20171559 Ver 3_More Info Received - SW Managment Plan & DMS Acceptance_20211020

Homewood, Sue
From: Miller, Vickie M. (Raleigh) <[e-mail]>
Sent: Wednesday, October 20, 2021 11:43 PM
To: Wendee Smith; Gibby, Jean B CIV USARMY CESAW (USA); Homewood, Sue
Cc: Masemore, Sushma; Lane, Bill F; Nicholson, John A.; Smith, Danny; Wojoski, Paul A;
[e-mail]; Pruitt, Carl E Jr CIV USARMY CESAW (USA); Jim
Melvin; Anna Lea Moore; Brent Christensen; William Ross; V. Randall (Randy) Tinsley
Subject: [External] RE: GRMS 404/401 Permit Application - Follow-up
Attachments: Greensboro Randolph Megasite DMS Conditional Acceptance Oct21.pdf;
GRMS_Stormwater Management Plan_20211020.pdf
Follow Up Flag: Follow up
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Good evening,
Please find attached additional information pertaining to the Greensboro Randolph Megasite 404/401
permit application. The attachments include the updated DMS Acceptance Letter and the Stormwater
Management Plan.
Thank you,
Vickie
Vickie Miller, AICP, Pws
D 919.232.6637 M 919.559.2632
hdrinc.com/follow-us
From: Wendee Smith <[e-mail]>
Sent: Friday, October 15, 2021 10:06 PM
To: Gibby, Jean B CIV USARMY CESAW (USA) <[e-mail]>; Homewood, Sue
<[e-mail]>
Cc: Masemore, Sushma <[e-mail]>; [e-mail]; [e-mail]; Smith,
Danny <[e-mail]>; Wojoski, Paul A <[e-mail]>; [e-mail];
Pruitt, Carl E Jr CIV USARMY CESAW (USA) <[e-mail]>; Jim Melvin <[e-mail]>; Anna Lea
Moore <[e-mail]>; Brent Christensen <[e-mail]>; Miller, Vickie M. (Raleigh)
<[e-mail]>; William Ross <[e-mail]>; V. Randall (Randy) Tinsley
<[e-mail]>
Subject: GRMS 404/401 Permit Application - Follow-up
rCAUI ION: [EXTERNAL] This email originated from outside of the organization. Do not click links or open attachments
less you recognize the sender and know the content is safe.
Hello,
i

Please find attached additional information pertaining to the Greensboro Randolph Megasite 404/401
permit application. Attachments include a transmittal letter detailing all items included in this
submittal.
We appreciate and look forward to your review.
Respectfully,
Wendee
Wendee B. Smith, Owner
[e-mail]
919.270.8430
le 52 Consulting
2

ROY COOPER
Governor
ELIZABETH S. BISER
Secrerary
NORTH CAROLINA
Environmental Quality
October 19, 2021
Jim Melvin
Greensboro Randolph Megasite Foundation
324 W. Wendover Ave., Suite 207
Greensboro, NC 27408
Expiration of Acceptance: 4/19/2022
Project: Greensboro Randolph Megasite County: Randolph
This is a conditional acceptance letter.
The purpose of this letter is to notify you that the NCDEO Division of Mitigation Services (DMS) is willing to
accept payment for compensatory mitigation for impacts associated with the above referenced project as
indicated in the table below. Please note that this decision does not assure that participation in the DMS in -
lieu fee mitigation program will be approved by the permit issuing agencies as mitigation for project impacts.
It is the responsibility of the applicant to contact permitting agencies to determine if payment to the DMS will
be approved. You must also comply with all other state. federal or local government permits, regulations or
authorizations associated with the proposed activity including G.S. § 143-214.11.
This acceptance is valid for six months from the date of this letter and is not transferable. If we have not
received a copy of the issued 404 Permitl401 Certification within this time frame, this acceptance will
expire. It is the applicant's responsibility to send copies of the permits to DMS. Once DMS receives a copy
of the permit(s) an invoice will be issued based on the required mitigation in that permit and payment must
be made prior to conducting the authorized work. The amount of the in -lieu fee to be paid by an applicant is
calculated based upon the Fee Schedule and policies listed on the DMS website.
Based on the information supplied by you in your request to use the DMS, the impacts for which you are
requesting compensatory mitigation credit are summarized in the following table. The amount of mitigation
required and assigned to DMS for this impact is determined by permitting agencies and may exceed the
impact amounts shown below.
River Basin
Impact Location
(8-digit HUC)
Impact Type
Impact Quantity
Cape Fear
03030003*
Warm Stream
42.639
Cape Fear
03030003'
Riparian Wetland
9.75
*DMS proposes to provide the required mitigation credits for the above -referenced impacts in the Cape Fear
03030002 and 03030003 HUCs. Upon receipt of payment. DMS will take responsibility for providing the
compensatory mitigation. The mitigation will be performed in accordance with the In -Lieu Fee Program
instrument dated July 28, 2010. Thank you for your interest in the DMS in -lieu fee mitigation program. If you
have any questions or need additional information, please contact [e-mail].
cc: Vickie Miller, agent
GDE
:ewm,— o� _*.man—r��ai :_ai�
Sincerely.
FOR James. 6 Stanfill
Asset Management Supervisor
North Carolina Department of Environmental Quality I Division of Mitigation Services
217 West Jones Street 11652 Mail Service Center I Raleigh. North Carolina 27699-1652
919.707.8976

FN
STORMWATER
MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Randolph County, North Carolina
October 20, 2021

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STORMWATER
MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
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October 20, 2021
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10

STORMWATER PLAN
MENT
GREENNSBORO-RA DO PHEMEAGASITE I
Table of Contents
1 Introduction 1
2 Site Description 1
3 Project Description 1
4 Stormwater Management Plan 1
4.1 Design Requirements 2
4.2 Existing Conditions Model 2
4.2.1 Outfall Locations and Drainage Areas 2
4.2.2 Runoff Curve Numbers and Time of Concentration 3
4.2.3 Rainfall 3
4.2.4 Existing Peak Discharges 3
4.3 Proposed Stormwater Control Measures 4
4.3.1 Pond Al — Dry Detention Basin 4
4.3.2 Pond A2 — Dry Detention Basin 4
4.3.3 Pond A3 — Wet Pond 4
4.3.4 Pond B1 — Dry Detention Basin 5
4.3.5 Pond B2 — Wet Pond 5
4.3.6 Pond Cl — Dry Detention Basin 5
4.3.7 Pond C2 — Wet Pond 5
4.4 Proposed Conditions Model 6
4.4.1 Proposed Pond Locations and Drainage Areas 6
4.4.2 Runoff Curve Numbers and Time of Concentration 6
4.4.3 Rainfall 7
4.4.4 Proposed Peak Discharges 7
4.4.5 Conclusion 7
5 References 8
Tables
Table 1. Summary of RCN and Tc 3
Table 2. 24-hour Total Rainfall 3
Table 3. Existing Peak Discharges 4
Table 4. Summary of Proposed RCN and Tc 6
Table 5. Proposed Peak Discharges 7
Appendices
Appendix A — Figures
Appendix B - NOAA Atlas 14 Rainfall Depths
Appendix C — Existing Condition Model Results
Appendix D — Proposed Ponds
Appendix E — Proposed Conditions Model Results
October 20, 2021 I i

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
1 Introduction
The Greensboro -Randolph Megasite (GRMS) is a large tract of land located in Randolph
County, North Carolina that can support large-scale manufacturing facilities. Currently,
there are plans to construct approximately 1000 acres of manufacturing and distribution
facilities. The purpose of this document is to summarize how the stormwater will be
managed to meet the State of North Carolina requirements as well as provide additional
controls to manage the larger flood events to reduce risk of increased downstream
flooding.
2 Site Description
The roughly 1,800-acre site is in the northeast portion of Randolph County between US
421 and Old 421 Road near the county line as shown on Figure 1 in Appendix A. Old
421 Road bounds the northern property boundary and is also the natural ridge, so all of
the property drains in southerly direction towards Dodson Lake and Sandy Creek.
Dodson Lake stream and Dodson Lake is located along the southern boundary of the
site and confluences with Sandy Creek just southeast of the property. There are two (2)
main tributaries on the site that drain into Dodson Lake and one (1) main tributary on the
site that drains into Sandy Creek. Dodson Lake stream and portions of Dodson Lake
Tributary 1 and Sandy Creek Tributary 7 have limited detailed studied (LDS) special
flood hazard areas (SFHAs)
The site consists mainly of farm and pasture lands with some forested areas in the
southern and eastern portion of the site. There are several small farm ponds within the
project area.
3 Project Description
The overall project is the construction of a manufacturing facility that covers
approximately 1,000 acres. The facility includes multiple office, manufacturing, and
storage buildings along with employee parking, truck access, rail yard, and other
ancillary facilities that support the manufacturing process. The manufacturing facility
requires large level areas for efficient processes and therefore the site will require areas
of cut and fill to create the level building areas. A significant portion of the site will be
impervious surfaces and the remaining areas will likely be grass and landscaped areas.
Stormwater Management Plan
The overall stormwater management plan for the GRMS includes a combination of dry
attenuation basins located on the level pads and water quality ponds located near the toe
of the pads to control stormwater runoff and comply with the North Carolina post
construction stormwater requirements. The built upon site area will drain to the dry
October 20, 2021 11

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
attenuation basins which will reduce the peak discharges to existing levels and the water
quality ponds will provide treatment of the stormwater runoff from the built upon area
prior to the identified outfalls which are just upstream of Dodson Lake and where Sandy
Creek Tributary 7 leaves the site.
This section summarizes the stormwater management requirements, describes how the
existing peak discharges were determined at the identified outfall locations, presents
each of the proposed dry attenuation basins and water quality ponds and summarizes
the results of the hydrologic and hydraulic model.
4.1 Design Requirements
The State of North Carolina Department of Environmental Quality (NCDEQ) Division of
Energy, Mineral, and Land Resources (DEMLR) Stormwater Program oversees
compliance of the stormwater runoff regulations. The regulations vary across the state
depending on the watershed. The GRMS is located within a Watershed III Basin and is a
high -density project requiring compliance with the post construction stormwater
regulations that meet 15A NCAC 02H .1020 Universal Stormwater Management
Program which includes:
• Runoff treatment of the built upon area through a primary stormwater control
measure (SCM) as identified in the NCDEQ Stormwater Design Manual.
o The wet pond is a primary SCM.
• Demonstration that the 10-year peak discharge from the site will not increase
downstream erosion.
o By attenuating the proposed 10-year peak discharge to the existing
condition level, the stormwater outlets will not cause erosion downslope
of the discharge point over current levels.
In addition to the NCDEQ post construction regulations, the GRMS SCMs were also
designed to not increase the existing 100-year peak discharge. This additional
attenuation is being performed to reduce the risk of increased downstream flooding and
supports the removal of existing SFHA areas on the project site.
4.2 Existing Conditions Model
The existing peak discharges were developed using the HydroCAD computer model
which generates stormwater hydrographs for defined areas and routes and combines
these hydrographs at specified locations. For this project the stormwater hydrographs
were generated using the National Resource Conservation Service (NRCS) runoff curve
number method (RCN) method along with the NOAA Atlas 14 center weighted storm
distribution for the different storm frequency events.
4 2.1 Outfall Locations and Drainage Areas
Three (3) outfalls were identified and referred to as A, B and C. Outfall A and B are
located just upstream of Dodson Lake and outfall C is located on Sandy Creek Tributary
7 just upstream of where the tributary leaves the project site. These outfall locations are
shown on Figure 1 in Appendix A.
2 I October 20, 2021

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
4.2.2 Runoff Curve Numbers and Time of Concentration
A weighted RCN was determined for each drainage area based on the landuse and soil
type. The landuse and soils are shown in Figures 2 and 3 in Appendix A.
The time of concentration (Tc) represent the longest travel time of stormwater runoff in a
drainage area. The NRCS Tc method identifies three (3) different travel paths, sheet
flow, shallow concentrated, and channel flow. The travel time for each of these paths are
summed up to determine the Tc. A summary of the RCN and Tc for each of the drainage
areas are shown in Table 1 below.
Table 1. Summary of RCN and Tc
Drainage Area
Area (Ac)
RCN
Tc (min)
Al
235
78
63
B1
520
77
83
Cl
740 77
103
4.2.3 Rainfall
The point frequency rainfall data was obtained from NOAA Atlas 14 for the 1-, 10-, 25-,
50-, and 100-year annual frequency events. For the stormwater management plan the
24-hour duration event was used to demonstrate compliance. A summary of the total
rainfall amounts is shown in Table 2 below and a copy of the NOAA Atlas 14 is provided
in Appendix B.
Table 2. 24-hour Total Rainfall
Annual Frequency
Depth (in)
1-Year
2.89
10-Year
5.04
25-Year
5.95
50-Year 6.68
100-Year 7.42
The NRCS Curve B was used to distribute the rainfall across the 24-hour period. This
distribution is based on the NOAA Atlas 14 recommended center weighted storm and
introduces a smoothing factor depending on the location. The GRMS is in the curve B
region.
4.2.4 Existing Peak Discharges
The results of the existing conditions HydroCAD model are shown in Table 3 below. The
HydroCAD model results are provided in Appendix C.
October 20, 2021 13

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Table 3. Existing Peak Discharges
Duffel! Point
10-yr Peak
Discharge (cfs)
100-yr Peak
Discharge (cfs)
A
345
610
550
985
680
1220
4.3 Proposed Stormwater Control Measures
The proposed SCMs include four (4) dry detention basins located within the site pads
and three (3) wet ponds located just south of the fill slope and upstream of the outfall
locations.
The built upon area all drains to the dry detention basins through a combination of onsite
storm drainage system and swales. The SCMs in outfall drainage area A and B were
designed for all the area naturally draining to the facilities. The offsite area in outfall C
will be diverted around the SCMs. Below is a brief description of the proposed SCMs
and an overview is shown in Figure 4 in Appendix A. Grading of the proposed SCMs are
shown in Appendix D.
4.3.1 Pond Al — Dry Detention Basin
Pond Al is a dry detention basin that will have a ponded surface area of approximately
3.4 acres and a maximum depth of 8.8 feet during 100-year rainfall event. The outlet
structure is a 6 feet x 6 feet riser structure with a 24-inch diameter orifice at the bottom of
the riser. The riser is 6 feet tall and discharges to a 60-inch outlet barrel that will
discharge near the toe of the pad fill.
The pond captures 99.3 acres of the site.
4.3.2 Pond A2 — Dry Detention Basin
Pond A2 is a dry detention basing that will have a ponded surface area of approximately
4.6 acres and a maximum depth of 10.5 feet during the 100-year rainfall event. The
outlet structure is a 10 feet x 10 feet riser structure with a 24-inch orifice at the bottom of
the basin. The riser is 8 feet tall and discharges to a 60-inch outlet barrel that will
discharge near the toe of the pad fill.
The pond captures 125 acres of the site.
4.3.3 Pond A3 — Wet Pond
Pond A3 is wet pond designed to satisfy the surface area requirements based on the
built upon area percent imperviousness and the surface area to drainage area ratio for a
six (6) feet deep normal pool. The riser structure was sized to temporarily store the
water quality volume and release this volume over a 4-5-day period.
4 I October 20, 2021

