SW3180606_6198 Engineer's Report Summary 9-25-18_20181026

STORMWATER MANAGEMENT
AND EROSION CONTROL DESIGN

CAVESSON SUBDIVISION
Wesley Chapel, North Carolina

for
Bowman Development Group

John H. Ross, P.E.
EAGLE ENGINEERING, INC.
2013A Van Buren Ave.
Indian Trail, NC 28079

EEI PROJECT NO.: 6198
May 25, 2018

REVISION DATE:
Initials Date
KEW 8-1-18
KEW 9-25-18

5-28-18
Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

Contents

1.0 Project Address and Summary ..................................................................................................................... 3 
2.0 Water Quality Volume Control and Peak Flow Control .............................................................................. 3 
3.0 Predeveloped ........................................................................................................................................... 3-4 
4.0 Post Developed Conditions .......................................................................................................................... 4 
5.0 Detention Stage/Storage Computations ........................................................................................................ 4 
6.0 Outlet Structures .......................................................................................................................................... 5 
7.0 Stormwater System ...................................................................................................................................... 5 
8.0 Erosion Control ............................................................................................................................................ 5 

Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

1.0 Project Address and Summary

The project is located within the City of Wesley Chapel, in Union County of North Carolina, on the east
side of Chambwood Road, between New Town Road and Potter Road. The proposed development will
include the construction of 28 single family lots.

The site was entitled as a low impact development and the construction will included only the installation
of the proposed roads, utility infrastructure, and BMP wet pond. The single family lots are intended to be
graded by each individual purchaser to accommodate a custom built home.

Runoff calculations were performed following the procedures outlined in the NCDEQ Stormwater BMP
Manual using the SCS method, while taking into consideration Section 14.5 "General Standards for
Stormwater Management" of the Village of Wesley Chapel Zoning Ordinance. Calculations are provided
in Appendix A of this report. The receiving drainage system for this site is East Fork Twelvemile Creek
(FIRM Map Number 3710449500J effective date 10/16/2008). Soils on the site consist of:

 BdB2 –Badin Channery Silty Loam, 2 to 8 percent slopes, moderately eroded, Hydrologic Soils
Group "C"
 ChA - Chewacla Silty Loam, 0 to 2 percent slopes, Hydrologic Soils Group "B/D"
 TbB2 – Tarrus Gravelly Silty Clay Loam, 2 to 8 percent slopes, moderately eroded, Hydrologic
Soils Group "B"

Weighted curve number values based on the existing and proposed soils conditions were used to calculate
pre and post development runoff. Drainage area maps supporting curve number calculation information
can be found in Appendix C.

2.0 Water Quality Volume Control and Peak Flow Control

The project is a low impact development and no water quality control will be required for the site.

3.0 Predeveloped Conditions

The existing conditions currently consist of primarily prairie style grass with pockets of dense woods
sporadically throughout the site. A small cow pond is located on the south side of the site, alongside an
existing dirt road which parallels the existing flood plain. The terrain of the site consist of moderate to
steep slopes forming natural ditches conveying overland runoff to an existing pond to the west, and to the
flood plain at the southern portion of the property.

The total pre-development drainage from the site was studied at the southwest corner of the property
within the existing flood plain. This study point is the lowest elevation of the site. See the Pre-
Development and Post Development Drainage Area Maps included in the Appendix A of this report. The
time of concentration has been calculated using TR-55 and is outlined on the drainage area maps, and
calculations. Curve Numbers (CN) were computed as a composite average of the various existing soil
types and land features in the pre-development drainage area which is the following:

 Pre-Development Area 1: CN = 75
Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018
 Pre-Development Area 2: CN = 70

Calculations have been included on the hydrographs in Appendix A of this report. See the Pre-
Development and Post Development Drainage Area Maps also included in the Appendix A of this report.

4.0 Post Developed Conditions

The development will consist of the grading of the proposed roads, BMP wet pond, and miscellaneous
drainage ditches that convey runoff into the proposed storm system. The remaining undisturbed area on
the site was treated as bypass area to be taken into consideration in terms of the overall pre/post
comparison of runoff from the site. The post development hydrographs have been modeled for the
proposed onsite improvements and the proposed bypass areas, and combined for a cumulative comparison
to the existing runoff from the site. The composite Curve Numbers calculated for the post developed
basins are the following

 Post Development Area: CN = 73
 Post Development Bypass Area 1: CN = 78
 Post Development Bypass Area 2: CN = 61

5.0 Detention Stage/Storage Computations

A wet detention pond has been designed to detain the 1-year, 2-year, 10-year, and 25-year storm
frequencies and control the 50-year and 100-year storm frequencies through proposed discharge outlet
controls. Due to the fact that the project is a low impact development, no water quality treatment is
required for the site. The pre-development and post development peak flow comparison is the following:

The stage/storage calculations are included in Appendix A of this report. The rainfall intensities used are
for the 24 hour storm for each storm event for both the pre-developed and post-developed conditions
based on the latest rainfall data from NOAA.

Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

6.0 Outlet Structures

The outlet structure will be constructed within the BMP near the downstream end of the pond. The
structure has been designed to efficiently provide control of the peak rate of discharge. An emergency
spillway has been included into the design to pass the 50 & 100 year storm events with at least 0.5’ of
freeboard.

7.0 Stormwater System

Stormwater conveyances to the BMP forebay will be through overland flow and a closed stormwater
drainage pipe network. The pipe network calculations are based on the future build out of the site and
were sized for a 10-year storm frequency. All proposed catch basins have be sized based on a flow of 4-
incehs per hour to effectively analyze gutter spread within the subdivision. The calculations have been
provided in Appendix B.

8.0 Erosion Control

Erosion control will be provided by utilizing construction entrance, perimeter silt fence, diversion
ditches, check dams, and a temporary skimmer basins (with Faircloth Skimmer device). Phase II erosion
control shall also utilize inlet protection until the project area has been adequately stabilized. Erosion
control devices will be maintain in place until approval by the Village of Wesley Chapel Engineering
staff at which time temporary measures will be removed. A copy of the erosion control plan and
sediment basin calculations has been provided in Appendix D.

Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

Appendix A
Stormwater Hydrographs (24-hour: 1-yr, 2-yr, 10-yr, 25-yr, 50-year, and 100-year)
Pre-Development Drainage Area Map
Post-Development Drainage Area Map

6198-CAVESSON
U.S. Fish and Wildlife Service, National Standards and Support Team,[e-mail]
Wetlands
Estuarine and Marine Deepwater
Estuarine and Marine Wetland
Freshwater Emergent Wetland
Freshwater Forested/Shrub Wetland
Freshwater Pond
Lake
Other
Riverine
July 26, 2018
0 0.15 0.30.075 mi
0 0.3 0.60.15 km
1:11,072
This page was produced by the NWI mapperNational Wetlands Inventory (NWI)
This map is for general reference only. The US Fish and Wildlife Service is not responsible for the accuracy or currentness of the base data shown on this map. All wetlands related data should be used in accordance with the layer metadata found on the Wetlands Mapper web site.
0+001+002
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17+0018+0019+0020+0021+0022+0022+910+001+002+00
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1
1
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12+00
12
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3
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ALIGNMENT=TC-PRE-1STATION=5+03.16OFFSET=0.00NORTHING=455213.24EASTING=1498285.22ALIGNMENT=TC-PRE-1STATION=3+00.00OFFSET=0.00NORTHING=455211.89EASTING=1498090.446
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5955
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5805755706
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5955905855805755455505555605655705755805855905956005
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605605600595
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585570570565560555 59
5545
ALIGNMENT=TC-PRE-2STATION=3+26.97OFFSET=0.00NORTHING=456471.15EASTING=1498071.23ALIGNMENT=TC-PRE-2STATION=11+70.07OFFSET=0.00NORTHING=455750.58EASTING=1498390.90ALIGNMENT=TC-PRE-2STATION=15+03.13OFFSET=0.00NORTHING=455667.68EASTING=1498712.71ALIGNMENT=TC-PRE-2STATION=2+59.97OFFSET=0.00NORTHING=456534.73EASTING=1498050.985455500+001+002+003+004+005+006+007+008+009+0010+0011+0012+0013+0014+0015+0015+510040'80'80SheetScale
DESIGNED BY CHECKED BY
JOB NUMBER
DRAWN BY
DATE
NO.DATE BY ISSUE
www.eagleonline.net
P.O. BOX 551
Alpharetta, GA 30009
[phone]
2013A Van Buren Avenue
Indian Trail, NC 28079
[phone]
FIRM LICENSE # C-0873
AS SHOWN 5/25/2018 6198
PRE-DEVELOPMENT
DRAINAGE AREA MAP
CAVESSON
VILLAGE OF WESLEY CHAPEL
BOWMAN DEVELOPMENT
13815 CINNABAR PL
HUNTERSVILLE, NC
JHRKEWKEWPRE-DANSWEE.E.I.STUDY POINTPRE-DEVELOPMENT AREA 2AREA = 27.92 ACCN = 70Tc = 32.1 minEXISTING FLOOD PLAINSHEET FLOWSHALLOWCONCENTRATEDFLOWC
H
A
N
N
E
L

