HomeMy WebLinkAboutExh.43_On_Hold_Correction_LetterDecember 4, 2019
David Maul
Rutledge Maul Architects
19940 Ballinger War NE, Suite A-3
Shoreline, WA 98115
SUBJECT: "On Hold" Notice
Cedar River Apartments / LUA19-000161
Dear Mr. Maul,
The City, secondary reviewers, and agencies with jurisdiction have reviewed your submittal items and determined
that additional information is necessary in order to proceed. The following information will need to be submitted
before March 3, 2020 so that we may continue the review of the above subject application. Please include a
written narrative responding to each correction item and request for additional information by detailing how
resubmitted items satisfy the correction/request.
1.Boundary Survey – Provide a boundary survey prepared by a professional land surveyor for the subject
property. All easements shall be shown on the document.
2.Fire Flow – A 10-inch looped main is shown around the proposed building however a 12-inch main is
required to provide the 3,500 gpm fire flow needed for this project. Please update utility plans to reflect
this requirement.
3.Fire Access – The fire access roadway around the building is shown as a grasscrete type of roadway.
Regular paving or other alternative material approved by the fire authority.
4.Water Main - Ensure a minimum of 12-inches of vertical separation are maintained between the water
and all other utilities. If vertical separations cannot be met, the applicant may need to locate the water
main further to the west to avoid crossing the sewer line. Maintain adequate horizontal separation
between storm main and water main at all locations. Show locations of thrust blocks per city standard
detail 330.2
5.Disconnected Migration Area – In part, consideration for a Disconnected Migration Area for the area
identified as a Channel Migration Zone on the subject property requires “legally existing artificial
channel constraints that limit channel movement.” According to the technical memorandum prepared
by Golder Associates (pgs. 8 and 9), the shoreline stabilization on the subject property was constructed
sometime between 1985 and 2002. Please provide documentation the shoreline stabilization is legally
existing by providing local, state, and federal approvals for its construction.
6.Grading Plan – Provide clarification of existing and proposed grades within the 100-foot shoreline buffer
via a standalone grading plan for this area as Sheet W2 contains excessive line work and is difficult to
distinguish grades.
7.View Corridors – As provided in the Shoreline Master Program Regulations (RMC 4-3-090D.3.bi) and
presented in the May 18, 2017 preapplication meeting notes, where commercial, industrial, multiple use,
multi-family and/or multi-lot developments are proposed, primary structures shall provide for view
corridors between buildings where views of the shoreline are available from public right-of-way or trails.
Please provide a corridor analysis that identifies existing views and how they will be maintained post
development.
8.Shoreline Vegetated Open Space Trail – Per RMC 4-3-090D.4.d.i, trails within required vegetated open
space are limited to four to six feet and constructed of permeable materials. Shoreline Sheets W2 and W3
indicated trail widths of 10-feet with concrete features. Please revise all relevant sheets to comply with
the master program’s trail design regulations or submit a shoreline variance to be included in the master
application.
9.City Transportation Comments – Please provide responses and corrections to the following comments
from the City’s Public Works Department – Transportation Division:
a.Traffic Impact Analysis (dated 11/01/18), page 15, I-405/SR 169 Interchange Improvements, the
first paragraph should be revised to read as follows:
“There are currently two interchange projects proposed at this location. The first involves a
proposed short-term enhancement with rechannelization of the southbound on-ramp to include
two general purpose lanes (the HOV lane will be removed). Use of the shoulder when the ramp is
metered will still be allowed. Also as part of this, the westbound approach would be modified
(underneath I-405) to include two westbound left turn lanes to the southbound ramp. This would
involve rechannelization of the inside through lane to a shared thru plus left turn lane. The signal
already operates as a split phase and no timing changes are required. This concept is expected to
be completed in 2020 as it benefits to current traffic operations are substantial.”
b.The preceding revised paragraph should be reflected in the Conclusions section of the TIA.
c.Traffic Impact Analysis Supplement ( dated 5/28/19) – the analysis (of which results are
reflected in Table 3 on page 6) should be revised to reflect the above revised paragraph.
