SW3230701_Stormwater Report_20240223

HT STORMWATER MANAGEMENT REPORT
FOR:
THOMAS
HUTTON
STEWART'S GROVE SUBDIVISION
WINGATE, NC
PREPARED FOR:
SOUTHBURY DEVELOPMENT, LLC
31540.0000
FEBRUARY 2024
,„11t11ir,,i
`moo . LESS/O• -L ````ttttA CARr/l��14
O % �\ C �i
::-"ioiJ9 �`_�.• THOMAS. .. �S
•
$ HUTTON
i� •'• GIP1ESq-•'• ENGICEOERING
;9�,� .. ..•.
'�i T.MCF 0���•` S. No. F-0871 _'moo
thomasondhutton.com

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
STORMWATER MANAGEMENT REPORT
Stewart's Grove Subdivision
Project: Stewart's Grove Subdivision
T&H Job Number: J-31540.0000
Location: Between Stewart Street, Witmore Road, and Lefsey Drive
Wingate, NC 28174
Parcel ID: 09-060-002, 09-025-033
Date Prepared: February 2024
Owner: Southbury Development, LLC
Address: S Main St
Wingate, NC 28174
Engineer: Thomas & Hutton
Address: 1020 Euclid Avenue
Charlotte, NC 28203
Phone: [phone]
H THOMAS & HUTTON
Page 1

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
TABLE OF CONTENTS
Section 1 -Summary of Results Page 3
Section 2- Project Narrative Page 3
Section 3- Purpose Page 4
Section 4- Regulatory Summary Page 4
Section 5- Methodology Page 5
Section 6- Hydrology Page 6
Section 7- Runoff Calculations Page 6
Section 8- Existing Conditions Page 7
Section 9- Post Development Conditions Page 8
TABLES
Comparison of Pre- and Post-Development Total Runoff Rates (cfs) 1
Sand Filter/Dry Pond SCM 01 2
Sand Filter/Dry Pond SCM 02 3
FIGURES
Site Location Map 1
Topographic Map 2
FEMA Map 3
Pre-Development Drainage Map 4
Post-Development Drainage Map 5
APPENDICES
Hydrologic Soils Report A
Existing Conditions SSA Reports B
Proposed Conditions SSA Reports C
Sand Filter Design Worksheet D
Riprap Outlet Protection E
Spillway Calculations F
HEC-22 Report G
H THOMAS & HUTTON
Page 2

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
SECTION 1 - SUMMARY OF RESULTS
Table 1 -Comparison of Pre- and Post-Development Total Runoff Rates (cfs)
Storm Event Pre-Development Post-Development DIFFERENCE
2-year 37.31 36.79 -0.52
10-Year 72.80 69.46 -3.34
25-Year 96.12 93.68 -2.44
SECTION 2 - PROJECT NARRATIVE
Stewart's Grove is a proposed residential development within Wingate, North Carolina. This
development consists of approximately 38 single family detached units. The site is located in
Union County at the end of South Stewart Street, east of Lefsey Drive, and west of South Main
Street.
While the majority of the site is currently wooded with an understory of brush, the northmost
section of the site contains about a 3-acre grass field with an existing pond, and there is also
about a 2.75-acre area at the eastmost end of the site that contains a grass field with light tree
coverage. Almost the entirety of the site naturally drains from northwest to southeast, and pre-
development run-off is discharged to Rays Fork, an existing tributary to Richardson Creek. There
are two additional existing ponds that are located offsite but at least partially within the pre-
development drainage basins. The pre-development drainage basins are delineated and
illustrated in the Pre-Development Drainage Map found at the end of this report.
For the purpose of this report, we will compare the pre-development runoff rates to the post-
development runoff rates as shown in the Section 1 summary above. The pre-development
basins SUB-01 and SUB-03 will flow Southwest and outfall into the existing tributary to Richardson
Creek, Rays Fork. The area of these subbasins that is affected by construction will be routed
through one of two Stormwater Control Measures (SCMs) and outfall into the existing Ray's Fork
tributary. Each of these SCMs (Pond-01 and Pond-02) consists of a dry pond with a closed-
bottom sand filter. Basin SUB-02 will outflow to the Northeast woodlands both before and after
development and the area will remain nearly unaffected.
The post-development sub-basins are delineated and illustrated in the Post-Development
Drainage Map found at the end of this report. All design information for the closed bottom sand
filter, dry ponds, and associated drainage pipes and structures can be found in the appendices
of this report.
The soils within these sub-basins consist of type B, C, D, and B/D hydrologic soil groups which are
shown on the attached National Resources Conservation Service (NRCS) soils map within
Appendix A.
H THOMAS & HUTTON
Page 3

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
SECTION 3 - PURPOSE
The purposes of this report are:
1. To delineate all pre-development basins that are within this project and determine
which drainage basins will be affected by the proposed development.
2. To develop a stormwater model that will:
a. Be in compliance with the North Carolina Department of Environmental
Quality.
b. Simulate the pre- and post-development conditions for the project.
c. Predict water elevations for all proposed ponds during different storm events
d. Provide design flows (under future build out conditions) for the major drainage
structures that can be used to properly size improvements, if needed.
e. Provide sand filter design in accordance with NCDEQ Stormwater Design
Manual C-6
3. To document that the stormwater management measures and equipment installed
on site will be adequate for all existing and proposed development on the site.
Two drainage models are included in this report.
• Pre-Development: examines the drainage basin prior to any development within the site.
• Post-Development: examines the drainage basin after site improvements have been
installed. The model may need to be revised and updated as the site plan evolves.
SECTION 4 - REGULATORY SUMMARY
North Carolina Department of Environmental Quality-Stormwater
The North Carolina Department of Environmental Quality (NC DEQ) is responsible for
administering the storm water management program.
Development or re-development activities are required to apply for and receive a stormwater
permit from the NC DEQ. These permits address water quality and quantity.
NC DEQ regulations require that peak post-development discharge rates from the basin shall be
at or below pre-development rates for the 2, 10, and 25-year 24-hour storm events. The
regulations also specify the 1-inch storm runoff volume treatment drawdown time shall be
greater than 48 hours and less than 120 hours to achieve optimal efficiency for channel
protection control. See attached Appendix C for post-development peak flow control
calculations, Appendix D for water quality calculations, and Appendix E for riprap outlet
protection calculations.
H THOMAS & HUTTON
Page 4

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
SECTION 5 - METHODOLOGY
The pre- and post-development conditions of the site were analyzed using the Storm and
Sanitary Analysis (SSA) program developed by Autodesk. The program is used to model rainfall
and stormwater runoff and to perform hydraulic routing through the storm drainage system
(including existing and proposed storage/detention features such as wetlands, ponds, and
lakes).
SSA is an advanced, powerful, and comprehensive modeling package for analyzing and
designing drainage systems, stormwater sewers, and sanitary sewers. The software can
simultaneously model complex hydrology, hydraulics, and water quality. The SSA program is built
on the highly tested and widely utilized SWMM methodologies. For this application of the SSA
program, the hydrology was simulated using the NRCS (SCS) TR-55 methodology. The hydraulics
were simulated utilizing hydrodynamic routing. Hydrodynamic routing solves the complete Saint-
Venant equations throughout the drainage network and includes modeling of backwater
effects, flow reversal, surcharging, looped connections, pressure flow, tidal outfalls, and inter-
connected ponds.
The SSA program graphical user interface (GUI) allows for the input of hydrologic data for each
drainage sub-basin. See the appendices for input variables including runoff curve number,
rainfall distribution pattern, hydrograph peaking factor, area of each drainage sub-basin, and
time of concentration. The SSA program generates runoff hydrographs for each sub-basin based
on these user-specified variables. Hydrographs are generated by SSA using the NRCS Unit
Hydrograph (TR-55) Method.
The model's hydraulic input data consists of a system of nodes and links. Nodes represent
locations where flows enter or exit the system, pipe or channel characteristics change, or where
stage/storage/time relationships are provided. Links represent traditional types of hydraulic
conveyance such as pipes, channels, control structures, weirs, etc. The sizes, inverts, lengths, and
Manning "n" values for all pipes connecting the ponds or lakes are input into the model. In
addition to pipe information, all pond, lake, and detention area stage-area information and the
respective control structure information is input into the model. The node and link conditions are
analyzed within the model for a given storm, and flow conditions are determined.
Hydrographs for each drainage area are merged within the SSA program, and the hydrologic
results are then combined with the hydraulic information to model the hydraulic interactions of
the entire drainage system. The results include pond area and discharge rates and stage/storage
information during the storm events.
The storm drainage infrastructure onsite was modeled using HEC-22 functionality within Civil 3D. This
program utilizes the model rainfall and stormwater runoff through the storm drainage infrastructure
to provide hydraulic grade line calculations and profiles for analyzing the proposed storm drain
network.These computations can be found in Appendix G.
H THOMAS & HUTTON
Page 5

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
SECTION 6 - HYDROLOGY
• SCS TR-55 Method was used.
• The rainfall intensity used for each storm event was obtained from National Oceanic and
Atmospheric Administration (NOAA) Atlas 14. The following design storms are used in the
model simulations:
- 2-year, 24-hour Design Storm = 3.64 inches
- 10-year, 24-hour Design Storm = 5.33 inches
- 25-year, 24-hour Design Storm = 6.37 inches
• SCS Type II Statistical Rainfall Distribution was used. This distribution pattern is determined
by the Soil Conservation Service comparing regional rain-gage data.
• Soils present within the drainage basins consist of the following:
- Badin Channery Silty Clay Loam, 2 to 8 percent slopes (BdB2) - HSG C
- Badin Channery Silty Clay Loam, 8 to 15 percent slopes (BdC2) - HSG C
- Chewacla Silt Loam, 0 to 2 percent slopes (ChA) - HSG B/D
- Goldston Very Channery Silt Loam, 15 to 45 percent slopes (GoE) - HSG D
- Goldston-Badin Complex, 2 to 8 percent slopes (GsB) - HSG D
- Tarrus Gravelly Silt Loam, 2 to 8 percent slopes (TaB) - HSG B
SECTION 7 - RUNOFF CALCULATIONS
Peak flow rates for the watersheds were calculated by the SSA Program for each design storm.The
pre- and post-development drainage basins are shown in appendicies that follow this report.
Curve Numbers
Curve numbers were generated according to procedures set forth in SCS Technical
Release 55. The composite curve numbers for each drainage basin were calculated
using soils information from the Soil Survey of Union County, NC provided by The United
States Department of Agriculture Soil Conservation Service. Curve numbers were
weighted based on the land use and soil group within each basin.
Time of Concentration
Times of concentration were calculated according to procedures set forth in SCS
Technical Release (TR) 55. The travel times (Tt) for overland flow, shallow concentrated
flow, and channel flow are added together for the drainage basin to get the time of
concentration Tc.
Basin information for the area of interest was collected for use in the SSA models. Basins
were delineated using surveyed topographic information. Basins were drawn and the
most hydarulically distant flow paths were found. The times of concentration were
calculated based on the NRCS, three part travel time method documented in TR-55. The
three equations used are summarized below:
H THOMAS & HUTTON
Page 6

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
Sheet Flow: (hr) Symbol Dimension Units
0.007(nL)0'8 n Manning's n --
tl — P o.os X S°4 L Length of flow ft
z 2 yr event
P2 rainfall in
S Slope ft/ft
Shallow Concentrated Flow: (hr) Symbol Dimension Units
L L Length of flow ft
t2 3600 x V V* Velocity ft/s
*Based on TR-55 velocity-slope relationship
Channel Flow: (hr) Symbol Dimension Units
L L Length of flow ft
t3 =
3600 x V V* Velocity ft/s
*Assumed to be 2 ft/s
Time of Concentration: (hr)
t� = tl + t2 + t3
Appendices B and C with time of concentration information are attached.
SECTION 8 - EXISTING CONDITIONS
While the site itself is just over 18 acres, the total acreage of the drainage basins analyzed in the
stormwater calculations is approximately 26.9 acres. The existing conditions described in this
narrative will refer to the pre-development condition of the site. The pre-development conditions
for the site consists predominantly of wooded area with an understory of brush with about a 3-
acre grass field with an existing pond at the northernmost end of the site as well as about a 2.75-
acre area at the westmost end of the site that contains a grass field with light tree coverage.
Stormwater runoff on the site was delineated according to the existing drainage patterns found
at the site and upon the field topographic survey completed within the site. The watershed
delineation was conducted to provide a comparison for pre-development and post-
development flows. The outfall of this site discharges into Rays Fork, an existing tributary to
Richardson Creek (See Pre Development Drainage Map-Figure 4).
H THOMAS & HUTTON
Page 7

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
SECTION 9 - POST- DEVELOPMENT CONDITIONS
The post-development drainage basin is shown on the Post-Development Drainage Map
located in Figure 5 of this report. The total post-development watershed area analyzed for this
project is approximately 26.9 acres. The total post-development watershed area draining to
Outfall 01 is approximately 8.36 acres, Outfall 02 is about 0.10 acres, Outfall 03 is about 8.76
acres, Outfall 04 is about 8.72 acres, and Outfall 5 is 1.00 acre. Although this site has more post-
development discharge points than in the pre-development condition, total post-development
peak flows are less than total pre-development conditions for the 2-yr, 10-yr, and 25-yr storm
events. See Appendices B and C for pre- and post-development SSA model input and results.
See Summary of pre-development versus post-development results at the beginning of report.
After development, the site will consist of approximately 38 single family lots, public roads, private
driveways, and stormwater management features such as drainage swales, two closed bottom
sand filters, and two dry ponds. Stormwater runoff from site will be conveyed to one of two
proposed dry ponds each with a closed-bottom sand filter. The sand filters will meet North
Carolina Department of Environmental Quality pre- and post-development flows for the two (2)
year, ten (10) year, and twenty-five (25) year storm events as well as be able to accommodate
the one hundred (100) year storm event.
The proposed sand filters were designed to meet criteria found in the NCDEQ BMP Design Manual.
The dry ponds as well as each respective outfall structure and spillway have been designed to
accommodate up to the one hundred (100) year storm event. The spillway calculations can be
seen in Appendix F. The following tables illustrate the maximum water surface elevation for the two
(2) year, ten (10) year, twenty-five (25) year, and one hundred (100) year storm events.
Table 2-Sand Filter/Dry Pond SCM 01
Bottom of Pond = 534 ft
Crest of Emergency Spillway= 539.5 ft
Top of Embankment= 540 ft
Pond 01
Max Elevation
Storm Event
(f)
2-Year 537.58
10-Year 538.98
25-Year 539.53
100-Year 539.88
1" Rainfall WSEL:535.09 ft
H THOMAS & HUTTON
Page 8

TStewart's Grove Subdivision J:31540.0000
HWingate, NC February 2024
Stormwater Management Report
Table 3-Sand Filter/Dry Pond SCM 02
Bottom of Pond = 537 ft
Crest of Emergency Spillway= 539.5 ft
Top of Embankment= 540 ft
Pond 02
Max Elevation
Storm Event
(ft)
2-Year 538.63
10-Year 539.09
25-Year 539.31
100-Year 539.45
I" Rainfall WSEL:537.22 ft
H THOMAS & HUTTON
Page 9

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Figure 1
Site Location Map
J - 31540.0000
February 2024
Thomason dhuttan.ocm

°a � tr*- . • K �c {Khi;' ,-'alit t `"ti_ t i ^.::f University •
z
o
aoi 1 F W Wilson .F-
. , t4.-'.-. A
l THO&M
AS
_ , i - ..�+` T d Highway 74© _ -
' —— — 7 .' _ w,:3 ' t t' •, r°� ,� Steal a rt's Grove
F. t .. lor s i• i�i'i.r
.:,. •
.mot t• ....�: •
Site Location Map
CO•
•! `t'' O
J �,.c. j� ��'_ •
',. _� N �; 70 ,tip• i - - •N
0 '• "E • ' . I.' ' - 1
•
•
- r %. t i
`
•i,r,;.
,
.•
-
O ' , .
- 1 �, •,
r
•
rtT
.
00
. oh 4,.. • Nt
o
4.
n�'ilB 1,000 G ° "�' ‘ ''A • 1 'r"* yy�o v).. _ �('t+,R�' K .t Q
r " LM� aV
r.`ko-- - 1,000 2,000 - •�x p +,� -.. Tj,.l v 4• .
thing
13328
This map was created using geothinQ I www.geothinQ.com I Mapping Smart Land Decisions

HT
THOMAS
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Figure 2
Topographic Map
J - 31540.0000
February 2024

W O )1,..
Mrs�' 'h11,
. r 41, .• - '0' 4*-1Kilitilkff
�`� y^� p , 575'— ' T H O M A S
. .� WI . _ 57' H U T T O N
' • :; ev, �;�. o Stewart's Grove
� . � ,� '. �*• _ •>Ifk ; N •
�. Topographic Map
J� i ••. 4. ` i
•
y t^ r
) D.-
*,Tod; -ir
t
I, p . ,
.4* • ,
.'"Irr le, - - •• 1 0 P.'j 4111k p. •
40 4 at
ma's
s. , a .411 . 8/
• L! w u f ss y 4 `
,..... ,,,j,, ..rt ..c•47 '.-447
Y :0,
illk
4 • 4
. ____... . .. - ..,„ ,. -• -.
A. 1
--...... .....-- • - re
::, 1
, .e . . \
,..ibtoolit.„ ,,:a4t:11. 4,, .
: . ,..'. la1/4
41
:k: . . :\ ,:i t 4 i 1 i•it,.
, ill I 16:. . ,
yip k.... ''k ' �-' I I
43 ------- , - 11141 ' 4-41;til: t6 k
ys A,'
y 53S
1 Inch=300 Feet.- C. 40 i. 30
•
0 300 ` 600
Feet . - 4 . `\\ geothinQ
, I , 545
This map was created using geothinQ I www.geothinQ.com I Mapping Smart Land Decisions

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Figure 3
FEMA Map
J - 31540.0000
February 2024
Thomason dhutton.com

