20080684 Ver 2_Stormwater Info_20080619

0
D
colejt
& stone
Land Planning
L andscca c Architecture
GO ?1'tiJ +'tt!"r'1ltt?
Urban D'?rq;;.
200 South Tryon Street
Suite 1400
Charlotte, North Carolina 28202
Tel 704. 376 t 5 5 5
Fax 704. 376, 7851
www.colP jeneststonexom
_U8LO 4 vim.
Northlake Business Park
CJS # 3716
CALCULATIONS FOR:
Storm Drainage
Detention
Erosion Control
Water Quality
DATE: 09/07/07
REV.
05/13/08

p
_ SEA
?^ ?.•y l..t CY ``y...
if?+1,+,u irI++0
TABLE OF CONTENTS
DESCRIPTION
PROJECT SUMMARY
STORM DRAINAGE
EROSION CONTROL
WATER QUALITY
ATTACHMENTS
SECTION
1
2
3
4
5
Northlake Business Park La P6MU*
?:
'°
PROJECT NO.: 3716 BY: CB .
7.tilf's "W"? CWFJVAWftW
DATE: 91712007 T.M.: DBS ufmasbc
REVISED: 511312008 P.M.: DDS PROJECT SUMMARY
INTRODUCTION:
The Northlake Business Park is commercial development located at the north-east corner of US 21 (Statesville Rd.)
and Alexanderana Rd., in the Town of Huntersville, North Carolina. The site is connected to the Long Dixon Creek by
two (2) un-named creeks. The project is set on a 16.6 Acres lot which will be developped in two (2) Phases. The first
Phase of the development will consist of the construction of the 40,000sf Medical Office Building and all it's
appurtenances, including, raingardens and detention ponds as well as the proposed public road (Hunstad Blvd.). A
small protion of Phase 2, located to the south of Hunstad Blvd., must be graded to balance the earthwork of Phase 1.
The grading of phase 2 has been minimised to have a temporay tree save along US 21 for public perception. All
erosion control measures will be placed to protect this minimal grading of Phase 2. The final Phase 2 of the project
will be built out at a later date. The Phase 2 development will consists of four (4) buildings totalling 96,000 sf of
various retail, office and restaurant space.
Rain gardens and detention ponds associated with Phase 2 of this project will not be built during the first phase of
the project. The rain gardens and detention ponds are designed to mitigate the increase run-off from the project and
minimize the impact of this development on downstream areas and meet the water quality requirements of theTown
of Huntersville.
Northlake Business Park LadPfom6if °, ??°°-?
PROJECT NO.: 3716 BY: CB # ,?'...
n
DATE: T.M.: DBS _
ta*M oo*
REVISED: 511412008 P.M.: DDS DETENTION CALCULATION SUMMARY
DRAINAGE AREA Al
Tributary area: 1.315 Ac
Peak
Control
Volume
Control
Tcpre = 17.1 min
Tcpost = 5.0 min
1 yl
2 yi
10 yr
50 yi
CNpre = 70.0
CNpost = 94.0

Qpre (CfS) Undetained
Qp0st (CfS) Detained
Qpost (CfS)
We?ev (ft)
0.61 3.44 0.02 801.27
1.07 4.31 0.06 801.30
2.79 6.97 2.16 801.44
4.77 11.87 11.87 801.77
1 yr - 24 hr
1 yr:
Hyg - Vol pre Hyg - Vol post
0.054 Ac-ft 0.189 Ac-ft Vol. Control: 0.189 - 0.054 = 0.135 Ac-ft

Rain Garden A2: Volume above mulch
= 1,503 sf x 12" = 1,503 cf
= 0.035 Ac-ft
Volume control in detention pond A2: 0.135 - 0.035 = 0.10 Ac-ft
Orifice for 2 day drawdown: 0.73" dia (0.06 ft)
Weiev 1 yr volume control = 801.29
Northlake Business Park cm rpwm* .?
ndw 14M
PROJECT NO.: 3716 BY: CB # > rs.A.. , c--s-
xtos rn
OWFJ
*NA

DATE:
T.M.: DBS S
? .r T"t
U4= DS*
REVISED: 511412008 P.M.: DDS DETENTION CALCULATION SUMMARY
DRAINAGE AREA A2
Tributary area: 1.479 Ac
Peak
Control
Volume
Control
Tcpfe = 13.56 min
Tcpost = 5.0 min
1 yl
2 yi
10 yr
50 yi
CNpfe = 70.0
CNpaSt = 94.0

Qpre (CfS) Undetained
Qpost (CfS) Detained
Qpost (CfS)
Welev (ft)
0.76 4.01 0.03 799.01
1.29 5.02 0.06 799.22
3.32 8.13 2.93 799.37
5.75 11.19 14.39 799.67
1 yr - 24 hr
1 yr:
Hyg - Vol pre Hyg - Vol post
0.061 Ac-ft 0.220 Ac-ft
Vol. Control: 0.220 - 0.061 = 0.161 Ac-ft
Rain Garden A2: Volume above mulch
=2,103sfx 12"=2,103cf
= 0.048 Ac-ft
Volume control in detention pond A2: 0.161 - 0.048 = 0.112 Ac-ft
Orifice for 2 day drawdown: 0.80" dia (0.07 ft)
We,ev 1 yr volume control = 799.22
Storm Drainage
Analysis

C9 Vi

' m v m r M o N m
V7
C N
I
I
I
tl O C N, coi, m r- M (D OI , f`
m
i?
'-p
y, "T
m co
a ?
O o
m M
O, M
0 O
c) ui
O v1 c-i
O,O Qj
m
l
C ? N W r c0 eD [O dD w i m r-
_
T J I i
= i

a0 aD M N M N N CF) V O O
V ?I Lo oD N N M m 0 m CO CD

d,
A C V
m
r" m
o
oo 00
o
co N
o
co M
o
oo CO
o
co O
o
oo (n
o
co V
ol
co Mom
O;m
c0
? J
T
2
E
'
m r o o OI O M o oI o O o o
oI o M C) C) r- oi o c o 0 0
H O
m: V
a) N m j
C) O

c' (O
O 7
O
c: 01
OH
) 1-
O (o
O Lo
O m
m
>I
C
2 ? ? ?? c' ? I

oo

co C)
-
O W l I I
N
C C
O> O O
o O
co O
O O
o M
r` M
r- O
o 0
o 0
V 0
o 0
0
cD N N m (D (D V r-- r M m
tll (0
O. > 0
oo
ao
oo 0
a0 0
oD 0
o0 0
a0 0
00 0
M 0
00 0
oD
N
W
E
_
R
d C
O O_

(n
O

m
m

c
(P

(n
f?

O
m

m
?

M
V

N
?

m
?

m
M ?

0
O
N>
A V r M M N m d' M N m
C
? m
r O
m O
m m
r O
co O
m m
? 0
co 0
ao 0
imi m
r?
p W
(E6 O co LO o Ix) o o oD u) ' I
` O
> Cl
V m
N r
r- r- N
M W
N V
m N
V
V m
N r
m
N C N
a- >I m
I- o
cc) 0
co 0
co 0
co 0
co m
r- o
co o
co O
co m
D dl
Wj

' I
l
r
Ln
(n
N
M
co
(D
m
r-
r--
a y 10 B 7 C m V (O LO N
U v V O O cl
cl) r- r- (() V V 'q V
L
LL
d
N
4,
L
0
C
L
0
C
L
0
C
L
U
C
L
U
C
L
U
C
L
U
C
L
U
C
L
U
C
L
U
C
L
U
C
Q _ _
W _
m _
w _
m _
w _
V ((] _
(I7 _
(P m
N

d

N
i
;O

O

O I

'u]

U)

N

LO

(n

L

v
a i
O o
O l?
i0
0 6 1Z
0 0
0 0
o 0
Io 6
0 0
0, 0
0
(n-- O O O O O 0 0 0 0 0
I 0
w
C w
LL? ?
m!
(DI
O
m
co

m I
v
l
m
? Lo N m M N N N (D M (N
O
(D ,
E w
m a
V
oo
A l
'
in
L
r
)
c0
M
m
r-
R
N
O Vl ; (n
O Ln L
'
' m
N m
N R
N ((A
M to
Mi m
M
F O ?
LL
E
m
m y
N 01 ('7 M N M N V M N r
O
O Zi
p
Q
Q
Q
Q
Q 'T (ryy
Q
c?
Q
Q ry
Q
(n
0 W
LL CO
U CO
(n c
? CO
1 U m
CO W
LL m
U I
CO
W CO
? W
LL
R A N (n V I M V M (N 10 V I M N
Z QI Q QI iQ Q Q Q Qj Q
Q
a
? m U U m U U m 'U U i
w C°
(
n U
i i
B

OFF-SITE DA
.1
r . r ¦
' a

.¦rrw r
?wrri
Out A
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

--?r -y
y r,
H T' r .M
A- Le'

8x4 BOX CULV 10yr STRM 12"RIPRAP BOT
Worksheet for Rectangular Channel
Project Description
Project File plsdskproji37161engineeringlflowmasterlcrossing.fm2
Worksheet 8x4 box culvert- buried 12inch
Flow Element Rectangular Channel
Method Manning's Formula
Solve For Channel Deoth
Input Data
Mannings Coefficient 0.045
Channel Slope 0,011600 ft/ft
Bottom Width 8 00 ft
Discharge 105.56 cfs
Results
Depth 2.70 ft
Flow Area 21.59 ft2
Wetted Perimeter 13.40 ft
Top Width 8,00 ft
Critical Depth 1,76 ft
Critical Slope 0.039735 ft/ft
Velocity 4.89 ft/s
Velocity Head 0.37 ft
Specific Energy 3.07 ft
Froude Number 0.52
Flow is subcritical.
t? 5i1=4r0RowNlaster v513
10 50 05 AM Haestad :MeW..OdS !nc 3- 3r;oKiide goad Waterbury CT 06'708 L203j 755-1663663 Wage 1 of 1
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
TM 5-820.4/AFM 88.5, Chap 4
12
600
500
EXAMPLE
0
'
'
400 80c 0 = 75 css
5
.2
Va - 50s±+.
9 300 , sr "w Kw
D fee,
1 75 ) 5
- 20C} :.21 'go
3.8
S) 2,05 4 t
r
6
5
r
w
Z 4
a
K
r?
m
s
c?
w
2
d
700
O
00 n0 2
a
39
-
- 2
s, t Z
60

O
50
d
-44
? 40
Z
30

R
5y

?, 20 .
?p0 ).0
-' - d 2_ _..._
. _
?r 4 t.C

N M!ngxoil d
4 i0 C1ort -? UJJ 9 .9

Z

N w
F -.8
o
a .._ 7
6 3:
d O
O 5 HW WINGWALL w .7
SCALE
.
4 0 FLARE _ 6
a
? c':1 30- eo ts'

