19-08 Modification 2020 - Narrative

CIS
ENGINEERING & ENVIRONMENTAL SCIENCE COMPANY
3008 ANDERSON DRIVE, SUITE 102
RALEIGH, NC 27609
[phone]
September 23, 2020
Mr. Warren Paschal
General Shale Brick, Inc.
300 Brick Plant Rd.
RECEIVED
Moncure, NC 27559
OCT 2 6 2020
Re: Erosion Control Evaluation
Mine Permit Modification
LAND QUALITY
MINING ROG
Brickhaven Mine #2 Tract B
JA
CAM
Permit No. 19-08
Chatham County, NC
Dear Mr. Paschal:
Engineering & Environmental Science Company (E2S) has completed the evaluation of the mine
renewal for the above -referenced mine. Separately submitted are the mine maps and application.
GENERAL PROJECT DISCUSSION
The Brickhaven Mine #2 Tract B (Permit No. 19-08) located in Chatham County, North Carolina,
contains 348 acres of permitted land (See Attachment, Vicinity Map). Currently, the permitted
allowable affected acreage is 94 acres. It is proposed to add an additional 50 acres of affected
acreage, for a total of 144 acres of allowable affected acreage. This additional acreage is located
within the mining permit limits, and no change to the total permitted area is proposed.
Mining will continue as permitted in the existing mine area, to the east of existing Basin K. Erosion
control for the proposed new mining area will consist of four (4) new sediment basins (Basins L, M,
N, and O). Earthen berms will be constructed to divert stormwater runoff to these basins. No mining
will occur north of the Progress Energy Easement that runs through the property.
After mining activities are complete, the disturbed areas will be sloped for positive drainage, re -
vegetated with grasses, and the erosion control structures will be removed. Some of the haul roads
will remain in -place to include from SR-1924 to the current stockpile areas. The ditches for these
roadways (if present) are presently grassed and stable. The buildings or sheds will be removed. The
5'x'5 concrete riser structure and outlet pipe at existing Basin K will remain in -place.

The two inactive spray irrigation systems' underground piping will remain in place or will be
excavated. The ends of the pipes will be capped if left in place. The nozzles and nozzle stands will
be removed.
EVALUATION
In accordance with the USDA Soil Survey of Chatham County, Peawick (PeA and PeB) is the
predominant soil type at the site (See Figure 2), and is classified as Hydrologic Group D.
The SCS TR-55 Method was used to calculate the 2-year, 10-year, and 25-year rain events. Erosion
control for the proposed mining area will consist of sediment basins with a riser/barrel system with
skimmers attached to the riser pipes. The proposed corrugated metal riser pipes will have skimmers
attached 1 ft. above the base of pipe. The system will drain the basins over a period of approximately
2-3 days.
Perimeter berms will be used to divert the stormwater runoff to the basins. Trash racks will be
provided for the CMP riser pipes. For each basin, a 20' wide secondary spillway is provided. The
secondary spillway is only activated for rain events greater than the 2-year rain event. The basins can
pass the 25-year rain event with one foot of freeboard. See Attachment B for calculations for these
basins.
CLOSURE
We appreciate serving General Shale Brick on this project. Please contact us if you have any
questions.
Sincerely,
TCAR04
T. Patrick Shillingto , E.0S II
President Q
Attachment A: Figures` 15472
Attachment B: Calculations �nrsi�
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RACK SNP'
FIS

Attachment A: Figures
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N
Scale: 1 2000'
pl�

1
.. WIG
1
t
WhID
O 1
PCB
_ - LldC
4 « r
z . • # yy�
Hydrological N
Soil Symbol Soil Name Group
WhD White Store D
CcB Carbonton C
MCC Mattadoni C Scale: 1" = 1000'
ENGINEERING & ENVIRONMENTAL
SCIENCE COMPANY
WhC White Store D
peg Peawick p
RALEIIGH, NORTH CAROLINA 27609
[phone]
PeA Peawick D
DATE:
Wh8 white Store D USDA Soil Survey
Brickhaven Mine #2 Tract B 9/23120
ChA Chewacla C Mine Permit No. 19-08 FIGURE NO
UdC Udorthents g Chatham Co., NC 2
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Attachment R: Calculations
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1S Alp
Watershed L
Subcat Reach on Link
Basin L