Union Coun
STATE OF NORTH CAROLINA FIRM PANEL LOCATOR DIAGRAM
Unincorporated Aty LEGENDreas , i
, / E
t..„, ...nue • uo coo FEET El s i''r' • 370234 JOINS PA.NEL 5065
..I s• ,
• . 'l507500FEEt _ l•,-...EE4E5T11SAPUAL
fTn logI oOdeFqN L1u O1aB0lYe0d Dy Toe Har Er.H n..oA0.6A0)A,R dNaD n U alAonAlLyO wgCEniAHv eSAMn N yMCe(EeaS r b RaHTsOAeh eSOfl)Doa op deE.,SUBJECT
ztaThrO
/ ' adt
Ate' ' -e•, °,,,,,; , , Area is Me area SU.,to floodIng hy the 19,annual chance flood.Areas of Speaal Flo.
MOM I== a
1 % , . t's. ''''' I ttll, al11,1C zy..,.,x
.---- ISIMISEmEOPla 1 ToSSN OF WI 2., ._ ,.,1 .. water-surface elevation of the 1,1,annual chance fia
77
,MI r . m,, SONE a No Bose Flood Elevation determined
111....111111.11.1 \' ". , la' 4,
i-------j------"E....L.NTY •, ,.
. , . SONE ar KKe Hoop EKKatIons dKKKKined
IiiMMEMENEm „, . s., 8 i ,,-
r-71' 1 '' SONE AN rerZper of Ito 3 fett lusuMly areas of.dIngl.nese r.EleKKons
.12........M11 ZONE AE
' ../--, / ..L_I---/
MIIIMMENNENNEm
if:
meats
-\. 11121.............la t ra' s ' Z"E" rd'bylVoZcVmolr:=''escrserent'red'rtiPrenocrAft
11312.......1212......1 .tl,4,, i
,,i,1,11,
-.1' Yc'
NANALAUAIAABAN
Mal................ABA N - .sy,
• .t ProtKKon aom Me las annual chance°,greater flood
SONE ASS Areas to be paeuted from I%annual chance good hy a Federal.od
1111MMENNEMEN•••••MMEM .
. _ZONE AE • Protm.n system under orate.,no ease Rood Elem.s determined.
.''
/ .
,
, gONEVE Coastal flocd zone KKIn yeloKKy hazard(cove action,Bass Flo.Elevations
= FLOODWAY AREAS IN ZONE AE
EMMEN... ANNEX
/ i / .,,.;.,e 4.,„
.
,,,", ' TIre Medway a Me cfmnnel of a stream plus any acryacent flo.aalo areas Mat must be KKI
free of eKroactment so BASH II,annual chance flood can be carded wKKout suKKantlal
Increases In flood help.
EIMIEEEE.11111.111111MMI..-. i al
t .
,.. • , . . . .-. •„-.. ,_ „ I:•:•:•I OTHER FLOOD AREAS
ZONE x Areas of 0 2,annual chance flood;areas of Isk annual chance flood wit
ZONE AE '
- - 1.---1 ,,. ' ' ane.e.KKs,lims Man I toy Or cur.drainage aKKs Ws than 1 sguare
Mlle:and areas protected by kve.from Igkannual char..d
Si,
City ant „5.3, = OTHER AREAS
DATUM INFORMATION . -_ ^1,. ...- .---TITT-VDOM1=881M5MMIIIINIIMIM,T,-, .1.17 SOO FEKK
Sp,
P'nerArSPO'Nr31;trhe7grVOntnal'IlZrnMs T:nine=her=V;!*c7f Jurisdiction
370236 s
, ,
. COASTAL BARRIER RESOURCES SYSTEM(ORS)AREAS
,
Oglerences In map features axon
FLOODING EFFECTS FROM UN,
MIDDLE FORK P g‘.1 OTHERWISE PROTECTED AREAS(OPAS)
FIRM All coordlnates on thls map are In U S Survey F.I.where ' .' „T___
1 U$Survey Foot•130013937 Meters •, c.,......d ol,,,,,...r.r...,,...,,,,,,,,,,n........,,,,„,,.,,,,.,,,...„.,...
- cc______-- las annual:name nap!.Msg.,
ZlItt.:=INLEITS,n'Iree:r;o=:rntel h7rotm=n st= scill ..6 (,. 1 ; ,,'"' o..annul...tiosdelen Wun.
,
17StfenLZA',711;13.ncIrTltr.2:O4'1=1:11C.:17Cf:POtrtnn.olAln91971.1eVI:nr, me ...6., eo
o ' CO,' ZONE X ---- Flocaway boundary
KKe been computed for ea.No.Carol.county This Waal was then applted ... ,,,,c 50•,. '
Itte:Irgrn!PRI,1 Iret%ettfOr=To'.71,11":17,gle F7rit're.,°:,":.: °^4:7".•
CMS and CPrOdA boon.
--EFeEsioi7:eOtTerieSe171":.:"t't Al
=,g'nstohu.me'r=dutZlard"=.rloorerev:t1Oreuneret=antndan 4, „,„3
'.. 1E,KK, ease spood elevat.ca.came uniform woln zone;eKKeson In
rssa
.References to Me MO Amerkan veacal...ft.
loos.Informallon for bench mar.shown on thle map please conl.Me "'. ZONE AE
No.Cano.a Geodetic Survey al the address shown below You may.. a , mons..me
canted the Information BervIces Branch of the National Geodetic Survey at 001)
713-3242 or visit ilewebelle et Mts.,.nge non goy g it,al MON I la: 594-..- • 0- ® ,.....
I,,,,,,,,,,,,i.,1,,,,,d,,,i, —_,---------/'
No.Carollna Geodello Survey County Average Vera.Datum Offset Table 3,12.11, -- mom.arum ?s,,odr,sgiwrOinstearerenrced to Om North American Ortum or
121 w.Jones street =,-t- .r°'°Tte'''' .5,0
.w.gh NC 27001 4271.• 100.,.iln...nsvir......mne 17
1810,7334MB i '1.' i. .,,,,„,„,. 1=1207tlellthletrA fre'Il'''''''''arn
,,,,„ . "" No.Caroller geodes Survey tench mea(for mom Infamagan
Demi.Peen M•alan)2,19,91 ‘i',. Intel.,lIglIM --\,._ 4' 1, :e g BNI5510,,
. I HIE.polalecl A i... (
... s•.. u
All streams I.O n the Mood Nazard C.Na Table below were studied by detail. 3702,4 q 'r.Igx7'"e4.;,'"Corliror=rC sc"1=Or'Zt
melhOdS Laing field lainoey Other floOd heard dKK.wn On Mi.Map Mel, I a a BNISSIO.
have been derlved oslng either a coastal analysls or IlmIted...a Rivanne .' • '
" .
,analyels More iryforrnalton on the flooding sources atedied by these analySee IS
' •MI 5 MAI-ills
Contained in Ole Flood...ger.Slum,report I
-nen's
536
.,
,
, ZONE AE". , ,. ...7,,,'
!"---------.- ,
,e ...,.., , 550 _
- ,-_----, -„,
ZONE%
/
5 55/t yl I
„,
pl
_ K irk
/
GRID NORTE 20NE AE art
-----fr'. '
. . ...M.
3 555_,L......___
5, 5,' ___ "1- '\
>'-'2' ' ,-----_______. 5.53
„. 4 "I D _
L.II..31
rt"" PANEL 3480J
I ,
a. FIRM
g'4. FLOOD INSURANCE RATE MAP
'
,, 7-------- 0...__, ,
J .
4.. . .0.4 x J NORTH CAROLINA
ZONE, .. '''•-',' ' , -- ', - , ,,. ra, PANEL 5464
. .-•
=-.
) . , .0 •
r 10 -
,
,
. ,
aan Ivo FEET ,, mettaperon mamma 011 femme,apemen...am
oNNUN, Ellalla,ESE.NMI
m.o.Pee OP VMS, SAM .1
A
'560 LOD FEET I Set SOO FEET 1570 000 FEET '....'.' SI.. 34.64 J
WINCAIE TONMOF SI., V. J
NOTES TO USERS
This map is for use in adrenIStenng the Habana!Flood Insurance Program II does. CKKain areas not an sp..FIO.Flaaand Area..may Pe protected by Ilood mamme...res. TINS Map reeds Mare a..wa and up.date stream channel configuratIons than thoSe MAP REPOSITORY
meas.,dent,all areas sultana to flooding,parfleularly from local drainage sources of smell RKKr to Seaton a a'Flood Protection Measures.of Me Flood InscranKK Study re,for sh.n on Me previous FIRM for Ova turissicton Tna.KKplans and floodways that were og
(rei a sue The common!,map repos.,should be consulMd for possible updated or additional infon.on on..control shuctures in gas tunsalKKon tongs.,,,rye.,pp.,a,,ous pays,may,,,,,peon amt re,,,c,,,,,,.to b,es.a now orroam
,,,,,,_ ,. , , ,,u% flood haaeld s.iforma,on channel oonfturations As a result the Flood Profiles and Floachsay riate t.les in Me Flood
Base'nap information and gKKsoalial de.used M.velop Ma FIRM were obtained from Imuranco Mudy N.M.,.contains eulPoningve hydraulic datal may relied stream channel EFFEII-VE' DATE OF FLOOD INSURANCE RATE NAP PANEL 0
OCTOBER la gOrn.1•....,„. ,E...C,111:1,1(111,1,IITIE,11,1.:LLAN
-ro.slo moredetalled a....m mem where KKee Mond Mese..10FEet and.Botsdwalm various organintionS inClUding the partiapating KKal COMmuntlyltest stale a.federal Liston:es Mat drIfer from what is shown on Mis map 0
EFFECTIVE DATE(S)OF REVISIOMS)TO THIS PANEL =...t.wr r w we N......i.,sm.m se atm
Flood insurance SI.(Flat moon Mat SCOOMperlieS 1119 FIRM Users saould be aware Mat BFEs data.supplied by.local commons..Mat mei FEMA base map specifications were layout of map panels.community map repository addresses and a Listing of Communities table .LIPV.rsZr=7,7!1,===
insurance men@ purposes only and shoutol not be used es the sole source of flood elevation me...mad e.g.!FiBM Mr st.tional.rmahon els.base map PrePara.n Panels on which each cornmunitY a tocetect
This MON Flood Insurance BIB Map(FIRM)was produced through a unique
cooperative par..,between Ihe SI.of No.Carolina and Me Federal EFFECTIVE DATE MAP NUMBER
ort nese reap features sh.n on.map such as corporate Iln.me boo.on on,mont om If,,o.have gueetions about mi....,or.estloos....a,.,,,...1 rlo.mr..
En.e...v...a....Agency(FEIN, ITe State of Nh Carolina has
date INS aVallaAN at Me erne CR IA tIliCatiOn Omen In Me Carper.linlitS May hBIB PrAS rarn in general plena Call 1-877-FENA MAP(I,.330-2627)or visit the FEW OCTOBER 16,2008 3710546400J
aterAr:clgrIlinletn:::edmry7:===nr1: Boundanes of r......,hood.,snown on me FIRM for food.sources studied by data. ...red since We map was pub4i9h8d ma,users should con.the appKKriate community weheneel.KKWasylema o„
methods were competed M cross sections and Weep..between moss seceons Phe Poodways offical or welmes to ver,cure.comMona at pmaoltotoma bounden.o.base map features 01 II
map floodplaln areas at Me local level As a pan of MIs effort,Me Male of No. ware based.mt..oormide.ons v.regard ..mewls on Me Natio.Ill Insurance Thrs snap may=tarn made that were nor considered 6 the hydrants analysis or streams lASre An accompanying Flood Insurance BEdy reb.Letter Of I.P Rectmon 0.0MR)or Salter ot Mal, te EScoa issuance SaKK reporl.ta M.o. 0
CarOlina haS joined in a COOpeMling TeChnical State agree..wlth FEMA to Pnogrant FlooKKay SW.and other NIB.nt floodwey data for noodIng sour.studwal by.alled non.hydraullc model was created during the pro.mron[RM.stmew.lonnat FIRM Amendment
Pro..and mantaln inn 00tal FIRM methods as.11 as nonencroachment*he for toodIng sources studled by Smiled dMelled
hnol.wv.,noflo.aps own.or contact the rEMA Map Service COMM'el 1-800-3584618 for wstsnes
also proclaim instructIons br deterrnmIng a ilo.vey uslng non encroachment widths tor flooding nformmion on all relmed products associated yoKK this FIRM The FEMA MEI,Service Center ''''. 1 State or AN II
www.ncfloodmaps.com sources se...Ended O..methods may also be reach.by Fax at 1.0,50 9620 a,ts web...Ns.mac ferna oos. '("g';',71: „,,,„,„„„=,,„,,,...,' ,.......051:l.1.=`,1,= %1 M, 1 Federal Emergency Management Agency..)

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Figure 4
Pre-Development Drainage Map
J - 31540.0000
February 2024
Thomason dhutton.com

;�PRE-DEVELOPMENT FLOW SCS 24-HOUR (cfs) _
G
Storm Event Basin 1 Outfall Basin 2 Outfall Basin 3 Outfall Total ,, ft^
2yr Storm 20• .18 0• .27 16• .86 37.31 �- 4° . VIII
. .....0.,_, . \ A ' ,,ilk 11 .
10yr Storm 39.14 0.56 33.1 72.8 4 .O �.y
25yr Storm 51.41 0.76 43.95 96.12 > ,- 1. , - .
Wah :.. 4‘ ,_ ' - , _ , *Ilk:_, . .i'' . ,,;; • illi, ..4. , *4 , %, . Ilit'r. . •"'"---- '
If
F. _ r t fix..
. - - t - 0
0
rliNS'
,, ►, 01 c4►
i ''�"
,:e -it 7/4
ik ' 411- ilki...- 4
6,'e .
- ...._ ,
te%
_.., _
c: t .., ijitatip. je ° ‘11: 11--' •. • is' •
,., „.• . 1 O' 4"
ii
-::) :,
\1
0 •
: ir. if ' , ,.,..•: ,
.14:= llhi Basin V . ' ,
�►. 1�2.38 ac. . .Jo � 14 i.
:�
71 .64 k•, lltaplit
4 1'
Va 2�3.6T7 � _�:`: ;� = iit `
— -\—
W, 'Oliiiiiiitik" 43/4* \ of ,
f ,-- ,__. k Basing
/' C1 0,:iiQ ac.
A r , ' @ 70.0 0r
al.
Basin ']
Ta5.00 �
��ip�� ` 14.40 ac.
,.
�§ , ` 73.85 ,,
_'` T 25.04 a . _AI '
' * A''''''''—'".•••— ,—...._,....7. 7 ....."'' / *tY( .
-\ ,
...I!. ,•••• _ t
. ''',-.----•----"-----.-...----/ ( .,.. , .,
ilk
i .+ �• - Ems, � E _.
•
‘---------- -----‘ 41* \N.N.,...... .,,, <
� � 744- -C° ' fitt, e. ..' :t ;: 4 i 1,
404 ,ii . 4 •
Ffi E, —�
°� $_ '
ledig
i •\ ski �i
_J Point of Analysis (Owl\4 * '• ' ., - o 0 ,`,
Sheet Flow '� r '•"'44 ' Es. nd
Shallow Concentrated Flow ti, ` y '.
Channel Flow se t , s / r', '' l
Rays Fork ,; �, 'Ilk . • •
Basins ''';'•. 'em. :+r. '„ a
Property Boundary : �y t, •1 '''t , R
0 25 50 100 150 200 250 300 of ,I 7 "t,
Feet '• .. t�'
1 inch=200 feet O •.,,r�- - , _.t
Fe zurebe.:31.0 iProd•ced:01/03/2024 iProd•ced 3v:MA3 I nn..fiea 1/2sn02a Neale
315a0\3154"C'\e'VA'd\315a0000'''' ''"'l"xtl ''D'un' — Pre-Development Drainage Area Exhibit
Thomas&Hutton compiled the map information from the following sources:
Data Source Date3
Aerials ESRI 01/03/202a A l/+ 1020 E U C L I O AVENUE
Topography NOAA 01/03/2024 Union County, NC CHARLO TTEH ONC 28203• TT0.201.5505
WWTTE, NC 28203 UTTON.COM
DISCLAIMER GEOGRAPHIC INFORMATION SYSTEMS
.Ra,aII pme„oe,�e,�eetl. THOMAS
yea me e m m5oee of eep eeem Ile1VOP�po�on of me ea a�oetl repRe,eo.ep,e,emamea.
a,fofhea«pay p enessofrhetlCooright 02015 by Thomfo.pull°ble tlocumenfanonofifsrespecfivetlofosefs. Stewart's Grove HUTTON COPYRIGHT 2,2020 H THOMAS.HUTTON
Copyright ORO15 by Thomas&XUXon
No part of this document maybe reproduced without written permission from an officer of Thomas&Hutton.

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Figure 5
Post-Development Drainage Map
J - 31540.0000
February 2024
Thomason dhutton.com

POST-DEVELOPMENT FLOW SCS 24-HOUR (cfs)
Storm Event Basin 1 Outfall Basin 2 Outfall Basin 3 Outfall Basin 4 Outfall Basin 5 Outfall Total `,,
2yr Storm 12.1 0.19 12.87 11.32 0.31 36.79
10yr Storm 22.94 0.39 24.77 18.88 2.48 69.46 A '
25yr Storm 29.93 0.53 32.7 26.3 4.22 93.68 " it + ' i
f 4 Ii ,1‘ — «a%
i'Ni.i\k.. .t—.•.-•,.1,..*1401.C3',.'„.1,:,l•,.i•.,
1 ' I,• - fr,
• 11,0'
►� ' fir,Y ,�'
• —itkg,1 m,-11•lii i.'t.,.'..C1'r..o..w.,..4.,.
..I. 4
. , „ , .`, M.w••♦ /! j.?� `fir k Y . _ .•..
6.
. 1\ 1
�N �. 4.
•
W1 Basin 3I,"
R R 8.926 ac. �- -;, 'adt ... (off 76.2�7 \cr.illaf,44*
,,�, 2.3.6T7
r
- ,,
eit , r de , • ,
fl r" •
- _
,, 4004%
4111114" -4A1 4
it A * -
A*. 44. *gfol . , ,. _ .... -,, 't- . . . '' •
•
s 1 ''• ''' '' • A tt '- 7.. ' '-'.'-*iii‘,..,,'. -', . - ,,.• c
- -..i,' C /Wit4 s N ,s, , (
i
Basin / ,, eft
. :� Basin
8.547 ac. t< �100 ac.
I > i` r ,
i
Ir.
to lija !
.4''111n'.-„s,., ..., \.\\ ' .' : 4N S t,i i. -i
' ' 10i0 ), / -4 �, _' '.: • -:'.,-g- ',
' '/Ik ,,1,/ - `, ` .fie i-ait
\ \/ab • try\\'� s/71� it" a-• ,�
.> � �.
,moo ,. /, .
\ i 1 --- Basin 1
,, ,,,, '�� _ 8.360 ac.
'' "'; t; ale
� � - =, (0 .84
t
(,-` In lb-- Basin ,N - - Lg.81 g I Q �� if- )
Jr' •
• - 1 .000 ac. ��: __ v .
j i
x
` i
,-'_ Qom a � � � � i,� �
Point of Analysis iiiiinto,
Sheet Flow o .4i,
Shallow Concentrated Flow k ,r; *-
Channel Flow
Rays Fork ,� '� , ' • 0• - "'Air"--
... 7!h
Post Basins •
�. t - t . r, ri
QProperty Boundary b '„ ', ';"" �..
Proposed Pond • _ x_ -
0 25 50 100 150 200 250 300
Feet __ .�• ,\, pt _ 4'1 inch=200 feet ► .' ',. / --1---GM:�►.. .
Fk zembe.a,sao leztced:o,/oan02e IRorzcs nsAa I nnmieed:2/20/202e
��,�=,M.tl,3, 0�o�,eMaplPa= m.tlaloarem Post-Development 1
Thomas&Hutton compiled the map information from the following sources:
Data Source Date
Aerials ESRI 01/03/2024 • • 1 0 2 0 E U C L I D AVENUE
r030graphy N0AA 01/03/2024 Drainage Area Exhibit CHARLOTTE, NC 28203 980.201.5505
W W W,THOMASANDHUTTON,COM
DISCLAIMER Union County, NC GEOGRAPHIC INFORMATION SYSTEMS
.�,pll pme.•oe.ce•cited. THOMAS
yea me e m m5oee of eep eeem���e�emo�of me ea a�oetl mpRe�eo.ep,e�emame Copyright Stewart's Grove &
as to tM1e pccppY c p eness of tM1e tleose seeeocM1 soe.cefo.ovoiloble tlocumentofion of its respective tlotosets. HUTTON COPYRIGHT 02020 H THOMAS a HUTTON
M1oopyrl
No part of this document maybe reproduced without written permission from an officer of Thomas&Hutton.