(3) J-(atansiuns 5
2 Of $,is$)
.5
To oss sco4 (2) or (3, Project
nnr,sontauT to idols (t), tnfn
os? snogh.ne?n?a ',ns rhrougn 4
u Ind Q scoffs,*, 'twit 3%
,?iusteott7.
2
bW
).S
(.0
9
7
5
- 8 4 4

35 L
35
5 .30 .

X A/ box et44 VIM T
tkj IF D 'RIP RA r
B-8 A4DA/e, 507'7"pM
(1) (2) (3)
8 - 9 - 10
- 8
7
7 El
6
7
6
5 6
5
4 5
4
4
3
3
3
s• ?
U 3•o Fket i`.GOW?
4,?,=1 Sa. a t arr
his' I ? y. 9de s,?
716 orthtake P _
tediment IPRAP APRON SIZING
3716 BY: CS ased on Army Corps of Engineers Reports H-70-2
DATE: 02/28/08 T.M.: DBS -72-5. and NJ Standards for Soil Erosion and
REVISED: 05113108 P.M.: DDS C ontrol(199%
Structure Road Crossino Culvert
Calculation for dual 8x4 box culvert w/ 12" burial at Ditch crossing
Iftnut -1
Effective Culvert Hight, Ho 36 Inches or 3 Feet
Peak Flow, Qio * 1066 CFS (Use 10-Year Discharge, See Pond Pack Calculation)
Tailwater depth, Tw 0.6 Feet ( If Unknown, use 0.2 x Diameter in Feet)

*Q10 = 105.56/2 = 52.78
2gWgn:
Apron Length, La = Feet Long
IF TW<Hc?2, La=(1.8q((Do".5))+7Do IF'fWiHd2, La=(3g1(Do^.5))
Apron Width, Wa = Feet Wide (Only if no well-defined channel downstream )
ff TIN <Ho/2, We = 3Ho + La N TW > Ho12,Wa = 3Ho+ 0.4La
dso Stone Size = dso in Feet
dso in Inches CLASS 2 dso = 0.016/TW x (q)
A ron Thickness= Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECW"TI ONS
RIP RAP M144MUM MIDRANGE MAOXIML A
CLASS lit
A 2 4 6
B S a t1
1 S 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
4) See NCDOT detail 876.02 Sheet 1 of 1 "GUIDE FOR RIP RAP AT PIPE OUTLETS" for sizing of the Riprap Apron.
Data calculated above is to determine the riprap class only. This method was proposed and approved with Mike Maclntyre,
Mecklenburg County-Land Use and Environmental Services Agency per email May 7th, 2008. Apron Thickness is to be a
minimum of 12", see CJS plan CV4.3 for location of filter fabric.
01
`HJI3 tbS
SAVMHOIH 30 NOISIAI7
NOI1VltiOdsNVR1 JD Nld3a S131inO 3dld IV deli dItJ SOd aain!O -°?
VPbI7GSVO H1IlON €
JO 3lViS 41? 80d ONIMVHG (18VaNVIS HSI]ON3 x'00
L,J
k
4
00
t

N ?

N co
co
'C
`r
-
N
? e

i
US `?` 0
.
O!
,s
Q.. 4
. h c0
M M 0 T
CC _.
?. z N: C} h tfi ZD M 'J O7 h i
'..
N it

fn
c( in m
W I's
X, > t(7 fif ;n O M h
w K1 U! r CV N M cD
h
CD
O p in
>
.
w 000
Lu
d? •r p V car
r z4n
O z d
<

m <
CL
-
? a cm m 0 ai M
y°" 3
O=
L 1 - W
Lu (4)
CS 3 2
C cr w
€wx
Q. ? x r o
Z!. ?ww
F° z D
1- ILJ Q x
U< J H .d
W F' a.Q<
LL M<
O °a°;
a.,aG
oa
n fn
?. yr m
STATE OF " -"`
NORTH CAROLINA
DEPT. OF TRANSPORTATION
DIVISION OF HIGHWAYS
RALEIGH, N.C.
......_...
_...........
<
rxwv
° ua N
z s- r--

ENGLISH STANDARD DRAWING FOR ^!,N
GUIDE FOR RIP RAP AT PIPE OUTLETS`
U?
J?
co
Q
N ?
rr
ig m
v Q
?uL€ 1-i
1L f
uj;
W
"
b.
N
:J'
d?? ?. ???i, € I ICI
I!I
sl
?II',?I!I'?
?', "' F If
.????
'' ?''? I
?', ? ?
'a ,I
?? ??i'?I I ??;
p
?I ? ' ??
i??G
I?'?'
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Detention
Analysis
RG Al & DET Al
Addlink 10
DA-A1-Pre Junc 10
DA-RGA1-Fast Ad atin 20 RGA1
Det Pond Al
Route aut RGA 1
Detention area
Out 10

r I
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

• n k a k•. k k a. A k k' k: tr. ?"?. _J. ._ M' k k i v ?. a a' A a .<< .' Y A

k x a>< n v, z a} k rt tr.- v*a f'y ... ,.v .;; A t k a ... «.<. a k.

.., M ., _
F? ??.: -? ... -.,-
_ ... _ ,
.,
S
•
•
•
•
•
•
•
•
•

_ .. 1 : _._ _W.... T.e : ,.

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

;� - - -
_ v; .. _
_.. . _ . .. .. _ _ � _.._ _��ti . ,_ �,----�, _ -�_ ..._ .. � __... .__

n
,
- - - - - - - - - - - - -
aar

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

? ., ,
_.. ???r: -?? --_____

? ._.
F.��. ... �. .. .,.. .._ _ ...<. ,. �� _...

•
•
•
•
•
•
•
---------- ----- ----- ------

ea

- - - - - - - - - - - - - - - - - - - - - - - - - - -

.. ,1..,... ..'1 _ _? __.G_?C? .. ....,__...__ ..?.?.P....?..

'-n n'. _.

R"3a2_

r,
f .3
FT, ^' ? t..:d,
--------------
,r..
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
- - ... 7 I _ .. .. A.".
. -- !: `NAP :I a ._? _

Northiake Business Park r etr.rM ?^-?
PROJECT NO 3716 BY CB ,
DATE: 09107107 T.M.: DBS "'..fAQflil oq¦
REVISED: 05113108 P. M.: DDS 1-Year 24 Hour Drawdown - Drv Detention Basin Al
Volume Control -- 1-Year 24hr storm 2-5 Day Drawdown
Bottom of Pond Elevation 797.99
Bottom of Pond Area 0.00 Ac
1-Year 24hr storm 2-5 Dav Drawdown Volume
Volume to be released
Vol-1yr pre = 0.054 ac-ft' ' See Pond Pak detention talcs
Vol-tyr post = 0.189 ac-ft' ' See PondPak detention talcs
Vol to be controlled: 0.135 ac-ft
Storage in RGA1 Bott. Area X 12"=
1503X1ft = 1503 cf
= 0.035 ac-ft
Vol.Stor in Det pond= 0.100 ac-ft
This volume must be released over a period of 2-5 days 0.10 ac-ft
or 4378 ftA3
As designed pond areas.
Storage Volumes
Cumulative
Elevation Area(ac) Volume(ac-ft)
797.99 0.0000 0.00
798 0.0156 0 00
799 0.0242 0.02
800 0.0334 0.05
801 0.0433 0.09
802 0.0537 0.13
803 0.0647 019

Interpolation to find elevation at which required storage volume is reached
Storage Storage
Elev volume area
801 0.09 0.04
Elev 0.10 0.03
802 013 0.00
Elev= 801.29
Storage elevation = 3.30 feet above bottom of pond elevation
Determination of Orifice size for 2-5 day drawdown
a= 2A x sgrt(h) 'Falling head equation
Ct(sgrt(2g))
a= Area of orifice a soft
t= Time to drawdown 172800 sec Assume 2 day minimum
A= Average pond surface area 670 sf
g= Gravity constant 32.2 fUs12
h= Change in head 3.30 ft
C= Orifice constant 0.6
Maximum orifice area = 0.002926618 sgft
Maximum orifice Diameter= 0.73 inches (2 day drawdown)
0.06 feet

ws._
---------------------
. _ ,_ � _.. a �.a. �a.. _�
. ,. ,...� r.._� — ,._---�__�._.� _._

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

- - - - ---- - - - - - - - - - - - - - - - - - - - - - - - - - -

-_ _ ? ? ;:

�_ ,�_ t — e. .._
,.. __. .. _,. 1 .. ....
_ ,. . _._ ��� — ,. 1, .. .—.. _..

-----._ t _ ._ _...
o ? ?. ? .!_1 ... _ . y
Northlake Business Park ? " ?'"`?"` I 4M
PROJECT NO. 3716 BY: CB ` caTA 704. rr& wight S"
DATE: 09/07/07 T.M.: DBS U 0#M ow r
REVISED: 05113108 P.M.: DDS FLOATATION CALCULATIONS
For OS-A1
CONSTRAINTS:
Weight of Concrete
Weight of Water
Safety Factor (S.F.)
Height of structure
Structure thickness
Outlet box width
150 lbs/ft^3
62.4 Ibs/ft"4
1.25
3.91 ft
6 in
4ft
Weight of outlet structurefWs)
Ws = (width + thickness x 4) x thickness x height x weight of concrete =
Weight of water displaced
Ww = (width + 2 x thickness x 4) x Weight of water x height = 4879.68 Ibs
Size Base
Wb=(S.F.xWw)-Ws= 821 Ibs
Footing size
Required concrete = Wb / Weight of concrete = 5 cult
*Assume base is 6" wider than exterior box width and minimum thickness is 8".
Thickness of base = 0.67 ft
5279 Ibs
Length = 6.00 ft
Width = 6.00 ft
Thickness = 0.67 ft
Dss Park
371s BY: CB
09/07/07 T. M.: DB:
Structure HW-A1-1
!AP APRON SIZING
on Army Corps of Engineers Reports H-70-2
, and N.J. Standards for Soil Erosion and

Pipe Diameter, Do 36 Inches or 3 Feet
Peak Flow, Qio Z16 CFS (Use 10-Year Discharge
Tailwater depth, Tw 0.6 Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 1.68 ftts (From StormCAD - 0 ft/s assumed for Level Spreader Overflow)