Basin L Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1 S: Watershed L
Runoff = 83.71 cfs @ 12.07 hrs, Volume= 5.769 af, Depth= 2.88"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 yr Rainfall=3.55"
Area (ac) CN Description
24.000
94 Newly
graded area, HSG D
24.000
100.00% Pervious Area
Tc Length
Slope
Velocity Capacity
Description
(min) (feet)
(ft/ft)
(ft/sec) (cfs)
3.2 100
0.0330
0.53
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
12.0 1,250
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
15.2 1,350 Total

Basin L Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: Basin L
Inflow Area = 24.000 ac, 0.00% Impervious, Inflow Depth = 2.88" for 2 yr event
Inflow = 83.71 cfs @ 12.07 hrs, Volume= 5.769 of
Outflow = 4.29 cfs @ 13.56 hrs, Volume= 5.769 af, Atten= 95%, Lag= 89.8 min
Primary = 4.29 cfs @ 13.56 hrs, Volume= 5.769 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 224.57' @ 13.56 hrs Surf.Area= 65,765 sf Storage= 159,325 cf
Plug -Flow detention time= 989.2 min calculated for 5.766 of (100% of inflow)
Center -of -Mass det. time= 990.9 min ( 1,779.9 - 789.0 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 255,968 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 57,800 0 0
223.00 60,896 59,348 59,348
224.00 63,992 62,444 121,792
225.00 67,088 65,540 187,332
226.00 70,184 68,636 255,968
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200 7' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 225.00' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary Out low Max=4.29 cfs @ 13.56 hrs HW=224.57' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.29 cfs @ 5.46 fps)
�2=18"
CMP Riser (Passes < 10.67 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway ( Controls 0.00 cfs)

Basin L Type 11 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1S: Watershed L
Runoff = 126.71 cfs @ 12.06 hrs, Volume= 8.952 af, Depth= 4.48"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 yr Rainfall=5.17"
Area (ac) CN Description
24.000
94 Newly
graded area, HSG D
24.000
100.00% Pervious Area
Tc Length
Slope
Velocity Capacity
Description
(min) (feet)
(ft/ft)
(ft/sec) (cfs)
3.2 100
0.0330
0.53
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
12.0 1,250
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
15.2 1,350 Total

Basin L Type // 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond 1 P: Basin L
Inflow Area = 24.000 ac, 0.00% Impervious, Inflow Depth = 4.48" for 10 yr event
Inflow = 126.71 cfs @ 12.06 hrs, Volume= 8.952 of
Outflow = 27.57 cfs @ 12.40 hrs, Volume= 8.951 af, Atten= 78%, Lag= 20.4 min
Primary = 27.57 cfs @ 12.40 hrs, Volume= 8.951 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 225.48' @ 12.40 hrs Surf.Area= 68,564 sf Storage= 220,048 cf
Plug -Flow detention time= 778.9 min calculated for 8.948 of (100% of inflow)
Center -of -Mass det. time= 780.8 min ( 1,558.4 - 777.5 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 255,968 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 57,800 0 0
223.00 60,896 59,348 59,348
224.00 63,992 62,444 121,792
225.00 67,088 65,540 187,332
226.00 70,184 68,636 255,968
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200 T Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 225.00' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary Out low Max=27.51 cfs @ 12.40 hrs HW=225.48' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.80 cfs @ 6.12 fps)
12=18" CMP Riser (Passes < 13.39 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 22.71 cfs @ 2.09 fps)

Basin L Type 11 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: Watershed L
Runoff = 152.49 cfs @ 12.06 hrs, Volume= 10.890 af, Depth= 5.45"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 yr Rainfall=6.15"
Area (ac) CN Description
24.000 94 Newly graded area, HSG D
24.000 100.00% Pervious Area
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
3.2
100
0.0330
0.53
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
12.0
1,250
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
15.2 1,350 Total

