SW3140601_2019-06-14, CY at Marvin, Stormwater Report ,Asbuilt_9/10/2019

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301 McCullough Dr. Suite 109
ormwater Management Report
Charlotte, NC 28262 Courtyards at Marvin
Phone: [phone]
Toll Free: 1-888-775-EMHT Epcon Communities
emht.com
June 14, 2019
2013-1720

1.0 INTRODUCTION
The Project is a proposed single family subdivision with 61 lots and associated roadways. The
existing site condition is residential property with one (1) home and two (2) out buildings. A large
portion of the site is undeveloped open space with high brush grass. Small portions of the site are
wooded. The site generally slopes from east to west. An existing drainage ditch exists along the
western property line and conveys both the onsite and off -site stormwater runoff downstream to
the south.
Currently, a 10.15 acre area of land east of Providence Road has watershed that drains towards
Providence Road, is collected and conveyed by a roadside ditch, passes under Providence Road
via an existing 24 inch culvert and then is conveyed by a drainage channel along the project
south property line to the west un-named stream. This project will continue the watershed runoff
conveyance under Providence Road and will route the stormwater through the proposed
stormwater wet pond BMP. This drainage area was modeled in the post development condition as
future build out with '/a acre single family lots. The existing 24 inch culvert was analyzed in the
post development condition; analysis is included herein.
2.0 EXISTING HYDROLOGY
The existing conditions hydrology is exhibited on the Pre -Development Tributary Plan within
Appendix A of this report. The site drains to an un-named channel which drains to the southwest
from the western property line. The time of concentration for each tributary area is shown on the
Pre -Developed Plan in Appendix A. The rainfall depths used are shown in Table 2.0
Table 2.0: Rainfall Depths
Storm Event
Rainfall Depth
Rainfall Distribution
WQ
1.00
6-hr Type II
1-year
2.58
24-hr Type II
2-year
2.28
6-hr Type II
10-year
3.72
6-hr Type II
25-year
4.38
6-hr Type II
50-year
4.92
6-hr Type II
100-year
5.34
6-hr Type II
3.0 PROPOSED CONDITIONS
Stormwater management for this project will be provided by two permanent wet basins that are
connected by an equalizer pipe. The wet pond BMP is designed to Mecklenburg County
Stormwater Control criteria. The basin will have a forebay and permanent pool which will
provide the required water quality volume and will attenuate the peak rate of runoff from the
proposed basin. The on -site and off -site stormwater runoff is routed through the wet ponds such
that the 1-inch depth runoff is detained 48 hours providing the required 85% Total Suspended
Solid (TSS) removal. The Post -Developed Tributary Plan in included within the Construction
Documents. Stormwater release rates for the 1, 2, 10, 50 and 100 year storm occurrence are

controlled by an outlet structure device. The surface basins serve as both stormwater quality and
quantity control devices. Output from the HydroCAD model is included in Appendix A. The
NCDENR Supplemental Wet Pond BMP Forms Supplemental EMHT Calculation Worksheet are
attached in Appendix B.
4.0 STORMWATER MANAGEMENT DESIGN
The overall watershed contributing to the analysis point is 40.78 ac with 31.10 acres contributing
to the stormwater management basin. There is 9.68 acres that by-pass the proposed basin, but
contribute and included in the overall pre to post development analysis. 10.15 acres of
contributing watershed is from the east side of Providence Road and will be conveyed through a
new culvert under Providence Road to the project site. Under post development, future build -out
condition of the 10.15 acre watershed, the existing 24 inch culvert is under sized for the 50 year
storm event. A new 36 inch culvert will be installed under Providence Road and will convey both
the 50 year and 100 year events within NCDOT design standards (see culvert calculations in
appendix C). The entire contributing area to the stormwater basin will be modeled using SCS
methods utilizing the HydroCAD software to develop the pre and post development hydrographs,
peak runoff rates and routing calculations through the wet pond BMP structure. Water quality is
provided by the WQ volume reserved in the wet pond with quantity runoff control provided by
the pond volume above the WQv elevation.
The collective 40.78 acre onsite and offsite watersheds will be modeled to restrict the post
development runoff peak flow rates to those of the pre -development as described above.
The 100 year event HWL will not top the detention basin crest. Each post development peak flow
rate is less than the same year pre -development peak flow rate for the total watershed of the
improvement area.
Table 4.0: Combined Hydrograph Summary Table
Combined Summary Table
Event
Pre-Dev
Peak Flow
(cfs)
Post-Dev
Inflow (cfs)
As -Built
Post-Dev
Inflow (cfs)
1
3.94
1.55
0.95
2
3.89
2.14
0.93
10
29.22
26.05
23.28
25
49.17
36.72
34.46
50
66.53
44.60
42.78
100
81.01
49.68
48.39

Wet Pond Outlet Control
The outlet control is a two (2) stage structure. The primary control is provided by one (1) 2.50 inch
orifice with invert set at 589.15 feet. The volume provided for the water quality is from the wet
pond normal pool elevation (589.15) to the crest of the secondary outlet control. The secondary
outlet control is provided by three (3) 30.0 inch wide by 8.0 inch high slot weirs with crests set at
591.50 located on the face of the concrete control structure box. A 30 feet long emergency weir
is included along the top of the detention basin; the crest of the emergency weir is set at 593.50.
The top of the wet pond is 594.00.
Wet Pond Water Quality Summary Table
Event
Peak Inflow (cfs)
Peak Discharge
(cfs)
Peak HWL (ft)
Peak Storage
(cu-ft)
WQ (HydoCAD)
4.09
0.09
3.89.8.9 589.52
9-,9-6-2 9,990
2.0 feet
9-.2-3 0.38
39139 591.53
61,169- 75,288
Wet Pond
Routing Calculation Table
Event
Post-Dev
Inflow (cfs)
Post Dev
Routed Peak
(cfs)
Basin Peak
HWL (ft)
Basin Peak
Storage (cu-ft)
1
32.66
1.39
591.63
64,794
2
31.15
1.91
591.67
67,118
10
71.38
21.52
592.62
102,748
25
100.68
29.14
593.27
1291107
50
120.75
42.56
593.75
149,487
100
136.67
60.32
593.97
159,189
Wet Pond Routing As -Built Table
Event
Post-Dev
Inflow (cfs)
Post Dev
Routed Peak
(cfs)
Basin Peak
HWL (ft)
Basin Peak
Storage (cu-ft)
1
32.66
0.84
591.58
77,185
2
31.15
0.38
591.53
75,288
10
71.38
19.10
592.46
109,995
25
100.68
27.17
593.08
135,208
50
120.75
35.57
593.62
158,497
100
136.67
52.07
593.88
170,061

Providence Road Crossing Culvert Analysis
The existing 24 inch culvert that conveys the 10.15 acre east watershed under Providence Road
experiences 31.54 cfs for the 50 year event and 36.1 A cfs for the 100 year event. The existing
24 inch culvert is a CMP pipe, 37.4 ft at 1.98% slope. NCDOT requires that a culvert pass a 50
year storm event while developing less than 1.20 HW/D. The existing culvert experiences a
HW/D of 2.72. A new 36 inch, RCP culvert is proposed to replace the existing culvert. The new
culvert will be 63.39 feet long and have a 3.75% slope. The 36 inch culvert is inlet control and
the calculated HW/D is 0.88 for the 50 year event and 0.96 for the 100 year event. The 100
year event peak HWL will not top the road. See Appendix C for culvert calculations.
Providence Road Driveway Culvert Analysis
A private driveway existing near the proposed development entry driveway. The existing
driveway does not have a culvert and currently stormwater builds up at upstream side till it over
tops the driveway and/or soaks into the ground or evaporates.
The project proposes a new culvert to facilitate the stormwater conveyance to the new 36 inch
Providence Road crossing culvert to be further conveyed by our stormwater system. The centerline
of the proposed driveway culvert is 0.85 feet off the right-of-way line. For the 10 year storm, the
required driveway culvert size is 24 inch, conveying the 10.15 acre east watershed and
developing 1 1.74 cfs for the 10 year event. A new 24 inch, RCP culvert is proposed for the
driveway culvert. The new culvert will be 22.88 feet long and have a 1.05% slope. The 24 inch
culvert is inlet control and the calculated HW/D is 0.94 for the 10 year event. See Appendix C
for culvert calculations.

