0144_001.pdfne
OMEGA
ENGINEERING INC.
January 23, 2019
City of Edmonds
Engineering Division
JoAnne Zulauf
Zachary Richardson
RE: Plan Review Comments — Dolan Addition BLD20180613
Dear Staff,
2707 Wetmore Avenue
Everett, WA 08201
t 425.387.3820
f 425.259_1958
This letter is intended to summarize the changes made to the engineering package based on
the comments the City provided in their comment documents dated 11/21/18. This letter
addresses comments from the Engineering Division which were provided via email. I have tried
to format this letter to match the comment letter for easier understanding.
Review Comments:
1. a. No new comment or request for information.
b. The updated drainage report walks through each of the BMPs included in the City of
Edmonds Addendum — Appendix A. In Section 7 of the drainage report each BMP is
discussed regarding feasibility. The list of BMPs was kept in the same order as those
provided in the Addendum and the first BMP that was determined to be feasible was
selected and implemented and any BMPs below that item in the list were not considered
since a higher BMP must be utilized if deemed feasible and no further mitigation is
required for that surface.
Detention would be feasible for this project but since higher BMPs on the list have been
utilized detention is not selected for this project. Once a surface is mitigated using the
highest available BMP on the list no further mitigation is required and no further
consideration of lower BMPs is justified.
2. a. & b. Notes have been added to the plans to connect all existing and proposed roof
downspouts to the perforated stubout connection proposed for this project.
9. The drainage design for this project no longer proposes discharging runoff to the toe of
the slope north of the SFR but rather will utilize a perforated stubout connection for roof
runoff and sheet flow dispersion for driveway runoff that is then collected by a shallow
ditch/swale and connected to a yard drain. All runoff is then conveyed to the new storm
RESUB
JAN [ 8 2019
OMEGA
ENGINEERING, INC.
2707 Wetmore Avenue
Everett, WA 98209
t 425.387.3820
f 425.259.1958
conveyance system within the Homeland Dr R/W. Therefore, a floatable separator is not
necessary for the selected BMPs and discharge location.
10. The dispersion tee has been removed from this design.
Thank you for taking the time to review the revised plans and report for this project. Please feel
free to contact me with any questions you may have.
Sincerely,
Joseph Smeby, P.E.