Apron Length, La = 21.7 Feet Long
IF 7W<Da2, La=(1.8q1(Do".5))+7Do IF 1W>Da/2, La=(3g1(Do".5))
Apron Width, Wa = 30.7 Feet Wide (Only if no well-defined channel downstream)
If TIN <Do/2, Wa = 3Do + La If TIN > Do/2, Wa = 3Do+ 0.4La
d5o Stone Size = 0.02 dso in Feet
R d5o in Inches CLASS A dso = 0.016/TW x (q)',33
,Apron Thickness= o Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP WNIMUM MIDRANGE MAXIMUM
CLASS N. IN. IN.
A 2 4 S
B 5 8 11
1 5 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
•
3716 - HW Al - DET. POND Al OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet HW Al - DET. POND Al OUTFLOW PIPE 10YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 2.16 cfs
Results
Depth 0.74 ft
Flow Area 1.36 ft2
Wetted Perimeter 3.12 ft
Top Width 2.59 ft
Critical Depth 0.46 ft
Percent Full 24.70
Critical Slope 0.014275 ft/ft
Velocity 1.59 fus
Velocity Head 0.04 ft
Specific Energy 0.78 ft
Froude Number 0.39
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.000036 ft/ft
Flow is subcritical.
05/14/08 FlowMaster v5.13
09:44:14 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
3716 - HW Al - DIET. POND Al OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet HW Al - DET. POND Al OUTFLOW PIPE 25YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 5.99 cfs
Results
Depth 1.26 ft
Flow Area 2.83 ftZ
Wetted Perimeter 4.24 ft
Top Width 2.96 ft
Critical Depth 0.77 ft
Percent Full 42.16
Critical Slope 0.0133 25 ft/ft
Velocity 2.12 ft/s
Velocity Head 0.07 ft
Specific Energy 1.33 ft
Froude Number 0.38
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.0002 75 ft/ft
Flow is subcritical.
05/14/08 FlowMaster v5 13
09'45:19 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
i
•
•
3716 - HW Al - DET. POND Al OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet HW Al - DET. POND Al OUTFLOW PIPE 50YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 11.87 cfs
Results
Depth 1.91 ft
Flow Area 4.75 ft2
Wetted Perimeter 5.55 ft
Top Width 2.89 ft
Critical Depth 1.09 ft
Percent Full 63.70
Critical Slope 0.0134 09 ft/ft
Velocity 2.50 ft/s
Velocity Head 0.10 ft
Specific Energy 2.01 ft
Froude Number 0.34
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.001080 ft/ft
Flow is subcritical.
05/14/08 FlowMaster v5.13
09:46:20 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
111 I 1.. , ,l lmnlqPlIl7
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
i
•
r
r
•
•
•
i
•
•
M
•
i

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Detention
Analysis
RG A2 & DIET A2
ti
Addlink 10
DA-A2-Pre Junc 10
DA-RGA2-Post A001in RG A2 Det Pbnd A2
2(1
W W Routemout RGA2

Detention Area
? e °rltb ,.,,.
Out 10
__.. «.. ... .. .. .._ .... .��li� .., _.w __� _?_..

......?
-PPIE,
»v.....,. M . ............... 1.....
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
.... ??_ .............?._.. 4
... ,., ????: _ ??r ?k__ ................... ..__
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

4 ? __

,_;
__
.._ - .,
,.
?,_ _ ?:
r- _ _ _ .,

?; ? :?
_.
. , _ _.
_,

. ?•: ':
1.
,?
1_... .__ .___ .___

x

---------- -----------

.. .. .. ... .... ... .. . . .. . ... ... -------------------
42,

- _ ... r ?_ ? _ ,.. .. .??t ,
M .. _ _ ._

- - - - - - - - -- - - - - - - - - -

_.. -.... i _ _..
,..
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

.. ..
r }' _" .. _. Y?''..

"17 1 _,... _. ,f;
s
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
,_ 7 _.? ?.
_. ?? ?t ?, ? ? G

- - - - - - - - - - - - - - - - - . .... ... ... ... .

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
?m. - , .?, ?
v
.-F? ? ?.?-

3n
-------------- .... . . ... .... ... ...
,. �a � .. .:... .
. _ . � �'-
_. ... , T .. ..._ ..
.. :: satin_ i. .,!.
-' `� ._. ., ....__ _._____•

.. _.
-- ----------

--- -------------------
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Northiake Business Park t.ee.y =71-
PROJECT NO 3718 BY: CB OO
W
S m
DATE. 09107107 T M.. DBS W
tTi?g1M ...rr.+.....
REVISED. 05113108 P. M.: DDS 1-Year 24 Hour Drawdown - D Detention Basin A2
Volume control
Volume Control -- 1-Year 24hr storm 2-5 Day Drawdown
Bottom of Pond Elevation 795.99
Bottom of Pond Area 0.00 Ac
1-Year 24hr storm 2-5 Da y Drawdown Volume
Volume to be released Vol-1 yr pre = 0.061 ac-ft' ' See Pond Pak detention talcs
Vol-1yr post = 0221 ac-ft' ' See Pond Pak detention talcs
Vol to be controlled. 0.160 ac-ft
( Storage in RGA1 Bott. area X 12"=
2103X1 ft = 2103 cf
= 0 048 ac-ft
Vol.Stor. in Det pond= 0.112 ac-ft
This volume must be released over a period of 2-5 days 0.11 ac-ft
or 4867 ft^3
As designed pond areas:
Storage Volumes
Cumulative
Elevation Area(ac) Volume(ac-ft)
795.99 0.0000 0 00
796 0.0206 0 00
797 0.0289 0.02
798 0.0378 0.06
799 0.0472 0.10
800 0.0573 0.15
801 0.0677 0.21
Interpolation to find elevation at which required storage volume is reached
Storage Storage
Elev volume area
799 0.10 0.05
Elev 011 0.04
800 0.15 0.00
Elev= 79922
Storage elevation = 3.23 feet above bottom of pond elevation
Determination of Orifice size for 2-5 day drawdown
a= 2A x sgrt(h) 'Falling head equation
Ct(sgrt(2g))
a= Area of orifice a soft
t= Time to drawdown 172800 sec Assume 2 day minimum
A= Average pond surface area 803 sf
g= Gravity constant 321 ft/s^2
h= Change in head 3.23 ft
C= Orifice constant 0.6
Maximum orifice area = 0.003469558 soft
Maximum orifice Diameter= 0.80 inches (2 day drawdown)
0.07 feet

.. - . _ r?t .. .
..,. - ? t r

...__ x".,. :';
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
?°, _ °a
_ _ts
. ..?
.. .,.., ___. ,
_.?.. _. _.

:„1
:.'' ... .
. .. _ .. -?
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
F
L, S
--------------------

_.._ .. - z _ : _ � _.._

------- -----

... 1. -:.
., ? it_??a ... . , ._
•
•
IOW P(te) ?. , "'" W
Northlake Business Park
-6- IS202
at x.176_ C
AMMAtm PROJECT NO. 3716 BY: CB l 1 1 ? MWO 555
DATE: 09/07/07 T.M.: DBS uOs D,4p
REVISED: 05113108 P.M.: DDS FLOATATION CALCULATIONS
For OS-A2
CONSTRAINTS:
Weight of Concrete
Weight of Water
Safety Factor (S.F.)
Height of structure
Structure thickness
Outlet box width
150 Ibs/ft^3
62.4 Ibs/ft^4
1.25
3.91 ft
6 in
4ft
Weight of outlet structure(Ws)
Ws = (width + thickness x 4) x thickness x height x weight of concrete =
Weight of water displaced
Ww = (width + 2 x thickness x 4) x Weight of water x height = 4879.68 Ibs
Size Base
Wb=(S.F.xWw)-Ws= 821 Ibs
Footing size
Required concrete = Wb / Weight of concrete = 5 cult
"Assume base is 6" wider than exterior box width and minimum thickness is 8".
Thickness of base = 0.67 ft
Length = 6.00 ft
Width = 6.00 ft
Thickness = 0.67 ft
5279 Ibs
Northiake Business Park RIPRAP APRON SIZING
PROJECT NO. 37161 BY: CB ased on Army Corps of Engineers Reports H-70-2
DATE: 09/07/07 T.M.: DBS -72-5, and N.J. Standards for Soil Erosion and
REVISED: 05113/08 P.M.: DDS Control (19%)
Structure FES-A2-2

Pipe Diameter, Do 36 Inches or 3 Feet
Peak Flow, Clio 2.93 CFS (Use 10-Year Discharge
Tailwater depth, Tw 0.6 Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 1.76 ft/s (From StormCAD - 0 ft/s assumed for Level Spreader Overflow)
i
Apron Length, La = 22.0 Feet Long
IF 7W<Do/2, La:,-(1.8q/(Do^.5))+7Do IF 7W>Dd2, La=(3cy(Do".5))
Apron Width, Wa = 31.0 Feet Wide (Only if no well-defined channel downstream)
If TW <Dod2, Wa = 3Do + La If TW > Da?2; Wa = 3Do+ 0.4La
dso Stone Size = 0.03 dso in Feet
6.3 dso in Inches CLASS A dso = 0.01617W x (q)' .33
Apron Thickness= 10 Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP MINIMUM MIDRANGE MAXIMUM
CLASS N. IN. N.
A 2 4 6
B 5 a 11
1 5 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
•
•
3716 - FES A2-2 - DIET. POND A2 OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet FES A2 - DIET. POND A2 OUTFLOW PIPE 10YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 2.93 cfs
Results
Depth 0.87 ft
Flow Area 1.69 ftz
Wetted Perimeter 3.40 ft
Top Width 2.72 ft
Critical Depth 0.53 ft
Percent Full 28.84
Critical Slope 0.013894 ft/ft
Velocity 1.74 ft/s
Velocity Head 0.05 ft
Specific Energy 0.91 ft
Froude Number 0.39
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.000066 ft/ft
Flow is subcritical.
05/14/08 FlowMaster v5.13
09:49:53 AM Haestad Methods, Inc 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
0
0
0
0
0
0
0
0
0
0
0
0
0
•
3716 - FES A2-2 - DET. POND A2 OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet FES A2 - DET. POND A2 OUTFLOW PIPE 25YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 7.36 cfs
Results
Depth 1.42 ft
Flow Area 3.30 ftZ
Wetted Perimeter 4.55 ft
Top Width 3.00 ft
Critical Depth 0.85 ft
Percent Full 47.36
Critical Slope 0.013269 ft/ft
Velocity 2.23 ft/s
Velocity Head 0.08 ft
Specific Energy 1.50 ft
Froude Number 0.38
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.000415 ft/ft
Flow is subcritical.
05/14/08
09:48:01 AM
FlowMaster v5.13
Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
•
•
3716 - FES A2-2 - DET. POND A2 OUTFLOW
Worksheet for Circular Channel
Project Description
Project File p:\sdskproj\3716\engineering\flowmaster\3716-fes.fm2
Worksheet FES A2 - DET. POND A2 OUTFLOW PIPE 50YR
Flow Element Circular Channel
Method Manning's Formula
Solve For Channel Depth
Input Data
Mannings Coefficient 0.024
Channel Slope 0.002000 ft/ft
Diameter 36.00 in
Discharge 14.39 cfs
Results
Depth 2.21 ft
Flow Area 5.57 ftZ
Wetted Perimeter 6.18 ft
Top Width 2.65 ft
Critical Depth 1.21 ft
Percent Full 73.53
Critical Slope 0.0136 12 ft/ft
Velocity 2.58 ft/s
Velocity Head 0.10 ft
Specific Energy 2.31 ft
Froude Number 0.31
Maximum Discharge 17.38 cfs
Full Flow Capacity 16.16 cfs
Full Flow Slope 0.001587 ft/ft
Flow is subcritical.
05/14/08 FlowMaster v5.13
09.52.58 AM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 [phone] Page 1 of 1
Northlake Business Park RIPRAP APRON SIZING
PROJECT NO. 3716 BY: CB Based on Army Corps of Engineers Reports H-70-2
DATE. 09107107 T.M.: DBS -72-5, and N.J. Standards for Soil Erosion and
REVISED 05113108 P.M.: DDS Sediment Control (1999)
Structure FES-A2-1