Footnote b in Table 3 should be revised accordingly.
d.Regarding the results in the AM and PM peak hour for the SR 169/Sunset/ Bronson/I-405 SB On-
ramp in Table 3, it is hard to believe that ramp metering will add 100 sec/veh over non-ramp
metering (based on results shown in Table 9 in the 11/01 TIA) with three general purpose lanes
available during ramp metering. Also, should LOS improve significantly without the HOV lane on
the southbound ramp?
10.Muckleshoot Indian Tribe Comments – Please provide responses to the enclosed comments prepared by
Karen Walter of the Tribe’s Fisheries Division.
11.Washington State Department of Ecology Comments – Please provide responses and corrections to the
environmental checklist per the enclosed comments prepared by Katelynn Piazza the department’s SEPA
Coordinator.
12.Washington State Department of Transportation Comments – Please provide responses and corrections
reflecting the enclosed comments prepared by Duffy McColloch the department’s Local
Agency/Development Services Engineer.
13.Third Party Geotechnical Review – Please provide responses, corrections, and requested analysis from the
enclosed GeoEngineers third party review of the project’s documents related the bulkhead along the
Cedar River.
14.Third Party Transportation Review – Please provide responses, corrections, and requested analysis from
the enclosed Transpo Group third party review of the Transportation Impact Analysis.
At this time, your project continues to remain “on hold” pending receipt of the requested information. The
maximum time for resubmittal shall be within ninety (90) days of this notice. Please contact me at (425) 430-6593
or mherrera@rentonwa.gov should you have any questions.
Sincerely,
Matt Herrera, AICP
Senior Planner
enc:
cc:
Muckleshoot Indian Tribe Comments prepared by Karen Walter dated August 29, 2019
Department of Ecology Comments prepared by Katelynn Piazza, dated August 28, 2019
Washington State Department of Transportation Comments prepared by Duffy McColloch, dated September 9, 2019
GeoEngineers Geotechnical Engineering Review Services prepared by Lyle Stone, dated October 28, 2019
TranspoGroup TIA Review Comments prepared by Jon Pascal, dated December 2, 2019
SRMRenton, LLC / Owner(s)
James D Rivard / Applicant
The Watershed Company / Contact
Party(ies) of Record
From: Karen Walter <KWalter@muckleshoot.nsn.us>
Sent: Thursday, August 29, 2019 3:04 PM
To: Matthew Herrera
Subject: FW: City of Renton LUA Acceptance: Cedar River Apartments, LUA19-
000161
Attachments: NOA_Project_Acceptance_190806.pdf;
ECF_SEPAChecklist_190613_V3.pdf; Site Plan.pdf
Matt,
We have reviewed the available documents for the proposed Cedar River Apartments project at 1915
Maple Valley Highway referenced above. This project is a redevelopment of the former Stoneway
concrete and gravel facility. We offer the following comments in the interest of protecting and restoring
the Tribe’s treaty-protected fisheries resources:
This project represents an opportunity to restore river processes in the Cedar River at this location that
has been significantly altered over time as documented in the Golder October 30, 2018 Shoreline
Stabilization memo for this project. Per the memo, the most “recent” activity at the site affecting river
processes is the concrete block retaining wall noted in existence as of the 2002 aerial photograph in the
memo. This raises questions:
1. Was this retaining wall fully permitted by Renton, WDFW and any federal agencies that required
permits? If no, then the wall should not be viewed as a legal structure for purposes of this
redevelopment project. It is proposed for retention without modification currently.
2. If yes, was the wall built meeting current engineering standards at the time? Has it ever needed
maintenance?
It may be desirable to keep the wall as is; however, if it does not meet current engineering and
flood control needs, it should be reconsidered. Further, it appears that the wall was intended to
be removed as part of the Site 7 restoration project (Right Bank, River Mile 1.8 to 2.15 ) from
the Lower Cedar River Chinook Salmon Habitat Restoration Assessment Habitat
Restoration Site Potential and Feasibility Analysis Report (Herrera 2015) which states:
“Enhance right bank in conjunction with Tri-Park Master Plan redevelopment to flatten
right bank to provide shallow edge habitat at range of flows, remove invasive vegetation
and armoring, and/or install LWD and bioengineered native plantings.”