F
L
OWCHANNEL FLOW ALONG REACHCHAMBWOOD ROADCHAMBWOOD ROADPRE-DEVELOPMENT AREA 1AREA = 25.33 ACCN = 75Tc = 42 minC
H
A
N
N
E
L

F
L
OW
EXISTING POND LENGTHNOT INCLUDED IN TcCALCULATIONSSHALLOWCONCENTRATEDFLOWSHEET FLOWCHANNEL FLOWCHANNEL FLOW EXISTINGPONDEXISTINGPONDEXISTINGPONDCHANNEL FLOW ALONG REACHCHANNEL FLOW ALONG REACHEND PRE-1 TcEND PRE-2 Tc
OPEN SPACE
71,807 sq ft
1.65 ac
LOT : 20
43,137 sq ft
0.99 ac
LOT : 27
40,130 sq ft
0.92 ac
OPEN SPACE : 107
8,546 sq ft
0.20 ac
OPEN SPACE : 120
9,596 sq ft
0.22 ac
OPEN SPACE
391,321 sq ft
8.98 ac
LOT : 19
45,589 sq ft
1.05 ac
LOT : 21
40,291 sq ft
0.92 ac
LOT : 26
41,930 sq ft
0.96 ac
LOT : 22
48,262 sq ft
1.11 ac
LOT : 23
40,248 sq ft
0.92 ac
LOT : 25
41,071 sq ft
0.94 ac
LOT : 24
41,998 sq ft
0.96 ac
LOT : 28
43,358 sq ft
1.00 ac
LOT : 16
40,240 sq ft
0.92 ac
LOT : 17
40,071 sq ft
0.92 ac
LOT : 18
40,073 sq ft
0.92 ac
LOT : 14
40,569 sq ft
0.93 ac
LOT : 15
40,040 sq ft
0.92 ac
LOT : 13
40,708 sq ft
0.93 ac
LOT : 12
50,858 sq ft
1.17 ac
LOT : 3
40,422 sq ft
0.93 ac
LOT : 11
41,000 sq ft
0.94 ac
LOT : 2
41,374 sq ft
0.95 ac
LOT : 10
40,987 sq ft
0.94 ac
LOT : 1
43,441 sq ft
1.00 ac
LOT : 9
40,974 sq ft
0.94 ac
LOT : 8
40,961 sq ft
0.94 ac
LOT : 7
40,948 sq ft
0.94 ac
LOT : 6
56,352 sq ft
1.29 ac
LOT : 4
43,306 sq ft
0.99 ac
LOT : 5
59,984 sq ft
1.38 ac
D600
590
580
570600610
600590
58
0
55
0
560
570
58
0
59
0
600 580590600 6006005905
7
0
5
7
0
560
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1
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2
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3
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4+00
5+006+007+008+009+0010+0011+0012+0013+0014+0015+0016+0017+0018+0019+0020+0021+00
22+00
23+0024+0025+0026+0027+0028+0029+0030+00
3
1
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32
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33
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034+0035+0035+15ALIGNMENT=TC-POST-BYPASS
STATION=1+00.00
OFFSET=0.00
NORTHING=456260.43
EASTING=1498419.37
ALIGNMENT=TC-POST-BYPASS
STATION=3+69.55
OFFSET=0.00
NORTHING=456130.63
EASTING=1498186.55
5505
6
4
.
4
9
5
64
.
8
5
5
6
7
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6
6
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1
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1
1
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74
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Sheet ScaleDESIGNED BYCHECKED BYJOB NUMBERDRAWN BYDATENO.DATEBYISSUEwww.eagleonline.net P.O. BOX 551Alpharetta, GA 30009(678) 339-06402013A Van Buren AvenueIndian Trail, NC 28079(704) 882-4222FIRM LICENSE # C-0873AS SHOWN6198CAVESSONVILLAGE OF WESLEY CHAPELBOWMAN DEVELOPMENT13815 CINNABAR PLHUNTERSVILLE, NCJHRNSWEE.E
.
I
.DRAINAGE AREA MAPPOST DEVELOPMENTKEWKEW5/25/2018POST-DA
STUDY POINT
POST DEVELOPMENT AREA
AREA = 27.15 AC
CN = 73
Tc = 5 min
00 40'80'
80
EXISTING FLOOD PLAIN
CHAMBWOO
D