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix A
Hydrologic Soils Report
J - 31540.0000
February 2024
Thomason dh utlon.ocrn

a Hydrologic Soil Group—Union County,North Carolina
,,
N
(31540-Stewart's Grove Basin Soils)
$ $
W W
549803 549300 550000 550100 550200 550300 550400
34°58'46'N .. 34°58'46"N
y.'" "*.:".
c
:3TaB
.4,'.. # ' -I, - y .
s>
= / '
..
g g
4044%,,,
.BdB2 N
/ Y
l I
Q
4.
441,11t IN N-
1\ ,, i
a, Bd0-2
Ifs
it 1 '
N
t ede
GoE '4 r
C hA1 �� /
, t -.-1 f , i;
R --.14‘12011- VI :.11101jOidieht or n
1
g + lir':. 8
8
"', 1. Rays F°rK
,rOO 01 AF4) i_llia-f n© bQ etird4 aid Ilt� ar_ ---
0
34°58'16"N 34°58'16"N
549800 549900 550000 550103 550200 550300 550400
r.
3 3
N Map Scale:1:4,450 if printed on A portrait(8.5"x 11")sheet -
Mem
a N 0 50 100 200 300rs $
Feet
0 200 400 m 800 1200
Map projection:Web Mercator Coer coordinates:WGS84 Edge tics:UTM Zone 17N WGS84
USDA Natural Resources Web Soil Survey 12/29/2023
Conservation Service National Cooperative Soil Survey Page 1 of 3

Hydrologic Soil Group—Union County,North Carolina
(31540-Stewart's Grove Basin Soils)
MAP LEGEND MAP INFORMATION
Area of Interest(AOI) p c The soil surveys that comprise your AOI were mapped at
Area of Interest(AOI) 1:24,000.
0 C/D
Soils • D Warning:Soil Map may not be valid at this scale.
Soil Rating Polygons
0 A p Not rated or not available Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
n A/D Water Features line placement.The maps do not show the small areas of
Streams and Canals contrasting soils that could have been shown at a more detailed
n B scale.
Transportation
Q B/D
r4-1. Rails Please rely on the bar scale on each map sheet for map
n C measurements.
ti Interstate Highways
C/D US Routes Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
0 D Major Roads Coordinate System: Web Mercator(EPSG:3857)
n Not rated or not available Local Roads
Maps from the Web Soil Survey are based on the Web Mercator
Soil Rating Lines Background projection,which preserves direction and shape but distorts
• • A distance and area.A projection that preserves area,such as the
1111 Aerial Photography Albers equal-area conic projection,should be used if more
• • A/D accurate calculations of distance or area are required.
^r B This product is generated from the USDA-NRCS certified data as
,. B/D of the version date(s)listed below.
• r C Soil Survey Area: Union County, North Carolina
Survey Area Data: Version 24,Sep 13,2023
• • C/D
Soil map units are labeled(as space allows)for map scales
• • D 1:50,000 or larger.
• w Not rated or not available Date(s)aerial images were photographed: Apr 17,2022—May
Soil Rating Points 20,2022
p A The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
O A/D imagery displayed on these maps.As a result,some minor
• B shifting of map unit boundaries may be evident.
• B/D
USDA Natural Resources Web Soil Survey 12/29/2023
Conservation Service National Cooperative Soil Survey Page 2 of 3

Hydrologic Soil Group—Union County, North Carolina 31540-Stewart's Grove Basin Soils
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
BdB2 Badin channery silty C 26.7 60.2%
clay loam,2 to 8
percent slopes,
moderately eroded
BdC2 Badin channery silty C 13.9 31.4%
clay loam,8 to 15
percent slopes,
moderately eroded
ChA Chewacla silt loam,0 to B/D 2.0 4.5%
2 percent slopes,
frequently flooded
GoE Goldston very channery D 0.0 0.0%
silt loam, 15 to 45
percent slopes
GsB Goldston-Badin D 1.6 3.7%
complex,2 to 8
percent slopes
TaB Tarrus gravelly silt loam, B 0.1 0.1%
2 to 8 percent slopes
Totals for Area of Interest 44.3 100.0%
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.None Specified
Tie-break Rule: Higher
USDA Natural Resources Web Soil Survey 12/29/2023
Conservation Service National Cooperative Soil Survey Page 3 of 3

HT
THOMAS
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix B
Existing Conditions SSA Reports
J - 31540.0000
February 2024

Pre-Development 002-Year Page 1
Project Description
File Name 31540-Pre.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration(IOC)Ivvthod SCS TR 55
Link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting'lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
Qty
Rain Gages 1
Subbasins 3
Nodes 3
Junctions 1
Outfalls 2
Flow Diversions 0
Inlets 0
Storage Nodes 0
links 1
Channels 0
Pipes 1
Pumps 0
Orifices 0
Wens 0
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-002 Intensity inches North Carolina Union 2.00 3.64 SCS Type ll24-hr

Pre-Development 002-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 Sub-01 14.40 484.00 76.04 3.64 1.47 21.17 20.32 0 00:25:02
2 Sub-02 0.15 484.00 73.00 3.64 1.27 0.19 0.28 0 00:06:00
3 Sub-03 12.38 484.00 75.16 3.64 1.41 17.48 17.23 0 00:23:40

Pre-Development 002-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak IvhxHGL Max Mn Time of Total Total Time
ID Type Elevation (Ivhx) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Hooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 6-Jun Junction 0.00 6.00 0.00 6.00 0.00 37.04 0.00 0.00 6.00 0 00:00 0.00 0.00
2 Out-06 Outfall 0.00 37.04 0.00
3 Out-07 Outfall 0.00 0.27 0.00

Pre-Development 002-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total lime Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio Total Depth
Ratio
(ft) (ft) (ft) (%) (in) (cfs) (cfs) (ft/sec) (ft) (min)
1 Link-07 Pipe 6-Jun Out-06 289.62 0.00 0.00 0.0000 0.000 0.0130 37.04 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 002-Year Page 5
Subbas in Hydrology
Subbasin:Sub-01
Input Data
Area(ac) 14.4
Peak Rate Factor 484
Weighted Curve Number 76.04
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods&grass combination,Fair 1.53 D 82
Pond 0.64 C 99
Woods&grass combination,Fair 4.46 C 76
Woods,Fair 7.78 C 73
Composite Area&Weighted CN 14.41 76.04
Time ofConcentration
TOC Ivkthod:SCS lR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(SP0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
If=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf 0.5)(unpaved surface)
V=20.3282*(Sf 0.5)(paved surface)
V=15.0*(Sf 0.5)(grassed waterway surface)
V=10.0*(Sf'0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf^0.5)(short grass pasture surface)
V=5.0*(Sf'0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(If/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=lime of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Area(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Pre-Development 002-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.5 0 0
Flow Length(ft): 100 0 0
Slope(%): 4.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.09 0 0
Computed Flow Time(min): 17.75 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 197.7542 0 0
Slope(%): 7.585 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.38 0 0
ComputedFlowlime(min): 2.39 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.035 0.035 0
Flow Length(ft): 434.7619 952.9728 0
Channel Slope(%): 5.29 0.6296 0
Cross Section Area(ft'): 3 12 0
Wetted Perimeter(ft): 3 10 0
Velocity(ft/sec): 9.79 3.81 0
Computed Flow Time(min): 0.74 4.16 0
Total TOC(min) 25.04
Subbasin RunoffRe sults
Total Rainfall(in) 3.64
TotalRunoff(in) 1.47
PeakRunoff(cfs) 20.32
Weighted Curve Number 76.04
Time of Concentration(days hh:mm:ss) 0 00:25:02

Pre-Development 002-Year Page 7
Subbasin:Sub-01
Rainfall Intensity Graph
5
4.8 4.6
4.4
4.2
4
3.8 -
3.6
3.4
3.2
3
t 2.8 - _
c
2.6 — •
cm 2.4
m 2.2
IX 2
1.8
1.6
1.4
1.2
0.8
0.4
0.
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
22
21-
20-
19
18
17
16
15
14
13
12
o
11
0
o 10
9
8-
6.
5-
4-
3
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 002-Year Page 8
Subbasin:Sub-02
Input Data
Area(ac) 0.15
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.15 C 73
Composite Area&Weighted CN 0.15 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 3.64
TotalRunoff(in) 1.27
Peak Runoff(cfs) 0.28
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Pre-Development 002-Year Page 9
Subbasin:Sub-02
Rainfall Intensity Graph
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
_c g
2.8 _
2.6 - •
2.4
2.2
2 -
1.8 -
1.6
1.4_-
1.2
1
0.8
0.6
0.4
o.z
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.28
0.27 - -
0.26
0.25
0.24
0.23
0.22
0.21
0.2
0.19
0.18
0.17
w 0.16
o 0.15
0.14
0
S 0.13
K 0.12
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 002-Year Page 10
Subbasin:Sub-03
Input Data
Area(ac) 12.38
Peak Rate Factor 484
Weighted Curve Number 75.16
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 1.05 C 79
Woods,Fair 0.34 D 79
Woods,Fair 8.37 C 73
50-75%grass cover,Fair 0.16 D 84
50-75%grass cover,Fair 2.37 C 79
Pond 0.09 C 99
Composite Area&Weighted CN 12.38 75.16
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow Length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area OP): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(in) 3.64
Total Runoff(in) 1.41
Peak l unoff(cfs) 17.23
Weighted Curve Number 75.16
Time of Concentration(days hh:mm:ss) 0 00:23:40

Pre-Development 002-Year Page 11
Subbasin:Sub-03
Rainfall Intensity Graph
5.2
5-
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
s g
c 2.8 _
- 2.6 -
`c 2.4
ix 2.2
2 - •
1.6
1.4 -
1.2
1
0.8
0.6
0.4
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
18
17-
16
15
14
13
12
11
m 10-
O
• 9
O
C
• 8
7
6
5
4-
3
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 002-Year Page 12
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Ivhnning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (m) (cfs)
1 Link-07 289.62 0.00 0.00 0.00 0.00 0.00 0.0000 Dummy 0.000 0.000 0.0130 0.5000 0.5000 0.0000 0.00 No 1

Pre-Development 002-Year Page 13
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min)
1 L nk-07 37.04 0 12:15 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 010-Year Page 1
Project Description
File Name 31540-Pre.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration(IOC)Ivvthod SCS TR 55
Link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting'lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
Qty
Rain Gages 1
Subbasins 3
Nodes 3
Junctions 1
Outfalls 2
Flow Diversions 0
Inlets 0
Storage Nodes 0
links 1
Channels 0
Pipes 1
Pumps 0
Orifices 0
Wens 0
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-010 Intensity inches North Carolina Union 10.00 5.33 SCS Type ll24-hr

Pre-Development 010-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 Sub-01 14.40 484.00 76.04 5.33 2.81 40.52 39.75 0 00:25:02
2 Sub-02 0.15 484.00 73.00 5.33 2.54 0.38 0.58 0 00:06:00
3 Sub-03 12.38 484.00 75.16 5.33 2.73 33.84 34.08 0 00:23:40

Pre-Development 010-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak IvhxHGL Max Mn Time of Total Total Time
ID Type Elevation (Ivhx) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Hooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 6-Jun Junction 0.00 6.00 0.00 6.00 0.00 72.24 0.00 0.00 6.00 0 00:00 0.00 0.00
2 Out-06 Outfall 0.00 72.24 0.00
3 Out-07 Outfall 0.00 0.56 0.00

Pre-Development 010-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total lime Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio Total Depth
Ratio
(ft) (ft) (ft) (%) (in) (cfs) (cfs) (ft/sec) (ft) (min)
1 Link-07 Pipe 6-Jun Out-06 289.62 0.00 0.00 0.0000 0.000 0.0130 72.24 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 010-Year Page 5
Subbas in Hydrology
Subbasin:Sub-01
Input Data
Area(ac) 14.4
Peak Rate Factor 484
Weighted Curve Number 76.04
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods&grass combination,Fair 1.53 D 82
Pond 0.64 C 99
Woods&grass combination,Fair 4.46 C 76
Woods,Fair 7.78 C 73
Composite Area&Weighted CN 14.41 76.04
Time ofConcentration
TOC Ivkthod:SCS lR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(SP0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
If=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf 0.5)(unpaved surface)
V=20.3282*(Sf 0.5)(paved surface)
V=15.0*(Sf 0.5)(grassed waterway surface)
V=10.0*(Sf'0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf^0.5)(short grass pasture surface)
V=5.0*(Sf'0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(If/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=lime of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Area(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Pre-Development 010-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.5 0 0
Flow Length(ft): 100 0 0
Slope(%): 4.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.09 0 0
Computed Flow Time(min): 17.75 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 197.7542 0 0
Slope(%): 7.585 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.38 0 0
ComputedFlowlime(min): 2.39 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.035 0.035 0
Flow Length(ft): 434.7619 952.9728 0
Channel Slope(%): 5.29 0.6296 0
Cross Section Area(ft'): 3 12 0
Wetted Perimeter(ft): 3 10 0
Velocity(ft/sec): 9.79 3.81 0
Computed Flow Time(min): 0.74 4.16 0
Total TOC(min) 25.04
Subbasin RunoffResults
Total Rainfall(in) 5.33
Total Runoff(in) 2.81
PeakRunoff(cfs) 39.75
Weighted Curve Number 76.04
Time of Concentration(days hh:mm:ss) 0 00:25:02

Pre-Development 010-Year Page 7
Subbasin:Sub-01
Rainfall Intensity Graph
7.5
7
6.5-
6
5.5
5
4.5
-
c 4
m
c 3.5
m -
IX 3
2.5 •
2
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
42
40-
38-
36
34
32
30
28
26-
w 24
22
c 20-
18
16
14
12-
10-
8
6
4
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 010-Year Page 8
Subbasin:Sub-02
Input Data
Area(ac) 0.15
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.15 C 73
Composite Area&Weighted CN 0.15 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 5.33
Total Runoff(in) 2.54
Peak Runoff(cfs) 0.58
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Pre-Development 010-Year Page 9
Subbasin:Sub-02
Rainfall Intensity Graph
8
7.5
7
6.5
6
5.5
5
.c 4.5 .
c
- 4 •
2
c
3.5
3 .
2.5 .
2
1.5 •
1
0.5�
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.62
0.6
0.58
0.56
0.54
0.52
0.5
0.48
0.46
0.44
0.42
0.4
0.38
0.36
40 0.34
0.32
0 0.3
c
� 0.28
0.26
0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 010-Year Page 10
Subbasin:Sub-03
Input Data
Area(ac) 12.38
Peak Rate Factor 484
Weighted Curve Number 75.16
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 1.05 C 79
Woods,Fair 0.34 D 79
Woods,Fair 8.37 C 73
50-75%grass cover,Fair 0.16 D 84
50-75%grass cover,Fair 2.37 C 79
Pond 0.09 C 99
Composite Area&Weighted CN 12.38 75.16
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow Length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area OP): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(in) 5.33
Total Runoff(in) 2.73
Peak l unoff(cfs) 34.08
Weighted Curve Number 75.16
Tune of Concentration(days hh:mm:ss) 0 00:23:40

Pre-Development 010-Year Page 11
Subbasin:Sub-03
Rainfall Intensity Graph
8
7.5
7
6.5
6
5.5
5
t 4.5
c
— 4 •
m
c
.@ 3.5-
3-
2.5
2
1.5 •
1
0.5�
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
36
34-
32
30
28
26
24
22
w 20
o
18
O
C
16
14
12
10
8
6
4
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 010-Year Page 12
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Ivhnning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (m) (cfs)
1 Link-07 289.62 0.00 0.00 0.00 0.00 0.00 0.0000 Dummy 0.000 0.000 0.0130 0.5000 0.5000 0.0000 0.00 No 1

Pre-Development 010-Year Page 13
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min)
1 L nk-07 72.24 0 12:15 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 025-Year Page 1
Project Description
File Name 31540-Pre.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration(IOC)Ivvthod SCS TR 55
Link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting'lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
Qty
Rain Gages 1
Subbasins 3
Nodes 3
Junctions 1
Outfalls 2
Flow Diversions 0
Inlets 0
Storage Nodes 0
links 1
Channels 0
Pipes 1
Pumps 0
Orifices 0
Wens 0
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series IS-025 Intensity inches North Carolina Union 25.00 6.37 SCS Type ll24-hr

Pre-Development 025-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 Sub-01 14.40 484.00 76.04 6.37 3.71 53.38 52.41 0 00:25:02
2 Sub-02 0.15 484.00 73.00 6.37 3.40 0.50 0.77 0 00:06:00
3 Sub-03 12.38 484.00 75.16 6.37 3.62 44.76 45.28 0 00:23:40

Pre-Development 025-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak IvhxHGL Max Mn Time of Total Total Time
ID Type Elevation (Ivhx) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Hooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 6-Jun Junction 0.00 6.00 0.00 6.00 0.00 95.14 0.00 0.00 6.00 0 00:00 0.00 0.00
2 Out-06 Outfall 0.00 95.14 0.00
3 Out-07 Outfall 0.00 0.76 0.00

Pre-Development 025-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total lime Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio Total Depth
Ratio
(ft) (ft) (ft) (%) (in) (cfs) (cfs) (ft/sec) (ft) (min)
1 Link-07 Pipe 6-Jun Out-06 289.62 0.00 0.00 0.0000 0.000 0.0130 95.14 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 025-Year Page 5
Subbas in Hydrology
Subbasin:Sub-01
Input Data
Area(ac) 14.4
Peak Rate Factor 484
Weighted Curve Number 76.04
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods&grass combination,Fair 1.53 D 82
Pond 0.64 C 99
Woods&grass combination,Fair 4.46 C 76
Woods,Fair 7.78 C 73
Composite Area&Weighted CN 14.41 76.04
Time ofConcentration
TOC Ivkthod:SCS lR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(SP0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
If=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf 0.5)(unpaved surface)
V=20.3282*(Sf 0.5)(paved surface)
V=15.0*(Sf 0.5)(grassed waterway surface)
V=10.0*(Sf'0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf^0.5)(short grass pasture surface)
V=5.0*(Sf'0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(If/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=lime of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Area(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Pre-Development 025-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.5 0 0
Flow Length(ft): 100 0 0
Slope(%): 4.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.09 0 0
Computed Flow Time(min): 17.75 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 197.7542 0 0
Slope(%): 7.585 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.38 0 0
ComputedFlowlime(min): 2.39 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.035 0.035 0
Flow Length(ft): 434.7619 952.9728 0
Channel Slope(%): 5.29 0.6296 0
Cross Section Area(ft'): 3 12 0
Wetted Perimeter(ft): 3 10 0
Velocity(ft/sec): 9.79 3.81 0
Computed Flow Time(min): 0.74 4.16 0
Total TOC(min) 25.04
Subbasin RunoffResults
Total Rainfall(in) 6.37
TotalRunoff(in) 3.71
PeakRunoff(cfs) 52.41
Weighted Curve Number 76.04
Time of Concentration(days hh:mm:ss) 0 00:25:02

Pre-Development 025-Year Page 7
Subbasin:Sub-01
Rainfall Intensity Graph
9
8.5
8
7.5
7-
6.5
6
5.5
s 5
c
4.5
c 4-
3.5
3
2.5
2
1.5
0.5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
54
52
50
48
46
44
42
40
38
36
34
32
30
U
28
O 26
24
22
20
18
16
14
12
10
8
6
4
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 025-Year Page 8
Subbasin:Sub-02
Input Data
Area(ac) 0.15
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.15 C 73
Composite Area&Weighted CN 0.15 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 6.37
Total Runoff(in) 3.4
Peak Runoff(cfs) 0.77
Weighted Curve Number 73
Time of Concentration(days hh:mm:ss) 0 00:05:00

