Weatherspoon CBE - Appendix C_20191230

Wood Environmental & Infrastructure Solutions, Inc. Wood
Duke Energy Coal Combustion Residuals Management Program
Weatherspoon Station Basin CAMA Closure Plan
APPENDIX C - Engineering Evaluations and
Analysis

wood.
March 28, 2019
Mr. Dale Smith
Project Manager
Duke Energy
526 South Church Street
Charlotte, North Carolina 28202
Subject: Weatherspoon 1979 Ash Pond H&H Update
Summary of Supporting H&H Analyses
Duke Energy — WH Weatherspoon Steam Station
Robeson County, North Carolina
Wood E&IS Project No. 7812-19-0141
Dear Mr. Smith,
As authorized by Duke Energy Carolinas, LLC (Duke Energy), Wood Environment & Infrastructure
Solutions, Inc. (Wood E&IS) has revised the Hydraulic and Hydrologic analysis (H&H) based upon
a full Probable Maximum Precipitation (PMP) rainfall event to determine if the ash basins located
at the WH Weatherspoon Steam Station have sufficient capacity for the design storm with the
current outlet conditions.
Background Information
The Weatherspoon Plant is located at 491 Power Plant Road near Lumberton, North Carolina.
The Plant contained three retired coal-fired units that operated from 1949 until electricity
generation from the coal-fired units ceased in 2011. In February 2012, the three coal-fired units
were retired. Pumping to the basin (primarily stormwater) was terminated in 2012. Demolition
of the Weatherspoon Plant was completed in 2016. The WH Weatherspoon Steam Plant is
permanently retired from service and ash sluice flow is no longer discharged into the Ash Pond.
The 1979 Ash Pond (ROBES-009) has been used to store coal combustion residuals (CCR)
that were sluiced to and deposited into the holding and settling basin. The materials pumped to
the basin primarily consisted of fly ash, bottom ash, coal slag, unburned coal, and stormwater
from the plant. The ash basin is a single perimeter unit, with multiple internal units constructed
for basin management and wastewater treatment. There are no longer any ash disposal
Correspondence:
Wood Environment &Infrastructure Solutions, Inc.
4021 Stirrup Creek Drive, Suite 100
Durham, North Carolina 27703
Tel [phone]
Fax [phone]
0
Licensure NC Engineering F-1253 NC Geology C-247

Duke Energy
March 28, 2019
Page 2
Weatherspoon Steam Station
Weatherspoon 1979 Ash Pond H&H Update
Wood E&IS Project No. 7812-19-0141
operations within the Ash Pond areas with the permanent retirement of the fossil generating
units.
The 1979 Ash Pond, herein referred to as the Ash Pond, is located east of the plant site which is
adjacent to the Lumber River. From review of available historical descriptive information, this
Ash Pond has a surface area of about 56 acres, maximum dike height of 28 feet, crest width of
12 feet, and crest level elevation of approximately 143 feet. The dike length is approximately
6,600 feet. The upstream (interior) slope is reported to be about 2 (horizontal):1 (vertical) and
the downstream (exterior) slope is reported to be in the range of 2.5:1 to 1.5:11.
The main pond area has a 24-inch RCP riser/outlet structure that empties into a secondary
settling basin; then thru a second 24-inch RCP riser/outlet structure that discharges into a
receiving ditch that flows into the cooling lake. Based on general observation, these structures
appear to be in working order, but the water level in the main basin is well below the riser crest
elevation with little or no water present.
Active excavation of the ash within the basin for beneficial reuse has been ongoing since
September 2017. As of March 12, 2019, approximately 380,860 tons of ash has transported
from the site for beneficial reuse.
The Weatherspoon ash basin has operated under a National Pollutant Discharge Elimination
System (NPDES) permit number NC0005363 issued by the North Carolina Department of
Environmental Quality (NCDEQ) as a water treatment unit. The basin exterior embankment is
regulated by NCDEQ Division of Energy, Mineral and Land Resources, Land Quality Section,
Dam Safety Program as a High Hazard Dam and is identified in the regulatory program as
"Weatherspoon Ash Pond Dam" (State I.D. No. ROBES-009).
H&H Evaluation Criteria
North Carolina's Department of Environmental Quality (NCDEQ) Dam Safety has adopted the
Federal CCR Rule and per the dam safety High Hazard Classification, each ash basin is now
required to pass a full Probable Maximum Precipitation (PMP). Each basin is classified as high
hazard by NCDEQ due to the potential for environmental impacts greater than $200,000, if the
basin failed.
The computer program HydroCAD Version 10.0 was initially used to perform the H&H calculations
to determine if the current conditions (revised per updated survey information) could safely store
the revised design storm (full PMP storm event) without an uncontrolled discharge. Previously,
the design storm was listed as the '/2 PMP storm event. NCDEQ has requested that the
supporting modeling information be provided in HEC-RAS/HMS format.
The existing conditions for the Ash Pond was obtained from best available reports and
topographic data including the Wood E&IS Hydrologic and Hydraulic Evaluation Weatherspoon
Ash Ponds, McKim and Creed Topographic Survey (2014, 2018), and LiDAR Topographic Survey
by WSP (2015).
The Weatherspoon Ash Pond is classified as high hazard, with the revised regulatory design
storm for the ponds of the full PMP storm event. Based on the Hydrometeorological Report No.
51, Probable Maximum Precipitation Estimates, United States East of the 105th Meridian, from