Basin L Type 11 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCADO 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 7
Summary for Pond 1 P: Basin L
Inflow Area = 24.000 ac, 0.00% Impervious, Inflow Depth = 5.45" for 25 yr event
Inflow = 152.49 cfs @ 12.06 hrs, Volume= 10.890 of
Outflow = 57.57 cfs @ 12.28 hrs, Volume= 10.890 af, Atten= 62%, Lag= 13.1 min
Primary = 57.57 cfs @ 12.28 hrs, Volume= 10.890 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 225.81' @ 12.28 hrs Surf.Area= 69,604 sf Storage= 243,102 cf
Plug -Flow detention time= 671.6 min calculated for 10.886 of (100% of inflow)
Center -of -Mass det. time= 673.5 min ( 1,446.3 - 772.8 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 255,968 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 57,800 0 0
223.00 60,896 59,348 59,348
224.00 63,992 62,444 121,792
225.00 67,088 65,540 187,332
226.00 70,184 68,636 255,968
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200 '/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 225.00' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow Max=57.17 cfs @ 12.28 hrs HW=225.81' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.98 cfs @ 6.34 fps)
�2=18" CMP Riser (Passes < 14.26 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 52.19 cfs @ 2.60 fps)

is —� 1p
Watershed M
S4
Reach on Lin
k
Basin M

Basin M Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: Watershed M
Runoff = 71.68 cfs @ 11.99 hrs, Volume= 3.997 af, Depth= 2.88"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 yr Rainfall=3.55"
Area (ac) CN Description
16.630 94 Newly graded area, HSG D
16.630 100.00% Pervious Area
Tc
Length
Slope
Velocity Capacity
Description
(min)
(feet)
(ft/ft)
(ft/sec) (cfs)
3.5
100
0.0250
0.47
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
4.9
510
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Neariv Bare & Until led Kv= 10.0 fps
8.4 610 Total

Basin M Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCADO 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: Basin M
Inflow Area = 16.630 ac, 0.00% Impervious, Inflow Depth = 2.88" for 2 yr event
Inflow = 71.68 cfs @ 11.99 hrs, Volume= 3.997 of
Outflow = 3.90 cfs @ 12.99 hrs, Volume= 3.997 af, Atten= 95%, Lag= 59.9 min
Primary = 3.90 cfs @ 12.99 hrs, Volume= 3.997 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 223.95' @ 12.99 hrs Surf.Area= 56,891 sf Storage= 105,550 cf
Plug -Flow detention time= 995.8 min calculated for 3.996 of (100% of inflow)
Center -of -Mass det. time= 997.3 min ( 1,780.0 - 782.7 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 51,200 0 0
223.00 54,116 52,658 52,658
224.00 57,032 55,574 108,232
225.00 59,948 58,490 166,722
226.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200 '/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 224.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow, Max=3.90 cfs @ 12.99 hrs HW=223.95' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 3.90 cfs @ 4.97 fps)
2=18" CMP Riser (Passes < 8.30 cfs potential flow)
t3=4"
Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway ( Controls 0.00 cfs)

Basin M Type 11 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1 S: Watershed M
Runoff = 108.19 cfs @ 11.99 hrs, Volume= 6.203 af, Depth= 4.48"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 yr Rainfall=5.17"
Area (ac) CN Description
16.630
94 Newly
graded area, HSG D
16.630
100.00% Pervious Area
Tc Length
Slope
Velocity Capacity
Description
(min) (feet)
(ft/ft)
(ft/sec) (cfs)
3.5 100
0.0250
0.47
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
4.9 510
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
8.4 610 Total