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Pond A3 will provide WQ volume for 278.5 acres of the site and will have a permeant
pool surface area of approximately 3.2 acres. The normal pool depth is 6 feet while the
peak depth for the 100-year storm is 13.7 feet.
This pond is controlled by 10 feet x 10 feet riser with a 7-inch orifice at the normal pool
elevation. The top of the riser and top of dam are 9 feet and 15 feet above the pond
bottom respectively. The orifice and riser discharge to a 72-inch outlet barrel that will
discharge just upstream of the outfall point A.
4.3.4 Pond B1 — Dry Detention Basin
Pond B1 is a dry detention basing that will have a ponded surface area of approximately
10.2 acres and a maximum depth of 15.0 feet during the 100-year rainfall event. The
outlet structure is a 10 feet x 10 feet riser structure with a 24 in orifice at the bottom of
the riser. The riser is 10 feet tall and discharges to a 60-inch outlet barrel that will
discharge near the toe of the pad fill.
The pond captures 279 acres of the site.
4.3.5 Pond B2 — Wet Pond
Pond B2 is wet pond designed to satisfy the surface area requirements based on the
built upon area percent imperviousness and the surface area to drainage area ratio for a
five (5) feet deep normal pool. The riser structure was sized to temporarily store the
water quality volume and release this volume over a 4-5-day period.
Pond B2 will provide WQ volume for 304.8 acres of the site and will have a permanent
pool surface area of approximately 4.9 acres. The normal pool depth is 6 feet while the
peak depth for the 100-year storm is 12.0 feet.
This pond is controlled by a 10 feet x 10 feet riser with an 8-inch orifice at the normal
pool elevation. The top of the riser and top of dam are 9 feet and 14 feet above the pond
bottom respectively. The orifice and riser discharge to a 66-inch outlet barrel that will
discharge just upstream of the outfall point B
4.3.6 Pond C1 — Dry Detention Basin
Pond C1 is a dry detention basing that will have a ponded surface area of approximately
14.8 acres and a maximum depth of 16.6 feet during the 100-year rainfall event. The
outlet structure is a 15 feet x 15 feet riser structure with a 24-inch orifice at the bottom of
the riser. The riser is 10 feet tall and discharges to a 72-inch outlet barrel that will
discharge near the toe of the pad fill.
The pond captures 534 acres of the site
.3.7 Pond C2 — Wet Pond
Pond C2 is wet pond designed to satisfy the surface area requirements based on the
built upon area percent imperviousness and the surface area to drainage area ratio for a
six (6) feet deep normal pool. The riser structure was sized to temporarily store the
water quality volume and release this volume over a 4-5-day period.
October 20, 2021 15

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Pond C2 will provide WQ volume for 533.8 acres of the site and will have a permeant
pool surface area of approximately 8.9 acres. The normal pool depth is 6 feet while the
peak depth for the 100-year storm is 11.4 feet.
This pond is controlled by a 10 feet x 10 feet riser with a 10-inch orifice at the normal
pool elevation. The top of the riser and top of dam are 9 feet and 13.5 feet above the
pond bottom respectively. The orifice and riser discharge to a 72-inch outlet barrel that
will discharge just upstream of the outfall point C.
4.4 Proposed Conditions Model
The drainage areas for each outfall were modified to reflect the proposed conditions in
the HydroCAD model and the SCMs were added to the model. Areas that don't drain to
the SCMs were added to each outfall to determine the proposed condition peak
discharges at each outfall point. The RCN and Tc's were recalculated for each drainage
area based on the proposed built out conditions.
4.4.1 Proposed Pond Locations and Drainage Areas
The three (3) outfalls used for the existing conditions model were preserved, but the
drainage conditions between these outfalls was modified to account for the proposed site
design. These ponds and drainage areas are shown in Figure 4 in Appendix A.
4.4.2 Runoff Curve Numbers and Time of Concentration
A weighted RCN was determined for each drainage area based on the landuse and soil
type. Areas that were affected by the proposed site plan were assumed to be either
graded grass on D type soils, or impervious area while areas that were not affected were
calculated based on the existing landuse and soils and remained unchanged.
The time of concentration (Tc) represent the longest travel time of stormwater runoff in a
drainage area. The NRCS Tc method identifies three (3) different travel paths, sheet
flow, shallow concentrated, and channel flow. The travel time for each of these paths are
summed up to determine the Tc. A summary of the RCN and Tc for each of the drainage
areas are shown in Table 4 below.
Table 4. Summary of Proposed RCN and Tc
Drainage Area
Area (Ac)
RCN
Tc (min)
Al
99
94
20
A2
125
95
A3.0
56
76
30
pp,4. U 37
78 . 22
B1 279 95 30
B2.0 26 74 .30
B3.0 70 74 30
6 I October 20, 2021

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Table 4. Summary of Proposed RCN and Tc
Drainage Area
Area (Ac)
RCN
Tc (min)
C1
254
91
30
C2.0
345
74
60
4.4.3 Rainfall
The proposed condition rainfall conditions were identical to the existing conditions model
to provide comparability. This storm is the 100-year depths distributed throughout 24-
hours using NRCS Curve B.
4.4.4 Proposed Peak Discharges
The results of the proposed conditions HydroCAD model are shown in Table 5 below.
Table 5. Proposed Peak Discharges
Duffel! Point
10-yr Peak
Discharge (cfs)
100-yr Peak
Discharge (cfs)
A
340
515
265
380
405
755
These results show that the peak discharge for all three outfalls were reduced compared
to the existing conditions presented in Table 3. The HydroCAD model results are
presented in Appendix E.
4.4.5 Conclusion
This stormwater management plan demonstrates that the built upon area as well as
some of the areas outside of the built upon area drain through a dry detention basin that
reduces the peak discharges to at or below the existing conditions peak discharges at
the three (3) identified outfall locations. The reduction in the 10-year peak discharge to
below the existing condition peak discharge will prevent an increase in erosion
downstream of the property. The reduction in the 100-year peak discharge to below
existing condition peak discharge will reduce the risk of downstream flooding during the
100-year event and support the removal of some SFHAs on the project site. All of the
outflow from the dry detention basins will be discharged to wet ponds that are sized per
the NCDEQ Stormwater Manual to provide the required water quality treatment prior to
being discharge off the site.
October 20, 2021 1 7

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
5 References
HydroCAD version 10.00-25
2019, HydroCAD Software Solutions LLC
Stormwater Design Manual
January 1, 2017, updated on November 20, 2020 — North Carolina Division of Environmental
Quality, Department of Energy, Mineral, and Land Resources
Urban Hydrology for Small Watersheds — TR-55
June 1986 — United States Department of Agriculture, Natural Resource Conservation Service
NOAA Atlas 14 Precipitation -Frequency Atlas of the United States — Volume 2
2006 — National Oceanic and Atmospheric Administration
8 I October 20, 2021

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Appendix A - Figures
October 20, 2021 11

LEGEND
Existing Flowpaths
Existing Drainage Areas
Site Boundary
Q Outfall Points
r
0
F�2
EXISTING DRAINAGE CONDITIONS
GREENSBORO MEGASITE
FIGURE 1
PATH: A:\GIS\PROJECTSY10000000_GRMS_UPDATE\7.2_VNP\MAP_DOCS\APRX\EXHIBITS.APRX - USER: LVANDERLIN - DATE: 10/15/2021
INITIAL STORMWATER MANAGEMENT PLAN

s
LEGEND
NLCD Landuse
▪ Open Water
Developed, Open Space
Developed, Low Intensity
▪ Developed, Medium Intensity Pasture/Hay
▪ Developed, High Intensity - Cutivated Crops
iBarren Land Woody Wetlands
▪ Deciduous Forest Emergent Herbaceous Wetlands
•
• r
F�2
.171411 w-
M�
r
i
•
•
ii".71:811
it
f bowl
1.40
r
at
EXISTING LANDUSE
GREENSBORO MEGASITE
FIGURE 2
PATH: A:\GIS\PROJECTS,00000000_GRMS_UPDATE\7.2_VNP\MAP_DOCS\APRX\EXHIBITS.APRX - USER: LVANDERLIN - DATE: 10/15/2021
INITIAL STORMWATER MANAGEMENT PLAN

O Outfall Points
Proposed Drainage Areas
Proposed Ponds
Site Boundary
0
0.6 A
F�2
PROPOSED DRAINAGE CONDITIONS
GREENSBORO MEGASITE
FIGURE 4
PATH: A:\GIS\PROJECTS \00000000_GRMS_UPDATE/7.2_VNP\MAP_DOCS\APRX\EXHIBITS.APRX - USER: LVANDERLIN - DATE: 10/19/2021
INITIAL STORMWATER MANAGEMENT PLAN

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Appendix B — NOAA Atlas 14 Rainfall Depths
2 I October 20, 2021

10/19/21, 12:06 PM Precipitation Frequency Data Server
NOAA Atlas 14, Volume 2, Version 3
Location name: Whitsett, North Carolina, USA*
Latitude: 36.0596°, Longitude: -79.5835°
Elevation: 628.26 ft**
*source: ESRI Maps
"'source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley
NOAA, National Weather Service, Silver Spring, Maryland
PF tabular 1 PF graphical 1 Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Duration
Average recurrence interval (years)
1
2
5
10
25
50 100 200 500 1000
5-min
0.388
0.461
0.536
0.586
0.641
0.674
0.704
0.727
0.750
0.764
(0.355-0.423)
(0.422-0.503)
(0.491-0.585)
(0.536-0.639)
(0.583-0.697)
(0.611-0.734)
(0.635-0.767)
(0.653-0.793)
(0.667-0.818)
(0.674-0.834)
10-min
0.619
0.737
0.858
0.937
1.02
1.07
1.12
1.15
1.19
1.20
(0.566-0.675)
(0.675-0.804)
(0.786-0.937)
(0.857-1.02)
(0.928-1.11)
(0.973-1.17)
(1.01-1.22)
(1.03-1.26)
(1.06-1.29)
(1.06-1.31)
15-min
0.774
0.926
1.09
1.19
1.29
1.36
1.41
1.46
1.49
1.51
(0.708-0.844)
(0.849-1.01)
(0.994-1.19)
(1.08-1.29)
(1.18-1.41)
(1.23-1.48)
(1.28-1.54)
(1.31-1.59)
(1.33-1.63)
(1.33-1.65)
30-min
1.06
1.28
1.54
1.72
1.92
2.05
2.17
2.26
2.38
2.44
(0.970-1.16)
(1.17-1.40)
(1.41-1.69)
(1.57-1.87)
(1.74-2.09)
(1.86-2.23)
(1.95-2.36)
(2.03-2.47)
(2.12-2.59)
(2.16-2.67)
60-min
1.32
1.61
1.98
2.24
2.55
2.78
2.98
3.18
3.41
3.57
(1.21-1.44)
(1.47-1.75)
(1.81-2.16)
(2.05-2.44)
(2.32-2.78)
(2.52-3.02)
(2.69-3.25)
(2.85-3.47)
(3.03-3.72)
(3.15-3.90)
2-hr
1.56
1.89
2.35
2.68
3.10
3.42
3.72
4.01
4.39
4.66
(1.43-1.70)
(1.74-2.07)
(2.15-2.56)
(2.45-2.92)
(2.82-3.38)
(3.09-3.71)
(3.34-4.04)
(3.58-4.36)
(3.87-4.76)
(4.07-5.06)
3-hr
1.67
2.03
2.52
2.89
3.35
3.69
4.03
4.36
4.79
5.10
(1.54-1.82)
(1.87-2.21)
(2.32-2.74)
(2.65-3.13)
(3.05-3.62)
(3.35-3.99)
(3.63-4.36)
(3.90-4.71)
(4.23-5.17)
(4.46-5.52)
6-hr
2.03
2.46
3.05
3.51
4.11
4.58
5.05
5.53
6.16
6.65
(1.88-2.22)
(2.27-2.68)
(2.81-3.33)
(3.22-3.81)
(3.74-4.45)
(4.14-4.96)
(4.53-5.46)
(4.90-5.97)
(5.38-6.66)
(5.73-7.19)
12-hr
2.42
2.92
3.66
4.23
5.02
5.65
6.31
6.98
7.93
8.67
(2.23-2.64)
(2.70-3.20)
(3.36-3.99)
(3.87-4.61)
(4.56-5.44)
(5.09-6.11)
(5.62-6.80)
(6.15-7.52)
(6.85-8.54)
(7.37-9.34)
24-hr
2.84
3.43
4.28
4.95
5.85
6.57
7.31
8.07
9.12
9.94
(2.64-3.06)
(3.19-3.70)
(3.98-4.61)
(4.59-5.32)
(5.40-6.31)
(6.05-7.08)
(6.70-7.89)
(7.37-8.73)
(8.27-9.89)
(8.97-10.8)
3.32
3.99
4.94
5.66
6.64
7.40
8.18
8.97
10.0
10.9
2-clay
(3.10-3.56)
(3.73-4.29)
(4.61-5.30)
(5.27-6.08)
(6.16-7.13)
(6.84-7.97)
(7.53-8.82)
(8.22-9.70)
(9.16-10.9)
(9.88-11.8)
3.51
4.21
5.20
5.96
6.99
7.80
8.62
9.47
10.6
11.5
3-clay
(3.28-3.76)
(3.94-4.53)
(4.86-5.58)
(5.56-6.40)
(6.49-7.51)
(7.21-8.39)
(7.94-9.29)
(8.69-10.2)
(9.68-11.5)
(10.4-12.5)
3.70
4.44
5.46
6.26
7.34
8.20
9.07
9.97
11.2
12.1
4-clay
(3.46-3.97)
(4.15-4.76)
(5.10-5.85)
(5.84-6.71)
(6.82-7.88)
(7.58-8.81)
(8.36-9.77)
(9.15-10.8)
(10.2-12.1)
(11.0-13.2)
4.24
5.06
6.14
7.00
8.16
9.09
10.0
11.0
12.3
13.3
7-clay
(3.98-4.53)
(4.75-5.40)
(5.76-6.56)
(6.55-7.47)
(7.62-8.72)
(8.45-9.73)
(9.28-10.8)
(10.1-11.8)
(11.3-13.3)
(12.2-14.5)
10-day
4.80
5.71
6.87
7.77
9.00
9.97
11.0
12.0
13.3
14.4
(4.52-5.13)
(5.37-6.09)
(6.45-7.32)
(7.28-8.29)
(8.40-9.61)
(9.27-10.7)
(10.2-11.7)
(11.0-12.8)
(12.2-14.4)
(13.1-15.6)
20-day
6.44
(6.08-6.83)
7.60
(7.17-8.07)
8.99
(8.48-9.54)
10.1
(9.51-10.7)
11.6
(10.9-12.3)
12.8
(12.0-13.6)
14.0
(13.1-15.0)
15.3
(14.1-16.3)
16.9
(15.6-18.2)
18.2
(16.7-19.7)
30-day
7.98
9.38
10.9
12.1
13.6
14.8
16.0
17.2
18.8
20.0
(7.59-8.41)
(8.91-9.88)
(10.3-11.5)
(11.5-12.7)
(12.9-14.4)
(14.0-15.7)
(15.1-16.9)
(16.1-18.2)
(17.5-20.0)
(18.5-21.3)
45-day
10.1
11.8
13.5
14.9
16.6
18.0
19.3
20.6
22.4
23.7
(9.59-10.6)
(11.2-12.4)
(12.9-14.2)
(14.1-15.6)
(15.8-17.5)
(17.0-19.0)
(18.2-20.4)
(19.4-21.8)
(20.9-23.7)
(22.1-25.2)
60-day
12.1
(11.6-12.7)
14.1
(13.5-14.8)
15.9
(15.2-16.7)
17.3
(16.5-18.2)
19.1
(18.2-20.1)
20.5
(19.5-21.5)
21.8
(20.6-22.9)
23.0
(21.8-24.3)
24.6
(23.2-26.0)
25.8
(24.3-27.3)
1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a
given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not
checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical
https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.0596&Ion=-79.5835&data=depth&units=english&series=pds 1/4