Duke Energy Weatherspoon Steam Station
March 28, 2019 Weatherspoon 1979 Ash Pond H&H Update
Page 3 Wood E&IS Project No. 7812-19-0141
the National Oceanic and Atmospheric Administration (Figure 18: All -Season PMP (in.) for 6 hour,
10 mil) the PMP for the Weatherspoon site is as follows:
• PMP = 30.2 inches of rainfall for 6 hours
Based on field observations and aerial imagery, the basin was assigned appropriate curve
numbers (CN) for the general condition of land covers with an appropriate time of concentration
calculated for each area by using TR-55 recommendations.
The storage for the basin was developed from the assumed initial water elevation to the top of
dam. The storage for the basin was estimated using the prismatic volume calculation method
with the elevation -surface area input data. Storage volumes were determined from contours
derived from the updated topographic surveys. Additional ponding area details can be found in
the modeling results.
The H&H Analysis was conducted for the proposed stage -storage conditions and Table 1 provides
information on the current outlet structures. The H&H Analyses were conducted for the stage -
storage conditions. The 1979 Ash Pond has an active pumping system associated with the ash
removal project, that generally keeps the pond pumped down to the minimum permissible depth
(approximately 3 feet in the deepest area of the basin).
Table 1. 1979 Ash Pond Outlet Existing Conditions
1979 Ash Pond
Characteristic
Main Pond
Polishing Pond
Dike Crest Elevation (ft)
143.6
143.8
Culvert Diameter (in)
Weir
22.5
Riser Elevation (ft)
140.3
132.95
Culvert Material
Geogrid
RCP (with CIPP lining)
The settling pond outlets into the cooling pond. The basin is partially filled with ash, and
stormwater would likely infiltrate into the underlying ash material during a storm event. For the
purpose of this calculation, a curve number (CN) for pond surfaces of 98 was assumed. A
minimum time of concentration (Tc) was calculated for the pond consistent with T-55 methods in
HydroCAD. The length of the flow paths of sheet flow, shallow concentrated flow, and channel
flow as well as slope and channel characteristics were determined based on the topography,
which is consistent with TR-55 recommendations. Note that conditions are rapidly changing due
to the ash excavation and removal project, and results of the analysis are based upon conditions
as determined by the last topographic survey completed at the site. Additional details on time of
concentration for each pond can be found in the modeling HydroCAD results. The storage for
each basin was estimated using the prismatic volume calculation method with the elevation -
surface area input data. Storage volumes for the 1979 Ash Pond were determined from contours
derived from McKim and Creed Topographic Survey (2014, 2018), and WSP LIDAR Topography