Basin M Type/1 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond 1 P: Basin M
Inflow Area = 16.630 ac, 0.00% Impervious, Inflow Depth = 4.48" for 10 yr event
Inflow = 108.19 cfs @ 11.99 hrs, Volume= 6.203 of
Outflow = 24.37 cfs @ 12.20 hrs, Volume= 6.203 af, Atten= 77%, Lag= 12.4 min
Primary = 24.37 cfs @ 12.20 hrs, Volume= 6.203 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 224.69' @ 12.20 hrs Surf.Area= 59,040 sf Storage= 148,507 cf
Plug -Flow detention time= 725.1 min calculated for 6.200 of (100% of inflow)
Center -of -Mass det. time= 726.7 min ( 1,498.0 - 771.2 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 51,200 0 0
223.00 54,116 52,658 52,658
224.00 57,032 55,574 108,232
225.00 59,948 58,490 166,722
226.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200 '/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 224.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary Out low Max=24.33 cfs @ 12.20 hrs HW=224.69' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.36 cfs @ 5.55 fps)
2=18" CMP Riser (Passes < 11.06 cfs potential flow)
13=4"
Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 19.97 cfs @ 2.01 fps)

Basin M Type/1 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: Watershed M
Runoff = 130.08 cfs @ 11.99 hrs, Volume= 7.546 af, Depth= 5.45"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 yr Rainfall=6.15"
Area (ac) CN Description
16.630
94 Newly
graded area, HSG D
16.630
100.00% Pervious Area
Tc Length
Slope
Velocity Capacity
Description
(min) (feet)
(ft/ft)
(ft/sec) (cfs)
3.5 100
0.0250
0.47
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
4.9 510
0.0300
1.73
Shallow Concentrated Flow, Shallow Concent.
Nearly Bare & Untilled Kv= 10.0 fps
8.4 610 Total

Basin M Type 1124-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Pape 7
Summary for Pond 1 P: Basin M
Inflow Area = 16.630 ac, 0.00% Impervious, Inflow Depth = 5.45" for 25 yr event
Inflow = 130.08 cfs @ 11.99 hrs, Volume= 7.546 of
Outflow = 51.68 cfs @ 12.13 hrs, Volume= 7.546 af, Atten= 60%, Lag= 8.3 min
Primary = 51.68 cfs @ 12.13 hrs, Volume= 7.546 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 225.01' @ 12.13 hrs Surf.Area= 59,973 sf Storage= 167,250 cf
Plug -Flow detention time= 621.4 min calculated for 7.546 of (100% of inflow)
Center -of -Mass det. time= 621.1 min ( 1,387.6 - 766.5 )
Volume Invert Avail.Storage Storage Description
#1 222.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
222.00 51,200 0 0
223.00 54,116 52,658 52,658
224.00 57,032 55,574 108,232
225.00 59,948 58,490 166,722
226.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 221.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 221.00' / 220.00' S= 0.0200'/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 223.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 222.00' 0.230 cfs 4" Skimmer
#4 Primary 224.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow Max=51.05 cfs @ 12.13 hrs HW=225.00' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.54 cfs @ 5.78 fps)
�2=18"
CMP Riser (Passes < 12.04 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 46.51 cfs @ 2.52 fps)

Watershed N
Su4
Reach on Link
Basin N

Basin N Type Il 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: Watershed N
Runoff = 70.39 cfs @ 12.00 hrs, Volume= 4.031 af, Depth= 2.88"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 yr Rainfall=3.55"
Area (ac) CN Description
16.770
94 Newly
graded area, HSG D
16.770
100.00% Pervious Area
Tc Length
Slope
Velocity Capacity
Description
(min) (feet)
(ft/ft)
(ft/sec) (cfs)
3.9 100
0.0200
0.43
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
5.2 630
0.0400
2.00
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
9.2 730 Total

Basin N Type 1124-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here) Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: Basin N
Inflow Area = 16.770 ac, 0.00% Impervious, Inflow Depth = 2.88" for 2 yr event
Inflow = 70.39 cfs @ 12.00 hrs, Volume= 4.031 of
Outflow = 3.91 cfs @ 13.01 hrs, Volume= 4.031 af, Atten= 94%, Lag= 60.6 min
Primary = 3.91 cfs @ 13.01 hrs, Volume= 4.031 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 230.97' @ 13.01 hrs Surf.Area= 56,943 sf Storage= 106,537 cf
Plug -Flow detention time= 990.7 min calculated for 4.029 of (100% of inflow)
Center -of -Mass det. time= 992.2 min ( 1,775.6 - 783.4 )
Volume Invert Avail.Storage Storage Description
#1 229.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
229.00 51,200 0 0
230.00 54,116 52,658 52,658
231.00 57,032 55,574 108,232
232.00 59,948 58,490 166,722
233.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 228.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 228.00' / 227.00' S= 0.0200 T Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 230.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 229.00' 0.230 cfs 4" Skimmer
#4 Primary 231.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary Out low Max=3.91 cfs @ 13.01 hrs HW=230.97' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 3.91 cfs @ 4.98 fps)
�__3=4"
2=18" CMP Riser (Passes < 8.38 cfs potential flow)
Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway ( Controls 0.00 cfs)