See https://www.govlink.org/watersheds/8/reports/LowerCedarRestorationAssessment_FINAL%
20REPORT.pdf
Project Environmental review approach and considerations
We agree with the City’s initial assessment that this project should undergo an environmental impact
statement process. An EIS process will enable a variety of alternatives for the site, including
modifications to the existing shoreline stabilization wall, the proposed riparian plantings, and the extent,
number and location of trails in the regulated shoreline as shown in the site plan to be considered and
their environmental impacts fully considered. This is particularly true because as discussed in project
application materials, the site is in a channel migration area of the Cedar River. This project represents
an opportunity to restore some/all of the salmon habitat functions that occur in channel migration
areas. As described currently, there is only one alternative, the proposed action/site plan. An EIS would
enable a fully consideration of the river bank options identified in the Golder October 30, 2018 memo.
Now that the cement plant is gone, the time to correct the site’s impacts to the Cedar River is now. The
existing river impairments (fill, retaining wall, concrete wash ponds) confine the likely contributed to redd
scour and reduce habitat quality/quantity by coarsening the streambed substrate, and limits salmon
production. The applicant also proposes to place fill within the 100- year flood plain, where mitigation is
provided via onsite compensatory flood storage without significant modification to the shoreline and
riverine functions. It is also not clear how the proposed fill and CLOMR application will reduce
opportunities to restore the natural channel migration that would occur if not for the existing built
structures.
The project proposal appears to be inconsistent and will likely preclude the proposed Site 7 restoration
project from the Lower Cedar River Chinook Salmon Habitat Restoration Assessment 10 Habitat
Restoration Site Potential and Feasibility Analysis Report (Herrera 2015). This project and the larger
Lower Cedar River Chinook Salmon Habitat Restoration Report/plan (now part of the larger WRIA 8 plan)
were not considered in any of the project application documents we reviewed to date. As a result, the
restoration project has not been considered in the design and evaluation of project impacts. This is
another reason why an EIS should be done that could evaluate a development proposal that
accommodates the restoration project.
Existing environmental conditions
Has the site been fully evaluated to ensure there are no environmental hazards, toxics, groundwater
contamination that needs to be addressed before the site can be redeveloped? The former concrete
settling ponds still exist on site from the available photo record. Again, an EIS would help discern these
issues further and evaluate how different development alternatives would affect or be affected by these
conditions if they exist.
Stormwater Management
a. Regardless of development alternatives, we understand that any redevelopment project would be
exempt from any stormwater detention requirements and would be allowed to discharge
stormwater directly to the Cedar River. From our review of the basis of this decision in WDOE’s
Stormwater Management Manual for Western Washington, there was no biological
considerations for this decision and no evaluation of its potential impact on treaty-protected
resources, including ESA listed Chinook and Steelhead. The issue is that the stormwater will be
discharged into margin areas of the Cedar River that are important to juvenile salmon for their
health and survival. The project needs to be modified by requiring detention and enhancement of
the river habitat where the outfalls will discharge stormwater to reduce impacts from increases in
water velocities that exceed those necessary for juvenile salmon to maintain station, feed, avoid
predators, etc. and not get flushed downstream prematurely.
b. For the proposed project or any other alternative, the redeveloped site also needs to provide
enhanced treatment methods for its stormwater to reduce metals and oil discharges in
stormwater that adversely affect salmon. See
https://www.govlink.org/watersheds/8/pdf/NOAA_stormwater_research_references.pdf for a
list of references on this topic.
Artificial Lighting
The project’s artificial lighting details need to be fully discussed including how artificial lighting will be
designed/managed to avoid increasing predation risks for juvenile salmon in the Cedar River.
We appreciate the opportunity to review this Notice of Application and look forward to the City of Renton’s
responses to these concerns. We may have further comments subsequently. Please let me know if you
have any questions.
