20160520103540.pdfiM Engineering 3
Mike Clugston AICP, Associate Planner
City of Edmonds Development Services Department i
th
1215 Aenue North
Edmonds, WA 98020 �'tilitit:lfitii1 X11
RE: SFR at 239201041h Ave W
Plan Check # BLD20160459 (BLD20141294)
Review Comment Response
RAM Job No. 15-007
Ms. JoAnne Zulauf:
July 6, 2015
This letter outlines the revisions and corrections made per your request of additional information dated April 15, 2016.
Below is a list of the comment response documents addressing your comments and request:
General
FYI: A stormwater covenant shall be provided for the infiltration facility prior to construction final. If recording of the short
plat is imminent, document will not be required.
Okay.
Sheet SP -01
1. 2. Please remove "Project Notes" section from plan sheet. The notes pertain to the short plat not this project.
Project Notes removed.
2. Add haul route.
Haul route added to vicinity map on sheet 1.
3. Under "Sewer Notes" change "city main" to "OVWSD main".
Sewer notes changed to OVWSD main.
4. The easement for the alley crossing the southeast corner of the property must be shown on this plan. The actual
easement legal docs will need to go to the council for approval and acceptance before final construction approval will be
granted for this SFR permit.
Easement call -out added to plans. Client intends to record short plat with easement included.
5. SDCOs have inverts showing a 4 ft depth. Too small for adequate access for cleaning sfr system. Please revise to type 1
cb.
Per discussions with staff, cleanouts are okay as shown.
6. Flow arrows in driveway show runoff directed to northwest corner but there is no indication of how that runoff is being
conveyed to the infiltration system.
Drainage flow arrows added to sheet 1. Runoff from the driveway area will collected in CB#3 and conveyed to
onsite infiltration system.
Sheet TP -01
7. Please review sheet for additional call outs and notes needed per earlier emails regarding tesc and protected areas.
Additional TESC items have been added to sheet 3. Additional tree protection and infiltration trench protection
added per discussions with staff.
RAM Engineering 1653113`hAve W,Suite A108 Lynnwood WA 98037 (425)678-6960 RAM enginerringinc.com
Storrriwater t °onnnze*nts, arovided by Herrera
1, WWHM2012 model output report needs to be provided to verify the following model inputs (screenshot
alone is insufficient to provide this detail):
a. Rain gage — City of Edmonds required WSDOT Region Puget East 36, Gage Everett, Precip Factor = 0.8 was
used in the evaluation; full output report added to report as requested.
b. Timestep - Standard 15 -minute time step was used; full output report added to report as requested.
c. Predeveloped conditions — Not a requirement of Small Site projects.
Evaluation of flow control duration standard- Duration Standard is not a requirement of Small Site
projects.
2. WWHM2012 modeling needs to be updated to include the following:
a. Outlet/overflow structure - current no outlet (other than infiltration) is included in the model
screenshot provided on page E-1 of the Storm Drainage Report (2/23/16); however, sheet RP -01
in the plan set shows an 8" perforated pipe and an outlet structure
No outlet/overflow structure is proposed or shown on the plans. Oil/water separator tees are
shown on sheet RP -01; these are not outlet/overflow structures. Text on CB#1 callout has been
revised to an "out" to eliminate confusion.
b. Evaluation of the flow control duration standard (Stream Protection Duration) on the Analysis
tab. Duration Standard is not a requirement of Small Site projects.
3. Page E-1 of the Storm Drainage Report (2/23/16) and sheet RP -01 (2/23/16) list "1 -1/2 -inch to 3/4 -
inch washed rock." According to the Stormwater Management Manual for Western Washington, this
should be "1-1 /2 to 1-3/4 inch washed rock."
There are several discrepancies in the DOE Manual and City of Edmonds details for infiltration trench
drain rock callout. The requested 1-1/2" to 1-3/4" specification has been revised in the report and the
plans per the City's request.
4. Typos in the Storm Drainage Report (2/23/16):
a. Page i - "pf" should be "of"
b. Page i - "t" should be removed or changed to a full word
c. Page H-1 - "Infiltratin" should be "Infiltration"
Typos have been corrected in revised report.
If there are any questions regarding the items above or the contents of the revised drawings, please contact me at your
earliest convenience; I can be reached at (425)678-6960 or RobL@RAMengineeringinc.com. We sincerely appreciate your
time and assistance.
Thank you,
Rob Long, PE
Principal
cc: Kayla Clark, c/o Select Homes, Inc.
RAM Erigineeirling 16513 Ave W, Sute A108 Lyinnwracrcl WA 98037 (425) 678-6960 VIAMleingir crrirrgiiric,ccrrn