R
O
A
D
CHAMBWOO
D

R
O
A
D
POST DEVELOPMENT BYPASS 1
AREA = 26.15 AC
CN = 78
Tc = 29.6 min
EXISTING POND LENGTH
NOT INCLUDED IN Tc
CALCULATIONS
EXISTING
POND
POST DEVELOPMENT BYPASS 2
AREA = 0.32 AC
CN = 61
Tc = 5 min
(SAME PRE VS. POST)17-20-18KEWREVISED DRAINAGE AREAS PER TOWN 1st REVIEW COMMENTSS
H
E
E
T
FL
O
W
S
H
A
L
L
OW
C
O
N
C
E
N
T
R
A
T
E
D
F
L
OW
CHANNEL FLOWCHANNEL FLOWCHANNEL FLOW
EXISTING
POND
EXISTING
POND
Hydraflow Table of Contents 6198-PRE-POST - Wet Pond.gpw
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Watershed Model Schematic..................................................................................... 1
Hydrograph Return Period Recap............................................................................. 2
1 - Year
Summary Report......................................................................................................................... 3
Hydrograph Reports................................................................................................................... 4
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1............................................ 4
TR-55 Tc Worksheet............................................................................................................ 5
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT................................. 6
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2............................................ 7
TR-55 Tc Worksheet............................................................................................................ 8
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT................................ 9
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 10
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 11
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 12
Pond Report - WET POND................................................................................................ 13
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 14
TR-55 Tc Worksheet.......................................................................................................... 15
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 16
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 17
2 - Year
Summary Report....................................................................................................................... 18
Hydrograph Reports................................................................................................................. 19
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1.......................................... 19
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT............................... 20
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2.......................................... 21
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT.............................. 22
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 23
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 24
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 25
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 26
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 27
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 28
10 - Year
Summary Report....................................................................................................................... 29
Hydrograph Reports................................................................................................................. 30
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1.......................................... 30
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT............................... 31
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2.......................................... 32
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT.............................. 33
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 34
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 35
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 36
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 37
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 38
Contents continued...6198-PRE-POST - Wet Pond.gpw
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 39
25 - Year
Summary Report....................................................................................................................... 40
Hydrograph Reports................................................................................................................. 41
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1.......................................... 41
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT............................... 42
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2.......................................... 43
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT.............................. 44
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 45
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 46
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 47
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 48
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 49
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 50
50 - Year
Summary Report....................................................................................................................... 51
Hydrograph Reports................................................................................................................. 52
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1.......................................... 52
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT............................... 53
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2.......................................... 54
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT.............................. 55
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 56
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 57
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 58
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 59
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 60
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 61
100 - Year
Summary Report....................................................................................................................... 62
Hydrograph Reports................................................................................................................. 63
Hydrograph No. 1, SCS Runoff, PRE-DEVELOPMENT AREA 1.......................................... 63
Hydrograph No. 2, Reach, PRE 1 - CONVEYANCE TO STUDY POINT............................... 64
Hydrograph No. 3, SCS Runoff, PRE-DEVELOPMENT AREA 2.......................................... 65
Hydrograph No. 4, Reach, PRE-2 - CONVEYANCE TO STUDY POINT.............................. 66
Hydrograph No. 6, Combine, TOTAL PRE DISCHARGE...................................................... 67
Hydrograph No. 8, SCS Runoff, POST DEVELOPMENT AREA........................................... 68
Hydrograph No. 9, Reservoir, DRY POND DISCHARGE...................................................... 69
Hydrograph No. 10, SCS Runoff, POST BYPASS 1.............................................................. 70
Hydrograph No. 11, Reach, PRE-2 - CONVEYANCE TO STUDY POINT............................ 71
Hydrograph No. 13, Combine, TOTAL POST DISCHARGE.................................................. 72
IDF Report.................................................................................................................. 73
1
2
3
4
6
8
9
10
11
13
1
Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Project: 6198-PRE-POST - Wet Pond.gpw Wednesday, 09 / 12 / 2018
Hyd.Origin Description
Legend
1 SCS Runoff PRE-DEVELOPMENT AREA 1
2 Reach PRE 1 - CONVEYANCE TO STUDY POINT
3 SCS Runoff PRE-DEVELOPMENT AREA 2
4 Reach PRE-2 - CONVEYANCE TO STUDY POINT
6 Combine TOTAL PRE DISCHARGE
8 SCS Runoff POST DEVELOPMENT AREA
9 Reservoir DRY POND DISCHARGE
10 SCS Runoff POST BYPASS 1
11 Reach PRE-2 - CONVEYANCE TO STUDY POINT
13 Combine TOTAL POST DISCHARGE
Hydrograph Return Period Recap
2
Hyd. Hydrograph Inflow Peak Outflow (cfs) Hydrograph
No. type hyd(s)Description
(origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr
1 SCS Runoff ------ 15.34 23.16 ------- ------- 46.84 62.37 75.29 88.96 PRE-DEVELOPMENT AREA 1
2 Reach 1 10.75 16.86 ------- ------- 36.26 49.41 60.49 72.28 PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff ------ 13.63 22.57 ------- ------- 50.91 70.09 86.29 103.60 PRE-DEVELOPMENT AREA 2
4 Reach 3 6.454 11.48 ------- ------- 29.29 42.18 53.36 65.53 PRE-2 - CONVEYANCE TO STUDY
6 Combine 2, 4, 17.20 28.33 ------- ------- 65.50 91.47 113.78 137.70 TOTAL PRE DISCHARGE
8 SCS Runoff ------ 37.78 56.33 ------- ------- 112.04 149.47 180.67 213.44 POST DEVELOPMENT AREA
9 Reservoir 8 1.714 4.834 ------- ------- 16.41 23.03 27.35 40.66 DRY POND DISCHARGE
10 SCS Runoff ------ 24.96 35.96 ------- ------- 68.59 89.65 107.01 125.15 POST BYPASS 1
11 Reach 10 12.32 18.87 ------- ------- 39.60 53.58 65.45 78.07 PRE-2 - CONVEYANCE TO STUDY
13 Combine 9, 11, 13.28 23.70 ------- ------- 55.25 75.76 91.95 109.04 TOTAL POST DISCHARGE
Proj. file: 6198-PRE-POST - Wet Pond.gpw Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Summary Report
3
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 15.34 2 740 86,170 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 10.75 2 762 86,156 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 13.63 2 734 70,464 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 6.454 2 760 70,438 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 17.20 2 762 156,593 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 37.78 2 718 76,389 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 1.714 2 824 73,410 8 546.28 39,145 DRY POND DISCHARGE
10 SCS Runoff 24.96 2 732 103,787 ------ ------ ------ POST BYPASS 1
11 Reach 12.32 2 752 103,764 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 13.28 2 754 177,174 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 1 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 15.34 cfs
Storm frequency = 1 yrs Time to peak = 12.33 hrs
Time interval = 2 min Hyd. volume = 86,170 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 2.95 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
4
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
3.00 3.00
6.00 6.00
9.00 9.00
12.00 12.00
15.00 15.00
18.00 18.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 1 Year
Hyd No. 1
TR55 Tc Worksheet 5
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Description A B C Totals
Sheet Flow
Manning's n-value = 0.240 0.011 0.011
Flow length (ft) = 300.0 0.0 0.0
Two-year 24-hr precip. (in) = 3.56 0.00 0.00
Land slope (%) = 4.09 0.00 0.00
Travel Time (min) = 24.47 + 0.00 + 0.00 = 24.47
Shallow Concentrated Flow
Flow length (ft) = 203.16 0.00 0.00
Watercourse slope (%) = 5.85 0.00 0.00
Surface description = Unpaved Paved Paved
Average velocity (ft/s) =3.90 0.00 0.00
Travel Time (min) = 0.87 + 0.00 + 0.00 = 0.87
Channel Flow
X sectional flow area (sqft) = 5.45 0.00 0.00
Wetted perimeter (ft) = 12.54 0.00 0.00
Channel slope (%) = 4.30 0.00 0.00
Manning's n-value = 0.240 0.015 0.015
Velocity (ft/s) =0.74
0.00
0.00
Flow length (ft) ({0})735.2 0.0 0.0
Travel Time (min) = 16.64 + 0.00 + 0.00 = 16.64
Total Travel Time, Tc ..............................................................................42.00 min
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 10.75 cfs
Storm frequency = 1 yrs Time to peak = 12.70 hrs
Time interval = 2 min Hyd. volume = 86,156 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.44 ft/s Routing coeff. = 0.0793
Modified Att-Kin routing method used.
6
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
3.00 3.00
6.00 6.00
9.00 9.00
12.00 12.00
15.00 15.00
18.00 18.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 1 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 13.63 cfs
Storm frequency = 1 yrs Time to peak = 12.23 hrs
Time interval = 2 min Hyd. volume = 70,464 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 2.95 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
7
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
2.00 2.00
4.00 4.00
6.00 6.00
8.00 8.00
10.00 10.00
12.00 12.00
14.00 14.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 1 Year
Hyd No. 3
TR55 Tc Worksheet 8
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Description A B C Totals
Sheet Flow
Manning's n-value = 0.240 0.011 0.011
Flow length (ft) = 260.0 0.0 0.0
Two-year 24-hr precip. (in) = 3.56 0.00 0.00
Land slope (%) = 5.58 0.00 0.00
Travel Time (min) = 19.27 + 0.00 + 0.00 = 19.27
Shallow Concentrated Flow
Flow length (ft) = 67.00 0.00 0.00
Watercourse slope (%) = 6.33 0.00 0.00
Surface description = Unpaved Paved Paved
Average velocity (ft/s) =4.06 0.00 0.00
Travel Time (min) = 0.28 + 0.00 + 0.00 = 0.28
Channel Flow
X sectional flow area (sqft) = 24.03 0.00 0.00
Wetted perimeter (ft) = 13.88 0.00 0.00
Channel slope (%) = 5.79 0.00 0.00
Manning's n-value = 0.240 0.015 0.015
Velocity (ft/s) =2.16
0.00
0.00
Flow length (ft) ({0})1630.7 0.0 0.0
Travel Time (min) = 12.60 + 0.00 + 0.00 = 12.60
Total Travel Time, Tc ..............................................................................32.10 min
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 6.454 cfs
Storm frequency = 1 yrs Time to peak = 12.67 hrs
Time interval = 2 min Hyd. volume = 70,438 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.43 ft/s Routing coeff. = 0.0439
Modified Att-Kin routing method used.
9
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
2.00 2.00
4.00 4.00
6.00 6.00
8.00 8.00
10.00 10.00
12.00 12.00
14.00 14.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 1 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 17.20 cfs
Storm frequency = 1 yrs Time to peak = 12.70 hrs
Time interval = 2 min Hyd. volume = 156,593 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
10
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
3.00 3.00
6.00 6.00
9.00 9.00
12.00 12.00
15.00 15.00
18.00 18.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 1 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 37.78 cfs
Storm frequency = 1 yrs Time to peak = 11.97 hrs
Time interval = 2 min Hyd. volume = 76,389 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 2.95 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
11
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 1 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 1.714 cfs
Storm frequency = 1 yrs Time to peak = 13.73 hrs
Time interval = 2 min Hyd. volume = 73,410 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 546.28 ft
Reservoir name = WET POND Max. Storage = 39,145 cuft
Storage Indication method used.
12
0 10 20 30 40 50 60 70 80 90 100
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 1 Year
Hyd No. 9 Hyd No. 8 Total storage used = 39,145 cuft
Pond Report 13