Thank you,
Karen Walter
Watersheds and Land Use Team Leader
Muckleshoot Indian Tribe Fisheries Division
Habitat Program
39015-A 172nd Ave SE
Auburn, WA 98092
253-876-3116
From: Jennifer Cisneros [mailto:JCisneros@Rentonwa.gov]
Sent: Thursday, August 15, 2019 10:52 AM
To: Karen Walter; Laura Murphy; 'separegister@ecy.wa.gov'; 'sepaunit@ecy.wa.gov';
'misty.blair@ecy.wa.gov'; 'Sepadesk@dfw.wa.gov'; 'sepacenter@dnr.wa.gov';
'Minnie.Dhaliwal@TukwilaWA.gov'; 'jgreene@kingcounty.gov'; 'steveo@newcastlewa.gov';
'andy.swayne@pse.com'; 'sepa@pscleanair.org'
Cc: Matthew Herrera
Subject: City of Renton LUA Acceptance: Cedar River Apartments, LUA19-000161
Hello,
Please see attached documents for City of Renton LUA acceptance for the following project:
Cedar River Apartments
LUA19-000161
Attached are the Notice of Application, the Site Plan, and the Environmental Checklist.
As the project progresses, more information will be available by request and through our online Public
Notice of Land Use Applications Map.
Thank you,
Jenny Cisneros | Planning Technician
City of Renton | CED | Planning Division
1055 South Grady Way | 6th Floor | Renton, WA 98057
Phone: (425) 430-6583 | Fax: (425) 430-7300 | jcisneros@rentonwa.gov
Office Hours: Tuesday – Friday 6:30am-5:00pm
STATE OF WASHINGTON
DEPARTMENT OF ECOLOGY
Northwest Regional Office 3190 160th Avenue SE Bellevue, Washington 98008-5452 (425) 649-7000
711 for Washington Relay Service Persons with a speech disability can call (877) 833-6341
August 28, 2019
Matt Herrera
Department of Community & Economic Development
City of Renton
1055 South Grady Way
Renton, WA 98057
Re: Cedar River Apartments
File# PR19-000306/LUA19-000161, Ecology SEPA# 201904660
Dear Matt Herrera:
Thank you for the opportunity to provide comments on the Cedar River Apartments. Based on
review of the State Environmental Policy Act (SEPA) checklist associated with this Project, the
Department of Ecology (Ecology) has the following comments:
Ecology recommends the following revisions to the SEPA Checklist dated June 13, 2019:
Section A, Background; Subsection 8. Add the following documents to the list of
environmental information:
Opinion on Proposed Cleanup, Stoneway Concrete Renton, 1915 Maple Valley Hwy,
Renton, WA 98055; July 19, 2018; Washington State Department of Ecology
Environmental Covenant, King County Tax Parcel 172305-9026, Stoneway Concrete
Renton, Ecology Facility ID 62244377; July 16, 2019; Recorded Document
20190716000692, King County, Washington.
Section B, Environmental Elements; Subsection 2, Water, c, Water Runoff. Section 2c of
the Environmental Covenant prohibits stormwater infiltration facilities in the restricted area
identified in Exhibit C of the Covenant, which also requires decommissioning of the three 48-
inch diameter dry wells. Revise this section of the SEPA Checklist and the associated
stormwater management design to be consistent with the Covenant.
Section B, Subsection 7, Environmental Health. Revise this sections as follows:
Matt Herrera
August 28, 2019
Page 2
1) On July 19, 2018, the Washington Department of Ecology (Ecolotgy) issued an opinion
under the Voluntary Cleanup Program that no further remedial action would be needed
for the site upon completion of the proposed cleanup action. The cleanup has been
completed will be completed upon issuance by Ecology of a Site No Further Action
opinion letter, which will include the recorded Environmental Covenant as an attachment.
2) Cleanup of existing contamination has been completed. The project development and
design is subject to the restrictions of the recorded Environmental Covenant. No other
hazards are expected.
5) Standard precautions would be taken to ensure the safety of the work crew. The
construction manager would be contacted by a crew member immediately upon discovery
of a spill. The construction manager would then ensure that the spill is cleaned up in the
manner dictated by the chemical use instructions and would contact the appropriate
authorities. The recorded Environmental Covenant includes a Confirmational
Groundwater Monitoring Plan and an Operation, Maintenance, and Contingency Plan to
assure that protective measures are implemented during the operating life of the project.