Basin N Type 11 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 ©2017 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1S: Watershed N
Runoff = 106.30 cfs @ 12.00 hrs, Volume= 6.255 af, Depth= 4.48"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 yr Rainfall=5.17"
Area (ac) CN Description
16.770 94 Newly graded area, HSG D
16.770 100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
3.9
100
0.0200
0.43
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
5.2
630
0.0400
2.00
Shallow Concentrated Flow, Shallow Concent.
Nearly Bare & Untilled Kv= 10.0 fps
9.2 730 Total

Basin N Type 11 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCADO 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond 1 P: Basin N
Inflow Area = 16.770 ac, 0.00% Impervious, Inflow Depth = 4.48" for 10 yr event
Inflow = 106.30 cfs @ 12.00 hrs, Volume= 6.255 of
Outflow = 25.17 cfs @ 12.21 hrs, Volume= 6.255 af, Atten= 76%, Lag= 12.8 min
Primary = 25.17 cfs @ 12.21 hrs, Volume= 6.255 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 231.70' @ 12.21 hrs Surf.Area= 59,072 sf Storage= 149,159 cf
Plug -Flow detention time= 720.2 min calculated for 6.252 of (100% of inflow)
Center -of -Mass det. time= 721.8 min ( 1,493.8 - 772.0)
Volume Invert Avail.Storage Storage Description
#1 229.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
229.00 51,200 0 0
230.00 54,116 52,658 52,658
231.00 57,032 55,574 108,232
232.00 59,948 58,490 166,722
233.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 228.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 228.00' / 227.00' S= 0.0200 7' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 230.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 229.00' 0.230 cfs 4" Skimmer
#4 Primary 231.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow Max=24.95 cfs @ 12.21 hrs HW=231.70' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.37 cfs @ 5.56 fps)
2=18" CMP Riser (Passes < 11.08 cfs potential flow)
13=4"
Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 20.59 cfs @ 2.03 fps)

Basin N Type lI 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1S: Watershed N
Runoff = 127.83 cfs @ 12.00 hrs, Volume= 7.610 af, Depth= 5.45"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 yr Rainfall=6.15"
Area (ac) CN Description
16.770 94 Newly graded area, HSG D
16.770 100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
3.9
100
0.0200
0.43
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
5.2
630
0.0400
2.00
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
9.2 730 Total

Basin N Type 11 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 7
Summary for Pond 1 P: Basin N
Inflow Area = 16.770 ac, 0.00% Impervious, Inflow Depth = 5.45" for 25 yr event
Inflow = 127.83 cfs @ 12.00 hrs, Volume= 7.610 of
Outflow = 52.21 cfs @ 12.15 hrs, Volume= 7.61Oaf, Atten= 59%, Lag= 8.8 min
Primary = 52.21 cfs @ 12.15 hrs, Volume= 7.610 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 232.01' @ 12.15 hrs Surf.Area= 59,988 sf Storage= 167,562 cf
Plug -Flow detention time= 617.2 min calculated for 7.610 of (100% of inflow)
Center -of -Mass det. time= 617.0 min ( 1,384.2 - 767.2 )
Volume Invert Avail.Storage Storage Description
#1 229.00' 228,128 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
229.00 51,200 0 0
230.00 54,116 52,658 52,658
231.00 57,032 55,574 108,232
232.00 59,948 58,490 166,722
233.00 62,864 61,406 228,128
Device Routing Invert Outlet Devices
#1 Primary 228.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 228.00' / 227.00' S= 0.02007' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 230.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 229.00' 0.230 cfs 4" Skimmer
#4 Primary 231.25' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
PrimautFlow Max=51.97 cfs @ 12.15 hrs HW=232.01' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.55 cfs @ 5.79 fps)
�2=18"
CMP Riser (Passes < 12.07 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 47.42 cfs @ 2.54 fps)

