APPROVED BLD2023-0504+Storm_Drainage_Report+4.21.2023_4.14.06_PM+3499044RAM Engineering
Memorandum
To: City of Edmonds Date: March 31, 2023
Engineering Division
From: Rob Long, PE
RAM Engineering
Subject: 23901 9111 PI W, Lot 6 Brackett's Reserve
Stormwater Memo
RAM Job No. 20-024
This memo provides a summary of the stormwater drainage control system for Lot 6 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 6
hard surface areas.
Below is a stormwater control summary table for Lot 6:
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
2,450 sf
Soil Amendments (BMP T5.13)
Roof
1,987 sf
Plat Detention Vault
Hard Surfaces
620 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
23901 91st PI W, Lot 6 Brackett's Reserve
Stormwater Memo
RAM lob No. 20-024
23901 91st PI W, Lot 6 Brackett's Reserve
Hard Surface Summary:
Roof =
1,987 sf
Driveway =
460 sf
Sidewalk/Patio =
160 sf
Total =
2,607 sf
Allowed/Allocated =
2,800 sf
INSTALL 1-1/2" PE (160 PSI) SERVICE
_
CONSTRUCT STABILIZED TEMPORARY
LINE FROM WATER METER TO HOUSE
CONSTRUCTION ENTRANCE PER CITY
OF EDMONDS S7D DWG NO ER-901
TRACER WIRE TO BE INSTALLED
WITH WATER LINE
(7" WATER SERVICE &METER 70 BE
(SEE DETAIL ON SHT GN-01)
- INSTALLED AS PART OFBRACKETT'S
RESERVE PLAT.)
DRY U77LI71ES
N69 45'00"E 100.00'
2.0A
-
CS
3
'i I
t
III
GARAGE
FF 456.50
—�
a
OR/VEWANH
460 SF
i
1,987 SF
Coof
455.4
-
D/W
4' PVC SIDE SEWER
PE
® 20S MIN SLOPE
CONNECT TO SS STUB
ROOF
.�
FC
III
2,OS
—
6
003 SF
SSCO
PROPOSED HOUSE
LOWER FF 457.00
IE 4454.Ot
4" PVC F0077NG
..
-
- INSTALLED 2' X 2' ORYWELL
W97H 3/4" TO 1-1/2" DRAIN
T
i
DR MG11LINE
ROCK FOR WALL DRAIN
CONNECTION (2' MIN DEPTH)
SDCO
-- - 455.7t
1 FGI
I
1E454.0t
— — — — — — — — — — — — — — —
4" PVC ROOF D IN N6945100"E 100.00'
TIGHTLINE 0 LO IN.
CONNECT TO SO B
-
-
-
6
- -- -
'ROW
20' R
-
E 452. Of
1o'raNr 160 SF
UTILITY EASEMENT SIDEWALK/PATIO
r
r
-
- i
INSTALL TEMPORARY SEDIMENT TRAP
FOR CATCH BASINS PER CITY OF
1
EDMONDS STD DWG NO ER-902
(SEE DETAIL ON SHT ON-01)
3
I
5
eF:gT L • l
C) of W, O�
-0 d
N5�G10NAL�
3/31/ZOZ3
Page 2 of 2
WMA
ALL ROCKERIES ARE TO BE
CONSTRUCTED AS PART OF
BRACKETT'S RESERVE PLAT
CONSTRUCTION (PLN2021-0037)
45
FM
STOCKPILE
AREA
I
II
I
I
PATIO
31.5�
�
I
I
- (TYP)
�C
11 ass
FILTER FABRIC FENCE PER
CITY OF EDMONDS STD
DWG NO.. ER-900
(SEE DETAIL ON SHT CN-01)
INSTALL FOUNDAnON/F00T7NG DRAIN
ALONG BUILDING PERIMETER F0077NCS
PER F0077NG DRAIN DETAIL BY EARTH
SOLU17ONS NW ON SHEET GN-01
RAM Engineering 1910936`1Ave W,Suite 100 Lynnwood WA 98036 (425)678-6960 RAMengineeringinc.com