20080347 Ver 1_More Info Received_20080415

ENVIRONMENTAL SERVICES, INC.
524 S. NEW HOPE ROAD
RALEIGH, NORTH CAROLINA 27610
919-212-1760 • FAX [phone]
www.environmentalservicesinc.com
April 15, 2008
Ms. Cyndi Karoly
NCDWQ
Wetlands/401 Unit
2321 Crabtree Blvd., Suite 250
Raleigh, NC 27604
Re: Brookwood Capital
DWQ# 08-0347
Ms. Karoly:
ESI is submitting the enclosed information on behalf of the applicant (Brookwood
Capital) and the project engineer (Advanced Civil Design). Five copies of the requested.
information are being provided, and I trust that this will allow DWQ to continue
reviewing and processing the 401 application.
Please call me if you have any questions or comments. Thank you for your assistance
with this project.
Sincerely,
Environmental ervices, Inc.
,~~ -
e fHarbour, P W S
Asst. Vice President
Attachments
~.~ ~~ < ~ ~
- .. .
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~ ~n~~
~ tJjf~
~~TiANDS,4ND SYDE~~9~/,q~; ~~l d"sr"y~,~
FLORIDA • GEORGIA • NORTH CAROLINA • SOUTH CAROLINA • MARYLAND • OHIO

NEW HOPE
DEVELOPMENT
STORM WATER CONTROL
NARRITIVE AND CALCULATIONS
Apri18, 2008
;```~~ii~1 a rig, ~
\~,~ ~N CARp~ `''s
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~''C~YA.' ~Nl~~~. LANDS,~NDS"t;:i;~r.;,'... ;;~ct

•
New Hope Development
STORM WATER REPORT
TABLE OF CONTENT S
• Section 1 -Runoff and Detention Pond Design and Calculations
• Section 2 -Storm Drainage Design and Calculations
• Section 3 -Miscellaneous Maps and Images
~~

1
New Hope Development
STORM WATER REPORT
Section 1
RUNOFF AND DETENTION
POND DESIGN AND CALCULAT
IONS
~~

~~/~ rrr
1 V ~ E
117 Centrewest C
ngineering, Inc. ourt
Cary, NC 27313-2013
~'v'~ F'"8a"`"' ~ La7~Yors Phone: [phone]
Fax:[phone]
New Hope Development -Storm water Analysis
Apri18, 2008
Narrative and Calculations
The referenced site is located off of New Hope Road between US64 Highway and the
Crabtree creek in Raleigh, North Cazolina. The site is bound to the north by the
Crabtree Creek and there aze two main perennial streams that flow through the property
from south to north and discharge in the creek. The Crabtree Creek is part of the Neuse
River watershed .The site is currently a vacant lot and is light to densely wooded with
no significant ground cover.
The proposed development is to extend global street from the eastern property line
about 600 to a dead end cul-de-sac. At the present time, a 150,000 sq warehouse with
associated parking and truck loading azeas is proposed at the end of the cul-de-sac.
There is no development proposed on the remaining land, but it was assumed that these
areas will be developed in the future with 85% of the azea being impervious surface.
By analyzing the existing topography of the site, it was determined that there is one
main discharge point for the site and is labeled as Dischazge Point `A' on the included
pre-development drainage plan. For this analysis, the site was divided into three
sections; Drainage Area `A', Drainage Area `B, and Drainage Area `C'. Drainage Area
`A' includes all of the azea between the two perennial streams. Drainage Areas `B' and
`C' are located between the eastern property line and the eastern most perennial stream
and is divided by the future road. These areas can also be found on the attached pre-
development drainage plan. Ultimate discharge points were determined were storm
water will leave each one of the drainage areas. The three Ultimate Discharge points
can be found on the attached pre-development drainage plan.
In order to not impact any downstream areas ~~ this proposed and future
construction, pre-development and post-development flow rates for each discharge
points must be determined. The existing 1-yr, 2-yr, and 10-yr rates as well as the
existing Times of Concentrations and Weighted Curve Numbers were determined using
the TR-55 method as published by the United States Department of Agriculture, titled
Urban Hydrology for Small Watersheds, and the results aze shown on the following
pages:

1
t8
N€1NHOPE DEVFLOOPAIE
EXISTING WEIDHTED CURVE N NT EXIST7A7p p/erwA
• r~=-- Re nn.
LAND USE
~~ ~) ~
BUILDING (scree)
0.00 98.00
PAVEMENT
0.00 98.00
GRAS6
20.59 63.Op
TOTAL AREA (HSG B 8 C, wootled)
20.59
Time M Corx:entratlon R.X
T,= 0997 •(n•L)a~znf •a0..
whxa:
SepmaM t
L=Ebw LarWlh =

n = mannbm rouphnd coaR. 75 R
0
4
Pr= 2 year, 24 hour rainh0 .
3.5 N
e = abpe of hydralk grade Ilns 0.080 RRI
T"
o.1ss nr
Sepmam 2
ShotlowConcentrated Elver
T,sL/3800•V
L = Fbw Lenp0l =

V = VsbcBy 802 R

• = abpa of hydralk grade Bna 8.25 Rhec

T`f 0.110 RRt
0.032 M
SepmaM 3
Open Channel Row
V=1.49 •rm•s1eln
where:
r=alp,~=hydra0c radius OA90R
a =lbw area 14 R~
R. ° welted Perlmaler 28.58 R
e = channel ebpe
' 0.004 itAl
n=manninp
a coelL
V= 0.022
T,= L 13600 • V 2.88 Ns
L=
T '
`r 1407 R
0.147 N
T~r+Te,~+Ty
0.335 hr
1-VR PRF-0El ~ OPA.F~RI u.
P=
Curve Numher (CN) = 3.0 h
la = ~
S =1000/CN-10 1.175 h
5.87
O ~L
0.43 h
larP _
Untl Peak Diedfarpe (y)
0.392
(auumkp Type II rebhtl

d'ntrlMdbn) 4B0 am
Orainape area (!~„) 0.0322 ~ ,
Oo=G•A='4,
8.68 ch
2-VR PRF-0El OPa A R IA
P=
Cuero Numher (CN)= 3.6b
la = ~
S = t00WCtd-10 1.175 k1
5.87
O=lP-02~C?
(P+0.8•S) 0.88 h
lalP .
Unit Peak
IOlecharpe (y)
0.338
Type II raNhB
d
t O 580 oam
ietrmu
n
Orainape area (l~) 0.0322 mF

11.88 ch
10-YR PRE-DE t ppMET RUI OFF
P=
Curve Number (CN)= 5.1 N
la = ~
8 =1000ICN_10 7.175 b
S.B7
Q=Ip-0.2•SIx
(P +0.8 • S) 7.57 h
hIP =
UnR Peak Dacha a
ro la,) 0.230
(wumbp Type II rabfaB

dKtrPoUBon) 820 cam
Drabepe uea (A,a 0.0322 mP

37.37 Ms
Ar aT THE WERIHTED WEHaHiF
WelpMad CN~SUM ( 0.00 x 88) + ( 000
98) + ! 2059 63 )
20.58
Webhtad CN = ~
h = 1.175

~.
tsb
NEW NOP~eyELOPMEN
EXISTING WEIONTED CURVE N T EXISTIN nrcrl{pR
UMB r TI'71~ ~~.~u
LAND USE AREA (A) CN
BUILDING (~~)
0.00 08.00
PAVEMENT
0.00 08.00
GRAS6
7.30
83.00
TOTAL AREA (H8G B S C, Ymotled)
7.30
Tkn of Coneentretbn (T,):
T, • 0.007 •(n•L)°s/P~ s. ear
Whsrx
Segment 1
l = Ebw Lenplh 75 R
n=menMpns rouOhMS OOeR 04
Ps=2yee, 24 hour relnh0 3.5b
s = sbpe of hydrelk Ontle Ilne 0.040 RIR
rn' 0.200 hr
SsOmaM 2
Sho-ow Conanlnted Flow,
T,=L/9500•V
L ° Fknv lenOth 364 R
V = Vebe-y= 1.8 Rkeo
s=skpe of hydralk Onde-ne 0.050 R/R
T`s 0.020 hr
SeOment 3
Open Clululel fkw
V•1.40 •rsn•e'R/n
whue:
r • a/p„° hydnOc ndlus 0.400 R
•=sow aru 74 R=
P.=waMd perimeter 28.SOR
s=channalsbpe 0.031 R/II
n = mannln0'a eoeD. 0.022
V
r,=Lr3eoD•v 7.N Ns
L'
T•s 622 R
0.020 M
7". r,a. T~ 0.251 hr
1-VR PRE-0EVELOPM NT RI I _
P =
Curve NUmber(CN)=
3.0 N