APPENDIX A:
Stormwater Management Calculations

� 3S
Marvin Onsite Pre Dev
4S
OS-E to Pond (10.15) 5L
6S (new Link)
OS -NW (6.11)
7S
OS-S (4.43)
Subcat Reach on Link Routing Diagram for 20131720 Wet Pond-final-6hr-v2
Prepared by (enter your company name here), Printed 6/11 /2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr WO Rainfall=1.00"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 32
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WO Rainfall=1.00"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
❑ Runoff
Oharlptte 6ihr', 2-yr
WQ Rainfal!=1.00"
Runoff 'Ar6a-20'6090 ac
Runoff V'olgl mP14.000 Of
Runoff Depth=0.00"
Flow L?noth,-1 �335'
Tc;-1$J7 min
CN=61
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr WO Rainfall=1.00"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 33
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WO Rainfall=1.00"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
❑ Runoff
Oharlptte, 6ihr', 2-yr
WQ Rainfal!=1.00"
Runoff 'Area=10'6150 ac
Runoff V'olump=0.000 if
Runoff IDepth-0.00"
Flow L?noth,-2�005'
Tc;-2$.3', min
CN-01
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr WO Rainfall=1.00"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 34
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WO Rainfall=1.00"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
❑ Runoff
Oharlotte 6ihr', 2-yr
WO Rainfall=1.00"
Runoff Awes=6161 TO ac
Runoff V'olum4p=O.OQO of
Runoff Depth=0.00"
Flow 1-6noth,-1 �981'
Tc'-2',1.0', min
CIS=61
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr WO Rainfall=1.00"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 35
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WO Rainfall=1.00"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
❑ Runoff
Ohorlptte 6ihr', 2-yr
WQ Rainfa11-1.00"
Runoff Awes=46430 ac
Runoff V010m0=0.000 Of
Runoff Depth=0.00"
Flow'Length=852'
Tc;-15.2', min
CN=61
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 36
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 0.00" for WO event
Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of
Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
■ Inflow
■ Primary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Type // 24-hr 1 yr Rainfall=2.58"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 2.32 cfs @ 12.16 hrs, Volume= 0.368 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
2.32 cfs
,Type 11 24-h;lr
-- -- - - --- - ---------+----
2 - ---I yr-Rainfafl-2-58"-
Runoff Arl§a=20'6090 ac
Runoff V'�olLJIMP14.308 pf
Runoff De��pth=0.22.,
3 Flow L6ndth'-lM5TI
a
- ---- -- - --
Tc;=10.7', mi',n
CAI=f 1
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
❑ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Type // 24-hr 1 yr Rainfall=2.58"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 0.84 cfs @ 12.36 hrs, Volume= 0.186 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
0 9 I I I I I I I I I I
I I I I I I I I I I I I I I I I I I
0.84 cfs T T I I I
�� 0.85 Type.11-�I4 hr-
08
--7---r--I---I--T---I---I--I---I---T---I-----7------r--I---I --7--
0.75 --7-- -r--7------T------r--7---r--T------fi-yr-Rainf-aH=2.58„-
0.7 --r---r-- r--- r-- r------r-- r---
I ---+ --- r ----r -
- Rundf� r4rda- (1150 Ac
0.65 - -r ---r--r------r------r- r- r t------r--r------r--r---r--r--
0.6 --+-- -+--+------+------r--+---I--
furlo# VpA#-
0.55 --+-- -+--+---I---+---I---+--+---I---+--+---+--+---+--+--+---I---+--
0.5 unQf#_IIQepth,0-22- -
c0.45 -- -- - -- ------+---I--- -- ------+---I- 1 1
LL
F116V1� tnth�,,O05'
0.4 -- -- -- ------+---I--- -- ------+---I- -----I---
0.35 _I -_ I _i liI_ -
I I I I I I I I I I I I Inc, 2 .3 xnin-
I
0.3 -- -- ------I--- + ---I--- -- ---I--- +------I------I--- ---I - -
0.25 C -�
--�-- --------------------------------
0.2
0.15
0.1
I--
n nr;
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Type // 24-hr 1 yr Rainfall=2.58"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 0.61 cfs @ 12.23 hrs, Volume= 0.112 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
0.65
--� 0.61 cfs-L--�---�---�---�---L--�---�---L---�---L--�---�---L--�---�---�--
� ell-2'4-Mr_
0.6 I I I I I I I I I I I I I I yp
0.55 _ I yr Rainfall=158„
0.5 �,y�
--rt--Ilo
-r---------7------r-----I---+- ff-Afew-M-10 ac-
0.45
- -- -r- -- +--- r-- --i 1urrof Vptpm4p=-O.1 f2-1Of
0.4
w--II-- ------------------------u---
0.35--I-Rl n©ff-IQepth-0.22"-
-- -- ---'-- -- -- -- ---- I
0.3 6=
RbW Inc t =1,198'1
0.25 ITc-21
L.II milln
-1- L--J---1---1---1---L-- ------1------L--1--------J------1--
0.15
0.1
-- -- - r-
-+------ r------r-- +---
---r-----r--r-----I--- --
0.05 I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Type // 24-hr 1 yr Rainfall=2.58"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 0.54 cfs @ 12.14 hrs, Volume= 0.081 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
---------------------------------------------------------'--- --
0.6
0.54 cfs i i i i i i i i i i i
0.55 1 �I ---;--;---1---;---1---;--;--- ;--- ;-- ; - - -ypa 1- 4- r-
0.5 --rt---r—--- 1--- Y--- 1 --- r-- 1--- t--- 1---I-yr-RainfaH=I,%"-
0.45 p� "ff
M A A3I
0.4
-L-- -L - --J 1--- IL-- Runoff Vq["MAP=-0$1-Pf-
w 0.35
Runoff-Depth=022"-
-- -- - - --- - --- ;-----1--- --- 'F16-'�L-e"th='S521-
LL o.zs I I I I I I I I I I I I 1
---;--;--- 1---;--- 1---;--;---1---;------;--;---1Tc-l$.-2mn-
o z Al
-- - - -- ------ ------ --------+------ -- ---------CN_61-
0.15
0.1
0.05
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 6
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 0.22" for 1 yr event
Inflow = 3.94 cfs @ 12.19 hrs, Volume= 0.748 of
Primary = 3.94 cfs @ 12.19 hrs, Volume= 0.748 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
■ Inflow
■ Primary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 2.12 cfs @ 3.49 hrs, Volume= 0.227 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090
61 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
11.0
50
0.0100
0.08
Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.7
906
0.0400
3.22
Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
1.0
379
0.0370
6.07 199.99
Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
16.7 1,335 Total
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
2.12 cfs
-----t--- --- r-
-t------t--- t-- ,-hprlottel-6l hrl' 2=j1r
2
2-yr Rainfa[1=2.28"
Runoff 'Ar6a=20'6090 ac
kunof�llf V'olgmp=0.2�7 pf
Runoff Depth=6.14.,
3------1---' ---' 1--- 1--- - Tlowt6nOth,=1 133 '-
a
LL
1
Tc;=1 0.7 min
CN=61
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
❑ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 0.91 cfs @ 3.70 hrs, Volume= 0.115 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
N
3
a
LL
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
Oharlptte, 6ihr', 2-yr
2-yr Rainfall=2.28"
Runoff 'Area=10'6150 ac
Runoff V'olump=0.115 pf
Runoff IDept6o.14"
Flow L?noth,-2�005'
Tc;-2$.3', min
CN=61
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
❑ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 0.60 cfs @ 3.57 hrs, Volume= 0.069 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
0.65
�:O..60crs+------+--+---+--+------+--+---+--+--+---+--+---+--+--+---+--+--
0.6 --0hw1d9tte-6ihr',2-yr-
2-
0.55 r-Rainfau�2. !- - I - - -!--;------7---I---!--;---I---! --- -- -y 2$"-
0.5 1 1 11 1 1 1
-- + ----- -- --- +--R-uhoff-M-ea--&1-1'G ac-
0.45 1 1 1
11 1 1 1
-- -- ---Aunoff dptgrr 4p=-O 009-pf-
0.4
--------------------- ----------------- -k--off-bept�i-0.14t,-
= 0.35
3 ----------------=------=-------
-----------------------------I
NoW LOncdth=1,981-'-
0.25 �Tc-21.0' mi'n
----- --------+------ --------+------ -- --------�------�--
0.2
0.15
--i---r--r---r--r---i---r--r---r--+---i---r--r---i---r--r---r--r--
--I--- T -- 1------+---I--- T -- 1------+---I--- r -- 7---I--- T -- 1---I--- T --
0.05
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 10
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 0.48 cfs @ 3.46 hrs, Volume= 0.050 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
0.5 0.411 cfs
---'---------- '---+----------------+-----�'�pt�-6;h�
0.45
------;--;------;---I---;--;---I---T-----2-yr-RairdzH=2,28"-
0.4
ftoff-Mea=4643'Q ac-
0.35------;--;---+-----�'�---;--;---�'�-- 0ur_',ioff V'010MO-00-Of_
0.3 -- I ---Run©ff-both=01.14
0.25 Fldw �Leogth-�852'
0.2 Tc-1$.2� miin
---I--- T -- T------+---I- -- T -- T- - - I - -- T---I --- T -- T------+--,---I--- --
0.15 ICN=61
0.1
0.05
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 2-yr Rainfall=2.28"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 11
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 0.14" for 2-yr event
Inflow = 3.89 cfs @ 3.57 hrs, Volume= 0.461 of
Primary = 3.89 cfs @ 3.57 hrs, Volume= 0.461 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
■ Inflow
■ Primary
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 16.51 cfs @ 3.37 hrs, Volume= 1.129 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
--7---I--T------T------7------7--7---I--T------T------7------7--�---
18 ------r--7---r--r---I---r---I---r--T---r------r--r---I---r---I---r--.---
17 1s.51 cfs
---+--+---+-- --+--- --- +--+--- l,h- ojte�6-F1 fO- - - 16 7------+---I---+---I---L--I-----7------+--
15------i ---- -- ---------- --I�--------1-1-0=�R'ainfal'l-172"-
. I I I I I I I I I I I I
14 L------L------L------L------L--L------L------L---I---L---I---L--L---
13- - - - - IRUnbff 'Ar6a=2MN -ac- -
12 I -----------II------II------II 11 -----�urtol"10llr�r OO-1�9-Ofi-
� I
10 " I T--- T - -- T--- T - -- 7--7--- T-Rig-nof# IIDepth=0.67"-
-�
T--- T--- T--- T--- 7--T--- T-RCoW-Cbn thl'�T'336r-
T $
7------+------+------r------r--+---+--+------+---ITc,-10.71-mi -
6------+---I------I------I------------+---I---------L---I--- -- ---
I I I I I I I I I I I I I I I
5---1---1---I---L---I---L---I---L--L---I---L------L------L------ _1--
4
-------------------------------------------
2
{ I I I I I I I I I I I I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 13
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 6.48 cfs @ 3.55 hrs, Volume= 0.571 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
-------- 1---I------I---L -- L------ 1---I--- 1 --------- 1---I--- 1---I--- L --
7 Runoff
6.48 cfs
--III--- ---III--- lI----III---III--- ---III--- ---III---III--Charlotte--hr- jo-yr-
6
10-yr Rllainfal1=332"
-----7------t------r--------------Rwn6ff-'Ar6a=T061510 21c-
5 I 1 1 1 I 1 1 1 I
-----1---II---------IL-------1---I uf7ofllf Vll101-0m-O4.571-Af-
4 Runoff IIIDeIpth=0.67W1
3 ----Flow1-6ndth=2,0051-
LL
Tc;-2$.31II min
2 CN=f 1
-I--- L- - - I - -- L-- -I- --L -- L- - -I- -- L- - -I- -- L -- J- - -I- -- L- - -I- -- L- - -I-
-- L --
1 II II II II II II II II II II II II II II II II II II
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 4.52 cfs @ 3.44 hrs, Volume= 0.343 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
5f]
4.sz cfs
C',harlotte',6-Mr I0-yr
4 10-yr Rainfall=3.72"
Runoff Awea=661 TO ac
-- -- --- -- -----+--1, Ruoff V'olump=�-343-af-
3
Runoff �De�pth=0.67"
3 -- Taow_L6n q th1=1 981LL
-
2 �Tc'-2',1.0� min
CIS=61
1 I I I I I I I I I I I I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
❑ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 3.78 cfs @ 3.34 hrs, Volume= 0.249 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
--rt---Ir--+--- li---+---li---Ir--rt---Ir--+---li---r--y---Ir--+---Ir--+------r-- ■Runoff
4 3.78 cfs
C�,harlotte,6-h;lr I0-yr
10-yr Rainfa[1=3.72"
3 Runoff Awes=46430 ac
Runoff V'olLImp=0.249 Of
i-
-----i---'- ----- ---'L--1--- ---1--- '--- L_R-u_n_off Depth-Q.67"-
2 Flaw Lehgth=852'
Tc;-1$.2', mi',n
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 10-yr 10-yr Rainfall=3.72"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 16
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 0.67" for 10-yr event
Inflow = 29.22 cfs @ 3.40 hrs, Volume= 2.293 of
Primary = 29.22 cfs @ 3.40 hrs, Volume= 2.293 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
'
■Inflow
32
��--,---I---r--T---I---r--r---I---r--r--�---r--T--�---I---r--r---I---r--
29.22 cfs
❑ PYImdY y
30
29.22 cfs------'I
-- ------'I
-- ---'---I
-
p R
�,II QWI ��V��40-780
a II(�
a
28
i
26
i
24
22
�� L---'---'---L---'---'---
L---'---L
--
L--
L------L--J------L-- J------L--
20
----------
-------------------------------------------
-------
---
N
18
1---I---_--T---I---_--T------r--T--1---I_--T--1------r--1------1--
3 16
LL 14
12
10
g
------'---
L------'---
L-- -'-
LI
- -L --
L
-- L- - -'--- L -- L---'--- L -- L- - -' -
-- L --
6
---
T ---
---
F
I
I I
F
4
--I---r
--T---I---r
--r---I---r--r--1---i
--T--1---I---r--1---I---r--
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 28.06 cfs @ 3.35 hrs, Volume= 1.696 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
30 I I I I
28.06 cfs------+------+------+------+----———— +--———— + -- —I— —+ -- — — — —
+---
26 I I - - - - - h,arl9tte- 6;-h r III-2-j/ar -
26 I I I I I I I
------+------r---I------I--- --------+-25-YrRllainfall1-4.30"-
24
----------------------------
---
22 RUnbff IIArba=201600'0 ac
---------- -------
20: ---Ii -- �II ------ Ii ------ Ii------Ii -- �II---quroIf-Vol4mq=J,606- f
w 1g
7--- I --- r--- -r--- -r--- -r----- T-RUnO-ffbepth--1-01''--
---------------------------------------------------------------
16
r------r1-----r1------rI-----r---I---r---I---r--r---r--r--F-lro- vr- LI-
n th6,314
12
------L------L--1------1---------- ITa=10.-7-mim-
I I I I I I I I I I I I I I I I I I
10 I
7 r r 7 7 T r r -6--
s----+------L------r-----+--------L------L------L--�--- + 7---