10/19/21, 12:06 PM
Precipitation Frequency Data Server
Precipitation depth (in)
Precipitation depth On:,
30
25
20
15
10
PDS-based dep_h-duration-frequency (DDF) curves
Latitude: 36.0596°, Longitude:-79.5835"
1 2 5 10
NOAA Atlas 14, Volume 2, Version 3
Duration
25
r r ra
r rq
1;11
N +V
b �
Y'V rY1 4r--
ri N rrl V in
50 100
Average recurrence interval (years)
200
I CI N
500 1000
Created {GMT}- Tie Oct 19 16-06:20 2021
Back to Top
Maps & aerials
Small scale terrain
Average recurrence
n1erva I
{years}
1
2
5
10
25
50
100
200
500
1000
❑u canon
- 5--rnFn — 2-clay
— 10-min — 3-stay
15-min — 4-day
— 30-min — 7-gay
— 8D-rnio — 10-day
— 2-hr — 20-day
— 3-hr — 30-day
— 6-hr — 46-day
— 12-r — 60-day
24-,hr
https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.0596&Ion=-79.5835&data=depth&units=english&series=pds 2/4

10/19/21, 12:06 PM Precipitation Frequency Data Server
Large scale terrain
Lynchburg
6lacksburg Roanoke
e1
Winston-Salem
Durham
Greensborf •
NORTH CAROLINA
100km
610mi
Fayetteville •
Large scale map
100km
610mi
North
Car 6I1 na
Large scale aerial
Raleigh
•
Darharr.
Raleig h
F. etteville
Rocky i
•
..r
Rocky I
6
•
+
0
https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=36.0596&Ion=-79.5835&data=depth&units=english&series=pds 3/4

10/19/21, 12:06 PM Precipitation Frequency Data Server
~alaekshurg 'ino e
r •
Zvi n st on-5'a l em
Greensbor0
Charlotte
100km
610mi 1
Durham*
hl c+rt n
tivarG•kns
. Raleigh
*
Fayetteville
Rocky r
•
Back to Top
US Department of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
National Water Center
1325 East West Highway
Silver Spring, MD 20910
Questions?: [e-mail]
Disclaimer
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STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Appendix C — Existing Condition Model
Results
October 20, 2021 13

(Al) (2) <Bi>
DA A1\ DA A2
<Subca>
A
Total DA A
Reach
DA 1
B
Total DA B
Total DA C
Routing Diagram for ExistingConditions
Prepared by HDR, Inc, Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC

ExistingConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Area Listing (all nodes)
Area CN Description
(acres) (subcatchment-numbers)
286.100 78 (A1, A2)
1,259.600 77 (B1, C1)
1,545.700 77 TOTAL AREA
Printed 10/20/2021
Page 2

ExistingConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Soil Listing (all nodes)
Area Soil Subcatchment
(acres) Group Numbers
0.000 HSG A
0.000 HSG B
0.000 HSG C
0.000 HSG D
1,545.700 Other Al, A2, B1, Cl
1,545.700 TOTAL AREA
Printed 10/20/2021
Page 3

ExistingConditions
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 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 0.000 0.000 0.000 1,545.700 1,545.700
0.000 0.000 0.000 0.000 1,545.700 1,545.700 TOTAL AREA
Al, A2, B1, C1

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 5
Time span=0.00-150.00 hrs, dt=0.05 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment Al: DA Al
Subcatchment A2: DA A2
Subcatchment B1: DA B1
Subcatchment Cl: DA Cl
Link A: Total DA A
Link B: Total DA B
Link C: Total DA C
Runoff Area=235.100 ac 0.00% Impervious Runoff Depth=4.86"
Tc=63.3 min CN=78 Runoff=544.52 cfs 95.167 af
Runoff Area=51.000 ac 0.00% Impervious Runoff Depth=4.86"
Tc=22.0 min CN=78 Runoff=212.86 cfs 20.644 af
Runoff Area=520.100 ac 0.00% Impervious Runoff Depth=4.75"
Tc=83.4 min CN=77 Runoff=984.09 cfs 205.662 af
Runoff Area=739.500 ac 0.00% Impervious Runoff Depth=4.75"
Tc=102.9 min CN=77 Runoff=1,219.94 cfs 292.418 af
Inflow=609.70 cfs 115.811 af
Primary=609.70 cfs 115.811 af
Inflow=984.09 cfs 205.662 af
Primary=984.09 cfs 205.662 af
Inflow=1,219.94 cfs 292.418 af
Primary=1,219.94 cfs 292.418 af
Total Runoff Area = 1,545.700 ac Runoff Volume = 613.891 af Average Runoff Depth = 4.77"
100.00% Pervious = 1,545.700 ac 0.00% Impervious = 0.000 ac

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment Al: DA Al
Runoff = 544.52 cfs @ 12.85 hrs, Volume=
95.167 af, Depth= 4.86"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Area (ac) CN Description
* 235.100 78
235.100 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
63.3
600
550�
500-
450
400i/
350-
300i/
250i/
200-
150-
100-
50-
Direct Entry,
Subcatchment Al: DA Al
Hyd rog raph
544.52 cf
NRCC 24-hr B
NRCC-100yr-24-hr Rainfall=742"
Iunof Area=25.100 ac
Runoff°Voi-ume=95.167 of
.......Ru.n.off...D.epth =486"
Tc=63.3 min
CN=78
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment A2: DA A2
Runoff = 212.86 cfs @ 12.32 hrs, Volume=
20.644 af, Depth= 4.86"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Area (ac) CN Description
51.000 78
51.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.0
230J
220
210:
200
190:
180:
170
160
150"
140:
130.
120
0 110v
LL 100
90"
80
70
50
50"
40
30:
20:
10
Direct Entry,
Subcatchment A2: DA A2
Hyd rog raph
11.R.C.....24-hr...B......
'NRCC-10Oyr-24-hr Rai 4.2"
Runoff _Area=51040 ac
R inoff':VoIu e=20.644::::af::::::
Runof€ Depth=486"
EN.=78.......
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment B1: DA B1
Runoff = 984.09 cfs @ 13.11 hrs, Volume=
205.662 af, Depth= 4.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Area (ac) CN Description
* 520.100 77
520.100 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
83.4 Direct Entry,
1,100J
1,050�
1,4
000:
950
900
850
800
750
700
650
600V
550y
0 500:
LL 450:
4004!
3504
3004!
250:
200:
1504
1004
50
Subcatchment B1: DA B1
Hyd rog raph
984.09 cf
1VRCG 24=For B
NR.CC.-10.0y.r. 2.4-hr Rainfall=7.42"
Runoff Area=520:.1.01)....a.c......
........R.unt.off...VVol.ume=205.662 af..
Runoff Depth=475"
Tc=03.4 min
10 20 30 40 50 60 70 80 90
Time (hours)
100
110
120 130
140 150
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment Cl: DA C1
Runoff = 1,219.94 cfs @ 13.37 hrs, Volume=
292.418 af, Depth= 4.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Area (ac) CN Description
* 739.500 77
739.500 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
102.9 Direct Entry,
1,300i/
1,200±Z
1,100-/
1,000V
9001/
8oa±-/
700-
600±-/
500 V
4001/
300-
200-
100
Subcatchment Cl: DA C1
Hyd rog raph
f 1,219.94 cf
NRCC 24-6r B
NRCC-100yr-24-hr Rainfall=7.42"
Runoff Area=739.50D ac
Rurroff Volume=292.418 af
Runoff Depth=4.75"
Tc=1.A2_.9....n.i.n......
CN=77
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 10
Summary for Link A: Total DA A
Inflow Area = 286.100 ac, 0.00% Impervious, Inflow Depth = 4.86" for NRCC-100yr-24-hr event
Inflow = 609.70 cfs @ 12.77 hrs, Volume= 115.811 af
Primary = 609.70 cfs @ 12.77 hrs, Volume= 115.811 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
0
Link A: Total DA A
Hydrograph
/.
.1.
1 609.70 cfs 1
650
09.70 cfs
600
550
500
450/
400 _
350
300
250
200
150
100
50 _
4.
1..
Inflow Area=286.100 ac
A./
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
[ Inflow
0 Primary

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 11
Summary for Link B: Total DA B
Inflow Area = 520.100 ac, 0.00% Impervious, Inflow Depth = 4.75" for NRCC-100yr-24-hr event
Inflow = 984.09 cfs @ 13.11 hrs, Volume= 205.662 af
Primary = 984.09 cfs @ 13.11 hrs, Volume= 205.662 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
1,100
1,050
1,000
950
900
850
800
750
700
650
600
550
500
450
400
350
300
250
200
150
100
50
o
Link B: Total DA B
Hydrograph
1 984 . 09 c s 1
1 984.09 cf
',
l[nflOw ilArea.=5p.1013 #c
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
[ Inflow
0 Primary

ExistingConditions NRCC 24-hr B NRCC-100yr-24-hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 12
Summary for Link C: Total DA C
Inflow Area = 739.500 ac, 0.00% Impervious, Inflow Depth = 4.75" for NRCC-100yr-24-hr event
Inflow = 1,219.94 cfs @ 13.37 hrs, Volume= 292.418 af
Primary = 1,219.94 cfs @ 13.37 hrs, Volume= 292.418 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
1 ,30° 1,200—/:
1 ,1 00
1 ,000
900
800
700
600
500
400
300
200
100
0
Link C: Total DA C
Hydrograph
1,219.94 cfs
1,219.94 cfs
/0
•
•
.1. .1.. .1.. .1..
Inflow "\rep=739.500 ac
.10
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
[ Inflow
0 Primary

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 13
Time span=0.00-150.00 hrs, dt=0.05 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
Subcatchment Al: DA Al
Subcatchment A2: DA A2
Subcatchment B1: DA B1
Subcatchment Cl: DA Cl
Link A: Total DA A
Link B: Total DA B
Link C: Total DA C
Runoff Area=235.100 ac 0.00% Impervious Runoff Depth=2.75"
Tc=63.3 min CN=78 Runoff=307.86 cfs 53.793 af
Runoff Area=51.000 ac 0.00% Impervious Runoff Depth=2.75"
Tc=22.0 min CN=78 Runoff=121.16 cfs 11.669 af
Runoff Area=520.100 ac 0.00% Impervious Runoff Depth=2.66"
Tc=83.4 min CN=77 Runoff=548.62 cfs 115.137 af
Runoff Area=739.500 ac 0.00% Impervious Runoff Depth=2.66"
Tc=102.9 min CN=77 Runoff=679.56 cfs 163.706 af
Inflow=344.77 cfs 65.462 af
Primary=344.77 cfs 65.462 af
Inflow=548.62 cfs 115.137 af
Primary=548.62 cfs 115.137 af
Inflow=679.56 cfs 163.706 af
Primary=679.56 cfs 163.706 af
Total Runoff Area = 1,545.700 ac Runoff Volume = 344.304 af Average Runoff Depth = 2.67"
100.00% Pervious = 1,545.700 ac 0.00% Impervious = 0.000 ac

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment Al: DA Al
Runoff = 307.86 cfs @ 12.86 hrs, Volume=
53.793 af, Depth= 2.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 235.100 78
235.100 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
63.3 Direct Entry,
"
0
LL
340
320Y/
300-
280 V
260 V
2401(
220�
200 V
180 V
160V
140Y/
120�
100 V
80 V
60=
40
20
0"
Subcatchment Al: DA Al
Hyd rog raph
1307. 6 cf
NRCC 24-hr B
NRCC-1Oyr-24hr Rainfall=5.p4"
........................_...............R.u.nQ.....Ar...ea=....23...100.....a.c
Runoff Woiurne=53.793 of
R.unoffDepth=2.75
Tc=63.3 min
CN=78
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment A2: DA A2
Runoff = 121.16 cfs @ 12.32 hrs, Volume=
11.669 af, Depth= 2.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
51.000 78
51.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.0
Direct Entry,
Subcatchment A2: DA A2
Hyd rog raph
130-Z
120/
110/
100-/
90/
80/
t74-
70-
LL 60/
50-/
40/
30/
20-/
10-
■ Runoff
NRCC 24-hr B
NRCC-10yr-24hr !Rai nfall=5.D4"
Runoff Area=5' .000 ac.......
RunoffVolun e=11....669....af.......
R
:.........................................................................Unoff'Deptih........2.T
T c=22fi rrr''n ..
e 8
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment B1: DA B1
Runoff = 548.62 cfs @ 13.14 hrs, Volume=
115.137 af, Depth= 2.66"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 520.100 77
520.100 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
83.4
600-
550.
500/
450--/
400--/
350.
300/
250--/
200.
150--/
100/
50
Direct Entry,
Subcatchment B1: DA B1
Hyd rog raph
"1 548.62 cfs 1""
NRCC 24-hr B
NRCC-10yr-24hr Rainfall=5.04"
Runoff Area=520.100 ac
Run"off-V"ol um e"=1"115.13"7 of
R"unoffliDepth=2: 66"
Tc=83.4 min
CN=77
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC Page 17
Summary for Subcatchment C1: DA C1
Runoff = 679.56 cfs @ 13.39 hrs, Volume=
163.706 af, Depth= 2.66"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 739.500 77
739.500 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
102.9 Direct Entry,
"
0
LL
750
700/
650/
600/
550/
500/
450/
400/
350/
300/
250/
200/
150/
100/
50/
0"
Subcatchment C1: DA C1
Hyd rog raph
679.56 cfs
NRCC 24-tr 8
:.NRCC 1©yr-24hr Ra�nfatt=5.D4"
Runoff Area=739.500 ac
'Runoff Vbtume=163.706 af
RunoffDepth=2.66"
Tc=1C2.9 min
CN=77
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
■ Runoff

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 18
Summary for Link A: Total DA A
Inflow Area = 286.100 ac, 0.00% Impervious, Inflow Depth = 2.75" for NRCC-10yr-24hr event
Inflow = 344.77 cfs @ 12.79 hrs, Volume= 65.462 af
Primary = 344.77 cfs @ 12.79 hrs, Volume= 65.462 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
:0:
u
0
E
Link A: Total DA A
Hydrograph
380
360 :
340 :.
320 E
300 E
280 E
260 E
240
220 E
200
180 E
160
140 :
120 E
100 E
80 E
60
40 E
20
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
[ Inflow
0 Primary

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 19
Summary for Link B: Total DA B
Inflow Area = 520.100 ac, 0.00% Impervious, Inflow Depth = 2.66" for NRCC-10yr-24hr event
Inflow = 548.62 cfs @ 13.14 hrs, Volume= 115.137 af
Primary = 548.62 cfs @ 13.14 hrs, Volume= 115.137 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
0
Link B: Total DA B
Hydrograph
600
550
500
450
400
350
300
250
200
150
100
50
I 548.62 cfs ]
I 548.62 cfs
Inflow Area=520.100 ac
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
I Inflow
0 Primary

ExistingConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 20
Summary for Link C: Total DA C
Inflow Area = 739.500 ac, 0.00% Impervious, Inflow Depth = 2.66" for NRCC-10yr-24hr event
Inflow = 679.56 cfs @ 13.39 hrs, Volume= 163.706 af
Primary = 679.56 cfs @ 13.39 hrs, Volume= 163.706 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
0
Link C: Total DA C
Hydrograph
750
700
650 :
600
550
500
450
400 :
350 :
300
250
200 :
150
1 00 :
50 :
I 679 . 56 cfs I
79.56 cfs
1
01
Inflbw Area=739.500 ac
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
[ Inflow
0 Primary

STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Appendix D — Proposed Ponds
4 I October 20, 2021

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STORMWATER MANAGEMENT PLAN
GREENSBORO-RANDOLPH MEAGASITE
Appendix E — Proposed Condition Model
Results
October 20, 2021 15