M° 03
3 =1000/CN-10 ~ 1.175 N
8.87
D'Ip-p2•S1~
0.43k
(P .0.8•S)
IaIP = 0.382
Un8 Peak DISMvOe (q„)
(auumb0 Type II nbfell 540 am
dklrlbu-on)
Dninape uu(A,,,) 0.0115 mP
0, D • /`" • q= 2.70 eb
2-VR PR -0EV OPM 1.T R
P
Curw Numhar (CN) _
7.6 h

l
= ~
e
S s 1000/CN-10 1.175 b
5.87
O•(P-0.2•SI~ 0.88k
(P~0.8•S)
lalP s 0.335
Una Peak DlsMSrOe (q„)
(aseumbp Type II nbrsll 580 um
d4tributbn)
Dnbspe uee (A•) 0.0115 mP
O,° O • A• • q, 5.03 eh
15.YR PRE-0EVELOPA_ •ET_~1 OPP
P s
Curve NumMr (CN) =
6.1 k

le s 03
1.175 N
S =1000ICN-10 5.87
DsrP.e.2.01' 1.57k
(P ~ 0.8.6)
IaN = 0.230
Unk Peak Discharys 17„)
(aswmb0 Type II nkr~ll 710 esm
dktrkutbn)
DnlneOe area (A•) 0.01 f 6 mP
O•° O • ~• 4• 1250 ob
49LS..LLATE THE WEIGHTED WEIGIITE~•• 1 s 5 -
Weiphbd CN=SUM (. _ ( O.OD x DB 1 . r 000 x
981~r 73BZ 631
7.30
Welyhtsd CN s 83
la • 1.175

ra
NEW HOPE DEVELOPME

EXf$TINO WEIGHTED CURVE N NT EX/S77N[;r r1/cru

UMRE e
r

LAND USE t r n
AREA µ) CN
BUILDING (eens)
0.00 98.00
PAVEMENT
0.00 98.00
GRASS
5.07 63.00
TOTAL AREA (HSG B d C, wooded)
5.07
Tkns M Corx:entratlon R.):
T, ° 0.007 •(n'L)n•/Prm • s~
wham;
SeDmenl 1
L=Fkhv length -

n = manni9ns rouphnea ooe8. 75 R
0
4
Px=2Year.24 hour ninhtl .

s = abpe o1 hydnlb pride Ibe 3.5N
0.053 R/R
Tar 0.184 M
Sa9ment 2
6holbw Concentrated Flaw.
T.=L/3800•V
L Fbw Lanp81 :

V=VabGty= 8228

s =sbpe of hydnlb pride Wa 28 Msao

T`~ 0.034 RRI
0.082 hr
SeOment 3
Open ChanneNkrw
whew:
r=a/0.=hydralie radius 0.490R
a =Raw area 14 Ra
0.=welled perimeter 28.SBR
s = charurN sbpe
' 0.031 RRt
n = manNnp
a coeR. 0
024
V=
T.= L /3800 • V .
8.80 Rh
L=
T 123 R
0.005 hr
T,,r+T~a+T~
0.251 nr
1-YR PRE•DEVFr OP~pA ..•rA
~
p=
CurveNumber(CN): 3.0 N
la = 83
S =1000/CN f0 1.175 h
5.87
O = IF' D 2~c~r
(P+0.8 • S) 0.43 in
la/P =
Unk Peak Disch
aroe (R.)
0.392
(
?u~ ; ype II rainhY 545 am
d
Drainage uaa (1),,,) 0.0079 ml'
Or`O' he' 4,
1.87 eh
2•YR PRE•OE~2LOPMENT R ru
P=
Curve Number (CN) = 3.5 h
la : S3
S = t00WCN•10 7.175 h
5.87
O = IP' o`•~

la?
Unk Peak Discharge (q„) 0:338
(auuming Type II rahhtl 580 am
dlalr6ulion)
Drahags araa (ti,) 0.0322 mF
°°_~ •ti•°•
11.ee aN
•
10•YR PRE DEUCi OPM R NOFE
P=
Curve Number (CN)= 5,1 h
la = 83
5: 100NCN•10 1.175 h
5.87
G=(P--0-2u~:~
(P+0.8•S) 1.57 h
IaIP =
Unit Peak Dkkha a
ro (4,J 0230
(asaumkp Type II nhh8

d'utrbutlan) 820 am
DraYRge uea (Aa 0.0022 ml'
Or=G•q,•q
,
31.37 Us
-° °T THETHE_ NrEIGNT~D WEIDHTEn
Wephtsd CN=SUM (= O.OD x 88) + f 000
+( 507x 63)
5.07
Weightetl CN : B3
la = 1.175

The post development 1-yr, 2-yr, and 10-yr flow rates for each discharge area wh
also analyzed using the TR-55 method. The post-development Times of Concentrat
were assumed to be the minimum, 0.1 hr for this analysis. For the areas that are ion
proposed to be future developed, it was assumed that they would be developed to be
85% impervious surface. The results of the analysis can be found on the followin
pages: g

e
l~
NEW HOPE DEVELOPMFUr_onne..~
E31SDN4.)lYErGN7ED CURVE NUMB a
LAND USE AAEq W CN
BUILDING (•~~+)
9.11 Be.00
PAVEMENT
xe3 3e.35
GRASS
1121 B5.0o
FUTURE DEVELOPMENT (H86 B i C, WOODS, ORA89 COMBO)
AREA /~`~ 37.00
(ASSUME 05%IMPERVIOUS)
TOTAL AREA
72.11
Tlmeof CenFenVatlm RJ:
De. 9.1 w
1•YR POST-0EVF OPM
P•
Curve Number (CN)+
I. • 7'0 h
eD
S ` f000/CN f 0 0.500 N
2.18
O • IL.Q.Z$L'
(P+O.e•S) 1.17 h
IeR+
UNI Peek dedlv3e (y) O.iW
o ~n>~3 Type 11 rainfi9 B50 am

Dnh•3•... cA.) 9.371e mr
a•O ~~'~4'
11.51 ds
1•VR POST-DEV OPM 'T R NO
P+
Curve Numbv (CN)+
la a FF

7.5h
DO
S • f000/CN-f 0 0.500 91
2./e
O•~~~ 1.85h

le/P s
Urie Peek Dkuilv0e (y,) 0,117
(ammkp Type II ninfa9
' a85 csln
d
sk9xdion)
Dnhepe rea (q„) 0.0718 ml'
~~0 ~~'~4' 55.15 c4
t0.VR POST D~ OP6ET Rl 11 n
P.
Cwe Numbv(CN)+
la •