Duke Energy Weatherspoon Steam Station
March 28, 2019 Weatherspoon 1979 Ash Pond H&H Update
Page 4 Wood E&IS Project No. 7812-19-0141
Survey (2014). Additional ponding area details can be found in the modeling results. Wood E&IS
assumed a Type II storm distribution for the 6-hr peak hydrograph.
In order to support the request by NCDEQ to model the basin in HEC-RAS/HMS format, the
existing hydraulic models created in HydroCAD were re-created using USACE HEC-RAS version
5.0 or HEC-HMS version 4.3. The HEC-RAS/HMS models were developed using inputs from the
existing HydroCAD models to the greatest extent possible. At a minimum, the following inputs
required for the development of the HEC-RAS/HMS model were utilized:
• Inflow hydrographs
• Stage -Storage rating curves for the ash ponds
• Outlet rating curves
Where appropriate, the ash ponds were represented as Storage Areas. The Stage -Storage
relationship used as input into the HydroCAD model was applied to represent the volume in the
basins. For the majority of the sites, where the ash pond water surface elevation is controlled by
a single outlet structure, the stage versus flowrate rating curve calculated in HydroCAD was
applied to the HEC-RAS/HMS model as a Storage Area Connection. The storage area
connection was connected to either another Storage Area or a 1 D river reach long enough to
reflect a normal depth hydraulic condition. It is assumed that there are no tailwater impacts and
that the receiving Storage Area or 1 D Channel does not impact the outflow from the basin of
interest. For the more hydraulically complex basins, the outlet structures (weirs orifices, and
culverts) were incorporated into the model to account for any tailwater or reverse flows. The HEC-
RAS/HMS model was run in as an unsteady model, with the inflow inputs to the model as lateral
inflow hydrographs. The hydrographs were consistent with those generated from the HydroCAD
models, and it is assumed that new/additional hydrologic modeling will not be required.
H&H Summary
Using the information above and the design storm hydrograph, Wood E&IS completed the H&H
Analyses running the models for 160 hours (6.7 days). Results of the analyses are shown below
in Table 2. Analysis of the current conditions indicate that the 1979 Ash Pond has the ability to
contain the design storm (PMP storm event) and passes the inflow volume through pumping
operations.

Duke Energy Weatherspoon Steam Station
March 28, 2019 Weatherspoon 1979 Ash Pond H&H Update
Page 5 Wood E&IS Project No. 7812-19-0141
Table 2. Modeling Results
Updated Results
Main Ash Pond
Full PMP Storm Event
Polishing Pond
Full PMP Storm Event
Peak Stage during OF (ft)
141.1
138.5
Dike Elevation (ft)
143.6
143.8
Pond Freeboard (ft)
2.5
5.3
100% Inflow Volume (acre-ft)
23.8
25.3
80% Inflow Volume (acre-ft)
19.0
20.2
(Minimum) 80% Discharge Time (hr)
23.0
21.6
According to Dam Safety 15A NCAC 2K.0205, the spillway system shall be capable of removing
at least 80 percent of the water temporarily detained above the elevation of the primary spillway
within 15 days following passage of the design storm peak. Based upon the existing conditions,
the Main Ash Basin safely stores and passes the design storm event, with flow entering the
Polishing Pond. The existing conditions release more than 80% of the inflow to the Main Ash
Basin within 15 days after the design storm begins. The Polishing Pond safely stores and passes
the design storm event, with flow entering the Cooling Lake. The existing conditions release more
than 80% of the inflow to the Polishing Pond within 15 days after the design storm begins. Thus,
the current structures are compliant with 15A NCAC 2K.0205. The results for the calculations are
attached.
Conclusion
Based on the results of this study and considering the conservative assumption made (no
infiltration) Wood E&IS concludes the existing conditions for the 1979 Ash Pond will safely pass
the design storm (full PMP storm event) without an uncontrolled discharge and meets the
drawdown requirements per 15A NCAC 2K 0.0205.
Closing
Wood E&IS appreciates the opportunity to offer our services on this project. If you have
any questions concerning this response, please contact us.