(Al (A2)
11-B
Al -A\
Pond Al
DA Al
<Subca>
A
Outfall A
Reach
A A2
KB1)
B1-A
Pond B1
<B3.U>
Pon B2 DA B1
B
Total DA B
Pon Cl
Total DA C
Routing Diagram for ProposedConditions
Prepared by HDR, Inc, Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 ©2019 HydroCAD Software Solutions LLC

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Area Listing (all nodes)
Area CN Description
(acres) (subcatchment-numbers)
99.300 94 (A1)
404.100 95 (A2, B1)
53.900 76 (A3.U)
37.000 78 (A4.U)
440.500 74 (B2.U, B3.U, C2.U)
533.800 91 (C1)
1,568.600 87 TOTAL AREA
Printed 10/20/2021
Page 2

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Soil Listing (all nodes)
Area Soil Subcatchment
(acres) Group Numbers
0.000 HSG A
0.000 HSG B
0.000 HSG C
0.000 HSG D
1,568.600 Other Al, A2, A3.U, A4.U, B1, B2.U, B3.U, C1, C2.0
1,568.600 TOTAL AREA
Printed 10/20/2021
Page 3

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Ground Covers (all nodes)
Printed 10/20/2021
Page 4
HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment
(acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers
0.000
0.000
0.000 0.000
0.000 0.000
0.000 1,568.600 1,568.600 Al , A2, A3.U, A4.U,
B1, B2.U, B3.U,
C1, C2.0
0.000 1,568.600 1,568.600 TOTAL AREA

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Pipe Listing (all nodes)
Printed 10/20/2021
Page 5
Line# Node In -Invert Out -Invert Length Slope n Diam/Width Height Inside -Fill
Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches)
1 Pond Al
2 Pond A2
3 Pond B1
4 Pond B2
5 Pond C1
6 Pond C2
7 PondA3
680.00
650.00
650.00
609.00
658.00
644.00
622.00
676.00
644.00
640.00
608.00
657.00
643.00
621.00
700.0
400.0
750.0
100.0
400.0
100.0
100.0
0.0057
0.0150
0.0133
0.0100
0.0025
0.0100
0.0100
0.013
0.013
0.013
0.013
0.013
0.013
0.013
60.0
60.0
60.0
66.0
72.0
72.0
72.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 6
Time span=0.00-150.00 hrs, dt=0.05 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentAl: Al -A
SubcatchmentA2: Al-B
SubcatchmentA3.U: DA Al
SubcatchmentA4.U: DA A2
SubcatchmentBl: B1-A
SubcatchmentB2.U: B2
SubcatchmentB3.U: DA B1
SubcatchmentCl: Cl -A
SubcatchmentC2.U: DA Cl
Pond Pond Al: Pond Al
Pond Pond A2: Pond A2
Pond Pond B1: Pond B2
Pond Pond B2: Pond B2
Pond Pond Cl: Pond Cl
Pond Pond C2: Pond C2
Pond PondA3: Pond A3
RunoffArea=99.300 ac 0.00% Impervious Runoff Depth=6.71"
Tc=20.0 min CN=94 Runoff=549.10 cfs 55.487 af
Runoff Area=125.300 ac 0.00% Impervious Runoff Depth=6.82"
Tc=25.0 min CN=95 Runoff=629.70 cfs 71.251 af
RunoffArea=53.900 ac 0.00% Impervious Runoff Depth=4.63"
Tc=30.0 min CN=76 Runoff=184.14 cfs 20.811 af
RunoffArea=37.000 ac 0.00% Impervious Runoff Depth=4.86"
Tc=22.0 min CN=78 Runoff=154.43 cfs 14.977 af
RunoffArea=278.800 ac 0.00% Impervious Runoff Depth=6.82"
Tc=30.0 min CN=95 Runoff=1,275.64 cfs 158.538 af
RunoffArea=26.000 ac 0.00% Impervious Runoff Depth=4.41"
Tc=30.0 min CN=74 Runoff=84.71 cfs 9.556 af
RunoffArea=69.500 ac 0.00% Impervious Runoff Depth=4.41"
Tc=30.0 min CN=74 Runoff=226.43 cfs 25.544 af
RunoffArea=533.800 ac 0.00% Impervious Runoff Depth=6.35"
Tc=30.0 min CN=91 Runoff=2,356.30 cfs 282.572 af
Runoff Area=345.000 ac 0.00% Impervious Runoff Depth=4.41"
Tc=60.0 min CN=74 Runoff=752.58 cfs 126.799 af
Peak Elev=688.77' Storage=20.963 af Inflow=549.10 cfs 55.487 af
Outflow=217.66 cfs 55.487 af
Peak EIev=660.54' Storage=24.890 af Inflow=629.70 cfs 71.251 af
Outflow=268.11 cfs 71.251 af
Peak EIev=665.00' Storage=73.873 af Inflow=1,275.64 cfs 158.538 af
Outflow=334.20 cfs 158.538 af
Peak EIev=620.00' Storage=61.086 af Inflow=390.92 cfs 168.094 af
Outflow=328.53 cfs 165.451 af
Peak EIev=674.60' Storage=147.668 af Inflow=2,356.30 cfs 282.572 af
Outflow=503.77 cfs 282.572 af
Peak EIev=655.44' Storage=95.136 af Inflow=503.77 cfs 282.572 af
Outflow=395.62 cfs 232.005 af
Peak EIev=635.64' Storage=45.839 af Inflow=653.35 cfs 147.549 af
Outflow=444.01 cfs 146.949 af

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 7
Link A: Outfall A
Link B: Total DA B
Link C: Total DA C
Inflow=516.08 cfs 161.927 af
Primary=516.08 cfs 161.927 af
Inflow=379.98 cfs 190.995 af
Primary=379.98 cfs 190.995 af
Inflow=752.58 cfs 358.804 af
Primary=752.58 cfs 358.804 af
Total Runoff Area = 1,568.600 ac Runoff Volume = 765.536 af Average Runoff Depth = 5.86"
100.00% Pervious = 1,568.600 ac 0.00% Impervious = 0.000 ac

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment Al: Al -A
Runoff = 549.10 cfs @ 12.29 hrs, Volume=
55.487 af, Depth= 6.71"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
99.300 94
99.300 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
20.0
600-
550-
500
4501-
400-
350—
300—/
250�
Direct Entry,
Subcatchment Al: Al -A
Hydrograph
—
200—
-
1501
100=
50-
549.10 cfs
7
4
1
1
4
1
II II II II II
r r H
NRCC 24-hr B
NRCC-100yr-24hr 14ainfII=742"
RunoffArea=99 300-ac-
R rno#LVoI-Ume=¢5 of -
Runoff Depth=6J71"
Tc=20.0
✓ 1
7
CN=94
r 4
L 1 L
10 20 30 40 50 60 70 80 90 100 110 120 130
Time (hours)
140
150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment A2: Al-B
Runoff = 629.70 cfs @ 12.35 hrs, Volume=
71.251 af, Depth= 6.82"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
* 125.300 95
125.300 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
25.0 Direct Entry,
Subcatchment A2: Al-B
Hydrograph
700
650J
600:-
5507-
5001▪ -
450-
4001-
350-
300�
250�'
200J
150=
100-
50-
0
r
4
✓
1629.70 0
-
r
1
r
r
r
r
r
f+FRC 24 fit'-B-
NR-9C-1QOyr- 4hrRainfiH=-742"-
Runoff-Aroa=1-.5.300-ac-
RunoffrVoly mc= 7 i.251- af _
Runoff Depth=6J82"
✓
✓
-1 r
Tc=25.0 ruin
CN'1=95
r l
0 10 20 30 40 50 60 70 80 90
Time (hours)
100
110 120
130
140
150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 10
Summary for Subcatchment A3.U: DA Al
Runoff = 184.14 cfs @ 12.42 hrs, Volume=
20.811 af, Depth= 4.63"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
53.900 76
53.900 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
Subcatchment A3.U: DA Al
Hydrograph
200" I
r
1
190— i 1184.14 cf
180J _ _
170
1607:-'
150=" - -
140��' --
130�k__
120� ---
1 1101 r--
3
a 90
zz
80=
70= I __
60= -
50=
40"/ --
30�
20-
1 0-
0'
r
r
✓
✓
NRCC 24-lir B
1
4
4
✓
-NRCC-i9Oyr 4hrf a-infl11=742"-
RunofiArea=53 90tYac-
r
R�inoffrLVolyme=i0.81) af
Runoff-Depth=4�'63" -
Tc=3tY.0 rain -
✓
r CNr=76
r
✓
4
✓
✓
✓
✓
✓ _J
✓ -4
✓
✓ r
✓ r
10 20 30 40 50 60 70 80 90 100 110 120 130 140
Time (hours)
150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 11
Summary for Subcatchment A4.U: DA A2
Runoff = 154.43 cfs @ 12.32 hrs, Volume=
14.977 af, Depth= 4.86"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
37.000 78
37.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.0 Direct Entry,
Subcatchment A4.U: DA A2
Hydrograph
170_
T
1154.43 cf
1507"
140�
120-
11 Or-'
100-
90J
80 /
70J�m-
604
50=
40= _
30_
20J
10J
0
r r r r r
NRCC 24-Ihr B
NRCC-1QOyr-24hr 14ainf1II=742"
Runoff Area=37.000 ac
t
4-
RunoffrVoaf -
▪ Runoff-Depth=41186" -
Tc=22:0 !Tan -
L
L
t
✓ t
L J
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 12
Summary for Subcatchment B1: B1-A
Runoff = 1,275.64 cfs @ 12.41 hrs, Volume=
158.538 af, Depth= 6.82"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
* 278.800 95
278.800 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
Subcatchment B1: B1-A
Hydrograph
1,400-<
1, 300�
1,200-
1,100-
1,0007-
r
900J
800-
700
600J
5001_
400
300-
200-
100
0
L
1,275.64 cfs
r
L
L L L L
NRCC 24-Fir-B-
NR4-C400yr- 4hr- -
Eunoff_9rea=27. 80O-ac -
RunoffVolurne=18.5318 af
Runoff Depth=6.182"
r r r r
Tc=30.0 rein
CN=95
r
1
r
r
10 20 30 40 50 60 70 80 90
Time (hours)
100
110
120 130
140 150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 13
Summary for Subcatchment B2.U: B2
Runoff = 84.71 cfs @ 12.42 hrs, Volume=
9.556 af, Depth= 4.41"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
26.000 74
26.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0
90"
85
80 - -
75 I __
70_'�--
65
60 k--
55 I __
50 --
45 I__
40' __
35
30=' 11
25
20 --
15='
10 --
5 1
Direct Entry,
Subcatchment B2.U: B2
Hydrograph
I T
1 84.71 cfs
r r 1 r
7
NRCC 24-I r$ -
i4R .`C=1-00yr- 4fhr tainfall=7.42"
rRunoff Area=$6.00O ac
L
Runoff Volume=9.550 af
+ Run-off-Depth=44i"-
▪ 4- Tc=30-0 rn in -
_I L
CN`=74
L L +
L J
L L
10 20 30 40 50 60 70 80 90
Time (hours)
100
110
120
130
140
150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 14
Summary for Subcatchment B3.U: DA B1
Runoff = 226.43 cfs @ 12.42 hrs, Volume=
25.544 af, Depth= 4.41"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
69.500 74
69.500 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
250-
240
230
220
210
200
190-
180
170
160
150
140J
130
0 120-�
LL 110=
100
90=
80�
70=
60J
50=
40J
30=
20°
10J
0-
0 10 20 30 40 50 60 70 80 90
Time (hours)
Subcatchment B3.U: DA B1
Hydrograph
L 1 L 1 1 1 1 1 1 L 1 L L
T r 1 r I T I T 1 7 r 7 r T
r i r
r
T i T
NRCC 24-,r B
NR9C=t00yr-4hr 1,2ainflH=7,42"-
Runoff-A4-ea=6S- 50b-ac-
Rinoff� or me=g5 544 af-
Runoff-Dejth=441 "-
Tc=pA0 in-
1 L 1 1 1 1 1 1 L 1 L C1�%74
r 1 r 1 r I Y 1 7 r T r -1
L 1 L 1 1 1 1 1 1 L 1 L 1
4
4 i -4 4- 4 4- -4
100
110 120
130
140
150

