SW6210602_Stormwater Report_20211006

Prepared for:
LITTLE CROSS, LLC
8625 Mt. Pleasant Church Road
Angier, NC 27592
919.422.7066
StIormwater Erosion
Control Narrative
Kathryn's Retreat Subdivision
Phase 4
Harnett County, NC
Town of Angier
Apri 19, 2021
Curr
ENGINEERING
Prepared by:
Andy Petty, PE
The Curry Engineering Group, PLLC
PO Box 2018
205 S. Fuquay Ave.
Fuquay-Varina, NC 27526
[phone]
� rt
36823
2021.04.08 09.37.17 -
04'00'

Curr
ENGINEERING
TABLE OF CONTENTS
NARRATIVES
Site Location and Description
Project Development
Erosion Control
Stormwater Management
Storm Sewer Hydraulic Gradeline Analysis
Storm Sewer Gutter Spread Analysis
SUPPORT DOCUMENTS
USGS Topography Map
FEMA Floodplain Map
NRCS Soils Information
Rainfall Data
Stream Classification
CALCULATIONS & ANALYSIS
Stormwater Management Calculations
Storm Sewer Calculations
Gutter Spread Calculations
Outlet Protection Calculations
Sediment Basin Calculations
Diversion Ditch Calculations
T [phone] 205 S. Fuquay Avenue
F [phone] Fuquay-Varina, NC 27526
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NARRATIVES
Site Location & Description
Little Cross, LLC, plans to develop approximately 13.9 acres of vacant property off Campbell Road in
Angier, NC. The property is bordered by vacant property to the west, the Town of Angier sewage
treatment plant to the south, and Campbell Road to the east and north.
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Figure 1 - Vicinity Map - Courtesy of Harnett County GIS 2018
The property historically has been uses for farming and is currently vacant. About half the site is
cleared and half is wooded. There is a jurisdictional pond located near the middle of the site with
jurisdictional stream that runs from the base of the pond to Black River which bi-sects the south west
corner of the proeprty. Since this stream is in the Cape Fear River Basin, there are no riparian buffers
required however neither feature will be impacted. Wetlands also exist on the property throughout the
property. For Phase 4, there are no impacts anticipated to wetlands.
3

Project Development
The developer plans to develop the property such that a total of 27 lots can be constructed in this
phase. The lots will be all single family detached dwelling units. The property is zoned to R6. The
developer plans to mass grade the property and as a result, a larger disturbance is proposed than
what would be needed for infrastructure only. Public utilities will be required for the subdivision.
The nearest point of connection for potable water is an existing 6" public water main within the
Campbell Road right of way. The nearest public sanitary sewer is connection is an existing 12" sewer
outfall along the western side of the property that drains to the Town of Angier sewer treatement
plant.
Erosion Control
The purpose of this project is to clear and grub and construct infrastructure and lot grading for the
27-lot phase of this residential subdivision. The property is privately owned. See owner information on
existing conditions plan. The site is currently undeveloped.
Approximately 8 acres will be disturbed during construction. The maximum fill will be approx. 2 feet.
This project will involve removal of topsoil to create residential roadway and infrastructure as well as
mass grading of lots. An underground storm drainage system will be installed to convey stormwater
to permanent stormwater management areas.
The project is scheduled to begin construction in late spring 2021 with project completion and final
stabilization by fall of 2021. The erosion and sediment control program for this project will include the
installation of a suitable construction entrance, temporary silt fencing, silt fence outlets, diversion
ditches, inlet protection measures and sediment basins.
The soils at this site are predominately loamy sands. Soils are mostly well drained with Ksat ranges
from moderately low to high. Slopes are largely between 2 to 6%, but up to 10% in some cases. The
soils are classified within hydrologic group B/C.
Soils information has been obtained through the USDA & NRCS website:
http://websoilsurvey.nres.usda.gov/app/ for Harnett County.
Stormwater Management
The site drains to Black River within the Cape Fear River Basin. The stream index classification is
#18-68-12-1 and is designated as "C; Sw". This site is located within a Phase II regulated area of the
Cape Fear River basin of North Carolina. Phase II regulations require that all impervious surfaces
captured must be treated for 85% total suspended solids (TSS) and the volume of runoff from the first
inch of rainfall be treated and released over two to five days. An additional requirement for detention
of the 2-yr and 10-yr storm events per the Town of Angier Stormwater ordinance must also be met.
4

To treat 85% TSS and control the pre -post attenuation, a wet detention basin is being utilized to
capture on -site stormwater runoff. At this time, the Town of Angier, per their Phase II permit does not
require treatment or an off -set payment for nutrient removal (nitrogen or phosphorus). However, per
NCDENR Water Quality, a wet detention basin will provide a 25% reduction in nitrogen and a 40%
reduction in phosphorus.
This project is considered a high density (greater than 24% impervious) project once fully built out. The
following is a brief summary of the stormwater requirements for this site from the Town of Fuquay-
Varina Stormwater ordinance.
Control and treat the difference in stormwater runoff volume leaving the project site for the
one inch (1 ") rainfall event. This volume shall draw down between 2-5 days.
Must be designed per NCDENR standards to meet 85% Total Suspended Solids (TSS) removal.
Peak flow attenuation for the 1 yr, 2 yr and 10 yr 24-hour rainfall events
The project includes mass grading the site, however, the intent is to mimic the existing drainage
patterns in the post development state without significant diversions. The site drains toward Black
River as shown on SW-01.
In order to accomplish minimize impacts to natural drainage basins; a wet detention pond is located
such that it drains the entire roadway infrastructure and all single family lots. A series of catch basins
and yard inlets are provided to capture the runoff from the lots and roadways. The results of the pre -
post analysis provide compliance with the pre -post stormwater controls cumulatively for the site. The
pre -development conditions were modeled with hydrologic soils type "B" in fair conditions as the
surrounding areas have been used for farming with sparse ground cover.
A season high water table investigation has not yet been conducted however the wet detention facility
has been designed with a clay liner to limit both ground water and reduced permanent pool volume.
The wet detention facilities have been modeled using Hydraflow Hydrographs by AutoDesk. The SCS
method was utilized for determining pre/post flow rates.
Water Quality - Permanent Pool Requirement
Permanent Pool
Permanent Pool
Water Quality
Water Quality
SCM Number
Area Required (SF)
Area Provided (SF)
Volume Required
Volume Required
(C F)
(C F)
3
4,854
6,536
11,194
12,793
5

Water Quantity Summary Table
Pre -Development
Post -Development Peak
Net Change
Net Change
Storm Event
Peak Flow
Flow w/SCM
(cfs)
(%)
(cfs)
(cfs)
2 yr
31.98
20.42
-11.56
-36%
10 yr
95.52
69.78
-25.74
-27%
25 yr
141.74
177.06
35.32
25%
100 yr
227.52
355.86
128.34
56%

Storm Sewer Hydraulic Grade Iine Analysis
The project will require the use of several curb inlets & yard inlets to capture stormwater runoff.
Standard NCDOT grated type catch basins are being utilized within the subdivision and right of way
street improvements. The storm drainage system for this project has been designed with the following
criteria:
• Class III RCP with 15-in minimum pipe diameter.
• Start the HGL analysis at 80% full of the outlet pipe
• Maintain 10 yr. HGL inside system
• Minimum slope of 0.5%.
• Minimum velocity of 2 fps and max velocity of 10 fps.
• Minimum Cover of 2-ft (top of subgrade to crown).
Each inlet has a delineated drainage basin composite C value for land use and a minimum Tc of five (5)
minutes for the enclosed pipe system sizing. The rational method was utilized for calculating peak
flow.
The hydraulic grade line for the storm drainage system was calculated using Hydraflow Storm Sewers
by Autodesk. The analysis included checking the system for inlet control. Refer to the calculations
section for the Hydraflow output calculations.
Storm Sewer Gutter Spread Analysis
In addition to an HGL anlaysis the storm sewer system in the residential roadways were analyzed for
gutter spread. The gutter spread for the storm drainage system has been designed with the following
criteria:
• Max gutter spread within roadway is 8 feet during the 4 in/hr event with the exception of
cul-de-sac catch basins, yard inlets and inlets inside parking areas.
• Mannings "n" of the gutter is 0.013.
• Cross slope of road is 2%
• Longitudinal slope of road as designed.
Each inlet has a delineated drainage basin, composite C value for land use and a minimum Tc of five
(5) minutes. The rational method was utilized for calculating peak flow.
The gutter spread analysis for the storm drainage system was calculated using Hydraflow Storm
Sewers by Autodesk. The analysis included checking the system for inlet control. Refer to the
calculations section for the Hydraflow output calculations.
7

SUPPORT DOCUMENTS
USGS 7.5 Minute Map
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PROPERTY BOUNDARY
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T [phone] 205 S. Fuquay Avenue
F [phone] FuquayWanna, NC 27526
NC LIC. NO. P-0799
KATHRYNS PLACE SUBDIVISION
USGS 7.5 MINUTE MAP

SUPPORT DOCUMENTS
FEMA Flood Map
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FEMA MAP
ENGINEERING NC LIC. NO. P-0799

SUPPORT DOCUMENTS
USDA Soils Survey
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Custom Soil Resource Report
Soil Map
PROPERTY BOUNDARY
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SUPPORT DOCUMENTS
Rainfall Data
N
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NOAA Atlas 14, Volume 2, Version 3
Location name: Erwin, North Carolina, USA* Mt
Latitude: 35.3247°, Longitude:-78.6880
Elevation: 148.53 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 I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hourp
Duration
Average recurrence interval (years)
1
2
5
10
25
50
1 100
100
200
500
1000
5-min
5.24
(4.79-5.77) 11
6.16
(5.64-6.78)
7.13
7.91
8.81
1 (8.00-9.66)
9.49
(8.59-10.4)
10.1
1 (9.11-11.1)
10.7
1 (9.60-11.7)
11.4
1 (10.2-12.5)
12.1
1 (10.6-13.2)
4.18
4.93
5.71
6.33
7.02
7.55
8.05
8.50
9.05
9.49
10-min
(3.82-4.61)
(4.51-5.42)
1 (5.77-6.95) 11
(6.37-7.70)
1 (6.84-8.27)
1 (7.24-8.81)
1 (7.61-9.31)
1 (8.03-9.91)
1 (8.35-10.4)
3.49
4.13
4.81
5.34
5.93
6.38
6.78
7.15
7.60
7.94
15-min
(3.18-3.84)
1 (4.40-5.29) 11
(4.86-5.86) 11
(5.39-6.50)
1 (5.77-6.98)
1 (6.10-7.42)
1 (6.40-7.83)
1 (6.74-8.32)
1 (6.98-8.71)
2.39
2.85
3.42
3.87
4.39
4.80
5.20
5.57
6.05
6.43
30-min
(2.18-2.63) 11
(2.61-3.14) 11
(3.12-3.76) 11
(3.53-4.25) 11
(3.99-4.82)
1 (4.35-5.26)
1 (4.67-5.68)
1 (4.98-6.09)
1 (5.36-6.62)
1 (5.65-7.05)
1.49
1.79
2.19
2.52
2.93
3.25
3.58
3.90
4.34
4.69
60-min
(1.36-1.64) 1
1 (2.00-2.41)
1 (2.66-3.21)
1 (2.95-3.56)
1 (3.22-3.91)
1 (3.49-4.27)
1 (3.84-4.75)
1 (4.13-5.15)
0.874
1.06
1.32
1.53
1.81
2.05
2.28
2.53
2.86
3.14
2-hr
(0.790-0.978)
(0.957-1.18) 1
1 (1.62-2.02)
(1.82-2.28)
1 (2.02-2.54)
1 (2.22-2.81)
1 (2.49-3.18)
1 (2.71-3.50)
0.618
0.748
0.934
1.10
1.31
1.50
1.69
1.89
2.18
2.42
3-hr
(0.560-0.693)
(0.677-0.836)
(0.844-1.05)
(0.988-1.22) 11
(1.18-1.46)
1 (1.33-1.67)
1 (1.49-1.88)
1 (1.66-2.10)
1 (1.88-2.42)
1 (2.07-2.70)
0.370
0.447
0.560
0.658
0.790
0.904
1.02
1.15
1.33
1.49
6-hr
(0.337-0.412)
(0.407-0.497)
(0.508-0.621)
(0.595-0.729)
(0.709-0.874)
(0.806-0.999)
(0.904-1.13)
1 (1.01-1.27)
1 (1.15-1.47)
1 (1.27-1.64)
0.216
0.261
0.329
0.389
0.470
0.541
0.616
0.698
F 0.815
F 0.918
12-hr
(0.196-0.241)
(0.237-0.291)
(0.297-0.367)
(0.350-0.432)
(0.420-0.522)
(0.479-0.599)
(0.540-0.681)
(0.605-0.771)
(0.695-0.900)
(0.772-1.01)
0.127
0.154
0.198
0.233
0.281
0.322
0.364
0.408
0.471
0.523
24-hr
(0.116-0.140)
(0.141-0.170)
(0.180-0.217)
(0.211-0.255)
(0.254-0.309)
(0.290-0.353)
(0.326-0.399)
(0.365-0.449)
(0.418-0.520)
(0.462-0.577)
0.074
0.090
0.114
0.134
0.161
0.183
0.207
0.232
0.267
0.295
2-day
(0.068-0.081)
(0.082-0.098)
(0.104-0.125)
(0.122-0.146)
(0.146-0.176)
(0.165-0.200)
(0.186-0.226)
(0.207-0.254)
(0.237-0.293)
(0.260-0.325)
0.053
0.064
0.080
0.094
0.112
0.128
0.144
0.160
0.184
0.203
3-day
(0.049-0.057)
(0.059-0.069)
(0.074-0.087)
(0.086-0.102)
(0.102-0.122)
(0.116-0.139)
(0.130-0.156)
(0.144-0.175)
(0.164-0.201)
(0.180-0.222)
0.042
0.051
0.064
0.074
0.088
0.100
0.112
0.125
0.142
0.157
4-day
(0.039-0.045)
(0.047-0.055)
(0.058-0.069)
(0.068-0.080)
(0.081-0.095)
(0.091-0.108)
(0.101-0.121)
(0.112-0.135)
(0.128-0.155)
(0.140-0.171)
0.028
0.033
0.041
0.048
0.057
0.064
0.071
0.078
0.089
0.098
7-day
(0.026-0.030)
(0.031-0.036)
(0.038-0.045)
(0.044-0.052)
(0.052-0.061)
(0.058-0.069)
(0.064-0.077)
(0.071-0.085)
(0.080-0.097)
(0.087-0.106)
0.022
0.027
0.032
0.037
0.043
0.048
0.053
0.058
0.065
0.071
10-day
(0.021-0.024)
(0.025-0.029)
(0.030-0.035)
(0.034-0.040)
(0.040-0.046)
(0.044-0.052)
(0.049-0.057)
(0.053-0.063)
(0.059-0.070)
(0.064-0.076)
0.015
0.018
0.021
0.024
0.028
0.031
0.034
0.037
0.041
0.044
20-day
(0.014-0.016)
(0.017-0.019)
(0.020-0.023)
(0.022-0.026)
(0.026-0.030)
(0.028-0.033)
(0.031-0.036)
(0.034-0.040)
(0.037-0.044)
(0.040-0.048)
0.012
0.015
0.017
0.019
0.022
0.024
0.026
0.028
0.031
0.033
30-day
(0.012-0.013)
(0.014-0.016)
(0.016-0.019)
(0.018-0.021)
(0.020-0.024)
(0.022-0.026)
(0.024-0.028)
(0.026-0.030)
(0.028-0.033)
(0.030-0.036)
0.011
0.012
0.014
0.016
0.018
0.019
0.021
0.022
0.024
0.026
45-day
(0.010-0.011)
(0.012-0.013)
(0.013-0.015)
(0.015-0.017)
(0.017-0.019)
(0.018-0.021)
(0.019-0.022)
(0.021-0.024)
(0.022-0.026)
(0.024-0.028)
0.009
0.011
0.013
0.014
0.016
0.017
0.018
0.019
0.021
0.022
60-day
(0.009-0.010)
(0.010-0.012)
(0.012-0.014)
(0.013-0.015)
(0.015-0.017)
(0.016-0.018)
(0.017-0.019)
(0.018-0.021)
(0.019-0.022)
(0.020-0.024)
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