5.1h
e3
S .100WCN•10 0.500 h
x.1e
G • IPA 7.OO h

1~ ~
UNI Peak Dklrhar3e l4I O.OBe
(acaundnp Type II rWnfWl
' 350 Cam
d
•bhuien)
OrWupe area (A„) 0.0311 mY
~eO~A'~4' 101.71 cfs
OA~T`_riE M1EION'fFD WEIOHTF
WNphted CN•SUM 4• I J./1 x 90 1+( 2 08 x Be I I
?Z.11 85 1 t e t 97 1
WN3h1W CN + e0
I• • o.soo

ev
NEW HOPE DEVELOPMENT PROPOCCn me y
EXI$11ND WEIGHTED CURVE Mmc o r
LAND USE AREA (A) CN
(acne)
FUTURE DEVELOPMENT
AREA 7.38 53.00
(ASSUME 88% IMPERVIOUS)
Tbne of Concentration (T°):
Uae 0.1 hr
1•YR POST-DES ~ tior, ti R h
P•
Curve Number (CN) • OFF

3.0 In
la • B3
S • f 000/CN•t 0 0.151 in
0.75
D `~=4.Z~L'
2
28 in
(P .0.8.8) .
IeIP •
Un8 Psak Dkchar8e (q,~
0.080
(~M~~Type II ralnfa0 1000 am
Dreirlaps area (A,a 0.0118 M`

2-VR POST-0El LOPMFti R ny
P•
Curve Number (CN) • s-

3.5 In
la • SS
6. 1 OOO/CN-70 0.181 in
0.78
D • IPA
2
73 In
(P . 0.8 • S) .
la? .
Unit Peek Disehar8e (q,J
0.03
(assurtdn8 Type II ralnfap
tllshlbWOn) 1000 am
Drainage area (q,J 0.0118 ml`
D°• Q • ~ ~ q° 31.88 efs
70.YR POST-DES LOPL•~' ^• Ir`^-
P•
Curvs Number (CN) . -

8.1 In
la . 53
S • 1000/CN•10 0.181 In
0.78
D • (P. n_z •~l
30 In
x
(P . 0.8' S) •
ie? •
Unit peak Dkeheres (q,J 0.030
~~~lyps II ralnh8 1000 am
D~napa a1OB (~ 0.0118 mi`
D°•C•A"•q" 15.81 efs
C9LGU eT 7HE WEI6NTEp WEIGHTED C~ ~
RV h ru w
WelBhtea CN 57
la ` 0.151

m
NEWHOPEDEVELOPMENT PROPOSED/SS
w- °--~° ETC
LAND U8E AREA (A) CN
FUTURE DEVELOPMENT
AREA 5.07 93.00
(ASSUME 85%IMPERVIOUS)
Tkna of Coneenaason (T,);
Use 0.1 1u
1-YR POST DEVFI OPA A ~
P.
Curve Number (CN) .

3.0 N
le ~ B3
S .1000/CN-10 0.151 In
0.75
O'!f' •S.Z.S1'
225N
(Pf OE•S)
IaR ~
Un8 Peak Dlccharpe (q,J 0.050
(osuminp Typs it nlnfatl
dkbibutlon) 1000 esm
DnMapa eroa (A„J 0.0079 mN
Ov`O •Am• a,
17.86 eh
2-YR POST-DES OPMFti r
P.
Curve Number (CN) .

3.5 h
la . B3
S.1000/CN-1D 0.151 N
0,75
O~fP.n •sl'
2
73 in
(P~0.8•S) .
h1P .
Un0 Psak gscharpe (q,J
0.043
(esauminy Type II ralnhtl
dlcbibudon) 1000 cam
Drainage area py„) O.OOIB ml'
Oa• O' Ae' 4,
21.87 eh
10.YR POST DE~rol OPA FT R I DF
P.
Curve Number (CN) • F

5.1 In
Ia .
S ~ 1000ICN-/0 B3
0.151 h
0.75
4
30h
(P~0.8•S) .
lalP .
Un0 peak Diccharpe (q,J
0.030
(sasuminp iypa II ralnhU
dia0ibutlon) 1000 am
Dnkwpa area {A„J 0.0079 mi`
Or`O'Ae•q„
34,03 eh
A eT THE yyE1pNT~D WEIONTED nn
Wefyhted CN y3
le ~ 0.151

Since all of the drainage azeas are located in the Neuse River watershed and there are
significant slopes on site creating difficult areas to construct level spreaders, constructed
wetlands BMP's have been proposed to control the post development increase run-off
and reduce the runoff nitrogen levels. A constructed wetland has been designed for each
of the three major drainage areas. A summary and calculations for each BMP is listed
below.
Drainage Area `A'
Drainage area `A' was divided up into 3 different sections for this analysis; the area
draining to the proposed basin from the proposed warehouse construction, the area
draining to the basin from the future building area, and the areas that are bypassing the
basin and exiting at the ultimate discharge point. The
the runoff from the impervious surface azea from the lp s orm and. detain t for 2 to Saze
days. This volume was calculated using Schuler's simple method and the results have
been provided below:
/" wA7eR QuA! t7v vet ~ ~~.
Schuelers Simple Method
Post-De~atonm=~t ,
Rv=0.05+0.9•h
where:
I~ =Impervious Fraction 0.73
R„=Runoff Coefficient 0.71
Volumo of Pre-Development
Runoff:
V =3830 • Ro ' Rv • A where:
Ro =Destyn Storm 1.0 to
Rv =Runoff Coett. 0.05
A = Waterehetl Area 14.04 ac
V=
38,032 d
This volume is to be captured by the BMP and detained for 2 to 5 days. A 3" inverted
siphon is proposed to be placed in the outlet structure at the permanent water elevation
and will release the storm water at a maximum flow of 0.24 cfs and will drain the basin in
3.38 days. The routing for this storm can be found below:
-arunn ,~~.
6tatnRl
Stage
(10
7ofalOufllow
71me

~
'~ u32 1 0 (eh1
024 PoNn1 m
~'~ 0.53 021 1800 0.00
~ 902 0.77
0
72 021 38D 0.13
025
2 .
0.67 020
0
19 28 0.35
.655 o.tn .
o 19 7 o.so
~~~ D.s7 o
1a 900 0.63
20,7 0.53 .
0
17 0.75
0.46 .
0
16 1260 oaa
17,097 0.44 .
0
15 1440 1.00
85 .
0
15 80
13,7 0.~ .
0.14 1 125
10,~ D29 0.13 216D 1.50

0'u 0.13
0
12
252
1.63
5,169
e
a7z n
~ .
0.11 ?
0
2700 i.~
,
s,eao 1
9
o.1e o.to
0
09 25eo 2,~
3
098 0.14 .
0.0D ~~ 213
225
.
3,051 0.11
o.oe 0.05
o
07 yt~ 2.35
0.07 .
0
06 3780 250
B34 .
0
05 2
5
1,070 D.03 .
4 3900 7
o.oz o.0
3 4140
4320 2.ea

17 0.01
0
00 o.oz
4599 3.00
3.13
0 .
0.00 0.01
0
00 325
. 4560 3.35

l
The second purpose of this BMP is to detain the storm water form the 10-year storm and
release it so that the 10-year flow rate at the ultimate discharge point will not exceed the
pre-existing conditions. Because of the grading of site, it is impossible to capture all of
the post development runoff in the BMP. Below is the 10-year post development flow
rate that is bypassing the basin and discharging the site at Ultimate Discharge point `A'
calculated using the TR55 method:
NEW NOP ncvei no en, pROP~ED DIRE T R ~
ISTI WEIDHTED CURVE
LAND USE
SEA IA7 CN
BUILDING (gyp)
0.00 88.00
PAVEMENT
0.83 .98.00
GRASS
7.97 65.00
(HSG B b C, WOODS, GRASS COMBO)
TOTAL AREA
8.80
A C 4 THE WEIOHTFO WEICHTE JE NUMnc
WeiBMed CN=SUM (= 0.00 x 98 1 • f 0 83
~f 797x ~rl
8.80
WeIOMed CN = 67
la a 0.985
Tlme o! COngntratlon (T~:
T•= 0.007 •(n•L)°r/p~ed • aa.
when:
Sepmam 1
L = Flow lenOth `

n = manniBna ra+Bhnea coeR. 75 R
0
4
P~:2 year, 24 hour ralnfaa .