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 15
Summary for Subcatchment Cl: Cl-A
Runoff = 2,356.30 cfs @ 12.41 hrs, Volume= 282.572 af, Depth= 6.35"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
* 533.800 91
533.800 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
0
LL
Subcatchment C1: Cl-A
Hydrograph
2,600; ,
2,500
2,400
2,300�
2,200
2,100
2,000,
1,900=
1,800,
1, 700-;'
1,600,
1,500
1,400
1,300-;-
1 ,200
1,100�
1,000-
900
800
700
600
500
400
300
200
100
0
0
L L L
L
L
L I L L L J
1 1
L L L
2,356.30 cfs
1 1
L 1
L ▪ 1
1 I T
L I L
L
L
L
L
L
L L r4RC1 2_4-LirB _
NRcC4OIOyr-- 4-fir F ainfal1=7J42" -
FRtmotf-Area=5 80d-ac -
-Run-off 4olume=2-2.57 af -
Runof f Depl'th=6 35"
Tc=pO-Om -
+ + L r 'r CN9i -
r--- I Ir
✓ -t I + I + I Y 1 Y 7 r -
I 1 I 1 I 1 I 1 I 1 1 I 1
L 1 I 1 I 1 I L I L J L J
I 1 I T I T I T I 1 1 I 1
L 1 I 1 I 1 I L I L J L J
10 20 30 40 50 60 70 80 90
Time (hours)
100
110
120 130
140 150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 16
Summary for Subcatchment C2.U: DA C1
Runoff = 752.58 cfs @ 12.83 hrs, Volume=
126.799 af, Depth= 4.41"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Area (ac) CN Description
* 345.000 74
345.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
60.0 Direct Entry,
Subcatchment C2.U: DA C1
Hydrograph
800J k 752.58 cfs
7507:'
700-
650 -
600-
550
500
N = fi
4507=-
0 400i'
a 350-
-
300=
250=
200-
150-
100-
50
0
T
—
4
rt
RCC Z4 Iill _C_
.NR C-1QOyr-44hr inflU=J 42"-
Runoff-Area=345.00d-ac-
Rtxooff-\oFuroraf-
rt
Runoff-Depth= 141"-
Tc=50Y.0 rain
7
4
4
CN'*74
4 -4
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 17
Inflow Area =
Inflow =
Outflow =
Primary =
Summary for Pond Pond Al: Pond Al
99.300 ac, 0.00% Impervious, Inflow Depth = 6.71" for NRCC-100yr-24hr event
549.10 cfs @ 12.29 hrs, Volume= 55.487 af
217.66 cfs @ 12.63 hrs, Volume= 55.487 af, Atten= 60%, Lag= 20.8 min
217.66 cfs @ 12.63 hrs, Volume= 55.487 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 688.77' @ 12.63 hrs Surf.Area= 3.387 ac Storage= 20.963 af
Plug -Flow detention time= 131.5 min calculated for 55.469 af (100% of inflow)
Center -of -Mass det. time= 131.9 min (908.7 - 776.7 )
Volume
Invert Avail.Storage Storage Description
#1 680.00' 44.210 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area
(feet) (acres)
680.00 0.460
682.00 1.540
684.00 2.620
685.00 2.980
690.00 3.520
695.00 4.080
Device Routing
Inc.Store Cum.Store
(acre-feet) (acre-feet)
0.000 0.000
2.000 2.000
4.160 6.160
2.800 8.960
16.250 25.210
19.000 44.210
Invert
Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
680.00' 60.0" Round Culvert
L= 700.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 680.00' / 676.00' S= 0.0057'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
680.00' 24.0" Vert. Orifice/Grate C= 0.600
686.00' 24.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=217.61 cfs @ 12.63 hrs HW=688.77' (Free Discharge)
4-1=Culvert (Barrel Controls 217.61 cfs @ 11.08 fps)
AL2=Orifice/Grate (Passes < 42.15 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 361.06 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 18
600J
550�
500J
LL
250J
Elevation (feet)
200J
150J
100
50
695/
6947-
4-
693�
692—
k
691
690—/
689�
4-
6887-
687—/
= r
6867- r
685—'
684- /
--
683-
682.
681J
680
Pond Pond Al: Pond Al
Hyd rog raph
549.10 cf
17.66 cfs
pv
r
r
r
r
r
r
✓ inf tov Ara=99 Q0- pc- -
▪ Reak Flew=6$&.-77'
Stprage=2o.$63 ';ef- -
r r
r
-r
r
r
r
H
r
10 20 30 40 50 60 70 80 90
Time (hours)
100
110 120
Pond Pond Al: Pond Al
Stage -Discharge
.r.
Sharp -Crested Rectangular Weir
�/ 1
i 1
L
Culv
II
r
r
130
140
150
0
50
100
150
Discharge (cfs)
200 250
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
1
Pond Pond Al: Pond Al
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 19
3
4
695-
694
693-
692-
691 J
6907-
6897-
688-
0
687J
686J
w
685-
684=
683
682-
681-
680
0
L
1
4
J
I
I I 0.
• L jL
L J + L 1 1
1
L L J + L
• Lr r
+ --+ +----+
L L L L L L
i
I L L
r
71
+ - - - + - - - + + - - - - +
L L L
Custom Stage Data
5 10 15
20 25 30 35 40
Storage (acre-feet)
u Surface
• Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 20
Inflow Area =
Inflow =
Outflow =
Primary =
Summary for Pond Pond A2: Pond A2
125.300 ac, 0.00% Impervious, Inflow Depth = 6.82" for NRCC-100yr-24hr event
629.70 cfs @ 12.35 hrs, Volume= 71.251 af
268.11 cfs @ 12.73 hrs, Volume= 71.251 af, Atten= 57%, Lag= 23.0 min
268.11 cfs @ 12.73 hrs, Volume= 71.251 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 660.54' @ 12.73 hrs Surf.Area= 4.591 ac Storage= 24.890 af
Plug -Flow detention time= 109.5 min calculated for 71.228 af (100% of inflow)
Center -of -Mass det. time= 109.5 min (886.5 - 776.9 )
Volume
Invert Avail.Storage Storage Description
#1 650.00' 74.970 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area
(feet) (acres)
650.00 0.030
652.00 0.650
654.00 1.550
656.00 2.640
658.00 4.100
660.00 4.510
670.00 6.000
Device Routing
Inc.Store Cum.Store
(acre-feet) (acre-feet)
0.000 0.000
0.680 0.680
2.200 2.880
4.190 7.070
6.740 13.810
8.610 22.420
52.550 74.970
Invert
Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
650.00' 60.0" Round Culvert
L= 400.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 650.00' / 644.00' S= 0.0150'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
650.00' 24.0" Vert. Orifice/Grate C= 0.600
658.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=268.06 cfs @ 12.73 hrs HW=660.54' (Free Discharge)
4-1=Culvert (Inlet Controls 268.06 cfs @ 13.65 fps)
AL2=Orifice/Grate (Passes < 46.72 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 529.25 cfs potential flow)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
700-'
650�
600-:"
550�
500
450�
w 400�
U -
3 350—_'
o -
a 300—_'
250-4'
200—
150—
100"
50-
0
Elevation (feet)
Pond Pond A2: Pond A2
Hyd rog raph
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 21
r
268.11 cfs
+--- -hi --------+---+ +
Ir r r Ir I Ir
-Inflow ikrea=1 5.400 ac -
PeakiElev=660.44'
Storage_ 24F8S0!af_-
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
670- r
669J
668'"
667J
666'"
665J
664'"
663J
662-
661"z
660�
659J
658'
657= +
656' +--
655 _
654'
653=
652-
651_ C
650
r
r
Pond Pond A2: Pond A2
Stage -Discharge
L L L
L
L Sharp -Crested Rectangular Weir
r--
r
+ + +
✓ + r
r r
r
r
r
0
100
150 200 250
Discharge (cfs)
300
350
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
670
669
668J
667
666
665
664
663
662
661H�
660H
659
658-
657J
656
655
654=
653-
652=
651 Custom
1
Pond Pond A2: Pond A2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3 4
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 22
5
6
0 5 10 15 20 25
30 35 40 45
Storage (acre-feet)
50 55
60
65
70
Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 23
Summary for Pond Pond B1: Pond B2
Inflow Area = 278.800 ac, 0.00% Impervious, Inflow Depth = 6.82" for NRCC-100yr-24hr event
Inflow = 1,275.64 cfs @ 12.41 hrs, Volume= 158.538 of
Outflow = 334.20 cfs @ 13.08 hrs, Volume= 158.538 af, Atten= 74%, Lag= 40.6 min
Primary = 334.20 cfs @ 13.08 hrs, Volume= 158.538 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 665.00' @ 13.08 hrs Surf.Area= 10.222 ac Storage= 73.873 af
Plug -Flow detention time= 240.0 min calculated for 158.538 af (100% of inflow)
Center -of -Mass det. time= 239.1 min (1,020.7 - 781.6 )
Volume Invert Avail.Storage Storage Description
#1 650.00' 290.310 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
650.00 0.750 0.000 0.000
652.00 1.630 2.380 2.380
654.00 2.650 4.280 6.660
656.00 3.770 6.420 13.080
658.00 5.000 8.770 21.850
660.00 6.360 11.360 33.210
662.00 7.580 13.940 47.150
664.00 9.380 16.960 64.110
666.00 11.070 20.450 84.560
668.00 13.160 24.230 108.790
670.00 13.810 26.970 135.760
680.00 17.100 154.550 290.310
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
650.00' 60.0" Round Culvert
L= 750.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 650.00' / 640.00' S= 0.0133'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
650.00' 24.0" Vert. Orifice/Grate C= 0.600
660.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=334.19 cfs @ 13.08 hrs HW=664.99' (Free Discharge)
4-1=Culvert (Inlet Controls 334.19 cfs @ 17.02 fps)
AL2=Orifice/Grate (Passes < 56.59 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 1,460.13 cfs potential flow)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Pond Pond B1: Pond B2
Hyd rog raph
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 24
1 ,400-„'i 1,275.64 cfs
1,300E"�
1,200�
/
1,100�� �r I
1,000 1
�1 900/" -H
H 800-
700- -
LL -
600"
5007:"
400�
- I 334.20 cfs
300=
200�'
100J
Elevation (feet)
0
680/
6787: 1
676E'
674—
6727-
670— I
668E"
6667-
664—
6627:
6607--
I n#Icyw *m 0=278-.0fl0- c-
L
Peak iE1eii=66L O1-
Storaoe,73.873af
4 4
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
i
4
r
L
-
658
--
656-
654.
652-'
650
0
Time (hours)
Pond Pond B1: Pond B2
Stage -Discharge
✓
4
7
L
✓
4
Sharp -Crested Rectangular Weir
i
4
i
i
it
+
J
100 150 200 250 300 350 400 450
Discharge (cfs)
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
680:
678�
6761:'
674-
672J
6707-
6687-
6667:'
o -
664J
. 662J
660-
658:
656=
654
652
650
0 1 2
+I
II
Pond Pond B1: Pond B2
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 25
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
'' '1'I' "'I"'I"'II' 'r'I"'I"11"'A"'I1"'I1..I'1'
++---I+---I+
IL I 1I I I I I L IL
r 1 1 1 4
1 I Ir
It + + + ++ I+
I 1 I II
IL
4
11- r1 Ir Ir
+ 1 I 1 I+11
IL
+I III 111
J 1 LL IL IL
1
I
L 1
I II
L LL u
0 20 40 60 80 100 120 140 160 180 200
Storage (acre-feet)
220
L 1
240 260
280
ti
1 L L
• Surface`
• Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 26
Summary for Pond Pond B2: Pond B2
Inflow Area = 304.800 ac, 0.00% Impervious, Inflow Depth = 6.62" for NRCC-100yr-24hr event
Inflow = 390.92 cfs @ 12.52 hrs, Volume= 168.094 af
Outflow = 328.53 cfs @ 13.99 hrs, Volume= 165.451 af, Atten= 16%, Lag= 87.7 min
Primary = 328.53 cfs @ 13.99 hrs, Volume= 165.451 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 614.00' Surf.Area= 4.900 ac Storage= 28.400 af
Peak Elev= 620.00' @ 13.99 hrs Surf.Area= 6.000 ac Storage= 61.086 af (32.686 af above start)
Plug -Flow detention time= 824.7 min calculated for 137.005 af (82% of inflow)
Center -of -Mass det. time= 523.6 min (1,534.1 - 1,010.5 )
Volume Invert Avail.Storage Storage Description
#1 608.00' 61.100 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
608.00 4.500 0.000 0.000
610.00 4.700 9.200 9.200
612.00 4.800 9.500 18.700
614.00 4.900 9.700 28.400
620.00 6.000 32.700 61.100
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
609.00' 66.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 609.00' / 608.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 23.76 sf
614.00' 8.0" Vert. Orifice/Grate C= 0.600
618.00' 40.0' long Sharp -Crested Rectangular Weir O End Contraction(s)
Primary OutFlow Max=328.53 cfs @ 13.99 hrs HW=620.00' (Free Discharge)
4-1=Culvert (Inlet Controls 328.53 cfs @ 13.83 fps)
AL2=Orifice/Grate (Passes < 4.00 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 369.29 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 27
4207:-/
400
380
360�
340
320
300
280
260
240
3 220J
0 200=
180
160
140=
120=
100=
80'
60-
40
20-
0-�
620
618
617
616
615
0 614
0 613
w
612
611
610
608
Pond Pond B2: Pond B2
Hyd rog raph
L L 1 L _ J L i 1 L L 1 1
--+--------+---+--------+--------+---+--------+---+----I----+
390.92 cfs
328.53 cfs
+
+
Inflow 4re=34.8O0 6--
+ Storaga6 LOS6Iaf--
i
i
4-
i r i
L L
0 10 20 30 40
50 60 70 80 90
Time (hours)
100
110 120
Pond Pond B2: Pond B2
Stage -Discharge
Sharp -Crested RectangiEM
L
130
140
150
0
Orifice/rate
r
+
L
+
50
100
150 200
Discharge (cfs)
250
300
U Inflow
• Primary
❑ Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
620
619:
618-
617:-
616-
615:-
614-
613:
612-
609-
608
1
Custom Stage Data
Pond Pond B2: Pond B2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3 4
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 28
5
0 5 10 15 20 25 30 35
Storage (acre-feet)
40
45
50
55
60
6
D Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 29
Summary for Pond Pond Cl: Pond C1
Inflow Area = 533.800 ac, 0.00% Impervious, Inflow Depth = 6.35" for NRCC-100yr-24hr event
Inflow = 2,356.30 cfs @ 12.41 hrs, Volume= 282.572 af
Outflow = 503.77 cfs @ 13.22 hrs, Volume= 282.572 af, Atten= 79%, Lag= 48.4 min
Primary = 503.77 cfs @ 13.22 hrs, Volume= 282.572 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 674.60' @ 13.22 hrs Surf.Area= 14.827 ac Storage= 147.668 af
Plug -Flow detention time= 377.6 min calculated for 282.478 af (100% of inflow)
Center -of -Mass det. time= 378.3 min (1,175.9 - 797.6 )
Volume Invert Avail.Storage Storage Description
#1 658.00' 460.200 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
658.00 0.760 0.000 0.000
660.00 2.920 3.680 3.680
662.00 5.960 8.880 12.560
664.00 8.150 14.110 26.670
666.00 9.340 17.490 44.160
668.00 10.650 19.990 64.150
670.00 12.000 22.650 86.800
672.00 13.000 25.000 111.800
674.00 14.200 27.200 139.000
676.00 16.300 30.500 169.500
678.00 17.500 33.800 203.300
680.00 19.900 37.400 240.700
690.00 24.000 219.500 460.200
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
658.00' 72.0" Round Culvert
L= 400.0' RCP, groove end w/headwall, Ke= 0.200
Inlet / Outlet Invert= 658.00' / 657.00' S= 0.0025'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
658.00' 24.0" Vert. Orifice/Grate C= 0.600
668.00' 60.0' long Sharp -Crested Rectangular Weir End Contraction(s)
Primary OutFlow Max=503.75 cfs @ 13.22 hrs HW=674.60' (Free Discharge)
4-1=Culvert (Barrel Controls 503.75 cfs @ 17.82 fps)
AL2=Orifice/Grate (Passes < 59.74 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 3,250.58 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 30
N
4,3
0
LL
Pond Pond Cl: Pond C1
Hyd rog raph
2,600_ / 1 2,356.30 cfs
2,400-1_" �r
2,200
2,000:"
1,8007:-
1,600�
1, 4001-
1,200� /r
1,0007: //T
800J
600503.77 cfs
4001
200-
690-
688J
686J
6847-
682J
680-:"
678-
w
676�
0 6747-
> 6727'
w 670�
668J
666J
664=
662=
660:
658
L
L
• nflgw Are4=543:8-00
Peak ;EIev=6 4.60'
Storage=147.668 of
L
L
10 20 30 40 50 60 70 80 90
Time (hours)
L
100 110 120 130 140 150
Pond Pond Cl: Pond C1
Stage -Discharge
Sharp -Crested Rectangular Weir
4-1
i
i
it
i
i
i
i
0
100
200 300 400 500 600 700
Discharge (cfs)
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
Pond Pond Cl: Pond C1
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 31
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
690
688
686-
684-
682�
680�
678�
676�
674-
672�
670-
668-
666�
664_
662-
660
658 .
11
1
4
Custom Stag
1 1 r
1I--+--r----1--rlrI--R--r
- +-+----+I--+--+-I-I--+--+I--+
- 1' - - - I - - 1 - - + - - I - I - I - - 4
-1' _ ---I--JI-_ 1--�
1
- 1
11
1I
44
44
u
u
r
0
50 100 150 200 250 300 350 400 450
Storage (acre-feet)
• Surface`
• Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 32
Summary for Pond Pond C2: Pond C2
Inflow Area = 533.800 ac, 0.00% Impervious, Inflow Depth = 6.35" for NRCC-100yr-24hr event
Inflow = 503.77 cfs @ 13.22 hrs, Volume= 282.572 af
Outflow = 395.62 cfs @ 15.90 hrs, Volume= 232.005 af, Atten= 21%, Lag= 161.3 min
Primary = 395.62 cfs @ 15.90 hrs, Volume= 232.005 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 630.00' Surf.Area= 0.000 ac Storage= 0.000 af
Peak Elev= 655.44' @ 15.90 hrs Surf.Area= 9.544 ac Storage= 95.136 af
Plug -Flow detention time= 823.1 min calculated for 232.005 af (82% of inflow)
Center -of -Mass det. time= 594.6 min (1,770.5 - 1,175.9 )
Volume Invert Avail.Storage Storage Description
#1 644.00' 190.900 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
644.00 6.000 0.000 0.000
646.00 7.000 13.000 13.000
648.00 8.000 15.000 28.000
650.00 8.900 16.900 44.900
655.00 9.500 46.000 90.900
660.00 10.000 48.750 139.650
665.00 10.500 51.250 190.900
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
644.00' 72.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 644.00' / 643.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
650.00' 10.0" Vert. Orifice/Grate C= 0.600
653.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=395.62 cfs @ 15.90 hrs HW=655.44' (Free Discharge)
4-1=Culvert (Inlet Controls 395.62 cfs @ 13.99 fps)
AL2=Orifice/Grate (Passes < 5.89 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 500.02 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 33
550:"
500-
450—
400
350—
- 300—
3 =
LT 250-
200-
150-
w
0
w
w
100
50
665 ,
664
663=
662/ )
661'
660
659
658/
657�
656'
655=
654/
653J
652-
651 -
650-
Stage -Discharge
Pond Pond C2: Pond C2
Hyd rog raph
503.77 cfs
395.62 cfs
Inflow Area=5:33.000 Tac
10 20 30 40 50 60 70 80 90
Time (hours)
100
Peak
Elev=655.44'
Storage?95.136raf
110 120
Pond Pond C2: Pond C2
i
r
r
1
r
r
r
L-
r
Sharp -Crested Rectangular
7 r r
7
130
140
150
7
649
648
647
646,
645
644
0 50 100
r
r
r
150 200 250 300 350 400 450 500 550
Discharge (cfs)
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
665-
664
663
662
661-
660'
659
658
657
656
655�
654
653='
652=
651-
650
z 649 '
648=
647-
646
645
644
1
2
Pond Pond C2: Pond C2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
3 4 5 6 7
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 34
8
9
10
++-+---It--+--+1---+ 1 1 t ++ ++
4-11 4- 1
TI T 1
r11 1i T 11 T 1 1 r 1
--+I----+-I--- 1 1 1 - - --&-- --+I1
1 1 I 1 J 1 L I L L_ J___ LL-- 1
r 1 1 rr-r---rr
+--+I---+-+-1---+-I--I---++
1--11---1-J-1---L-I
Ti1T
4 - - 1 I
T1
L
1
T r
1 11 L uL ___1 1
t _J
11 r rr
-
--rr
It + +1 + I + ++ ++
L L_ J LL 1 JI 1 I
1it 4 4 4 41
Ti
11 r T
4-
1
1 T I
1 J 1 L I
t1r+y-1---r
11 4 11 1
II I II
11 - T T 1I T
L L J 1L 1 41 1
r r + + +1
4
I I
T
r--
1
11 tr+---r+-+
+
1
4
-r
1
r
1
L
+
Custom Stage Data
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
Storage (acre-feet)
• Surface
• Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 35
Summary for Pond PondA3: Pond A3
Inflow Area = 278.500 ac, 0.00% Impervious, Inflow Depth = 6.36" for NRCC-100yr-24hr event
Inflow = 653.35 cfs @ 12.47 hrs, Volume= 147.549 af
Outflow = 444.01 cfs @ 13.28 hrs, Volume= 146.949 af, Atten= 32%, Lag= 48.5 min
Primary = 444.01 cfs @ 13.28 hrs, Volume= 146.949 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 628.00' Surf.Area= 3.200 ac Storage= 17.800 af
Peak Elev= 635.64' @ 13.28 hrs Surf.Area= 4.127 ac Storage= 45.839 af (28.039 af above start)
Plug -Flow detention time= 382.6 min calculated for 129.106 af (88% of inflow)
Center -of -Mass det. time= 257.5 min (1,145.3 - 887.8 )
Volume Invert Avail.Storage Storage Description
#1 622.00' 65.750 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
622.00 2.800 0.000 0.000
626.00 3.000 11.600 11.600
628.00 3.200 6.200 17.800
630.00 3.500 6.700 24.500
635.00 4.000 18.750 43.250
640.00 5.000 22.500 65.750
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
622.00' 72.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 622.00' / 621.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
628.00' 7.0" Vert. Orifice/Grate C= 0.600
631.00' 40.0' long Sharp -Crested Rectangular Weir End Contraction(s)
Primary OutFlow Max=443.94 cfs @ 13.28 hrs HW=635.63' (Free Discharge)
4-1=Culvert (Inlet Controls 443.94 cfs @ 15.70 fps)
AL2=Orifice/Grate (Passes < 3.49 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 1,274.36 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 36
700-
6507-
600�
5507:"
500
4507
400�
350�'
• 3007-
250:"
200-_-
150:
100=
Elevation (feet)
50=
0
Pond PondA3: Pond A3
Hyd rog raph
653.35 cfs
444.01 cfs
i
InfIpwAre= 278.0OQ ac
Peak Eiev=633-5- 4'
Storage=45.8a9lof
L
t
L
r
it
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
Pond PondA3: Pond A3
Stage -Discharge
6404 '_
639�
638� j
6377-:
636::
635::'
-
6347" fi
6331.'
632�
631:
630
629
628=Ir
627=
J'
626
625
624
r
4-
-1
L
✓
-1
Sharp -Crested Rectangular Weir L
L i L L
r
L
L
4-
r
r
623J
622 "
I•
1
0 50 100 • 150 200 250 300 350 400 450 • 500
Discharge (cfs)
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
640J
639-
638J
637
636
635
634-
633-
632-
631-
630-
629=
628J
627
626J
625-
624-
623=
622
1
Pond PondA3: Pond A3
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3
Custom Stage Data
i
i
i
0 5 10 15 20 25 30 35 40
Storage (acre-feet)
45
50
NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Printed 10/20/2021
Page 37
55
4
60
65
5
D Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 38
Summary for Link A: Outfall A
Inflow Area = 315.500 ac, 0.00% Impervious, Inflow Depth > 6.16" for NRCC-100yr-24hr event
Inflow = 516.08 cfs @ 12.46 hrs, Volume= 161.927 af
Primary = 516.08 cfs @ 12.46 hrs, Volume= 161.927 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
550—
500-
450—
400-
350—
300—
0
u 250—
200—
150-
100—
50-
Link A: Outfall A
Hyd rog raph
1516.08 cfs
516.08 cfs
10 20
Inflow Area=3,15. 00 Tac
30 40 50 60 70 80 90
Time (hours)
100 110 120 130 140 150
C Inflow
❑ Primary