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Pond No. 1 - WET POND
Pond Data
Contours -User-defined contour areas. Average end area method used for volume calculation. Begining Elevation = 545.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cuft) Total storage (cuft)
0.00 545.00 28,325 0 0
1.00 546.00 30,944 29,635 29,635
2.00 547.00 36,385 33,665 63,299
3.00 548.00 39,206 37,796 101,095
4.00 549.00 42,094 40,650 141,745
5.00 550.00 45,050 43,572 185,317
6.00 551.00 48,073 46,562 231,878
Culvert / Orifice Structures Weir Structures
[A] [B] [C] [PrfRsr] [A] [B] [C] [D]
Rise (in)= 24.00 3.00 0.00 0.00
Span (in)= 24.00 3.00 0.00 0.00
No. Barrels = 1 100
Invert El. (ft)= 545.00 545.00 0.00 0.00
Length (ft)= 72.00 0.00 0.00 0.00
Slope (%)= 0.63 0.00 0.00 n/a
N-Value = .013 .013 .013 n/a
Orifice Coeff.= 0.60 0.60 0.60 0.60
Multi-Stage = n/a Yes No No
Crest Len (ft)= 13.00 3.00 Inactive 20.00
Crest El. (ft)= 549.50 546.00 546.00 550.00
Weir Coeff.= 3.33 3.33 3.33 3.33
Weir Type = 1 Rect Rect Ciplti
Multi-Stage = Yes Yes Yes No
Exfil.(in/hr)= 0.000 (by Contour)
TW Elev. (ft)= 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage / Storage / Discharge Table
Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total
ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs
0.00 0 545.00 0.00 0.00 --- --- 0.00 0.00 0.00 0.00 --- --- 0.000
1.00 29,635 546.00 0.22 ic 0.21 ic --- --- 0.00 0.00 0.00 0.00 --- --- 0.214
2.00 63,299 547.00 8.92 oc 0.18 ic --- --- 0.00 8.74 s 0.00 0.00 --- --- 8.920
3.00 101,095 548.00 17.01 oc 0.14 ic --- --- 0.00 16.87 s 0.00 0.00 --- --- 17.01
4.00 141,745 549.00 24.08 oc 0.12 ic --- --- 0.00 23.96 s 0.00 0.00 --- --- 24.08
5.00 185,317 550.00 29.93 ic 0.07 ic --- --- 8.83 s 21.02 s 0.00 0.00 --- --- 29.92
6.00 231,878 551.00 33.75 ic 0.03 ic --- --- 17.87 s 15.80 s 0.00 66.60 --- --- 100.31
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 24.96 cfs
Storm frequency = 1 yrs Time to peak = 12.20 hrs
Time interval = 2 min Hyd. volume = 103,787 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 2.95 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
14
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
28.00 28.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 1 Year
Hyd No. 10
TR55 Tc Worksheet 15
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hyd. No. 10
POST BYPASS 1
Description A B C Totals
Sheet Flow
Manning's n-value = 0.240 0.011 0.011
Flow length (ft) = 260.0 0.0 0.0
Two-year 24-hr precip. (in) = 3.56 0.00 0.00
Land slope (%) = 5.58 0.00 0.00
Travel Time (min) = 19.27 + 0.00 + 0.00 = 19.27
Shallow Concentrated Flow
Flow length (ft) = 67.00 0.00 0.00
Watercourse slope (%) = 6.33 0.00 0.00
Surface description = Unpaved Paved Paved
Average velocity (ft/s) =4.06 0.00 0.00
Travel Time (min) = 0.28 + 0.00 + 0.00 = 0.28
Channel Flow
X sectional flow area (sqft) = 24.03 0.00 0.00
Wetted perimeter (ft) = 13.88 0.00 0.00
Channel slope (%) = 5.79 0.00 0.00
Manning's n-value = 0.240 0.015 0.015
Velocity (ft/s) =2.16
0.00
0.00
Flow length (ft) ({0})1303.6 0.0 0.0
Travel Time (min) = 10.07 + 0.00 + 0.00 = 10.07
Total Travel Time, Tc ..............................................................................29.60 min
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 12.32 cfs
Storm frequency = 1 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 103,764 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.50 ft/s Routing coeff. = 0.0513
Modified Att-Kin routing method used.
16
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
28.00 28.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 1 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 13.28 cfs
Storm frequency = 1 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 177,174 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
17
0 6 12 18 24 30 36 42 48 54
Q (cfs)
0.00 0.00
2.00 2.00
4.00 4.00
6.00 6.00
8.00 8.00
10.00 10.00
12.00 12.00
14.00 14.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 1 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydrograph Summary Report
18
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 23.16 2 740 124,807 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 16.86 2 760 124,794 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 22.57 2 734 107,269 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 11.48 2 758 107,246 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 28.33 2 758 232,040 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 56.33 2 718 112,734 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 4.834 2 752 109,721 8 546.60 49,834 DRY POND DISCHARGE
10 SCS Runoff 35.96 2 732 146,480 ------ ------ ------ POST BYPASS 1
11 Reach 18.87 2 750 146,459 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 23.70 2 750 256,180 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 2 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 23.16 cfs
Storm frequency = 2 yrs Time to peak = 12.33 hrs
Time interval = 2 min Hyd. volume = 124,807 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 3.56 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
19
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 2 Year
Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 16.86 cfs
Storm frequency = 2 yrs Time to peak = 12.67 hrs
Time interval = 2 min Hyd. volume = 124,794 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.49 ft/s Routing coeff. = 0.0880
Modified Att-Kin routing method used.
20
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 2 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 22.57 cfs
Storm frequency = 2 yrs Time to peak = 12.23 hrs
Time interval = 2 min Hyd. volume = 107,269 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 3.56 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
21
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 2 Year
Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 11.48 cfs
Storm frequency = 2 yrs Time to peak = 12.63 hrs
Time interval = 2 min Hyd. volume = 107,246 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.49 ft/s Routing coeff. = 0.0500
Modified Att-Kin routing method used.
22
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 2 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 28.33 cfs
Storm frequency = 2 yrs Time to peak = 12.63 hrs
Time interval = 2 min Hyd. volume = 232,040 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
23
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
5.00 5.00
10.00 10.00
15.00 15.00
20.00 20.00
25.00 25.00
30.00 30.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 2 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 56.33 cfs
Storm frequency = 2 yrs Time to peak = 11.97 hrs
Time interval = 2 min Hyd. volume = 112,734 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 3.56 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
24
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 2 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 4.834 cfs
Storm frequency = 2 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 109,721 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 546.60 ft
Reservoir name = WET POND Max. Storage = 49,834 cuft
Storage Indication method used.
25
0 8 16 24 32 40 48 56 64 72 80
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 2 Year
Hyd No. 9 Hyd No. 8 Total storage used = 49,834 cuft
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 35.96 cfs
Storm frequency = 2 yrs Time to peak = 12.20 hrs
Time interval = 2 min Hyd. volume = 146,480 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 3.56 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
26
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 2 Year
Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 18.87 cfs
Storm frequency = 2 yrs Time to peak = 12.50 hrs
Time interval = 2 min Hyd. volume = 146,459 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.55 ft/s Routing coeff. = 0.0564
Modified Att-Kin routing method used.
27
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 2 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 23.70 cfs
Storm frequency = 2 yrs Time to peak = 12.50 hrs
Time interval = 2 min Hyd. volume = 256,180 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
28
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28
Q (cfs)
0.00 0.00
4.00 4.00
8.00 8.00
12.00 12.00
16.00 16.00
20.00 20.00
24.00 24.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 2 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydrograph Summary Report
29
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 46.84 2 740 243,279 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 36.26 2 756 243,269 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 50.91 2 734 225,073 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 29.29 2 754 225,055 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 65.50 2 754 468,323 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 112.04 2 718 226,023 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 16.41 2 728 222,950 8 547.93 98,435 DRY POND DISCHARGE
10 SCS Runoff 68.59 2 730 274,414 ------ ------ ------ POST BYPASS 1
11 Reach 39.60 2 748 274,396 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 55.25 2 748 497,345 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 10 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 46.84 cfs
Storm frequency = 10 yrs Time to peak = 12.33 hrs
Time interval = 2 min Hyd. volume = 243,279 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 5.21 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
30
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 10 Year
Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 36.26 cfs
Storm frequency = 10 yrs Time to peak = 12.60 hrs
Time interval = 2 min Hyd. volume = 243,269 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.59 ft/s Routing coeff. = 0.1051
Modified Att-Kin routing method used.
31
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 10 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 50.91 cfs
Storm frequency = 10 yrs Time to peak = 12.23 hrs
Time interval = 2 min Hyd. volume = 225,073 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 5.21 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
32
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 10 Year
Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 29.29 cfs
Storm frequency = 10 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 225,055 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.61 ft/s Routing coeff. = 0.0617
Modified Att-Kin routing method used.
33
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 10 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 65.50 cfs
Storm frequency = 10 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 468,323 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
34
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 10 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 112.04 cfs
Storm frequency = 10 yrs Time to peak = 11.97 hrs
Time interval = 2 min Hyd. volume = 226,023 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 5.21 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
35
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 10 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 16.41 cfs
Storm frequency = 10 yrs Time to peak = 12.13 hrs
Time interval = 2 min Hyd. volume = 222,950 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 547.93 ft
Reservoir name = WET POND Max. Storage = 98,435 cuft
Storage Indication method used.
36
0 4 8 12 16 20 24 28 32 36 40 44
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 10 Year
Hyd No. 9 Hyd No. 8 Total storage used = 98,435 cuft
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 68.59 cfs
Storm frequency = 10 yrs Time to peak = 12.17 hrs
Time interval = 2 min Hyd. volume = 274,414 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 5.21 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
37
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 10 Year
Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 39.60 cfs
Storm frequency = 10 yrs Time to peak = 12.47 hrs
Time interval = 2 min Hyd. volume = 274,396 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.65 ft/s Routing coeff. = 0.0666
Modified Att-Kin routing method used.
38
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 10 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 55.25 cfs
Storm frequency = 10 yrs Time to peak = 12.47 hrs
Time interval = 2 min Hyd. volume = 497,345 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
39
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 10 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydrograph Summary Report
40
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 62.37 2 740 322,156 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 49.41 2 754 322,146 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 70.09 2 734 305,877 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 42.18 2 752 305,859 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 91.47 2 754 628,006 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 149.47 2 716 302,316 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 23.03 2 728 299,222 8 548.83 134,847 DRY POND DISCHARGE
10 SCS Runoff 89.65 2 730 358,236 ------ ------ ------ POST BYPASS 1
11 Reach 53.58 2 748 358,219 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 75.76 2 746 657,441 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 25 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 62.37 cfs
Storm frequency = 25 yrs Time to peak = 12.33 hrs
Time interval = 2 min Hyd. volume = 322,156 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 6.22 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
41
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 25 Year
Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 49.41 cfs
Storm frequency = 25 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 322,146 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.64 ft/s Routing coeff. = 0.1129
Modified Att-Kin routing method used.
42
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 25 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 70.09 cfs
Storm frequency = 25 yrs Time to peak = 12.23 hrs
Time interval = 2 min Hyd. volume = 305,877 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 6.22 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
43
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 25 Year
Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 42.18 cfs
Storm frequency = 25 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 305,859 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.66 ft/s Routing coeff. = 0.0669
Modified Att-Kin routing method used.
44
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 25 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 91.47 cfs
Storm frequency = 25 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 628,006 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
45
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
100.00 100.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 25 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 149.47 cfs