6 I I I
-- 7 I r 7 7
4
-- 7 T r 7 7-- 7---
----+---I------I------I--- --------+---I------I------I--- -- ---
2 I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD® 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 18
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 10.64 cfs @ 3.52 hrs, Volume= 0.857 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
1 1 1 o.64 ds /+ �+ � �
+---+--+---+--+--+---+--+---+--+---+--+---EhJarIgtte 6-,hr+2-yr--
10 1 i �
1---1---1---1---L---1---L---1---L--1-- +- 25-yrftirtfaf��f-4.38"--
s
- - RU"ff 'A1r$a=10'6150 -ac -
8
7
------7--- r------r--- r----- Runolf-Volumq=O:8$7-Af -
vy RUnaff DePthr_1O1„
+------+---+--+--+---+--+---+--+---+ + + -
3 6
o ------ + ---------i------------ ------ -Flow L-6rrothIC2�-005 -
-----
4 ----li -- +---i------i---------li -- ---li -- +---i-ITq-2$ 311 mrrr-
------7------r------r------'r--------rt------r------r--CN= 1--
2
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 19
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 7.58 cfs @ 3.41 hrs, Volume= 0.516 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
--+---+--+--+---+--+---+--+---+--+--+---+--+---+--+---+--+--+---+-- ■Runoff
8 7.Ss cfs
-- -------'Oh;I3rap##- 6hr'2-yr-
7 I 25 yr Rainfall=4.38"
6 IX Rurhoff Awea=661 TO ac
T--- ---! --- T-- -- T--1�UnDf'f V'�[PnW= •.51-6
5
-
----i---'- ----- ---'L--1--- ---1---'--- _R-unoff be,lath,=1��.01"-
4 I Flow 1-6noth'=1 �981'
3 I Tc=2 .0 mr,n
2
- --- --- --- --- ---GN_6F1-
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 20
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 6.48 cfs @ 3.32 hrs, Volume= 0.374 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
7 RUnoff
1.41 cfs
--- -- -- --- -- --- -----Oh;I3-raQt#��ihr-2-yr-
6
25 yr RaInfaII=4.38"
r---r--r---i---r--r---r--r---r--r---i-- - - --r- r i r--
5 1 11 u r10 1 Area= 1 0- 1
i------1---' --- 1--- 1--- Runoff V'ol-4mp=0 374-pf-
4 Runoff Depth=i.01
3 -- -- FIOw L-eftgth 85T-
g
Tc;-1$.2', min
---r--t---i---r------r--rt---r--+------r--y---r--t------r-
--i---r--
---�--- 1---�--- L---�---L -- 1---�--- 1---�--- L -- L---�--- 1---�--- r -- ---- L --
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 21
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 1.01" for 25 yr event
Inflow = 49.17 cfs @ 3.37 hrs, Volume= 3.442 of
Primary = 49.17 cfs @ 3.37 hrs, Volume= 3.442 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
■ Inflow
55
-------------------L---'---
4a.r7�fs
--L-------------------L--
---'---
--
❑Primary
50
7 �s
- - '-
- ltfaoan►'�I Area=40.7-80
-ac -
45
---li---t--t---li---t--t---li-
--t--t
--t---t--t--t---li---t--t---I--
-t--
40
L---------L---------L------L--L--
------L--J------L--J------L--
35
---I---i
-- T---I---i
--r------r--r--
---i --T--------r--------r--
y
w
1---I---I---1---I---I---1---I---L--1--J---I---1--J---I---L--J---I---L--
3
I I
I I I
I I
I I I
I I I I I I I I
I
° 25
-'---'---'----'---'---'---'----'---'---'---L--------------------------'---
LL
20
r------r--r------r--
r
------r--r
--r---r--r--r------r--r------r--
15
1---1---1---L---'---'---L---'---L--L--L------L--J------L--J------L--
10
------li
--t------li
--
------li --
---Ili---i --------i------------�i
- -
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 22
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 37.85 cfs @ 3.34 hrs, Volume= 2.212 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
42 --+---r--+------r------r--ti---r--+---r--+------r--+---r--ti---r--+---
40 37.85 ---r--+------r------r-----r--r---r --+---I---r------r-----r--r---
cfs {,� s� 38----------------------------------- - ---- h �� ttp �i�i�l2-I
36- --I-- - - - -I- - - ---I--- L------I------I--- +---------------------- -
+ I I I I I I I I I I I I C In I pI � I I AI (� I
34 ! ---I--- +---I------I---------I------I--- + - J0J y-1"111ainf ff-- ■.72'�--
32------+---I------I------I--- --------+---I------I------I--- -- ---
I RU"ff ri &a=20116-090 -aE
n
28 --------I------I------I-----------+--1-
__'I rp= i4i�r---
26 ----i -- + ---I--- i---I--- r---I---i -----�ul�o if-ar'Iblwm r f -
24---I---
3 ,I
------1++------II----L------II----LT------I---I ---I---
t6=11 -
—222 - ��
20•-r--
-
-------- fT+-BoW-tbth--1335--
I
16 I T---I---T------T------T------Ir--T---T--T------T --- ISO=1/.+7rliillfiii
12 I_------I------I------I---------I------I------I------I---li��-1--
8 I------+---I------I------I--- --------+---I------I------I--- -- ---
6 I --- -------
4-
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 23
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 14.35 cfs @ 3.50 hrs, Volume= 1.118 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
16 RUnoff
15 14.35cfs 1
---i--T---1---r---1---r---1---F T---i --T---1---r---1---r---1---r------
14 ' Ch'arlotte.-"r1,_2-yr ----I------I----------- - -
I--- -- ---I--- - -
13 ��
-- -- -- -- -- -- -- - 50-yr R1ainfaf1k4.92---
12
-- -- ---1 ---Rdnbff Ar6a=1O'6-t50 gic -
11
10 i ---III---Y---III---! ---III---! ---III---IlI_--- Ounoff_Vrolum4p=J,1 f8 of
N
---L------L------L---I--- L---I- L-Rianof# 11Depth=1:32"-
1I I I I I I I I I I
3 8
6 --III----11Ta-2$.311-ga'ulr> -
---�-----1------ T---1
5 ;-------------------r-- ---' --------+------------r--�CN=— 1--
4
3
---r--r---1---r---1---r---1---r--r---r--t---1---r---1---r---1---r--r---
2 -----L------L------L------L--L---I---L---I---L---I---L---I---L--L---
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 24
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 10.23 cfs @ 3.40 hrs, Volume= 0.673 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
11 I I I I I I I I I I I I I I I I I I I
10.23 cfs
T T T T—_ T T T-- T T-- 1---
10 Charlotte 6-hrll2-yr
9 50 yr Rllainfa[1=4.92"
8 Runoff Awea-6L11110 aC
7 I ---III --------II------II------Ir-- --- u o f of m�=0.673 �f
_I __L_ I _ L__ I___L__J___
6 Runoff IID�pth-11I.32"
5
4
--------T- Flow- Canoth,-I28 V
---I------I------I------I--- -----I------I--- ---ITC-21.-O,min -
I I I I I I I I I I I I I I I I I I
III---I------I-
3 I CN=61
---r--r---r--r---I---r---I---r--r---r--r---r--r---I---r---I---r--r---
2
-I---L---I---L---I---L---I---L--L---I---L---I---L---I---L---I---L--L---
1 I I I I I I I I I I I I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 25
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 8.74 cfs @ 3.31 hrs, Volume= 0.488 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
--T---r--T---1---r---1---r--4---r--T---1---r--r---r--T---1---r---1---r--
■ Runoff
9 8.7kcfs
I I I I I I I I I I I I I I I I I I 1
-- T------! ---------!------! -- h �'a -6ihf' -yK-
8 50 yr Rlai nfa[1=4.92"
7 — — — I — — — T— — — I — —— T—— ——T T— - T— - I-- - T— T—T T I— —— T --
7 Runoff Awea=46430 ac
7---1---T---1---r---1---1--7---1---T---ll uf7of,f Vl-- --- .4 8-�f-
6
N
I I I--- I II---T -- I
5 I--- I - - - I -- -ri ftrfoff,De1�-1:32"-
1
3 F]-6w7L-e"=852'-
a
4
-- --- -- -- -- -- -- --'1T-c=l$4m"In-
3
CN=61
2
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 26
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 1.32" for 50 yr event
Inflow = 66.53 cfs @ 3.36 hrs, Volume= 4.490 of
Primary = 66.53 cfs @ 3.36 hrs, Volume= 4.490 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
--+--------+------------- ---+--+--+------+--+------+--+------+--
■Inflow
❑ Primary
70
65.53
cfs + + +-�n �-�W+��� --40-780
65
60
55
50
_ 45
N-
- - - - - - - - - - - - - - - - - - -
c 35
30
25
20
---------------------------------------------------------------
10
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCADO 10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 27
Summary for Subcatchment 3S: Marvin Onsite Pre Dev
Runoff = 46.03 cfs @ 3.33 hrs, Volume= 2.641 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
0.780 98 Water Surface, HSG B
5.800 55 Woods, Good, HSG B
13.510 61 Pasture/grassland/range, Good, HSG B
20.090 61 Weighted Average
Tc Length
min) (feet)
11.0 50
Slope Velocity Capacity Description
(ft/ft) (ft/sec) (cfs)
0.0100
4.7 906 0.0400
1.0 379 0.0370
16.7 1,335 Total
0.08 Sheet Flow, Offsite Grasses & Weeds - Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.22 Shallow Concentrated Flow, Shallow Conc.
Unpaved Kv= 16.1 fps
6.07 199.99 Trap/Vee/Rect Channel Flow, Ex. Ditch
Bot.W=2.00' D=1.50' Z= 13.3 '/' Top.W=41.90'
n= 0.040 Natural ditch
Subcatchment 3S: Marvin Onsite Pre Dev
Hydrograph
--r---r--r---i---r---i---r---i---r--r---r--+---i---r---i---r---i---r--r---
50 -----�------�------�------�---� -----�------�------�---------------
48 46.03cfs---+--+---+--+------r--+---+--+---+--+---+--+--F+-*-#-r--+-{�--+ry--+---
46 ---------li------li------------ ---------i]�C1CCQtt�_if]C+2-�/J'
44+---r--+---+--r------r------r--+---r--+--- #,,rr-
42
40+---+--+---+--+--+---+--+---+--+---+--+���-vr-RMnfall= "r-
3$ I RU1K1bff ri6a=206-090 -aE
32------+------ ------ ------ -- ---FW fro#-l�olt�rttp-■61-f -
y 28-_-',-- ----- - + -Run ff-T=1 58- -
3 26 � i ---I� -- ------ ------ ------ -- ------ II — —I— — � — —II—Dept —I---�1 —I--
2z ' -- -- -- f_toW-tbnoft---1�`335
20 I+------+------+------+------+--+------+------+---i +- +------
i
-----------------------------------'�0=-galkl -
16 I+------+------r------------+--+------+------+----------/+—--�i--
14 I----------li-------li----------il -- - i�i--
12 I ------+------ ------ --------'------+------ ------ ------ -- ---
----- ------ ------------ -------
6 ---i -- +---i--- r---i------i---i -- ---i -- +---i--- r---i------i---i---i---
4-----+------ ------ ------ --------+------ ------ ------ -- ---
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 28
Summary for Subcatchment 4S: OS-E to Pond (10.15)
Runoff = 17.45 cfs @ 3.50 hrs, Volume= 1.334 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
10.150 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
7.4
714
0.0100
1.61
Shallow Concentrated Flow, Shallow Conc
Unpaved Kv= 16.1 fps
4.7
1,191
0.0100
4.19
25.17 Channel Flow, Channel
Area= 6.0 sf Perim= 7.7 r= 0.78' n= 0.030
28.3 2,005 Total
Subcatchment 4S: OS-E to Pond (10.15)
Hydrograph
— 7---I--- T— — —I--- r---I--- r---I--- r -- 7— — —I--- T— — —I--- r---I--- r---I---r---
19 I I RUnoff
r---r--T---r--r----- --r----- --r--r---r--T---r--r----- --r----- --r--r---
18 17.45 cfs 1 1 1 1 1 1 1 1 1 1 1 1 1 1
---r--T---1---r---1---r---1---r--�---r--T---I/-'�--r-- I---r---I---r/-�-�---
17---r--T---1r--r---1i---r---1i---Ir-----r--T---�h1k�Q##�+-��ilClr2-yr -
7---I--T---I---r---I---r---I---r— 7— T I— '—
,s - --1 - --1 - - - - - I -- 11108-�r Rainfal1=534''-
7— I— T— I— r— I— r— I— r--7---1---T---1--'r — r r--r---
14---r--T--- 11---T--- 11---r---11---r--T--- rRU"ff Aril a=l0'6M aie -
13 I I I
12---1---T---1---r---1---r---1---r--7---�u�o�f-�olum�=�,�-�
T---r--T---'1---T---'1---r---'1---r--T----
w 11
10 -- -- -- -- -- Runoff lDap#h-11r58'�=
7---I--T------r------r---I---r--7---I ——T———
—--r---I--
a 9
,�7---r--T--- 1---r--- 1---r---1---r--7--- r--T- Flow- U�n#lt,=2005'--
8
7 ---I -- T---I--- r---I--- r---I--- r -- 7 ---I -- T---1--- r---1—T— r r—y�� —
7---1r-----11--- 1r---11---r I -- 1r---11-4 C1= 31ir-M
6------ T --- 11- T---11- r---11---r--T--- r--T --- 11- T---11---T-- 1
5 -- -- - ---r -- ---r -- ---r -- ------ - ---r -- ---r---11C1 = 1--
4
1 T---r r---1- r--r- r--7---r T---r r---r F
3 ---r-- 1---11--- 1r---11---1r---11---r-- ------ 1---11--- 1r---11---1r---11---1r---11---
2
--r -- T---11--- r---11--- r---11--- r -- 7 ---r -- T---11--- r---11--- r--- 11---1r -- r ---
{ I I I I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 29
Summary for Subcatchment 6S: OS -NW (6.11)
Runoff = 12.44 cfs @ 3.39 hrs, Volume= 0.803 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
11.0
50
0.0100
0.08
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.7
1,390
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 '/' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.0 ? Top.W=55.00'
n= 0.030
21.0 1,981 Total
Subcatchment 6S: OS -NW (6.11)
Hydrograph
-- I' ---'--- I' ---'---'----'---'----'---'--- I' ---'---'----'---'----'---'----'---'----'--- ■Runoff
13 1 .44 cfs
12- --------------------harCOtte 6 hr,�2=yr -
11 - -- -- 100 yr Rainfall-5.34"
10 - _Ruhoff-AIreA-6-6--I-1'Q -qc -
u"If Vol4mp-0•803-�
1--- 1---1--- ---L--- ---L--- ---L--1--- O
8
I------I------I------I --- --------- ---+-Runaf#'�Depth--1-5891-
3 7 rF i}}��noit---r--r------r------r------r--r------+-Roth,Cfi�'981
.2a 1N LC6 y+
+---�--+---�---r---�---r---�---�--�---�--+---�---r---�To;-2'1.O,m%n
5
=-- -- -- ---- -- - ---'-- ---- ----------------------
4 CN=61
3
z
r--+------r------r------r--+---r--+---+--r------r------r--+---
1 i
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment 7S: OS-S (4.43)
Runoff = 10.63 cfs @ 3.31 hrs, Volume= 0.582 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
4.430 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
4.9
752
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
15.2 852 Total
Subcatchment 7S: OS-S (4.43)
Hydrograph
I I I I ■ Runoff
11 1as3cfs I I I I I I I I I I I I /'+ �I
+---+--+---+--+--+---+--+---+--+---I---+---Eh,ahlptte V hri-2-7'
10
1---1---+------ ------L------L--1------1100-yr Rai nfalll-S.-34"-
9 I I I I I I
- -Ra ho#f-kweal-46430 ac -
7 I I
+------+------+------+------+--+--- +-Ritma#f-��IDeptN =I-58"-
3 6 I I I I I I I I I I I I I I I I I I I
LL
-- - --- --I--- -- FI6w'tehgth=$52' -
s
I I I I I I I I I I I
-- - --- - --- ---I- -- To--1$.2' mIn--
---'I---7---'I---r---'I---r---'I---'r--�---'I---rt---'I---r---'I---r---'IC�1=�1--
3
2
1 I I I I I I I I I I I I I I I I I I
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