Thank you for considering these comments from Ecology. If you have any questions or would
like to respond to these comments, please contact Michael Warfel from the Toxics Cleanup
Program at (425) 649-7257 or by email at michael.warfel@ecy.wa.gov.
Sincerely,
Katelynn Piazza
SEPA Coordinator
Sent by email: Matt Herrera, mherrera@rentonwa.gov
cc: Kenny Booth, AICP
David Maul, Rutledge Maul Architects
ecc: Michael Warfel, Ecology
From: McColloch, Duffy <McCollD@wsdot.wa.gov>
Sent: Monday, September 09, 2019 8:10 AM
To: Matthew Herrera; 'Andy Loos'
Subject: RE: 1915 Maple Valley Hwy mixed use development
Attachments: SR169_MP24.84-25.00_Cedar River Apartments Supplement TIA (1).pdf;
SR169_MP24.84-25.00_Cedar River Apartments TIA (1).pdf
Please see attached and below for WSDOT comments on the TIA submitted for this project. If you have
any questions please let me know.
TIA
1. Pg. 8: Refer to the highlighted text below Table 1. Please quantify this statement or consider
deleting it.
2. Pg. 8: Please create a Table for crash severity (fatal/serious injury/no injury).
3. Pg. 9 and Pg. 11, Figure 6: The data used is 9 years old and there has been significant growth in
the region since then. Please update with recent data within the last three years to determine
peak periods for analysis.
4. Figure 5a and 5b: Please include the AM and PM Peak periods. This should be determined
using the most recent counts.
5. Pg. 13 and Pg. 14: Refer to the highlighted text below Table 4 and 5. Please quantify this
statement or consider deleting it.
6. Pg. 13: Please include the queuing for the intersections using SimTraffic.
7. Pg. 14: Refer to the highlighted text. Please quantify and include the LOS thresholds. Per the
Developer Services Manual, the LOS threshold for HSS is LOS D for Urban Areas and LOS C for
Rural Areas.
8. Pg. 15: The northbound I-405 on-ramp will also be modified by the I-405 Renton to Bellevue
project with a single general purpose metered lane and an HOV metered shoulder.
9. Pg. 16: Please include analysis and figures for future AM and PM Peak without project traffic
volumes for opening year/full build out (2023) and a six year horizon year (2029). The 2029
horizon year was selected since this is five years after the completion of the Renton to
Bellevue Widening and Express Toll Lanes. These figures are necessary to understand the
difference in operations between no build condition and with project condition. There needs
to be an analysis of the horizon year to understand project impacts on ramp terminal and
intersection operation beyond the opening year. Refer to Design Manual Chapter 1103.02.
10. Pg. 17: For the project trip generation, please consolidate and use LUC 820 - Shopping Center.
WSDOT Region Traffic accepts its use for mixed-use retail for TIAs. LUC 920 also has only one
sample and local data collection would be required. Refer to the Trip Generation Handbook
3rd Edition, Chapter 9.3.
11. Pg. 17: How was this pass-by trip rate derived? Per the Trip Generation Handbook 3rd Edition,
Chapter 10.3 states that pass by trip estimates should be derived from Appendix E or
collecting and using pertinent local data. In addition, by using LUC 820, there is already an
average pass-by trip calculated in Appendix E.
12. Pg. 18, Table 6: Were diverted trips actually used? If not, please delete. Per the Trip
Generation Handbook 3rd Edition, Chapter 10.4.2, diverted trips should only be used on
certain occasions.
13. Pg. 19: Volumes and traffic are only analyzed through 2023. There should be a 2029 horizon
year included and analyzed. Please see Comment 9.
14. Pg. 22 Table 7: Please include a queuing analysis using SimTraffic of without project and with
project conditions in the opening and horizon year.
15. Pg. 31: Please consider restricting the access to right-in right-out. Westbound left turn
movements will have to cross three lanes to enter the driveway. There is also a controlled
access at Cedar River Park Dr.