Storm frequency = 25 yrs Time to peak = 11.93 hrs
Time interval = 2 min Hyd. volume = 302,316 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 6.22 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
46
0 2 4 6 8 10 12 14 16 18 20 22 24
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
140.00 140.00
160.00 160.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 25 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 23.03 cfs
Storm frequency = 25 yrs Time to peak = 12.13 hrs
Time interval = 2 min Hyd. volume = 299,222 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 548.83 ft
Reservoir name = WET POND Max. Storage = 134,847 cuft
Storage Indication method used.
47
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
140.00 140.00
160.00 160.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 25 Year
Hyd No. 9 Hyd No. 8 Total storage used = 134,847 cuft
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 89.65 cfs
Storm frequency = 25 yrs Time to peak = 12.17 hrs
Time interval = 2 min Hyd. volume = 358,236 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 6.22 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
48
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 25 Year
Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 53.58 cfs
Storm frequency = 25 yrs Time to peak = 12.47 hrs
Time interval = 2 min Hyd. volume = 358,219 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.70 ft/s Routing coeff. = 0.0713
Modified Att-Kin routing method used.
49
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 25 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 75.76 cfs
Storm frequency = 25 yrs Time to peak = 12.43 hrs
Time interval = 2 min Hyd. volume = 657,441 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
50
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 25 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydrograph Summary Report
51
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 75.29 2 738 388,473 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 60.49 2 754 388,464 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 86.29 2 734 374,721 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 53.36 2 752 374,704 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 113.78 2 752 763,168 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 180.67 2 716 366,788 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 27.35 2 728 363,679 8 549.57 166,506 DRY POND DISCHARGE
10 SCS Runoff 107.01 2 730 428,216 ------ ------ ------ POST BYPASS 1
11 Reach 65.45 2 746 428,200 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 91.95 2 746 791,879 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 50 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 75.29 cfs
Storm frequency = 50 yrs Time to peak = 12.30 hrs
Time interval = 2 min Hyd. volume = 388,473 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 7.04 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
52
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 50 Year
Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 60.49 cfs
Storm frequency = 50 yrs Time to peak = 12.57 hrs
Time interval = 2 min Hyd. volume = 388,464 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.67 ft/s Routing coeff. = 0.1183
Modified Att-Kin routing method used.
53
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 50 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 86.29 cfs
Storm frequency = 50 yrs Time to peak = 12.23 hrs
Time interval = 2 min Hyd. volume = 374,721 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 7.04 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
54
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 50 Year
Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 53.36 cfs
Storm frequency = 50 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 374,704 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.70 ft/s Routing coeff. = 0.0706
Modified Att-Kin routing method used.
55
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 50 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 113.78 cfs
Storm frequency = 50 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 763,168 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
56
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 50 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 180.67 cfs
Storm frequency = 50 yrs Time to peak = 11.93 hrs
Time interval = 2 min Hyd. volume = 366,788 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 7.04 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
57
0 2 4 6 8 10 12 14 16 18 20 22 24
Q (cfs)
0.00 0.00
30.00 30.00
60.00 60.00
90.00 90.00
120.00 120.00
150.00 150.00
180.00 180.00
210.00 210.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 50 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 27.35 cfs
Storm frequency = 50 yrs Time to peak = 12.13 hrs
Time interval = 2 min Hyd. volume = 363,679 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 549.57 ft
Reservoir name = WET POND Max. Storage = 166,506 cuft
Storage Indication method used.
58
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28
Q (cfs)
0.00 0.00
30.00 30.00
60.00 60.00
90.00 90.00
120.00 120.00
150.00 150.00
180.00 180.00
210.00 210.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 50 Year
Hyd No. 9 Hyd No. 8 Total storage used = 166,506 cuft
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 107.01 cfs
Storm frequency = 50 yrs Time to peak = 12.17 hrs
Time interval = 2 min Hyd. volume = 428,216 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 7.04 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
59
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 50 Year
Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 65.45 cfs
Storm frequency = 50 yrs Time to peak = 12.43 hrs
Time interval = 2 min Hyd. volume = 428,200 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.74 ft/s Routing coeff. = 0.0745
Modified Att-Kin routing method used.
60
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 50 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 91.95 cfs
Storm frequency = 50 yrs Time to peak = 12.43 hrs
Time interval = 2 min Hyd. volume = 791,879 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
61
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
100.00 100.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 50 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydrograph Summary Report
62
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval Peak volume hyd(s) elevation strge used Description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1 SCS Runoff 88.96 2 738 458,824 ------ ------ ------ PRE-DEVELOPMENT AREA 1
2 Reach 72.28 2 752 458,815 1 ------ ------ PRE 1 - CONVEYANCE TO STUDY
3 SCS Runoff 103.60 2 732 448,424 ------ ------ ------ PRE-DEVELOPMENT AREA 2
4 Reach 65.53 2 750 448,408 3 ------ ------ PRE-2 - CONVEYANCE TO STUDY
6 Combine 137.70 2 752 907,223 2, 4, ------ ------ TOTAL PRE DISCHARGE
8 SCS Runoff 213.44 2 716 435,419 ------ ------ ------ POST DEVELOPMENT AREA
9 Reservoir 40.66 2 726 432,299 8 550.28 198,039 DRY POND DISCHARGE
10 SCS Runoff 125.15 2 730 502,097 ------ ------ ------ POST BYPASS 1
11 Reach 78.07 2 746 502,082 10 ------ ------ PRE-2 - CONVEYANCE TO STUDY
13 Combine 109.04 2 744 934,381 9, 11, ------ ------ TOTAL POST DISCHARGE
6198-PRE-POST - Wet Pond.gpw Return Period: 100 Year Wednesday, 09 / 12 / 2018
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 1
PRE-DEVELOPMENT AREA 1
Hydrograph type = SCS Runoff Peak discharge = 88.96 cfs
Storm frequency = 100 yrs Time to peak = 12.30 hrs
Time interval = 2 min Hyd. volume = 458,824 cuft
Drainage area = 25.330 ac Curve number = 75*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 42.00 min
Total precip. = 7.89 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.200 x 61) + (18.480 x 74) + (5.650 x 81)] / 25.330
63
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 1
Hyd. No. 1 -- 100 Year
Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 2
PRE 1 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 72.28 cfs
Storm frequency = 100 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 458,815 cuft
Inflow hyd. No. = 1 - PRE-DEVELOPMENT AREA 1Section type = Trapezoidal
Reach length = 870.2 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.70 ft/s Routing coeff. = 0.1234
Modified Att-Kin routing method used.
64
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
10.00 10.00
20.00 20.00
30.00 30.00
40.00 40.00
50.00 50.00
60.00 60.00
70.00 70.00
80.00 80.00
90.00 90.00
Q (cfs)
Time (hrs)
PRE 1 - CONVEYANCE TO STUDY POINT
Hyd. No. 2 -- 100 Year
Hyd No. 2 Hyd No. 1
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 3
PRE-DEVELOPMENT AREA 2
Hydrograph type = SCS Runoff Peak discharge = 103.60 cfs
Storm frequency = 100 yrs Time to peak = 12.20 hrs
Time interval = 2 min Hyd. volume = 448,424 cuft
Drainage area = 27.920 ac Curve number = 70*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 32.10 min
Total precip. = 7.89 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(11.380 x 61) + (13.140 x 74) + (3.400 x 84)] / 27.920
65
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
PRE-DEVELOPMENT AREA 2
Hyd. No. 3 -- 100 Year
Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 4
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 65.53 cfs
Storm frequency = 100 yrs Time to peak = 12.50 hrs
Time interval = 2 min Hyd. volume = 448,408 cuft
Inflow hyd. No. = 3 - PRE-DEVELOPMENT AREA 2Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.73 ft/s Routing coeff. = 0.0739
Modified Att-Kin routing method used.
66
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 4 -- 100 Year
Hyd No. 4 Hyd No. 3
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 6
TOTAL PRE DISCHARGE
Hydrograph type = Combine Peak discharge = 137.70 cfs
Storm frequency = 100 yrs Time to peak = 12.53 hrs
Time interval = 2 min Hyd. volume = 907,223 cuft
Inflow hyds. = 2, 4 Contrib. drain. area = 0.000 ac
67
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
140.00 140.00
Q (cfs)
Time (hrs)
TOTAL PRE DISCHARGE
Hyd. No. 6 -- 100 Year
Hyd No. 6 Hyd No. 2 Hyd No. 4
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 8
POST DEVELOPMENT AREA
Hydrograph type = SCS Runoff Peak discharge = 213.44 cfs
Storm frequency = 100 yrs Time to peak = 11.93 hrs
Time interval = 2 min Hyd. volume = 435,419 cuft
Drainage area = 27.150 ac Curve number = 73*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = User Time of conc. (Tc) = 5.00 min
Total precip. = 7.89 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(10.770 x 68) + (16.380 x 77)] / 27.150
68
0 2 4 6 8 10 12 14 16 18 20 22 24
Q (cfs)
0.00 0.00
30.00 30.00
60.00 60.00
90.00 90.00
120.00 120.00
150.00 150.00
180.00 180.00
210.00 210.00
240.00 240.00
Q (cfs)
Time (hrs)
POST DEVELOPMENT AREA
Hyd. No. 8 -- 100 Year
Hyd No. 8
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 9
DRY POND DISCHARGE
Hydrograph type = Reservoir Peak discharge = 40.66 cfs
Storm frequency = 100 yrs Time to peak = 12.10 hrs
Time interval = 2 min Hyd. volume = 432,299 cuft
Inflow hyd. No. = 8 - POST DEVELOPMENT AREAMax. Elevation = 550.28 ft
Reservoir name = WET POND Max. Storage = 198,039 cuft
Storage Indication method used.
69
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28
Q (cfs)
0.00 0.00
30.00 30.00
60.00 60.00
90.00 90.00
120.00 120.00
150.00 150.00
180.00 180.00
210.00 210.00
240.00 240.00
Q (cfs)
Time (hrs)
DRY POND DISCHARGE
Hyd. No. 9 -- 100 Year
Hyd No. 9 Hyd No. 8 Total storage used = 198,039 cuft
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 10
POST BYPASS 1
Hydrograph type = SCS Runoff Peak discharge = 125.15 cfs
Storm frequency = 100 yrs Time to peak = 12.17 hrs
Time interval = 2 min Hyd. volume = 502,097 cuft
Drainage area = 26.150 ac Curve number = 78*
Basin Slope = 0.0 % Hydraulic length = 0 ft
Tc method = TR55 Time of conc. (Tc) = 29.60 min
Total precip. = 7.89 in Distribution = Type II
Storm duration = 24 hrs Shape factor = 484
* Composite (Area/CN) = [(1.810 x 68) + (15.340 x 76) + (9.000 x 82)] / 26.150
70
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
140.00 140.00
Q (cfs)
Time (hrs)
POST BYPASS 1
Hyd. No. 10 -- 100 Year
Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 11
PRE-2 - CONVEYANCE TO STUDY POINT
Hydrograph type = Reach Peak discharge = 78.07 cfs
Storm frequency = 100 yrs Time to peak = 12.43 hrs
Time interval = 2 min Hyd. volume = 502,082 cuft
Inflow hyd. No. = 10 - POST BYPASS 1 Section type = Trapezoidal
Reach length = 1551.3 ft Channel slope = 1.5 %
Manning's n = 0.240 Bottom width = 15.0 ft
Side slope = 7.0:1 Max. depth = 4.1 ft
Rating curve x = 0.123 Rating curve m = 1.359
Ave. velocity = 0.77 ft/s Routing coeff. = 0.0776
Modified Att-Kin routing method used.
71
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
140.00 140.00
Q (cfs)
Time (hrs)
PRE-2 - CONVEYANCE TO STUDY POINT
Hyd. No. 11 -- 100 Year
Hyd No. 11 Hyd No. 10
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Hyd. No. 13
TOTAL POST DISCHARGE
Hydrograph type = Combine Peak discharge = 109.04 cfs
Storm frequency = 100 yrs Time to peak = 12.40 hrs
Time interval = 2 min Hyd. volume = 934,381 cuft
Inflow hyds. = 9, 11 Contrib. drain. area = 0.000 ac
72
0 2 4 6 8 10 12 14 16 18 20 22 24 26
Q (cfs)
0.00 0.00
20.00 20.00
40.00 40.00
60.00 60.00
80.00 80.00
100.00 100.00
120.00 120.00
Q (cfs)
Time (hrs)
TOTAL POST DISCHARGE
Hyd. No. 13 -- 100 Year
Hyd No. 13 Hyd No. 9 Hyd No. 11
Hydraflow Rainfall Report 73
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Wednesday, 09 / 12 / 2018
Return Intensity-Duration-Frequency Equation Coefficients (FHA)
Period
(Yrs) B D E (N/A)
1 66.8196 12.9000 0.8963 --------
2 71.1962 12.5000 0.8678 --------
3 0.0000 0.0000 0.0000 --------
5 77.9030 12.9000 0.8403 --------
10 71.8008 12.0000 0.7927 --------
25 66.0145 11.1000 0.7420 --------
50 59.2567 10.1000 0.6965 --------
100 53.8843 9.2000 0.6563 --------
File name: 6198-NOAA.IDF
Intensity = B / (Tc + D)^E
Return Intensity Values (in/hr)
Period
(Yrs)5 min1015202530354045505560
1 5.03 4.04 3.38 2.92 2.57 2.30 2.08 1.91 1.76 1.63 1.52 1.43
2 5.94 4.78 4.01 3.47 3.07 2.75 2.50 2.29 2.12 1.97 1.84 1.73
3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5 6.90 5.61 4.75 4.14 3.67 3.31 3.02 2.78 2.57 2.40 2.25 2.12
10 7.60 6.19 5.27 4.60 4.10 3.71 3.39 3.13 2.91 2.72 2.56 2.42
25 8.40 6.87 5.87 5.15 4.61 4.19 3.85 3.56 3.33 3.12 2.95 2.79
50 8.94 7.33 6.28 5.53 4.97 4.53 4.17 3.88 3.63 3.42 3.23 3.07
100 9.44 7.75 6.66 5.88 5.30 4.85 4.48 4.18 3.92 3.70 3.51 3.34
Tc = time in minutes. Values may exceed 60.
Rainfall Precipitation Table (in)
X:\Land Projects R2\6198 - Chambwood Rd - Wesley Chapel - Bowman\Calculations\Stormwater\6198-NOAA 24hr.pcp
Storm
Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr
SCS 24-hour 2.95 3.56 0.00 4.48 5.21 6.22 7.04 7.89
SCS 6-Hr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Huff-1st 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Huff-4th 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Custom 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