Pre-Development 025-Year Page 9
Subbasin:Sub-02
Rainfall Intensity Graph
9.5
9-
8.5
8
7.5
7
6.5
6-
5.5
• 5
• 4.5
c
ix 4
3.5
3
2.5
2
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.85
0.8-
0.75-
0.7
0.65
0.6
0.55
0.5-
n -
1-20.45
c 0.4
0_ 0.35
0.3
0.25
0.2
0.15
0.1
0.05
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 025-Year Page 10
Subbasin:Sub-03
Input Data
Area(ac) 12.38
Peak Rate Factor 484
Weighted Curve Number 75.16
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 1.05 C 79
Woods,Fair 0.34 D 79
Woods,Fair 8.37 C 73
50-75%grass cover,Fair 0.16 D 84
50-75%grass cover,Fair 2.37 C 79
Pond 0.09 C 99
Composite Area&Weighted CN 12.38 75.16
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow Length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area OP): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(in) 6.37
Total Runoff(in) 3.62
Peak l unoff(cfs) 45.28
Weighted Curve Number 75.16
Tune of Concentration(days hh:mm:ss) 0 00:23:40

Pre-Development 025-Year Page 11
Subbasin:Sub-03
Rainfall Intensity Graph
9.5
9-
8.5
8
7.5
7
6.5
6-
5.5
• 5
• 4.5
c
4
3.5
3
2.5
2
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
46
44
42-
40
38-
36
34
32-
30
28
26-
24
c 22
I• 20
18
16-
14
12
10-
8-
6-
4-
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 025-Year Page 12
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Ivhnning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (m) (cfs)
1 Link-07 289.62 0.00 0.00 0.00 0.00 0.00 0.0000 Dummy 0.000 0.000 0.0130 0.5000 0.5000 0.0000 0.00 No 1

Pre-Development 025-Year Page 13
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min)
1 L nk-07 95.14 0 12:15 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 100-Year Page 1
Project Description
File Name 31540-Pre.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration(IOC)Ivvthod SCS TR 55
Link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting'lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
Qty
Rain Gages 1
Subbasins 3
Nodes 3
Junctions 1
Outfalls 2
Flow Diversions 0
Inlets 0
Storage Nodes 0
links 1
Channels 0
Pipes 1
Pumps 0
Orifices 0
Wens 0
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-100 Intensity inches North Carolina Union 100.00 7.50 SCS Type II24-hr

Pre-Development 100-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 Sub-01 14.40 484.00 76.04 7.50 4.71 67.84 66.40 0 00:25:02
2 Sub-02 0.15 484.00 73.00 7.50 4.37 0.65 0.99 0 00:06:00
3 Sub-03 12.38 484.00 75.16 7.50 4.61 57.08 57.70 0 00:23:40

Pre-Development 100-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak vhxHGL Max Mn Time of Total Total Time
ID Type Elevation (Ivhx) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (fl) (fl) (fl) (ft') (cfe) (0) (0) (0) (days hh:mm) (ac-in) (min)
1 6-Jun Junction 0.00 6.00 0.00 6.00 0.00 120.38 0.00 0.00 6.00 0 00:00 0.00 0.00
2 Out-06 Outfall 0.00 120.38 0.00
3 Out-07 Outfall 0.00 0.98 0.00

Pre-Development 100-Year Page 4
link Summary
SNElement Element From To(Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total lime Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio Total Depth
Ratio
(ft) (ft) ($) (%) (in) (cfs) (cfs) ($/sec) (ft) (min)
1 Link-07 Pipe 6-Jun Out-06 289.62 0.00 0.00 0.0000 0.000 0.0130 120.38 0.00 0.00 0.00 0.00 0.00 0.00

Pre-Development 100-Year Page 5
Subbas in Hydrology
Subbasin:Sub-01
Input Data
Area(ac) 14.4
Peak Rate Factor 484
Weighted Curve Number 76.04
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods&grass combination,Fair 1.53 D 82
Pond 0.64 C 99
Woods&grass combination,Fair 4.46 C 76
Woods,Fair 7.78 C 73
Composite Area&Weighted CN 14.41 76.04
Time ofConcentration
TOC Ivkthod:SCS lR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(SP0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
If=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf 0.5)(unpaved surface)
V=20.3282*(Sf 0.5)(paved surface)
V=15.0*(Sf 0.5)(grassed waterway surface)
V=10.0*(Sf'0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf^0.5)(short grass pasture surface)
V=5.0*(Sf'0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(If/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=lime of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Area(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Pre-Development 100-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.5 0 0
Flow Length(ft): 100 0 0
Slope(%): 4.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.09 0 0
Computed Flow Time(min): 17.75 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 197.7542 0 0
Slope(%): 7.585 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.38 0 0
ComputedFlowlime(min): 2.39 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.035 0.035 0
Flow Length(ft): 434.7619 952.9728 0
Channel Slope(%): 5.29 0.6296 0
Cross Section Area(ft'): 3 12 0
Wetted Perimeter(ft): 3 10 0
Velocity(ft/sec): 9.79 3.81 0
Computed Flow Time(min): 0.74 4.16 0
Total TOC(min) 25.04
Subbasin RunoffResults
Total Rainfall(in) 7.5
Total Runoff(in) 4.71
PeakRunoff(cfs) 66.4
Weighted Curve Number 76.04
Time of Concentration(days hh:mm:ss) 0 00:25:02

Pre-Development 100-Year Page 7
Subbasin:Sub-01
Rainfall Intensity Graph
10.5
10
9.5
9
8.5
8
7.5
7
6.5
t 6
c - '
5.5
5
-
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
70
65
60
55
50
45-
w 40_
U -
35
0
c
o
30
25
20
15
10
5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 100-Year Page 8
Subbasin:Sub-02
Input Data
Area(ac) 0.15
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.15 C 73
Composite Area&Weighted CN 0.15 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 7.5
Total Runoff(in) 4.37
Peak Runoff(cfs) 0.99
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Pre-Development 100-Year Page 9
Subbasin:Sub-02
Rainfall Intensity Graph
11
10.5
10
9.5
9
8.5
8
7.5
7
6.5
• 6
ca
0• 5.5
-
5
Ce 4.5 —
4 .
3.5
3
2.5
2
1-
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
1.05
1-
0.95-
0.9
0.85
0.8
0.75
0.7
0.65-
w 0.6-
0.55
0.5
z
K 0.45
0.4
0.35
0.3-
0.25-
0.2
0.15
0.1
0.05-
r`
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 100-Year Page 10
Subbasin:Sub-03
Input Data
Area(ac) 12.38
Peak Rate Factor 484
Weighted Curve Number 75.16
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 1.05 C 79
Woods,Fair 0.34 D 79
Woods,Fair 8.37 C 73
50-75%grass cover,Fair 0.16 D 84
50-75%grass cover,Fair 2.37 C 79
Pond 0.09 C 99
Composite Area&Weighted CN 12.38 75.16
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow Length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area OP): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(in) 7.5
Total Runoff(in) 4.61
Peak l unoff(cfs) 57.7
Weighted Curve Number 75.16
Time of Concentration(days hh:mm:ss) 0 00:23:40

Pre-Development 100-Year Page 11
Subbasin:Sub-03
Rainfall Intensity Graph
11
10.5
10
9.5
9
8.5
8
7.5
7
6.5
• 6
0 5.5
m _
c 5
Ce 4.5
4
3.5
3
2.5
2
1
0.5
� 1
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
62
60
58
56
54
52
50
48
46
44
42
40
38
36
wU 34
- 32
O 301
S 28
26
24
22
20
18
16
14
12
10
6
4
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Pre-Development 100-Year Page 12
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Ivhnning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (m) (cfs)
1 Link-07 289.62 0.00 0.00 0.00 0.00 0.00 0.0000 Dummy 0.000 0.000 0.0130 0.5000 0.5000 0.0000 0.00 No 1

Pre-Development 100-Year Page 13
Pipe Results
SNElement Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) ($/sec) (min) ($) (min)
1 L nk-07 120.38 0 12:15 0.00 0.00 0.00 0.00 0.00 0.00

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix C
Proposed Conditions SSA Reports
J - 31540.0000
February 2024
Thomason dhutton.com

Post-Development 002-Year Page 1
Project Description
File Name 31540-Post.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration('IOC)Ivvthod SCS TR 55
link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
QtY
Rain Gages 1
Subbasins 5
Nodes 11
Junctions 2
Outfalls 7
Flow Diversions 0
Inlets 0
Storage Nodes 2
links 10
Channels 0
Pipes 2
Pumps 0
Orifices 4
Wens 4
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-002 Intensity inches North Carolina Union 2.00 3.64 SCS Type ll24-hr

Post-Development 002-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (n) (ac-in) (cfs) (days hh:mm:ss)
1 1 8.36 484.00 77.84 3.64 1.59 13.32 12.11 0 00:27:48
2 2 0.10 484.00 73.00 3.64 1.27 0.13 0.20 0 00:06:00
3 3 8.93 484.00 76.27 3.64 1.49 13.26 13.17 0 00:23:40
4 4 8.55 484.00 90.69 3.64 2.64 22.60 29.47 0 00:11:31
5 5 1.00 484.00 88.65 3.64 2.46 2.46 3.72 0 00:06:00

Post-Development 002-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak MaxHGL Max Mn Time of Total Total Time
ID Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 1-Jun Junction 531.50 539.25 531.50 9999.00 1.00 11.32 532.68 0.00 6.57 0 00:00 0.00 0.00
2 2-Jun Junction 534.00 540.00 534.00 9999.00 1.00 0.31 534.69 0.00 5.31 0 00:00 0.00 0.00
3 Out-Ol Outfall 530.00 12.10 530.00
4 Out-02 Outfall 530.00 0.19 530.00
5 Out-03 Outfall 530.00 12.87 530.00
6 Out-04.1 Outfall 529.00 11.32 529.00
7 Out-04.2 Outfall 530.00 0.00 530.00
8 Out-05.1 Outfall 533.00 0.31 533.00
9 Out-05.2 Outfall 530.00 0.00 530.00
10 Pond-01 Storage Node 534.00 540.00 534.00 1.00 29.44 537.58 0.00 0.00
11 Pond-02 Storage Node 537.00 540.00 537.00 1.00 3.69 538.63 0.00 0.00

Post-Development 002-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Ivfanning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total Time Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio TotalDepth
Ratio
(ft) (ft) (ft) (%) (m) (cfs) (cfs) (ft/sec) (ft) (min)
1 link-Ol Pipe 1-Jun Out-04.1 50.00 531.50 531.00 1.0000 30.000 0.0150 11.32 35.55 0.32 5.59 1.08 0.43 0.00 Calculated
2 L nk-02 Pipe 2-Jun Out-05.1 37.00 534.50 534.00 1.3500 18.000 0.0150 0.31 10.58 0.03 2.55 0.18 0.12 0.00 Calculated
3 Orifice-01 Orifice Pond-01 1-Jun 534.00 531.50 1.000 0.05
4 Orifice-01.2 Orifice Pond-01 1-Jun 534.00 531.50 15.000 0.00
5 Orifice-02 Orifice Pond-02 2-Jun 537.00 534.00 1.000 0.03
6 Orifice-02.2 Orifice Pond-02 2-Jun 537.00 534.00 24.000 0.00
7 Spillway-01 Weir Pond-Ol Out-04.2 534.00 530.00 0.00
8 Spillway-02 Weir Pond-02 Out-05.2 537.00 530.00 0.00
9 Weir-Ol Weir Pond-Ol 1-Jun 534.00 531.50 11.27
10 Weir-02 Weir Pond-02 2-Jun 537.00 534.00 0.27

Post-Development 002-Year Page 5
Subbas in Hydrology
Subbasin:1
Input Data
Area(ac) 8.36
Peak Rate Factor 484
Weighted Curve Number 77.84
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 1.52 D 79
Pond 0.64 C 99
Woods,Fair 3.75 C 73
50-75%grass cover,Fair 2.45 C 79
Composite Area&Weighted CN 8.36 77.84
Time ofConcentration
TOC Ivhthod:SCS TR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(Sf`0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
11=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf`0.5)(unpaved surface)
V=20.3282*(Sf`0.5)(paved surface)
V=15.0*(Sf`0.5)(grassed waterway surface)
V=10.0*(Sf`0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf4.5)(short grass pasture surface)
V=5.0*(Sf`0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/y/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Ana(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Post-Development 002-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.6 0 0
Flow Length(ft): 100 0 0
Slope(%): 7.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 16.74 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 120.812 0 0
Slope(%): 4.1387 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.02 0 0
ComputedFlowlime(min): 1.97 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.01 0.035 0.045
Flowlength(ft): 241.648 394.595 952.973
Channel Slope(%): 0.1 5.955 0.63
Cross SectionArea(ftz): 3 3 6
Wetted Perimeter(11): 3 3 8.47
Velocity(ft/sec): 4.71 10.39 2.09
Computed Flow Time(min): 0.85 0.63 7.61
Total TOC(min) 27.81
Subbasin RunoffRe sults
Total Rainfall(in) 3.64
TotalRunoff(in) 1.59
PeakRunoff(cfs) 12.11
Weighted Curve Number 77.84
Time of Concentration(days hh:mm:ss) 0 00:27:49

Post-Development 002-Year Page 7
Subbas in:1
Rainfall Intensity Graph
5
4.8
4.6
4.4
4.2-
4
3.8-
3.4
3.2
3
2.8-
c
2.6 •
cm 2.4- •m 2.2 •
-
IX 2-
1.8
1.6-
1.4
1.2
0.8
0.6
0.4-
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
13
12.5
12 I 11.5
11
10.5
10
9.5
9
8.5
8
m
7.5
U 7
6.5
0
6
K 5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
1
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 002-Year Page 8
Subbasin:2
Input Data
Area(ac) 0.1
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.1 C 73
Composite Area&Weighted CN 0.1 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 3.64
TotalRunoff(in) 1.27
Peak Runoff(cfs) 0.2
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 002-Year Page 9
Subbasin:2
Rainfall Intensity Graph
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
3
c 2.8
2.6 •
472-
2
2.4
ct 2.2 •
2 •
1.8
1.6
1.4 •
1.2 •
1
0.8
0.6
0.4
0.2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.2
0.19-
0.18_
0.17 Il
0.16
0.15
0.14
0.13
0.12-
40 0.11
0.1-
o
c -
K 0.09-
0.08
0.07-
0.06
0.05
0.04
0.03
0.02
0.01
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 002-Year Page 10
Subbasin:3
Input Data
Area(ac) 8.93
Peak Rate Factor 484
Weighted Curve Number 76.27
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 3.86 C 79
Woods,Fair 0.33 D 79
Woods,Fair 4.5 C 73
50-75%grass cover,Fair 0.15 D 84
Pond 0.09 C 99
Composite Area&Weighted CN 8.93 76.27
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2yr,24hrRainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow lime(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area(ft'): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(m) 3.64
Total Runoff(in) 1.49
Peak Runoff(cfs) 13.17
Weighted Curve Number 76.27
Time of Concentration(days hh:mm:ss) 0 00:23:40

Post-Development 002-Year Page 11
Subbasin:3
Rainfall Intensity Graph
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
3
c 2.8
2.6 •
472-
2
2.4
ct 2.2 •
2 •
1.8
1.6
1.4 •
1.2 •
1
0.8
0.6
0.4
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
13.5
13
12.5
12
11.5
11
10.5
10
9.5
9
8.5
8
m 7.5
5_
7
0 6.5
c
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 002-Year Page 12
Subbasin:4
Input Data
Area(ac) 8.55
Peak Rate Factor 484
Weighted Curve Number 90.69
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 7.6 C 90
Pond 0.49 C 99
OffsiteDrainage 0.31 C 100
50-75%grass cover,Fair 0.15 C 79
Composite Area&Weighted CN 8.55 90.69
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 50 0 0
Slope(%): 4 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/s ec): 0.09 0 0
Computed Flow lime(min): 8.94 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.013 0 0
Flow Length(ft): 1523.617 0 0
Channel Slope(%): 1.068 0 0
Cross Section Area(IF): 7.068 0 0
Wetted Perimeter(ft): 9.425 0 0
Velocity(ft/sec): 9.78 0 0
Computed Flow Time(min): 2.6 0 0
Total lOC(min) 11.53
Subbasin Runoff Results
Total Rainfall(in) 3.64
Total Runoff(in) 2.64
PeakRunoff(cfs) 29.47
Weighted Curve Number 90.69
Time of Concentration(days hh:mm:ss) 0 00:11:32

Post-Development 002-Year Page 13
Subbasin:4
Rainfall Intensity Graph
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
3
c 2.8
2.6 •
472—
2
2.4
ct 2.2
2 •
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
31
30
29
28
27
26
25
24
23
22
21
20
19
18 -
.20 17
16
0 15
c 14
13
12
11
10
9
8
7
6
5
4
3
2
1
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 002-Year Page 14
Subbasin:5
Input Data
Area(ac) 1
Peak Rate Factor 484
Weighted Curve Number 88.65
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 0.74 C 90
Pond 0.12 C 99
Woods,Fair 0.14 C 73
Composite Area&Weighted CN 1 88.65
Time of Concentration
User-Defined TOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 3.64
Total Runoff(in) 2.46
PeakRunoff(cfs) 3.72
Weighted Curve Number 88.65
Time of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 002-Year Page 15
Subbasin:5
Rainfall Intensity Graph
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4
3.2
3
c 2.8
2.6 •
472-
2
2.4
ct 2.2 •
2 •
1.8
1.6
1.4 •
1.2 •
1
0.8
0.6
0.4
0.2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
4
3.8
3.6
3.4
3.2
3
2.8
2.6-
2.4 U
2
o
c 1.8
1.4
1.2-
1_
0.8
0.6-
0.4
0.2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 002-Year Page 16
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (in) (cfs)
1 link-Ol 50.00 531.50 0.00 531.00 2.00 0.50 1.0000 CIRCULAR 30.000 30.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1
2 L nk-02 37.00 534.50 0.50 534.00 1.00 0.50 1.3500 CIRCULAR 18.000 18.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1

Post-Development 002-Year Page 17
Pipe Results
SN Element Peak Time of Design Flow PeakFlow/ PeakFlow Trawl PeakFlow PeakFlow Total Tune Froude Reported
ID Flow PeakFlow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (mm) (ft) (mm)
1 L nk-Ol 11.32 0 12:16 35.55 0.32 5.59 0.15 1.08 0.43 0.00 Calculated
2 L nk-02 0.31 0 12:38 10.58 0.03 2.55 0.24 0.18 0.12 0.00 Calculated

Post-Development 002-Year Page 18
Storage Nodes
Storage Node:Pond-01
Input Data
Invert Elevation(ft) 534.00
Max(Rim)Elevation(ft) 540.00
Max(Rim)Offset(ft) 6.00
Initial Water Elevation(ft) 534.00
Initial Water Depth(ft) 0.00
Ponded Area(ft5) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (It)
1 Spillway-Ol Rectangular No 539.50 5.50 20.00 0.50 3.33
2 Weir-Ol Rectangular No 536.00 2.00 2.50 1.00 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (m) (m) (ft)
1 Orifice-Ol Side CIRCULAR No 1.00 532.50 0.61
2 Orifice-01.2 Bottom Rectangular No 15.00 15.00 538.75 0.63
Output Summary Results
Peak Inflow(cfs) 29.44
Peak Lateral Inflow(cfs) 29.44
PeakOutflow(cfs) 11.32
Peak Fxflltration Flow Rate(cfm) 0
Max HGLFevation Attained(ft) 537.58
Max HGLDepth Attained(ft) 3.58
Average HGLElevation Attained(ft) 535.76
Average HGLDepth Attained(ft) 1.76
Time of MaxHGLOccurrence(days hh:mm) 0 12:16
Total Exfiltration Volume(1000-ft3) 0
Total Hooded Volume(ac-in) 0
Total lime Flooded(min) 0
Total Retention lime(sec) 0