a = abpe of hydra8c Brads line 3.S H
0,107 RIR
T`r 0.138 hr
Segment 2
Shoaow Concentrated flew.
T,=L/3600•V
L=flow LanOth =
V = VebcRy = 332 R
a=ab of
pe hydralb grade Ilne 4.2 Rheo

T`~ 0.072 R/R
0.022 hr
Sepmem 3
Open Channel Bow
V=1.49•r~O•erofn
where:
r = Wq•: hydn8e 2dlue

a=lbw area 0.490 R
14 Ra
0.=welled perimeter 28.SBR
a = dgnnN sbpa
0.004 R/R
n = manninBY eaefL 0.022
V=
T•= L! 3800 • V
2.86 Rh
L=
T
`~ 1454 R
Q152 hr
T•r ~ T•~ r T~
0.313 hr
10-VR POCT-D ~ i no
P=
Curve Numher (CN). 5.1 b
la = B7
S = t000rCN-10 0.885 In
4.83
C=~'~"~

(P~0.8•S) 1.01 N
IaIP =
UN[ Paak Dkeharpe (y,)
Q 183
~
Type I) rainfatl
a 620 am
Dn4lape area (A„J 0.0134 mN

15.87 ofa

The direct runoff at the ultimate discharge point was calculated to be 15.87 cfs. Since
the pre-development flow rate was determined to be 31.37 cfs, a discharge rate of 15.50
cfs from the basin must be obtained in order to keep the 10-yeaz flow rate to at or below
the pre-development condition. A 48"x48" concrete riser with a 15" barrel was
selected to control the 10-yeaz flow to the basin. Below are is the 10-year routing for
the basin as well as the stage/storage curve calculation:
BASIN
.EVATION AREA AVp AREq HEIOHT
VOLUM CUMULATII
198.0 40,705 E VOLUME
199.0 42,520 41,313 7.0 41,913 41,313
200.0 u 090 43,755 1.0 43,755 85,068
201.0 47,515 48,251 1.0 48,253 131,320
202.0 50,100 4E.500 1'0 4!•L05 180,126
203.0
52,740 51'420 1.0 51,420 231,546
204.0 FREEBOARD
ORApE E_-

V~+ ` EyAT1pN5

38.032 ci provided a!
~'
2
•
201.0

Vuo•
148,721 ctprovWed at ~
7 198.D
wa.
201.1
$b Q4!/$6DfiQ~
cw,w
200,001
150.00(
a
e
e
~ 100,000
SD,000
0
•,
_._ ...., +.0 4.5 5.0 b.5
~+a• (n(

Formulate 10-vr Des(na H ydm~ ~
Drainage Area
Pre-Development CN 14.04 Ac

Post Development CN 83
89
Q°
QP b aw 31.37 ds

Qpm»a~n»n 64.89 cis

Q •~.+o», aw 15.87
15.49
P=
SCS Curve #
Comoure Tlme to Pe k
TP = Vo111.39 • Qp
1.25 TP
5.1 in (10-yr, 24 hr predp)
89
1.23
3.87 (n
28 min
35
Stage Storage
Ks =
b=
Zo =
2~ _
Zi -Zo =
40,948
1.069
198.0 ft
198.9 ft
0.9 ft
Outlet Centmr
-•°~~~°~~ «ceroco
OnBce size ntrollvrnenn

Area 3 in
0.049 sf
Discharoe RiseNBarret
t4S~ntrol 10-vr flood crr,
Riser Size 48»x48» in
Riser Area 18.000 sf
Riser Length 18-00 ft
Barret Diameter 15 in
Barrel Area 1.227 sf
Results 10-Year Flood Routine
Max. Storage Vol. 146,721 cf
Max. Stage Elev. 3.30 ft
Max Outflow 10 yr 13.00 ds
Flood Rountine Comoutatten: un ..
Time -- -° InBow
S(a ft~ S p9e Totai Outflow 1-Year Riser Riser
(dst n.;ns ..,_. Barrel
3
8 2.40
9.34 p
432 0
0.00 0
0.00 0
0.00
9
12 20.02 2,108 0'01 0.03
0
~ 0.03

15 33.24
47
51 5,702 p,~g '
0.09 0.08
0
09
21 .
B1.19 11,669
20,198 0
52 0.13 .
0.13

24 72.78 31,181 .
0.78 0.17
0
21 0.17
80.88
84.87 44,240
58
124 .
3.78 0.21
0.24
30
33 83.87 ,
71,577 1.39
1
69 9.93 0.28
38 77.99
x
87 84,749 .
1.97 10.46
10.89 0.31
0
33
39 '
59.70 98,810
107,114 2.24
2
48 11.43 .
0.35
42
45 51.90 115,738 .
2,84 11.79
t2
~ 0.37
48 45.12
39.23 122,908
128
812 2.80 '
12,31 0.38
0.39
51
54 x'11 ,
133,822 2.92
3
02 12.50 0.40
57 29.65 137,483 .
3.10 12'~
12
78 0.41
60 25.78
22
41 140,520 3.17 .
12.87 0,42
0
42
63 .
19.48 142,843
144 548 3.22
3
25 12.94 .
0.42
68
69 16.94 145,718 .
3.28 12.99
13
03 0.42

72 14.73
12
80 148,419
3,29 .
13.05 0.43
0
43
75 .
11.13 148,721
148
674 3.30 13.08 .
0.43

76
9.88 ,
148,327 3.30
3
29
13.08
0.43
81 8.41 145,720 .
328 13.05 0.43
87 7.31 144,889 3,26 13.03
13
00 0.43
90 8.38
5.53 143,864
142
873 3.24 .
12.97 0.43
0.42
93
98 4.81 ,
141,340 3.21
3.19 12'~
12
90 0.42

99 4.18
3.63 139,883
138
322
3,15 .
12.85 0.42
0.42
102
105 3.18 ,
138,671 3.12
3
09 12.80 0.42

108 2.75
2
38 134 ~ .
3.05 12.75
12,70 0.41
0
41
. 133,153 3.01 12.84 .
0.41
0.00 0.00 g,7Y
0.00 0.00 8.75
0.00 0.00 6.86
0,00 0.00 7,11
0.00 0.00 7,47
0.00 0.00 7.94
0.00 0.00 8.49
3.51 32.13 9.08
18,34 53.63 9.66
33.44 68.08 10.18
53.48 79.61 10.66
74.13 88.77 11.08
93.34 95.88 11.42
110.42 101.38 11.70
125.25 105.73 11.92
137.89 109.17 12,10
148.45 111,89 12.25
157.09 114.02 12.36
183.89 115.67 12.45
189.33 118.91 12.52
173.28 117.81 12.57
176.00 118.43 12.60
177.84 118.79 12.62
178.35 118.85 12.63
178.24 118.93 12.63
177.43 118.75 12,82
178.01 118.43 12.60
174.07 117.98 12.56
171.69 117.45 12.55
188.94 118.62 12.51
165.87 118.11 12.48
162.53 115.33 12.43
158.99 114.48 12.39
155.28 113.58 12.34
151.39 112.63 12.29
147.41 111.83 12.23