NOAA Atlas 14, Volume 2, Version 3 DUNN 4 NW
Station ID: 31-2500
' Location name: Erwin, North Carolina, USA*
Latitude: 35.3247°, Longitude:-78.6881°
Elevation:
Elevation (station metadata): 200 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 I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Average recurrence interval (years)
1
2
5
10
25
50
100
200
500
1000
0.437
0.513
0.594
0.659
0.734
0.791
0.844
0.894
0.954
1.00
5-min
(0.399-0.481)
(0.470-0.565)
(0.543-0.653)
(0.601-0.724)
(0.667-0.805)
(0.716-0.866)
(0.759-0.924)
(0.800-0.978)
(0.846-1.04)
(0.883-1.10)
0.697
0.821
0.951
1.06
1.17
1.26
1.34
1.42
1.51
1.58
10-min
(0.637-0.768)
(0.751-0.903)
(0.869-1.05)
(0.962-1.16)
1 (1.06-1.28)
1 (1.14-1.38)
1 (1.21-1.47)
1 (1.27-1.55)
(1.34-1.65)
(1.39-1.74)
0.872
1.03
1.20
1.33
1.48
1.59
1.70
1.79
1.90
1.99
15-min
(0.796-0.959)
(0.945-1.14)
1 (1.10-1.32)
1 (1.22-1.47)
1 (1.35-1.63)
1 (1.44-1.75)
1 (1.53-1.86)
1 (1.60-1.96)
(1.68-2.08)
(1.75-2.18)
1.20
1.43
1.71
1.93
2.20
2.40
2.60
2.78
3.02
3.22
30-min
(1.09-1.32)
1 (1.31-1.57)
1 (1.56-1.88)
(1.76-2.12)
1 (2.00-2.41)
1 (2.17-2.63)
1 (2.34-2.84)
1 (2.49-3.05)
(2.68-3.31)
(2.83-3.53)
1.49
1.79
2.19
2.52
2.93
3.25
3.58
3.90
4.34
4.69
60-min
(1.36-1.64)
(1.64-1.97)
(2.00-2.41)
(2.30-2.76)
(2.66-3.21)
(2.95-3.56)
(3.22-3.91)
(3.49-4.27)
(3.84-4.75)
(4.13-5.15)
1.75
2.12
2.63
3.06
3.63
4.09
4.56
5.06
5.72
6.29
2-hr
(1.58-1.96)
(1.91-2.36)
(2.38-2.93)
(2.76-3.41)
1 (3.24-4.04)
(3.65-4.55)
(4.04-5.07)
(4.45-5.61)
(4.98-6.35)
(5.43-6.99)
1.86
2.25
2.81
3.29
3.94
4.49
5.07
5.68
6.53
7.28
3-hr
(1.68-2.08)
(2.03-2.51)
(2.54-3.14)
(2.97-3.67)
(3.53-4.39)
(4.00-5.01)
(4.47-5.64)
(4.97-6.32)
(5.65-7.27)
(6.23-8.10)
2.22
2.68
3.35
3.94
4.73
5.41
6.13
6.89
7.97
8.91
6-hr
(2.02-2.47)
(2.44-2.98)
(3.04-3.72)
(3.56-4.37)
(4.25-5.24)
(4.83-5.98)
(5.41-6.76)
(6.03-7.59)
(6.88-8.79)
(7.60-9.84)
2.61
3.15
3.96
4.68
5.67
6.52
7.42
8.41
9.82
11.1
12-hr
(2.36-2.91)
(2.86-3.51)
(3.58-4.42)
(4.21-5.21)
(5.06-6.28)
(5.78-7.22)
(6.51-8.21)
(7.29-9.29)
(8.38-10.8)
(9.30-12.2)
3.05
3.70
4.74
5.58
6.75
7.72
8.73
9.80
11.3
12.5
24-hr
(2.78-3.35)
(3.38-4.07)
(4.31-5.22)
(5.06-6.13)
(6.10-7.42)
(6.95-8.48)
(7.83-9.59)
(8.75-10.8)
(10.0-12.5)
(11.1-13.8)
3.57
4.32
5.49
6.42
7.73
8.81
9.93
11.1
12.8
14.2
2-day
(3.26-3.90)
(3.95-4.71)
(5.01-5.99)
(5.85-7.01)
(7.01-8.44)
(7.94-9.62)
(8.92-10.9)
(9.93-12.2)
(11.4-14.1)
(12.5-15.6)
3.80
4.59
5.79
6.76
8.10
9.19
10.3
11.5
13.2
14.6
3-day
(3.49-4.13)
(4.22-4.99)
(5.31-6.29)
(6.18-7.33)
(7.37-8.79)
(8.33-9.98)
1 (9.32-11.2)
1 (10.4-12.6)
(11.8-14.5)
(13.0-16.0)
4.03
4.86
6.10
7.09
8.47
9.58
10.7
12.0
13.7
15.1
4-day
(3.73-4.36)
(4.49-5.26)
(5.62-6.60)
(6.51-7.65)
(7.73-9.14)
(8.72-10.3)
1 (9.73-11.6)
1 (10.8-13.0)
(12.3-14.9)
(13.4-16.4)
4.67
5.60
6.95
8.02
9.49
10.7
11.9
13.2
15.0
16.4
7-day
(4.30-5.07)
(5.16-6.09)
(6.39-7.56)
(7.34-8.70)
(8.66-10.3)
(9.72-11.6)
1 (10.8-12.9)
1 (11.9-14.3)
(13.4-16.3)
(14.6-17.9)
5.33
6.38
7.78
8.87
10.4
11.5
12.7
14.0
15.6
17.0
10-day
(4.97-5.72)
(5.94-6.85)
(7.23-8.36)
(8.22-9.52)
(9.56-11.1)
(10.6-12.4)
1 (11.7-13.7)
1 (12.8-15.0)
(14.2-16.9)
(15.4-18.3)
7.18
8.53
10.2
11.6
13.4
14.8
16.2
17.7
19.7
21.3
20-day
(6.68-7.72)
1 (7.94-9.17)
(9.51-11.0)
(10.7-12.4)
(12.4-14.4)
1 (13.7-15.9)
1 (14.9-17.5)
1 (16.2-19.1)
(18.0-21.2)
(19.3-23.0)
8.95
10.6
12.5
13.9
15.9
17.3
18.8
20.3
22.3
23.8
30-day
(8.34-9.63)
1 (9.86-11.4)
(11.6-13.4)
(12.9-15.0)
(14.7-17.1)
1 (16.0-18.7)
1 (17.4-20.2)
1 (18.7-21.8)
(20.4-24.0)
(21.7-25.7)
11.4
13.4
15.5
17.2
19.3
20.9
22.5
24.1
26.2
27.8
45-day
(10.7-12.1)
1 (12.6-14.3)
(14.6-16.6)
1 (18.0-20.6)
1 (19.5-22.4)
1 (21.0-24.1)
1 (22.4-25.8)
(24.2-28.1)
(25.6-29.9)
13.6
16.0
18.4
20.2
22.5
24.3
26.0
27.7
29.9
31.6
60-day
(12.8-14.5)
(15.0-17.0)
(17.3-19.6)
(18.9-21.5)
(21.1-24.0)
(22.7-25.9)
(24.3-27.8)
(25.8-29.6)
(27.8-32.0)
(29.2-33.9)
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

SUPPORT DOCUMENTS
Stream Classification
EST. 0 10

NC DENR - DIVISON OF WATER RESOURCES
.0311 CAPE FEAR RIVER BASIN
2B .0300
Name of Stream
Description
Class
Class Date
Index No.
Six Runs Creek
From Quewiffle Swamp to Black
C;Sw,ORW:+
06/01/94
18-68-2-(11.5)
River
Crane Creek
From source to Six Runs Creek
C;Sw
07/01/73
18-68-2-12
Jump -and -Run Branch
From source to Crane Creek
C;Sw
07/01/73
18-68-2-12-1
Buckhorn Creek (Boney Pond)
From source to Crane Creek
C;Sw
07/01/73
18-68-2-12-2
Wolf Pit Branch
From source to Buckhorn Creek
C;Sw
07/01/73
18-68-2-12-2-1
Bridge Branch
From source to Buckhorn Creek
C;Sw
07/01/73
18-68-2-12-2-2
Peters Branch
From source to Buckhorn Creek
C;Sw
07/01/73
18-68-2-12-2-3
Robinson Mill Branch
From source to Six Runs Creek
C;Sw
04/01/59
18-68-2-13
Mathis Mill Branch
From source to Six Runs Creek
C;Sw
04/01/59
18-68-2-14
Spearmans Mill Creek
From source to Six Runs Creek
C;Sw
04/01/59
18-68-2-15
Gaddy Branch
From source to Six Runs Creek
C;Sw
04/01/59
18-68-2-16
Tarkill Branch
From source to Six Runs Creek
C;Sw
04/01/59
18-68-2-17
Clear Run (Swamp)
From source to Black River
C;Sw
07/01/73
18-68-3
New Hope Creek
From source to Clear Run
C;Sw
07/01/73
18-68-3-1
Red Hill Branch
From source to New Hope Creek
C;Sw
07/01/73
18-68-3-1-1
Free Will Creek
From source to Clear Run
C;Sw
07/01/73
18-68-3-2
Beaverdam Creek
From source to Clear Run
C;Sw
07/01/73
18-68-3-3
Big Branch
From source to Black River
C;Sw
09/01/74
18-68-4
Juniper Branch
From source to Black River
C;Sw
04/01/59
18-68-5
Devane Branch
From source to Black River
C;Sw
04/01/59
18-68-6
Rocky Branch
From source to Devane Branch
C;Sw
04/01/59
18-68-6-1
Canty Mill Creek
From source to Black River
C;Sw
09/01/74
18-68-7
Cobb Branch
From source to Canty Mill Creek
C;Sw
09/01/74
18-68-7-1
Wild Cat Creek
From source to Black River
C;Sw
09/01/74
18-68-8
Keith Branch
From source to Black River
C;Sw
09/01/74
18-68-9
Kings Branch
From source to Black River
C;Sw
09/01/74
18-68-10
Cypress Lake
Entire lake and connecting stream to
C;Sw
04/01/59
18-68-11
Black River
South River
From source to Big Swamp
C;Sw
04/01/59
18-68-12-(0.5)
Black River (Little Black River) From source to South River C;Sw 09/01/74 18-68-12-1
(Popes Lake, Rhodes Pond)
Youngs Pond Entire pond and connectinq stream C;Sw 09/01/74 18-68-12-1-1
Big Branch
Juniper Creek
Mingo Swamp
East Mingo Creek
Stony Run (Hannas Pond)
Big Juniper Run (Jernigan Pond)
to Black River
From source to Black River
From source to Black River
From source to South River
From source to Mingo Swamp
From source to Mingo Swamp
From source to Mingo Swamp
C;Sw
09/01/74
18-68-12-1-2
C;Sw
09/01/74
18-68-12-1-3
C;Sw
09/01/74
18-68-12-2
C;Sw
09/01/74
18-68-12-2-1
C; Sw
09/01/74
18-68-12-2-2
C;Sw
09/01/74
18-68-12-2-3
37