Pipe Diameter, Do 15 Inches or 1.25 Feet
Peak Flow, Q1o 152 CFS (Use 10-Year Discharge
Tailwater depth, Tw .2$ Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 3.74 ftis (From StormCAD - 0 ft/s assumed for Level Spreader Overflow)

Apron Length, La = 13.3 Feet Long
IF TW<Do12, La=(1.8g1(Do".5))+7Do IF T1,11 , La=(3q/(Do".5))
Apron Width, Wa = 17.0 Feet Wide (Only if no well-defined channel downstream )
If TW <Do/2, Wa = 3Do + La If TW > Do12,Wa = 3Do+ 0.4La
d5o Stone Size = 0.25 dsoin Feet
3.1 d5o in Inches B d50 = 0.016/TW x (q)'- "
Apron Thickness= 10 Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP MINIMUM MIDRANGE MAXIMUM
CLASS IN. IN. N.
A 2 4 6
B 5 8 11
1 5 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs lower foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
Northlake Business Park RIPRAP APRON SIZING
PROJECT NO.: 3716 BY: CB Based on Army Corps of Engineers Reports H-70-2
DATE: 09107/07 T.M.: DB$ -72-5, and N.J. Standards for Soil Erosion and
REVISED: 05113108 P.M.: DDS Sediment Controi (1999) 4? 1
Structure FES-A3-1

Pipe Diameter, Do 15 Inches or 1.25 Feet
Peak Flow, Qio 1.54
] CFS (Use 10-Year Discharge- StormCAD)
Tailwater depth, Tw 0.25 Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 1,45 ftls * (From StormCAD - 0 fUs assumed for Level Spreader Overflow)
* From Flowmaster
Design,
Apron Length, La = 10.7 Feet Long
IF TW<Do12, La=(1.8q((Do".5))+7Do IF IW>Dad2, La=(3g1(Do".5))
Apron Width, Wa = 14.5 Feet Wide (Only if no well-defined channel downstream )
ff TIN <Do?2, Wa = 3Do + La ff TW > Do12, Wa = 3Do+ 0.4La
dso Stone Size = 0.08 dso in Feet
1.0 dso in inches CLASS A dso = 0.016ITW x (q)""
Apron Thickness= 10 Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP MINIMUM MIDRANGE MAXIMUM
CLASS IN. IN. tAi
A 2 4 6
B 5 8 11
1 5 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
Northlake Business Park
RIPRAP APRON SIZING
_
PROJECT NO.: 3716 ~ BY: CB aced on Army Corps of Engineers Reports H-70-2
4
DATE: 09/07/07 T.M.: DBS -72-5, and N.J. Standards for Soft Erosion and
?
REVISED: 05/13/08 P.M.: DDS Control (1999)
Structure FES-A4-1

Pipe Diameter, Do 24 Inches or 2 Feet
Peak Flow, Q1o 2.81 CFS (Use 10-Year Discharge- StormCAD)
Tailwater depth, Tw 0.4 - Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 1.77 ftls (From StormCAD - 0 ftis assumed for Level Spreader Overflow)
I; n:
Apron Length, La = 15.9 Feet Long
IF TW<Da12, La=(1.8q/(Do^.5))+7Do IF TM-D&2, La=(3g1(Do^.5))
Apron Width, Wa = 21.9 Feet Wide (Only if no well-defined channel downstream)
N TW <Do/2, Wa = 3Do + La /f TW > Do/2, Wa = 3Do+ 0.4La
dso Stone Size = U.07 dso in Feet

1 0.8 dso in Inches GLASS A dso = 0.016r W x (q)1.33
Apron Thickness= 10 Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP MINIMUM MIDRANGE MAXIMUM
CLASS IN. IN. N.
A 2 4 6
B 5 8 11
1 5 10 15
2 4 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
i
•
•
•
Detention
Analysis
DET A3
FOR REFERENCE ONLY

Addllnk 10
DA-A3-Pre
Addlink 20
DAA3-Post Pond A3
Junc 10
A
Out 10
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
s
•
•
•
•
•
•
•
•
•
•
•
•

< z r.< e R r t ? x T rt e r z r ?f v x e t t k e K fi fi r r -< Y s

s
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
i
•
•
•
•
•
•
1f.1 ,. ..
-..
•
I �
3
1 _
. _t � . 5�:.:.
y
l
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

S
-----------------

..<._ Y { ... _� .. ....

i
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•

?_. ??? . ,_ .r=--
_� — x_.c ..�. �_

"?.f: -
... ?._
.. ,,. ?. :i? ?
., _ .i Y ., _ ? ?- - - - ... -.. ? ... ., _ t _, r _. ., s .. ., .,
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
=? _.
_ ..

a r�

.-, .. ,_

_. 1 __.�
..- _4:��� a,

.. _...
. ._ - .. '{

?. _
... .... ,
...,

?: - ..
., ? s
?.
.?? - ->?
?..

