SW6170901 - Oak Hill Living Center (7)

IMPERVIOUS MAPS

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—x—x—x—x x
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PRE -DEVELOPMENT IMPERVIOUS AREAS
® BUILDING AREA 41,520 SF
VEHICLE AREA 45,145 SF
NON -VEHICLE AREA 3,140 SF
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0 50 100 200 300
1 "=100'@11X17
OAK HILL LIVING CENTER
9767 NC 210
ANGIER, NORTH CAROLINA
project #: 1463-0479
BOBBITT DESIGN BUILD, INC
800 GERMANTOWN ROAD
IMP 1 �®��®�� RALEIGH, 827
PH [phone]
FX. (919)85 85 1-191982
E-MAIL d-,lgn@bcbt tLo
_ WWW BOBBITT COM
Fbm Uc 9 D-0191
CoP GHT C 2017 BOBBITT DESIGN BUILD, INC. ALL RIGHTS RESERVED.

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•
•
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POST -DEVELOPMENT IMPERVIOUS AREAS
® BUILDING AREA 51,635 SF
.'.'' VEHICLE AREA 58,465, SF
NON—VEHICLE AREA 4,780 SF
/\
0 50 100 200 300
1"=100'@11X17
OAK HILL LIVING CENTER
9767 NC 210 ,
ANGIER, NORTH CAROLINA
project #:1463-0479
BOBBITT DESIGN BUILD, INC
P2=Bo��®�� G OWN ROAD
RALEIGH(0101 aNC 47807
PH (870J 881-1880
FK [phone]
E-MAIL design@bobbft—
WWW BOBBITT COM
Flnn Lia tl D-0iB1
COPYRIGHT (C)'2017 BOBBITT DESIGN BUILD, INC. ALL RIGHTS RESERVED.

BIORETENTION POND CALCULATIONS

Bioretention Cell Calculations
Underdrain Calculation
Volume Provided (cf) = 3,094 C.F.
Drawdown Time (Pond Volume) = 6 hours
Average flow rate = Volume/Time
Q = (3,094 C.F.)/(6 hr)/(60min/hr)/(60sec/min)
Q = 0.14 cfs
Design Factor of Safety = 10
Q design = 1.4 cfs
Required Pipe Size
n=0.011
S=0.5% 3/8
D=16 jQ*nl
[ P05
D= 9.03"
Required — (3) 6" Sch. 40 PVC pipes
Provided — (3) 6" Sch. 40 PVC pipes @ 0.5% min slope (Perforated)
Cleanouts —1 per 1,000sf surface area
3,094 sf / 1,000 sf = 4 cleanouts required
8 cleanouts provided

First Flush Volume Calculations
Oak Hidd Living Center — 9767 NC 210, Angier, NC
Bioretention Cell Calculations
Drainage Area
Impervious -
Open Space =
Total -
Rv = 0.05 + [0.9 x 46% impervious]
Rv = 0.46
V = 3630 x l(in) x (0.46) x (1.82) = 3,039 C.F.
Volume Required (cfl
Volume Provided (cfl
S.A. Required - C.F. / 1.0'
S.A. Provided
- 0.84 acres (46%)
- 1.04 acres (54%)
- 1.52 acres (100.0%)
3,039 C.F.
3,094 C.F.
3,039 S.F.
3,094 S.F.
(SEE SHEET C3.0 FOR GRADING PLAN & C 7.1 FOR CONSTRUCTION DETAILS.)