Appendix B
Storm Drain Calculations (Pipes, Catch Basins, HGL, Gutter Spread)

OPEN SPACE71,807 sq ft1.65 acLOT : 2043,137 sq ft0.99 acLOT : 2740,130 sq ft0.92 acOPEN SPACE : 1078,546 sq ft0.20 acOPEN SPACE : 1209,596 sq ft0.22 acOPEN SPACE391,321 sq ft8.98 acLOT : 1945,589 sq ft1.05 acLOT : 2140,291 sq ft0.92 acLOT : 2641,930 sq ft0.96 acLOT : 2248,262 sq ft1.11 acLOT : 2340,248 sq ft0.92 acLOT : 2541,071 sq ft0.94 acLOT : 2441,998 sq ft0.96 acLOT : 2843,358 sq ft1.00 acLOT : 1640,240 sq ft0.92 acLOT : 1740,071 sq ft0.92 acLOT : 1840,073 sq ft0.92 acLOT : 1440,569 sq ft0.93 acLOT : 1540,040 sq ft0.92 acLOT : 1340,708 sq ft0.93 acLOT : 1250,858 sq ft1.17 acLOT : 340,422 sq ft0.93 acLOT : 1141,000 sq ft0.94 acLOT : 241,374 sq ft0.95 acLOT : 1040,987 sq ft0.94 acLOT : 143,441 sq ft1.00 acLOT : 940,974 sq ft0.94 acLOT : 840,961 sq ft0.94 acLOT : 740,948 sq ft0.94 acLOT : 656,352 sq ft1.29 acLOT : 443,306 sq ft0.99 acLOT : 559,984 sq ft1.38 ac5905925
8
0
5
8
4
5
7
0 58058658057256456256657
0
570
58859
1
59
2DCB-1020.39ac.CB-1240.13ac.CB-1250.16ac.CB-1260.18ac.CB-1270.22ac.CB-1300.86ac.DI-1310.50ac.CB-1360.47ac.CB-1030.40ac.CB-1050.27ac.CB-1040.16ac.CB-1370.02ac.CB-1100.50ac.CB-1110.63ac.CB-1380.07ac.CB-1120.53ac.CB-1390.26ac.CB-1161.38ac.CB-1170.08ac.CB-1180.52ac.CB-1410.42ac.CB-1200.07ac.CB-1420.35ac.DI-1431.29ac.CB-1210.15ac.CB-1220.56ac.CB-1230.65ac.DI-1331.65ac.CB-1340.21ac.CB-1320.22ac.CB-1060.27ac.CB-1070.25ac.CB-1090.70ac.CB-1141.00ac.CB-1290.46ac.CB-1280.27ac.CB-1150.59ac.6
0
0
5955
9
0
5
8
5
5805755706
0
0
610605
600
5955905855805755455505555605655705755805855905956005
4
5
5455455455455
7
5
58
0
585
59
0
59
5
6
0
0
600
605605600595
590
585570570565560555 59
5545DI-108A0.63ac.CB-1350.95ac.CB-1080.29ac.CB-109A0.10ac.5465505485455500+001+002+003+004+005+006+007+008+009+0010+0011+0012+0013+0014+0015+0015+51DI-1191.41ac.DI-1440.28ac.DI-112A0.30ac.CB-1130.58ac.DI-1401.04ac.DI-140A2.22ac.-2.9%SheetScale
DESIGNED BY CHECKED BY
JOB NUMBER
DRAWN BY
DATE
NO.DATE BY ISSUE
www.eagleonline.net
P.O. BOX 551
Alpharetta, GA 30009
[phone]
2013A Van Buren Avenue
Indian Trail, NC 28079
[phone]
FIRM LICENSE # C-0873
AS SHOWN 6198
CAVESSON
VILLAGE OF WESLEY CHAPEL
BOWMAN DEVELOPMENT
13815 CINNABAR PL
HUNTERSVILLE, NC
JHRNSWEE.E.I.DRAINAGE AREA MAP
CATCH BASIN
KEW KEW
5/25/2018CB-DASTUDY POINT0040'80'80EXISTING FLOOD PLAINCHAMBWOOD ROADCHAMBWOOD ROAD
Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