16. Pg. 31: The proposed development will generate new trips that will head to westbound SR 169
from Cedar River Park Dr. The green time for SR 169 was also reduced in the submitted
Synchro analysis to accommodate the new vehicle trips from Cedar River Park Dr. This results
to a reduced westbound SR 169 vehicle throughput. Westbound SR 169 transitions from two
lanes to three lanes before the Cedar River Park Dr intersection. The SimTraffic queuing
analysis for opening year and horizon year were not included and is required to review SR 169
operations. Without this information, as part of mitigation, please extend the outside
westbound lane 600 feet to account for the additional project trips that are displacing SR 169
traffic and to mitigate for the reduction in mainline cycle length.
TIA Supplement Report
17. Pg. 1: Please quantify instead of using “guestimate.” In Section 4, there were approximate
meter rates from observations.
18. Pg. 2: Please updated to “without.” Refer to PDF.
19. Pg. 4, Table 2 and Pg. 6, Table 3: Please provide a queuing analysis using SimTraffic.
20. Pg. 5: How were the ramp meters included in the model? Please send the Synchro/SimTraffic
model for review.
Thanks,
Duffy McColloch, 206-440-4713
Local Agency/Development Services Engineer
WSDOT – NW Region Development Services
From: Matthew Herrera <MHerrera@Rentonwa.gov>
Sent: Tuesday, August 20, 2019 12:03 PM
To: McColloch, Duffy <McCollD@wsdot.wa.gov>
Cc: 'Andy Loos' <andy@srmdevelopment.com>
Subject: RE: 1915 Maple Valley Hwy mixed use development
Is that the level of review you typically do at the land use permitting stage? The applicant will be
required to come in following the entitlement and submit full engineering plans. The developer contact
is Andy Loos and he can be reached at andy@srmdevelopment.com and 425-803-3355.
Matt Herrera, AICP
Senior Planner
City of Renton
425.430.6593
1101 South Fawcett Avenue, Suite 200
Tacoma, Washington 98402
253.383.4940
October 28, 2019
City of Renton
Community & Economic Development
1055 South Grady Way
Renton, Washington 98057-3232
Attention: Matt Herrera
Subject: Geotechnical Engineering Review Services
Cedar River Apartments
Renton, Washington
File No. 0693-084-00
INTRODUCTION
This report presents comments from our review of geotechnical engineering analyses of the proposed Cedar
River Apartments located at 1915 Maple Valley Highway in Renton, Washington. The site is located south
of Cedar River Park, southwest of Maple Valley Road, and directly north of the Cedar River. Our services are
being provided to the City of Renton Department of Community and Economic Development in accordance
with our agreement dated July 11, 2018 and executed August 2, 2018.
The proposed development will require development in an area currently designated as Channel Migration
Zone (CMZ). We understand that the owner is proposing to have the site reclassified as Disconnected
Migration Area (DMA) based on the presence of an existing concrete wall located at the riverbank. An
analysis of the stability of the wall by Terracon and DCI Engineers has been provided to the City. Our review
of the project is limited to the concrete wall and how it relates to the regulated CMZ.
DOCUMENTS REVIEWED AND REVIEW APPROACH
We reviewed the documents “Bulkhead Wall Stability Addendum” prepared by Terracon Consultants, Inc.,
dated June 10, 2019 and “Bulkhead Wall Stability Addendum” prepared by DCI Engineers, dated June 12,
2019. We provide comments on these documents below.
We also reviewed “Revised Geotechncial Engineering Report, Cedar River Apartments, Renton,
Washington” by Terracon Consultants, Inc. dated October 31, 2018 and preliminary plan sheets prepared
by KPFF Consulting Engineers and Runberg Architecture Group. These were reviewed for background
information only.
City of Renton | October 28, 2019 Page 2
File No. 0693-084-00
“Cedar River Channel Migration Study” prepared by King County Department of Natural Resources, dated
April 2015 was also reviewed to provide context as to standards used to establish the regulated CMZs and
DMAs within the system. This document states that: “A Disconnected Migration Area (DMA) is the area
located landward of an artificial structure that is likely to restrain channel migration and that meets criteria
in Washington Administrative Code 173-26-221(3)(b) and King County (2014).” The document further
states that: “An artificial structure was considered likely to restrain channel migration if its construction,
condition, and configuration are consistent with current relevant design and construction standards and if
the present channel is unlikely to migrate landward of the structure (King County 2014).”