Post-Development 002-Year Page 19
Storage Node:Pond-02
Input Data
Invert Elevation(ft) 537.00
Max(Rim)Elevation(ft) 540.00
Nhx(Rim)Offset(ft) 3.00
Initial Water Elevation(ft) 537.00
Initial Water Depth(ft) 0.00
Ponded Area(ft) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (ft)
1 Spillway-02 Rectangular No 539.50 2.50 20.00 0.50 3.33
2 Weir-02 Rectangular No 538.50 1.50 1.75 0.75 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (in) (in) (ft)
1 Orifice-02 Side CIRCULAR No 1.00 537.00 0.61
2 Orifice-02.2 Bottom Rectangular No 24.00 24.00 539.25 0.63
Output Summary Results
Peak inflow(cfs) 3.69
Peak Lateral Inflow(cfs) 3.69
Peak Outflow(cfs) 0.31
PeakFxtiltration Flow Rate(cftn) 0
Max HGLElevation Attained(ft) 538.63
Max HGLDepth Attained(ft) 1.63
Average HGLElevation Attained(ft) 538.04
Average HGLDepth Attained(ft) 1.04
Time oftvhxHGLOccurrence(days hh:mm) 0 12:38
Total Fxfltration Volume(1000-ft') 0
Total Flooded Volume(ac-in) 0
Total Time Hooded(min) 0
Total Retention Time(sec) 0

Post-Development 010-Year Page 1
Project Description
File Name 31540-Post.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration('IOC)Ivvthod SCS TR 55
link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Time Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
QtY
Rain Gages 1
Subbasins 5
Nodes 11
Junctions 2
Outfalls 7
Flow Diversions 0
Inlets 0
Storage Nodes 2
links 10
Channels 0
Pipes 2
Pumps 0
Orifices 4
Wens 4
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-010 Intensity inches North Carolina Union 10.00 5.33 SCS Type ll24-hr

Post-Development 010-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 1 8.36 484.00 77.84 5.33 2.98 24.90 23.01 0 00:27:48
2 2 0.10 484.00 73.00 5.33 2.54 0.25 0.40 0 00:06:00
3 3 8.93 484.00 76.27 5.33 2.83 25.30 25.51 0 00:23:40
4 4 8.55 484.00 90.69 5.33 4.27 36.49 46.43 0 00:11:31
5 5 1.00 484.00 88.65 5.33 4.05 4.05 6.01 0 00:06:00

Post-Development 010-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak MaxHGL Max Mn Time of Total Total Time
ID Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 1-Jun Junction 531.50 539.25 531.50 9999.00 1.00 18.88 533.13 0.00 6.12 0 00:00 0.00 0.00
2 2-Jun Junction 534.00 540.00 534.00 9999.00 1.00 2.48 535.08 0.00 4.92 0 00:00 0.00 0.00
3 Out-Ol Outfall 530.00 22.94 530.00
4 Out-02 Outfall 530.00 0.39 530.00
5 Out-03 Outfall 530.00 24.77 530.00
6 Out-04.1 Outfall 529.00 18.88 529.00
7 Out-04.2 Outfall 530.00 0.00 530.00
8 Out-05.1 Outfall 533.00 2.48 533.00
9 Out-05.2 Outfall 530.00 0.00 530.00
10 Pond-01 Storage Node 534.00 540.00 534.00 1.00 46.35 538.98 0.00 0.00
11 Pond-02 Storage Node 537.00 540.00 537.00 1.00 5.96 539.09 0.00 0.00

Post-Development 010-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Ivfanning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total Time Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio TotalDepth
Ratio
(ft) (ft) (ft) (%) (m) (cfs) (cfs) (ft/sec) (ft) (min)
1 link-Ol Pipe 1-Jun Out-04.1 50.00 531.50 531.00 1.0000 30.000 0.0150 18.88 35.55 0.53 6.32 1.46 0.59 0.00 Calculated
2 L nk-02 Pipe 2-Jun Out-05.1 37.00 534.50 534.00 1.3500 18.000 0.0150 2.48 10.58 0.23 4.38 0.54 0.36 0.00 Calculated
3 Orifice-01 Orifice Pond-01 1-Jun 534.00 531.50 1.000 0.06
4 Orifice-01.2 Orifice Pond-01 1-Jun 534.00 531.50 15.000 1.78
5 Orifice-02 Orifice Pond-02 2-Jun 537.00 534.00 1.000 0.04
6 Orifice-02.2 Orifice Pond-02 2-Jun 537.00 534.00 24.000 0.00
7 Spillway-01 Weir Pond-Ol Out-04.2 534.00 530.00 0.00
8 Spillway-02 Weir Pond-02 Out-05.2 537.00 530.00 0.00
9 Weir-Ol Weir Pond-Ol 1-Jun 534.00 531.50 17.04
10 Weir-02 Weir Pond-02 2-Jun 537.00 534.00 2.44

Post-Development 010-Year Page 5
Subbas in Hydrology
Subbasin:1
Input Data
Area(ac) 8.36
Peak Rate Factor 484
Weighted Curve Number 77.84
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 1.52 D 79
Pond 0.64 C 99
Woods,Fair 3.75 C 73
50-75%grass cover,Fair 2.45 C 79
Composite Area&Weighted CN 8.36 77.84
Time ofConcentration
TOC Ivhthod:SCS TR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(Sf`0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
11=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf`0.5)(unpaved surface)
V=20.3282*(Sf`0.5)(paved surface)
V=15.0*(Sf`0.5)(grassed waterway surface)
V=10.0*(Sf`0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf4.5)(short grass pasture surface)
V=5.0*(Sf`0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/y/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Ana(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Post-Development 010-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.6 0 0
Flow Length(ft): 100 0 0
Slope(%): 7.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 16.74 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 120.812 0 0
Slope(%): 4.1387 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.02 0 0
ComputedFlowlime(min): 1.97 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.01 0.035 0.045
Flowlength(ft): 241.648 394.595 952.973
Channel Slope(%): 0.1 5.955 0.63
Cross SectionArea(ftz): 3 3 6
Wetted Perimeter(II): 3 3 8.47
Velocity(ft/sec): 4.71 10.39 2.09
Computed Flow Time(min): 0.85 0.63 7.61
Total TOC(min) 27.81
Subbasin RunoffRe sults
Total Rainfall(in) 5.33
Total Runoff(in) 2.98
PeakRunoff(cfs) 23.01
Weighted Curve Number 77.84
Time of Concentration(days hh:mm:ss) 0 00:27:49

Post-Development 010-Year Page 7
Subbas in:1
Rainfall Intensity Graph
7.5
7
6.5-
6
5.5
5-
4.5
s`
c 4
-
( 3
2.5
2
1.5-
1_
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
24
23
22
21
20
19
18
17
16
15
14
m
t 13
12
0
Jr-
sii
, 10
9
8
7
6-
5
4
3-
2
1-
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 010-Year Page 8
Subbasin:2
Input Data
Area(ac) 0.1
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.1 C 73
Composite Area&Weighted CN 0.1 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 5.33
Total Runoff(in) 2.54
Peak Runoff(cfs) 0.4
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 010-Year Page 9
Subbasin:2
Rainfall Intensity Graph
8
7.5
7_
6.5-
6
5.5
5
s 4.5
c
m— 4
c
3.5-
3-
2.5 •
-
2-
1.5 -
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.42
0.4
0.38_
0.36
0.34
0.32
0.3
0.28
0.26-
—0.24-
15-0.22
0.2
c
0.18
0.16- •
0.14
0.12-
0.1
0.08
0.06
0.04-
0.02
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 010-Year Page 10
Subbasin:3
Input Data
Area(ac) 8.93
Peak Rate Factor 484
Weighted Curve Number 76.27
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 3.86 C 79
Woods,Fair 0.33 D 79
Woods,Fair 4.5 C 73
50-75%grass cover,Fair 0.15 D 84
Pond 0.09 C 99
Composite Area&Weighted CN 8.93 76.27
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow lime(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area(ft'): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(m) 5.33
Total Runoff(in) 2.83
Peak l unoff(cfs) 25.51
Weighted Curve Number 76.27
Tune of Concentration(days hh:mm:ss) 0 00:23:40

Post-Development 010-Year Page 11
Subbasin:3
Rainfall Intensity Graph
8
•
7.5
7_
6.5-
6
5.5
5
s 4.5
c
m- 4
c
3.5-
3-
2.5 •
-
2-
1.5 -
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
26
25
24
23
22
21
20
19
18
17
16
15
U 14
13
0
z 12
K 11
10
9
8
7
6
5
4
3
1
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 010-Year Page 12
Subbasin:4
Input Data
Area(ac) 8.55
Peak Rate Factor 484
Weighted Curve Number 90.69
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 7.6 C 90
Pond 0.49 C 99
OffsiteDrainage 0.31 C 100
50-75%grass cover,Fair 0.15 C 79
Composite Area&Weighted CN 8.55 90.69
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 50 0 0
Slope(%): 4 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/s ec): 0.09 0 0
Computed Flow lime(min): 8.94 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.013 0 0
Flow Length(ft): 1523.617 0 0
Channel Slope(%): 1.068 0 0
Cross Section Area(IF): 7.068 0 0
Wetted Perimeter(ft): 9.425 0 0
Velocity(ft/sec): 9.78 0 0
Computed Flow Time(min): 2.6 0 0
Total lOC(min) 11.53
Subbasin RunoffResults
Total Rainfall(in) 5.33
Total Runoff(in) 4.27
PeakRunoff(cfs) 46.43
Weighted Curve Number 90.69
Time of Concentration(days hh:mm:ss) 0 00:11:32

Post-Development 010-Year Page 13
Subbasin:4
Rainfall Intensity Graph
8
7.5
7_
6.5-
6
5.5
5
.c 4.5
c
m- 4
c
3.5-
3-
2.5 •
-
•
2-
1.5 -
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
50
48-
46-
44
42-
40
38
36
34
32-
30
n 28-
26_
c
o 24
22
20-
18-
16-
14-
12
10
8-
6-
4
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 010-Year Page 14
Subbasin:5
Input Data
Area(ac) 1
Peak Rate Factor 484
Weighted Curve Number 88.65
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 0.74 C 90
Pond 0.12 C 99
Woods,Fair 0.14 C 73
Composite Area&Weighted CN 1 88.65
Time of Concentration
User-Defined TOC override(minutes):5
Subbasin RunoffResults
Total Rainfall(in) 5.33
Total Runoff(in) 4.05
PeakRunoff(cfs) 6.01
Weighted Curve Number 88.65
Time of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 010-Year Page 15
Subbasin:5
Rainfall Intensity Graph
8
7.5
7_
6.5-
6
5.5
5
s 4.5
c
-
To
c
3.5-
3-
2.5 •
-
•
2-
1.5 -
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
6.2
6
5.8
5.6
5.4
5.2
5
4.8
4.6
4.4
4.2
4
3.8
3.6
3.4 -
3.2
0 3
o 2.8
2.6
2.4
2.2
2
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
0.2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 010-Year Page 16
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (in) (cfs)
1 link-Ol 50.00 531.50 0.00 531.00 2.00 0.50 1.0000 CIRCULAR 30.000 30.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1
2 L nk-02 37.00 534.50 0.50 534.00 1.00 0.50 1.3500 CIRCULAR 18.000 18.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1

Post-Development 010-Year Page 17
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (mm) (ft) (mm)
1 L nk-Ol 18.88 0 12:15 35.55 0.53 6.32 0.13 1.46 0.59 0.00 Calculated
2 L nk-02 2.48 0 12:09 10.58 0.23 4.38 0.14 0.54 0.36 0.00 Calculated

Post-Development 010-Year Page 18
Storage Nodes
Storage Node:Pond-01
Input Data
Invert Elevation(ft) 534.00
Max(Rim)Elevation(ft) 540.00
Max(Rim)Offs etHI) 6.00
Initial Water Elevation(ft) 534.00
Initial Water Depth(ft) 0.00
Ponded Area(05) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (It) (ft) (It)
1 Spillway-Ol Rectangular No 539.50 5.50 20.00 0.50 3.33
2 Weir-Ol Rectangular No 536.00 2.00 2.50 1.00 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (m) (m) (ft)
1 Orifice-Ol Side CIRCULAR No 1.00 532.50 0.61
2 Orifice-01.2 Bottom Rectangular No 15.00 15.00 538.75 0.63
Output Summary Results
Peak Inflow(cfs) 46.35
Peak Lateral Inflow(cfs) 46.35
PeakOutflow(cfs) 18.88
Peak Fxflltration Flow Rate(cfm) 0
MaxHGLElevation Attained(ft) 538.98
Max HGLDepth Attained(ft) 4.98
Average HGLElevation Attained(ft) 536.3
Average HGLDepth Attained(ft) 2.3
Time of MaxHGLOccurrence(days hh:mm) 0 12:15
Total Exfiltration Volume(1000-fl3) 0
Total Hooded Volume(ac-in) 0
Total lime Flooded(min) 0
Total Retention lime(sec) 0

Post-Development 010-Year Page 19
Storage Node:Pond-02
Input Data
Invert Elevation(ft) 537.00
Max(Rim)Elevation(ft) 540.00
Nhx(Rim)Offset(ft) 3.00
Initial Water Elevation(ft) 537.00
Initial Water Depth(ft) 0.00
Ponded Area(ft) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (ft)
1 Spillway-02 Rectangular No 539.50 2.50 20.00 0.50 3.33
2 Weir-02 Rectangular No 538.50 1.50 1.75 0.75 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (m) (in) (ft)
1 Orifice-02 Side CIRCULAR No 1.00 537.00 0.61
2 Orifice-02.2 Bottom Rectangular No 24.00 24.00 539.25 0.63
Output Summary Results
Peak inflow(cfs) 5.96
Peak Lateral Inflow(cfs) 5.96
Peak Outflow(cfs) 2.48
PeakE+dfltration Flow Rate(cftn) 0
Max HGLElevation Attained(It) 539.09
Max HGLDepth Attained(ft) 2.09
Average HGLElevation Attained(ft) 538.23
Average HGLDepth Attained(ft) 1.23
Time oftvhxHGLOccurrence(days hh:mm) 0 12:09
Total Exfiltration Volume(1000-ft') 0
Total Flooded Volume(ac-in) 0
Total Time Hooded(min) 0
Total Retention Time(sec) 0

Post-Development 025-Year Page 1
Project Description
File Name 31540-Post.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration('IOC)Ivvthod SCS TR 55
link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Tune Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
QtY
Rain Gages 1
Subbasins 5
Nodes 11
Junctions 2
Outfalls 7
Flow Diversions 0
Inlets 0
Storage Nodes 2
links 10
Channels 0
Pipes 2
Pumps 0
Orifices 4
Wens 4
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-025 Intensity inches North Carolina Union 25.00 6.37 SCS Type ll24-hr

Post-Development 025-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (n) (ac-in) (cfs) (days hh:mm:ss)
1 1 8.36 484.00 77.84 6.37 3.89 32.53 30.06 0 00:27:48
2 2 0.10 484.00 73.00 6.37 3.40 0.34 0.54 0 00:06:00
3 3 8.93 484.00 76.27 6.37 3.73 33.29 33.65 0 00:23:40
4 4 8.55 484.00 90.69 6.37 5.29 45.17 56.74 0 00:11:31
5 5 1.00 484.00 88.65 6.37 5.06 5.06 7.41 0 00:06:00

Post-Development 025-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak MaxHGL Max Mn Time of Total Total Time
ID Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 1-Jun Junction 531.50 539.25 531.50 9999.00 1.00 25.88 533.61 0.00 5.64 0 00:00 0.00 0.00
2 2-Jun Junction 534.00 540.00 534.00 9999.00 1.00 4.22 535.30 0.00 4.70 0 00:00 0.00 0.00
3 Out-Ol Outfall 530.00 29.93 530.00
4 Out-02 Outfall 530.00 0.53 530.00
5 Out-03 Outfall 530.00 32.70 530.00
6 Out-04.1 Outfall 529.00 25.88 529.00
7 Out-04.2 Outfall 530.00 0.42 530.00
8 Out-05.1 Outfall 533.00 4.22 533.00
9 Out-05.2 Outfall 530.00 0.00 530.00
10 Pond-01 Storage Node 534.00 540.00 534.00 1.00 56.66 539.53 0.00 0.00
11 Pond-02 Storage Node 537.00 540.00 537.00 1.00 7.34 539.31 0.00 0.00

Post-Development 025-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Ivfanning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total Time Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio TotalDepth
Ratio
(ft) (ft) (ft) (%) (m) (cfs) (cfs) (ft/sec) (ft) (min)
1 link-Ol Pipe 1-Jun Out-04.1 50.00 531.50 531.00 1.0000 30.000 0.0150 25.88 35.55 0.73 6.66 1.85 0.74 0.00 Calculated
2 L nk-02 Pipe 2-Jun Out-05.1 37.00 534.50 534.00 1.3500 18.000 0.0150 4.22 10.58 0.40 4.96 0.71 0.49 0.00 Calculated
3 Orifice-01 Orifice Pond-01 1-Jun 534.00 531.50 1.000 0.06
4 Orifice-01.2 Orifice Pond-01 1-Jun 534.00 531.50 15.000 6.95
5 Orifice-02 Orifice Pond-02 2-Jun 537.00 534.00 1.000 0.04
6 Orifice-02.2 Orifice Pond-02 2-Jun 537.00 534.00 24.000 0.43
7 Spillway-01 Weir Pond-Ol Out-04.2 534.00 530.00 0.42
8 Spillway-02 Weir Pond-02 Out-05.2 537.00 530.00 0.00
9 Weir-Ol Weir Pond-Ol 1-Jun 534.00 531.50 18.87
10 Weir-02 Weir Pond-02 2-Jun 537.00 534.00 3.75

Post-Development 025-Year Page 5
Subbas in Hydrology
Subbasin:1
Input Data
Area(ac) 8.36
Peak Rate Factor 484
Weighted Curve Number 77.84
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 1.52 D 79
Pond 0.64 C 99
Woods,Fair 3.75 C 73
50-75%grass cover,Fair 2.45 C 79
Composite Area&Weighted CN 8.36 77.84
Time ofConcentration
TOC Ivhthod:SCS TR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(Sf`0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
11=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf`0.5)(unpaved surface)
V=20.3282*(Sf`0.5)(paved surface)
V=15.0*(Sf`0.5)(grassed waterway surface)
V=10.0*(Sf`0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf4.5)(short grass pasture surface)
V=5.0*(Sf`0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/y/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Ana(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Post-Development 025-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.6 0 0
Flow Length(ft): 100 0 0
Slope(%): 7.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 16.74 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 120.812 0 0
Slope(%): 4.1387 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.02 0 0
ComputedFlowlime(min): 1.97 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.01 0.035 0.045
Flowlength(ft): 241.648 394.595 952.973
Channel Slope(%): 0.1 5.955 0.63
Cross SectionArea(ftz): 3 3 6
Wetted Perimeter(ft): 3 3 8.47
Velocity(ft/sec): 4.71 10.39 2.09
Computed Flow Time(min): 0.85 0.63 7.61
Total TOC(min) 27.81
Subbasin RunoffRe sults
Total Rainfall(in) 6.37
Total Runoff(in) 3.89
PeakRunoff(cfs) 30.06
Weighted Curve Number 77.84
Time of Concentration(days hh:mm:ss) 0 00:27:49