ls)� Alp
Watershed O
Subcat Reach on Link
Basin O

Basin O Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 02017 HydroCAD Software Solutions LLC Page 2
Summary for Subcatchment 1S: Watershed O
Runoff = 55.29 cfs @ 12.05 hrs, Volume= 3.541 af, Depth= 2.68"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 2 yr Rainfall=3.55"
Area (ac) CN Description
13.950
94 Newly graded area, HSG D
1.880
80 >75% Grass cover, Good, HSG D
15.830
92 Weighted Average
15.830
100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
3.9
100
0.0200
0.43
Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
9.6
1,060
0.0340
1.84
Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
13.5 1,160 Total

Basin O Type 11 24-hr 2 yr Rainfall=3.55"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 3
Summary for Pond 1 P: Basin O
Inflow Area = 15.830 ac, 0.00% Impervious, Inflow Depth = 2.68" for 2 yr event
Inflow = 55.29 cfs @ 12.05 hrs, Volume= 3.541 of
Outflow = 4.04 cfs @ 12.92 hrs, Volume= 3.541 af, Atten= 93%, Lag= 52.5 min
Primary = 4.04 cfs @ 12.92 hrs, Volume= 3.541 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 219.17' @ 12.92 hrs Surf.Area= 44,432 sf Storage= 88,939 cf
Plug -Flow detention time= 700.7 min calculated for 3.540 of (100% of inflow)
Center -of -Mass det. time= 701.8 min ( 1,499.7 - 797.8 )
Volume Invert Avail.Storage Storage Description
#1 217.00' 175,241 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
217.00 38,000 0 0
218.00 40,297 39,149 39,149
219.00 43,915 42,106 81,255
220.00 46,975 45,445 126,700
221.00 50,107 48,541 175,241
Device Routing Invert Outlet Devices
#1 Primary 216.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 216.00' / 215.00' S= 0.0200 7' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 218.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 217.00' 0.230 cfs 4" Skimmer
#4 Primary 219.50' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary Out low Max=4.04 cfs @ 12.92 hrs HW=219.17' (Free Discharge)
1=12" CMP Barrel (Barrel Controls 4.04 cfs @ 5.15 fps)
�2=118"
CMP Riser (Passes < 9.20 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway ( Controls 0.00 cfs)

Basin O Type 11 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 1S: Watershed O
Runoff = 85.43 cfs @ 12.05 hrs, Volume= 5.614 af, Depth= 4.26"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 10 yr Rainfall=5.17"
Area (ac) CN Description
13.950 94 Newly graded area, HSG D
1.880 80 >75% Grass cover, Good, HSG D
15.830 92 Weighted Average
15.830 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.9 100 0.0200 0.43 Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
9.6 1,060 0.0340 1.84 Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
13.5 1,160 Total

Basin O Type/1 24-hr 10 yr Rainfall=5.17"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond 1 P: Basin O
Inflow Area = 15.830 ac, 0.00% Impervious, Inflow Depth = 4.26" for 10 yr event
Inflow = 85.43 cfs @ 12.05 hrs, Volume= 5.614 of
Outflow = 26.51 cfs @ 12.28 hrs, Volume= 5.614 af, Atten= 69%, Lag= 13.7 min
Primary = 26.51 cfs @ 12.28 hrs, Volume= 5.614 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 219.97' @ 12.28 hrs Surf.Area= 46,872 sf Storage= 125,165 cf
Plug -Flow detention time= 511.7 min calculated for 5.611 of (100% of inflow)
Center -of -Mass det. time= 512.9 min ( 1,298.2 - 785.3 )
Volume Invert Avail.Storage Storage Description
#1 217.00' 175,241 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
217.00 38,000 0 0
218.00 40,297 39,149 39,149
219.00 43,915 42,106 81,255
220.00 46,975 45,445 126,700
221.00 50,107 48,541 175,241
Device Routing Invert Outlet Devices
#1 Primary 216.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 216.00' / 215.00' S= 0.0200'/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 218.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 217.00' 0.230 cfs 4" Skimmer
#4 Primary 219.50' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow Max=26.32 cfs @ 12.28 hrs HW=219.96' (Free Discharge)
196
12" CMP Barrel (Barrel Controls 4.52 cfs @ 5.76 fps)
-2=18" CMP Riser (Passes < 11.92 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 21.80 cfs @ 2.06 fps)