SUPPORT DOCUMENTS
Hydrology Group - Soils
N
EST. 0 10

Appendices
Table 8.01d (continued)
Name
Depth
pH
K
Hydrology
Plasti-
_ Textural Classification -----------------------
Group
city
USDA
Unified
AASHTO
AYERSVTLLE
0-8
4.5-6.0
0.32
B
NP-I I
L, STL, STCL
ML, CL-ML, CL, SC
A-4, A-6
GR-L, GR-SIL,
SM, SM-SC, ML,
0-8
4.5-6.0
0.28
B
4-25
A-4, A-6
GR-SICL
SC
8-22
4.5-5.5
0.28
B
4-25
GR-SIL, GR-L, L
CL, CL-ML, ML
A-4, A-6, A-7
22-26
4.5-5.5
0.28
B
NP-10
GR-STL, GR-L
CL, CL-ML, ML
A-4
26-30
B
NP
30
B
NP
CN-SIL, CN-VFSL,
ML, CL, CL-ML,
BADIN
0-6
3.6-6.5
0.24
C
NP-10
A-4
CN-L
GM
6-25
3.6-5.5
0.24
C
15-35
STC, STCL, CN-STCL
CL, CH
A-6, A-7
25-40
C
NP
WB
40
C
NP
UWB
BALLAHACK
0-9
4.5-5.5
0.10
D
NP-10
FSL, SL, L
SM, SC. CL, ML
A-4
9-35
4.5-5.5
0.10
D
8-20
SCL, L
SC, CL
A-4, A-6
35-74
4.5-5.5
0.17
D
NP-10
SR-S-SC
SM, SC, ML, CL
A-2, A-4
BARCLAY
0-57
4.5-6.0
0.43
C
NP-7
L, STL, VFSL
CL-ML, ML
A-4
57-72
4.5-6.0
0.43
C
NP
FS, LS, FSL
SM, SP-SM
A-2
SM-SC, SM, CL,
BAYBORO
0-14
4.5-5.5
0.15
D
NP-7
FSL
A-4
ML, ML
0-14
4.5-5.5
0.17
D
4-20
L, CL
CL, ML, CL-ML
A-6, A-7
14-64
4.5-5.5
0.32
D
20-40
CL, SC, C
CL, CH
A-7
BAYMEADE
0-36
4.5-6.5
0.10
A
NP
FS, S
SM, SP-SM
A-2, A-3
0-36
45-6.5
0.10
A
NP
LS, LFS
SM
A-2-4
36-49
4.5-6.5
0.10
A
2-9
FSL, SCL, SL
SC, SM, SM-SC
A-2, A-4
49-78
4.5-6.5
0.10
A
NP
LFS, S, LS
SM, SP-SM
A-2, A-3
BELHAVEN
0-26
4.5 &._
D
NP
MUCK
PT
26-32
3.6-5.5
0.24
D
NP-10
SL, FSL
SM, SC, SM-SC
A-2, A-4
CL, CLrML, SC,
32-65
3.6-6.5
0.24
D
4-15
L, CL, SCL
A-4, A-6
SM-SC
65-72
3.6-6.5
0.15
D
NP
SR-S, FS
SM, SP-SM
A-2, A-3
BERTTE
0-17
4.5-6.5
0.17
B
NP-4
LS, LFS
SM
A-2
0-17
4.5-6.5
0.20
B
NP-7
SL, FSL
SM, SM-SC
A-2, A-4
SC, CL, SM-SC,
17-42
4.5-6.5
0.24
B
4-16
SCL, CL, SL
A-2, A-4,A-6
CL-ML
42-57
4.5-6.0
0.24
B
NP-8
FSL, SL, SCL
SM, SM-SC
A-2, A-4
57-85
4.5-6.0
0.17
B
NP-6
SL, LFS, FS
SM, SM-SC, SP-SM
A-2, A-4
BTBB 0-12
4.5-5.5
0.20
C
NP-7
SL, FSL
[,
A-2, A-4
CI
0-12
4.5-5.5
0.28
C
NP-7
L, SIL
ML, CL-ML
A-4
0-12
4.5-5.5
0.15
C
NP
S, LS
SM, SP-SM
A-2, A-3
SM, SM-SC, ML,
12-60
4.5-5.5
0.37
C
NP-7
SL, L, STL
A-2, A-4
CL-ML
BTLTMORE 0-10
5.1-7.8
0.15
A
NP-4
FSL, SL, LFS
SM
A-2, A-4
10-60
5.1-7.8
0.10
A
NP
LS, LFS, S
SM, SP-SM
A-2
BLADEN 0-14
3.6-5.5
0.24
D
NP
FSL, SL
SM
A-2, A-4
0-14
3.6-5.5
037
D
NP-10
L, STL
CL, ML, CL-ML
A-4
14-41
3.6-5.5
D
23-45
C, SC
CL, CH
A-7
41-62
3.6-5.5
D
8-35
C, SC, CL
CL, CH, SC
A-4, A-6, A-7
62-80
D
NP
Var
BL ANEY 0-25
4.5-6.0
0.15
B
NP
S, LS
SM, SP-SM
A,2, A-3
0-25
4.5-6.0
0.10
B
NP
COS, LCOS
SM, SP-SM
A-2, A-3,
A-1-B
25-50
4.5-5.5
0.28
B
NP-20
SCL, SL
SM, SC, SM-SC
A-2, A-4, A-
6, A-1-B
50-65
4.5-5.5
0.28
B
NP-14
SL, SCL, LS
SM, SC, SM-SC
A-2, A-4, A-
6, A-1-B
See Tables 8.01b, 8.01c and Figure
8.01d for definition of symbols.
8.01.15

Appendices
Table 8.01d (continued)
Name
Depth
pH
K
Hydrology
Plasti-
- ---------------------
Textural Classification' -----------------------
Group
city
USDA
Unified
AASHTO
CROATAN
0-28
4.5
D
NP
MUCK
PT
28-38
3.6-6.5
0.17
D
NP-10
SL, FSL, MK-SL
SM, Sc, SM-SC
A-2, A-4
CL, CL-ML, SC,
38-60
3.6-6.5
0.24
D
4-15
L, CL, SCL
A-4, A-6
SM-SC
60-80
D
NP
Var
CURRTTUCK
0-14
4.5-5.5
D
NP
MUCK, MPT
PT
A-8
14-28
3.6-5.5
D
NP
MUCK
PT
A-8
28-60
3.6-5.5
D
NP
LS, S
SM, SP-SM
A-2, A-3
DARE
0-70
3.6-4.4
D
NP
MUCK
PT
70-80
3.6-6.0
0.15
D
NP
SR-FS, LS
SM, SP-SM
A-2, A-3
DAVIDSON
0-7
4.5-6.5
0.28
B
3-15
L
CL, CL-ML, ML
A-4, A-6
CL, SC, CL-ML,
0-7
4.5-6.5
0.28
B
5-18
CL, SCL
A-6, A-4
SM-SC
7-12
4.5-6.0
0.32
B
11-25
CL
CL
A-6
12-53
4.5-6.0
0.24
B
12-33
C
CL, CH, ML, MH
A-7, A-6
53-72
4.5-6.0
0.28
B
7-30
C, CL, SCL
CL, ML, MH
A-4, A-6, A-7
DELANCO
0-11
3.6-5.5
0.37
C
NP-15
SIL, FSL
ML, CL, SM ,SC
A-4, A-6
11-36
3.6-5.5
0.32
C
10-25
STCL, CL, L
CL, ML
A-6, A-7
36-50
3.6-5.5
0.28
C
NP-15
SR-GR-SL-STCL
ML, CL, SM, SC
A-2, A-4, A-6
DELOSS
048
4.5-6.5
0.15
B/D
NP-4
LFS
SM
A-2
0-18
4.5-6.5
0.24
B/D
NP-7
SL, FSL, L
SM, SM-SC, ML,
A-2, A-4
CL-ML
SM-SC, SC, CL,
18-56
4.5-5.5
0.24
B/D
4-22
SCL, CL, FSL
A-4, A-6, A-7
ML, CL
56-80
B/D
NP
Var
DOROVAN
0-3
3.6-4.4
D
NP
MPT, MUCK
PT
3-74
3.6-4.4
D
NP
MUCK
PT
SP-SM, SM-SC,
A-1, A-3, A-4,
74-99
4 i-i i
n
NP-7
S LC L
-- ---
-
-
- -- -
cnn
e_ _I
)OTHAN 0-13
4.5-5.5
0.15
B
NP
LFS, LS
SM
A-2
0-13
4.5-5.5
0.24
B
NP-5
FSL, SL
SM, SM-SC
A-2, A-4
13-33
4.5-5.5
0.28
B
NP-16
SCL, SL, FSL
SM-SC, Sc, SM
A-2, A-4, A-6
33-60
4.5-5.5
0.28
B
4-23
SCL, SC
SM-SC, CL-ML,
A-2, A-4, A-6,
CL
A-7
SM, SC, SM-SC,
CL-ML
0-9
4.5-5.5
0.17
C
NP-7
LFS, LS
SM, SM-SC
A-2
SM, Sc, SM-SC,
9-37
4.5-5.5
0.17
C
NP-10
FSL, SL, L
A-2, A-4
CL-ML
SM, SP-SM,
37-66
4.5-6.5
0.17
C
NP-7
S, LS, FSL
A-1, A-2, A-3
SM-SC
DUCKSTON
0-72
3.6-8.4
0.10
A/D
NP
S, FS
SP-SM, SP
A-3
DUNBAR
0-8
4.5-5.5
0.32
D
NP-7
SL, FSL, L
SM, SM-SC
A-2, A-4
8-80
3.6-5.5
0.32
D
18-35
SC, CL, C
CL, CH
A-6, A-7
DUPLIN
0-8
5.1-7.3
0.24
C
NP-7
SL, FSL, LS
SM, SM-SC
A-2, A-4
8-80
4.5-5.5
0.28
C
13-35
SC, CL, C
CL, CH, SC
A-6, A-7
DURHAM
0-16
4.5-6.0
0.17
B
NP-3
LCOS, LS
SM
A-2
0-16
4.5-6.0
0.24
B
NP-7
SL, FSL
SM, SM-SC
A-2, A-4
16-36
4.5-5.5
0.20
B
10-25
SCL, CL
SC, CL
A-2, A-6, A-7
36-42
4.5-5.5
0.20
B
13-28
CL, SC, SCL
SC, CL
A-6, A-7
42-48
4.5-5.5
0.20
B
NP-10
SCL, SL
SM, SC, SM-SC
A-2, A-4
48-60
4.5-5.5
0.17
B
NP-7
LS, SL, SCL
SM, SM-SC
A-2, A-4
EDNEYVILLE
0-10
4.5-6.0
0.24
B
NP-7
FSL, SL
SM, SM-SC
A-2, A-4
0-10
4.5-6.0
0.28
B
NP-10
L, STL
ML, CL-ML, CL
A-4
10-60
4.5-6.0
0.20
B
6-15
FSL, SL, L
SM, SM-SC
A-2, A-4, A-6
'See Tables 8.01b,
8.01c and Figure
8.01d for
definition of symbols.
8.01.19

Table 8.01d (continued)
Name Depth pH
K
Hydrology
Plasti-
_
Textural Classification -----------------------
Group
city
USDA
Unified
AASHTO
LUCY 0-24 5.1-6.0
0.15
A
NP
LS, S, LFS
SM, SP-SM
A-2
24-35 4.5-5.5
0.24
A
NP-15
SL, FSL, SCL
SM, SC, SM-SC
A-2, A-4, A-6
35-70 4.5-5.5
0.28
A
3-20
SL, SCL, CL
Sc, SM-SC, SM
A-2, A-6, A-4
LUMBEE 0-14 4.5-5.5
0.24
B/D
NP-7
LS, SL, FSL
SM, SM-SC
A-2, A-4
14-36 4.5-5.5
0.32
B/D
7-25
SCL, SL, CL
SC, CL
A-4, A-6, A-7
16-60 -5 5
-?
LYNCHBURG 0-10 3.6-5.5 0.15
C NP-4 LS, LFS
SM, SP-SM
A-2
SM, ML, SM-SC,
0-10 3.6-5.5 0.20
C NP-7 SL, FSL, L
A-2, A-4
CL,ML
SM-SC, SC, CL,
10-62 3.6-5.5 0.20
C 4-18 SCL, SL, CL
A-2, A-4, A-6
CL,ML
LYNN HAVEN
0-16
3.6-5.5
0.10
B/D
NP
S, FS
SP, SP-SM, SM
A-3, A-2-4
16-30
3.6-5.5
0.15
B/D
NP
S, FS, LS
SM, SP-SM
A-3, A-2-4
30-75
3.6-5.5
0.10
B/D
NP
S, FS
SP, SP-SM
A-3, A-2-4
MADISON
0-6
4.5-6.0
0.24
B
NP-8
FSL, SL
SM, SM-SC
A-2, A-4
0-6
4.5-6.0
0.15
B
NP-7
GR-FSL, GF-SL
SM, SM-SC
A-2, A-4
0-6
4.5-6.0
0.28
B
7-20
CL, SCL
CL
A-4, A-6
6-30
4.5-5.5
0.32
B
12-43
C, CL, SC
MH, ML
A-7
30-35
4.5-6.0
0.28
B
7-20
L, SCL, CL
CL
A-4, A-6
35-66
B
WB
MANTACHIE
0-11
4.5-5.5
0.37
C
NP-10
SIL
ML, CL-ML, CL
A-4
0-11
4.5-5.5
0.28
C
5-15
CL
CL-ML, CL
A-4, A-6
CL-ML, SM-SC,
0-11
4.5-5.5
0.28
C
NP-5
FSL, SL, L
A-4
SM, ML
CL, SC, SM-SC,
11-61
4.5-5.5
0.28
C
5-15
L, CL, SCL
A-4, A-6
CL-ML
MANTEO
0-6
3.6-5.5
0.28
C/D
2-15
CN-SIL, CN-L
GM, ML, CL, GC
A-4
0-6
3.6-5.5
0.28
C/D
2-15
CN-VSIL, CN-VL
GM, ML, CL, GC
A-1, A-2, A-4,
A-6
6-15
3.6-5.5
0.28
C/D
2-20
CN-VSIL, CN-SIL,
GM GC, ML, CL
A-1, A-2, A-4,
CN-CL
A-6
15
C/D
UWB
MARLBORO
0-9
5.1-6.5
0.15
B
NP-4
LS, LFS
SM
A-2
SM, SM-SC, ML,
0-9
5.1-6.5
0.20
B
NP-7
SL, FSL, VFSL
A-2, A-4
CL-ML
9-60
4.5-6.0
0.20
B
6-20
SC, CL,C
CL, ML, CL-ML
A-4, A-6, A-7
60-72
4.5-6.0
0.20
B
6-20
SCL, SC, C
CL, ML, SM-SC
A-4, A-6, A-7
MASADA
0-10
4.5-5.5
0.32
C
NP-8
FSL, L
ML, SM, SC, CL
A-4, A-6
10-55
4.5-5.5
0.24
C
20-35
CL, C, GR-C
CH, CL
A-7, A-6
55-72
4.5-5.5
0.24
C
15-25
L, CL, GR-SCL
CL, ML
A-6, A-7, A-4
MATTAMUSKEET
0-22
4.5
D
NP
MUCK
PT
22-72
3.6-5.5
D
NP
LS, S, FS
SM, SP-SM
A-2, A-3
MAXTON
0-12
45-6.0
0.20
B
NP-7
SL, FSL
SM, SM-SC
A-2
0-12
4.5-6.0
0.15
B
NP
LS, LFS
SM, SP-SM
A-2
12-33
4.5-5.5
0.24
B
4-15
SCL, SL
Sc, SM-SC
A-4, A-6, A-2
33-60
4.5-5.5
0.10
B
NP
SR-LS-S
SM, SP-SM, SP
A-2, A-3
MAYODAN
0-12
4.5-6.0
0.24
B
NP-5
SL, FSL, SIL
SM, ML, SM-SC
A-2, A-4
GP -GM, GM ,SM,
0-12
4.5-6.0
0.15
B
NP-4
GR-SL, GR-FSL
A-1
SP-SM
A-4, A-6,
0-12
4.5-6.0
0.32
B
7-26
CL, SCL
CL, SC
A-7-6
A-4, A-6,
12-18
4.5-6.0
0.32
B
7-26
STCL, CL, SCL
CL, ML, SC
A-7-6
18-47
4.5-5.5
0.28
B
15-45
C, SC, STC
MH, CH, CL, ML
A-7
47-60
4.5-5.5
B
Var
'See Tables 8.01 b,
8.01 c and Figure 8.01 d for definition
of symbols.
8.01.24