Post-Development 025-Year Page 7
Subbas in:1
Rainfall Intensity Graph
9
8.5-
8
7.5
7-
6.5
6
5.5
s 5
c
- 4.5 .
C 4_
3.5
3 .
2.5
2
1.5
0.5-
•
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
31
30
29
28
27
26
25
24
23
22
21
20
19
18 -
17
16
0 15
c 14
13
12
11
10
9
8
7
6
5
4
3
2
1
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 025-Year Page 8
Subbasin:2
Input Data
Area(ac) 0.1
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.1 C 73
Composite Area&Weighted CN 0.1 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 6.37
Total Runoff(in) 3.4
Peak Runoff(cfs) 0.54
Weighted Curve Number 73
Time of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 025-Year Page 9
Subbasin:2
Rainfall Intensity Graph
9.5
9
8.5
8
7.5
7
6.5
6-
s 5.5
• 5
• 4.5
c
ix 4
3.5
3-
2.5
2
1.5-
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.56
0.54 - -
0.52
0.5
0.48
0.46
0.44
0.42
0.4
0.38
0.36
0.34
m 0.32
O 0.3
• 0.28
0
S 0.26
K 0.24
0.22
0.2
0.18
0.16
0.14
0.12
0.1
0.08
0.06
0.04
0.02
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 025-Year Page 10
Subbasin:3
Input Data
Area(ac) 8.93
Peak Rate Factor 484
Weighted Curve Number 76.27
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 3.86 C 79
Woods,Fair 0.33 D 79
Woods,Fair 4.5 C 73
50-75%grass cover,Fair 0.15 D 84
Pond 0.09 C 99
Composite Area&Weighted CN 8.93 76.27
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow lime(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area(ft'): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(m) 6.37
Total Runoff(in) 3.73
Peak Runoff(cfs) 33.65
Weighted Curve Number 76.27
Tune of Concentration(days hh:mm:ss) 0 00:23:40

Post-Development 025-Year Page 11
Subbasin:3
Rainfall Intensity Graph
9.5
9
8.5
8
7.5
7
6.5
6-
s 5.5
• 5
• 4.5
c
4
3.5
3-
2.5
2
1.5-
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
36
34
32
30
28
26-
24
22
P0-
om
1
O8
C
• 16
14
12
10
8
6
4
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 025-Year Page 12
Subbasin:4
Input Data
Area(ac) 8.55
Peak Rate Factor 484
Weighted Curve Number 90.69
Rain Gage ID Rain Gage-001.
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 7.6 C 90
Pond 0.49 C 99
OffsiteDrainage 0.31 C 100
50-75%grass cover,Fair 0.15 C 79
Composite Area&Weighted CN 8.55 90.69
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 50 0 0
Slope(%): 4 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/s ec): 0.09 0 0
Computed Flow lime(min): 8.94 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.013 0 0
Flow Length(ft): 1523.617 0 0
Channel Slope(%): 1.068 0 0
Cross Section Area(IF): 7.068 0 0
Wetted Perimeter(ft): 9.425 0 0
Velocity(ft/sec): 9.78 0 0
Computed Flow Time(min): 2.6 0 0
Total lOC(min) 11.53
Subbasin Runoff Results
Total Rainfall(in) 6.37
Total Runoff(in) 5.29
PeakRunoff(cfs) 56.74
Weighted Curve Number 90.69
Time of Concentration(days hh:mm:ss) 0 00:11:32

Post-Development 025-Year Page 13
Subbasin:4
Rainfall Intensity Graph
9.5
9
8.5
8
7.5
7
6.5
6-
s 5.5
• 5
• 4.5
c
ix 4
3.5
3-
2.5
2
1.5-
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
62
60
58
56
54
52
50
48
46
44
42
40
38
- 36
U 34
32
0 30
S 28
• 26
24
22
20
18
16
14
12
10
8
6
4
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 025-Year Page 14
Subbasin:5
Input Data
Area(ac) 1
Peak Rate Factor 484
Weighted Curve Number 88.65
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 0.74 C 90
Pond 0.12 C 99
Woods,Fair 0.14 C 73
Composite Area&Weighted CN 1 88.65
Time of Concentration
User-Defined TOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 6.37
Total Runoff(in) 5.06
PeakRunoff(cfs) 7.41
Weighted Curve Number 88.65
Time of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 025-Year Page 15
Subbasin:5
Rainfall Intensity Graph
9.5
9
8.5
8
7.5
7
6.5
6-
"1-: 5.5
5 •
4.5
c
2 4
3.5 •
3_
2.5
2
1.5-
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
8
7.5 —
7
6.5
6
5.5
5
N 4.5
5
4
c
K 3.5
3
2.5
2-
1.5
1-0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 025-Year Page 16
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (in) (cfs)
1 link-Ol 50.00 531.50 0.00 531.00 2.00 0.50 1.0000 CIRCULAR 30.000 30.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1
2 L nk-02 37.00 534.50 0.50 534.00 1.00 0.50 1.3500 CIRCULAR 18.000 18.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1

Post-Development 025-Year Page 17
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (mm) (ft) (mm)
1 L nk-Ol 25.88 0 12:14 35.55 0.73 6.66 0.13 1.85 0.74 0.00 Calculated
2 L nk-02 4.22 0 12:08 10.58 0.40 4.96 0.12 0.71 0.49 0.00 Calculated

Post-Development 025-Year Page 18
Storage Nodes
Storage Node:Pond-01
Input Data
Invert Elevation(ft) 534.00
Max(Rim)Elevation(ft) 540.00
Max(Rim)Offs etHI) 6.00
Initial Water Elevation(ft) 534.00
Initial Water Depth(ft) 0.00
Ponded Area(fP) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (It)
1 Spillway-Ol Rectangular No 539.50 5.50 20.00 0.50 3.33
2 Weir-Ol Rectangular No 536.00 2.00 2.50 1.00 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (m) (m) (ft)
1 Orifice-Ol Side CIRCULAR No 1.00 532.50 0.61
2 Orifice-01.2 Bottom Rectangular No 15.00 15.00 538.75 0.63
Output Summary Results
Peak Inflow(cfs) 56.66
Peak Lateral Inflow(cfs) 56.66
PeakOutflow(cfs) 26.3
Peak Fxflltration Flow Rate(cfm) 0
Max HGLElevation Attained(ft) 539.53
MaxHGLDepth Attained(ft) 5.53
Average HGLElevation Attained(ft) 536.53
Average HGLDepth Attained(ft) 2.53
Time of MaxHGLOccurrence(days hh:mm) 0 12:14
Total Exfiltration Volume(1000-fl3) 0
Total Hooded Volume(ac-in) 0
Total lime Flooded(min) 0
Total Retention lime(sec) 0

Post-Development 025-Year Page 19
Storage Node:Pond-02
Input Data
Invert Elevation(ft) 537.00
Max(Rim)Elevation(ft) 540.00
Nhx(Rim)Offset(ft) 3.00
Initial Water Elevation(ft) 537.00
Initial Water Depth(ft) 0.00
Ponded Area(ft') 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (ft)
1 Spillway-02 Rectangular No 539.50 2.50 20.00 0.50 3.33
2 Weir-02 Rectangular No 538.50 1.50 1.75 0.75 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (in) (in) (ft)
1 Orifice-02 Side CIRCULAR No 1.00 537.00 0.61
2 Orifice-02.2 Bottom Rectangular No 24.00 24.00 539.25 0.63
Output Summary Results
Peak inflow(cfs) 7.34
Peak Lateral Inflow(cfs) 7.34
Peak Outflow(cfs) 4.22
Peak E ifitration Flow Rate(cftn) 0
Max HGLElevation Attained(It) 539.31
Max HGLDepth Attained(ft) 2.31
Average HGLElevation Attained(ft) 538.31
Average HGLDepth Attained(ft) 1.31
Time oftvhxHGLOccurrence(days hh:mm) 0 12:07
Total Exfiltration Volume(1000-ft') 0
Total Flooded Volume(ac-in) 0
Total Time Hooded(min) 0
Total Retention Time(sec) 0

Post-Development 100-Year Page 1
Project Description
File Name 31540-Post.SPF
Project Options
Flow Units CFS
Elevation Type Elevation
HydrologyMethod SCS TR 55
Time of Concentration('IOC)Ivvthod SCS TR 55
link Routing Ivlthod Hydrodynamic
Enable OwrflowPonding at Nodes YES
Skip Steady State Analysis Time Periods NO
Analysis Options
Start Analysis On 00:00:00 0:00:00
End Analysis On 00:00:00 0:00:00
Start Reporting On 00:00:00 0:00:00
Antecedent DryDays 0 days
Runoff(Dry Weather)Time Step 0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Tune Step 0 00:05:00 days hh:mm:ss
Reporting lime Step 0 00:05:00 days hh:mm:ss
Routing Time Step 30 seconds
Number of Elements
QtY
Rain Gages 1
Subbasins 5
Nodes 11
Junctions 2
Outfalls 7
Flow Diversions 0
Inlets 0
Storage Nodes 2
links 10
Channels 0
Pipes 2
Pumps 0
Orifices 4
Wens 4
Outlets 0
Pollutants 0
Land Uses 0
Rainfall Details
SN Rain Gage Data Data Source Rainfall Rain State County Return Rainfall Rainfall
ID Source ID Type Units Period Depth Distribution
(years) (inches)
49 Time Series 1S-100 Intensity inches North Carolina Union 100.00 7.50 SCS Type II24-hr

Post-Development 100-Year Page 2
Subbasin Summary
SN Subbasin Area PeakRate Weighted Total Total Total Peak Time of
ID Factor Curve Rainfall Runoff Runoff Runoff Concentration
Number Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 1 8.36 484.00 77.84 7.50 4.91 41.07 37.86 0 00:27:48
2 2 0.10 484.00 73.00 7.50 4.37 0.44 0.69 0 00:06:00
3 3 8.93 484.00 76.27 7.50 4.74 42.26 42.65 0 00:23:40
4 4 8.55 484.00 90.69 7.50 6.40 54.66 67.96 0 00:11:31
5 5 1.00 484.00 88.65 7.50 6.16 6.16 8.92 0 00:06:00

Post-Development 100-Year Page 3
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak MaxHGL Max Mn Time of Total Total Time
ID Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
(ft) (ft) (ft) (ft) (ft') (cfs) (ft) (ft) (ft) (days hh:mm) (ac-in) (min)
1 1-Jun Junction 531.50 539.25 531.50 9999.00 1.00 28.34 533.82 0.00 5.43 0 00:00 0.00 0.00
2 2-Jun Junction 534.00 540.00 534.00 9999.00 1.00 6.65 535.58 0.00 4.42 0 00:00 0.00 0.00
3 Out-Ol Outfall 530.00 37.68 530.00
4 Out-02 Outfall 530.00 0.68 530.00
5 Out-03 Outfall 530.00 41.58 530.00
6 Out-04.1 Outfall 529.00 28.34 529.00
7 Out-04.2 Outfall 530.00 15.67 530.00
8 Out-05.1 Outfall 533.00 6.65 533.00
9 Out-05.2 Outfall 530.00 0.00 530.00
10 Pond-01 Storage Node 534.00 540.00 534.00 1.00 67.79 539.88 0.00 0.00
11 Pond-02 Storage Node 537.00 540.00 537.00 1.00 8.84 539.45 0.00 0.00

Post-Development 100-Year Page 4
link Summary
SN Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Ivfanning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total Time Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/ Surcharged Condition
Node Elevation Elevation Ratio TotalDepth
Ratio
(ft) (ft) (ft) (%) (m) (cfs) (cfs) (ft/sec) (ft) (min)
1 link-Ol Pipe 1-Jun Out-04.1 50.00 531.50 531.00 1.0000 30.000 0.0150 28.34 35.55 0.80 6.72 1.98 0.80 0.00 Calculated
2 L nk-02 Pipe 2-Jun Out-05.1 37.00 534.50 534.00 1.3500 18.000 0.0150 6.65 10.58 0.63 5.49 0.96 0.65 0.00 Calculated
3 Orifice-01 Orifice Pond-01 1-Jun 534.00 531.50 1.000 0.06
4 Orifice-01.2 Orifice Pond-01 1-Jun 534.00 531.50 15.000 8.35
5 Orifice-02 Orifice Pond-02 2-Jun 537.00 534.00 1.000 0.04
6 Orifice-02.2 Orifice Pond-02 2-Jun 537.00 534.00 24.000 2.33
7 Spillway-01 Weir Pond-01 Out-04.2 534.00 530.00 15.67
8 Spillway-02 Weir Pond-02 Out-05.2 537.00 530.00 0.00
9 Weir-Ol Weir Pond-Ol 1-Jun 534.00 531.50 19.92
10 Weir-02 Weir Pond-02 2-Jun 537.00 534.00 4.28

Post-Development 100-Year Page 5
Subbas in Hydrology
Subbasin:1
Input Data
Area(ac) 8.36
Peak Rate Factor 484
Weighted Curve Number 77.84
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 1.52 D 79
Pond 0.64 C 99
Woods,Fair 3.75 C 73
50-75%grass cover,Fair 2.45 C 79
Composite Area&Weighted CN 8.36 77.84
Time ofConcentration
TOC Ivhthod:SCS TR 55
Sheet Flow Equation:
Tc=(0.007*((n*Lf)^0.8))/((P^0.5)*(Sf`0.4))
Where:
Tc=Time of Concentration(hr)
n =Ivlanning's roughness
11=Flow Length(ft)
P=2 yr,24 hr Rainfall(inches)
Sf=Slope(ft/ft)
Shallow Concentrated Flow Equation:
V=16.1345*(Sf`0.5)(unpaved surface)
V=20.3282*(Sf`0.5)(paved surface)
V=15.0*(Sf`0.5)(grassed waterway surface)
V=10.0*(Sf`0.5)(nearlybare&unfilled surface)
V=9.0*(Sin0.5)(cultivated straight rows surface)
V=7.0*(Sf4.5)(short grass pasture surface)
V=5.0*(Sf`0.5)(woodland surface)
V=2.5*(S14.5)(forestw/heavy litter surface)
Tc=(Lf/V)/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
Channel Flow Equation:
V=(1.49*(R^(2/3))*(Sf`0.5))/n
R=Aq/Wp
Tc=(Lf/y/(3600 s ec/hr)
Where:
Tc=Time of Concentration(hr)
Lf=Flow Length(ft)
R=Hydraulic Radius(ft)
Aq=Flow Ana(lt)
Wp=Wetted Perimeter(ft)
V=Velocity(ft/sec)
Sf=Slope(ft/ft)
n=tvhnnings roughness

Post-Development 100-Year Page 6
Subarea Subarea Subarea
Sheet Flow Computations A B C
Manning's Roughness: 0.6 0 0
Flow Length(ft): 100 0 0
Slope(%): 7.5 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow Time(min): 16.74 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 120.812 0 0
Slope(%): 4.1387 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.02 0 0
ComputedFlowlime(min): 1.97 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.01 0.035 0.045
Flowlength(ft): 241.648 394.595 952.973
Channel Slope(%): 0.1 5.955 0.63
Cross SectionArea(ftz): 3 3 6
Wetted Perimeter(ft): 3 3 8.47
Velocity(ft/sec): 4.71 10.39 2.09
Computed Flow Time(min): 0.85 0.63 7.61
Total TOC(min) 27.81
Subbasin RunoffRe sults
Total Rainfall(in) 7.5
Total Runoff(in) 4.91
PeakRunoff(cfs) 37.86
Weighted Curve Number 77.84
Time of Concentration(days hh:mm:ss) 0 00:27:49

Post-Development 100-Year Page 7
Subbas in:1
Rainfall Intensity Graph
10.5
10
9.5
9
8.5
8_
7.5
7
6.5
t 6 •
c
5.5'-
2 5 .
c
4
3.5
3
2.5
2_
1.5
1
0.5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
40
38-
36
34
32
30
28
26-
24
22_
20
O
o 18
16-
14
12-
10-
8
6-
4-
2-
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 100-Year Page 8
Subbasin:2
Input Data
Area(ac) 0.1
Peak Rate Factor 484
Weighted Curve Number 73
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
Woods,Fair 0.1 C 73
Composite Area&Weighted CN 0.1 73
Time ofConcentration
User-Defined'IOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 7.5
Total Runoff(in) 4.37
Peak Runoff(cfs) 0.69
Weighted Curve Number 73
Tame of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 100-Year Page 9
Subbasin:2
Rainfall Intensity Graph
11
10.5-
10
9.5 .
9_
8.5-
8 .
7.5
7.
6.5-
s
c 6
0 5.5 •
-
5
Ce 4.5
4 •
3.5
3
2.5
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
0.75
0.7 •
0.65
0.6-
0.55-
0.5
•
0.45
Co -
46 0.4
c 0.35- -
z
0.3
0.25
0.2
0.15
0.1 •
0.05
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 100-Year Page 10
Subbasin:3
Input Data
Area(ac) 8.93
Peak Rate Factor 484
Weighted Curve Number 76.27
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
50-75%grass cover,Fair 3.86 C 79
Woods,Fair 0.33 D 79
Woods,Fair 4.5 C 73
50-75%grass cover,Fair 0.15 D 84
Pond 0.09 C 99
Composite Area&Weighted CN 8.93 76.27
Time ofConcentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 100 0 0
Slope(%): 3 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/sec): 0.1 0 0
Computed Flow lime(min): 17.46 0 0
Subarea Subarea Subarea
Shallow Concentrated Flow Computations A B C
Flow Length(ft): 240.015 0 0
Slope(%): 5 0 0
Surface Type: Woodland Unpaved Unpaved
Velocity(ft/sec): 1.12 0 0
Computed Flow Tune(min): 3.57 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.027 0 0
Flow length(ft): 1414.34 0 0
Channel Slope(%): 2.616 0 0
Cross Section Area(ft'): 3 0 0
Wetted Perimeter(ft): 3 0 0
Velocity(ft/sec): 8.93 0 0
Computed Flow Time(min): 2.64 0 0
Total TOC(min) 23.67
Subbasin RunoffResults
Total Rainfall(m) 7.5
Total Runoff(in) 4.74
Peak l unoff(cfs) 42.65
Weighted Curve Number 76.27
Tune of Concentration(days hh:mm:ss) 0 00:23:40

Post-Development 100-Year Page 11
Subbasin:3
Rainfall Intensity Graph
11
10.5-
10
9.5
9_
8.5-
8 .
7.5
7.
6.5-
c 6
5.5 • .
Zs— .
5
Ce 4.5
4
3.5
3 .
2.5
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
44
42— .
40-
38
36— • .
34
32
30 •
—
28
26— . .
t 24— .
22
o .
S 20 •
• 18
16-
14— . • .
12
10-
8-
6
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 100-Year Page 12
Subbasin:4
Input Data
Area(ac) 8.55
Peak Rate Factor 484
Weighted Curve Number 90.69
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 7.6 C 90
Pond 0.49 C 99
OffsiteDrainage 0.31 C 100
50-75%grass cover,Fair 0.15 C 79
Composite Area&Weighted CN 8.55 90.69
Time of Concentration
Subarea Subarea Subarea
Sheet Flow Computations A B C
Nbnning's Roughness: 0.4 0 0
Flow Length(ft): 50 0 0
Slope(%): 4 0 0
2 yr,24 hr Rainfall(in): 3.5 0 0
Velocity(ft/s ec): 0.09 0 0
Computed Flow lime(min): 8.94 0 0
Subarea Subarea Subarea
Channel Flow Computations A B C
Manning's Roughness: 0.013 0 0
Flow Length(ft): 1523.617 0 0
Channel Slope(%): 1.068 0 0
Cross Section Area(IF): 7.068 0 0
Wetted Perimeter(ft): 9.425 0 0
Velocity(ft/sec): 9.78 0 0
Computed Flow Time(min): 2.6 0 0
Total lOC(min) 11.53
Subbasin RunoffResults
Total Rainfall(in) 7.5
Total Runoff(in) 6.4
PeakRunoff(cfs) 67.96
Weighted Curve Number 90.69
Time of Concentration(days hh:mm:ss) 0 00:11:32