Duke Energy
March 28, 2019
Page 6
Sincerely,
Wood Environment & Infrastructure Solutions, Inc.
William A. Williams, PE, PG
Senior Engineer
HEC-RAS/HMS model provided separately
Weatherspoon Steam Station
Weatherspoon 1979 Ash Pond H&H Update
Wood E&IS Project No. 7812-19-0141
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lSfrda id [i;-A
Jeffery Mann, PE
Chief Engineer

wood.
October 11, 2019
Mr. Dale Smith
Project Manager
Duke Energy
526 South Church Street
Charlotte, North Carolina 28202
Subject: Hydrology and Hydraulics Analysis Summary Report
Weatherspoon Ash Basin Decommissioning
Duke Energy — Weatherspoon Steam Station
Lumberton County, North Carolina
Wood Project No. 7812180072
Dear Mr. Smith,
As part of the decommissioning plan for the Weatherspoon Ash Basin, Wood Environment &
Infrastructure Solutions, Inc. (Wood) has prepared this Hydraulic and Hydrologic analysis (H&H)
summary report. This H&H summary represents the Weatherspoon Ash Basin in the proposed
decommissioned condition.
Background Information
The Weatherspoon Plant is located at 491 Power Plant Road near Lumberton, North Carolina.
The Plant contained three retired coal-fired units that operated from 1949 until electricity
generation from the coal-fired units ceased in 2011. In February 2012, the three coal-fired units
were retired. Pumping to the basin (primarily stormwater) was terminated in 2012. Demolition of
the Weatherspoon Plant was completed in 2016. The WH Weatherspoon Steam Plant is
permanently retired from service and ash sluice flow is no longer discharged into the Ash Pond.
The 1979 Ash Pond (ROBES-009) has been used to store coal combustion residuals (CCR) that
were sluiced to and deposited into the holding and settling basin. The materials pumped to the
basin primarily consisted of fly ash, bottom ash, coal slag, unburned coal, and stormwater from
the plant. The ash basin is a single perimeter unit, with multiple internal units constructed for
basin management and wastewater treatment. There are no longer any ash disposal operations
within the Ash Pond areas with the permanent retirement of the fossil generating units.
The 1979 Ash Pond, herein referred to as the Ash Pond, is located east of the plant site which is
adjacent to the Lumber River. From review of available historical descriptive information, this Ash
Pond has a surface area of about 56 acres, maximum dike height of 28 feet, crest width of 12
Wood Environment & Infrastructure Solutions, Inc.
4021 Stirrup Creek Drive, Suite 100
Durham, North Carolina 27703
Tel [phone]
Fax [phone]
www.woodpic.com
Licensure: NC Engineering F-1253 NC Geology C-247
n
LJ

Duke Energy Weatherspoon Station
October 11, 2019 Hydrology and Hydraulics Analysis Summary Report
Page 2 Wood Project No. 7812180072
feet, and crest level elevation of approximately 143 feet. The dike length is approximately 6,600
feet. The upstream (interior) slope is reported to be about 2 (horizontal):1 (vertical) and the
downstream (exterior) slope is reported to be in the range of 2.5:1 to 1.5:11.
The main pond area has a 24-inch RCP riser/outlet structure that empties into a secondary settling
basin; then thru a second 24-inch RCP riser/outlet structure that discharges into a receiving ditch
that flows into the cooling lake. Based on general observation, these structures appear to be in
working order, but the water level in the main basin is well below the riser crest elevation with little
or no water present.
Active excavation of the ash within the basin for beneficial reuse has been ongoing since
September 2017. As of March 12, 2019, approximately 380,860 tons of ash has transported from
the site for beneficial reuse.
The Weatherspoon ash basin has operated under a National Pollutant Discharge Elimination
System (NPDES) permit number NC0005363 issued by the North Carolina Department of
Environmental Quality (NCDEQ) as a water treatment unit. The basin exterior embankment is
regulated by NCDEQ Division of Energy, Mineral and Land Resources, Land Quality Section,
Dam Safety Program as a High Hazard Dam and is identified in the regulatory program as
"Weatherspoon Ash Pond Dam" (State I.D. No. ROBES-009).
H&H Evaluation Criteria
The computer program HydroCAD was used to perform the H&H calculations to route the design
storm through the ash basin, to identify the hydraulic conditions within the basin for the proposed
decommissioned condition. The Weatherspoon Ash Basin, in the decommissioned conditions,
will consist of the basin dikes with an opening (breach) in the southern dike section. The dike
opening is designed to be approximately 100 feet wide, cut to an elevation of 120 feet.
The Weatherspoon Ash Basin design storm for the decommissioned condition is the 100-year
storm event, which equates to 9.08 inches of rainfall for a six (6) hour period.
H&H Summary
Using the information above and the design storm hydrograph, the design storm safely passes
the decommissioned condition for the basin. A summary of the H&H modeling is provided in
Table 1.