0
Table 8.01d (continued)
Name Depth pH K Hydrology Plasti- - Textural Classification'
--------------------- -----------------------
Group city
USDA Unified AASHTO
NORFOLK 0-17
4.5-6.0
0.17
B
NP-14
SL, FSL
SM, SM-SC, SC
A-2
0-17
4.5-6.0
0.20
B
NP
LS, LFS
SM
A-2
5C, SM-SC, CL,
17-38
4.5-5.5
0.24
B
4-15
SL, SCL, CL
-L-ML
A-2, A-4, A-6
�C,
SM-SC, CL,
A-4, A-6,
38-70
4.5-5.5
0.24
B
4-23
SCL, SC, CL
CL-ML
A-7-6
70-99
B
Var
OAKBORO 0-10
4.5-6.5
0.28
C
NP-10
SIL, L
ML, CL-ML, CL
A-4, A-6
10-46
4.5-6.5
0.28
C
NP-15
L, SIL, SICL
ML, CL-ML, CL
A-4, A-6
46
C
UWB
SM, ML, SM-SC,
OCHLOCKONEE
0-6
4.5-5.5
0.20
B
NP-5
FSL, SL
A-4, A-2
CL-ML
0-6
4.5-5.5
0.24
B
NP-7
SIL, L
ML, CL-ML
A-4
0-6
4.5-5.5
0.17
B
NP
LS, LFS
SM
A-2, A-4
6-44
4.5-5.5
0.20
B
NP-9
FSL, SL, STL
SM, SL, SC, CL
A-4
44-72
4.5-5.5
0.17
B
NP-9
LS, SL, SIL
SM, ML, CL, SC
A-4, A-2
OCILLA
0-28
4.5-5.5
0.10
C
NP
LS, LFS, S
SM, SP-SM
A-2, A-3
28-67
4.5-5.5
0.24
C
NP-18
SL, SCL
SM, CL, SC
A-2, A-4, A-6
OLUSTEE
0-8
3.6-5.5
0.10
B/D
NP
S, FS
SP-SM, SM
A-3, A-2-4
8-21
3.6-5.5
0.15
B/D
NP
S, FS
SP-SM, SM
A-3, A-2-4
21-35
4.5-5.5
0.10
B/D
NP
S, FS
SP-SM, SM
A-3, A-2-4
35-62
4.5-5.5
0.24
B/D
8-15
SCL, SL
SC
A-2, A-4, A-6
62-74
4.5-5.5
0.28
B/D
15-25
Sc
SC, CL
A-6, A-7
ONSLOW
0-17
3.6-5.5
0.17
B
NP
LFS, LS
SM-SP-SM
A-2, A-3, A-4
0-17
3.6-5.5
0.20
B
NP-10
FSL, SL
SM, ML, SC, CL
A-2, A-4
CL, SM-SC,
17-53
3.6-5.5
0.24
B
NP-14
SCL, SL, CL
5M ,
A-2, A-4, A-6
53-80
B
Var
SM, ML, CL-ML,
ORANGE
0-10
5.1-6.5
0.49
D
NP-10
STL, L
A-4
SM, ML, CL-ML,
0-10
5.1-6.5
0.32
D
NP-7
FSL, SL
A-4
SM-SC
10-38
5.1-6.5
0.28
D
45-70
C, SLC, SICL
CH
A-7
38-58
5.6-7.8
0.28
D
10-25
SIL, CNV-SIL, SCL
SC, CL, GC
A-6, A-7
58
D
UWB
ORANGEBURG
0-7
4.5-6.0
0.10
B
NP
LS, LFS, S
SM
A-2
0-7
4.5-6.0
0.20
B
NP
SL, FSL
SM
A-2
0-7
4.5-6.0
0.24
B
3-16
SCL
SM, SM-SC, SC
A-4, A-6
7-12
4.5-6.0
0.20
B
NP-4
SL
SM
A-2
SC, CL, SM,
12-54
4.5-5.5
0.24
B
3-19
SCL, SL
A-6, A-4
SM-SC
54-64
4.5-5.5
0.24
B
8-21
SCL, SC, SL
SC, CL
A-6, A-4, A-7
OSIER
0-8
3.6-6.0
0.10
A/D
NP
S, LS, FS
SP-SM
A-2, A-3
0-8
3.6-6.0
0.15
A/D
NP
FSL, LFS
SM
A-2
8-48
3.6-6.0
0.10
A/D
NP
S, LS, LFS
SP-SM, SM
A-2, A-3
A-1, A-3,
48-75
3.6-6.0
0.05
A/D
NP
COS, S, FS
SP, SP-SM
ML, CL-ML, SM-
A-2-4
OTEEN
0-6
5.1-7.3
0.24
C
NP-7
FSL, SL, L
A-2, A-4
SC, SM
0-6
5.1-7.3
0.17
C
NP-7
GR-FSL, GR-L, GR-SL
SM, SM-SC
A-2, A-4, A-1
6-17
5.1-7.3
0.32
C
11-30
L, CL, C
CL
A-6, A-7
17-60
C
WB
PACOLET
0-3
4.5-6.5
0.20
B
NP-7
SL, FSL, L
SM, SM-SC
A-2, A-1-13
0-3
4.5-6.5
0.24
B
4-17
CL, SCL
SM-SC, SC
A-4, A-6
0-3
4.5-6.5
0.15
B
NP-3
LS
SM
A-2
3-29
4.5-6.0
0.28
B
11-30
SC, CL, C
ML, MH
A-6, A-7
CL, CL-ML, SM-
29-52
4.5-6.0
0.28
B
5-15
CL, SCL, SL
A-2, A-4, A-6
SC, Sc
52-70
4.5-6.0
0.28
B
NP-6
SL, FSL, L
SM, SM-SC
A-4, A-2-4
See Tables 8.01 b,
8.01 c and
Figure 8.01 d for definition of symbols.
8.01.26

Table 8.01d (continued)
Name
Depth
pH
K
Hydrology
Plasti-
_
Textural Classification -----------------------
Group
city
USDA
Unified
AASHTO
PORTERS
0-7
4.5
0.24
B
NP-10
FSL, SL
SM, SM-SC
A-2, A-4
0-7
4.5-6.0
0.28
B
NP-10
L, STL
ME, CL, CL-ML
A-4
7-42
45-6.0
0.24
B
NP-7
L, SL, FSL
SM, SM-SC
A-2, A-4
42-60
B
UWB
PORTSMOUTH
0-19
3.6-5.5
0.24
B/D
NP-7
SL, FSL, L
SM, SM-SC, ME
A-2, A-4
19-35
3.6-5.5
0.28
B/D
7-18
L, SCL, CL
SC, CL-ML, CL
A-4, A-6
35-38
3.6-5.5
0.17
B/D
NP-4
LS, SL
SM
A-2
38-72
3.6-6.0
0.17
B/D
NP
SR-COS-LS
SP-SM, SP, SM
A-1, A-2, A-3
PUNGO
0-72
4.5
D
NP
MUCK
PT
72-84
3.6-7.3
0.24
D
15-35
C, SIC, SC
CH, CL,SC
A-7, A-6
RABUN
0-9
5.1-6.5
0.32
B
3-20
L, CL, SIL
ME, CL, SM, SC
A-6, A-7, A-4
0-9
5.1-6.5
0.20
B
3-12
GR-L, GR-CL
SM, Sc, SM-SC
A-6, A-4
9-37
5.1-6.5
0.28
B
12-30
CL, C, SIC
ME, CL, MH, CH
A-7
37-48
5.1-6.5
0.28
B
11-23
C, CL, SICL
ME, CL
A-7, A-6
48-62
B
W B
RAINS 0-12 4.5-6.5 0.10
B/D
NP S, FS
SP-SM A-3, A-2-4
12-62 4.5-5.5 0.24
B/D
8-18 SCL
SC A-2-6, A-2-4
62-85 4.5.5 0.20
B/D
NP-7 LS, LFS, SL
SM, SM-SC A-2-4
SM, CL-ML, ME,
�ruvuc
v-
..
v.��
v
ivr-i
�,, u,
SM-SC
'
SM, CL-ML, ME,
5-18
4.5-5.5
0.17
D
NP-7
L, SL, FSL
A-4, A-2
SM-SC
18
D
UWB
RANGER
0-6
4.5-5.5
0.24
C
2-8
CN-SIL
ME, CL-ML, CL
A-4
CN-SICL, CNV-
6-26
4.5-5.5
0.24
C
2-10
S N-SIL,
GM,CG, GM -GC
A-4, A-2
RIDGELAND
0-8
3.6-6.5
0.10
B/D
NP
S, FS, LFS
SP-SM, SM
A-2, A-3
8-15
3.6-6.5
0.15
B/D
NP
S, FS, LFS
SP-SM, SP, SM
A-2, A-3
15-35
3.6-6.5
0.15
B/D
NP
S, FS, LFS
SP SM, SP SM
A-2, A-3
35-80
3.6-6.5
0.15
B/D
NP
S, FS, LFS
SP-SM, SP, SM
A-2, A-3
RIMINI
0-58
3.6-6.0
0.10
A
NP
S, FS
SP, SP-SM
A-3
58-70
3.6-6.0
0.10
A
NP
S, FS
SP, SP-SM
A-3
70-80
36.-6.0
0.10
A
NP
S, FS
SP SP-SM
A-3
SM, ME, CL-ML,
ROANOKE
0-7
3.6-5.5
0.28
D
NP-7
FSL
A-2, A-4
SM-SC
SM-SC, CL-ML,
0-7
3.6-5.5
0.37
D
5-16
SIL, L
A-4, A-6
CL, SC
0-7
3.6-5.5
0.37
D
14-20
STCL, CL
CL
A-6, A-7
7-12
3.6-5.5
0.24
D
14-20
CL, SICL
CL
A-6, A-7
12-50
3.6-5.5
0.24
D
22-40
C, SIC, CL
CH, CL
A-7
CL-ML, GM -GC,
A-2, A-4, A-6,
50-72
3.6-6.5
0.24
D
NP-40
SR, SC-C
CL, ME
A-7
ROPER
0-15
3.6-5.5
B/D
NP
MUCK
PT
15-42
3.6-5.5
0.43
B/D
8-25
SIL, SICL, L
CL
A-4, A-6
42-55
5.6-7.8
0.43
B/D
8-25
SIL, SICL, L
CL
A-4, A-6
55-72
5.6-7.8
B/D
Var
ROSMAN
0-50
5.1-6.5
0.24
B
4-15
L, FSL, STL
ME, CL-ML
A-4
SM, ME, CL-ML,
50-60
5.1-6.5
0.10
B
NP-7
SR-GR-S-GR-C
A-4
SM-SC
RUMFORD
0-17
3.6-5.5
0.17
B
NP
LFS, LS
SM
A-2, A-1
0-17
3.6-5.5
0.24
B
NP-6
FSL, SL
SM, SM-SC
A-2, A-4
17-37
3.6-6.0
0.17
B
NP-12
FSL, SL, SCL
SM, Sc, SM-SC
A-2, A-4, A-6
A-1, A-2, A-3,
37-60
3.6-6.5
0.17
B
NP-6
SR-SL-GR-S
SM, SP, GP, GM
A-4
'See Tables 8.01 b, 8.01 c and Figure
8.01 d for
definition of symbols.
8.01.28

CALCULATIONS & ANALYSIS
Weighted Curve Number
N
EST. 0 10

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryns Retreat
Date
4/7/2021
Pre -Developed - Drainage Area No. 1
Curve Numbers for Hydrologic Soil Group
A
B
C D
Open Space (Lawns, Parks)
Poor Condition
68
79
86 89
Fair Condition
49
69
79 84
Good Condition
39
61
74 80
Impervious Areas
Parking Lots, Roofs
Paved; Curbs
98
98
98 98
Paved; Open Ditches
83
89
98 98
Gravel
76
85
89 91
Dirt
72
82
85 88
Woods
Poor Condition
45
66
77 83
Fair Condition
36
60
73 79
Good Condition
30
55
70 77
Residential
1/8 acre or less
65
77
85 92
1/4 acre
38
61
75 87
1/3 acre
30
57
72 86
1/2 acre
25
54
70 85
1 acre
20
51
68 84
2 acre
12
46
65 82
Types of Soils with in Drainage Area
Soil Area in Drainage Area
Soil Name Hydrologic Group
Drainage Area = 45.60 ac
Bibb C
Total Area in "A" Soils = 0.00 ac
Dothan B
Total Area in "B" Soils 34.66 ac
Lynchburg C
Total Area in "C" Soils 10.94 ac
Norfolk B
Total Area in "D" Soils = 0.00 ac
Rains B
Poor Fair Good
Weighted CN Value 76 68 62
Use the following CN Values for each Land Use
Use the following CN Values for each Land Use
Poor
Fair
Good
Open Space =
81
71
64
Impervious Surface =
98
98
98
Wooded Area =
69
63
59
Gravel Area =
86
86
86
Land Uses in Sub -Basin
Open Space
26.36
ac
Impervious
0.00
ac
Wooded
19.24
ac
Gravel
ac