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 39
Summary for Link B: Total DA B
Inflow Area = 374.300 ac, 0.00% Impervious, Inflow Depth > 6.12" for NRCC-100yr-24hr event
Inflow = 379.98 cfs @ 13.06 hrs, Volume= 190.995 af
Primary = 379.98 cfs @ 13.06 hrs, Volume= 190.995 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
420,'
400
380
360H-
340
320
300
280
260
240
220 -
200
180
160
140
120
Link B: Total DA B
Hyd rog raph
1
379.98 cfs
79.98 cfs
1
1
L 1 1 1
L 1
T T
i rrf 1pw AYe4=374. 00 c- -
+
T T i T T T T
L 1 1 I L 1 L 1 1
1 1 1
r T T T
L 1 1 I L 1 L 1 1
T T i T i r T i T T i
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
C Inflow
❑ Primary

ProposedConditions NRCC 24-hr B NRCC-100yr-24hr Rainfall=7.42"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 40
Summary for Link C: Total DA C
Inflow Area = 878.800 ac, 0.00% Impervious, Inflow Depth > 4.90" for NRCC-100yr-24hr event
Inflow = 752.58 cfs @ 12.83 hrs, Volume= 358.804 af
Primary = 752.58 cfs @ 12.83 hrs, Volume= 358.804 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
800-
750
700
650 '
600 '
550-
500-
=
4507-
0 400i
a 350=
300�
250�
200�
150 '
100�
50=
0
Link C: Total DA C
Hyd rog raph
752.58 cf
52.58 c
10
7 7
Inflow 4Are =&7 $OaaC--
1
40 50 60 70 80 90
Time (hours)
1
1
rt
C Inflow
❑ Primary

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 41
Time span=0.00-150.00 hrs, dt=0.05 hrs, 3001 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method
SubcatchmentAl: Al -A
SubcatchmentA2: Al-B
SubcatchmentA3.U: DA Al
SubcatchmentA4.U: DA A2
SubcatchmentBl: B1-A
SubcatchmentB2.U: B2
SubcatchmentB3.U: DA B1
SubcatchmentCl: Cl -A
SubcatchmentC2.U: DA Cl
Pond Pond Al: Pond Al
Pond Pond A2: Pond A2
Pond Pond B1: Pond B2
Pond Pond B2: Pond B2
Pond Pond Cl: Pond Cl
Pond Pond C2: Pond C2
Pond PondA3: Pond A3
Runoff Area=99.300 ac 0.00% Impervious Runoff Depth=4.35"
Tc=20.0 min CN=94 Runoff=364.42 cfs 35.975 af
Runoff Area=125.300 ac 0.00% Impervious Runoff Depth=4.46"
Tc=25.0 min CN=95 Runoff=420.37 cfs 46.561 af
RunoffArea=53.900 ac 0.00% Impervious Runoff Depth=2.57"
Tc=30.0 min CN=76 Runoff=102.04 cfs 11.537 af
RunoffArea=37.000 ac 0.00% Impervious Runoff Depth=2.75"
Tc=22.0 min CN=78 Runoff=87.90 cfs 8.466 af
RunoffArea=278.800 ac 0.00% Impervious Runoff Depth=4.46"
Tc=30.0 min CN=95 Runoff=851.32 cfs 103.601 af
RunoffArea=26.000 ac 0.00% Impervious Runoff Depth=2.40"
Tc=30.0 min CN=74 Runoff=45.75 cfs 5.192 af
RunoffArea=69.500 ac 0.00% Impervious Runoff Depth=2.40"
Tc=30.0 min CN=74 Runoff=122.30 cfs 13.878 af
RunoffArea=533.800 ac 0.00% Impervious Runoff Depth=4.02"
Tc=30.0 min CN=91 Runoff=1,527.46 cfs 178.864 af
RunoffArea=345.000 ac 0.00% Impervious Runoff Depth=2.40"
Tc=60.0 min CN=74 Runoff=405.40 cfs 68.891 af
Peak EIev=687.06' Storage=15.321 af Inflow=364.42 cfs 35.975 af
Outflow=122.66 cfs 35.975 af
Peak EIev=658.98' Storage=17.934 af Inflow=420.37 cfs 46.561 af
Outflow=170.15 cfs 46.561 af
Peak EIev=662.00' Storage=47.151 af Inflow=851.32 cfs 103.601 af
Outflow=291.40 cfs 103.601 af
Peak EIev=619.49' Storage=58.091 af Inflow=318.02 cfs 108.793 af
Outflow=242.91 cfs 106.254 af
Peak EIev=670.38' Storage=91.431 af Inflow=1,527.46 cfs 178.864 af
Outflow=401.93 cfs 178.864 af
Peak EIev=653.70' Storage=78.625 af Inflow=401.93 cfs 178.864 af
Outflow=81.25 cfs 128.432 af
Peak EIev=632.80' Storage=34.675 af Inflow=358.34 cfs 94.073 af
Outflow=314.64 cfs 93.482 af

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 42
Link A: Outfall A
Link B: Total DA B
Link C: Total DA C
Inflow=339.42 cfs 101.948 af
Primary=339.42 cfs 101.948 af
Inflow=263.38 cfs 120.132 af
Primary=263.38 cfs 120.132 af
Inflow=405.40 cfs 197.323 af
Primary=405.40 cfs 197.323 af
Total Runoff Area = 1,568.600 ac Runoff Volume = 472.965 af Average Runoff Depth = 3.62"
100.00% Pervious = 1,568.600 ac 0.00% Impervious = 0.000 ac

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 43
Summary for Subcatchment Al: Al -A
Runoff = 364.42 cfs @ 12.29 hrs, Volume=
35.975 af, Depth= 4.35"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
99.300 94
99.300 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
20.0
Direct Entry,
Subcatchment Al: Al -A
Hydrograph
4004 l
380- 364.42 cfs
360""
340=' /
320"' a
300 a
280=
260
240'
220=- 1/
200"' 1 ---/
180���
160"'��-_
140
ttii=
1
100
80
60
40=
20=
0
L
1
1
i 1 L 1 L 1
RCCL24-hr $ _
- NRC- F6yr=24hr Rainfall=5.-04'1-
rt
Ikunoff Area=9*.300 ac
Runoff Vorurne=35.975 af -
RinofrDep =4..5" -
r
1
1
4
rt
rt
Tc=/QOmin-
C Nfi94
L 1 L 1
+ + + +
+ + + +
✓ 1
✓ 1
7
L L
10 20 30 40 50 60 70 80 90 100 110 120 130
Time (hours)
140
150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 44
Summary for Subcatchment A2: Al-B
Runoff = 420.37 cfs @ 12.35 hrs, Volume=
46.561 af, Depth= 4.46"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 125.300 95
125.300 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
25.0 Direct Entry,
Subcatchment A2: Al-B
Hydrograph
460
440-
420-
400�Jir
-
380� fi
-
340� - -
320- fi - -
300- -
280 L -
260J z r-
240� z r -
0 220 -
'� 200-
180" -
160�z
140�zT--
120 - -
100= k - -
80� -
40= k--
20 _ j
0-
0
L
420.37 c
L i L i L i 7 i L L L L L
-NRCC24-fir$
L i L
L
L L L L
r r r 1NRCC-_ yr-24hr R;ainfa1F=_5.947 -
Runof#Area-=1r20 66 ac
Runoff Volurhe=4''561-af -
RunoffDepir=4 46"-
• i
r
• 1 r 1 1
7TC=15Umin
i i L i L L
L r L 7 7
1 ' 1
1-1
10 20
r
L i r i T i 7 i 7 T 7 T 7
L
4
30 40 50 60 70 80 90
Time (hours)
100 110 120 130 140 150
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 45
Summary for Subcatchment A3.U: DA Al
Runoff = 102.04 cfs @ 12.43 hrs, Volume=
11.537 af, Depth= 2.57"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
53.900 76
53.900 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
0
LL
Subcatchment A3.U: DA Al
Hydrograph
L L L L
,r---r----r I r I I r r r r r
105J I 102.04 cfs I
1ooJ' / 1�1RCC_24-hrB_
� z 95
90•'=" T
85�/ ---/ I I I I
80 ---
75�// ---/
70� z rrip ---/
65�
)
60� rrr-- -- r r + r r r r r r
551' ; rrir I I I I I V Nr/-6
50J
454" — -
404"/ r
---
35'� --
30
25 T--
20
/---r
4-
NRCC= -Gyr-24hr Rai nfall=5 4" -
r
141
r
Runoff -Area =5 3.SOd ac -
RurnIoff Vorurhe=11.531~af -
15
10
5
0
r --
r r r
Reno# Depth=2 -5Z" -
L L Tc= o in in -
+
r + r T I r 71
L I L
r + r I r r r r r
(
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff
r