Duke Energy
October 11, 2019
Page 3
Conclusion
Weatherspoon Station
Hydrology and Hydraulics Analysis Summary Report
Wood Project No. 7812180072
Table 1 - H&H Results
Results for Decommissioned
Condition
Weatherspoon
Ash Basin
Peak Water Elevation (ft)
121.1
Weir (Opening) Elevation (ft)
120.0
Dike Crest Elevation (ft)
143.6
Pond Freeboard (ft)
22.5
Peak Discharge Rate (ft3/s)
258.71
Peak Velocity (ft/s)
2.33
Based on the results of this H&H analysis, Wood concludes that the decommissioned ash basin
with safely pass the design storm event without overtopping the remaining dike remnants.
Furthermore, the discharge velocity through the dike opening should not cause erosive conditions
across the weir section or adjacent dike slopes.
Closing
Wood appreciates the opportunity to offer our services on this project. If you have any
questions concerning this response, please contact us.
Sincerely,
Wood Environment & Infrastructure Solutions, Inc.
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Nick Parks, PE Jeffery A. Mann, PE
Project Engineer Project Manager
Attachments H&H Calculation — Decommissioned Conditions

DDAB
Ash Basin
BREACH
Breach t
hannel
OUTLET
Outlet
SubCat Reach on Link Routing Diagram for Weatherspoon CAMA Closure Breach
Prepared by AMECFW, Printed 9/23/2019
HydroCADO 10.00-25 s/n 01035 © 2019 HydroCAD Software Solutions LLC

Weatherspoon CAMA Closure Breach
Prepared by AMECFW Printed 9/23/2019
HydroCAD® 10.00-25 s/n 01035 ©2019 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(acres) (subcatchment-numbers)
60.000 86 Newly graded area, HSG B (DA-AB)
60.000 86 TOTAL AREA

Weatherspoon CAMA Closure Breach
Prepared by AMECFW Printed 9/23/2019
HydroCAD® 10.00-25 s/n 01035 ©2019 HydroCAD Software Solutions LLC Page 3
Soil Listing (all nodes)
Area Soil Subcatchment
(acres) Group Numbers
0.000
HSG A
60.000
HSG B DA-AB
0.000
HSG C
0.000
HSG D
0.000
Other
60.000
TOTAL AREA

Weatherspoon CAMA Closure Breach
Prepared by AMECFW Printed 9/23/2019
HydroCADO 10.00-25 s/n 01035 © 2019 HydroCAD Software Solutions LLC Page 4
Ground Covers (all nodes)
HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment
(acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers
0.000 60.000 0.000 0.000 0.000 60.000 Newly graded area DA-AB
0.000 60.000 0.000 0.000 0.000 60.000 TOTAL AREA

Weatherspoon CAMA Closure Breach Type 11 6-hr 24.00 hrs 100 Rainfall=9.08"
Prepared by AMECFW Printed 9/23/2019
HydroCAD® 10.00-25 s/n 01035 ©2019 HydroCAD Software Solutions LLC Page 5
Time span=0.00-160.00 hrs, dt=0.01 hrs, 16001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method
Subcatchment DA-AB: Ash Basin Runoff Area=60.000 ac 0.00% Impervious Runoff Depth=7.38"
Flow Length=1,682' Slope=0.0100'/' Tc=23.1 min CN=86 Runoff=258.87 cfs 36.909 of
Reach BREACH: Breach Channel Avg. Flow Depth=1.08' Max Vet=2.33 fps Inflow=258.87 cfs 36.909 of
n=0.069 L=180.0' S=0.0111 T Capacity=1,456.56 cfs Outflow=258.71 cfs 36.909 of
Link OUTLET: Outlet
Inflow=258.71 cfs 36.909 of
Primary=258.71 cfs 36.909 of
Total Runoff Area = 60.000 ac Runoff Volume = 36.909 of Average Runoff Depth = 7.38"
100.00% Pervious = 60.000 ac 0.00% Impervious = 0.000 ac