Basin O Type 11 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD®10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 1 S: Watershed O
Runoff = 103.49 cfs @ 12.05 hrs, Volume= 6.882 af, Depth= 5.22"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Type II 24-hr 25 yr Rainfall=6.15"
Area (ac) CN Description
13.950 94 Newly graded area, HSG D
1.880 80 >75% Grass cover, Good, HSG D
15.830 92 Weighted Average
15.830 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
3.9 100 0.0200 0.43 Sheet Flow, Sheet
Fallow n= 0.050 P2= 3.55"
9.6 1,060 0.0340 1.84 Shallow Concentrated Flow, Shallow Concent.
Nearlv Bare & Untilled Kv= 10.0 fps
13.5 1,160 Total

Basin O Type 1l 24-hr 25 yr Rainfall=6.15"
Prepared by {enter your company name here} Printed 10/26/2020
HydroCAD® 10.00-20 s/n 07329 © 2017 HydroCAD Software Solutions LLC Page 7
Summary for Pond 1 P: Basin O
Inflow Area = 15.830 ac, 0.00% Impervious, Inflow Depth = 5.22" for 25 yr event
Inflow = 103.49 cfs @ 12.05 hrs, Volume= 6.882 of
Outflow = 51.13 cfs @ 12.21 hrs, Volume= 6.882 af, Atten= 51 %, Lag= 9.6 min
Primary = 51.13 cfs @ 12.21 hrs, Volume= 6.882 of
Routing by Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.05 hrs
Peak Elev= 220.25' @ 12.21 hrs Surf.Area= 47,762 sf Storage= 138,902 cf
Plug -Flow detention time= 437.4 min calculated for 6.879 of (100% of inflow)
Center -of -Mass det. time= 438.6 min ( 1,218.6 - 779.9 )
Volume Invert Avail.Storage Storage Description
#1 217.00' 175,241 cf Custom Stage Data (Prismatic) Listed below
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic -feet) (cubic -feet)
217.00 38,000 0 0
218.00 40,297 39,149 39,149
219.00 43,915 42,106 81,255
220.00 46,975 45,445 126,700
221.00 50,107 48,541 175,241
Device Routing Invert Outlet Devices
#1 Primary 216.00' 12.0" Round 12" CMP Barrel
L= 50.0' CMP, projecting, no headwall, Ke= 0.900
Inlet / Outlet Invert= 216.00' / 215.00' S= 0.0200 '/' Cc= 0.900
n= 0.025 Corrugated metal, Flow Area= 0.79 sf
#2 Device 1 218.00' 18.0" Horiz. 18" CMP Riser C= 0.600
Limited to weir flow at low heads
#3 Device 1 217.00' 0.230 cfs 4" Skimmer
#4 Primary 219.50' 20' Secondary Spillway, C= 3.27
Offset (feet) 0.00 4.50 24.50 29.00
Height (feet) 1.50 0.00 0.00 1.50
Primary OutFlow Max=50.72 cfs @ 12.21 hrs HW=220.25' (Free Discharge)
�12" CMP Barrel (Barrel Controls 4.68 cfs @ 5.96 fps)
'=18" CMP Riser (Passes < 12.76 cfs potential flow)
3=4" Skimmer (Passes < 0.23 cfs potential flow)
=20' Secondary Spillway (Weir Controls 46.04 cfs @ 2.52 fps)