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 46
Summary for Subcatchment A4.U: DA A2
Runoff = 87.90 cfs @ 12.32 hrs, Volume=
8.466 af, Depth= 2.75"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
37.000 78
37.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
22.0 Direct Entry,
Subcatchment A4.U: DA A2
Hydrograph
/
95='�T
90'_'
85
80--
75='
70
65
60=-'
55' --
3 50= --
2 45- - —
LL
40
35
30='�
25='�
20='
15=-'
10
5_
r
187.90 cfs
-/
T
/
- — ▪ - 1 4
T
4
rt
rt
Y
T
T
NRCC-241ir 1
+ + + + I 4
NRCC 11 yr--24hr-Rainfa1L=5.114"--
tunoff-Area=3 .fl00 ac -
Runoff Vok me=8.466 af
t r y r 1 rt
RpnaftDep$h=2.7i" -
T
Y
IT
-Tc= 2.0-mi t-
CNr7S
T T
Ti
Ti
1 i i
7
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 47
Summary for Subcatchment B1: B1-A
Runoff = 851.32 cfs @ 12.41 hrs, Volume=
103.601 af, Depth= 4.46"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 278.800 95
278.800 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
Subcatchment B1: B1-A
Hydrograph
950 _
900i- 851.32 cfs
850; IL---/-
800�� ---✓
75O /
700-
650- -
600z�
550
500L-
450="
400E
350E
300
250
200E
150
100E
50-
r
L
L
L
L
L
L
RCCIL24-1 r $ -
NRQC- f0lyr-24hr RainfalF=5.-04" -
RunoflArea=27d.80d ac
Runoff VdFume=10'3.60�'I-af-
▪ R fff Dep=4.-1 6" -
J L
L L
TC= O-0min
—
L L
CNr95
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 48
Summary for Subcatchment B2.U: B2
Runoff = 45.75 cfs @ 12.44 hrs, Volume=
5.192 af, Depth= 2.40"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
26.000 74
26.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
Subcatchment B2.U: B2
Hydrograph
50; -
48 ;' -1 45.75 cf I
46
44" T
42
40"
38
36° T--
34
32 T--
30
H ▪ 28
26 �H
0 24°
LT_ 22 ---
20; /T--
18
16' -
14
12° --
10 --
8- - -
4°�--
2-
1 1
1 L J L 1 1
1 ▪ 1 N-RCC-24 -i r B -
1 7
7 r 7
NRCC-9eyr-24 r- Ra-infalF -5.p4„ -
r
*unoff-Area=2-4.000 c -
i
+
RUnoffAto[dme=5.T92-af -
1
▪ R noff; Depth=2.4014 -
-
+ + + + -
r CN �74
-11
+ 4 1 1 + 1 + + + + 4
+ + + 4
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 49
Summary for Subcatchment B3.U: DA B1
Runoff = 122.30 cfs @ 12.44 hrs, Volume=
13.878 af, Depth= 2.40"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
69.500 74
69.500 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
13°-
12°—
110—
100
90
80�
o
70—
LL 60J
50-
40
30-
20
10-
Subcatchment B3.U: DA B1
Hydrograph
122.30 cfs
--
--
/
N RCC
24-hr B
L
L
L
4
rt
NRCC-10
yr-24hr Rainfall=5.04"
IiunoffArea=B.50d ac
RurnofFVorurhe=13.878 of -
Ri rroff Depth-2. O,i -
Tc=300rnin-
L
L
4
rt
- L
CN,�74
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 50
Summary for Subcatchment C1: Cl-A
Runoff = 1,527.46 cfs @ 12.41 hrs, Volume=
178.864 af, Depth= 4.02"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 533.800 91
533.800 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
30.0 Direct Entry,
1,700-
Subcatchment Cl: Cl-A
Hydrograph
+ H +
J
1 ,600 / 1 1,527.46 cfs
1,500"
1,400' /
1,3007-
1,200L:-
1,100z __
1,000-
900-
800-
700
600J
500-
400-
300=
200-
1 00-
0
i
a
r H H H
L Ji
r NIRCCI24-her B
NRCC-10yr-24hr Rainfall L=54 4" -
Runoff Area= 533.8-0d ac -
+
R-undff V61umle=17'8:864-af -
Rufoff-pepth=4.p2"
J JTc 0.Omin -
CN--91
7
H
J
J
J
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 51
Summary for Subcatchment C2.U: DA C1
Runoff = 405.40 cfs @ 12.84 hrs, Volume=
68.891 af, Depth= 2.40"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Area (ac) CN Description
* 345.000 74
345.000 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
60.0 Direct Entry,
440�
420-
400-
380
360-
340
320
300
280
260
240
220
200
180-
160
140
120
100
80
60
40
20
0
Subcatchment C2.U: DA C1
Hydrograph
+ - - - - + - - - -I- - - - + - - - -I- - - - + - - - -I- - - - + - - - -I- - - - + - - - - + - - - + - - - - + - - - +
r i r i T
r r1
7 7 r 7 r 7
Li Li
Li ii
'
2 RCC_24-qr$-
NRQC--1- yr-24hr Rainf-a1I=5 4" -
RWnof Area=84$-0AA-ac-
Runoff VoFurhe=68.891 of -
1 1
R4no# Dep h-=2;41r -
7 r -1 r1 1 H C Nfi74 -
,- IL
iL L
+--------r--------+-------- -hi
---------11 II-
---+---- II-
---+
4- 1 1- 1 + 1 - 1 1 41 -4
7 i r r r r r
L i L
r
L i L i L L L
+ i i + r i r +
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
• Runoff

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 52
Inflow Area =
Inflow =
Outflow =
Primary =
Summary for Pond Pond Al: Pond Al
99.300 ac, 0.00% Impervious, Inflow Depth = 4.35" for NRCC-10yr-24hr event
364.42 cfs @ 12.29 hrs, Volume= 35.975 af
122.66 cfs @ 12.70 hrs, Volume= 35.975 af, Atten= 66%, Lag= 24.6 min
122.66 cfs @ 12.70 hrs, Volume= 35.975 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 687.06' @ 12.70 hrs Surf.Area= 3.202 ac Storage= 15.321 af
Plug -Flow detention time= 156.4 min calculated for 35.975 af (100% of inflow)
Center -of -Mass det. time= 155.5 min (942.4 - 786.9 )
Volume
Invert Avail.Storage Storage Description
#1 680.00' 44.210 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area
(feet) (acres)
680.00 0.460
682.00 1.540
684.00 2.620
685.00 2.980
690.00 3.520
695.00 4.080
Device Routing
Inc.Store Cum.Store
(acre-feet) (acre-feet)
0.000 0.000
2.000 2.000
4.160 6.160
2.800 8.960
16.250 25.210
19.000 44.210
Invert
Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
680.00' 60.0" Round Culvert
L= 700.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 680.00' / 676.00' S= 0.0057'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
680.00' 24.0" Vert. Orifice/Grate C= 0.600
686.00' 24.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=122.56 cfs @ 12.70 hrs HW=687.06' (Free Discharge)
4-1=Culvert (Passes 122.56 cfs of 192.18 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 37.23 cfs @ 11.85 fps)
3=Sharp-Crested Rectangular Weir(Weir Controls 85.33 cfs @ 3.36 fps)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
400-
360-e-
340
320
300-
280-
260
• 240
i 220 -
200
• 1804-
160
140
120
100
80-
60-
40-
20
0
Elevation (feet)
695/ 1
6947- 11
fi
693�
111
692—
6917/ 1
690--
689— '11
fi
6887- I
687— 1
6867- 11
685— 1
684- /
--
683111
-
7
1
+
1
Pond Pond Al: Pond Al
Hyd rog raph
1
1
Inflow
Y
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 53
Arra-=99.30E pc
P-eak-€le+-=6-87M61--
St-p age=1 &.$21- of - -
1-1
1-1
+ 1 1
+
+
1 J 1 r
10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
Pond Pond Al: Pond Al
Stage-Discharge
r
682. 1
681 J
680
.r.
Sharp -Crested Rectangular Weir
�/ 1
i 1
4-
4-
r
L
r
Culv
11
Ti
i
i
0
50
100
150
Discharge (cfs)
200 250
D Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
1
Pond Pond Al: Pond Al
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 54
3
4
695-
694
693-
692-
691 J
6907-
6897-
688-
0
687J
686J
w
685-
684=
683
682-
681-
680
0
L
1
4
J
I
I I 0.
• L jL
L J + L 1 1
1
L L J + L
• Lr r
+ --+ +----+
L L L L L L
i
I L L
r
71
+ - - - + - - - + + - - - - +
L L L
Custom Stage Data
5 10 15
20 25 30 35 40
Storage (acre-feet)
u Surface
• Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 55
Inflow Area =
Inflow =
Outflow =
Primary =
Summary for Pond Pond A2: Pond A2
125.300 ac, 0.00% Impervious, Inflow Depth = 4.46" for NRCC-10yr-24hr event
420.37 cfs @ 12.35 hrs, Volume= 46.561 af
170.15 cfs @ 12.75 hrs, Volume= 46.561 af, Atten= 60%, Lag= 24.4 min
170.15 cfs @ 12.75 hrs, Volume= 46.561 of
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 658.98' @ 12.75 hrs Surf.Area= 4.301 ac Storage= 17.934 af
Plug -Flow detention time= 124.8 min calculated for 46.561 af (100% of inflow)
Center -of -Mass det. time= 124.7 min (911.0 - 786.3 )
Volume
Invert Avail.Storage Storage Description
#1 650.00' 74.970 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area
(feet) (acres)
650.00 0.030
652.00 0.650
654.00 1.550
656.00 2.640
658.00 4.100
660.00 4.510
670.00 6.000
Device Routing
Inc.Store Cum.Store
(acre-feet) (acre-feet)
0.000 0.000
0.680 0.680
2.200 2.880
4.190 7.070
6.740 13.810
8.610 22.420
52.550 74.970
Invert
Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
650.00' 60.0" Round Culvert
L= 400.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 650.00' / 644.00' S= 0.0150'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
650.00' 24.0" Vert. Orifice/Grate C= 0.600
658.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=169.84 cfs @ 12.75 hrs HW=658.98' (Free Discharge)
4-1=Culvert (Passes 169.84 cfs of 240.68 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 42.73 cfs @ 13.60 fps)
3=Sharp-Crested Rectangular Weir(Weir Controls 127.11 cfs @ 3.24 fps)

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 56
460
440='z
420
400
380='
360"-
340
320
300-=-
280
260
240-
220J
LL 200=
180
160
140=
120=
100
80-
60
40-
20-
0
Elevation (feet)
Pond Pond A2: Pond A2
Hyd rog raph
4
420.37 cfs
70.15 cfs
TI
f I T
1nflpw ikregi=1 5.400 c
4 Peak TE1 aw=6158 V
✓ ▪ rS Qrage#17.Q14Taf
T----
4
4-4-
1 I r 1 I r
II I I L I T
r 1 I r I r T I r 1
T
T
+ + I + I H + I + + I +
1- -1 I -L I L- -L 4- -1 I 4-
TI I L T
TI L T
T
r
0 10 20 30 40 50 60 70 80 90
Time (hours)
670/
669J
668'"
667J
666'"
665J
664'"
663J
662-
661"z
660-
659J
658'
657=
100
110 120
Pond Pond A2: Pond A2
Stage -Discharge
L L L L
L
656' — -
655_ _ _
654=
653=
652'-
651_ C
650
r
L
L
L Sharp -Crested Rectangular Weir 1-1
r
L
130
140
150
+ + +
✓ + r
r r
✓ 1 r
1 r
r
L r
0
100
150 200 250
Discharge (cfs)
300
350
U Inflow
• Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
670
669
668J
667
666
665
664
663
662
661H�
660H
659
658-
657J
656
655
654=
653-
652=
651 Custom
1
Pond Pond A2: Pond A2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3 4
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 57
5
6
0 5 10 15 20 25
30 35 40 45
Storage (acre-feet)
50 55
60
65
70
Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 58
Summary for Pond Pond B1: Pond B2
Inflow Area = 278.800 ac, 0.00% Impervious, Inflow Depth = 4.46" for NRCC-10yr-24hr event
Inflow = 851.32 cfs @ 12.41 hrs, Volume= 103.601 af
Outflow = 291.40 cfs @ 12.95 hrs, Volume= 103.601 af, Atten= 66%, Lag= 32.6 min
Primary = 291.40 cfs @ 12.95 hrs, Volume= 103.601 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 662.00' @ 12.95 hrs Surf.Area= 7.580 ac Storage= 47.151 af
Plug -Flow detention time= 273.2 min calculated for 103.601 of (100% of inflow)
Center -of -Mass det. time= 272.3 min (1,063.2 - 790.9 )
Volume Invert Avail.Storage Storage Description
#1 650.00' 290.310 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
650.00 0.750 0.000 0.000
652.00 1.630 2.380 2.380
654.00 2.650 4.280 6.660
656.00 3.770 6.420 13.080
658.00 5.000 8.770 21.850
660.00 6.360 11.360 33.210
662.00 7.580 13.940 47.150
664.00 9.380 16.960 64.110
666.00 11.070 20.450 84.560
668.00 13.160 24.230 108.790
670.00 13.810 26.970 135.760
680.00 17.100 154.550 290.310
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
650.00' 60.0" Round Culvert
L= 750.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 650.00' / 640.00' S= 0.0133'/' Cc= 0.900
n= 0.013, Flow Area= 19.63 sf
650.00' 24.0" Vert. Orifice/Grate C= 0.600
660.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=291.39 cfs @ 12.95 hrs HW=662.00' (Free Discharge)
4-1=Culvert (Inlet Controls 291.39 cfs @ 14.84 fps)
AL2=Orifice/Grate (Passes < 50.17 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 369.90 cfs potential flow)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
950-
900-
850
800
750
700
650-
600J
w 550'
• 500-
0 450�
• 400-
350-
300-
Elevation (feet)
250=
200-
150-
100
50=
0
0 10
7
291.40 cfs
680/
678� t
676�
674—
6727-
670—
668=
6667-
664—
6627-
660=-
Pond Pond B1: Pond B2
Hyd rog raph
i
r
T
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 59
r
r
Inflow -kre =278:G-O0 ae
Peak Elev=-662.1 O-'--
Storage=47.151 af
20 30 40 50 60 70 80 90 100 110 120 130 140 150
Time (hours)
i
r
L
L
-
658
656-
654.
652� t
650
0
i
Pond Pond B1: Pond B2
Stage -Discharge
Sharp -Crested Rectangular Weir
i
r
tl
L LI
- ----
J
100 150 200 250 300 350 400 450
Discharge (cfs)
D Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
680:
678�
6761:'
674-
672J
6707-
6687-
6667:'
o -
664J
. 662J
660-
658:
656=
654
652
650
0 1 2
+I
II
Pond Pond B1: Pond B2
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 60
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
'' '1'I' "'I"'I"'II' 'r'I"'I"11"'A"'I1"'I1..I'1'
++---I+---I+
IL I 1I I I I I L IL
r 1 1 1 4
1 I Ir
It + + + ++ I+
I 1 I II
IL
4
11- r1 Ir Ir
+ 1 I 1 I+11
IL
+I III 111
J 1 LL IL IL
1
I
L 1
I II
L LL u
0 20 40 60 80 100 120 140 160 180 200
Storage (acre-feet)
220
L 1
240 260
280
ti
1 L L
• Surface`
• Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 61
Summary for Pond Pond B2: Pond B2
Inflow Area = 304.800 ac, 0.00% Impervious, Inflow Depth = 4.28" for NRCC-10yr-24hr event
Inflow = 318.02 cfs @ 12.72 hrs, Volume= 108.793 af
Outflow = 242.91 cfs @ 13.59 hrs, Volume= 106.254 af, Atten= 24%, Lag= 52.5 min
Primary = 242.91 cfs @ 13.59 hrs, Volume= 106.254 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 614.00' Surf.Area= 4.900 ac Storage= 28.400 af
Peak Elev= 619.49' @ 13.59 hrs Surf.Area= 5.907 ac Storage= 58.091 af (29.691 af above start)
Plug -Flow detention time= 1,343.4 min calculated for 77.828 af (72% of inflow)
Center -of -Mass det. time= 778.3 min (1,831.8 - 1,053.5 )
Volume Invert Avail.Storage Storage Description
#1 608.00' 61.100 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
608.00 4.500 0.000 0.000
610.00 4.700 9.200 9.200
612.00 4.800 9.500 18.700
614.00 4.900 9.700 28.400
620.00 6.000 32.700 61.100
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
609.00' 66.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 609.00' / 608.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 23.76 sf
614.00' 8.0" Vert. Orifice/Grate C= 0.600
618.00' 40.0' long Sharp -Crested Rectangular Weir O End Contraction(s)
Primary OutFlow Max=242.60 cfs @ 13.59 hrs HW=619.49' (Free Discharge)
4-1=Culvert (Passes 242.60 cfs of 318.33 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 3.82 cfs @ 10.94 fps)
3=Sharp-Crested Rectangular Weir(Weir Controls 238.78 cfs @ 4.00 fps)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
340J
320-
300-
280
260-
240-
220-
w 200�
3 180-
° 160=
LL =
140-
120-
100-
80-
60?
40-
20-
0
617
616
w 615
g 614
>
w 613
w
612
611
610
608
Pond Pond B2: Pond B2
Hyd rog raph
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 62
318.02 cfs
242.91 cfs
Inflow ATea=34.80E c -
Peak rE-1ev= Saa 4a'
4
= _St6ratge=:`,58.091 +af
0 10 20 30 40
-r
+
50 60 70 80 90 100 110 120 130 140 150
Time (hours)
Pond Pond B2: Pond B2
Stage -Discharge
Sharp -Crested RectangiEM
1
0
Orifice/rate
r
+
1
+
50
100
150 200
Discharge (cfs)
250
300
• Inflow
❑ Primary
❑ Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
620
619:
618-
617:-
616-
615:-
614-
613:
612-
609-
608
1
Custom Stage Data
Pond Pond B2: Pond B2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3 4
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 63
5
0 5 10 15 20 25 30 35
Storage (acre-feet)
40
45
50
55
60
6
D Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 64
Summary for Pond Pond Cl: Pond C1
Inflow Area = 533.800 ac, 0.00% Impervious, Inflow Depth = 4.02" for NRCC-10yr-24hr event
Inflow = 1,527.46 cfs @ 12.41 hrs, Volume= 178.864 of
Outflow = 401.93 cfs @ 13.10 hrs, Volume= 178.864 af, Atten= 74%, Lag= 41.3 min
Primary = 401.93 cfs @ 13.10 hrs, Volume= 178.864 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Peak Elev= 670.38' @ 13.10 hrs Surf.Area= 12.191 ac Storage= 91.431 af
Plug -Flow detention time= 485.4 min calculated for 178.864 af (100% of inflow)
Center -of -Mass det. time= 484.7 min (1,294.0 - 809.4 )
Volume Invert Avail.Storage Storage Description
#1 658.00' 460.200 af Custom Stage Data (Prismaticpsted below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
658.00 0.760 0.000 0.000
660.00 2.920 3.680 3.680
662.00 5.960 8.880 12.560
664.00 8.150 14.110 26.670
666.00 9.340 17.490 44.160
668.00 10.650 19.990 64.150
670.00 12.000 22.650 86.800
672.00 13.000 25.000 111.800
674.00 14.200 27.200 139.000
676.00 16.300 30.500 169.500
678.00 17.500 33.800 203.300
680.00 19.900 37.400 240.700
690.00 24.000 219.500 460.200
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
658.00' 72.0" Round Culvert
L= 400.0' RCP, groove end w/headwall, Ke= 0.200
Inlet / Outlet Invert= 658.00' / 657.00' S= 0.0025'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
658.00' 24.0" Vert. Orifice/Grate C= 0.600
668.00' 60.0' long Sharp -Crested Rectangular Weir End Contraction(s)
Primary OutFlow Max=401.95 cfs @ 13.10 hrs HW=670.38' (Free Discharge)
4-1=Culvert (Barrel Controls 401.95 cfs @ 14.22 fps)
AL2=Orifice/Grate (Passes < 51.03 cfs potential flow)
3=Sharp-Crested Rectangular Weir(Passes < 715.88 cfs potential flow)

