APPROVED_BLD2023-0255+Storm_Drainage_Report+2.27.2023_3.23.59_PM+3391007RAM Engineering
RECEIVED
oMor !j
To: City of Edmonds
Engineering Division
From: Rob Long, PE
RAM Engineering
Subject: 23903 915Y PI W, Lot 5 Brackett"s Reserve
Stormwater Memo
RAM Job No. 20-024
Memorandum
Date: February 14, 2023
COMPLIES WITH APPLICABLE
CITY STORM CODE
03/15/2023
BLD2023-0255
This memo provides a summary of the stormwater drainage control system for Lot 5 of the Brackett's Reserve
Plat (PLN 2021-0037). A site -specific geotechnical evaluation recommends one stormwater BMP for the site;
BMP T5.13: Post -Construction Soil Quality and Depth based on the site's soil conditions. In accordance with
Edmonds Code, lawn and landscape areas will be managed by post -construction soil quality and depth (soil
amendments). The roof top, driveway, walk and patio areas will be managed by the Brackett's Reserve
detention vault located in Track 999 of the plat. The plat design has allocated 2,800 sf of hard surface for Lot 5
hard surface areas.
Below is a stormwater control summary table for Lot 5:
Stormwater Control Summary:
Project Site Category: Category 2 (part of the Brackett's Reserve Plat)
Discharge Location: City's Municipal Separate Storm Sewer System (MS4)
Type of Area
Square Footage
Storm water Facility
Lawn and Landscape
2,216 sf
Soil Amendments (BMP T5.13)
Roof
2,194 sf
Plat Detention Vault
Hard Surfaces
590 sf
Plat Detention Vault
(Driveway/Apron, Walk and Patio)
25% Retrofit
0 SF
None
PKAM Engineering 19109 3611 Ave W, Suite 100 Lynnwood WA 98036 (425)678-6960 RAMengineeringinc.com
23903 91st PI W, Lot 5 Brackett's Reserve Page 2 of 2
Stormwater Memo
RAM lob No. 20-024
23903 91st PI W, Lot 5 Brackett's Reserve Hard Surface Summary:
Roof = 2,194 sf
Driveway = 430 sf
Sidewalk/Patio = 160 sf
Total = 2,784 sf
Allowed/Allocated = 2,800 sf
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a CONSTRUCTION ENTRANCE PER CITY
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(SEE DET41L ON sHT Gu-01)
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INSTALL 1-1/2- (160 PSI) SERWC£
LINE FRQV WA METER TO HOUSE
FILTER FABRIC FENCE PER
OTY OF EDMONDS STD
OW NO ER-900
TRACER MIRE TO INS
W D, WATER— 160 SF
(SEE DETAIL ON SNT GN-0I)
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10' PRIVATE DRAINAGE
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INSTALLED AS PART OF SIDEWALK/PATIO
RESERVE PLAT)
INSTALL FOUNDATION/F00TING DRAIN
LOTS J h 5
ALONG BUILDING PERIMETER FOORNCS
PER FOOTING DRAIN DETAIL BY EARTH
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