The results from the routing indicate that the 10-year flow from the basin will be 13.06
cfs. By combining that with the flow that is bypassing the basin, 15.87 cfs, a total 10-'
yeaz flow of 28.93 cfs is calculated at Ultimate Dischazge Point `A', which is below the
31.37 cfs pre-development rate.
Drainage Area `B'
Drainage Area `B' is the azea located north of the proposed road and east of the existing
perennial stream. At this time, there is no development proposed for this area.
However, this azea could be developed some day and in order to minimize the
environmental impacts for this entire property, a storm water wetland BMP was sized
for this site assuming the site would be developed at 85% impervious. This azea will
have the same 1" storm and 10-yeaz stone requirements as Drainage Area `A', and the
results are listed below:
1• WATER O iet trv vn~ a •~
Schuelefa Simple Method
Post-Developm
t
en
R„=0.05+0.9•I~
where:
I~=Impervious FrecSon 0.85
R„ =Runoff Coefficient 0.82
Volume of Pre•Deveiopment
Runoff:
V = 3630 • Ro • Rv • A where:
Ro=Design Stortn 10 in
Rv= Runofff Coen 0
05
A =Watershed Area .
7.39 ac
~° 21,883 a
9ASw
EVATION AREq
AVG. AREA
HEIGHT
VOLUME cuMUl.grn
VOLUME
192.0 21,915

193.0
23,605 22,760 1.0 22,760 22,780

194.0
25,880 24,633 1.0 21,833 17,303

195.0
27,170 28,415 7.0 28,415 73,906
196.0 FREEBOARD

Formulate 10-vr Desing Hvdrograo h
Dre~age Area 7.39 Ac Outlet Con 1
Pre-Development CN

Post Development CN 83
Discharge OrKce t

O° 93
12.89 cts
Orifice size o control 1 flood
2.5 in
Op
a9.61 as Area 0.034 sf
Dlscharee Riser/Barrel Struc
to control i0-vrflood re
P
SCS Curve0 5.1 in (10-yr, 24 hr pred
P) ~s~ Stza
RlserArea 48'k48" in

S = (1000/CN) -10 93
Riser Length 18.000 sf

Q' _ (P-0.2S)2/(P+0.8S) 0 75 16 00 ft
4.30 in
Barrel Diameter

Comout~Tlme to pew
Barrel Area
1.2 15 in
27 sf
TP = VoV1.39' Op
28 min
1.25 TP
35
Stage Storage Results 10-Year Flood Routln
Ks = 22 712 Max. Storage Vol. 74
14 8 cf
b = 1.070 Max. Stage Elev. ,
3
02 ft
Z° = Max Outflow 10 yr .

Z' 192.0 ft 12.5 3 cts
193.0 ft
Zr-Z-0=
1.0 ft
Flood Rounting Comgutntr~ r10 v ri
Time
min Inflow
~ Store e
9
S~9e
TotalOutfiow
1-Year
Rise

0
0
Oft
ft
cfs
Orifice r
Weir Riser
Orifice 8arcei

3
1.40
0
0
0.00
0
0
0,00

O Orifice
9 253 0.01 0
02 0.00 g~2
12 1.70 1.232 0.07 .
0
0,1 0.02 0.00 0.00 6.75
19.43 3,330 0.17 . 0.04
0
07 0.00 0.00 6.88
18 27.77 8,816 0.32 0
09 . 0.00 0.00 7.13
21 35.77
42
53 11,797 0.54 .
0.12 0.09
0
12 0.00 0.00 7.51

24 .
47.28 18,213
25
841 0.81
0.15 .
0.15 0.00
0.00 0.00
0
00 7.99

27
30
49.49 ,
33,923 1.13
1.48
2.38
9
97
0.17
2.20 .
27.50 8.56
9.18
48.90
45.58 41,035
47
950 1.74 . 0.20
0.22 14.74
30.47 51.81
60
00 9.78
38
39
40.14 ,
54,184 2.01
2.25 10.95
11
35
0.23
48.80 .
77.23 10.27
10.72
42 34.89
30
34 59,385 2.48 .
11.67 0.25
28
0 67.45 88.02 11.11
45 .
28,37 63,545
66
859 2.62 11.92 .
0.28 84.30
98.69 92.66
97
66 11.42
48
51
x•93 ,
89,425 2.74
2.84 12.12
12
27
0.27
110.58 .
101.43 11.136
11.85
54 19.93 71,344 2.92 .
12
37 0.28 120.06 104.25 11.99
57 17.33
15 72,705 2.97 .
12.45 0.28
0
28 127.31 108,31 12.08
.07 73,583 3.00 . 132.52 107.74 12.17
83 13.10 74,045 3.02 12.53 0.28
0
28 135.92 108.65 12.22
11.39 74,146 3.02
12
53 . 137.72 109.13 12.24
66 9.90
73,942
3.02 .
12
52 0.28 138.12 109.24 12.25
69 8.81 73,470
3.00 .
12
49 0.28 137.32 109.02 12.24
72

75
7.48
72,770
2.97 ,

12
45 0.28 135.48 108.54
12.21

78 8.50
5
88 71,875 .
12.40 0.28
0
28 132.78 107.87 12.17

B1 .
4.92 70,813
88
609 2.90
12.34 .
0.28 129.34
125.29 106.67
105
74 12.12

84
87
4.27 ,
88,284 2.85
2.80
12.28
12
20
0.28
120.75 .
104.45 12.07
12.00

90 3.72
3
23 88,858 2.74 .
12.12 0.27
0
27 115.82 103,01 11.93
.
2.81 85,348
63
782 2.69 .
0.27 110.58
105,10 101.43
99
73 11.85

99
2•~ ,
82,119 2.83
2.58 11.94
11
84
0.27
99.46 .
97.91 11.78
11.87
102 2'12
1
85 80,428 2.50 .
11.74 0.28
0
28 93.70 95.98 11.58
.
1.130 58,898
58
938 11.63 .
0.28 87.89
82.06 93.98
91
83
108
1.39 ,
55,151 2.36
2.29 11.52
11
41
0.25
76.28 .
89.61 11.38
11.27
. 0.25 70.51 87.30 11.18
e

Drainage Area `C'
Drainage Area `C' is the area located south of the proposed road and east of the
existing perennial stream, It is in the exact same situation as Drainage Area `B' in that
there is no proposed development at this time, but it may be developed in the future and
storm water BMP will be necessary. Below are the calculations for sizing the BMP for
this drainage area:
1" WATER QUALITY VOl IIAIIF
Schueler's Simple Method
Po t-D ~~looment
R„=0.05+0.9•I~
where:
IA =Impervious Fraction
R,=Runoff Coeffidant 0.85
0.82
Volume of pre-Development
Runoff:
V = 3630' Ro • Rv • A where:
Ro =Design Storm 1.0 in
Rv = Runoff Coeff. 0.05
A =Watershed Area
V = 5.07 ac
1a,sss a
BAS1N
EVATION
198.0 AREA
18,160 AVG. AREA HEIGHT
VOLUME CUMULATn
VOLUME
199.0
17,570 18,865
1'0 18,885
18,885
200.0 19,040 18,305 1.0 18,305 35,170
201.0 20,580 19,800 1.0 19,800 54,970
Shp~lStonp~
b0,Oq
~400f
ao,ooa
0
20,000
ioaoo
0
mn
-- :.o s.o
~~ tnt a.s

~a
Formulate l0-vrDesin vdroareoh
Drainage Area 5.07 Ac
Pre-Development CN 8S
Post Development CN 93 .
Q0 8.84 da
0D 34.03 ds
P=
SCS Curve # 5.1 in (10.yr, 24 hr predp)

S = (1000/CN) - 10 93
0.75
0' _ (P-0.2S)2/(P+O.BS) 4.30 in
Compute Time to Peak
Tp = VoU1.39 • Qp
28 min
1.25 TP 35
Stsce 5+~~=
~
= 16,822
_
b 1.074
_
Z0 198.0 ft
Zr 199.3 ft
2~-Zo - 1.3 ft
Flood Rount(nc Comoutatlons f10 vrl
Time Inflow Store e
i...~..~ _ . 9
Outlet Control
Orifice size 2 loin
Araa
Dlsdt 0.022 sf
aroa Riser/Bar
20 control 10-vr flood
Riser Size rel t ire

48"x48" in
Riser Area 18.000 sf
Riser Length 16.00 k
Barrel Diameter 12 In
Barrel Area 0.785 sf
Results 10-Year Flood Routlna
Max. Storage Vol. 53,467 d
Max, Stage Elev. 2.94 ft
Max Outflow 10 yr 7.94 ds
Total Outflow 1-Year Riser Riser
/K..\ .-
3
6 0.98
0 "
0.00 0
0.00 0
0
00 0.00 0

9
3.74
173
0.01
D.01 .
0
01 0.00 0.00

12
8.03
13.33
845

2
288
0.08

0.03 .