The purpose of our review is to determine if the analyses required to establish if the existing concrete
bulkhead is likely to restrain channel migration have been performed with current relevant design
standards. We have not not evaluated if the structure meets the criteria in the Washington Administrative
Code or other criteria.
GEOTECHNICAL REVIEW
The following presents our review comments with regard to the geotehchnical and structural analysis:
1. Analysis for the bulkhead and its ability to restrain channel migration should be based on relevant
design guides and methods specific to riverine structures. In our opinion United States Army Corps of
Engineers (USACE) design guides provide appropriate design standards. Specific design documents
could include EM 1110-2-1418 “Channel Stability Assessment for Flood Control Projects” and
EM 1110-2-2502 “Retaining and Floodwalls”. Not all elements of these documents will be applicable.
Additionally, there might be other appropriate design guides or design methods that could also be used.
2. Analysis of the bulkhead should include an evaluation of hydraulic conditions. This evaluation should
include, at a minimum, predicted scour at the toe of the bulkhead and the effects of long-term bed
degradation or aggredation and localized bend scour. The report states that scour was not considered
and that scour is being evaluated by others. The hydraulic and scour analysis should be provided for
review and the results should be incorporated in the stability analyses as appropriate. This hydraulic
analysis should also address the length of the bulkhead and if this is sufficient to manage risk of
channel migration at the upstream and downstream ends; specifically, the potential for the river to
flank the bulkhead on the upstream end.
3. We agree with the decision to use a 100-year return period seismic event for the evaluation of the
bulkhead wall for evaluating resiliency and function as a flood or hydraulic control structure. If slope
stability or lateral spread issues will impact inhabited site structures, the appropriate International
Building Code (IBC) seismic loading must be used.
4. The concrete was modeled as a cohesive material. This assumes some tension capacity in the material
and, therefore, must assume that there are no cracks in the concrete. The concrete mass is
unreinforced and, therefore, has likely cracked due to shrinking while curing. The fact that no perched
groundwater was noted on top of the concrete is, in our opinion, evidence that the concrete, while
massive and intact at a local scale, is likely cracked on a larger scale. We believe that a cohesive soil
model can be an appropriate and conservative assumption over short distances such as when
considering potential lateral earth pressures on the bulkhead wall and locally at the toe of the wall.
However, over larger areas, such as were analyzed in the global stability analysis, cracks in the concrete
12131 113th Avenue N.E., Suite 203, Kirkland, WA 98034 | 425.821.3665 |
TG: 1.19297.00
December 2, 2019
Matt Herrera
Senior Planner
City of Renton
1055 S. Grady Way
Renton, WA 98057
SUBJECT: CEDAR RIVER APARTMENTS TRAFFIC IMPACT ANALYSIS REVIEW COMMENTS
Dear Mr. Herrera:
We have completed our independent review of the October 21, 2019 Traffic Impact Analysis (TIA) prepared by William
Popp Associates for the Cedar River Apartment project proposal on behalf of the City of Renton. We recommend the City
require an updated TIA in response to the following review comments:
Pages 3, 20, Table 6. Trip Generation. The Phasing Plan and Architectural Sheets submitted as part of the application
indicate the Medical Office building planned as part of Phase 3 will be a total of 50,000 square feet (two floors of 25,000
sqft), instead of the 25,000 square feet assumed in development of the trip generation estimates. The trip generation
estimates in Table 6 and the resulting traffic operations analyses should be updated accordingly.
Page 22. Trip Distribution. The distribution of site-generated traffic should be presented following the Policy Guidelines
for Traffic Impact Analysis for New Development, May 2013. The City’s guidelines state that the distribution should be
presented by direction as a percentage of the total site generated traffic in a graphic format. Include a trip distribution
figure to illustrate how the distribution patterns were converted into project trip assignments.