Courtyards at Marvin Project SWM - Pre-Dev
20131720 Wet Pond-final-6hr-v2 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by {enter your company name here} Printed 6/11/2014
HydroCAD®10.00 s/n 07459 © 2012 HydroCAD Software Solutions LLC Page 31
Summary for Link 5L: (new Link)
Inflow Area = 40.780 ac, Inflow Depth = 1.58" for 100 yr event
Inflow = 81.01 cfs @ 3.36 hrs, Volume= 5.361 of
Primary = 81.01 cfs @ 3.36 hrs, Volume= 5.361 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Link 5L: (new Link)
Hydrograph
--+---1-----+---1-----+-----+--+--+---1---+--+---1---+--+---1---+--
■Inflow
90
81.01 cfs
LI --1
■Primar y
85
81.01
cfs
---1---1---L---1---1---
---I I --- L-
—LInfow-
-Area=40.7-80
ac-
80------1L--i------1L--i-----1L--1--J---1---L--J---1---L--J---1---L--
75
70
65
60
55
�I---I---II----i---I---II---
N
50
3 45
- 1 -
1 - - 1
- 1 -
- 1 - 1 -
- 1 - 1 - - 1 - 1 - 1 - 1 - 1
- 1 -
c
40
I I
I I I
I I
I I
I
—
I I I I I I I I
—
1
35
T
T
T
T
T T-- T I T-- I
--T--T---1---r--T---1---r--
T
30
T---1---T--T---1---T--T---1---T--T--T---i
25
r---1---r--r---1---r--r---1---r--r--r---r--+--r---1---r--r---r--r--
1
20
r---I---I---r---1---r--r---1---r--r--r---r--t--r---1---r--r---1---r--
1
---1---r--+---1---r--+---1---r--+--+---r--+--+---1---r--+---1---r--
1 1
15
I I
I 1
I
1
In
1
1 I I
I I
1 I
I
I I I 1 1 1 1 1
1
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