0.03 0.00

0.00
0.00
0
00

15
19.05 ,
4,877 0.18
0
30 0.04 0.04 0.00 ,
0.00
18 24.54
8,098 .
0.51 0.06
0
07 0.08 0.00 0,00
21
24
29.18
12,499
0.7B .
0.09 0.07
0
09 0.00 0.00

27
32.44
17,734
1.05

0.11 .

0
11 0.00 0.00

30 33.95

33.55
23,553

29
489
1.37

0.98 .

0,12 0.00

0.85 0,00

20
04
33 31.27 ,
34 ~0 1.69
1.94 6•~
8
93 0.14 11.54 .
47.75
38
39 27.54 38,711
2.17 .
7
18 0.15 24.75 61.59

42
23.94
42,375
2.38
.
7.38 0.15
0
18 39.15 71.76

45
20.81
45,357
2.52
7.53 .

0
17 52.67 79.22

48 18.09
15.73 47,747
49
828 2,84 7.65 .
0.17 64.55
74.60 84.77
88
96
51 13.88 ,
51,062 2.74
2.81 7.75
7
82 0.17 82.81 .
92.11

54
11.89
52,118
2.87 .

7
87 0.18 89.28 94.44
57 10.34
52,839
2.90 .
7
91 0.18 94.08 96.11
60
63
8.99
53,276
2.93 .
7.93 0.18
0
18 97.43 97.24

68
7.61
8
79
53,487
2.94 .

0.18 99.48

100.37 97.92

96
21
69 .
5
90 53,444 2.93 7.94 0.18 100,27 .
98
18

72 .
5,13 53,236
52
874 2.92 7.93 0.18 99.30 .
97.86

75

4.48 ,

52,374 2,90

2
88
7.91
0.18
97.80
97.30

78
3.88
51,759 .
2.85 7.88

7
85 0.1 B 95.27 96.52
81
84 3.37
51,043
2.Si .
7.82 0.18
0
18 92.43 95.55

87
2.93
2.55
50,243
49
370
2.77
7.78 .
0.17 89.17
85.58 94.41
93
12

90
2.22 ,
46,438 2.73
2.68
7.74
7
89
0.17
81.87 .
91.89
93
96 1.93
47,451
2.83 .
7.84 0.17
0
17 77.58 90.13

99
1.68
1.48
48,423
45
359
2.57
7.59 .
0.17 73.33
68.98 88.45
86
87

102
1.27 ,
44,265 2,52
2.48
7'~
7
~
0.17
84.58 .
84.78
105
108 1.10
~ 43,147
2.40 •
7.42 0.18
0
18 60.12 82.78

0.98
42,010
2.34
7
38 . 55.67 80.89
. 0.18 51.27 78.51
Barrel
4.30
4.32
4.40
4.55
4.77
5.07
5.41
5.78
6.18
8.52
6.79
7.03
7.22
7.37
7.46
7.56
7.64
7.69
7.73
7.75
7.76
7.76
7.75
7.73
7.71
7.68
7.64
7.61
7.58
7.52
7.47
7.42
7.37
7.31
7.26
7.20

,. ~ r i-v 117 Centrewest Court
.~ 1 V L Engineering, Inc. Cary, NC 27513-2015
C(vt(Bngtpgdy ~e coxdsurveyos Phone: [phone]
Faz: 919-677-1998
New Hope Development -Storm Water Analysis
Apri18, 2008
Conclusion
After analyzing the pre-development discharge and the post-development discharge
from the site, it was determined that a BMP device is necessary to treat storm water
generated by the proposed and future developments. Storm water wetlands were
selected since they provide the most pollution reduction of any BMP. At this time, only
the BMP for Drainage Area A is to be constructed in order to detain and treat the
proposed warehouse runoff. The other two BMP's will be properly sized and
constructed with any future development. Please see the following page for a complete
results table from this storm water analysis.

i
Pond 1
Weir Outlet Box Anti-Flotation Calculations
Project Name: New Hope Development
Project Number: 07-579
Designer: TRS
Pond Number /Description: Pond #1 Perm. Outlet Device
Date: 4!3/2008
Box Front Internal Dimension = 4.0 feet
Box Side Internal Dimension = 4.0 feet
Box Wall Thickness = 0.5 feet
Box Bottom Thickness = 0.5 feet
Box Top Thickness = 0.0 feet
Height of Box, interhal dimension = 4.80 feet
Outside Diameter of barrel(s) exiting box = 31.0 inches
Number of barrels exiting box = 1
Diameter of DIP drain pipe entering box = 3.0 inches
Diameter of manhole opening in top of box = 0.00 feet
Total Flow Opening Area in sides of box = 0
00 SF
Temporary CMP Pipe Diameter (if present) = .
0 inches
Amount of Concrete present in Standard Box defined a#~eva
Concrete present in box no adjustments for oaeninas >
Total Volume present in top = 0.000 CF
Total Volume present in front = 12.000 CF
Total Volume present in rear = 12.000 CF
Total Volume present in RH side = 9.600 CF
Total Volume present in LH side = 9.600 CF
Total Volume present in bottom = 12.500 CF
Total Concrete Present, no adjustments = 55.700 CF
Adfust total concrete aresent for ooeninas -->
Subtract for perm. barrel opening = 2.621 CF
Subtract for manhole opening in top = 0.000 CF
Subtract for drain pipe opening in front = 0.025 CF
Subtract for flow openings, front and side = 0
000 CF
Subtract for temp. CMP pipe opening, if present = .
0.000 CF
Total Adjustment Volume = 2.645 CF
Therefore, focal concrete present In box = 53.055 CF
Page 1

Pond 1
Total Water Disolaced by Qutiet Str~ct~re
Water displaced by concrete in box = 53.055 CF
Water displaced by air inside box = 76.800 CF
Total Water displaced = 129.855 CF
Weight of total water displaced (@ 62.4 PCF) = 8103 lbs.
For a safety factor of 20%, the weight of concrete that must be present = 9724 lbs.
Total weight of concrete present (@ 150 PCF) = 7958 lbs.
Therefore, must add a total of 1765 lbs. of concrete
Buoyant weight of concrete, with 20% safety factor included = 73.00 PCF
Therefore, need to add 24.18 CF of concrete to base of outlet structure
Standard outlet structure base is =_> 0.50 feet thick
25.00 SF (plan dimension)
Concrete present in standard outlet structure base = 12.50 CF
Therefore, total concrete present in newly designed base must = 36.68 CF
Design of new base for o~ i t str~ct~re
Concrete required = 36.68 CF
New base dimensions =_>
8.00 feet long
8.00 feet wide
24.00 inches thick
Total Concrete present in new base design = 128.00 CF OK
Check validity of new base desain ~s to flotation characteristics
Total concrete present in final design = 168.555 CF
Total water displaced in final design = 245.355 CF
Total weight of concrete present in final design = 25283 lbs.
Total weight of water present in final design = 15310 lbs.
Actual safety factor present in final design = 1.65 OK
=final Base Deslgn =_>
8.00 Width
8.00 Length
24.00 Thickness
Page 2