Appendix C
Hydrological Soils Map and Summary Report
SCS Curve Number Designations

Wesley Chapel, North Carolina
Project Number: 6198
May 25, 2018
24 Hour Storm Event
Pre Development
Soil Type: TbB2-Tarrus Gravelly Silty Clay Loam - HSG "B"
Total Drainage Area = 12.58 ac.
Roofs, driveways, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 61
Woods 1.61 ac.
CN = 55
Pasture, grassland or range 10.97 ac.
CN = 61
Composite CN 60
Soil Type: BdB2-Badin Channery Silty Clay Loam - HSG "C"
Total Drainage Area = 28.49 ac.
Roofs, driveways, ponds, etc 0.43 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 74
Woods 5.16 ac.
CN = 70
Pasture, grassland or range 22.90 ac.
CN = 74
Composite CN 74
Soil Type: ChA-Chewacla Silt Loam - HSG "B/D"
Total Drainage Area = 5.65 ac.
Roofs, driveways, ponds, etc 0.06 ac.
CN = 98
Dirt 1.04 ac.
CN = 89
Woods 1.90 ac.
CN = 77
Pasture, grassland or range 2.65 ac.
CN = 80
Composite CN 81
Cavesson Subdivision
COMPOSITE SCS RUNOFF CURVE NUMBERS
Wesley Chapel, North Carolina
Project Number: 6198
May 25, 2018
24 Hour Storm Event
Post Development
Soil Type: TbB2-Tarrus Gravelly Silty Clay Loam - HSG "B"
Total Drainage Area = 10.72 ac.
Roofs, driveways, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 61
Woods 0.00 ac.
CN = 55
AVERAGE LOT SIZE = 1 ACRE 10.72 ac.
CN = 68
Composite CN 68
Soil Type: BdB2-Badin Channery Silty Clay Loam - HSG "C"
Total Drainage Area = 13.20 ac.
Roofs, driveways, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 74
Woods 0.00 ac.
CN = 70
AVERAGE LOT SIZE = 1 ACRE 13.20 ac.
CN = 79
Composite CN 79
Soil Type: Cmb-Cid Channery Silt Loam - HSG "D"
Cavesson Subdivision
COMPOSITE SCS RUNOFF CURVE NUMBERS
Wesley Chapel, North Carolina
Project Number: 6198
May 25, 2018
24 Hour Storm Event
Post Development Bypass 1
Soil Type: TbB2-Tarrus Gravelly Silty Clay Loam - HSG "B"
Total Drainage Area = 1.86 ac.
Roofs, driveways, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 61
Woods 0.00 ac.
CN = 55
Pasture, grassland or range 1.86 ac.
CN = 61
Composite CN 61
Soil Type: BdB2-Badin Channery Silty Clay Loam - HSG "C"
Total Drainage Area = 6.65 ac.
Roofs, driveways, ponds, etc 0.43 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 74
Woods 1.97 ac.
CN = 70
Pasture, grassland or range 4.25 ac.
CN = 74
Composite CN 74
Cavesson Subdivision
COMPOSITE SCS RUNOFF CURVE NUMBERS
Wesley Chapel, North Carolina
Project Number: 6198
May 25, 2018
24 Hour Storm Event
Post Development Bypass 2
Soil Type: BdB2-Badin Channery Silty Clay Loam - HSG "C"
Total Drainage Area = 6.76 ac.
Roofs, driveways, ponds, etc 0.43 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 74
Woods 0.53 ac.
CN = 70
Pasture, grassland or range 5.80 ac.
CN = 74
Composite CN 75
Soil Type: ChA-Chewacla Silt Loam - HSG "B/D"
Total Drainage Area = 5.65 ac.
Roofs, driveways, ponds, etc 0.06 ac.
CN = 98
Dirt 1.04 ac.
CN = 89
Woods 1.90 ac.
CN = 77
Pasture, grassland or range 2.65 ac.
CN = 80
Composite CN 81
Cavesson Subdivision
COMPOSITE SCS RUNOFF CURVE NUMBERS
Wesley Chapel, North Carolina
Project Number: 6198
May 25, 2018
24 Hour Storm Event
Post Development Bypass 3
Soil Type: TbB2-Tarrus Gravelly Silty Clay Loam - HSG "B"
Total Drainage Area = 0.32 ac.
Roofs, driveways, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 61
Woods 0.00 ac.
CN = 55
Pasture, grassland or range 0.32 ac.
CN = 61
Composite CN 61
Soil Type: BdB2-Badin Channery Silty Clay Loam - HSG "C"
Total Drainage Area = 1.66 ac.
Roofs, driveways, ponds, etc 0.00 ac.
CN = 98
Open Space (Good Condition) 0.00 ac.
CN = 74
Woods 0.00 ac.
CN = 70
Pasture, grassland or range 1.66 ac.
CN = 74
Composite CN 74
Cavesson Subdivision
COMPOSITE SCS RUNOFF CURVE NUMBERS
Cavesson Subdivision - Wesley Chapel, NC EEI Project #6198
Stormwater Management Report May 28, 2018

Appendix D
Riser Uplift Calculations
Rip-rap Calculations
Erosion Control Plan & Calculations

Project Name: Cavesson Subdivision
Project No.: 6198
551 ft. Top of Basin
1 ft. Spillway Height
550 ft. Spillway Elev.
Riser Width:48 in
Riser Thickness:6 in 549 ft. Riser Weir
Barrel Size:24 in 48 in. RISER
Top of Basin:551 ft.
Bottom of Basin 541 ft.8 ft. 9 ft.
Riser Weir:549 ft.
Spillway Height from top of Basin:1 ft.
541 ft. Bottom of Basin
Riser Buoyancy Calculations - Dry Detention Pond

Unit wt. of H20 62.4 ft3
Volume of Riser 160 ft3
Wt. of H20 displaced in riser 9,984 lbs
Unit Wt. of concrete (pcf)150 lbs/ft3 Ballast Pad 24 in. RCP
Volume of concrete in riser 37.5 ft3
Wt. of concrete riser 5,625 lbs
Total Buoyancy Force to displace 15,609 lbs

48 in. RISER
Concrete Base Required to Stabilize Riser:
Concrete Pad Thinckness 18 in.
Concrete Pad Width/length 10 ft Ballast Pad
Volume of concrete pad 150.00 ft3
Wt. of H2O displaced =9,360 lbs
Wt. of concrete pad 22,500 lbs 18 in.