2 SS
OS-E to Pond (10.15)
C2O S2OS
Marvin Onsite 21 P
Post -Ponds
Prop Retention Pond
22S �
OS-S (4.13)
2 SS
OS -SW (1.50)
25L
23S Post Site Discharge
OS -NW (6.11)
2 SS
Onsite Direct (3.57)
Subcat Reach on Link Routing Diagram for 20131720 Wet Pond-final-6hr-v2 -As Built-2019-06-17
Prepared by Symanetc, Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 28.48 cfs @ 12.03 hrs, Volume= 1.586 af, Depth= 1.24"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
06
5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 0.53 cfs @ 12.13 hrs, Volume= 0.076 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 0.50 cfs @ 12.36 hrs, Volume= 0.112 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 0.19 cfs @ 12.13 hrs, Volume= 0.046 af, Depth= 0.15"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
Subcatchment 24S: Onsite Direct (3.57)
Hydrograph
❑ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 6.53 cfs @ 12.18 hrs, Volume= 0.590 af, Depth= 0.70"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
10.150 75 1/4 acre lots, 38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 0.18 cfs @ 12.15 hrs, Volume= 0.028 af, Depth= 0.22"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Type II 24-hr 1 yr Rainfall=2.58"
Area (ac) CN Description
1.500
61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41
14.86 Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
Subcatchment 27S: OS -SW (1.50)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 8
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 0.88" for 1 yr event
Inflow =
32.66 cfs @
12.04 hrs,
Volume=
2.280 of
Outflow =
0.84 cfs @
18.76 hrs,
Volume=
1.760 af, Atten= 97%, Lag= 403.2 min
Primary =
0.25 cfs @
18.76 hrs,
Volume=
1.463 of
Secondary =
0.59 cfs @
18.76 hrs,
Volume=
0.297 of
Tertiary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 591.58' @ 18.76 hrs Surf.Area= 36,067 sf Storage= 77,185 cf
Plug -Flow detention time= 2,027.9 min calculated for 1.760 of (77% of inflow)
Center -of -Mass det. time= 1,932.9 min ( 2,788.2 - 855.3 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.25 cfs @ 18.76 hrs HW=591.58' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.25 cfs @ 7.35 fps)
Secondary OutFlow Max=0.59 cfs @ 18.76 hrs HW=591.58' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 0.59 cfs @ 0.93 fps)
Tertiary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' (Free Discharge)
L3= Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 9
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Type 11 24-hr 1 yr Rainfall=2.58"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 10
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 0.56" for 1 yr event
Inflow = 0.95 cfs @ 18.66 hrs, Volume= 1.918 of
Primary = 0.95 cfs @ 18.66 hrs, Volume= 1.918 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 25L: Post Site Discharge
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
I nflow
❑ Primary

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 28.34 cfs @ 3.24 hrs, Volume= 1.284 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 0.46 cfs @ 3.44 hrs, Volume= 0.047 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
4.130
61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41
14.86 Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
Subcatchment 22S: OS-S (4.13)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 13
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 0.54 cfs @ 3.71 hrs, Volume= 0.069 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 0.20 cfs @ 3.58 hrs, Volume= 0.025 af, Depth= 0.09"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
Subcatchment 24S: Onsite Direct (3.57)
Hydrograph
❑ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 6.22 cfs @ 3.44 hrs, Volume= 0.445 af, Depth= 0.53"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
10.150 75 1/4 acre lots, 38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
0
Subcatchment 26S: OS-E to Pond (10.15)
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 0.16 cfs @ 3.47 hrs, Volume= 0.017 af, Depth= 0.14"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr Rainfall=2.28"
Area (ac) CN Description
1.500
61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41
14.86 Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
Subcatchment 27S: OS -SW (1.50)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 17
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 0.69" for 2-yr event
Inflow =
31.15 cfs @
3.25 hrs,
Volume=
1.793 of
Outflow =
0.38 cfs @
6.30 hrs,
Volume=
1.460 af, Atten= 99%, Lag= 183.1 min
Primary =
0.25 cfs @
6.30 hrs,
Volume=
1.452 of
Secondary =
0.13 cfs @
6.30 hrs,
Volume=
0.008 of
Tertiary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 591.53' @ 6.30 hrs Surf.Area= 35,905 sf Storage= 75,288 cf
Plug -Flow detention time= 2,502.3 min calculated for 1.460 of (81 % of inflow)
Center -of -Mass det. time= 2,482.8 min ( 2,711.8 - 228.9 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.25 cfs @ 6.30 hrs HW=591.53' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.25 cfs @ 7.27 fps)
Secondary OutFlow Max=0.13 cfs @ 6.30 hrs HW=591.53' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 0.13 cfs @ 0.57 fps)
Tertiary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' (Free Discharge)
L3= Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 18
N
U
Pond 21 P: Prop Retention Pond
Hydrograph
Time (hours)
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 2-yr Rainfall=2.28"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 19
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 0.46" for 2-yr event
Inflow = 0.93 cfs @ 3.68 hrs, Volume= 1.554 of
Primary = 0.93 cfs @ 3.68 hrs, Volume= 1.554 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 25L: Post Site Discharge
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
I nflow
❑ Primary

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 20
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 57.02 cfs @ 3.23 hrs, Volume= 2.820 af, Depth= 2.21"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
Subcatchment 20S: Marvin Onsite Post -Ponds
Hydrograph
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 21
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 3.62 cfs @ 3.33 hrs, Volume= 0.232 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 22
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 3.87 cfs @ 3.55 hrs, Volume= 0.343 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 23
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 2.45 cfs @ 3.32 hrs, Volume= 0.161 af, Depth= 0.54"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 24
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 18.06 cfs @ 3.41 hrs, Volume= 1.235 af, Depth= 1.46"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
10.150
75 1/4 acre lots,
38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
Subcatchment 26S: OS-E to Pond (10.15)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 25
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 1.25 cfs @ 3.36 hrs, Volume= 0.084 af, Depth= 0.67"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 10-yr Rainfall=3.72"
Area (ac) CN Description
1.500 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 26
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 1.69" for 10-yr event
Inflow =
71.38 cfs @
3.25 hrs,
Volume=
4.372 of
Outflow =
19.10 cfs @
3.79 hrs,
Volume=
4.022 af, Atten= 73%, Lag= 32.5 min
Primary =
0.29 cfs @
3.79 hrs,
Volume=
1.489 of
Secondary =
18.81 cfs @
3.79 hrs,
Volume=
2.533 of
Tertiary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 592.46' @ 3.79 hrs Surf.Area= 39,100 sf Storage= 109,995 cf
Plug -Flow detention time= 962.1 min calculated for 4.022 of (92% of inflow)
Center -of -Mass det. time= 952.0 min ( 1,175.3 - 223.3 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.29 cfs @ 3.79 hrs HW=592.46' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.29 cfs @ 8.62 fps)
Secondary OutFlow Max=18.80 cfs @ 3.79 hrs HW=592.46' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 18.80 cfs @ 3.76 fps)
Tertiary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' (Free Discharge)
L3= Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 27
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-17 Charlotte 6-hr 10-yr Rainfall=3.72"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 28
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 1.33" for 10-yr event
Inflow = 23.28 cfs @ 3.70 hrs, Volume= 4.527 of
Primary = 23.28 cfs @ 3.70 hrs, Volume= 4.527 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
I nflow
❑ Primary
N
U
3
0
LL