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryn's Retreat
Date
4/7/2021
Post -Developed - Drainage Area By -Pass
Curve Numbers for Hydrologic Soil Group
A
B
C D
Open Space (Lawns, Parks)
Poor Condition
68
79
86 89
Fair Condition
49
69
79 84
Good Condition
39
61
74 80
Impervious Areas
Parking Lots, Roofs
Paved; Curbs
98
98
98 98
Paved; Open Ditches
83
89
98 98
Gravel
76
85
89 91
Dirt
72
82
85 88
Woods
Poor Condition
45
66
77 83
Fair Condition
36
60
73 79
Good Condition
30
55
70 77
Residential
1/8 acre or less
65
77
85 92
1/4 acre
38
61
75 87
1/3 acre
30
57
72 86
1/2 acre
25
54
70 85
1 acre
20
51
68 84
2 acre
12
46
65 82
Types of Soils with in Drainage Area
Soil Area in Drainage Area
Soil Name Hydrologic Group
Drainage Area = 19.00 ac
Bibb C
Total Area in "A" Soils = 0.00 ac
Dothan B
Total Area in "B" Soils 14.44 ac
Lynchburg C
Total Area in "C" Soils 4.56 ac
Norfolk B
Total Area in "D" Soils = 0.00 ac
Rains B
Poor Fair Good
Weighted CN Value 72 65 6®
Use the following CN Values for each Land Use
Use the following CN Values for each Land Use
Poor
Fair
Good
Open Space =
81
71
64
Impervious Surface =
98
98
98
Wooded Area =
69
63
59
Gravel Area =
86
86
86
Land Uses in Sub -Basin
Open Space
4.60
ac
Impervious
0.00
ac
Wooded
14.40
ac
Gravel
ac

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryn's Retreat
Date
4/7/2021
Post -Developed - Drainage Area to SCM#1
Curve Numbers for Hydrologic Soil Group
A
B
C D
Open Space (Lawns, Parks)
Poor Condition
68
79
86 89
Fair Condition
49
69
79 84
Good Condition
39
61
74 80
Impervious Areas
Parking Lots, Roofs
Paved; Curbs
98
98
98 98
Paved; Open Ditches
83
89
98 98
Gravel
76
85
89 91
Dirt
72
82
85 88
Woods
Poor Condition
45
66
77 83
Fair Condition
36
60
73 79
Good Condition
30
55
70 77
Residential
1/8 acre or less
65
77
85 92
1/4 acre
38
61
75 87
1/3 acre
30
57
72 86
112 acre
25
54
70 85
1 acre
20
51
68 84
2 acre
12
46
65 82
Types of Soils with in Drainage Area
Soil Area in Drainage Area
Soil Name Hydrologic Group
Drainage Area = 4.20 ac
Bibb C
Total Area in "A" Soils = 0.00 ac
Dothan B
Total Area in "B" Soils 3.19 ac
Lynchburg C
Total Area in "C" Soils 1.01 ac
Norfolk B
Total Area in "D" Soils = 0.00 ac
Rains B
Poor Fair Good
Weighted CN Value 91 87 83
Use the following CN Values for each Land Use
Use the following CN Values for each Land Use
Poor
Fair
Good
Open Space =
81
71
64
Impervious Surface =
98
98
98
Wooded Area =
69
63
59
Gravel Area =
86
86
86
Land Uses in Sub -Basin
Open Space
1.80
ac
Impervious
2.40
ac
Wooded
0.00
ac
Gravel
ac

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryn's Retreat
Date
4/7/2021
Post -Developed - Drainage Area to SCM#2
Curve Numbers for Hydrologic Soil Group
A
B
C D
Open Space (Lawns, Parks)
Poor Condition
68
79
86 89
Fair Condition
49
69
79 84
Good Condition
39
61
74 80
Impervious Areas
Parking Lots, Roofs
Paved; Curbs
98
98
98 98
Paved; Open Ditches
83
89
98 98
Gravel
76
85
89 91
Dirt
72
82
85 88
Woods
Poor Condition
45
66
77 83
Fair Condition
36
60
73 79
Good Condition
30
55
70 77
Residential
1/8 acre or less
65
77
85 92
1/4 acre
38
61
75 87
1/3 acre
30
57
72 86
1/2 acre
25
54
70 85
1 acre
20
51
68 84
2 acre
12
46
65 82
Types of Soils with in Drainage Area
Soil Area in Drainage Area
Soil Name Hydrologic Group
Drainage Area = 16.10 ac
Bibb C
Total Area in "A" Soils = 0.00 ac
Dothan B
Total Area in "B" Soils 12.24 ac
Lynchburg C
Total Area in "C" Soils 3.86 ac
Norfolk B
Total Area in "D" Soils = 0.00 ac
Rains B
Poor Fair Good
Weighted CN Value 91 87 83
Use the following CN Values for each Land Use
Use the following CN Values for each Land Use
Poor
Fair
Good
Open Space =
81
71
64
Impervious Surface =
98
98
98
Wooded Area =
69
63
59
Gravel Area =
86
86
86
Land Uses in Sub -Basin
Open Space
6.90
ac
Impervious
9.20
ac
Wooded
0.00
ac
Gravel
ac

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryn's Retreat
Date
4/7/2021
Post -Developed - Drainage Area to SCM#3
Curve Numbers for Hydrologic Soil Group
A
B
C D
Open Space (Lawns, Parks)
Poor Condition
68
79
86 89
Fair Condition
49
69
79 84
Good Condition
39
61
74 80
Impervious Areas
Parking Lots, Roofs
Paved; Curbs
98
98
98 98
Paved; Open Ditches
83
89
98 98
Gravel
76
85
89 91
Dirt
72
82
85 88
Woods
Poor Condition
45
66
77 83
Fair Condition
36
60
73 79
Good Condition
30
55
70 77
Residential
1/8 acre or less
65
77
85 92
1/4 acre
38
61
75 87
1/3 acre
30
57
72 86
1/2 acre
25
54
70 85
1 acre
20
51
68 84
2 acre
12
46
65 82
Types of Soils with in Drainage Area
Soil Area in Drainage Area
Soil Name Hydrologic Group
Drainage Area = 6.61 ac
Bibb C
Total Area in "A" Soils = 0.00 ac
Dothan B
Total Area in "B" Soils 6.61 ac
Lynchburg C
Total Area in "C" Soils 0.00 ac
Norfolk B
Total Area in "D" Soils = 0.00 ac
Rains B
Poor Fair Good
Weighted CN Value 88 82 78
Use the following CN Values for each Land Use
Use the following CN Values for each Land Use
Poor
Fair
Good
Open Space =
79
69
61
Impervious Surface =
98
98
98
Wooded Area =
66
60
55
Gravel Area =
85
85
85
Land Uses in Sub -Basin
Open Space
3.55
ac
Impervious
3.06
ac
Wooded
0.00
ac
Gravel
ac

CALCULATIONS & ANALYSIS
SCM Design Worksheets
N
EST. 0 10

Per ject Data
Revisions
Project #
2018-002
No
Date
Description
Project Name
Kathryn's Retreat
1
8/30/2021
NCDENR Revisions
Date
10/6/2021
Wet Detention Pond #3
1) Calculate percent impervious draining to pond.
Impervious
Drainage Area = 6.61 acres
Road/Parking
0.42 ac / sf
1&
Impervious Area = 3.21 acres
Sidewalk
0.13 ac / sf
5E
Lots
2.17 ac / sf
94:
% Imperv. = 48.62 %
Driveways
0.19 ac / sf
8C
Ex. Street
0.31 ac / sf
13
2) Find the volume of the 1.0" storm using the "Simple Method"
(Schueler 1987):
1
The volume of the 1" storm must be detained in the pond above the permanent pool and must be drawn down over a
period of two to five days.
Rv = 0.05 + 0.009 (1)
Rv = runoff coefficient (ratio of runoff to rainfall in inches)
I = percent impervious
Rv = 0.488 in/in
Volume of 1.0" storm (must exceed 3630 cf):
JCf'IL
WQv = 3630 x RD x Rv X A
36823_$
WQv =volume of runoof gnerated from design storm
Ro = Design storm = 1 inch
. �j'F� 17�
Rv= Runoff Coef= 0.488 inch/inch
2021+.1 �1 -
A= Drainage Area = 6.61 acre
0 ^ 1001
`F
Vr ft
WO11,699
3) Determine Surface Area to Drainage Area Ratio & Surface of
Permanent Pool (Water Quality)
Table 1: Piedmont and Mountain SAIDA Table (Adapted from Driscoll, 1986)
10%
20%
0.51 0.43 0.37 0.30
0.84 IN 0.61 0.51
0.27 0.25
0.44 0.40
30%
1.17 081 0.84 072
061 0.56
40%
1.51 1.22 1.09 0-91
n.79 071
50%
1.70 1 47 1.31 1.13
0.95 087
W%
2.09 1.73 1.40 191
1.12 1.03
70%
2.51 2.04 180 1-66
1.34 1.17
W%
2.92 2.36 2.07 1.82
1.62 1.40
90%
3.25 2.64 2.31 2.04
1.84 1.59
Desired Depth =
3 ft
Imp. % Ratio
Lower Limit =
40.00 1.51
Upper Limit =
50.00 1.79
Minimum SA Required = 5,043 ft 2
Acutal =
48.62 1.75

Project Data
Revisions
Project #k
2018-002
No
Date
Description
Project Name
Kathryn's Retreat
1
8/30/2021
NCDENR Revisions
Date
10/6/2021
Wet Detention Pond 03
Total Main Pool
Stage Level
Elevation (ft)
Area (so
StageVolume
(co
Cumulative Storage
(co
0
252.5
2412
-
-
0.5
253
2658
1,268
1,268
1.5
254
3186
2,922
4,190
2.5
255
3762
3,474
7,664
3.5
256
4385
4,074
11,737
4.5
257
5057
4,721
16,458
5
257.5
5412
2,617
19,075
5.5
258
6536
2,987
22,062
Total Forebay Volume
Stage Level
Elevation (ft)
Area (sf)
Stage Volume
(co
Uumulative Storage
(co
0
255
389
-
-
1
256
804
597
597
2
257
1414
1,109
1,706
3
258
2030
1,722
3,428
Temporary Pool Volume
Stage Level
Elevation (ft)
Area (so
rage olume
(co
Cumulative Storage
(co
0
258
8566
-
-
0.5
258.5
10052
4,655
4,655
1
259
10995
5,262
9,916
1.25
259.25
12018
2,877
12,793
Average Depth Calculation:
VPP—Vsheif
D.O= Abottomofsheif
Where: D„,, = Average depth in feet
V- = Total volume of permanent pod (feet')
V,n,n = Volume over the shelf only (feel') — see below
A.—.~ = Area of wet pond at the bottom of the shelf (feet')
V.—= 0.5' Depth_a.,r—r' Perimeterp,,,,, * Wldth„e,.,,,� ,­
Where: D,,,,,,,,,,,,,,, = Depth of water at the deep side of the shelf as
measured at permanent pool (feet)
Petimeterp.,.,, - = Penmeter of permanent pool at the bottom of the
shelf (feet)
wAth,,,o,,--p,n a,na = Width from the deep side to the dry side of the
shelf as measured at permanent pool (feet)
Vsheif =
257 cf
Dma,—shelf =
0.5 ft
Pei meter =
343 ft
Width =
3 ft
Vpp = 22062 cf
Abe .f sh0f = 5412 sf
D®g = 4.03 ft

Per ject Data
Revisions
oject #
2018-002
No
Date
Description
oject Name
E
Kathryn's Retreat
te
10/6/2021
Wet Detention Pond #3
1) Input Orifice and Spillway Information
Orifice Diameter = 1.50 in
Office Coefficent = 0.60
Volume Provided = 12,793 cf
Number Orifices = 1.00
Inv Office = 258.00
Inv Primary Spillway = 259.25
2) Calculate Area, Head and Discharge Flow
Q = Co A 2gh
g= 32.2 ft/s2
h= use h/3 to simulate decreasing head
A= cross section area of orifice
Q= discharge cfs
Q= discharge cfs
Orfice Cross Section Area = 0.012 sf
Average head = 0.417 feet
Discharge = 0.038 cfs
3) Calculate Drawn Down Time
Time= Volume/Flowrate
Drawdown Time = 3.88 days
Check = OK

Per jest Data
Revisions
Project #
2018-002
No
Date
Description
Project Name
Kathryn's Retreat
Date
10/6/2021
Wet Detention Pond #3
DETERMINE BOUYANT FORCES
Volume = Depth * Area
Depth = Riser Top Elev - Riser Bottom Elev
Riser Top Elev. _
Bottom of Riser EIev. _
Riser Wall Thickness =
Diameter of Manhole =
Area = pi * diameter^2 / 4
Area (@ outside diam)=
Volume =
times wt of water
Bouyant Force =
2. DETERMINE COUNTERWEIGHT REQUIREMENTS
Riser Top
Top Elevation =
Thickness =
Outside Diam =
Volume =
Riser Walls
Inside Diam =
Wall Thickness =
Height =
Volume =
Riser Bottom - Extended Base
Bottom Elevation =
Diameter =
Thickness=
Volume =
Total Volume =
x unit weight of reinforced conc.
Counterweight =
Factor of Safety Provided (FSP) _
Additional Concrete Required (Y/N) _
Amount of Concrete Required =
3. ADD CONCRETE BELOW INVERT IN RISER
Area of Riser (@inside diam) _
Volume Required =
Calculated Depth of Concrete =
Actual Depth Used =
Backcheck Volume =
Backcheck Weight of Added Conc
(150-62.4) _
Factor of Safety =
Factor of Safety > 1.30 (Y/N) _
261 ft
257.50 ft
6.00 in
4.00 ft
19.64 sf
68.72 cf
62.4 Ibs/cf
4,288 Ibs
261
0 inches
5.00 ft
0.00 cf
4.00 ft
6.00 in
3.50 ft
24.74 cf
257.50
0.00 ft
6.00 in Summary
0.00 cf Add minimum 24 inches below invert of
pond
24.74 cf
150 Ibs/cf
3,711 Ibs
0.87
Y
1,864 Ibs
12.57 sf
21.28 cf
1.69 ft
24 in
25.13 cf
2202 lb
1.38
Y

