05-140 mize-yokey rev2 20060816092105.pdfSTORM DRAINAGE ANALYSIS
Date: July 25, 2006
Prepared for
MIZE & YOCKEY RESIDENCE
22604 95th PL SW
Edmonds, Washington
Project No. S-06-140
Prepared by
MRK ENGINEERING PLLC
14218 -SE 10th Street
Bellevue, WA 98007
(206) 799-1379
34878
0
ISTE
�SSIONAL S
EXPIRES DECEMBER 02, 2006
P -J
POST—DEVELOPMENTAL FLOWS
Summary of Hydrological Parameters for Proposed Project Area:
LAND COVER
Lawn, Landscaped Areas
Impervious (asphalt, cone.,
roof top)
Total
AREA IN ACRES
0.235
0.179
0.414
%Impervious surface (Project Site
Soil Type
Hydrologic Soil Group
Time of concentration
Onsite/Collection Area:
CN VALUE
86
98
33.3
Alderwood
13.2
CONDITION IOYR FLOW 100YR FLOW
(CFS) (CFS)
Peak runoff rate 0.1182 0.2087
Is]
5. SUMMARY OF FLOW AND PROPOSED TANK PARAMETERS
Collection Area:
The final allowable discharge rates out of the detention system have been determined.
10
CONDITION 10 -YR FLOW 100 -YR FLOW », r
(CFS) (CFS)
0.1182 0.2087 63
Proposed Peak Runoff
3
(onsite)
Allowable release rater 0.0231 0.0641,
CONTROL STRUCTURE / ORIFICE AND WEA 40 FT.
Required tank length Z 30 -inch
Required tank Diameter -4
r 7 -i dia.
Bottom orifice
`� 1.64 -inch dia.
Second orifice ((a, 1.86')
The required storage quantities shown above we taken from the retults of the RLPool
Data computer model runs.