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 29
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 78.56 cfs @ 3.23 hrs, Volume= 3.575 af, Depth= 2.80"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
Subcatchment 20S: Marvin Onsite Post -Ponds
Hydrograph
85
80
.................. ..................... .................... :................... :.................. :....................
Cf
.....:.....
......... .......... ......... ......... .......... ......... .......... ........ ......... ......... .......... ......... ......... ........
.....:..... .....:..... .....:.....
ar o - r yr
78.s6
75
70
.................. :........... ,
—
_ 26 yr F�ain_fa�l 4 :38„ .....
65
60
..._:...................:..............................................................................:...................:....................:......................................:..........................................................:..........................................................:....................:...................
. . . . .
Ru...n.bff..A.rb.a=..1...5320......ac .......
. . . . . . . . . . . . . .
55
. . . . .
. . . . .
. . . . . . . . . . . . . .
. . . . . . . . . . . . . .
u: o f alum: 3:5 5 0.
50
Runk#f D��th-2�. R
45
40
........................................ . .................. _.................._.................................................................................
_...........................................................................................................................................:........................................ _................... ...................
C
F h 1347 Flow: Ong
35
30
10
25
....................:...................,...................;...................................._..................................
—
— 5
20
15
10
5
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 30
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 6.24 cfs @ 3.31 hrs, Volume= 0.349 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 31
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 6.35 cfs @ 3.53 hrs, Volume= 0.516 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 32
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 4.50 cfs @ 3.29 hrs, Volume= 0.251 af, Depth= 0.84"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 33
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 25.74 cfs @ 3.40 hrs, Volume= 1.655 af, Depth= 1.96"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
10.150 75 1/4 acre lots, 38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 34
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 2.13 cfs @ 3.34 hrs, Volume= 0.127 af, Depth= 1.01"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Area (ac) CN Description
1.500 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 35
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 2.20" for 25 yr event
Inflow =
100.68 cfs @
3.25 hrs,
Volume=
5.705 of
Outflow =
27.17 cfs @
3.73 hrs,
Volume=
5.354 af, Atten= 73%, Lag= 28.7 min
Primary =
0.32 cfs @
3.73 hrs,
Volume=
1.496 of
Secondary =
26.85 cfs @
3.73 hrs,
Volume=
3.859 of
Tertiary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 593.08' @ 3.73 hrs Surf.Area= 41,648 sf Storage= 135,208 cf
Plug -Flow detention time= 734.4 min calculated for 5.354 of (94% of inflow)
Center -of -Mass det. time= 726.3 min ( 948.3 - 222.1 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.32 cfs @ 3.73 hrs HW=593.08' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.32 cfs @ 9.42 fps)
Secondary OutFlow Max=26.85 cfs @ 3.73 hrs HW=593.08' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 26.85 cfs @ 5.37 fps)
Tertiary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' (Free Discharge)
L3= Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 36
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 25 yr Rainfall=4.38"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 37
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 1.80" for 25 yr event
Inflow = 34.46 cfs @ 3.60 hrs, Volume= 6.121 of
Primary = 34.46 cfs @ 3.60 hrs, Volume= 6.121 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 25L: Post Site Discharge
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
Inflow
❑ Primary

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 38
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 91.97 cfs @ 3.22 hrs, Volume= 4.206 af, Depth= 3.29"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
Subcatchment 20S: Marvin Onsite Post -Ponds
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 39
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 8.41 cfs @ 3.30 hrs, Volume= 0.455 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
N
0
LL
Subcatchment 22S: OS-S (4.13)
Hydrograph
9
8.41
cfs
..._i.................... i...................«..................«.................... .........
......... ........ .......... ......... ......... ......... .......
h�lrlt�tt�.....6.wh..�,,...�.....�,f,.........
8
..._i....................i................... «.................. .......... .........
......... ........ .......... ......... ......... ......... 4.92 .......
7
Run off Area=4:130 ac
6
Runoff Volume=Q.465 oaf
5
....................... ................... .................. .................._...................
................... .................. .......
Runoff : Depth=1.3
4
.......................................................................... ........
........ ....... ... .......
_, dth�11348,
Flow: Lin.
3
CAI=C1
2
1
0
3 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 40
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 8.55 cfs @ 3.51 hrs, Volume= 0.673 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 41
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 6.29 cfs @ 3.28 hrs, Volume= 0.335 af, Depth= 1.13"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 42
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 31.53 cfs @ 3.40 hrs, Volume= 2.017 af, Depth= 2.38"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
10.150 75 1/4 acre lots, 38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 43
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 2.88 cfs @ 3.33 hrs, Volume= 0.165 af, Depth= 1.32"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Area (ac) CN Description
1.500 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 44
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 2.64" for 50 yr event
Inflow =
120.75 cfs @
3.25 hrs,
Volume=
6.842 of
Outflow =
35.57 cfs @
3.69 hrs,
Volume=
6.491 af, Atten= 71 %, Lag= 26.5 min
Primary =
0.34 cfs @
3.69 hrs,
Volume=
1.501 of
Secondary =
32.17 cfs @
3.69 hrs,
Volume=
4.936 of
Tertiary =
3.06 cfs @
3.69 hrs,
Volume=
0.054 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 593.62' @ 3.69 hrs Surf.Area= 44,725 sf Storage= 158,497 cf
Plug -Flow detention time= 615.0 min calculated for 6.491 of (95% of inflow)
Center -of -Mass det. time= 608.0 min ( 828.9 - 221.0 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.34 cfs @ 3.69 hrs HW=593.62' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.34 cfs @ 10.06 fps)
Secondary OutFlow Max=32.16 cfs @ 3.69 hrs HW=593.62' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 32.16 cfs @ 6.43 fps)
Tertiary OutFlow Max=3.04 cfs @ 3.69 hrs HW=593.62' (Free Discharge)
L3= Broad -Crested Rectangular Weir (Weir Controls 3.04 cfs @ 0.82 fps)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 45
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06- Charlotte 6-hr 2-yr 50 yr Rainfall=4.92"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 46
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 2.19" for 50 yr event
Inflow = 42.78 cfs @ 3.56 hrs, Volume= 7.444 of
Primary = 42.78 cfs @ 3.56 hrs, Volume= 7.444 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 25L: Post Site Discharge
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
I 1 nflow
❑ Primary

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 47
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 102.44 cfs @ 3.22 hrs, Volume= 4.703 af, Depth= 3.68"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
Subcatchment 20S: Marvin Onsite Post -Ponds
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 48
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 10.22 cfs @ 3.30 hrs, Volume= 0.543 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
■ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 49
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 10.40 cfs @ 3.50 hrs, Volume= 0.803 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.0 T Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
N
0
LL
Subcatchment 23S: OS -NW (6.11)
Hydrograph
1 10.40 cfs
.._i.................._i...................«...................«............. ..........
0
......... .......... ......... ......... ........................ ..........
ar oft - r yr
9
........................................................................................................................................................................._
.................._...................1..0p y.......r Rainfall=6.34.._i.r.........
.
.................. ................... ................... :.................. .........
........ ......... ........................... ......... ......
uno �ea� � �c
7
.....:.....
...........
—
uno: o um' �
6
....._......
— uno �p
5
Flow Length"I 9811
4
TG 287 min
3
.................................................... .....:..... ....... .........
........ ......... ....... ..... .....:.....
2
1
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)
❑ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 50
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 7.81 cfs @ 3.28 hrs, Volume= 0.405 af, Depth= 1.36"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 51
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 36.14 cfs @ 3.40 hrs, Volume= 2.307 af, Depth= 2.73"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
10.150
75 1/4 acre lots,
38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
Subcatchment 26S: OS-E to Pond (10.15)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 52
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 3.50 cfs @ 3.32 hrs, Volume= 0.197 af, Depth= 1.58"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Area (ac) CN Description
1.500 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 53
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 2.99" for 100 yr event
Inflow =
136.67 cfs @
3.25 hrs,
Volume=
7.750 of
Outflow =
52.07 cfs @
3.60 hrs,
Volume=
7.398 af, Atten= 62%, Lag= 21.1 min
Primary =
0.35 cfs @
3.60 hrs,
Volume=
1.504 of
Secondary =
34.39 cfs @
3.60 hrs,
Volume=
5.427 of
Tertiary =
17.33 cfs @
3.60 hrs,
Volume=
0.467 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 593.88' @ 3.60 hrs Surf.Area= 46,177 sf Storage= 170,061 cf
Plug -Flow detention time= 542.8 min calculated for 7.396 of (95% of inflow)
Center -of -Mass det. time= 537.5 min ( 757.7 - 220.2 )
Volume Invert
#1 589.15'
UVOIll
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.35 cfs @ 3.60 hrs HW=593.88' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.35 cfs @ 10.35 fps)
Secondary OutFlow Max=34.39 cfs @ 3.60 hrs HW=593.88' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate (Orifice Controls 34.39 cfs @ 6.88 fps)
Tertiary OutFlow Max=17.32 cfs @ 3.60 hrs HW=593.88' (Free Discharge)
L3= Broad -Crested Rectangular Weir (Weir Controls 17.32 cfs @ 1.53 fps)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 54
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
❑ Primary
" Secondary
p Tertiary
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06 Charlotte 6-hr 2-yr 100 yr Rainfall=5.34"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 55
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 2.40" for 100 yr event
Inflow = 48.39 cfs @ 3.51 hrs, Volume= 8.139 of
Primary = 48.39 cfs @ 3.51 hrs, Volume= 8.139 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
I 1 nflow
❑ Primary
N
U
3
0
LL