Factor of Safety: 1.4415 OK 10 ft.
10 ft. X 10 ft. X 18 in.
10 ft.
Ballast Pad Dimensions:
Wt. of H20 displaced in riser + Wt. of concrete riser
Factor of safety should be greater than 1.10
Channel Report
Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Tuesday, Jun 5 2018
6198 BMP POND DITCH (Q25 = 2.56 cfs)
Trapezoidal
Bottom Width (ft) = 6.00
Side Slopes (z:1) = 2.00, 2.00
Total Depth (ft) = 4.00
Invert Elev (ft) = 540.61
Slope (%) = 0.77
N-Value = 0.150
Calculations
Compute by: Known Q
Known Q (cfs) = 2.56
Highlighted
Depth (ft) = 0.63
Q (cfs) = 2.560
Area (sqft) = 4.57
Velocity (ft/s) = 0.56
Wetted Perim (ft) = 8.82
Crit Depth, Yc (ft) = 0.18
Top Width (ft) = 8.52
EGL (ft) = 0.63
0 5 10 15 20 25 30 35
Elev (ft)Depth (ft)Section
539.00 -1.61
540.00 -0.61
541.00 0.39
542.00 1.39
543.00 2.39
544.00 3.39
545.00 4.39
Reach (ft)
Project Name: Cavesson Date:Location: Wesley Chapel, NC By:Description: DRY POND RISER DISCHARGE - FES-200Runoff Discharge InformationQ25 = 155.2 cfsPipe Dia. = 24 in.Apron SizingLength = 13 ft.Width = 15 ft.3Do @ Pipe = 6 ft. Riprap Stone Sizing (d50)d50 Size (Avg) = 0.4 ft.d50 Size (Max.)* 0.6 ft.Min. Depth** = 1.25 ft.* equal to 1.5*d50 average stone size** min. depth no less than 15"NOTES:1.0 Riprap aprons to be sized for 10-year discharge rate from each storm pipe discharge location, including sediment basins.2.0 Min. depth shall be equal to 1.5*d50 maximum riprap stone size, but in no case shall be less than 15" in depth.3.0 Abbreviations:La= Length of riprap apron in feet (determined from chart)(10' min.)Do= Size of outlet pipe (discharge pipe from storm drainage system in feet or inches)W= Width of riprap apron in feet (at end furthest from outlet pipe discharge)3Do= Width of rip rap apron in feet (at outlet pipe)d50= Size of stone in feet5/25/2018K.E.W.
Project Name: Cavesson Date:Location: Wesley Chapel, NC By:Description: FES-100Runoff Discharge InformationQ10 = 83.95 cfsPipe Dia. = 48 in.Apron SizingLength = 26 ft.Width = 30 ft.3Do @ Pipe = 12 ft. Riprap Stone Sizing (d50)d50 Size (Avg) = 0.9 ft.d50 Size (Max.)* 1.35 ft.Min. Depth** = 1.25 ft.* equal to 1.5*d50 average stone size** min. depth no less than 15"NOTES:1.0 Riprap aprons to be sized for 10-year discharge rate from each storm pipe discharge location, including sediment basins.2.0 Min. depth shall be equal to 1.5*d50 maximum riprap stone size, but in no case shall be less than 15" in depth.3.0 Abbreviations:La= Length of riprap apron in feet (determined from chart)(10' min.)Do= Size of outlet pipe (discharge pipe from storm drainage system in feet or inches)W= Width of riprap apron in feet (at end furthest from outlet pipe discharge)3Do= Width of rip rap apron in feet (at outlet pipe)d50= Size of stone in feet5/25/2018K.E.W.
Project Client
Project #Date
Designation Designer
Total Drainage Area 12.32 Acres 536,659 Square Feet
Total Disturbed Area 3.19 Acres 138,956 Square Feet
C 0.50 Contour Area Volume Net Volume
TC 5 Minutes 575 5,190 00
I10 7.03 Inches per Hour 576 11,309 8,250 8,250
Q10 43.30 CFS 577 18,065 14,687 22,937
578 25,456 21,761 44,697
Required Volume 11,484 Cubic Feet 579 31,285 9,156 53,853
Required Surface Area 18,838 Square Feet
Provided Volume 44,697 Cubic Feet OK
Provided Surface Area 25,456 Square Feet OK
Length 245 Feet
Width 120 Feet Q10 43.30 CFS
L/W Ratio 2.04 OK H 1 Feet
C 3
Spillway Elevation 578
Surface Area at Spillway 25,456 L 14.43 Feet
2013A Van Buren Ave.
Spillway Design
SKIMMER BASIN
CAVESSON BOWMAN
6198 5/28/2018
SKIMMER BASIN 1 KEW Indian Trail, NC 28079
NC Erosion and Sediment Control Planning and Design Manual
Minimum Spillway Design
Spillway Length 20 Feet Days to Drain 3 Days
Head over Spillway 1 Feet Skimmer Size 4 Inches
Weir Coefficient 3 Orifice Radius 1.7 Inches
Max Flow 60 CFS OK Orifice Diamter 3.4 Inches
Spillway Design
EAGLE, ENGINEERING, INC.
 2013 VAN BUREN AVENUE, STE A
INDIAN TRAIL, NORTH CAROLINA 28079
Project Client
Project #Date
Designation Designer
Total Drainage Area 12.32 Acres 536,659 Square Feet
Total Disturbed Area 3.19 Acres 138,956 Square Feet
C 0.50 Contour Area Volume Net Volume
TC 5 Minutes 575 5,190 00
I10 7.03 Inches per Hour 576 11,309 8,250 8,250
Q10 43.30 CFS 577 18,065 14,687 22,937
578 25,456 21,761 44,697
Required Volume 11,484 Cubic Feet 579 31,285 9,156 53,853
Required Surface Area 18,838 Square Feet
Provided Volume 44,697 Cubic Feet OK
Provided Surface Area 25,456 Square Feet OK
Length 245 Feet
Width 120 Feet Q10 43.30 CFS
L/W Ratio 2.04 OK H 1 Feet
C 3
Spillway Elevation 578
Surface Area at Spillway 25,456 L 14.43 Feet
2013A Van Buren Ave.
Spillway Design
SKIMMER BASIN
CAVESSON BOWMAN
6198 5/28/2018
SKIMMER BASIN 1 KEW Indian Trail, NC 28079
NC Erosion and Sediment Control Planning and Design Manual
Minimum Spillway Design
Spillway Length 20 Feet Days to Drain 3 Days
Head over Spillway 1 Feet Skimmer Size 4 Inches
Weir Coefficient 3 Orifice Radius 1.7 Inches
Max Flow 60 CFS OK Orifice Diamter 3.4 Inches
Spillway Design
EAGLE, ENGINEERING, INC.
 2013 VAN BUREN AVENUE, STE A
INDIAN TRAIL, NORTH CAROLINA 28079
Project Client
Project #Date
Designation Designer
Total Drainage Area 26.66 Acres 1,161,310 Square Feet
Total Disturbed Area 9.98 Acres 434,729 Square Feet
C 0.50 Contour Area Volume Net Volume
TC 5 Minutes 541 18,154 00
I10 7.03 Inches per Hour 542 20,250 19,202 19,202
Q10 93.71 CFS 543 22,445 21,347 40,549
544 24,738 23,591 64,141
Required Volume 35,928 Cubic Feet 545 27,130 25,934 90,074
Required Surface Area 40,764 Square Feet 546 29,620 28,375 118,449
547 32,198 30,909 149,358
Provided Volume 278,573 Cubic Feet OK 548 34,848 33,523 182,881
Provided Surface Area 41,762 Square Feet OK 549 37,566 36,207 219,088
550 40,348 38,957 258,045
550.5 41,762 20,528 278,573
Length 417 Feet
Width 176 Feet Q10 93.71 CFS
L/W Ratio 2.37 OK H 0.5 Feet
C 3
Spillway Elevation 550
Surface Area at Spillway 40,348 L 88.35 Feet
2013A Van Buren Ave.
Spillway Design
SKIMMER BASIN
CAVESSON BOWMAN
6198 5/28/2018
SKIMMER BASIN 3 KEW Indian Trail, NC 28079
NC Erosion and Sediment Control Planning and Design Manual
Minimum Spillway Design
Spillway Length 32 Feet Days to Drain 5 Days
Head over Spillway 1 Feet Skimmer Size 6 Inches
Weir Coefficient 3 Orifice Radius 3.0 Inches
Max Flow 96 CFS OK Orifice Diamter 6.0 Inches
Spillway Design
EAGLE, ENGINEERING, INC.
 2013 VAN BUREN AVENUE, STE A
INDIAN TRAIL, NORTH CAROLINA 28079