..._ -.
. - ..?:1 , _?? .. _ ?.
:.
Northlake Business Park lediment IPRAP APRON SIZING
PROJECT NO.: 3716 BY: CB ased on Army Corps of Engineers Reports H-70-2
DATE: 09/07107 T.M.: DBS -72-5, and N.J. Standards for Soil Erosion and
REVISED P.M.: DDS Control (1999) 1 4> 1
Structure FES-D-61
JER "' -1
Pipe Diameter, Do 36 Inches or 3- Feet
Peak Flow, Qio 9.51 CFS (Use 10-Year Discharge
Tailwater depth, Tw 04 Feet ( If Unknown, use 0.2 x Diameter in Feet)
Velocity, V 6.05 ft/s (From StormCAD - 0 ft/s assumed for Level Spreader Overflow)
RgWgn?
Apron Length, La = 24.3 Feet Long
IF TW<Dol2, La=(1.89((Do^.5))+7Do IF iW5,Do/2, La=(3g1(Do".5))
Apron Width, Wa = 33.3 Feet Wide (Only if no well-defined channel downstream )
ff TW <Do12, Wa = 3Do + La ff TW > Do?2, Wa = 3Do+ 0.4La
d5o Stone Size = 0.12 dso in Feet
1.5 dso in Inches CLASS A dso = 0.0161TW x (q) .33
Apron Thickness= 10 Minimum 10 inches
RIP RAP GRADATION PER NCDOT SPECIFICATIONS
RIP RAP MINIMUM MIDRANGE MAXIMUM
CLASS IN_ IN. IN.)
A 2 4 6
B 5 8 11
1 5 10 15
2 9 14 23
Notes:
1) q=Unit Discharge in cfs pwer foot of width.
2) filter fabric layer is to be used on all outlets.
3) riprap apron thickness designed to be 2 times the d50 when using filter fabric (3 times without).
10 I
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
i
Erosion Control
Analysis
SEDIMENT BASIN CALCULATIONS
Northlake Business Park
CJS PROJECT NO.: 3716 C S?t
DATE: 91712007 BY. CB
REVISED: 05113108 RVW: DDS Land Wat,msq t rrisra A,crooctwf, a C"o Fr, reannr = Uun3 ite i?:?
FAIRCLOTH SKIMMER TYPE BASIN DESIGN FOR SEDIMENT BASIN #A1 - STAGE 112
DRAINAGE AREAS/REQ'D STORAGE
Total drainage area TDA 1.2 ac
Disturbed area(DA) 1.2 ac
R d volume storage 1800xDA 2214 cf
BASIN CONFIGURATION
Proposed volume depth 2.5 ft
Depth of flow over spillway 0.5 ft
Bottom elevation of basin 798.75 msl
Water Storage elevation 801.25 msl
Spillway crest 801.75 msl
To of Berm 803.25 msl
SPILLWAY DESIGN
DESIGN FLOW Q=CIA
Composite soil coefficient 'C'= 0.6
Area W= 1.2 ac
10 yr. storm rainfall intensity, T= 7.03 in/hr
Computed flow from site, 'Q'= 5.0 cfs
SPILLWAY SIZE (L=Q/(C*h Al .5) )
given C= 3.0 and
Spillway length flow depth = h= 0.50
10 ft
SKIMMER DESIGN (Required): 1 Skimmer
Drawdown Time (hrs): 30.8
Skimmer Size: 1.5 in.
Orifice Dia. Size: 1.5 in.
FAIRCLOTH SKIMMER DESIGN TABLE
CF drained Drawdown Factor CF drained Drawdown Factor
1.5" Skimmer 1728 1 day 960 4" Skimmer 18267 1 day 1454
3456 2 days 1920 36534 2 days 2908
5184 3 days 2880 54803 3 days 4362
6912 4 days 3840 72000 4 days 5816
12096 7 days 6720 127869 7 days 10178
2" Skimmer 3283 1 day 1123 5" Skimmer 32832 1 day 1642
6566 2 days 2246 65664 2 days 3283
9849 3 days 3369 98496 3 days 4926
13132 4 days 4492 131328 4 days 6568
22982 7 days 7861 229824 7 days 11491
2.5" Skimmer 5500 1 day 1144 6" Skimmer 51840 1 day 1814
11000 2 days 2304 103680 2 days 3628
16500 3 days 3432 155520 3 days 5442
22000 4 days 4576 307360 4 days 7256
38500 7 days 8064 362880 7 days 12701
3" Skimmer 9744 1 day 1382 8" Skimmer 97978 1 day 1987
19547 2 days 2765 195956 2 days 3974
29322 3 days 4146 293934 3 days 5961
39096 4 days 5528 391912 4 days 7948
68415 7 days 9677 658846 7 days 13909
ESTIMATED BASIN SIZE RECTANGULAR
Length(ft) Width(ft)
Bottom 38 17
To 56 35
PLANNED BASIN SIZE (REFER TO EROSION CONTROL PLAN
Elev. Area SF Cumulative Volume CF
798.75 956 0
799.00 1052 251
800.00 1455 1505
801.00 1884 3174
801.25 1995 3659
801.50 2108 4172
802.00 2338 5283
X X #VALUE!
X X #VALUE!
X X #VALUE!
BASIN EFFICIENCY
Volume required: 2214 cf
Volume provided: 3659 OKAY
Surface area required: 1625 sf
Surface area provided. 2108 OKAY
SKIMMER DESIGN Provided : 1 Skimmer
Draw down Time (hrs): 50.8
Skimmer Size: 1.5 in.
Orifice Dia. Size: 1.5 in.
This table contains
maximum drainage
volumes for a given
Skimmer size and
drawdown period.
The orifice area is
calculated by dividing
the Provided storage
volume by the
corresponding Factor.
The factors are taken
from the table and
were generated
assuming a constant
head.
The diameter of the
orifice is calculated by:
(2*(J(Area/3.14))
SEDIMENT BASIN CALCULATIONS
Northlake Business Park
CJS PROJECT NO.: 3716 CoWetwst
DATE: 9/7/2007 BY: CB
REVISED: 05113108 RVW: DDS Land P3°rw +I mT(vwt * '. ,.
FAIRCLOTH SKIMMER TYPE BASIN DESIGN FOR SEDIMENT BASIN #A2 - STAGE 112
DRAINAGEAREAS/REQ'D STORAGE
Total drainage area TDA 1.2 ac
Disturbed area(DA) 1.2 ac
R d volume storage 1800zDA 2214 cf
BASIN CONFIGURATION
Proposed volume depth 2.5 ft
Depth of flow over spillway 0.5 ft
Bottom elevation of basin 797.00 msl
Water Storage elevation 799.50 msl
Spillway crest 800.00 msl
To of Berm 801.50 msl
SPILLWAY DESIGN
DESIGN FLOW Q=CIA
Composite soil coefficient 'C' = 0.6
Area W= 1.2 ac
10 yr. storm rainfall intensity, 7'= 7.03 in/hr
Computed flow from site, 'Q'= 5.0 cfs
SPILLWAY SIZE L=Q/ C*h^1.5
given C= 3.0 and
Spillway length flow depth = h= 0.50
10 ft
SKIMMER DESIGN (Required): 1 Skimmer
Drawdown Time (hrs): 30.8
Skimmer Size: 1.5 in.
Orifice Dia. Size: 1.5 in.
ESTIMATED BASIN SIZE RECTANGULAR
Length(ft) Width(ft)
Bottom 38 17
To 56 35
PLANNED BASIN SIZE (REFER TO EROSION CONTROL PLAN
Elev. Area SF Cumulative Volume CF
797.00 1259 0
798.00 1646 1453
799.00 2058 3305
799.50 2273 4387
800.00 2494 5579
801.00 2947 8300
X X #VALUE!
X X #VALUE!
X X #VALUE!
X X #VALUE!
BASIN EFFICIENCY
Volume required: 2214 cf
Volume provided: 4387 OKAY
Surface area required: 1625 sf
Surface area provided: 2494 OKAY
SKIMMER DESIGN Provided : 1 Skimmer
Drawdown Time (hrs): 60.9
Skimmer Size: 1.5 in.
Orifice Dia. Size: 1.5 in.
FAIRCLOTH SKIMMER DESIGN TABLE
CF drained Drawdown Factor CF drained Drawdown Factor
1.5" Skimmer 1728 1 day 960 4" Skimmer 18267 1 day 1454
3456 2 days 1920 36534 2 days 2908
5184 3 days 2880 54803 3 days 4362
6912 4 days 3840 72000 4 days 5816
12096 7 days 6720 127869 7 days 10178
2" Skimmer 3283 1 day 1123 5" Skimmer 32832 1 day 1642
6566 2 days 2246 65664 2 days 3283
9849 3 days 3369 98496 3 days 4926
13132 4 days 4492 131328 4 days 6568
22982 7 days 7861 229824 7 days 11491
2.5" Skimmer 5500 1 day 1144 6" Skimmer 51840 1 day 1814
11000 2 days 2304 103680 2 days 3628
16500 3 days 3432 155520 3 days 5442
22000 4 days 4576 307360 4 days 7256
38500 7 days 8064 362880 7 days 12701
3" Skimmer 9744 1 day 1382 8" Skimmer 97978 1 day 1987
19547 2 days 2765 195956 2 days 3974
29322 3 days 4146 293934 3 days 5961
39096 4 days 5528 391912 4 days 7948
68415 7 days 9677 658846 7 days 13909
This table contains
maximum drainage
volumes for a given
Skimmer size and
drawdown period.
The orifice area is
calculated by dividing
the Provided storage
volume by the
corresponding Factor.
The factors are taken
from the table and
were generated
assuming a constant
head.
The diameter of the
orifice is calculated by:
(2*(-v(Area/3.14))
SEDIMENT BASIN CALCULATIONS
Northlake Business Park
CJs PROJECT NO.: 3716W?t
DATE: 91712007 BY: CB
REVISED: 05113108 RVW: DDS anco P`arnir ; » , ? ctm,?.7 +? e A
FAIRCLOTH SKIMMER TYPE BASIN DESIGN FOR SEDIMENT BASIN #A3 - STAGE 112
DRAINAGE AREAS/REWD STORAGE
Total draina a area TDA 4.5 ac
Disturbed area(DA) 3.0 ac
R d volume storage 1800xDA 5436 cf
BASIN CONFIGURATION
Proposed volume depth 2.5 It
Depth of flow over spillway 0.5 ft
Bottom elevation of basin 806.00 msl
Water Storage elevation 808.50 msl
Spillway crest 809.00 rnsl
To of Berm 810.50 ms/
SPILLWAY DESIGN
DESIGN FLOW Q=CIA
Composite soil coefficient 'C' = 0.6
Area 'A'= 4.5 ac
10 yr. storm rainfall intensity, T= 7.03 in/hr
Computed flow from site, 'Q'= 19.0 Cis
SPILLWAY SIZE L=Q/ C*h^1.5
given C= 3.0 and
S illwa length flow depth = h= 0.50
18 ft

SKIMMER DESIGN (Required): 1 Skimmer
Drawdown Time (hrs): 23.7
Skimmer Size: 2.5 in.
Orifice Dia. Size: 2.5 in.

ESTIMATED BASIN SIZE RECTANGULAR
Length(ft) Width^
Bottom 61 28
To 79 46
PLANNED BASIN SIZE (REFER TO EROSION CONTROL PLAN
Elev. Area SF Cumulative Volume CF
806.00 5968 0
807.00 6921 6445
808.00 7899 13855
808.50 8397 17929
809.00 8902 22253
810.00 9930 31669
X X #VALUE!
X X #VALUE!
X X #VALUE!
X X #VALUE!
BASIN EFFICIENCY
Volume required: 5436 cf
Volume provided: 17929 OKAY
Surface area required: 6175 sf
Surface area provided: 8902 OKAY
SKIMMER DESIGN Provided : 1 Skimmer
Drawdown Time (hrs): 78.2
Skimmer Size: 2.5 in.
Orifice Dia. Size: 2.5 in.
FAIRCLOTH SKIMMER DESIGN TABLE
CF drained Drawdown Factor CF drained Drawdown Factor
1.5" Skimmer 1728 1 day 960 4" Skimmer 18267 1 day 1454
3456 2 days 1920 36534 2 days 2908
5184 3 days 2880 54803 3 days 4362
6912 4 days 3840 72000 4 days 5816
12096 7 days 6720 127869 7 days 10178
2" Skimmer 3283 1 day 1123 5" Skimmer 32832 1 day 1642
6566 2 days 2246 65664 2 days 3283
9849 3 days 3369 98496 3 days 4926
13132 4 days 4492 131328 4 days 6568
22982 7 days 7861 229824 7 days 11491
2.5" Skimmer 5500 1 day 1144 6" Skimmer 51840 1 day 1814
11000 2 days 2304 103680 2 days 3628
16500 3 days 3432 155520 3 days 5442
22000 4 days 4576 307360 4 days 7256
38500 7 days 8064 362880 7 days 12701
3" Skimmer 9744 1 day 1382 8" Skimmer 97978 1 day 1987
19547 2 days 2765 195956 2 days 3974
29322 3 days 4146 293934 3 days 5961
39096 4 days 5528 391912 4 days 7948
68415 7 days 9677 658846 7 days 13909
This table contains
maximum drainage
volumes for a given
Skimmer size and
drawdown period.
The orifice area is
calculated by dividing
the Provided storage
volume by the
corresponding Factor.
The factors are taken
from the table and
were generated
assuming a constant
head.
The diameter of the
orifice is calculated by:
(2*(v(Area/3.14))
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
i
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Water Quality
Analysis
J
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
• O
low
• t!
• F
•
•
•
•
•
•
•
•
•
•
•
c
D
:a+
Q7
E
t/)
d?+
E
1°
i
/?Qry1
V
U
W

lw?
a

to _v 2
J 7• i. p

C o
b O
y

Q

L
O O N
d 0. Z y
? d
d

H

?1 0
'C. N?.o ID
C

? C

d

? d
' uj
v
Vi
0
C
0
0
O
C.
a
E
w
C
N
? a
co
a
E '
?.
O
V d
Y
O
N
N
a
'u
a
a
v
0

^ a?
in

r
a'

0
o

0
o
?

t
°

O
`c
0

0
0

0
0
0
0

0
0

0
0

f
o
'

N
0
0
0

r

0

"

?
,. O 0 6 ?
? ?
?i 6 a
r 0 0 0 0 6 t
1
nj O
c0 O
0 ?° Q
N g
0 O
0 O
0 h
m p ?-

- - - - -

C
? - - -- - - - - - - -
y
of
y

Q.
m 'o
f
?3 w 00

d d
to
?
o
0
o
0
o
N
o°
O
o
O
D
o
e
3°
0
0
0
o
a
o
a°
0
0
0
G
to
a..
0
6
0
10
i
O
6 O
0 O
0 O
0 O
0 O
O P
0 0
0 0
0 0
0 0
6 Q
0 O
0 g
0 0
0
O
L

o c;

w
M M

iD N
A
m ?
H O
L'I

? 4 ? o ? A ° ? ro a ° b ?' ?
tU . ? G p? o o 0.

C5 ro
° E a
n E in c
m 4 to
: :
s 3 d o ? a " a
c

d
U
a
a
Q
Q
O
d

co

d
i
n
?
1 © ? r N
?fl d
d 1 0 ?^ N O

77

x A I 00
tp
C
C
E
,

W

1 ?

