HomeMy WebLinkAboutEx16_Secondary_Transportation_Review_Comments
12131 113th Avenue N.E., Suite 203, Kirkland, WA 98034 | 425.821.3665 |
TG: 1.22236.00
July 20, 2022
Clark Close
Principal Planner
City of Renton
1055 S. Grady Way
Renton, WA 98057
SUBJECT: KENNYDALE GATEWAY TRANSPORTATION IMPACT ANALYSIS REVIEW COMMENTS
Dear Mr. Close:
We have completed our independent review on behalf of the City of Renton of the June 2021 Traffic Impact Analysis (TIA)
prepared by Heffron for the Kennydale Gateway project proposal as well as the Response to Comments dated March
2022. We recommend the City require an updated TIA in response to the following review comments:
Comment 1: Page 1. Introduction and Project Description. Provide context within the introduction including detail of N
44th Street southbound on-ramp. Also provide a site vicinity map to orient the reviewer to the site and the surrounding
transportation network.
Comment 2: Page 2. Figure 1: Site Plan. The site plan appears to include a southern access. Please identify this access
in the discussion. Also, unless this access is an emergency access, update study to include this driveway in the analysis.
Comment 3: Page 3. Horizon Year. Confirm if horizon year is still anticipated to be 2024 for the completion of the
interchange and Stride BRT. Link provided in the report now suggests a future 2026 horizon year. Update horizon year to
be consistent with current plans.
Comment 4: Page 4. Site Trip Generation (Apartments).
A. Provide support for suggested increase from current transit 7.2% to suggested 20% reduction assumed in the
analysis. Did the sound transit study include transit ridership projections at the new BRT station? What other
information can be provided to justify the 20%. We recognize it is an assumption, but more documentation to
support it should be provided.
B. Per ITE Trip Generation Handbook Flow Chart AM and PM peak hours should be estimated per the average rate
as both have R squared values less than 0.75.
Comment 5: Page 4. Site Trip Generation (Commercial).
A. Although the commercial space is unknown, averaging multiple rates for the commercial space is not
appropriate. Update to assume a singular use rate of either coffee shop or restaurant space as anticipated high
internal capture is inconsistent with a retail space. Update to include pass-by rates consistent with proposed use.
B. Internal capture as presented has no basis. Update internal capture assumptions to be consistent with ITE’s Trip
Generation Handbook methodology or remove from analysis. Note that internal capture reductions are applied to
both proposed uses (commercial and residential and not just a singular use as presented in the analysis).
Include detailed trip generation internal capture worksheets in updated anlaysis.
RECEIVED
Clark Close 07/21/2022
PLANNING DIVISION
EXHIBIT 16
DocuSign Envelope ID: AB259DAD-E1F4-4927-9B6D-D48F19435899
Mr. Clark Close
July 20, 2022
Page 2
Comment 6: Page 5. Table 2. Trip Generation. Update table per above comments.
Comment 7: Page 6. Traffic Volumes.
A. The park-and-ride lot is noted on page 1 to be constructed “likely on the east side of I-405”. Update analysis at all
study intersections accordingly. Currently the narrative indicates the trips were re-assigned assuming the park-
and-ride lot west of I-405, but the volumes don’t appear to support that, nor can we track the work.
B. Provide additional volume figures including the unadjusted volumes per the WSDOT’s analysis and show a figure
illustrating the shifts so we can review the future volumes appropriately.
C. Provide a trip distribution and assignment figure, and discussion on the assumptions and why they are consistent
or not consistent with the I-405 analysis.
Comment 8: Page 7. Figure 3. AM Peak Hour Traffic Volumes. Remove ‘X’ volume movements at the Seahawk Way
intersection. Or define what is meant my denoting an ‘X’ on the figure.
Comment 9: Pages 7 and 8. Figures 3 and 4.
A. Assignment as illustrated at the driveway in the figures suggests less than 5 percent of trips to/from the south
along Lake Washington Boulevard N. Based on a review of the assignment at the driveways in the WSDOT
study, the distribution was approximately 15-20% to/from the south along Lake Washington Boulevard N. Provide
support for difference from previous study or update analysis to be consistent with WSDOT study.
B. Update assignment to include both driveways if appropriate (see comment 2).
Comment 10: Page 8. Figure 4. Double check rounding as not all project trips are reflected in the assignment at the
driveway.
Comment 11: Page 9. Table 3. Double check assumed volumes at site per WSDOT study. Per review of Figure A4 in the
WSDOT study, there are 321 (166/155) AM peak hour trips and 323 (173/140) PM peak hour trips. Confirm and update
table as appropriate.
Comment 12: Page 9. LOS Standard. Per WSDOT’s LOS Map, this section of I-405 suggests a LOS D standard. Update
to assume LOS D.
Comment 13: Page 10. Table 4.
A. Include v/c ratios for all roundabout controlled intersections. See WSDOT sidra protocol and confirm all
parameters assumed are consistent.
B. Review operations using sidra corridor analysis to ensure closely spaced roundabouts and proximity to the
proposed roundabout for the site access is not an impact to the adjacent interchange.
Comment 14: Page 10. Operational Analysis.
A. Include a queueing analysis at all study intersections using sidra corridor analysis.
B. With updates, please also include the requested study intersection included in the response to comments.
C. Provide LOS worksheets and roundabout layouts. Note that following the submittal of LOS worksheets,
additional review of analysis parameters will be reviewed.
Comment 15: Page 10. Future Roundabout at Lake Washington Blvd N / N 43rd Street. Confirm findings on
roundabout geometry/channelization at the site access with updated operations and trip generation.
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.
DocuSign Envelope ID: AB259DAD-E1F4-4927-9B6D-D48F19435899
Mr. Clark Close
July 20, 2022
Page 3
Sincerely,
Transpo Group
Jon Pascal, PE
Principal
DocuSign Envelope ID: AB259DAD-E1F4-4927-9B6D-D48F19435899