Weatherspoon CAMA Closure Breach Type 11 6-hr 24.00 hrs 100 Rainfall=9.08"
Prepared by AMECFW Printed 9/23/2019
HydroCADO 10.00-25 s/n 01035 © 2019 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment DA-AB: Ash Basin
Runoff = 258.87 cfs @ 11.88 hrs, Volume= 36.909 af, Depth= 7.38"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-160.00 hrs, dt= 0.01 hrs
Type II 6-hr 24.00 hrs 100 Rainfall=9.08"
Area (ac) CN Description
60.000 86 Newly graded area, HSG B
60.000 100.00% Pervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
12.1
100
0.0100
0.14
Sheet Flow,
Grass: Short n= 0.150 P2= 3.68"
8.3
500
0.0100
1.00
Shallow Concentrated Flow,
Nearly Bare & Untilled Kv= 10.0 fps
2.7
1,082
0.0100
6.75
54.04 Channel Flow,
Area= 8.0 sf Perim= 8.0' r= 1.00'
n= 0.022 Earth, clean & straight
23.1 1,682 Total
Subcatchment DA-AB: Ash Basin
Hydrograph
258.87 cfs
250 Type II
6-hr 24.00 hrs
-409 Rainfall=9.08"
200 Runoff Area=60.000 ac
Rurr off Voll.�me=36�09 of
150 Runoff Depth=7.38"
_o Flow LengthT1,682'
100 Slope=0.Q100 '/'
Tc=23.1 m i n
50 1 CN=86
0 20 40 60 80 11 1 41 61
0 Runoff

Weatherspoon CAMA Closure Breach Type 11 6-hr 24.00 hrs 100 Rainfall=9.08"
Prepared by AMECFW Printed 9/23/2019
HydroCAD® 10.00-25 s/n 01035 ©2019 HydroCAD Software Solutions LLC Page 7
Summary for Reach BREACH: Breach Channel
Inflow Area = 60.000 ac, 0.00% Impervious, Inflow Depth = 7.38" for 100 event
Inflow = 258.87 cfs @ 11.88 hrs, Volume= 36.909 of
Outflow = 258.71 cfs @ 11.88 hrs, Volume= 36.909 af, Atten= 0%, Lag= 0.1 min
Routing by Dyn-Stor-Ind method, Time Span= 0.00-160.00 hrs, dt= 0.01 hrs
Max. Velocity= 2.33 fps, Min. Travel Time= 1.3 min
Avg. Velocity = 0.65 fps, Avg. Travel Time= 4.6 min
Peak Storage= 19,987 cf @ 11.88 hrs
Average Depth at Peak Storage= 1.08'
Bank -Full Depth= 3.00' Flow Area= 327.0 sf, Capacity= 1,456.56 cfs
100.00' x 3.00' deep channel, n= 0.069 Riprap, 6-inch
Side Slope Z-value= 3.0 '/' Top Width= 118.00'
Length= 180.0' Slope= 0.0111 T
Inlet Invert= 116.00', Outlet Invert= 114.00'
f
Reach BREACH: Breach Channel
Hydrograph
Inflow .0 000 .
1 %% Avg. Flow -. 0:
Max Vel=2.33 fps
11 %% 0.•
:0
1 % FL
11
12222 ii
0 20 40 60 80 100 120 140 1I
❑ Inflow
❑ Outflow

Weatherspoon CAMA Closure Breach Type 11 6-hr 24.00 hrs 100 Rainfall=9.08"
Prepared by AMECFW Printed 9/23/2019
HydroCAD® 10.00-25 s/n 01035 ©2019 HydroCAD Software Solutions LLC Page 8
Summary for Link OUTLET: Outlet
Inflow Area = 60.000 ac, 0.00% Impervious, Inflow Depth = 7.38" for 100 event
Inflow = 258.71 cfs @ 11.88 hrs, Volume= 36.909 of
Primary = 258.71 cfs @ 11.88 hrs, Volume= 36.909 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-160.00 hrs, dt= 0.01 hrs
3
0
FZ
Link OUTLET: Outlet
Hydrograph
0 20 40 60 80 100 120 140 160
Time (hours)
❑ Inflow
❑ Primary