additional provided information on both of the above topics is intended to
supplement prior submitted information and seeks to further clarify these issues of
concern. As described herein, the proposed project will maintain or result in an
improvement to levels of services at analyzed intersections. Further, the existing wall
that protects the site from potential channel migration zone impacts has been deemed
stable. As such, neither issue constitutes a significant adverse impact, as defined by
WAC 197-11-794.
Thank you for your attention to this matter. Please call if you have any questions or if
we can provide you with any additional information.
Sincerely,
Kenny Booth, AICP
Senior Planner / Principal