Post-Development 100-Year Page 13
Subbasin:4
Rainfall Intensity Graph
11
10.5-
10
9.5
9_
8.5-
8 .
7.5
7.
6.5 •
-
c 6
0 5.5
5
Ce 4.5
4 •
3.5
3
2.5
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
75
70
65
60
55-
50
45
m -
40
c 35-
z
30-
25
20
15
10 •
5
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 100-Year Page 14
Subbasin:5
Input Data
Area(ac) 1
Peak Rate Factor 484
Weighted Curve Number 88.65
Rain Gage ID Rain Gage-001
Composite Curve Number
32 Area Soil Curve
Soil/Surface Description (acres) Group Number
1/8 acre lots,65%impervious 0.74 C 90
Pond 0.12 C 99
Woods,Fair 0.14 C 73
Composite Area&Weighted CN 1 88.65
Time of Concentration
User-Defined TOC override(minutes):5
Subbasin RunoffRe sults
Total Rainfall(in) 7.5
TotalRunoff(in) 6.16
PeakRunoff(cfs) 8.92
Weighted Curve Number 88.65
Time of Concentration(days hh:mm:ss) 0 00:05:00

Post-Development 100-Year Page 15
Subbasin:5
Rainfall Intensity Graph
11
10.5-
10
9.5
9_
8.5-
8 .
7.5
7.
6.5 •
-
c 6
m0 5.5
5
Ce 4.5
4 •
3.5
3
2.5
2
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)
Runoff Hydrograph
9.5
9
8.5
8-
7.5-
7_
6.5-
6-
5.5
Co
5
g 4.5-
z
K 4-
3.5-
3
2.5
2
1.5
1
0.5
•
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Time(hrs)

Post-Development 100-Year Page 16
Pipe Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial Flap No.of
ID Invert Invert Invert Invert Drop Slope Shape Diameter or Width Roughness Losses Losses Losses Flow Gate Barrels
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (m) (in) (cfs)
1 link-Ol 50.00 531.50 0.00 531.00 2.00 0.50 1.0000 CIRCULAR 30.000 30.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1
2 L nk-02 37.00 534.50 0.50 534.00 1.00 0.50 1.3500 CIRCULAR 18.000 18.000 0.0150 0.5000 0.5000 0.0000 0.00 No 1

Post-Development 100-Year Page 17
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Trawl Peak Flow Peak Flow Total Tune Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (mm) (ft) (mm)
1 L nk-Ol 28.34 0 12:12 35.55 0.80 6.72 0.12 1.98 0.80 0.00 Calculated
2 L nk-02 6.65 0 12:06 10.58 0.63 5.49 0.11 0.96 0.65 0.00 Calculated

Post-Development 100-Year Page 18
Storage Nodes
Storage Node:Pond-01
Input Data
Invert Elevation(ft) 534.00
Max(Rim)Elevation(ft) 540.00
Max(Rim)Offs etHI) 6.00
Initial Water Elevation(ft) 534.00
Initial Water Depth(ft) 0.00
Ponded Area(05) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (It) (ft) (It)
1 Spillway-Ol Rectangular No 539.50 5.50 20.00 0.50 3.33
2 Weir-Ol Rectangular No 536.00 2.00 2.50 1.00 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (m) (m) (ft)
1 Orifice-Ol Side CIRCULAR No 1.00 532.50 0.61
2 Orifice-01.2 Bottom Rectangular No 15.00 15.00 538.75 0.63
Output Summary Results
Peak Inflow(cfs) 67.79
Peak Lateral Inflow(cfs) 67.79
PeakOutflow(cfs) 44.01
Peak Fxflltration Flow Rate(cfm) 0
Max HGLElevation Attained(ft) 539.88
Max HGLDepth Attained(ft) 5.88
Average HGLElevation Attained(ft) 536.67
Average HGLDepth Attained(ft) 2.67
Time of MaxHGLOccurrence(days hh:mm) 0 12:12
Total Exfiltration Volume(1000-fl3) 0
Total Hooded Volume(ac-in) 0
Total lime Flooded(min) 0
Total Retention lime(sec) 0

Post-Development 100-Year Page 19
Storage Node:Pond-02
Input Data
Invert Elevation(ft) 537.00
Max(Rim)Elevation(ft) 540.00
Nhx(Rim)Offset(ft) 3.00
Initial Water Elevation(ft) 537.00
Initial Water Depth(ft) 0.00
Ponded Area(ft) 1.00
Evaporation Loss 0.00
Outflow Weirs
SN Element Weir Flap Crest Crest Length Weir Total Discharge
ID Type Gate Elevation Offset Height Coefficient
(ft) (ft) (ft) (ft)
1 Spillway-02 Rectangular No 539.50 2.50 20.00 0.50 3.33
2 Weir-02 Rectangular No 538.50 1.50 1.75 0.75 3.33
Outflow Orifices
SN Element Orifice Orifice Flap Circular Rectangular Rectangular Orifice Orifice
ID Type Shape Gate Orifice Orifice Orifice Invert Coefficient
Diameter Height Width Elevation
(in) (in) (in) (ft)
1 Orifice-02 Side CIRCULAR No 1.00 537.00 0.61
2 Orifice-02.2 Bottom Rectangular No 24.00 24.00 539.25 0.63
Output Summary Results
Peak inflow(cfs) 8.84
Peak Lateral Inflow(cfs) 8.84
Peak Outflow(cfs) 6.65
Peak Fxflltration Flow Rate(cftn) 0
Max HGLElevation Attained(It) 539.45
Max HGLDepth Attained(ft) 2.45
Average HGLElevation Attained(ft) 538.37
Average HGLDepth Attained(ft) 1.37
Time oftvhxHGLOccurrence(days hh:mm) 0 12:05
Total Exfiltration Volume(1000-ft') 0
Total Flooded Volume(ac-in) 0
Total Time Hooded(min) 0
Total Retention Time(sec) 0

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix D
Sand Filter Design Calculations
J - 31540.0000
February 2024
Thomason dhutton.com

Post-Construction Water Quality Design -Sand Filter
PROJECT: Stewarts Grove POND 1
JOB NO.: 31540
CLIENT: Southbury Development
DATE: 1/31/2024
REVISED: 2/20/2024
I. DETERMINE SAND FILTER WATER QUALITY VOLUME
*METHOD ADAPTED FROM NCDEQ STORMWATER MANUAL
Drainage Area 8.547 Ac.
%Impervious 65%
Design Rainfall 1 in
df 1.5 ft
Rv 0.635
WQV design 19701 ft3
WQV actual 14776 ft3
k 3.5 ft/day
1.66 day
hmax filter(ft) WQV adj(ft3) AnnAf(ff2)
0.5 14776 29,551.89
1 14776 14,775.95
1.5 14776 9,850.63
2 14776 7,387.97
3 14776 4,925.32
4 14776 3,693.99
5 14776 2,955.19
6 14776 2,462.66
hmax selected ft
ha 1 ft
As(min) 1303 ft2
Af(min) 2035 ft2
As ft2
Af ft2 good
Water Quality Protection Volume(WQ)= 14,776 cf
Filter Bed Depth id()= 1.5 feet
Coef.Of Permeability of Filter Media(k)= 3.50 ft/day
Avg.Ht.of Water above Filter Bed(h()= 1.0 feet
Design Filter Bed Drain Time)tr)= 51 hours
Surface Area Calculation:
from above:
Surface Area(AO= 2,034.55 sf
Proposed Surface Area(Aral)= 3,900.00 sf
Sediment Forebay Volume Calculation:
Min.Rq'd.Sediment Forebay Vol.(VF5)= 2,955.19 cf
Proposed Sediment Forebay Volume(As,d)= 3,600.00 cf
Stage-Discharge for Sand Filter Calculations:
Elevation Height(hf)above Discharge
sand bed(feet) (cfs)
534 0.0 0.0000
535 1.0 0.2633
536 2.0 0.3686
537 3.0 0.4740
538 4.0 0.5793
539 5.0 0.6846
540 6.0 0.7899
Underdrain Minimum Drawdown Flow Calculation:
Minimum Drawdown Flow(Q,,)= I 0.000140 cfs
Underdrain Perforated Pipe System Calculations:
Enter#Holes per LF pipe= 20 holes/LF
Linear Feet of Pipe= 100.0 feet
Total#Holes= 2000 holes
50%Open#Holes= 1000 holes
Dia.of Perforations= 0.375 in.
Area of Single Hole(A)= 0.000767 sf
Orifice Equation= Qo=C*A*(2*g*h)C
Coefficient(C)= 0.62
Area of Single Hole(A)= 0.000767 sf
Total Area of Perforations(Arp)= 0.767 sf
Gravity(g)= 32.2
Head(h)= 2.00 ft
Underdrain Pipe Flow Capacity(Qo)= 5.40 cfs

Post-Construction Water Quality Design -Sand Filter
PROJECT: Sfewarts Grove POND 2
JOB NO.: 31540
CLIENT: Southbury Development
DATE: 1/31/2024
REVISED: 2/20/2024
I. DETERMINE SAND FILTER WATER QUALITY VOLUME
*METHOD ADAPTED FROM NCDEQ STORMWATER MANUAL
Drainage Area Ac.
%Impervious 65%
Design Rainfall 1 in
df 1.5 ft
Rv 0.635
WQV design 2305 ft3
WQV actual 1729 ft3
k 3.5 ft/day
1.66 day
hmax filter(ff) WQV adj(ff3) As+Af(ff2)
0.5 1729 3,457.58
1 1729 1,728.79
1.5 1729 1,152.53
2 1729 864.39
3 1729 576.26
4 1729 432.20
5 1729 345.76
6 1729 288.13
hmax selected ft
ha 1 ft
As(min) 152 ft2
Af(min) 238 ff2
As ff2
Af ft2 good
Water Quality Protection Volume(WQ)= 1,729 cf
Filter Bed Depth(dr)= 1.5 feet
Coef.Of Permeability of Filter Media(k)= 3.50 ft/day
Avg.Ht.of Water above Filter Bed(hr)= 1.0 feet
Design Filter Bed Drain Time(Tr)= 51 hours
Surface Area Calculation:
from above:
Surface Area(Ar)= 238.04 sf
Proposed Surface Area(Aral)= 500.00 sf
Sediment Forebay Volume Calculation:
Min.Rq'd.Sediment Forebay Vol.(Vrr)= 345.76 cf
Proposed Sediment Forebay Volume(As,d)= 400.00 cf
Stage-Discharge for Sand Filter Calculations:
Elevation Height(hf)above Discharge
sand bed(feel) (cfs)
537 0.0 0.0000
538 1.0 0.0338
539 2.0 0.0473
540 3.0 0.0608
3.0 0.0608
3.0 0.0608
Underdrain Minimum Drawdown Flow Calculation:
Minimum Drawdown Flow(Q,,,)= I 0.000016 cfs
Underdrain Perforated Pipe System Calculations:
Enter#Holes per LF pipe= 20 holes/LF
Linear Feet of Pipe= 100.0 feet
Total#Holes= 2000 holes
50%Open#Holes= 1000 holes
Dia.of Perforations= 0.375 in.
Area of Single Hole(A)= 0.000767 sf
Orifice Equation= Qo=C*A*(2*g*h)C
Coefficient(C)= 0.62
Area of Single Hole(A)= 0.000767 sf
Total Area of Perforations(A),,)= 0.767 sf
Gravity(g)= 32.2
Head(h)= 2.00 ft
Underdrain Pipe Flow Capacity(Qo)= 5.40 cfs

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix E
Riprap Outlet Protection
J - 31540.0000
February 2024
Thomason dhutton.com

Rip Rap Apron Design
Project Name: 31540.0000 - Stewarts Grove-FES Al
Drainage Specialist: Ryo Yamamoto Date: February 22,2024
Checked By: Nestor Hernandez Date: February 22,2024
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter, it
is classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter, it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): 7.0
Outlet pipe diameter,Do(in.) 36
Tailwater depth(Feet) 3.0
Tailwater Method To Be Used Max TW(Fig.8.06b)
Discharge(cfs) 35.9
Velocity(ft./s) 7.9
Step 2. Based on the tailwater conditions determined in Step 1, enter Figure 8.06a or Figure 8.06b
and determine the d50 rip rap size and minimum apron length(La). The d50 size is the median
stone size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape, and the apron width at the
outlet end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50, (ft.) 1 0.5
Minimum apron length, La(ft.) ** III .6 13
Apron width at pipe outlet(ft.) 9
Apron shape W=Do+ .4La
Apron width at outlet end(ft.) 8
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter. D.= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,nax
Minimum TW Maximum TW
Max Stone Diameter, dmax(Inches): 9
Apron Thickness (Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron
as straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It
may be necessary to increase the size of the rip rap where protection of the channel side
slopes is necessary. Where overfalls exist at pipe outlets or flows are excessive, a plunge pool
should be considered.

Figure 8.06b: Design of outlet protection from a round pipe flowing full, maximum
tailwater condition (Tw>=0.5 diameter)
3D0
Outlet n W = Do + 0.4La 120 1- f
pipe I ' I I
diametar iD _o)� La 110 - • - - : -1: _. .
i r .5D0 ;:. ,.
100 l
90 • i
1 li • ; s
1 80 - . . o,
H + A Y
." • * . rAr. . 't) I.
Q 70
pr
110
me 60. . Ar
. .. p. _ . �'A FrO r
f.
40 / j. . ....../
- 3
1pr
..r.. IF
/ J i . ::.
' ' •;1. ril • ir 1. ! : ' '
A „Amill 411, tt, L , 12 F-
., -;,"
„,.. a
VA
IM
A a
itilik .41 0
t s` Z V = 15 s ‘S ' � r ,, 64Er ,
:jr.
olaaAll
di
3 5 10 20 50 100 200 500 1000
Discharge(ft3/sec)

Rip Rap Apron Design
Project Name: 31540.0000 - Stewarts Grove-FES A26
Drainage Specialist: Ryo Yamamoto Date: February 22,2024
Checked By: Nestor Hernandez Date: February 22,2024
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter, it
is classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter, it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): 1.1
Outlet pipe diameter,Do(in.) 15
Tailwater depth(Feet) 3.5
Tailwater Method To Be Used Max TW(Fig.8.06b)
Discharge(cfs) 5.0
Velocity(ft./s) 5.8
Step 2. Based on the tailwater conditions determined in Step 1, enter Figure 8.06a or Figure 8.06b
and determine the d50 rip rap size and minimum apron length(La). The d50 size is the median
stone size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape, and the apron width at the
outlet end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50, (ft.) 1 0.5
Minimum apron length, La(ft.) ** III .6 10
Apron width at pipe outlet(ft.) 4
Apron shape W=Do+ .4La
Apron width at outlet end(ft.) 5
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter. D.= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,nax
Minimum TW Maximum TW
Max Stone Diameter, dmax(Inches): 9
Apron Thickness (Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron
as straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It
may be necessary to increase the size of the rip rap where protection of the channel side
slopes is necessary. Where overfalls exist at pipe outlets or flows are excessive, a plunge pool
should be considered.

Figure 8.06b: Design of outlet protection from a round pipe flowing full, maximum
tailwater condition (Tw>=0.5 diameter)
3D0
Outlet W = 00 + 0.4La 120
Pipe �� I�
diametar (Do) •
110
i r .5D0
QQ 70 a _ J
1
me so _ . • z i:- t. � lai . t... 1
., . .. ,
vi . . b r "F.,.
40, ... . / t
/ . '
? . .. ..�_ 3
.... - • • ' , .::::.N. /if
. .
` r 'f
, _. __ 2> -..- 4 i o• , -.
, ,
% 74- 1 - '''/
•
/1
i !, N
it
_ ,.1;0 I I 1 F r el ra i ifft7' 14 rt Af.1 Ei
. ASV 6 Abt.Apii'Arrpriirlir*:41 1 il
_ lar
3 5 10 20 50 100 200 500 1000
Discharge(ft3/sec)

Rip Rap Apron Design
Project Name: 31540.0000 - Stewarts Grove-FES A32
Drainage Specialist: Ryo Yamamoto Date: February 22,2024
Checked By: Nestor Hernandez Date: February 22,2024
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter, it
is classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter, it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): 0.3
Outlet pipe diameter,Do(in.) 15
Tailwater depth(Feet) 2.1
Tailwater Method To Be Used Max TW(Fig.8.06b)
Discharge(cfs) 1.5
Velocity(ft./s) 4.9
Step 2. Based on the tailwater conditions determined in Step 1, enter Figure 8.06a or Figure 8.06b
and determine the d50 rip rap size and minimum apron length(La). The d50 size is the median
stone size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape, and the apron width at the
outlet end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50, (ft.) 1 0.5
Minimum apron length, La(ft.) ** III .6 10
Apron width at pipe outlet(ft.) 4
Apron shape W=Do+ .4La
Apron width at outlet end(ft.) 5
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter. D.= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,nax
Minimum TW Maximum TW
Max Stone Diameter, dmax(Inches): 9
Apron Thickness (Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron
as straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It
may be necessary to increase the size of the rip rap where protection of the channel side
slopes is necessary. Where overfalls exist at pipe outlets or flows are excessive, a plunge pool
should be considered.

Figure 8.06b: Design of outlet protection from a round pipe flowing full, maximum
tailwater condition (Tw>=0.5 diameter)
3D0
Outlet W = Do + 0.4La 120 �- I
pipe I' I ,i ,
diametar (00)1 _ La 110 -- • -+• _: . .
al . , .
. . - _ 100 l
•
90 -
1 1
cc,..-.0 _. 80.: i.. pr . rig,ir .:., 4)::..„. i. tie ,, ,,, :
01
• i.. •F b A;. .
,.
me so . t. f
r 411' li
II il ty ti i ,
40, 1'f� f Jr „, i �
` . 0 .4. il 3
A I . ' ./ .. ,
. .„ ._ . . A .... .
•:, Fil lir r. , . .
t, , , ,
.. ,
1 viir,,,i 2 ..-J..,
///,' / , Ni
• !.,Aris,
1 ' , f / „/ / •' j /
<.. .",/i/ / .
mwomWM=W
4 4 4 4 44.4 • :7 '
Allirr _ Alririll'i Cn.:
, - ...-- -1:4:frAd 0 I I I I F ril 1 ra i 1M ' , F. AVA 'I "
,,,.. ,. .i w V _a dr a di l cc;
• y.4iisp f� r �• o
' 1:... v =ho I d:!'��i % ��I IPPF F. OW CIA'
3 5 10 20 PIP-
s 100 200 500 1000
Discharge(ft3/sec)

Rip Rap Apron Design
Project Name: 31540.0000 - Stewarts Grove-Pond 1
Drainage Specialist: Ryo Yamamoto Date: February 22,2024
Checked By: Nestor Hernandez Date: February 22,2024
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter, it
is classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter, it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): 8.6
Outlet pipe diameter,Do(in.) 30
Tailwater depth(Feet) 0.1
Tailwater Method To Be Used Min TW(Fig.8.06a)
Discharge(cfs) 18.9
Velocity(ft./s) 6.3
Step 2. Based on the tailwater conditions determined in Step 1, enter Figure 8.06a or Figure 8.06b
and determine the d50 rip rap size and minimum apron length(La). The d50 size is the median
stone size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape, and the apron width at the
outlet end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50, (ft.) 0.5
Minimum apron length, La(ft.) ** 16
Apron width at pipe outlet(ft.) 8
Apron shape W=Do+La
Apron width at outlet end(ft.) 19
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter. D.= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,nax
Minimum TW Maximum TW
Max Stone Diameter, dmax(Inches): 9 71=
Apron Thickness (Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron
as straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It
may be necessary to increase the size of the rip rap where protection of the channel side
slopes is necessary. Where overfalls exist at pipe outlets or flows are excessive, a plunge pool
should be considered.

Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
Outlet W = Do + La a , ..:....:---: .... .._. ...
pipe : .: . 4.
diameter (Do) :::
La —� 80 ` ��r�
• . , . . . r
iiilraili lwater 0.50o j ■ IIIIIIIIIUHIU4e4
►,�p
�a�`�tl 70 ;::.
1 .474 d
��`r o� God
..',;: :f . . . . 11I4:
� ,,.�ti, :• � 0 �,,. ,,.•..• .�.
10/
• e .p2t, i...ilimi
•
\e 1 : I- ' `. 001. _, - ' . . • 0„0 A. +. .1 . tilt f 0..1 1111
,,
:i ,: '; e7 00;i7r
i ..
31 I . - t._ I In r � l ' 1 I1IiIt!
.1111r-IS
. , , r iiiiiIiiirig :
.0 .14'Aoriorii. iiii
, ,
... . . ,
. ,
•000• . Oil :oil
20 A11 IN Mil s 1 M' 6T ,,,,,-5 .. .6„.....--: 1111111 il III el 1 bill I t IddriiirfratirAFAII 3
2 . . ..11� �lau�, ... r �Ir �• .1i
!III,•$, 1
1 MII! ._. :�'� did ' di - l'::. .:::.: . -;:._ a■ �Jim: : s; ; .,.- 01, •f" �D . .-11
III
pt 70
i ■ ■ gu ' j� svor IIM N
0 ..... _ +_.. ...r I I )/ter/ rr �' .� 1 ,I I R 2 Cl)
. !4•eY-
- 1 i MOM M 1111 i il I i: ' : .1 40.,;01111y I PP AWill r/t. , , 03
II • V = �� oii �w"I�Id iii _ 1 1111111
._ ' .. 1 nit I 1
to -" '��/��� ;.I. ' : ( i i
._.4..... V' _ >r
L .
0
3 5 10 20 51 100 200 500 1000
Discharge (ft3/sec)
I

Rip Rap Apron Design
Project Name: 31540.0000 - Stewarts Grove-Pond 2
Drainage Specialist: Ryo Yamamoto Date: February 22,2024
Checked By: Nestor Hernandez Date: February 22,2024
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter, it
is classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter, it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): 1.0
Outlet pipe diameter,Do(in.) 18
Tailwater depth(Feet) 0.1
Tailwater Method To Be Used Min TW(Fig.8.06a)
Discharge(cfs) 2.5
Velocity(ft./s) 4.4
Step 2. Based on the tailwater conditions determined in Step 1, enter Figure 8.06a or Figure 8.06b
and determine the d50 rip rap size and minimum apron length(La). The d50 size is the median
stone size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape, and the apron width at the
outlet end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50, (ft.) 0.5
Minimum apron length, La(ft.) ** 10
Apron width at pipe outlet(ft.) 5
Apron shape W=Do+La
Apron width at outlet end(ft.) 12
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter. D.= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,nax
Minimum TW Maximum TW
Max Stone Diameter, dmax(Inches): 9 71=
Apron Thickness (Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron
as straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It
may be necessary to increase the size of the rip rap where protection of the channel side
slopes is necessary. Where overfalls exist at pipe outlets or flows are excessive, a plunge pool
should be considered.

Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
Outlet W = Do + La a , .:i....:.. : .... .._. ...
pipe * je
diameter (Do) : .• ,r
A A
• La — 4 80 • f ., + �'
iiirligii lwater .c 0.5Do i i ,,,'i/ r:■ illgiplimn -
;Or rA1' 'on1eft ��70 � 'de'
eoCr Got 1 .11'".: . 104:
~ ,'a�j ri .�0 b" �� l1111
1
�, 1 .1I .., " �- y . .. 111
��J SO u 1" I. , . : '.\ 1 1,,, n'li iiii
�� .. ; : ye ` $ *. .'I . :. II.11 1#. 1
ii l In v.' P./ Irppl, , • '� I jt to 4 4 ! I1iiIt1JF" 9 - ,•, ill
$1 i.... ! I In r d *. 0 i�A�� ' 1
11 I mull IUI'' 110 !i lnmull 5 . . •6 -iii + #11111111 ■_ O 11111 f11m>= 1 ' ,Igi� � r FA
201 limo 111 r' 1 r - 3
II + #I 1111:I i 1 =, • ', 2 Ili - _ ii
1111N11,1 .,WI!I' ..4.. . . ... .4- 41 . 6 _AsigillifiriTi li
vIv�'. i
10 . 0 • ijir/4.-
11111 ■ 11 s 11-• N
i� -41;74111.1r:7
=i� innlnlu ;: : : a - : iO1Oh!
f Air11111111111111111ihit : 0 ''
111 111 .. - :t I I ..}... 1"!
: L.• 1 } v _ IIO _ b ��i� A • .' .,. .... . n_
Ole •
i
c)
Lo
,5 d l� 1 1 n I 1 12
rp-
.,v = 10 . ____mismedivisoppmilil . ! ! I ! 1 ., . _
d _
1.11111111111 . 0
3 5 10 20 50 100 200 500 1000
Discharge (ft3/sec)

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix F
Spillway Calculations
J - 31540.0000
February 2024
Thomason dhutton.com

2/22/24, 1:30 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Pond 1 ESW
Name Pond 1 ESW
Discharge 15.67
Channel Slope 0.334
Channel Bottom Width 20
Left Side Slope 3
Right Side Slope 3
Low Flow Liner
Retardence Class C 6-12 in
Vegetation Type Mix(Sod and Bunch)
Vegetation Density Fair 50-64%
Soil Type None
Rock Riprap
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Rock Riprap Straight 15.67 cfs 6.43 ft/s 0.12 ft 0.032 4 lbs/ft2 2.45 lbs/ft2 1.64 STABLE --
Unvegetated
D50 of Riprap(in):
12
https://ecmds.com/project/159783/channel-analysis/260462/show# 1/1

HT
THOMAS
&
HUTTON
Stormwater Management Report
Stewart's Grove Subdivision
Wingate, Union County, North Carolina
Appendix G
HEC-22 Report
J - 31540.0000
February 2024
Thomason dhutton.com

HEC-22
Energy Grade Line Computations
Struct. Q EGLo HGLo Total Pipe EGLi HGLi Ea EGLa Surface Elev.
ID (cfs) (ft) (ft) Loss (ft) (ft) (ft) (ft) (ft)
(ft)
Al 1 539.53 539.53 539.33
A2 39.7 540.02 539.53 _ _ 0.31 540.33 539.84 4.2 540.68 543.18
A19 _ 1.7 540.68 540.67 0.04 540.72 540.70 2.0 540.73 543.17
A3 _35.9 540.84 540.44 0.42 541.26 540.86 4.0 541.39 546.65
A20 _ 2.6 541.41 541.34 0.05 541.46 541.39 3.7 541.53 546.65
A4 _31.8 541.65 540.99 543.43 541.89 3.3 543.68 551.73
A5 _28.5 543.89 543.36 0.48 544.36 543.84 3.1 544.63 554.06
A6 _27.8 544.83 544.33 0.54 545.37 544.87 3.4 545.60 555.94
A7 _18.2 545.81 545.29 0.94 546.75 546.23 3.3 546.90 554.74
A22 _ 2.0 546.92 546.88 0.04 546.96 546.92 2.4 547.01 554.04
A8 _15.6 547.06 546.67 0.60 547.66 547.28 3.5 547.83 553.12
A9 _10.7 547.91 547.72 0.24 548.14 547.96 3.3 548.30 554.02
A10 _10.9 548.38 548.19 0.28 548.66 548.47 3.1 548.81 555.46
All _11.0 549.05 548.44 1.07 550.12 549.51 3.5 550.30 550.93
Al2 _ 7.6 550.42 550.13 0.46 550.88 550.59 3.7 551.06 552.69
A13 3.7 551.12 550.98 553.71 552.79 1.4 553.71 557.89
A23 2.1 547.85 547.81 0.03 547.88 547.84 2.5 547.93 553.12
A14 _10.5 546.06 544.92 2.70 548.75 547.62 4.7 549.40 554.96
A24 _ 3.0 549.43 549.34 0.06 549.50 549.40 4.2 549.60 554.96
A15 6.0 549.55 549.17 1.52 551.07 550.69 4.5 551.28 557.78_
A16 3.4 551.33 551.21 0.27 551.60 551.48 1.5 552.20 560.21_
A17 _ 2.9 552.24 552.15 556.80 555.67 1.5 556.80 563.13_
A18 1.6 556.86 556.71 558.46 557.67 1.1 558.46 563.13
A25 2.3 551.31 551.25 0.04 551.34 551.29 4.3 551.41 557.78
A21 2.6 543.70 543.64 547.06 545.05 2.3 547.06 551.84
A26 _ 539.53 539.53 536.94
A27 _ 5.5 539.85 539.53 0.31 540.16 539.84 4.3 540.25 543.18_
A28 4.4 540.33 540.13 543.27 542.18 1.7 543.27 546.93
A29 2.9 543.31 543.22 548.17 547.30 1.3 548.17 553.37
A30 2.1 548.19 548.14 549.04 548.80 0.9 549.12 554.20
A31 1.3 549.14 549.11 549.47 549.29 0.6 549.47 552.54
A32 539.31 539.31 538.44
A33 1.6 539.34 539.31 0.05 539.39 539.36 1.3f 539.44 552.02
T'THOMAS& HUTTON T.•\AutoCAD\Reports\HEC-221HEC-22Reporting

HEC-22
Storm Drain Computations
Structure ID Length Drainage Runoff Tc Rain"I" Runoff Known Q Total Q Pipe Full Q Velocity Velocity Invert Elevation Slope
(ft) Area Coeff"C" (min) (in/hr) "Q" (cfs) (cfs) Dia. (cfs) Full Design
From To (ac) (cfs) (in) (ft/s) (ft/s) U/S D/S
A2 Al 86 0.48 0.81 8 7.42 39.7 39.7 36 51.7 7.32 _ 8.06 536.52 536.00 0.60%
A19 A2 142_ 0.32 0.61 5 8.60 1.7 1.7 18 8.1 4.61 3.64 538.77 537.92 0.60%
A3 A2 146_ 0.36 0.84 8 7.53 35.9 35.9 36 51.7 7.32 7.90 537.39 536.52 0.60%
A20 A3 28_ 0.36 0.84 5 8.60 2.6 _ 2.6 15 6.5 5.27 5.00 537.87 537.59 1.00%
A4 A3 204_ 0.19 0.82 8 7.64 31.8 31.8 30 45.0 9.16 9.93 540.34 537.89 1.20%
A5 A4 98_ 0.16 0.87 8 7.70 28.5 28.5 30 45.0 9.16 9.69 541.52 540.34 1.20%
A6 A5 119_ 7 7.80 27.8 27.8 30 31.8 6.48 7.30 542.23 541.52 0.60%
A7 A6 144 0.15 0.88 7 7.93 18.2 18.2 24 17.5 5.58 6.33 543.59 542.73 0.60%
A22 A7 45 0.27 0.84 5 8.60 2.0 _ 2.0 15 5.0 4.08 3.82 544.61 544.34 0.60%
A8 A7 127_ 0.47 0.78 7 8.05 15.6 _ 15.6 24 17.5 5.58 6.30 544.36 543.59 0.60%
A9 A8 105_ 6 8.15 10.7 10.7 24 17.5 5.58 5.86 544.99 544.36 0.60%
A10 A9 121_ 6 8.27 10.9 _ 10.9 24 17.5 5.58 5.88 545.71 544.99 0.60%
All A10 97_ 0.64 0.66 6 8.36 11.0 11.0 18 8.1 4.61 6.24 546.79 546.21 0.60%
Al2 All 89_ 0.68 0.67 5 8.46 7.6 7.6 18 8.1 4.61 5.23 547.33 546.79 0.60%
A13 Al2 188_ 0.64 0.67 5 8.60 3.7 _ 3.7 15 10.2 8.33 7.67 552.27 547.58 2.50%
A23 A8 28_ 0.30 0.80 5 8.60 2.1 2.1 15 6.5 5.27 4.71 545.39 545.11 1.00%
A14 A6 103_ 0.25 0.80 6 8.28 10.5 10.5 15 7.1 5.77 8.54 544.71 543.48 1.20%
A24 A14 28_ 0.44 0.80 5 8.60 3.0 3.0 15 10.2 8.33 7.26 545.41 544.71 2.50%
A15 A14 175_ 0.06 0.83 5 8.44 6.0 6.0 15 7.1 5.77 6.48 546.81 544.71 1.20%
A16 A15 97_ 0.07 0.83 5 8.50 3.4 3.4 15 12.9 10.54 8.87 550.68 546.81 4.00%
A17 A16 115_ 0.19 0.84 5 8.58 2.9 _ 2.9 15 12.9 10.54 8.53 555.26 550.68 4.00%
A18 A17 28 0.22 0.82 5 8.60 1.6 1.6 15 12.9 10.54 7.11 557.38 556.26 4.00%
A25 A15 28 0.34 0.79 5 8.60 2.3 2.3 15 6.5 5.27 4.83 547.09 546.81 1.00%
A21 A4 28 0.38 0.77 5 8.60 2.6 2.6 15 20.4 16.66 11.36 544.75 541.92 10.00%
A27 A26 42 0.23 0.64 7 7.83 5.5 5.5 15 6.5 5.27 5.92 535.92 535.50 1.00%
A28 A27 150 0.30 0.65 7 7.94 4.4 4.4 15 10.8 8.82 8.37 541.62 537.42 2.80%
A29 A28 187 0.18 0.62 6 8.08 2.9 2.9 15 10.8 8.82 7.50 546.85 _ 541.62 2.80%
A30 A29 229 0.16 0.63 6 8.42 2.1 2.1 15 5.0 4.08 3.92 548.23 _ 546.85 0.60%
A31 A30 105 0.23 0.64 5 8.60 1.3 1.3 15 5.0 4.08 3.42 548.86 548.23 0.60%
A33 A32 78 0.30 0.62 5 8.60 1.6 1.6 15 7.9 6.45 5.06 538.17 537.00 1.50%
Ili THOMAS& HUTTON T:\AutoCADlReports\HEC-221HEC-22Reporting

HEC-22
Inlet Capacity Results
Structure Q=CIA/Kc Known Longitudinal Cross Cross Prey. Total Depth Gutter Spread Inlet Type Grate Grate Curb Curb Intercept Bypass Bypass Remark
(cfs) Q Slope Slope Slope Bypass Gutter d Width T Length Width Opening Opening Flow Flow Structure
(cfs) SL Sx Sw Flow Flow (ft) (ft) (ft) (in) (in) Length Height Qi Qb
(ft/ft) (ft/ft) (ft/ft) (cfs) (cfs) (in) (in) (cfs) (cfs)
A5 1.2 0.03 0.02 0.08 1.2 0.2' 2.0 3.9 Combination 35.5 23.6 35.5 4.2 1.2_ 0.1 A4
A4 1.3 0.03 0.02 0.08 0.1 1.4 0.2 2.0 4.3 Combination 35.5 23.6 35.5 4.2 1.3 0.1 A3
A18 1.6 0.03 0.02 0.08 1.6 0.2 2.0 4.6 Combination 35.5 23.6 35.5 4.2 1.4 0.1 A25
A17 1.4 0.03 0.02 0.08 1.4 0.2 2.0 4.3 Combination 35.5 23.6 35.5 4.2 1.3 0.1 A16
A16 0.5 0.03 0.02 0.08 0.1 0.6 0.2 2.0 1.8 Combination 35.5 23.6 35.5 4.2 0.6 A15
A15 0.4 0.03 0.02 0.08 0.6 1.0 0.2 2.0 3.0 Combination 35.5 23.6 35.5 4.2 0.9 0.0 A14
A21 2.6 0.03 0.02 0.08 2.6 0.3 2.0 6.4 Combination 35.5 23.6 35.5 4.2 2.1 0.5 A20
All 3.7 -1.00 0.20 0.20 3.7 0.4 10.0 2.6 Grate inlet 23.8 23.8 3.7
A19 1.7 -1.00 0.20 0.20 1.7 0.3 5.0 1.8 Grate inlet 23.8 23.8 1.7
A2 3.4 -1.00 0.03 0.08 1.0 4.4 0.3 2.0 5.9 Combination 71.0 23.6 71.0 4.2 4.4
A3 2.6 0.03 0.02 0.08 0.1 2.7 0.3 2.0 6.7 Combination 71.0 23.6 71.0 4.2 2.3 0.4 A2
A20 2.6 0.03 0.02 0.08 0.5 3.1 0.3 2.0 7.2 Combination 71.0 23.6 71.0 4.2 2.6 0.6 A2
A14 1.7 -1.00 0.02 0.08 0.0 1.7 0.2 2.0 2.0 Combination 71.0 23.6 71.0 4.2 1.7
A24 3.0 -1.00 0.02 0.08 0.4 3.5 0.3 2.0 6.2 Combination 71.0 23.6 71.0 4.2 3.5
A25 2.3 0.03 0.02 0.08 0.1 2.5 0.3 2.0 6.2 Combination 35.5 23.6 35.5 4.2 2.0 0.4 A24
A8 3.2 -1.00 0.02 0.08 0.1 3.3 0.2 2.0 5.7 Combination 71.0 23.6 71.0 4.2 3.3
A23 2.1 -1.00 0.02 0.08 0.3 2.4 0.2 2.0 3.3 Combination 71.0 23.6 71.0 4.2 2.4
A7 1.2 0.02 0.02 0.08 1.2 0.2 2.0 4.1 Combination 35.5 23.6 35.5 4.2 1.1 0.1 A8
A22 2.0 0.02 0.02 0.08 2.0 0.3 2.0 6.0 Combination 35.5 23.6 35.5 4.2 1.6 0.3 A23
A13 3.7 -1.00 0.20 0.20 3.7 0.4 10.0 2.6 Grate inlet 23.8 23.8 3.7
Al2 4.0 -1.00 0.20 0.20 4.0 0.4 10.0 2.7 Grate inlet 23.8 23.8 4.0
A31 1.3 -1.00 0.20 0.20 1.3 0.2 5.0 1.5 Grate inlet 23.8 23.8 1.3
A27 1.3 -1.00 0.20 0.20 1.3 0.2 5.0 1.5 Grate inlet 23.8 23.8 1.3
A30 0.9 0.01 0.20 0.20 0.9 0.4 5.0 1.8 Grate inlet 23.8 23.8 0.9
A29 0.9 0.02 0.20 0.20 0.9 0.3 5.0 1.6 Grate inlet 23.8 23.8 0.9
A28 1.7 0.03 0.20 0.20 1.7 0.4 5.0 2.0 Grate inlet 23.8 23.8 1.7
A33 1.6 -1.00 0.20 0.20 1.6 0.3 5.0 1.8 Grate inlet 23.8 23.8 1.6
TH THOMAS& HUTTON T:\AutoCAD\Reports\HEC-221HEC-22Reporting