Page 23 & 24. Figure 7a & 7b. It appears that the pass-by trips were not included in the figure and the operations
analysis. The pass-by trips should appear as adjustments to the turning movement counts at the site access locations.
The analysis should be updated to account for the pass-by trips.
Page 35. Intersection LOS Analysis. The turning movement volumes for 2023 “With Project” AM and PM scenarios are
not consistent for some movements between volume graphics (Figure 8b and 9b) and the Synchro worksheets in
Appendix C.1.c and C.2.c. The Synchro and corresponding SimTraffic analysis should be updated to use consistent
turning movement volumes shown in the graphics.
Page 35. Peak Hour Factor (PHF). The PHF used in the SimTraffic analysis (1.00) is not consistent with the Synchro
analysis (0.90). The WSDOT Synchro & SimTraffic Protocol, August 2018, referenced in this analysis only provides
guidance on reasonable range of the PHF to use for the Synchro analysis, with no direction for SimTraffic. Without PHF
provided for the existing turning movement counts, the future PHF could be estimated based on Table 19 from NCHRP
Report 599. The 0.90 PHF should be justified for use in the analysis, or the PHF should be updated to use recommended
values from NCHRP Report 599. Additionally, the SimTraffic analysis should utilize the same PHF as the Synchro
analysis for consistency purposes.
Page 38. SimTraffic Simulation Period. The analysis uses a 30-minute simulation rather than a commonly used 60-
minute duration as representation of the peak hour. The SimTraffic analysis should be updated to use a 60-minute period.
Mr. Matt Herrera
December 2, 2019
Page 2
Page 38. Table 8. Scenarios Evaluated. A Year 2023 scenario with the Project, but before implementation of the
WSDOT ETL project should be evaluated in SimTraffic. The TIA should be updated to include this additional scenario in
the SimTraffic results. The updated traffic operations analysis should clearly demonstrate that the trips generated by the
Project will be able to be processed by the Cedar River Park Drive intersection during the AM peak hour when the
westbound maximum queue on SR 169 extends for nearly 4,500 feet.
Page 38. SimTraffic Files. Please provide the actual SimTraffic files so the results can be reviewed more closely.
Page 42. Parking. The parking analysis should include information from the Renton Municipal Code (RMC) that identifies
the number of stalls required for each of the proposed land uses. It should be specified that for the proposed medical
office (Building C), RMC requires 5 stalls per 1,000 net floor area. A table format is recommended to summarize and
identify the differences between the parking required by RMC, the estimated parking demand from the King County Multi-
Family Residential Parking Calculator, and the proposed parking supply. The table should include the proposed parking
supply for each land use, and note key differences from the RMC. In addition, bicycle parking should be provided with
specified minimum requirement in RMC. Finally use of the King County Multi-Family Residential Parking Calculator should
be justified as a reasonable comparison tool for this specific location.
Page 48. Frontage Improvements. The discussion should be updated to identify the specific width allocated for utilities
and landscaping behind the sidewalk. Currently no width has been identified.
Page 49. Secondary Site Access - Location. The location of the access point should be consistent with the 350 feet
described on page 45. In addition, the proposed location of this access point is where the 3-lane section of southbound
SR 169 transitions to a 2-lane facility. Drivers in the right most lane would need to pay additional attention to a vehicle in
front that may turn into the driveway, while also trying to find a gap to merge left. Locating a driveway in the vicinity could
be a potential safety issue due to the multiple vehicular movements taking place. More information should be included
about the interaction between the merging vehicles on SR 169 and the site access vehicles. Otherwise, the southbound
lane transition may need to be modified to allow for a safe transition.
Page 49. Secondary Site Access – Left-Turn Restriction. We are concerned about the proposed mountable “pork-
chop” concept as they are not always effective in preventing left-turns in or out. Was the installation of C-Curb considered
to restrict the left-turn movements at this location, or some other form of access management?
Thank you for the opportunity to assist in this review. Please do not hesitate to contact me at 425.821.3665 should you
have any questions about our comments.
Sincerely,
Transpo Group
Jon Pascal, PE, PTOE
Principal