CALCULATIONS & ANALYSIS
Hydraflow Routing
N
EST. 0 10

Hydraflow Table of Contents
Kathryns Retreate Phase 4 Routing.gpw
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Watershed Model Schematic...................................................................................... 1
Hydrograph Return Period Recap............................................................................. 2
2 - Year
SummaryReport.........................................................................................................................
3
HydrographReports
...................................................................................................................
4
Hydrograph No.
1, SCS Runoff, Pre -Development DA...........................................................
4
TR-55 Tc Worksheet...........................................................................................................
5
Hydrograph No.
3, SCS Runoff, Post -Development DA -
Bypass ............................................
6
TR-55 Tc Worksheet...........................................................................................................
7
Hydrograph No.
4, SCS Runoff, Post -Development DA -
SCM#1...........................................
8
Hydrograph No.
5, Reservoir, SCM#1 Outflow.........................................................................
9
PondReport
- Wet Pond#1...............................................................................................
10
Hydrograph No.
6, SCS Runoff, Post Development DA -
SCM#2..........................................
11
Hydrograph No.
7, Reservoir, SCM#2 Outflow.......................................................................
12
PondReport
- Wet Pond#2...............................................................................................
13
Hydrograph No.
8, SCS Runoff, Post -Development DA -
SCM#3.........................................
14
Hydrograph No.
9, Reservoir, SCM#3 Outflow.......................................................................
15
PondReport
- Wet Pond#3...............................................................................................
16
Hydrograph No.
10, Combine, Post -Development Total .......................................................
17
10 -Year
SummaryReport
.......................................................................................................................
18
HydrographReports.................................................................................................................
19
Hydrograph No.
1, SCS Runoff, Pre -Development DA.........................................................
19
Hydrograph No.
3, SCS Runoff, Post -Development DA - Bypass ..........................................
20
Hydrograph No.
4, SCS Runoff, Post -Development DA - SCM#1.........................................
21
Hydrograph No.
5, Reservoir, SCM#1 Outflow.......................................................................
22
Hydrograph No.
6, SCS Runoff, Post Development DA - SCM#2..........................................
23
Hydrograph No.
7, Reservoir, SCM#2 Outflow.......................................................................
24
Hydrograph No.
8, SCS Runoff, Post -Development DA - SCM#3.........................................
25
Hydrograph No.
9, Reservoir, SCM#3 Outflow.......................................................................
26
Hydrograph No.
10, Combine, Post -Development Total ........................................................
27
25 - Year
SummaryReport
.......................................................................................................................
28
HydrographReports.................................................................................................................
29
Hydrograph No.
1, SCS Runoff, Pre -Development DA.........................................................
29
Hydrograph No.
3, SCS Runoff, Post -Development DA - Bypass ..........................................
30
Hydrograph No.
4, SCS Runoff, Post -Development DA - SCM#1.........................................
31
Hydrograph No.
5, Reservoir, SCM#1 Outflow.......................................................................
32
Hydrograph No.
6, SCS Runoff, Post Development DA - SCM#2..........................................
33
Hydrograph No.
7, Reservoir, SCM#2 Outflow.......................................................................
34
Hydrograph No.
8, SCS Runoff, Post -Development DA - SCM#3.........................................
35
Hydrograph No.
9, Reservoir, SCM#3 Outflow.......................................................................
36
Hydrograph No.
10, Combine, Post -Development Total ........................................................
37
100 - Year

Contents continued...
Kathryns Retreate Phase 4 Routing.gpw
SummaryReport
.......................................................................................................................
38
HydrographReports.................................................................................................................
39
Hydrograph No.
1, SCS Runoff, Pre -Development DA.........................................................
39
Hydrograph No.
3, SCS Runoff, Post -Development DA - Bypass ..........................................
40
Hydrograph No.
4, SCS Runoff, Post -Development DA - SCM#1.........................................
41
Hydrograph No.
5, Reservoir, SCM#1 Outflow.......................................................................
42
Hydrograph No.
6, SCS Runoff, Post Development DA - SCM#2..........................................
43
Hydrograph No.
7, Reservoir, SCM#2 Outflow.......................................................................
44
Hydrograph No.
8, SCS Runoff, Post -Development DA - SCM#3.........................................
45
Hydrograph No.
9, Reservoir, SCM#3 Outflow.......................................................................
46
Hydrograph No.
10, Combine, Post -Development Total ........................................................
47
OFReport.................................................................................................................. 48

Watershed Model Schematic
1
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
CD
CD
ED
6
CD
8
CD
Legend
Hyd• Origin
Description
10
1 SCS Runoff
Pre -Development DA
3 SCS Runoff
Post -Development DA - Bypass
4 SCS Runoff
Post -Development DA - SCM#1
5 Reservoir
SCM#1 Outflow
6 SCS Runoff
Post Development DA - SCM#2
7 Reservoir
SCM#2 Outflow
8 SCS Runoff
Post -Development DA - SCM#3
9 Reservoir
SCM#3 Outflow
10 Combine
Post -Development Total
Project: Kathryns Retreate Phase 4 Routing.gpw
Wednesday, 04 / 7 / 2021

Hydrograph Return Period ReC"draflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd.
Hydrograph
Inflow
Peak Outflow (cfs)
Hydrograph
No.
type
hyd(s)
Description
(origin)
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
1
SCS Runoff
------
-------
31.98
-------
-------
95.52
141.74
-------
227.52
Pre -Development DA
3
SCS Runoff
------
-------
13.26
-------
-------
42.52
64.05
-------
104.28
Post -Development DA - Bypass
4
SCS Runoff
------
-------
15.67
-------
-------
27.90
35.62
-------
48.64
Post -Development DA - SCM#1
5
Reservoir
4
-------
2.103
-------
-------
8.484
21.17
-------
42.71
SCM#1 Outflow
6
SCS Runoff
------
-------
54.39
-------
-------
97.20
124.11
-------
169.54
Post Development DA - SCM#2
7
Reservoir
6
-------
6.044
-------
-------
17.69
70.97
-------
150.15
SCM#2 Outflow
8
SCS Runoff
------
-------
20.33
-------
-------
38.82
50.78
-------
71.32
Post -Development DA - SCM#3
9
Reservoir
8
-------
0.478
-------
-------
5.447
23.19
-------
60.77
SCM#3 Outflow
10
Combine
3, 5, 7,
-------
20.42
-------
-------
69.78
177.06
-------
355.86
Post -Development Total
9
Proj. file: Kathryns Retreate Phase 4 Routing.gpw
Wednesday, 04 / 7 / 2021

Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
31.98
1
726
116,438
------
------
------
Pre -Development DA
3
SCS Runoff
13.26
1
723
42,094
------
------
------
Post -Development DA - Bypass
4
SCS Runoff
15.67
1
718
31,885
------
------
------
Post -Development DA - SCM#1
5
Reservoir
2.103
1
732
26,096
4
259.29
15,439
SCM#1 Outflow
6
SCS Runoff
54.39
1
718
115,558
------
------
------
Post Development DA - SCM#2
7
Reservoir
6.044
1
743
95,433
6
257.08
57,534
SCM#2 Outflow
8
SCS Runoff
20.33
1
718
40,852
------
------
------
Post -Development DA - SCM#3
9
Reservoir
0.478
1
943
30,251
8
260.28
25,909
SCM#3 Outflow
10
Combine
20.42
1
724
193,874
3, 5, 7,
------
------
Post -Development Total
9
Kathryns Retreate Phase 4 Routing.gpw
Return Period: 2 Year
Wednesday, 04 / 7 / 2021

Hydrograph Report
4
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 1
Pre -Development DA
Hydrograph type
= SCS Runoff
Storm frequency
= 2 yrs
Time interval
= 1 min
Drainage area
= 45.600 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 3.70 in
Storm duration
= 24 hrs
Q (cfs
35.00
30.00
25.00
20.00
15.00
10.00
5.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Pre -Development DA
Hyd. No. 1 -- 2 Year
Wednesday, 04 / 7 / 2021
= 31.98 cfs
= 726 min
= 116,438 cuft
= 62
= 0 ft
= 18.10 min
= Type II
= 484
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
— Hyd No. 1 Time (min)

TR55 Tc Worksheet
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 1
Pre -Development DA
Description
A
B
C
Totals
Sheet Flow
Manning's n-value
= 0.240
0.011
0.011
Flow length (ft)
= 100.0
0.0
0.0
Two-year 24-hr precip. (in)
= 3.70
0.00
0.00
Land slope (%)
= 2.50
0.00
0.00
Travel Time (min)
= 12.14 +
0.00 +
0.00 =
12.14
Shallow Concentrated Flow
Flow length (ft)
= 583.00
0.00
0.00
Watercourse slope (%)
= 4.60
0.00
0.00
Surface description
= Unpaved
Paved
Paved
Average velocity (ft/s)
=3.46
0.00
0.00
Travel Time (min)
= 2.81 +
0.00 +
0.00 =
2.81
Channel Flow
X sectional flow area (sqft)
= 16.37
0.00
0.00
Wetted perimeter (ft)
= 12.47
0.00
0.00
Channel slope (%)
= 1.50
0.00
0.00
Manning's n-value
= 0.045
0.015
0.015
Velocity (ft/s)
=4.87
0.00
0.00
Flow length (ft)
q0})909.0
0.0
0.0
Travel Time (min)
= 3.11 +
0.00 +
0.00 =
3.11
Total Travel Time, Tc..............................................................................
18.10 min

Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 3
Post -Development DA
- Bypass
Hydrograph type
= SCS Runoff
Storm frequency
= 2 yrs
Time interval
= 1 min
Drainage area
= 19.000 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 3.70 in
Storm duration
= 24 hrs
Q (cfs)
14.00
12.00
10.00
ME
ME
4.00
2.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - Bypass
Hyd. No. 3 -- 2 Year
Wednesday, 04 / 7 / 2021
= 13.26 cfs
= 723 min
= 42,094 cuft
= 60
= 0 ft
= 13.10 min
= Type II
= 484
Q (cfs)
14.00
12.00
10.00
. ��
4.00
2.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

I
[I
TR55 Tc Worksheet
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 3
Post -Development DA - Bypass
Description
A
B
C
Totals
Sheet Flow
Manning's n-value
= 0.200
0.011
0.011
Flow length (ft)
= 100.0
0.0
0.0
Two-year 24-hr precip. (in)
= 3.70
0.00
0.00
Land slope (%)
= 5.00
0.00
0.00
Travel Time (min)
= 7.95 +
0.00 +
0.00 =
7.95
Shallow Concentrated Flow
Flow length (ft)
= 123.00
0.00
0.00
Watercourse slope (%)
= 0.50
0.00
0.00
Surface description
= Unpaved
Paved
Paved
Average velocity (ft/s)
=1.14
0.00
0.00
Travel Time (min)
= 1.80 +
0.00 +
0.00 =
1.80
Channel Flow
X sectional flow area (sqft)
= 16.37
0.00
0.00
Wetted perimeter (ft)
= 12.47
0.00
0.00
Channel slope (%)
= 1.50
0.00
0.00
Manning's n-value
= 0.045
0.015
0.015
Velocity (ft/s)
=4.87
0.00
0.00
Flow length (ft)
Q0})971.0
0.0
0.0
Travel Time (min)
= 3.33 +
0.00 +
0.00 =
3.33
Total Travel Time, Tc..............................................................................
13.10 min

Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 4
Post -Development DA
- SCM#1
Hydrograph type
= SCS Runoff
Storm frequency
= 2 yrs
Time interval
= 1 min
Drainage area
= 4.200 ac
Basin Slope
= 0.0 %
Tc method
= User
Total precip.
= 3.70 in
Storm duration
= 24 hrs
Q (cfs)
18.00
15.00
12.00
3.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - SCM#1
Hyd. No. 4 -- 2 Year
0.00
0 120 240 360 480 600 720
Hyd No. 4
Wednesday, 04 / 7 / 2021
= 15.67 cfs
= 718 min
= 31,885 cuft
= 83
= 0 ft
= 5.00 min
= Type II
= 484
Q (cfs)
18.00
15.00
12.00
3.00
' 0.00
840 960 1080 1200 1320 1440
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 5
SCM#1 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 2.103 cfs
Storm frequency
= 2 yrs
Time to peak
= 732 min
Time interval
= 1 min
Hyd. volume
= 26,096 cuft
Inflow hyd. No.
= 4 - Post -Development DA -
SCUM. Elevation
= 259.29 ft
Reservoir name
= Wet Pond #1
Max. Storage
= 15,439 cuft
Storage Indication method used.
Q (cfs)
18.00
15.00
12.00
3.00
0.00
0 300
Hyd No. 5
SCM#1 Outflow
Hyd. No. 5 -- 2 Year
Q (cfs)
18.00
15.00
12.00
3.00
0.00
900 1200 1500 1800 2100 2400 2700 3000
Time (min)
Hyd No. 4 0 Total storage used = 15,439 cuft

Pond Report
10
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Pond No. 1 - Wet Pond #1
Pond Data
Contours -User-defined contour areas.
Average end area method used for volume calculation.
Begining Elevation = 257.50 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sgft)
Incr. Storage (cult)
Total storage (cult)
0.00 257.50
6,653
0
0
0.50 258.00
7,922
3,644
3,644
1.00 258.50
8,734
4,164
7,808
1.50 259.00
9,720
4,614
12,421
2.50 260.00
10,952
10,336
22,757
3.50 261.00
12,242
11,597
34,354
4.00 261.50
12,907
6,287
40,642
Culvert / Orifice Structures
[A]
[B]
[C]
[PrfRsr]
Rise (in)
= 15.00
1.50
6.00
0.00
Span (in)
= 15.00
1.50
6.00
0.00
No. Barrels
= 1
1
4
0
Invert El. (ft)
= 257.50
257.50
258.75
0.00
Length (ft)
= 60.00
0.00
0.00
0.00
Slope (%)
= 1.00
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
0.60
0.60
Multi -Stage
= n/a
Yes
Yes
No
Stage (ft)
4.00
3.00
PAIIH
m
Weir Structures
[A]
[B]
[C]
[D]
Crest Len (ft)
= 15.71
30.00
0.00
0.00
Crest El. (ft)
= 259.75
260.50
0.00
0.00
Weir Coeff.
= 3.33
3.00
3.33
3.33
Weir Type
= 1
Rect
---
---
Multi-Stage
= Yes
No
No
No
Exfil.(in/hr)
= 0.000 (by
Contour)
TW Elev. (ft)
= 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage / Discharge
Elev (ft)
261.50
260.50
W-M%1111
258.50
0.00 T ' 257.50
0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0
Total Q Discharge (cfs)