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 56
Summary for Subcatchment 20S: Marvin Onsite Post -Ponds
Runoff = 4.09 cfs @ 3.27 hrs, Volume= 0.222 af, Depth= 0.17"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
0.535 98 Retention Ponds
14.785 85 Prop Dev 65% Impery
15.320 85 Weighted Average
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
7.6
50
0.0250
0.11
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
3.2
1,425
0.0200
7.44 9.14
Pipe Channel, Storm Sewer
15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.013
10.8 1,475 Total
N
U
3
0
LL
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)
■ Runoff

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 57
Summary for Subcatchment 22S: OS-S (4.13)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
4.130 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.3
100
0.0467
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.0
298
0.0250
2.55
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
1.9
950
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
14.2 1,348 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 58
Summary for Subcatchment 23S: OS -NW (6.11)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
0.930 61 >75% Grass cover, Good, HSG B
5.180 61 Pasture/grassland/range, Good, HSG B
6.110 61 Weighted Average
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
19.1
100
0.0100
0.09
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
8.3
1,340
0.0276
2.67
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
0.8
241
0.0141
5.32
39.93
Trap/Vee/Rect Channel Flow, Trap Channel
Bot.W=2.00' D=1.50' Z= 2.07' Top.W=8.00'
n= 0.030
0.5
300
0.0400
10.48
628.76
Trap/Vee/Rect Channel Flow, Trap Channel 2
Bot.W=25.00' D=1.50' Z= 10.07' Top.W=55.00'
n= 0.030
28.7 1,981 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 59
Summary for Subcatchment 24S: Onsite Direct (3.57)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
1.810 55 Woods, Good, HSG B
1.760 61 Pasture/grassland/range, Good, HSG B
3.570 58 Weighted Average
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
12.6 48 0.0180 0.06 Sheet Flow, Sheet - Direct
Woods: Light underbrush n= 0.400 P2= 3.12"
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 60
Summary for Subcatchment 26S: OS-E to Pond (10.15)
Runoff = 0.17 cfs @ 3.80 hrs, Volume= 0.026 af, Depth= 0.03"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
10.150
75 1/4 acre lots,
38% imp, HSG B
Tc
Length
Slope
Velocity
Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
16.2
100
0.0150
0.10
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
5.0
1,254
0.0100
4.19
25.17
Channel Flow, Channel
Area= 6.0 sf Perim= 7.7' r= 0.78' n= 0.030
1.8
1,420
0.0200
13.34
94.33
Pipe Channel, Storm Sewer to Pond
36.0" Round Area= 7.1 sf Perim= 9.4' r= 0.75'
n= 0.013
23.0 2,774 Total
Subcatchment 26S: OS-E to Pond (10.15)
Hydrograph
■ Runoff
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 61
Summary for Subcatchment 27S: OS -SW (1.50)
Runoff = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Area (ac) CN Description
1.500 61 Pasture/grassland/range, Good, HSG B
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
10.2
100
0.0480
0.16
Sheet Flow, Sheet
Grass: Dense n= 0.240 P2= 3.12"
2.3
472
0.0440
3.38
Shallow Concentrated Flow, Shallow
Unpaved Kv= 16.1 fps
2.1
220
0.0077
1.78
Shallow Concentrated Flow, Gutter
Paved Kv= 20.3 fps
1.5
760
0.0200
8.41 14.86
Pipe Channel, Storm Sewer
18.0" Round Area= 1.8 sf Perim= 4.7' r= 0.38'
n= 0.013
16.1 1,552 Total
❑ Runoff
0
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 45 100
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 62
Summary for Pond 21 P: Prop Retention Pond
Inflow Area = 31.100 ac, Inflow Depth = 0.10" for WQ event
Inflow =
4.09 cfs @
3.27 hrs,
Volume=
0.247 of
Outflow =
0.09 cfs @
6.25 hrs,
Volume=
0.222 af, Atten= 98%, Lag= 178.9 min
Primary =
0.09 cfs @
6.25 hrs,
Volume=
0.222 of
Secondary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Tertiary =
0.00 cfs @
0.00 hrs,
Volume=
0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs / 3
Peak Elev= 589.52' @ 6.25 hrs Surf.Area= 27,882 sf Storage= 9,990 cf
Plug -Flow detention time= 1,449.7 min calculated for 0.222 of (90% of inflow)
Center -of -Mass det. time= 1,437.6 min ( 1,678.9 - 241.3 )
Volume Invert
#1 589.15'
UMMI1
Description
175,722 cf Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area
Inc.Store Cum.Store
(feet)
(sq-ft)
(cubic -feet) (cubic -feet)
589.15
25,475
0 0
589.50
27,720
9,309 9,309
590.00
31,022
14,686 23,995
591.00
34,268
32,645 56,640
592.00
37,348
35,808 92,448
593.00
41,165
39,257 131,704
594.00
46,871
44,018 175,722
Device Routing
Invert
Outlet Devices
#1 Primary
589.15'
2.5" Vert. Orifice/Grate C= 0.600
#2 Secondary
591.50'
30.0" W x 8.0" H Vert. Orifice/Grate X 3.00 C= 0.600
#3 Tertiary
593.50'
30.0' long x 5.0' breadth Broad -Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
2.50 3.00 3.50 4.00 4.50 5.00 5.50
Coef. (English) 2.34 2.50 2.70 2.68 2.68 2.66 2.65 2.65 2.65
2.65 2.67 2.66 2.68 2.70 2.74 2.79 2.88
Primary OutFlow Max=0.09 cfs @ 6.25 hrs HW=589.52' TW=0.00' (Dynamic Tailwater)
L1=Orifice/Grate (Orifice Controls 0.09 cfs @ 2.50 fps)
Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' TW=0.00' (Dynamic Tailwater)
L2=Orifice/Grate ( Controls 0.00 cfs)
Tertiary OutFlow Max=0.00 cfs @ 0.00 hrs HW=589.15' (Free Discharge)
L3= Broad -Crested Rectangular Weir ( Controls 0.00 cfs)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 63
Pond 21 P: Prop Retention Pond
Hydrograph
❑ Inflow
Outflow
Lia
Time (hours)

20131720 Wet Pond-final-6hr-v2 - As Built - 2019-06-1 Charlotte 6-hr 2-yr WQ Rainfall=1.00"
Prepared by Symanetc Printed 6/17/2019
HydroCAD® 10.00-15 s/n 03828 © 2015 HydroCAD Software Solutions LLC Page 64
Summary for Link 25L: Post Site Discharge
Inflow Area = 40.780 ac, Inflow Depth > 0.07" for WQ event
Inflow = 0.09 cfs @ 6.25 hrs, Volume= 0.222 of
Primary = 0.09 cfs @ 6.25 hrs, Volume= 0.222 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-100.00 hrs, dt= 0.02 hrs
N
U
3
0
LL
Link 25L: Post Site Discharge
Hydrograph
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Time (hours)
C Inflow
❑ Primary

APPENDIX B:
NC DENR Supplemental BMP Forms
Wet Pond Supplemental EMHT Calculation Worksheet

Permit No.
ae de pm—d dvowoJ
®' ' F P
NCDENR
STORMLYATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This tom must be filled out, printed and cubmilted.
The Requiied gems (PeR Chcou 1111) must be printed.tilledoW endsubmittedelongwith elloftherequired infoimalion.
I. PROJECT INFORMATION
Project name
Cowi at Marvin
Contact person
Robert Cash
Phonen umber
7o4548R-
Date
27�J—i4
Drainage area number
Project Site Development
II. DESIGN INFORMATION
Site characteristics
Drainage area
505,815 fl'
Impervious area, postdevelnpnrent
328,780 fl'
-A impervious
55.ofl %
Desgn rainfall depth
1.a In
Stange Volume: N—SAWaters
Hinimum volume required
Volume provided
Storage Volume: SAWaters
1.5" runoff volume
Pre -development 1-yr. 24-hr runoff
Past -development Pyr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calcul ions
Is the prelpost control of the 1 ph 24hr stami peak flow required?
1-yr, 24-hr rainfall depfi,
Rati lC, pra-developmem
Rational C, post-developmant
Rainfall Intensity: 1-yr, 24-hr stem,
Pre-develepmenc 1-yr, 24-hr peak flow
Post -development Pyr, 24-hr peak Aow
PrelPost Pyr, 24-hr peak flow control
Elevations
Temporary pool elei
Permanent pool elevation
SMNT elevation (aps— at file perm. pool eLuation)
Top of 1 flftvegetate-d shelf elevation
Betten, of IDI vegetated shelf elevation
Sediment cleanout top elevation (bottom of pond)
Sediment cleannut, bottom elevation
Sediment storage pmvided
26,766 fl'
61,169 fl' OK, volume provided is equal to or in excess of volume required.
fl'
fl'
fl'
f
y Nor N)
2.6 In
0.36 bnl lass)
0.60 (unitlaas)
3.10 Ini OK
3.16 felsec
32.H Wicec
29.50 fl'Isec
591.50 final
589.5fl final
In,sl
590.DU final
589.0fl final Data not needed for calculation option 41, but ON if provided.
581.Do final
580.0fl fin sl Data not needed mr calculatim, option 41, but ON epm role
1.0fl fl
Is there additional volume stored above the stateragwred camp. pooh
y Nor N)
Elevation of [he top of the additional volume
591.5 final OK
Surface Area.
Area, tanpomty Foal
34,851 fl'
suea REQUIRED, permanent pool
5 969 fl'
BACA ratio
1.18 (unitlesc)
Nee PROVIDED, permanentpool, Ar",,,, ,,t
23.323 It' CK
Area, bottom of 1 Oft vegetated shelf, AaLmur
17,755 fp
Area,sedimentdeanout,topelevationbottomofpond),A,,,,,,,
5,242 fl'
Volumes
Volume, temporary pool
51,150 fl' OK
Volume, permanent pool, Vp„„,_a,"t
119,800 fl'
Volume, forebay (sum of for=bays if more than one finebay)
22s1)9 fl'
Faraday%ofpennanent pool volume
19.0%% ON
SAIDA Table Data
Design TSS removal
85 %
Coastal 8AMA Table Used?
Nor N)
MountainlPiedmont BACA Table Used?
y Nor NJ
SAIDA 210
1.18 (unitlesc)
Average depth fused in 8AIDA table)_
Colaulah'on option 1 used? (See Figure 10-2b)
y N or N)Vduma,
pamanent pool, Vp­ '1
110,800 fl'
Nea provided, permanent pool An„„„„„u
23,323 fl'
Average depth calculated
7.00fl ON
Average depth used in SAIDA, dy. Round to nearesc0.5fl)
7.0fl OK
Calculation option 2 used? (see Figure 10-2b)
n N or M
Neer provided, permanent peal, A,,,,„�""i
23,323 ft
ea, bodom of 10fl vegetaLd shelf, Aa"�a,"u
17,755 If
Nea,sedimentdeanaut,topelevationbotlomofpond),
°aeon„a
5,242m
"Depth" (picture. bhv bottom of l OR shelf and top of sediment)
8.00fl
Average depth calculated
9.50fl OK
Average depth used In BACA, dam„IRoevd m ulv to nearest 3.5ft)
9.5it OK
Drawdown Calculation,
Drawdovm through orifice?
Disn'ter of orifice (if circular)
Neer ofcrifice (ikci,circular)
Coefficient of discharge (OU
Driving head (H„)
Dtowdown through weir?
Weir type
Coefficient of discharge (C,,)
Length of weir (L)
Driving head (H)
Pra•development 1-yr, 24-hr peak flow
Post -development Pyr, 24-hr peak flow
Sterage"dune dscharge rate (through discharge enfice or weir)
Storagevolune drawdoun, time
Additional lnfoimatian
Vegetated side dopes
Vegetated shdf slepe
Vegetated shelf width
Length of tlowpath to undo ratio
Length to width ratio
Trash rack for mail- & urn
FrearnsId provided
Veget,t d filter "'de"
Retarded drainage easement pravided2
Cepures all runoff at ultimate buddaut?
Drain mechanism for maintenance or am_egencies is.
y h`orN)
4.30 in
ini
0.60 bnitless)
1.83 fl
n or N)
In tlesc)
unitlesc)
fl
fl
3.16 fl'Isec
32.86 fl315ec
0. 27 rejea,
3.08 days OK, draws down in 2-5 days
a ON
1fl II ON
10.2. fl ON
3'1 ON
2.0 1 ON
y No'N) ON
1.0 fl ON
Ir N nr NJ Insuf(clenf. Vegetated filter required.
y'hu N ON
y N or N) OK