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 65
Pond Pond Cl: Pond C1
Hyd rog raph
1,700 ' � 1,527.461 cfs
1,6007'
1,500�
1,4001;"�
,r
1,3007'/ '
1,2007
1,1007'
1,0007-
9007"
8007" it
7007" A
r--
600-
5007'
4007'
3007'
2007'
100�
0
690-
688J
686J
6847-
682J
680-:'
678-
w
676-
0 674�
> 6727-
w 670�
668J
666J
664=
662=
660:
658
01.93 cfs
4
r
L
1-1
1
4
L
rift w rea=5 3,a00- c
Peak EIev=6'7O..8'
S oraige91 43-ifaf
L 1 �
1
✓
1-1
— — — y
✓ r
r
r
✓ -1
r T r
10
20
30
40
50 60
70 80
Time (hours)
90 100 110 120 130 140 150
Pond Pond Cl: Pond C1
Stage -Discharge
Sharp -Crested Rectangular Weir
r
4-1
1-1
i
i
it
i
i
0
100
200 300 400 500 600 700
Discharge (cfs)
• Inflow
❑ Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
Pond Pond Cl: Pond C1
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 66
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
690
688
686-
684-
682�
680�
678�
676�
674-
672�
670-
668-
666�
664_
662-
660
658 .
11
1
4
Custom Stag
1 1 r
1I--+--r----1--rlrI--R--r
- +-+----+I--+--+-I-I--+--+I--+
- 1' - - - I - - 1 - - + - - I - I - I - - 4
-1' _ ---I--JI-_ 1--�
1
- 1
11
1I
44
44
u
u
r
0
50 100 150 200 250 300 350 400 450
Storage (acre-feet)
• Surface`
• Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 67
Summary for Pond Pond C2: Pond C2
Inflow Area = 533.800 ac, 0.00% Impervious, Inflow Depth = 4.02" for NRCC-10yr-24hr event
Inflow = 401.93 cfs @ 13.10 hrs, Volume= 178.864 af
Outflow = 81.25 cfs @ 16.24 hrs, Volume= 128.432 af, Atten= 80%, Lag= 188.6 min
Primary = 81.25 cfs @ 16.24 hrs, Volume= 128.432 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 630.00' Surf.Area= 0.000 ac Storage= 0.000 af
Peak Elev= 653.70' @ 16.24 hrs Surf.Area= 9.344 ac Storage= 78.625 af
Plug -Flow detention time= 1,391.0 min calculated for 128.432 af (72% of inflow)
Center -of -Mass det. time= 1,057.7 min (2,351.7 - 1,294.0 )
Volume Invert Avail.Storage Storage Description
#1 644.00' 190.900 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
644.00 6.000 0.000 0.000
646.00 7.000 13.000 13.000
648.00 8.000 15.000 28.000
650.00 8.900 16.900 44.900
655.00 9.500 46.000 90.900
660.00 10.000 48.750 139.650
665.00 10.500 51.250 190.900
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
644.00' 72.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 644.00' / 643.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
650.00' 10.0" Vert. Orifice/Grate C= 0.600
653.00' 40.0' long Sharp -Crested RectangularWeir° End Contraction(s)
Primary OutFlow Max=80.88 cfs @ 16.24 hrs HW=653.70' (Free Discharge)
4-1=Culvert (Passes 80.88 cfs of 352.31 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 4.76 cfs @ 8.72 fps)
3=Sharp-Crested Rectangular Weir(Weir Controls 76.13 cfs @ 2.73 fps)

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 68
440y'
420
400
380�
360
340
320
300
280
• 260
- 240"
220
L—°° 200J
180
160
140
120
100
80
60-
40
20'
0
w
0
w
w
Pond Pond C2: Pond C2
Hyd rog raph
401.93 cfs
i
rt i
inflpw 4k-e4=533.8-O0 ac
Y
r rt
akc E1ev=653.- O' -
L
Stora e,7&625taf--
i
i
+
1 1I
1 1
81.25cfs +--
•I IL
0 10 20 30 40 50 60 70 80 90
Time (hours)
664
663=
100
110 120
Pond Pond C2: Pond C2
Stage -Discharge
130
140
150
662/ )
661'
660
659=- '+
658/
657�
656'
655=
654/
653J
652-
651 -
650-
i
7
T
Sharp-Crested Rectangular
7
i
r
1
rr
r
r
4
4
4
649
648
647 A
645
644 ,,
0 50 100
i
i
i
i
,, ,.
150 200 250 300 350 400 450 500
Discharge (cfs)
4
4
1
550
U Inflow
• Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
665-
664
663
662
661-
660'
659
658
657
656
655�
654
653='
652=
651-
650
z 649 '
648=
647-
646
645
644
1
2
Pond Pond C2: Pond C2
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
3 4 5 6 7
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 69
8
9
10
++-+---It--+--+1---+ 1 1 t ++ ++
4-11 4- 1
TI T 1
r11 1i T 11 T 1 1 r 1
--+I----+-I--- 1 1 1 - - --&-- --+I1
1 1 I 1 J 1 L I L L_ J___ LL-- 1
r 1 1 rr-r---rr
+--+I---+-+-1---+-I--I---++
1--11---1-J-1---L-I
Ti1T
4 - - 1 I
T1
L
1
T r
1 11 L uL ___1 1
t _J
11 r rr
-
--rr
It + +1 + I + ++ ++
L L_ J LL 1 JI 1 I
1it 4 4 4 41
Ti
11 r T
4-
1
1 T I
1 J 1 L I
t1r+y-1---r
11 4 11 1
II I II
11 - T T 1I T
L L J 1L 1 41 1
r r + + +1
4
I I
T
r--
1
11 tr+---r+-+
+
1
4
-r
1
r
1
L
+
Custom Stage Data
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190
Storage (acre-feet)
• Surface
• Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 70
Summary for Pond PondA3: Pond A3
Inflow Area = 278.500 ac, 0.00% Impervious, Inflow Depth = 4.05" for NRCC-10yr-24hr event
Inflow = 358.34 cfs @ 12.68 hrs, Volume= 94.073 af
Outflow = 314.64 cfs @ 12.89 hrs, Volume= 93.482 af, Atten= 12%, Lag= 12.4 min
Primary = 314.64 cfs @ 12.89 hrs, Volume= 93.482 af
Routing by Stor-Ind method, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
Starting Elev= 628.00' Surf.Area= 3.200 ac Storage= 17.800 af
Peak Elev= 632.80' @ 12.89 hrs Surf.Area= 3.780 ac Storage= 34.675 af (16.875 af above start)
Plug -Flow detention time= 586.6 min calculated for 75.657 af (80% of inflow)
Center -of -Mass det. time= 374.0 min (1,289.9 - 915.9 )
Volume Invert Avail.Storage Storage Description
#1 622.00' 65.750 af Custom Stage Data (Prismatic)Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
622.00 2.800 0.000 0.000
626.00 3.000 11.600 11.600
628.00 3.200 6.200 17.800
630.00 3.500 6.700 24.500
635.00 4.000 18.750 43.250
640.00 5.000 22.500 65.750
Device Routing Invert Outlet Devices
#1 Primary
#2 Device 1
#3 Device 1
622.00' 72.0" Round Culvert
L= 100.0' RCP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 622.00' / 621.00' S= 0.0100'/' Cc= 0.900
n= 0.013, Flow Area= 28.27 sf
628.00' 7.0" Vert. Orifice/Grate C= 0.600
631.00' 40.0' long Sharp -Crested Rectangular Weir End Contraction(s)
Primary OutFlow Max=314.23 cfs @ 12.89 hrs HW=632.79' (Free Discharge)
4-1=Culvert (Passes 314.23 cfs of 380.07 cfs potential flow)
AL2=Orifice/Grate (Orifice Controls 2.73 cfs @ 10.22 fps)
3=Sharp-Crested Rectangular Weir(Weir Controls 311.50 cfs @ 4.38 fps)

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
0
LL
Elevation (feet)
Pond PondA3: Pond A3
Hyd rog raph
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 71
400
380�
360J
340
320�
300-
280J
260
240�
220-
200J
180�
160-
140
120=
100-
80
40=
20
0
Y
358.34 cfs
14.64 cfs
L 1
L
T T
L L
L
L 1
L L
1
1
t
IT
inflpw Are =27&50 c
L P- aktE1ev=63--,$a'--
rt Storag e#34.-67-5 of--
L L
L
L 1
L
T T T
L L
L
L L
L
L
0 10 20 30 40 50 60 70 80 90
Time (hours)
100
110 120
Pond PondA3: Pond A3
Stage -Discharge
130
140
150
6404 _
639/
638/
637� z
6361_-/
635'; '
-
634
633-
632�
631:
630
629
628=
627=
%J
626
625
624
623
622
T
t
+
T
t
Sharp -Crested Rectangular Weir
T
t
+
T
+
H
H
0
50
100
150
200
250 300
Discharge (cfs)
350
400
450
500
U Inflow
• Primary
• Primary`

ProposedConditions
Prepared by HDR, Inc
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC
Elevation (feet)
640J
639-
638J
637
636
635
634-
633-
632-
631-
630-
629=
628J
627
626J
625-
624-
623=
622
1
Pond PondA3: Pond A3
Stage -Area -Storage
Surface/Horizontal/Wetted Area (acres)
2 3
Custom Stage Data
i
i
i
0 5 10 15 20 25 30 35 40
Storage (acre-feet)
45
50
NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Printed 10/20/2021
Page 72
55
4
60
65
5
D Surface
❑ Storage

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 73
Inflow Area =
Inflow =
Primary =
315.500 ac,
339.42 cfs @
339.42 cfs @
Primary outflow = Inflow, Time
380J
360-
340-
320,-
300-
280-
260-
240-
220='
200 "
180�
160-
140-
120=
100
80-
60
40,
20-
0
Summary for Link A: Outfall A
0.00% Impervious, Inflow Depth > 3.88" for NRCC-10yr-24hr event
12.86 hrs, Volume= 101.948 of
12.86 hrs, Volume= 101.948 af, Atten= 0%, Lag= 0.0 min
Span= 0.00-150.00 hrs, dt= 0.05 hrs
Link A: Outfall A
Hyd rog raph
T
T
339.42 cfs
39.42 cfs
10
20
T
Inflow ATe4=3-15.4O0 Tac -
30 40 50
60 70 80 90 100 110 120 130 140 150
Time (hours)
C Inflow
❑ Primary

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 74
Summary for Link B: Total DA B
Inflow Area = 374.300 ac, 0.00% Impervious, Inflow Depth > 3.85" for NRCC-10yr-24hr event
Inflow = 263.38 cfs @ 13.57 hrs, Volume= 120.132 af
Primary = 263.38 cfs @ 13.57 hrs, Volume= 120.132 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
280J
260::
2407:-
220:
200:
180:-
u 160J
0 140-1'
1207.
100:-
40
20=
0
263.38 cfs
263.38 cf
10 20 30 40
Link B: Total DA B
Hyd rog raph
1
jnflpw*e-314 1Q0
T T + T
L 1 L ..
50 60 70 80 90
Time (hours)
1-1
100 110 120 130 140 150
C Inflow
❑ Primary

ProposedConditions NRCC 24-hr B NRCC-10yr-24hr Rainfall=5.04"
Prepared by HDR, Inc Printed 10/20/2021
HydroCAD® 10.00-25 s/n 07102 © 2019 HydroCAD Software Solutions LLC Page 75
Summary for Link C: Total DA C
Inflow Area = 878.800 ac, 0.00% Impervious, Inflow Depth > 2.69" for NRCC-10yr-24hr event
Inflow = 405.40 cfs @ 12.84 hrs, Volume= 197.323 af
Primary = 405.40 cfs @ 12.84 hrs, Volume= 197.323 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-150.00 hrs, dt= 0.05 hrs
440
4201-
400
380
360
340
320
300�
2804
260
240
220-
200=
180
160
140
120
100=
80J
60
40
20
0
Link C: Total DA C
Hyd rog raph
✓ -1
Y
rt
1 4
405.40 cfs
05.40 cfs
LI 4 1 4
✓ 1 1 T
4
r
1
r
Inflow =8-78: Oo- ae--
L
✓ 4 1 7 1 r 4 1 r 4 1 r
4 4 4 4 4 + 4 +
✓ T T I—T r T T
L L L L L L L L
4 4 4 H 4 + 4 +
r T - 1 L I I I r
r---y t 1 II—-'I
t---y 1 +
L - 1 4 1 I 4 L - 1 L
r 7 1 Y 1 r Y r 7 1 T
10
20 30 40 50
60 70 80 90 100
Time (hours)
110 120
130
140
150
C Inflow
❑ Primary