11
Hydrograph
Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 6
Post Development DA - SCM#2
Hydrograph type
= SCS Runoff
Peak discharge
= 54.39 cfs
Storm frequency
= 2 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 115,558 cuft
Drainage area
= 16.100 ac
Curve number
= 83
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 7.00 min
Total precip.
= 3.70 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Post Development DA
- SCM#2
Q (cfs)
Hyd. No. 6 -- 2 Year
Q (cfs)
60.00
60.00
50.00 ' i i i i i 0 i i i i i i ' 50.00
40.00 ' ' 40.00
30.00 ' ' 30.00
20.00 ' "' ' 20.00
10.00 ' i i i i i ' " i i i i i i ' 10.00
0.00 1 1 1 1 1 1 1 1 1
' - - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
— Hyd No. 6 Time (min)

12
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 7
SCM#2 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 6.044 cfs
Storm frequency
= 2 yrs
Time to peak
= 743 min
Time interval
= 1 min
Hyd. volume
= 95,433 cuft
Inflow hyd. No.
= 6 - Post Development DA -
SCM#k Elevation
= 257.08 ft
Reservoir name
= Wet Pond #2
Max. Storage
= 57,534 cuft
Storage Indication method used.
SCM#2 Outflow
Q (cfs) Hyd. No. 7 -- 2 Year Q (cfs)
60.00 60.00
50.00 50.00
40.00 40.00
30.00 30.00
20.00 20.00
10.00 10.00
0.00 0.00
0 300 600 900 1200 1500 1800 2100 2400 2700 3000
Time (min)
— Hyd No. 7 Hyd No. 6 Total storage used = 57,534 cuft

Pond Report 13
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Pond No. 2 - Wet Pond #2
Pond Data
Contours -User-defined contour areas. Average end area method used for volume calculation. Begining Elevation = 254.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sgft)
Incr. Storage (cult)
Total storage (cult)
0.00 254.00
14,532
0
0
1.00 255.00
17,578
16,055
16,055
2.00 256.00
20,154
18,866
34,921
3.00 257.00
21,373
20,764
55,685
4.00 258.00
22,629
22,001
77,686
5.00 259.00
23,922
23,276
100,961
6.00 260.00
25,245
24,584
125,545
6.50 260.50
25,923
12,792
138,337
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A] [B]
[C] [D]
Rise (in) = 18.00
2.50
8.00
0.00
Crest Len (ft)
= 18.85 50.00
0.00 0.00
Span (in) = 18.00
2.50
8.00
0.00
Crest El. (ft)
= 258.00 259.30
0.00 0.00
No. Barrels = 1
1
4
0
Weir Coeff.
= 3.33 3.00
3.33 3.33
Invert El. (ft) = 254.00
254.00
256.00
0.00
Weir Type
= 1 Rect
--- ---
Length (ft) = 50.00
0.00
0.00
0.00
Multi -Stage
= Yes No
No No
Slope (%) = 1.00
0.00
0.00
n/a
N-Value = .013
.013
.013
n/a
Orifice Coeff. = 0.60
0.60
0.60
0.60
Exfil.(in/hr)
= 0.000 (by Contour)
Multi -Stage = n/a
Yes
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
7.00
6.00
5.00
4.00
3.00
2.00
WIDE
0.00
0.0 20.0
Total Q
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s)
40.0 60.0 80.0
Stage / Discharge
Elev (ft)
261.00
260.00
259.00
258.00
257.00
256.00
W-4&'111111111]
254.00
100.0 120.0 140.0 160.0 180.0 200.0 220.0
Discharge (cfs)

Hydrograph Report
14
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 8
Post -Development DA
- SCM#3
Hydrograph type
= SCS Runoff
Storm frequency
= 2 yrs
Time interval
= 1 min
Drainage area
= 6.610 ac
Basin Slope
= 0.0 %
Tc method
= User
Total precip.
= 3.70 in
Storm duration
= 24 hrs
Q (cfs)
21.00
18.00
15.00
12.00
• m
3.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - SCM#3
Hyd. No. 8 -- 2 Year
Wednesday, 04 / 7 / 2021
= 20.33 cfs
= 718 min
= 40,852 cuft
= 78
= 0 ft
= 5.00 min
= Type II
= 484
Q (cfs)
21.00
18.00
15.00
12.00
M
. 11
3.00
0.00 1 1 1 1 1 i..- ' 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 8 Time (min)

15
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 9
SCM#3 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 0.478 cfs
Storm frequency
= 2 yrs
Time to peak
= 943 min
Time interval
= 1 min
Hyd. volume
= 30,251 cuft
Inflow hyd. No.
= 8 - Post -Development DA -
SCUIAa Elevation
= 260.28 ft
Reservoir name
= Wet Pond #3
Max. Storage
= 25,909 cuft
Storage Indication method used.
Q (cfs
21.00
18.00
15.00
12.00
•m
. 11
3.00
SCM#3 Outflow
Hyd. No. 9 -- 2 Year
Q (cfs)
21.00
18.00
15.00
12.00
3.00
0.00 0.00
0 300 600 900 1200 1500 1800 2100 2400 2700 3000
Time (min)
Hyd No. 9 Hyd No. 8 0 Total storage used = 25,909 cuft

Pond Report
16
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Pond No. 3 - Wet Pond #3
Pond Data
Contours -User-defined contour areas.
Average end area method used for volume calculation.
Begining Elevation = 258.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sgft)
Incr. Storage (cult)
Total storage (cult)
0.00 258.00
8,566
0
0
0.50 258.50
10,052
4,655
4,655
1.00 259.00
10,995
5,262
9,916
2.00 260.00
13,203
12,099
22,015
3.00 261.00
14,831
14,017
36,032
4.00 262.00
16,517
15,674
51,706
5.00 263.00
18,259
17,388
69,094
Culvert / Orifice Structures
[A]
[B]
[C]
[PrfRsr]
Rise (in)
= 15.00
1.50
4.00
0.00
Span (in)
= 15.00
1.50
4.00
0.00
No. Barrels
= 1
1
1
0
Invert El. (ft)
= 257.50
258.00
259.25
0.00
Length (ft)
= 120.00
0.00
0.00
0.00
Slope (%)
= 0.50
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
0.60
0.60
Multi -Stage
= n/a
Yes
Yes
No
Stage (ft)
5.00
4.00
3.00
2.00
m
0.00
0.0 20.0
Total Q
Weir Structures
[A]
[B]
[C]
[D]
Crest Len (ft)
= 12.56
30.00
0.00
0.00
Crest El. (ft)
= 261.00
261.50
0.00
0.00
Weir Coeff.
= 3.00
3.33
3.33
3.33
Weir Type
= 1
Rect
---
---
Multi-Stage
= Yes
No
No
No
Exfil.(in/hr)
= 0.000 (by
Wet area)
TW Elev. (ft)
= 0.00
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s).
Stage / Discharge
40.0 60.0 80.0
Elev (ft)
263.00
262.00
261.00
260.00
259.00
258.00
100.0 120.0 140.0 160.0 180.0 200.0
Discharge (cfs)

17
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 10
Post -Development Total
Hydrograph type
= Combine
Peak discharge
= 20.42 cfs
Storm frequency
= 2 yrs
Time to peak
= 724 min
Time interval
= 1 min
Hyd. volume
= 193,874 cuft
Inflow hyds.
= 3, 5, 7, 9
Contrib. drain. area
= 19.000 ac
Post -Development Total
Q (cfs) Hyd. No. 10 -- 2 Year Q (cfs)
21.00 21.00
18.00 18.00
15.00 15.00
12.00 12.00
9.00 9.00
6.00 6.00
3.00 3.00
0.00 0.00
0 300 600 900 1200 1500 1800 2100 2400 2700 3000
Hyd No. 10 Hyd No. 3 Hyd No. 5 Hyd No. 7 Time (min)
Hyd No. 9

Hydrograph Summary Report
18
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
95.52
1
725
295,957
------
------
------
Pre -Development DA
3
SCS Runoff
42.52
1
722
112,191
------
------
------
Post -Development DA - Bypass
4
SCS Runoff
27.90
1
717
58,225
------
------
------
Post -Development DA - SCM#1
5
Reservoir
8.484
1
725
52,349
4
260.32
26,478
SCM#1 Outflow
6
SCS Runoff
97.20
1
718
211,023
------
------
------
Post Development DA - SCM#2
7
Reservoir
17.69
1
729
190,552
6
259.09
103,274
SCM#2 Outflow
8
SCS Runoff
38.82
1
718
79,442
------
------
------
Post -Development DA - SCM#3
9
Reservoir
5.447
1
730
67,495
8
261.25
39,998
SCM#3 Outflow
10
Combine
69.78
1
723
422,588
3, 5, 7,
------
------
Post -Development Total
9
Kathryns Retreate Phase 4 Routing.gpw
Return Period: 10 Year
Wednesday, 04 / 7 / 2021

Hydrograph Report
19
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 1
Pre -Development DA
Hydrograph type
= SCS Runoff
Storm frequency
= 10 yrs
Time interval
= 1 min
Drainage area
= 45.600 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 5.58 in
Storm duration
= 24 hrs
Q (cfs)
100.00
90.00
80.00
70.00
60.00
50.00
40.00
30.00
20.00
10.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Pre -Development DA
Hyd. No. 1 -- 10 Year
Wednesday, 04 / 7 / 2021
= 95.52 cfs
= 725 min
= 295,957 cuft
= 62
= 0 ft
= 18.10 min
= Type II
= 484
Q (cfs)
100.00
90.00
80.00
70.00
50.00
40.00
30.00
20.00
10.00
0.00 1 1 1 1 1 1— ' 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

Hydrograph Report
20
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 3
Post -Development DA
- Bypass
Hydrograph type
= SCS Runoff
Storm frequency
= 10 yrs
Time interval
= 1 min
Drainage area
= 19.000 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 5.58 in
Storm duration
= 24 hrs
Q (cfs)
50.00
40.00
30.00
20.00
10.00
0.00
0 120 240
Hyd No. 3
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - Bypass
Hyd. No. 3 -- 10 Year
360 480 600
Wednesday, 04 / 7 / 2021
= 42.52 cfs
= 722 min
= 112,191 cuft
= 60
= Oft
= 13.10 min
= Type II
= 484
Q (cfs)
50.00
40.00
30.00
20.00
10.00
0.00
720 840 960 1080 1200 1320 1440 1560
Time (min)

21
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 4
Post -Development DA
- SCM#1
Hydrograph type
= SCS Runoff
Peak discharge
= 27.90 cfs
Storm frequency
= 10 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 58,225 cuft
Drainage area
= 4.200 ac
Curve number
= 83
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 5.58 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Q (cfs)
28.00
24.00
20.00
16.00
12.00
Post -Development DA - SCM#1
Hyd. No. 4 -- 10 Year
Q (cfs)
28.00
24.00
20.00
16.00
12.00
: Me
4.00
0.00 1 1 1 1 1 1 1 1 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
— Hyd No. 4 Time (min)

22
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 5
SCM#1 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 8.484 cfs
Storm frequency
= 10 yrs
Time to peak
= 725 min
Time interval
= 1 min
Hyd. volume
= 52,349 cuft
Inflow hyd. No.
= 4 - Post -Development DA -
SCLWA. Elevation
= 260.32 ft
Reservoir name
= Wet Pond #1
Max. Storage
= 26,478 cuft
Storage Indication method used.
SCM#1 Outflow
Q (cfs) Hyd. No. 5 -- 10 Year Q (cfs)
28.00 28.00
24.00 24.00
20.00 20.00
16.00 16.00
12.00 12.00
8.00 8.00
4.00 4.00
0.00 - 0.00
0 180 360 540 720 900 1080 1260 1440 1620
Time (min)
Hyd No. 5 Hyd No. 4 Total storage used = 26,478 cuft

Hydrograph Report
23
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 6
Post Development DA -
SCM#2
Hydrograph type
= SCS Runoff
Storm frequency
= 10 yrs
Time interval
= 1 min
Drainage area
= 16.100 ac
Basin Slope
= 0.0 %
Tc method
= User
Total precip.
= 5.58 in
Storm duration
= 24 hrs
Q (cfs)
100.00
90.00
80.00
70.00
50.00
40.00
30.00
20.00
10.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Wednesday, 04 / 7 / 2021
= 97.20 cfs
= 718 min
= 211,023 cuft
= 83
= 0 ft
= 7.00 min
= Type II
= 484
Q (cfs)
100.00
90.00
80.00
70.00
50.00
40.00
30.00
20.00
10.00
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440
Hyd No. 6 Time (min)

24
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 7
SCM#2 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 17.69 cfs
Storm frequency
= 10 yrs
Time to peak
= 729 min
Time interval
= 1 min
Hyd. volume
= 190,552 cuft
Inflow hyd. No.
= 6 - Post Development DA -
SCM42 Elevation
= 259.09 ft
Reservoir name
= Wet Pond #2
Max. Storage
= 103,274 cuft
Storage Indication method used.
Q (cfs)
100.00
90.00
80.00
70.00
60.00
50.00
40.00
30.00
20.00
10.00
SCM#2 Outflow
Hyd. No. 7 -- 10 Year
Q (cfs)
100.00
90.00
80.00
70.00
50.00
40.00
30.00
20.00
10.00
0.00 0.00
0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880
Time (min)
Hyd No. 7 Hyd No. 6 0 Total storage used = 103,274 cuft

Hydrograph Report
25
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 8
Post -Development DA
- SCM#3
Hydrograph type
= SCS Runoff
Storm frequency
= 10 yrs
Time interval
= 1 min
Drainage area
= 6.610 ac
Basin Slope
= 0.0 %
Tc method
= User
Total precip.
= 5.58 in
Storm duration
= 24 hrs
Q (cfs)
40.00
30.00
10.00
0.00 1
0 120 240
— Hyd No. 8
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - SCM#3
Hyd. No. 8 -- 10 Year
360 480 600 720 840 960
Wednesday, 04 / 7 / 2021
= 38.82 cfs
= 718 min
= 79,442 cuft
= 78
= 0 ft
= 5.00 min
= Type II
= 484
Q (cfs)
40.00
30.00
20.00
10.00
0.00
1080 1200 1320 1440
Time (min)