..
co O
N
N

in
j

O

LU
O
O
f
N
te ; am
o

Y - - - - - - - - - - - - - - -
w
"15
N ? 0 0 4 4 0 O O O O O 0 0 0 0 0 0 0 0 0
2
.

0
0
?-
M
C7
[`
O
O
O
O
O
H
oo
N
O
v1
??j
'?
0
0
0 i
`f ?: <

d :?
M
M w
N
N
In
r`
'V
C
d C
i

QS
w

}

C

(a 1

J
N {yn?
$
a
w
c
p
d
a d
T
s
ro od
ti
cL d ?' 0.H " i
,p t1 N U O d ` ..Q N ty ro
Q
a a a

C "' c O IV
SI
?
4r
G.
r
?N
StS

f y JJ y - p

E ro

E ? ;c

E
?
O
OS
ro
ft
4
$ RS
A d V) 5 vs Opt
QOM o c U a ? ¢<t
p
a°
i^ a
A
S
S
3
3
3
h
1
i
i.
c
?Ic
G}
ti
a
0
9
U
u
0.

r l j ,

L L L L !

'
IL
L
?
I it L
: I
L - , H ,
I. -

j P t) f
f
1 Q ?
'
_ L L L L L , L g

,
0 3?
! _ iY L

s ' s

I h i i n i r a
m
Q ?
'
O

3 -7
I

m 3 ? c a u
i 8
y O Q O: Q C it m S a

,
0
cr
ut
:X
c5
>
?I
?° c3a
l
z
N n
d
`z
d
U1 A
? U
0 W U
O
m ? V
h .? E
N ,'?p r
N N J
to d
7
a C v
E m
N N C
4 ? a
? G O
p o 0.
p O `o
v 8
N N
y h O.
r ip
3 j 1C.5
' a
d
N a
r y ?
1?
ti y Z
N
630
K a a
Mecklenburg County Site Evaluation Tool - Site Performance Analysis
North Lake Business Park Phase
Town of Huntersville
#3716
Land Use Summary
Total Site Area (acres) 8.4
Pre-development impervious percentage OA%
Post-development impervious percentage 29.8%
Annual Hydrology Summary
Existing Design Design
Landuse without BMPs with BMPs
Annual Surface Runoff (inchesJyr) 2.66 12.95 7.25
Annual Infiltration (inchesJyr) 7.80 5.27 6.17
Storm Event Runoff Volume and Target Summary
Runoff Volume (ac-ft) Existing Design BMP Storage Tang, t Meets
Landuse without BMPs Volume Goal?
1-yr 24-hr storm 0.341 0.755 0.459 0.414 Yes
1 yr 24 hr?
l inch 04 _
2-yr 24-hr
Storm Event o s Storm Event
Not Selected ° Not Selected
01 -
00
Cap Vol Target
Peak Flow and Hydrograph Summary
Existing Design Design Meets
Landuse Without BMPs with BMPs Source Target Goal?
2-yr 24-hr storm (cfs) 9.61 26.63 1.29 User-defined 9.61 Yes
10-yr 24-hr storm (cfs) 24.43 49.37 1.94 User-defined 24.43 Yes
....
_
3C - - 2-yr 24 hr storm - --
5 _Posts, no SMP
20
-Existing
-Post, with BMPs
U _. . _ .. ..... ...........
6 00 AM 9,00 AM 12:00 PM 3 06 Phi S ri, PM 9 66 P1,11 12.06 AM 3.00 AM
i0-yr 24 hr storm - - ---
_ ...,,.Post. no 81APs I
40 ....... ._........ ..r"""°'" Existing
30 -Post. with 81APs
20
10 h 7,0 AM M,-, Am 12 00 P111 3 00 ?hi 6 PIC Ph? 9.66 A'l 12.60 AM.
3'00 APA
•
•
•
•
_................. _._._
Mecklenburg County Site Evaluation Fool d Site Performance Analysis
North Lake Business Park Phase
Town of Huntersville
#3716
Annual Pollutant Load and Target Surnmmary
Total Total
Target Evaluation Sediment Phosphorus Nitrogen
(developed portion of sites (tonlyr) (ihlyr) (rbtyr)
Design without BMPs 4.54 10.5 73
Design with BMPs 144 2.6 33
Target Removal 85.0% 70.0% 45.0%
A„hi=cved Rz?niovaa 9013 .« 75.2'-:, 55,Vt
Meets Goal? Yes Yes Yes
Additional load from undeveloped 0.61 0.5 2
areas removed by BMPs
Sediment Load
(devel. portion of site)
5 00
4.00
3.00
2.00
1.00
000
Total Total Fecal
Entire Site Annual Load Sediment Phosphorus Nitrogen Coliform
(tonlyr) (iblyr) (iblyr) (#x 10elyr)
Existing Landuse 1.27 3.0 19 33
Design without BMPs 5.25 12.4 85 234
Design with BMPs 0.55 4.2 44 32
40
2.0
00
Nitrogen Load
+00
80
00
40
20
Areal Load in Rates Sediment Phosphorus Nitrogen Conform
(tontaclyr) (Pblaclyr) (Ibla¢tyr) (# x 110'taclyr)
Existing Landuse 0.151 0.36 2.29 3.9
Design without BMPs 0.625 1.40 10.15 33.8
Design with BMPs 0,065 0.50 5.27 3.9
Nitrogen Load
(dove). pottion of site)
Northlake Business Park =DIWW_TAW W4W
PROJECT 3716 BY: BLW i"I'm AXA&KImbT `mw6l, `N "`?;m-aD2m
PJ?*
Qw

DATE: 91512007
T. M.: DBS r Try
&' Skme
?raRarypc
REVISED: 11212008 P.M.: DDS RAIN GARDEN VOLUMES
RG-A1 1,337 FT3
RG-A2 1,460 FT3
RG-A3 234 FT3
RG-A4 491 FT3
RG-A5 200 FT3
TOTAL 3,722 FT3
RG-Al
,v?ofxom
Updated for
O
(?d
' yy¦a 1-
'
!
Rai
?
NC
BMP
Manual ? f
n i
.??i?
a
men
as Amended l!
J
....
i
-?
--?

Rv = runoff coefficient (Runoff/Rainfall)
RV = 0.05 + 0.009( 11
Rv = Volumetnc Runoe Ooi ffl ent Fur. iRdlnrall)
% Impe,-s ater gualay Protection Volume
("Simple Method" - Schueler, 1987) WQv= 1.0"RvA
NCDENR Manual Juty 2007 pg. 33 12
Meck. Cly. aMP Manual pg. 3.2
Fill in Values:
Percent Impervious of Site
Acres 5 Acre Maximum
Rv = 0
Answer:
SCS WQv = 0.072 Ac. Ft.
Method 2726 31 1 Ft.a
CF
Insert 1.56 CFS Peak Flow for 1"- 6 Hr. Storm
t8 Length of Level Spreader for 1" @ 1 fps
?fff(?''????
K?a re
Formula:
Af = (WQv) (Df) Where:
((k) (Hf+Df) (TT)) Af = Surface area of Rain Garden (S.F.)
From Georgia Design Manual WQv = Water Quality Volume to be Captured
Section 12.16 Df = Filter Bed Depth ( 2 feet min. for grasses, 3 to 4 feet for trees)
(Based on Darcy 's Law) k = permeability coefficient of filter media (use 1 Ft./Day for amended soil mix)
Maryland Design Manual ' See Maryland Stornwater Design Manual, Page 3.40
Page 3.40 Hf = Average height of water above filter bed (Mulch)
(use 3 to 6 inches, which isone-haft of 6" to 12" ponding depth)
Tf = Design filter bed drain time in days
*MAXIMUM 2 Days, lUse 1 Day 1
4
?1i_I_I?ly ?J
Rv= 0.95
WQv= 0.95 inches
CNm= 99?f. Use to compute Qj-
Fill in Val ues:
Soil Type K (in./hr.) K (Ft/Day)
W- = 1 Ft./Day` Sand 6 12
Df = 3 Feet Loamy Sand 2 4
Hf = 6 inches Sandy Loam • 0.5 - 1 1 - 2 'Use 0.5 1 Ft ;Day
Tf = 2 Days° Silt Loam 0.02 0.05

Af = 13 SF Required assuming infiltration durin g rainfall
3121 SF Req. by DENR Manual (Vol./Depth)
29.4 SF Impervious Per SF of Rain Garden 3.39 % of impervious site
26 Width Approximate Size
52 Le Can Be Freeform is Shape
®Depth from top o w er s o Inve o f underdrain.
Water Draw Through Rate
Darcy's Equation:
Q = (.0000232)'K'A'( H/L) -- Q = 0.0207 cfs
Where:
Q = Flow (Rate of Draw) through Bioretention Soil (cfs)
K = Hydraulic Conductivity of soil (in./hr.) ( Usually 1/2"/Hour)
A = Surface Area of Bio-Retention Area (SF)
H = Height of Water above Drainage Pipe (Undercrain)
L - Thickness of Soil Bed (Minimum 3' for Trees, 2' for Shrubs )
Assume ( H/L I - 1
Time to Drawdown water from Inundation to Saturation at Surface:
Volunri 64655 Seconds
16.0 Hours to Saturation
Time to lower Water Table to 2.0 feet below surface:
Assume 40% Porosity
Volume =Area x 2'x 0.40
1070.0 Cubic Feet
51724 Seconds
= 14.4 Hours to Lower Water 2' below surface
32.3 Hours to Draw Water Through Soil Layer
As a rule of thumb, the length of underdrain is based on 10% of Af
Source. (NY State Stormwater Manual)
L = 45 Feet in 3' wide stone bed
Required Diameter 5.0 Inches Minimum 6Inches 1 Use PVC or "Double Wall" Slotted HDPE
Source. (NCSU Rain Garden Design Worksheet, Bill Hunt, PHD)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
t
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Or More Untlerdrains required
Minimum of 2 Untlerdrains