New Hope Development
STORM WATER REPORT
SeCt1011 2
Storm Drainage Calculations

10-Year stom Daaign
FROM TO DVCAB- EQUIV. TOTAL T 1 Q-CIA CAPAC• DIAM. LENGTN SLOPE MIN HG NG FOR ACTUAL VE4 TIME H.G. H.G. GROUND ELEV. INVERT ELEV.
MH MH MEN7 C AREA AREA TIME (IN C.FS. ITYOF OF OF OF BASED 2S FPS HG FLOW OF ELEV. ELEV. UPPER LOWER UPPER LOWER
' INPUT ACRES 100X 100X (MIN.) PER FLOW SEWER PIPE LINE PIPE ON "Q" GIVEN "D" (X) FULL FLOW UPPER LOWER END END END END
(A) ACRES ACRES HOUR) (C.FS.) (IN.) (FI'.) (X) ~(%) (%) (FI'J (MIN.) END END
CA SUM CA SEC.) '

STUB A 7 0.25 0.77 0.19 0.19 5.00 7.22 1.39 7.00 l3 203 1.00 0.04 0,23 1.00. 5.7 0.6 213.28 213.23 220.00 218.40 214.28 212.23
7 6 0.72 0.77 0.55 0.75 5.60 7.07 5.28 5.42 i5 92 0.60 057 0.23 0.60 4.4 0,3 213.25 212.70 218.40 216.80 212.25 2] 1.70
6 S 0.19 0.77 O.1S 0.89 5.90 6.99 6.24 6.26 15 135 0.80 0.80 0.23 0.80 S.l 0.4 21270 211.62 216.80 219.00 211.70 210.62
S 4 0.18 0.77 0.14 1.03 6.30 6.89 7.1! f.05 IE 44 0.50 0.40 0.16 0.50 4.6 0.2 211.62 21].40 219.00 217.00 210.42 210.20
4 3 0.36 0.77 0.28 1.31 6.30 6.84 i.96 9.32 IB ISO 0.70 0.63 0.18 0.70 5.4 0.5 211.40 210.35 217.00 217.00 210.20 209.15
3 2 0.69 0.77 0.33 1.84 7.00 6.72 1237 13.42 24 265 0.30 0.26 0.12 0.30 4.3 1.0 210.35 209.55 217.00 217.00 208.75 207.95
2 1 4.84 0.77 3.73 3.37 8.00 6.50 36.19 39.58 36 86 0.30 0.26 0.07 0.30 5.6 0.3 203.65 203.39 217.00 216.80 198.75 198.50
1 C 0.00 0.77 0.00 5.37 d30 6.44 36.19 39.38 36 161 0.30 0.25 0.07 0.30 5.6 0.5 203.39 20290 21i.i0 FS 198.50 198.00

8 6 0.04 0.77 0.03 0.03 5.00 7.22 0.22 6.64 1S 58 0,90 0.00 0.23 0.90 5.4 0,2 213.22 212.70 216.70 216.80 21226 211.74

' STUB B 2 4.15 0,T1 3.20 3.20 5.00 7.22 23.0E ]A.51 24 29 1.00 0.90 0.12 1.00 7.8 0.1 203.94 203.65 21200 217.50 200.04 199.15

C06 11 0.69 0.77 0.53 0.53 5.00 7.22 3.84 9.90 IS 51 200 030 0.23 200 B.I O.I 217.56 216.56 22).60 220.00 216.3E 215.56
11 CDS 0.09 0.77 0.07 0.60 5.10 7.20 432 4.95 15 30 0.30 0.39 0.23 0.50 4.0 0.2. 216.56 21631 220.00 221.00 215.56 213.31
COS COI 0.69 0.71 0.53 1.13 3.30 7.14 E.09 8.i1 IE 100 0.60 0.51 0.18 0.60 5.0 0.3 21631 215.71 221.00 221.00 215.11 214,51
C04 10 0.69 0.77 0.53 1.66 5.60 7.07 11.75 11.93 IB SO 1.10 1.08 0.18 1.10 6.E 0,1 215.71 215.16 221.00 ZZ0.00 214.51 213.96
10 C03 0,09 0,77 0.07 1.73 3.70 7.01 12.20 17.33 21 Si 0.50 0.25 0.12 0.50 5.3 0.2 215.16 214.91 220.00 221.00 213.36 213.31
C03 C02 0.69 0.77 0,53 226 3.90 6.99 15.82 17.33 24 100 0.50 0.42 O.i2 0.50 S.S 0.3 214.91 214.41 221.00 221.00 213.31 212E1
C02 COI 0.69 0.77 0.53 2.80 6.20 6,91 19.33 20.50 .24 100 0.70 0.63 0.12 0.70 6.5 0.3 214.41 213.71 221.00 220.70 21281 21211
COl 9 0.69 0.77 0.53 3.33 6.50 6.84 2276 24.31 24 70 1.00 0.87 0.12 1.00 7.8 0.1 213.71 213.01 220.70 219.80 21211 211.41
9 D 0.10 0.77 0.08 3,40 6.60 6.t2 23.21 24.34 30 104 030 0.28 0.09 0.28 S.D 0.3 203.19 20290 219.E0 ES 198.32 198.00

Culvert Analysis Summary
ANC analyzed the major culvert crossing by using TR 55 for the hydrology and
HY8 for the culvert analysis by looking at the 10 year storm and the 100 year
storm for overtopping.
The drainage area is 57 acres and of which the majority of the drainage area is
commercial zoning with some open space areas and about 17 acres of
undeveloped property which will be subject to Raleigh Stormwater regulations
should development occur in the future.
By using a 5' (60") culvert the 100 year headwater does not exceed the 15'
maximum and the 10 year storm exceeds the required 2' freeboard as noted
below.
Q10=211 cfs
Q100 = 337 cfs
60" RCP
Invert Up = 198.92
Invert Down = 195.78
L=96'
Roadway Elevation = 214:3
10 Year Water surface elevation = 206.75
100 Year Water surface elevation = 213.90

BAR New Hope 1
Culvert 1
Wake County, North Carolina
Sub-Area Time of Concentration Details
Sub-Area Flow Mannings's End Wetted
Identifier/ Len th
g Slo e
P n
Area Perimeter
Velocity Travel
Time

------------- (ft)
------- (ft/ft)
----------
-------------
(sq-ft) (ft) (ft/sec) (hr)
DA 1 to cu
---------------
-----------
-------
SHEET 99 0.0200 0.400

SHALLOW
900
0.0600
0.050 0.335

CHANNEL
1700
0.0235
0.030
12.50 10.00
8.910 0.063
0.053
Time of Concentration .951
WinTR-55, Version 1.00.08 Page 1 4/5/2008 4:99:11 PM

1 ~
BAR New Hope 1
Culvert 1
Wake County, North Carolina
Sub-Area Land Use and Curve Number Details
Sub-Area Hydrologic Sub-Area Curve
Identifier Land Use Soil Area Number
Group (ac)
-------------------------------------------B-
----------------------
DA 1 to cuIndustrial 57 88
Total Area / Weighted Curve Number 57 88
WinTR-55, Version 1.00.08 Page 1
4/5/2008 4:49:11 PM

BAR New Hope 1
Culvert 1
Wake County, North Carolina
Storm Data
Rainfall Depth by Rainfall Return Period
2-Yr
(in) 5-Yr
(in) 10-Yr 25-Yr 50-Yr 100-Yr
1-Yr
---- (in)
----------- (in)
--------- (in) (in) (in)
3.6

.0

5.38 ---

6.91 -----
-------
.0
----8-0-----
----3-0-
Storm Data Source: User-provided custom storm data
Rainfall Distribution Type: Type II
Dimensionless Unit Hydrograph: <standard>
WinTR-55, Version 1.00.08 Page 1 4/5/2008 4:99:11 PM
ti