APPENDIX C:
Culvert Calculations

Culvert Report
Hydraflow Express Extension for AutoCADO Civil 3DO 2013 by Autodesk, Inc.
Ex. 24 in Culvert on Providence - 50 year event
Invert Elev Dn (ft)
Pipe Length (ft)
Slope (%)
Invert Elev Up (ft)
Rise (in)
Shape
Span (in)
No. Barrels
n-Value
Culvert Type
Culvert Entrance
Coeff. K,M,c,Y,k
Embankment
Top Elevation (ft)
Top Width (ft)
Crest Width (ft)
El- (R)
625.00
627.00
626.00
6226.00
624.00
623.00
622.00
621 00
620.00
619.00
= 620.94
= 37.40
= 1.98
= 621.68
= 24.0
= Circular
= 24.0
= 1
= 0.012
= Circular Concrete
= Square edge w/headwall (C)
= 0.0098, 2, 0.0398, 0.67, 0.5
= 627.22
= 24.00
= 100.00
Ex. 24 in Culvert on Providence - 50 yearevent
Circular Culr ert HGL Embank
Calculations
Qmin (cfs)
Qmax (cfs)
Tailwater Elev (ft)
Highlighted
Qtotal (cfs)
Qpipe (cfs)
Qovertop (cfs)
Veloc Dn (ft/s)
Veloc Up (ft/s)
HGL Dn (ft)
HGL Up (ft)
Hw Elev (ft)
Hw/D (ft)
Flow Regime
Wednesday, Jun 11 2014
= 32.00
= 38.00
_ (dc+D)/2
= 32.00
= 32.00
= 0.00
= 10.27
= 10.41
= 622.88
= 623.57
= 627.13
= 2.72
= Inlet Control
Hw Depth (ft)
6.32
5.32
4.32
3 32
2.32
1.32
0.32
-0 68
-1.68
-2.68
Reach (ft)

Culvert Report
Hydraflow Express Extension for AutoCADO Civil 3DO 2013 by Autodesk, Inc.
Prop. 36 in Culvert on Providence 50 yr
Invert Elev Dn (ft)
Pipe Length (ft)
Slope (%)
Invert Elev Up (ft)
Rise (in)
Shape
Span (in)
No. Barrels
n-Value
Culvert Type
Culvert Entrance
Coeff. K,M,c,Y,k
Embankment
Top Elevation (ft)
Top Width (ft)
Crest Width (ft)
El- (R)
625.0D
627 OD
626.OD
625.00
624 OD
623.0D
622.00
621.0D
620 0D
6f9.o0
613.00
= 619.56
= 63.39
= 3.75
= 621.94
= 36.0
= Circular
= 36.0
= 1
= 0.012
= Circular Concrete
= Groove end projecting (C)
= 0.0045, 2, 0.0317, 0.69, 0.2
= 627.22
= 24.00
= 100.00
Prop. 36 in Culvert - Providence 50 yr
Circular L.uW er1 HGL Embank
Calculations
Qmin (cfs)
Qmax (cfs)
Tailwater Elev (ft)
Highlighted
Qtotal (cfs)
Qpipe (cfs)
Qovertop (cfs)
Veloc Dn (ft/s)
Veloc Up (ft/s)
HGL Dn (ft)
HGL Up (ft)
Hw Elev (ft)
Hw/D (ft)
Flow Regime
Wednesday, Jul 23 2014
= 32.00
= 42.00
= (dc+D)/2
= 32.00
= 32.00
= 0.00
= 5.24
= 7.07
= 621.98
= 623.77
= 624.59
= 0.88
= Inlet Control
Hw Depth (ft)
6.D6
5 D6
4.06
3.06
206
1.06
0.06
-0.94
-1 94
-2.94
-3.94
Reach (ft)

Culvert Report
Hydraflow Express Extension for AutoCADO Civil 3DO 2013 by Autodesk, Inc.
Prop. 36 in Culvert on Providence 100 yr
Invert Elev Dn (ft)
Pipe Length (ft)
Slope (%)
Invert Elev Up (ft)
Rise (in)
Shape
Span (in)
No. Barrels
n-Value
Culvert Type
Culvert Entrance
Coeff. K,M,c,Y,k
Embankment
Top Elevation (ft)
Top Width (ft)
Crest Width (ft)
El- (R)
625.00
627 OD
626.OD
625.00
624 OD
623.00
622.00
621.0D
620 0D
6f9.00
613.00
= 619.56
= 63.39
= 3.75
= 621.94
= 36.0
= Circular
= 36.0
= 1
= 0.012
= Circular Concrete
= Groove end projecting (C)
= 0.0045, 2, 0.0317, 0.69, 0.2
= 627.22
= 24.00
= 100.00
Prop. 36 in Cu hart on Providence 100 yu
Circular L.uW er1 HGL Embank
Calculations
Qmin (cfs)
Qmax (cfs)
Tailwater Elev (ft)
Highlighted
Qtotal (cfs)
Qpipe (cfs)
Qovertop (cfs)
Veloc Dn (ft/s)
Veloc Up (ft/s)
HGL Dn (ft)
HGL Up (ft)
Hw Elev (ft)
Hw/D (ft)
Flow Regime
Wednesday, Jul 23 2014
= 32.00
= 42.00
= (dc+D)/2
= 36.50
= 36.50
= 0.00
= 5.84
= 7.45
= 622.04
= 623.90
= 624.83
= 0.96
= Inlet Control
Hw Depth (ft)
6.D6
5 D6
4.06
3.06
206
1.06
0.06
-0.94
-1 94
-2.94
-3.94
Reach (ft)

Culvert Report
Hydraflow Express Extension for AutoCADO Civil 3DO 2013 by Autodesk, Inc. Wednesday, Jul 23 2014
Prov Rd Driveway Culvert - FES5 to FES6 - 24 inch
Invert Elev Dn (ft)
= 624.76
Calculations
Pipe Length (ft)
= 22.88
Qmin (cfs)
= 11.00
Slope (%)
= 1.05
Qmax (cfs)
= 12.00
Invert Elev Up (ft)
= 625.00
Tailwater Elev (ft)
_ (dc+D)/2
Rise (in)
= 24.0
Shape
= Circular
Highlighted
Span (in)
= 24.0
Qtotal (cfs)
= 11.80
No. Barrels
= 1
Qpipe (cfs)
= 11.80
n-Value
= 0.013
Qovertop (cfs)
= 0.00
Culvert Type
= Circular Concrete
Veloc Dn (ft/s)
= 4.34
Culvert Entrance
= Square edge w/headwall (C)
Veloc Up (ft/s)
= 5.60
Coeff. K,M,c,Y,k
= 0.0098, 2, 0.0398, 0.67, 0.5
HGL Dn (ft)
= 626.38
HGL Up (ft)
= 626.27
Embankment
Hw Elev (ft)
= 626.88
Top Elevation (ft)
= 627.40
Hw/D (ft)
= 0.94
Top Width (ft)
= 20.00
Flow Regime
= Inlet Control
Crest Width (ft)
= 25.00
El- (R)
625.00
627.00
62600
625.00
624 OD
623.00
P— Rd Driveway Culvert - FE55 to FES6 - 24 inch
Circular CuW ert HGL Embank
H',, Depth (ftj
3.00
2.N
100
0.00
-100
-2.00
Reach (ft)