Excavation $2.972.16
Stone Bedding $272.45
6., HDPE Pipe $334.37
6., Cleanout $250.00
Filter Fabric $594.43
Soil Mix $5,052.67
Mulch $817.34
Plants $1,611.97
Cost $11,9116.3
CTSt SF
MCost I SF
Impervious
RG-A2
Updated for 2007
(
e
ShN
R
NCDENR BMP Manual i
m
u
.
iq
,
as Amended M
.
.
-j --?
111r 1 r. r,
Rv = runoff coefficient (Runoff/Rainfall)
Rv = 0.05 + 0.009( 11
Rv = Volumetric Runde Coeficlent (Ruroff,Rainfall)
"I" = % Impervious
ate, Quality Protection V,17
("Simple Method" - Schueler, 1987) WQv = 1.0"RvA
NCDENR Manual July 2007 xi 3.3 12
Mack. Cly. BMP Manual pg. 3.2
Fill in Values:
"I" = 100 Percent Impervious of Site
"A'. = 0 b7b Acres 5 Acre Maximum
Rv = 960
Answer:
SCS WQv = 0.07b Ac. Ft.
Method 2976 3406 Ft.'
CF
Insert 1.69 CFS Peak Flow for 1"- 6 Hr. Stone
20 Length of Level Spreader for 11 fps
Item Alen
Formula:
Af = tWQvl (Dfl Where:
((k) (Hf+Df) (Tf)) Af = Surface area of Rain Garden (S.F.)
From Georgia Design Manual WQv = Water Quality Volume to be Captured
Section 3.2.3.6 Df = Fitter Bed Depth ( 2 feet min. for grasses, 3 to 4 feet for trees)
(Based on Darcy', Law) k = permeability coefficient of filter media (use 1 Ft./Day for amended soil mix)
Maryland Design Manual ' See Maryland Sto-water Design Manual, Page 3.40
Page 3.40 Hf = Average height of water above filter bed (Mulch)
(use 3 to 6 inches, which isone-halt of 6" to 12" ponding depth)
Tf = Design filter bed drain time in days
*MAXIMUM 2 Days, (Use 1 Day 1
Fill in Val ues:
"k" = Ft./Day"
Df = Feet
Hf = ?1 inches

Tf = 1[hli
Af =

Water Draw Through Rate:
Darcy's Equation:
Q = (.0000232)'K-A'( H/L )
Where:
Q = Flow (Rate of Draw) through Bioretention Soil (cfs)
K = Hydraulic Conductivity of soil (in./hr.) ( Usually 1/2"[Hour)
A = Surface Area of Bio-Retention Area (SF)
H = Height of Water above Drainage Pipe (Underdrain)
L = Thickness of Soil Bed (Minimum 3' for Trees, 2' for Shrubs )
Assume ( H/L) - 1
Q = 0.0226 cfs
Time to Drawdown water from Inundation to Saturation at Surface:
Volume/Q: 64655 Seconds
18.0 Hours to Saturation
Time to lower Water Table to 2.0 feet below surface
Assume 40% Porosity
Volume = Area x 2'x 0.40
Rv= 0.95
WQv= 0.95 inches
CNm= 99,6 Use to compute Q1.
Us,, 0.5 1,, 1 Ft 1).y I
3.39 % of impervious site
1167.9 Cubic Feet
51724 Seconds
14.4 Hours to Lower Water 2' below surface
32.3 Hours to Draw Water Through Soil Layer
II?fj,l _tl1 ?, -+j
As a rule of thumb, the length of underdrain is based on 10% of Af
Source: (NV State Stomrnater Manual)
L = 49 Feet in 3' wide stone bed
Required Diameter 5.1 Inches (Minimum 6Inches 1 Use PVC or "Double Wall" Slotted HDPE
Source: (NCSU Rain Garden Design Worksheet, Bill Hunt, PHD)
Soil Type K (in./hr.) K (Ft/Day)
Santl
Loamy Sand 6
2 2
4
Sandy Loam ' 0.5 - 1 1 - 2
Silt Loam 0.02 0.05
_IMSF Required assuming infiltration during rainfall
340 SF Req. by DENR Manual (Vol./Depth)
X29.4 SF Impervious Per SF of Rain Garden
27 Width Aooroximate Site
54 Length Can Be Freeform is Shape
?$, Depth from top o water surface to invert of undenlrain.
Or More Underdrains required
Minimum of 2 Underdrains
xNU cueoew, ao-rtc^,ctrrtt? >uw
1
4
o,

Excavation $3,244.09
Stone Bedding $297.37
6" HDPE Pipe $364.96
6" Cleanout $250.00
Filter Fabric $648.82
Soil Mix $5,514.95
Mulch $892.12
Plants $1,759.45
Cost $12971.7
CosVSF $8.89
Cost / SF
Impervious
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
s
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Lit
UU??
M
N
C w
fx U
O
00
CA
W
a
y
n w
I I ? U
C ? V
(0 to (O
? - OD
E O
O O
L U)
O O O
(6 = co
L O
N

ca
O
O n
o U)
c
U l CD E
F .T- a) x Q O
m ? o (D (0 C7 O CD c
a
a a'- o o II
c
N Nai o O o>
a

0 7 L C FU
`Y) "c m o
-

? O
? ?
c
d
M O Q
? N
CL 6 U
C N
O m II U) W
In U a) O E
E

m"
N in
2 O II II a) N
U)
i LLUQ a O 05 <

W
)
LLJ LU
0 0 Q W
Z; a O Of
x
O
a)
3
N
r
L
3
a)
U x
o
o m
a?
o ?
7 a
to
a)
U O
O
O
a)
C
o a
U C
a) ca
a?
ca N N
oc
U
o 3
OC) °) o a
a
O
II (6
L a
a ?
? II N
2 c3
3
0
Lq
N U
N ( O
2 N
7
O
(D
a
m
m
2 L
O
RG-A3
1lnbnos7
Updated to r
O r M w /
l
S

NCDENR BMP
Manual
(
I
i1filt
as Amended -j ?-'-'

Rv = runoff coefficient (Runoff/Rainfall)
Rv = 0.05 , 0.009(l)
Rv = Volumetric Runoff Coefiraent (Runoff/Rainfall)
% Impervious aler Dualtly Protection Volume
("Simple Method" - Schueler, 1987) WON = 1.0"RYA
NCDENR Manual July 2007 pg. 33 12
Meck. Cty. BMP Manual pg. 3.2
Fill in Values:
"I" = 100 Percent Impervious of Site
"A" = 1 Acres 5 Acre Maximum
Rv - 50
Answer:
SCS Wav = 0.013
Ac. Ft.
Methotl 512 9
5 6 Ft.'
CF
Insert 0.29 CFS Peak Flow for 1". 6 Hr. Storm
Length of Level Spreader for 1" 1 fps
t(??
8(?? A ?f?y
Formula:
Af= (WQv)(Dfl Where:
((k) (Hf+Df) (Tf)) At = Surface area of Rain Garden (S.F.)
From Georgia Design Manual WQv = Water Quality Volume to be Captured
Section 3.2.3.6 Or = Fitter Bed Depth ( 2 feet min. for grasses, 3 to 4 feet for trees)
(Based on Darcy's Law) k = permeability coefficient of filter media (use 1 FL/Day for amended soil mix)
Maryland Design Manual " See Maryland Stormwater Design Manual, Page 3.40
Page 3.40 Hf = Average height of water above filter bed (Mulch)
(use 3 to 6 inches, which isone-hare of 6- to 12" pending depth)
Tf = Design filter bed drain time in days
*MAXIMUM 2 Days, (Use 1 Day)
Rv= 0.95
WQv= 0.96 inches
CNm=®Use to compute a(.
Fill in Values:
Soil Type K (in./hr.) K (Ft/Day)
"k" = 1 Ft. /Day' Sand 6 12
Of = 2 Feet Loamy Sand 2 4
Hf= 6inches Sandy Loam 0.5-1 1-2 Vtse 0.5"Hr,1-'t,Day
Tf = Z Days` Silt Loam 0.02 0.05
?:?(?lldCt,tJf - ?
Af = SF Required assuming infiltration during rainfall
68 SF Req. by DENR Manual (Vol./Depth)
06 SF Impervious Per SF of Rain Garden 3.17 % of impervious site
11 Width A92roximate Size
22 Le In Can Be Freeform is Shape
Depth from top o w l r u ce R.9 of underdrain.
Water Drew Through Rate
Darcy's Equation:
Q = (.0000232)'K'A'( HIL) Q = 0.0041 cfs
Where:
Q = Flow (Rate of Draw) through Bioretention Soil (cfs)
K = Hydraulic Conductivity of soil (in./hr.) ( Usually 112"/Hour)
A = Surface Area of Bio-Retention Area (SF)
H = Height of Water above Drainage Pipe (Underdrain)
L = Thickness of Soil Bed (Minimum T for Trees, T for Shrubs )
Assume ( H/L ) - 1
Time to Drawdown water from Inundation to Saturation at Surface:
Volume/Q: 57471 Seconds
16.0 Hours to Saturation
Time to lower Water Table to 2.0 feet below surface
Assume 40% Porosity
Volume = Area x 2'x 0.40
187.6 Cubic Feet
45977 Seconds
12.8 Hours to Lower Water 2' below surface
28.7 Hours to Draw Water Through Soil Layer
11-!f i
As a rule of thumb, the length of underdrain is based on 10% of At
Source: (NV State Stormwater Manual)
L = 8 Feet in 3' wide stone bed
Required Diameter 2.7 Inches (Minimum 6Inches 1 Use PVC or "Double Wall" Slotted HOPE
Source- (NCSU Rain Garden Design Worksheet, Bill Hunt, PHD)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Or More Underdrains required
Minimum of 2 Underdrains
RN.\' GIRDLM < INtiRtTlHil(XI AAf'.?.

Excavation $390.81
Stone Bedding $47.77
6" HDPE Pipe $58.62
6" Cleanout $250.00
Filter Fabric $104.22
Soil Mix $590.56
Mulch $143.30
Plants $282.61
Cost $1,867.
CosVSF $7.97
Cost / SF
Impervious
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
0

a
(n
c
w 3
U -

M
O
I I
a
L
3
a?
U
X
"- O
O co

A C
N ?
O Q
II U _
?
C P N 00
O

m O
00

M ). L

> m
N > N

L O
cD o O O
(0 = m
0)
L O (D
C
3
` is s
v -
? v
m
m
U II c a)
p N
c
. E 2 L
? m Q O Q
ns
a

?
N
C E
a
o
a)
v
cfl U
o
l
3

C c
O C -2 C
) m
m 0 O': o I I O CL
a
ai X a m

ai c
r>
) o
iv
0
o
Q L a c s II m
m II U W
~
E U O E
U

O O ?
11
11 En
O w
N y
O w m
O II a>
N
LL 1L U Q 0 o C/) Q O S a D
O
LL
O
U
O
N
7
O
V
RG-A4
Updated for 2007 "
1

MP Manual
NCDENR
a (
R t Gat d
on 3
A
as Amended
.
,
? i 9?>ta? Ar

Rv = runoff coefficient (Runoff/Rainfall)
Rv=0.05+0.009(1)
Rv - Volumetric RunoHC-Lent (R-H/Ramlall)
Impervious ater 0-Ifty Protecb- Volume
("Simple Method" - Schueler, 1987) WQv = 1.0"RVA
NCDENR Manual July 2007 pg. }3 12
Meck. Cty. BMP Manual pg. 3.2
Fill in Values:
"I" = 100 Percent Impervious of Site
Acres 5 Acre Maximum
Rv = 0.950
Answer:
SCS WQv = 0.028 Ac. Ft.
I Method 1072 1 28 FLa
CF
Insert 0.61 CFS Peak Flow for 1"- 6 Hr. Stone
7 Length of Level Spreader for 1" @1 fps