BAR New Hope 1
Culvert 1
Wake County, North Carolina
Hydrograph Peak/Peak Time Table
Sub-Area Peak Flow and Peak Time (hr) by Rainfall Return Period
or Reach 10-Yr 100-Yr
Identifier (cfs) (cfs)
(hr) (hr)
---------------------------------
--------------------
-----------------
BAREAS
DA 1 to cu 211.63 337.80
12.19 12.14
REACHES
OUTLET 211.63 337.80
WinTR-55, Version 1.00.08 Page 1 4/5/2008 9:47:12 PM
a

HY-8 Culvert Analysis Report

~~~~ "~
1~`CR~ ~
Table 1 -Summary of Culvert Flows at Cirossina• Nr~w Nn.,o r_...,~e:.,~
Headwater Elevation
({t) Total Discharge (cfs) Culvert 1 Discharge
(~) Roadway Discharge
(c~) Iterations
206.29 200.00 200.00 0.00 1
206.75 211.00 211.00 0.00 1
207.48 227.40 227.40 0.00 1
208.13 241.10 241.10 0.00 1
208.83 254.80 254.80 0.00 1
209.58 268.50 268.50 0.00 1
210.36 282.20 282.20 0.00 1
211.19 295.90 295.90 0.00 1
212.05 309.60 309.60 0.00 1
212.96 323.30 323.30 0.00 1
213.90 337.00 337.00 0.00 1

Rating Curve Piot for Crossing: New Hope Crossing 1
214
213
rt
~ 212
O
211
d
w 210
~ 209
= 208'
207'
206-
Total Rating curve
Crossing: New Hope Crossing
----------------c---------
-;-
~ 1 ~ ~ ~ ~------------ --------~-
~ ~ 1 1
' , 1
~ ~ -------~----------j----------J----
~ ~ ~ ~ ~ i
~ ~
_ ~ ;
~ r--..._.__.
r-^--------,'----------~
i ~ ~ , ~ r-_•-____-_~_,
= i ; ~ ~ ~ ~
~ ~ ~
~ ~ ~ ~
~ ~ ' ~ ~ ~ ~
•__________-r-____--_-_.-.
~ ~
~ ~ ~ ~
~ ~ ~ ~ ~
~ ~ ~
i ~ ~ ~
i!!
_--7----•-- i_-_---•--- i--- ~ ~ ~
--_---•-r---•---_--i--•--
~ ~ ~ ----•~_---_------i'------_--'
~ ~ i-
~ ' i ~ ~
: ~ ~ ~ ~ ~ ~
a--:--G--~-a--:--+--G--~-- :--a--a--~--'
-r~
--~--I ~ f• 4 I--;--a--i--~--~ --~--~--~
Total Discharge tcfs~

,,
Table 2 -Culvert Summary Table: Culvert 1
Total Culvert Headwater Inlet Control Outlel Flow Normal
Discharge Discharge Elevation (ft) Depth (it) Control Type Depth (ft)
(cfs) (cfs) Depth (fl)
211.00
C
De
riUcal
pth (ft)

.029
.111 uUet Depth
(ft)

2.659
2.747 Taihvater
Depth (ft)

2.258
2.309 Outlet
VeloGty
(ft/s)
18.852
19.101 Tailwater
Velocity
(fUS)
10.096
10.233
•234
.336 2.874
2.980 2.363
2.442 19.479
19.780 10.432
10,584
.438 3.087 2.500 20.038 10.731
.540 3.190 2.555 20.330 10,876
,643 3.282 2.808 20.687 11.011
.745 3.371 2.860 21.037 11.146
.847 3.457 2.710 21.387 11.274
949 3.539 2.780 21.748 11.397
000 3.639 2.808 22.054 11.515

.,
.-
Culvert Performance Curve Plot: Culvert 1
Performance curve
Culvert: Culvert 1
Inlet Control Elev Outlet Control Elev
214
------ ,
~ ~ ' r---'_-__--*-----_____
' ~ ~ ~ ~
' ~ ~ ~ , ~
X212 '
----------}----------i----------J--- ' ~
' ~ ~ ~ ;
0210 - ~ ,
1 ;
> 2os ---T------ ~
- ,
w ~ ~ ;
206 '
L -- -----•-•-~-•---•-----'--•---•-- - ~
' i ~ --~--•-•-~---;----------~-----------~----•-t
~ 1---~ -
r
~ 204 -------------;-----------;-----------~-------~-~----------;--------- '
a~i 202 ---:- --; ----~-----i -
'
200 ---=---------- ~----------=
~ ~ --------i-~-------~----------.-•
, ~ ~ ,
' ~ ~r- -- ~ -.~
' I I I
Total Discharge (cfs)

~, ,
Water Surface Profile Plot for Culvert: Culvert 1
Crossing - Nevv Hope Crossing 1, Design Discharge - 211.0 cfs
Culvert -Culvert 1, Culvert Discharge - 211.Q cfs
215 -----;----------,------------
~.~_
- ,
210 ----------------~------- ~--
~ ~ '
+- - -~ ;
c - ~ ~ ~ '
o : ~ ~ ~ -
•~ 205 - ~ ~ ,
r ---------r---------' ' '
~ ~_--.--____T-________-r__- -_-_- ;_---
`' ~ i ' ~ ~ --__--i-_-
~ ~ ~ ~ ~ i
~ ~
~ ~
i ~ 1 ~.. ~ ~
~~ ~ ~ ~
200 ---------------- --------- ;---------~~`."f '- .~~ -~-; ,
~ ~ ~ ~
~ ~ ~ ~
~ ~ ~ ~ :
~ ~ ~ ~ ~
~ ~ ~ ~
~ ~ ~ ~ ~ ~
~ ~ ~ ~ ~ ~
195 _'
- --f---- -- -N-- -- -- ~ 1
'emu u ~u 40 60 80 100 1
Station (ft~
Site Data -Culvert 1
Site Data Option: Culvert Invert Data
Inlet Station: 0.00 ft
Inlet Elevation: 198.92 ft
Outlet Station: 96.00 ft
Outlet Elevation: 195.78 ft
Number of Barrels: 1
Culvert Data Summary -Culvert 1
Barrel Shape: Circular
Barrel Diameter: 5.00 ft
Barrel Material: Concrete
Barrel Manning's n: 0.0120
Inlet Type: Conventional
Inlet Edge Condition: Square Edge with Headwall
Inlet Depression: None

•
Table 3 -Dow nstream Cha nnel Rating Curve (Crossin g: New Hope Cros
i
1

Flow (cfs)
Water Surface
Depth (ft)
Velocity (ft/s)
Shear (psf) s
ng
)
Froude Numb

Elev (tt) er
200.00 198.06 2.26 10.10 4.51
1
58
211.00 198.11 2.31 10.23 4.61 .
1
58
227.40 198.18 2.38 10.43 4.76 .
1
59
241.10 198.24 2.44 10.58 4.88 .
1
59
254.80 198.30 2.50 10.73 4.99 .
1
60
268.50. 198.35 2.55 10.88 5.10 .
1
61
282.20 198.41 2.61 11.01 5.21 .
1
61
295.90 198.46 2.66 11.15 5.31 .
1
62
309.60 198.51 2.71 11.27 5.41 .
1
62
323.30 198.56 2.76 11.40 5.51 .
1
62
337.00 198.61 2.81 11.51 5.61 .
1.63

~ ~ 9
Tailwater Channel Data -New Hope Crossing 1
Tailwater Channel Option: Trapezoidal Channel
Bottom Width: 2.00 ft
Side Slope (H:V): 3.00 L:1)
Channel Slope: 0.0320
Channel Manning's n: 0.0300
Channel Invert Elevation: 195.80 ft
Roadway Data for Crossing: New Hope Crossing 1
Roadway Profile Shape: Constant Roadway Elevation
Crest Length: 100.00 ft
Crest Elevation: 214.34 ft
Roadway SurFace: Paved
Roadway Top Width: 40.00 ft