Formula:
Af = IWQv11Df) Where:
((k) (Hf-Df) (Tf)) Af = Surface area of Rain Garden (S.F.)
From Georgia Design Manual WQv = Water Quality Volume to be Captured
Section 3.2.3.6 Df = Filter Bed Depth ( 2 feet min. for grasses, 3 to 4 feet for trees)
(Based on Darcy's Law) k = permeability coefficient of filter media (use 1 FtJDay for amended soil mix)
Maryland Design Manual ' See Maryland Stormwater Design Manual, Page 3.40
Page 3.40 Hf = Average height of water above filter bed (Mulch)
(use 3 to 6 inches, which isone-half of 6" to 12" ponding depth)
Tf = Design filter bed drain time in days
• MAXIMUM 2 Days,lUSe 1 Day 1
Fill in Values:
"k" - 1 Ft./Day'
Df = 2 Feet
Hf = 6inches
Tf = 2 Days'
Soil Type K (in./hr.) K (Ft/Day)
Sand
Loamy Sand 6
2 12
4
Sandy Loam -75-1 1-2
Silt Loam 0.02 0.05
Rv- 0.95
WQv= 0.95 inches
CNnl Use to compute Qt-
lA Se 0.5 "rh{r, 1 Fk :Day
81,1111411,41 ?I )?
At = 49 SF Required assuming infiltration during rainfall
122 SF Req. by DENR Manual (Vol./Depth)
31.5 SF Impervious Per SF of Rain Garden 3.17 % of impervious site
16 Width Approximate Size
31 Length Can Be Freeform is Shape
Depth from top o water surface to invert of underdrain.
Water Draw Through Rate
Darcy's Equation:
Q = (.0000212)'K'A-( H/L) Q = 0.0086 cfa
Where:
Q = Flow (Rate of Draw) through Bionetention Soil (cfs)
K = Hydraulic Conductivity of soil (in./hr.) ( Usually 1/2"[Hour)
A=S ` rface Area of Bio-Retention Area (SF)
H = Height of Water above Drainage Pipe (Underdram)
L = Thickness of Soil Bed (Minimum 1' for Trees, 2- for Shrubs )
Assume I H/L) - 1
Time to Drawdown water from Inundation to Saturation at Surface:
Volume/Q: 57471 Seconds
16.0 Hours to Saturation
Time to lower Water Table to 2.0 feet below surface:
Assume 40% Porosity
Volume = Area x 2'x 0.40
= 392.8 Cubic Feet
45977 Seconds
12.8 Hours to Lower Water 2' below surface
25.7 Hours to Draw Water Through Soil Layer
rlr
As a rule of thumb, the length of underc rain is based on 10% of Af
Source: (NY State Stomnvater M16.
L = 18 Feet in 3' Required Diameter 3.6 Inches (Minimum 6 Inches 1 Use PVC or "Double Wall" Slotted HDPE
Source: (NCSU Rain Garden Design Worksheet, Bill Hunt, PHD)
Or More Underdrains required
Minimum of 2 Underdrains
yf ? ?a
VF i sue!.' .++P$ ,:?L.
r-
-??`C-
Excavation $818.41
Stone Bedding $100.03
6" HDPE Pipe $122.76
6" Cleanout $250.00
Fitter Fabnc $218.24
Soil Mix $1,236.71
Mulch $300.08
Plants $591.83
cost $3,638.
CosUSF $7.41
Cost I SF
Impervious
?g;
M
?f
m
Sim
W
Q.
CO
ca IZ
m ? 0
m
` H a
a
= i co
M N
? N
m N
U Diu
'C L ui
Lij
Z a p
w
U
0)
M
N
I I
A C
I I ?
C
O ?
a
? O
o (l)
L ?
cD 0
0
m=
L ?p
m
o E
T N
N ?
mCO?o
c ?
? N
ce)
4
Q ?
m I I
? U
E
0 II II
Ii LL U Q
U
0)
M
N
11
x
m
E
O
0
0
X
N
a
N
C
N
O

L
v
v
Q
0
u
C?
C
0
R
6
W
U
O
x
0
[0
N
a
N
E
O
a?
-o
m
c
0
U
i
O
N
N
i?
U
O
0
0
c
U
a?
O
L
m
(0 LO
6
x
0
a
rn
c
N
W)
N
r
L_
3
a?
U
w
m
o
0
f

?
o a
C/)
tD t0
_ N U
Q ?
? O
Y ?
= N
Q
3
O
cD
4
U
v
C9
0
c
I I
C I I L
E v a
? I I
Q 0 2 C3
a
c
m
N
m
d
3
N
a
.a
0
cu
Go
N
to
Z)
m
m
= L
a?
0
O
'1
?.
tl,
?l E
1 IIV-6 HR Storm
Analysis
RG-A1-V-6hr
r?
©t.10
RG-A2-1 "-6hr
0
RG-A3-1 "-6HR
RG-A 4-1 "-6HR
crQ??

Out 20
Out 30
Out 40

71 Y: ... _u .
-- ,
Page 1.01

.
Total
21c=-_ Rai 17 __-
_.. ?n N T
------------ ------ --- ------------
_ Rainfall
a„ -o-. acg- °.?
e,:3-on;
i
_ i33 =canor. .. . _, _xR i
Max
--------- -------- ---------
1A. 30 1. 13
156. 1.40
.., rw
As. : 3 .82
1.4._", .29
01 1.63
MAO 1.42
131. Oa . I C",
15C. A 62
13c:3 .21.-1

..
m _ 3 7: _...
-35
P,:.

.," H 1 " .a_....a_,,,
....r . Tzrig '`'M.,,.,, 1
------------------- - -------------- -------------------------------------
L-Ita Type, «i.lr. 1D = Mm" Depth C". v.'e
_., ain all 7 C 1?I
.. w. '?..L07, X11 .t 1?_ :. .,.
__ • g Du: a -a - .010 ra.ara
r...w ._ g tart me 0 min 3 t- p= 5 . 0C, .ruin F.rcl.? ?.,._..'0 m.n
aw_.W
3.J_.

...........

y m-=t .
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
To--al Tc: 5.00 min

Tt _
. ,.. - 'x._12 ... .. ?..+ ?.

rv
- - - - - - - - - - - - - - - - - -- --- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
94 I si.,_.,
-1E- c5F _._^s & ET-zHTE' . µ1V

u
.pia.... tt. L__ .__..
a. ?z . ,_

_. ? ?_ a rw_._u
------------- -------------------- ----- --------- --- ----- - - - - - -

-p e n f f _ . .. x

a _1. .. __... s ora M.. u _re_
-------------------- ---- --------- - ----- ------
a 1"
`_ i

_ -a

i : u
-3 c "N
------------------- --------- -- --------- ------
. 10 51 ;6

.._ ,. . =' s t
.x ?. _

p . .. .,. _, ..i
:.1S
r fa 1'^,,. ac r ?c
F .....i ------
an i s - w "` .'oTn _ r _. >.::.3 ,z. _.._ 's' x r.:..3 4

?a _^:a r?
\: n

•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Attachments
(fw
Y
f'
r
/f

t?
l?

r

Q5

?

U5
) V) Ql
3
Z. C O ?Y)
LL F CV
.
W ?
cv U) ? x
CL r') h
7
N
fl1 CLl tYD l CT3 ?
n
N as
N --
c'Q
a) cv ce ca C K
R
A

?
} n ° p ra
. s
_ c c-

d ( 1 ! ! ? c a) OD
± _
? a
v a? c: v
! (
L t C3 cm iV as r
a
L I f V {
a

LSJ # ra rz5 zs ca z
_11 3 ( i 0 4j L >
nit
W

T?
5
V ?
Q1
H
ill
Q
M
CSR
O
2
u
w
a
a
L.L
Q
t-t9t: 1_?I `Gztuxl?irl?;i'W?i ?a<. c! 's Poy''hna„ 1r?:e lti41£S<?tlt.;li:HSii`ii: .?
0000000000000000000000000000000000000000000

N
H
J U)
T U3 J a °
(y/ z W
0
Z m cif
,?G d
?e CL
'< uo?.
...1
d ov?i _ LU
'
Lu
. 4 L3 a
i
^
Lij
O
F is
i.3
}
ce
LL Vf
0 / ,?}
y .i
w W Q. 4 _ E

i

'^
a .. er- 2 4 0 f.i Il..iif tl M S C! ?,
S t, i, t t
SSS +
K
4
?F t
jet t
W - - ,
r w
?. ac
w
w [G"
Uj ;
cnt--?
1
J
?QD S vi °"
f!;
can a°
zwc?2? )
i j
i- e
.r ca 0 ?t9 G ? ?¢¢
M mm
x V,4
a rd V--BOO. y O Y?
,x ZK,
z}n NA;._l_usSn; 34
ID <
t - 1 . 'G k T.
l
![5b ':':S `pe<.t6tiFtue7 Nl fi>p; lRjdR?f?t "m'i I In YCi )MOUE 9f!E L i(VWPOUA,,v( 1-

R? ? C
CLC ? Is
Y V p C
p
UJI
U
y W C Z
F- z XvY
ce Cl) w <-
0
zm0-::x
w
u
ce.
Q % a N e
€L"0C
4
1
?r
X
m
4
?X
4
I
1
1
tt,
"i
d?
a
---------------------

e
.. M.i Y.W.IR YI....+R.. ?•..S?. M.fM}
r q w
a
Q
17
w1?......... ?..s, ? ..?... f ?
# a 1
1
4i
i
pp?
3(i i 1

tl
m '
i
I
a? tl

-1.
I
?,S

K"stl •}
7
43 ? $ G
yr+, y M
E
s+?4 ! YY p O
x?
?.1
:J
a (ji
„J Z
-? 0-
t tL
< )
_ t!1
a a
._t tla z
IJJ z
q????II y???{
bi V ? iS Q m
q=yyI?>y }Q?yy G
6d?f 6wL r S
y
Q.'
LU
CD
L11 - c
r <
a-
?
•S
.
><i7 ?? A 1 Q tl.
LL?
J < Vll? "T,
<11J
<
LL <
- ECY}
W _
r
Y
r ?
LU

tLt

Cry
_>
Q
?
C5 Gk.
0
CL
a
Z
tii
0
Ld
a

n ,.
c <e>

W a] x rr'p >si

0000000000000000000000000000000000000000000