Hydrograph
Report
26
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 9
SCM#3 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 5.447 cfs
Storm frequency
= 10 yrs
Time to peak
= 730 min
Time interval
= 1 min
Hyd. volume
= 67,495 cuft
Inflow hyd. No.
= 8 - Post -Development DA -
SCUIAa Elevation
= 261.25 ft
Reservoir name
= Wet Pond #3
Max. Storage
= 39,998 cuft
Storage Indication method used
Q (cfs)
40.00
30.00
10.00
SCM#3 Outflow
Hyd. No. 9 -- 10 Year
0.00
0 300 600 900 1200 1500 1800 2100 2400 2700
Hyd No. 9 Hyd No. 8 0 Total storage used = 39,998 cuft
Q (cfs)
40.00
30.00
20.00
10.00
0.00
3000
Time (min)

27
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 10
Post -Development Total
Hydrograph type
= Combine
Peak discharge
= 69.78 cfs
Storm frequency
= 10 yrs
Time to peak
= 723 min
Time interval
= 1 min
Hyd. volume
= 422,588 cuft
Inflow hyds.
= 3, 5, 7, 9
Contrib. drain. area
= 19.000 ac
Post -Development Total
Q (cfs) Hyd. No. 10 -- 10 Year Q (cfs)
70.00 70.00
60.00 60.00
50.00 50.00
40.00 40.00
30.00 30.00
20.00 20.00
10.00 10.00
0.00 0.00
0 180 360 540 720 900 1080 1260 1440 1620 1800
Hyd No. 10 Hyd No. 3 Hyd No. 5 Hyd No. 7 Time (min)
Hyd No. 9

Hydrograph Summary Report
28
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
141.74
1
724
428,548
------
------
------
Pre -Development DA
3
SCS Runoff
64.05
1
722
164,853
------
------
------
Post -Development DA - Bypass
4
SCS Runoff
35.62
1
717
75,346
------
------
------
Post -Development DA - SCM#1
5
Reservoir
21.17
1
722
69,436
4
260.76
31,530
SCM#1 Outflow
6
SCS Runoff
124.11
1
718
273,073
------
------
------
Post Development DA - SCM#2
7
Reservoir
70.97
1
723
252,479
6
259.79
120,443
SCM#2 Outflow
8
SCS Runoff
50.78
1
717
105,130
------
------
------
Post -Development DA - SCM#3
9
Reservoir
23.19
1
723
92,980
8
261.77
48,099
SCM#3 Outflow
10
Combine
177.06
1
723
579,747
3, 5, 7,
------
------
Post -Development Total
9
Kathryns Retreate Phase 4 Routing.gpw
Return Period: 25 Year
Wednesday, 04 / 7 / 2021

Hydrograph Report
29
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 1
Pre -Development DA
Hydrograph type
= SCS Runoff
Storm frequency
= 25 yrs
Time interval
= 1 min
Drainage area
= 45.600 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 6.75 in
Storm duration
= 24 hrs
Q (cfs
160.00
140.00
120.00
100.00
X1 11
F�
20.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Pre -Development DA
Hyd. No. 1 -- 25 Year
Wednesday, 04 / 7 / 2021
= 141.74 cfs
= 724 min
= 428,548 cuft
= 62
= 0 ft
= 18.10 min
= Type II
= 484
Q (cfs)
160.00
140.00
120.00
100.00
.1 91
E�
20.00
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
— Hyd No. 1 Time (min)

Hydrograph Report
30
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 3
Post -Development DA
- Bypass
Hydrograph type
= SCS Runoff
Storm frequency
= 25 yrs
Time interval
= 1 min
Drainage area
= 19.000 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 6.75 in
Storm duration
= 24 hrs
Q (cfs)
70.00
50.00
30.00
20.00
10.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - Bypass
Hyd. No. 3 -- 25 Year
Wednesday, 04 / 7 / 2021
= 64.05 cfs
= 722 min
= 164,853 cuft
= 60
= 0 ft
= 13.10 min
= Type II
= 484
Q (cfs)
70.00
50.00
40.00
30.00
20.00
10.00
0.00 1 1 1 1 1 1— ' _7111 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Time (min)

Hydrograph Report
31
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 4
Post -Development DA
- SCM#1
Hydrograph type
= SCS Runoff
Storm frequency
= 25 yrs
Time interval
= 1 min
Drainage area
= 4.200 ac
Basin Slope
= 0.0 %
Tc method
= User
Total precip.
= 6.75 in
Storm duration
= 24 hrs
Q (cfs)
40.00
30.00
10.00
0.00
0 120 240
— Hyd No. 4
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Post -Development DA - SCM#1
Hyd. No. 4 -- 25 Year
360 480 600 720 840 960
Wednesday, 04 / 7 / 2021
= 35.62 cfs
= 717 min
= 75,346 cuft
= 83
= 0 ft
= 5.00 min
= Type II
= 484
Q (cfs)
40.00
30.00
20.00
10.00
0.00
1080 1200 1320
Time (min)

Hydrograph
Report
32
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 5
SCM#1 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 21.17 cfs
Storm frequency
= 25 yrs
Time to peak
= 722 min
Time interval
= 1 min
Hyd. volume
= 69,436 cuft
Inflow hyd. No.
= 4 - Post -Development DA -
SCLWA. Elevation
= 260.76 ft
Reservoir name
= Wet Pond #1
Max. Storage
= 31,530 cuft
Storage Indication method used
SCM#1 Outflow
Q (cfs) Hyd. No. 5 -- 25 Year Q (cfs)
40.00 40.00
30.00 30.00
20.00 20.00
10.00 10.00
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
— Hyd No. 5 — Hyd No. 4 Total storage used = 31,530 cuft

33
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 6
Post Development DA -
SCM#2
Hydrograph type
= SCS Runoff
Peak discharge
= 124.11 cfs
Storm frequency
= 25 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 273,073 cuft
Drainage area
= 16.100 ac
Curve number
= 83
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 7.00 min
Total precip.
= 6.75 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Q (cfs)
140.00
120.00
100.00
Post Development DA - SCM#2
Hyd. No. 6 -- 25 Year
Q (cfs)
140.00
120.00
100.00
40.00
20.00
0.00 1 1 1 1 1 1 1 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
— Hyd No. 6 Time (min)

34
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 7
SCM#2 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 70.97 cfs
Storm frequency
= 25 yrs
Time to peak
= 723 min
Time interval
= 1 min
Hyd. volume
= 252,479 cuft
Inflow hyd. No.
= 6 - Post Development DA -
SCM#k Elevation
= 259.79 ft
Reservoir name
= Wet Pond #2
Max. Storage
= 120,443 cuft
Storage Indication method used.
Q (cfs
140.00
120.00
100.00
HIMITIN
SCM#2 Outflow
Hyd. No. 7 -- 25 Year
Q (cfs)
140.00
120.00
100.00
40.00
20.00
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
— Hyd No. 7 — Hyd No. 6 Total storage used = 120,443 cuft

35
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 8
Post -Development DA
- SCM#3
Hydrograph type
= SCS Runoff
Peak discharge
= 50.78 cfs
Storm frequency
= 25 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 105,130 cuft
Drainage area
= 6.610 ac
Curve number
= 78
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 6.75 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Q (cfs)
60.00
50.00
30.00
20.00
10.00
Post -Development DA - SCM#3
Hyd. No. 8 -- 25 Year
Q (cfs)
60.00
50.00
A
30.00
20.00
10.00
0.00 1 1 1 1'—I I I I 10.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
— Hyd No. 8 Time (min)

36
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 9
SCM#3 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 23.19 cfs
Storm frequency
= 25 yrs
Time to peak
= 723 min
Time interval
= 1 min
Hyd. volume
= 92,980 cuft
Inflow hyd. No.
= 8 - Post -Development DA -
SCUTAa Elevation
= 261.77 ft
Reservoir name
= Wet Pond #3
Max. Storage
= 48,099 cuft
Storage Indication method used.
Q (cfs)
60.00
50.00
30.00
20.00
10.00
0.00
0 240
— Hyd No. 9
SCM#3 Outflow
Hyd. No. 9 -- 25 Year
480 720 960
Hyd No. 8
Q (cfs)
60.00
50.00
VA�
30.00
20.00
10.00
0.00
1200 1440 1680 1920 2160
Time (min)
Total storage used = 48,099 cuft

37
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021 Wednesday, 04 / 7 / 2021
Hyd. No. 10
Post -Development Total
Hydrograph type = Combine Peak discharge = 177.06 cfs
Storm frequency = 25 yrs Time to peak = 723 min
Time interval = 1 min Hyd. volume = 579,747 cuft
Inflow hyds. = 3, 5, 7, 9 Contrib. drain. area = 19.000 ac
Q (cfs
180.00
150.00
120.00
30.00
Post -Development Total
Hyd. No. 10 -- 25 Year
\ L7
0.00
0 120 240
— Hyd No. 10
360 480 600
Hyd No. 3
Hyd No. 9
Q (cfs)
180.00
150.00
120.00
30.00
r.T.w
720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 5 Hyd No. 7

Hydrograph Summary Report
38
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
Peak
(min)
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
Description
1
SCS Runoff
227.52
1
724
675,954
------
------
------
Pre -Development DA
3
SCS Runoff
104.28
1
721
264,122
------
------
------
Post -Development DA - Bypass
4
SCS Runoff
48.64
1
717
104,975
------
------
------
Post -Development DA - SCM#1
5
Reservoir
42.71
1
720
99,032
4
261.01
34,503
SCM#1 Outflow
6
SCS Runoff
169.54
1
718
380,455
------
------
------
Post Development DA - SCM#2
7
Reservoir
150.15
1
720
359,714
6
260.21
130,939
SCM#2 Outflow
8
SCS Runoff
71.32
1
717
150,184
------
------
------
Post -Development DA - SCM#3
9
Reservoir
60.77
1
720
137,850
8
262.14
54,143
SCM#3 Outflow
10
Combine
355.86
1
720
860,718
3, 5, 7,
------
------
Post -Development Total
9
Kathryns Retreate Phase 4 Routing.gpw
Return Period: 100 Year
Wednesday, 04 / 7 / 2021

Hydrograph Report
39
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 1
Pre -Development DA
Hydrograph type
= SCS Runoff
Storm frequency
= 100 yrs
Time interval
= 1 min
Drainage area
= 45.600 ac
Basin Slope
= 0.0 %
Tc method
= TR55
Total precip.
= 8.73 in
Storm duration
= 24 hrs
Q (cfs
240.00
210.00
180.00
150.00
120.00
•It 11
30.00
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Pre -Development DA
Hyd. No. 1 -- 100 Year
Wednesday, 04 / 7 / 2021
= 227.52 cfs
= 724 min
= 675,954 cuft
= 62
= 0 ft
= 18.10 min
= Type II
= 484
Q (cfs)
240.00
210.00
180.00
150.00
120.00
•1 91
30.00
0.00 1 1 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
— Hyd No. 1 Time (min)

Hydrograph Report
40
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Hyd. No. 3
Post -Development DA - Bypass
Hydrograph type = SCS Runoff
Storm frequency = 100 yrs
Time interval = 1 min
Drainage area = 19.000 ac
Basin Slope = 0.0 %
Tc method = TR55
Total precip. = 8.73 in
Storm duration = 24 hrs
Peak discharge
Time to peak
Hyd. volume
Curve number
Hydraulic length
Time of conc. (Tc)
Distribution
Shape factor
Wednesday, 04 / 7 / 2021
= 104.28 cfs
= 721 min
= 264,122 cuft
= 60
= 0 ft
= 13.10 min
= Type II
= 484
Q (cfs)
120.00
Post -Development DA - Bypass
Hyd. No. 3 -- 100 Year
Q (cfs)
120.00
100.00
100.00
80.00
80.00
60.00
60.00
40.00
40.00
20.00
20.00
0.00
0 120 240 360 480 600 720 840
— Hyd No. 3
960 1080 1200
- 0.00
1320 1440 1560
Time (min)

41
Hydrograph
Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 4
Post -Development DA - SCM#1
Hydrograph type
= SCS Runoff
Peak discharge
= 48.64 cfs
Storm frequency
= 100 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 104,975 cuft
Drainage area
= 4.200 ac
Curve number
= 83
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 8.73 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Post -Development DA
- SCM#1
Q (cfs)
Hyd. No. 4 -- 100
Year
Q (cfs)
50.00
50.00
40.00 ' ' 40.00
30.00 ' ' 30.00
20.00 ' ' ' i i i ' 20.00
10.00 ' i i i i i ' " i i i ' 10.00
0.00 1- 0.00
0 120 240 360 480 600 720 840 960 1080 1200
Hyd No. 4 Time (min)

Hydrograph
Report
42
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 5
SCM#1 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 42.71 cfs
Storm frequency
= 100 yrs
Time to peak
= 720 min
Time interval
= 1 min
Hyd. volume
= 99,032 cuft
Inflow hyd. No.
= 4 - Post -Development DA -
SCUM. Elevation
= 261.01 ft
Reservoir name
= Wet Pond #1
Max. Storage
= 34,503 cuft
Storage Indication method used
SCM#1 Outflow
Q (cfs) Hyd. No. 5 -- 100 Year Q (cfs)
50.00 50.00
40.00 40.00
30.00 30.00
20.00 20.00
10.00 10.00
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440
Time (min)
Hyd No. 5 Hyd No. 4 0 Total storage used = 34,503 cuft

43
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 6
Post Development DA -
SCM#2
Hydrograph type
= SCS Runoff
Peak discharge
= 169.54 cfs
Storm frequency
= 100 yrs
Time to peak
= 718 min
Time interval
= 1 min
Hyd. volume
= 380,455 cuft
Drainage area
= 16.100 ac
Curve number
= 83
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 7.00 min
Total precip.
= 8.73 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Post Development DA - SCM#2
Q (cfs) Hyd. No. 6 -- 100 Year
180.00
160.00
140.00
120.00
100.00
60.00
40.00
20.00
Q (cfs)
180.00
160.00
140.00
120.00
100.00
60.00
40.00
20.00
0.00 1 1 1 1 1 1 1 1 10.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
— Hyd No. 6 Time (min)

44
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 7
SCM#2 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 150.15 cfs
Storm frequency
= 100 yrs
Time to peak
= 720 min
Time interval
= 1 min
Hyd. volume
= 359,714 cuft
Inflow hyd. No.
= 6 - Post Development DA -
SCM42 Elevation
= 260.21 ft
Reservoir name
= Wet Pond #2
Max. Storage
= 130,939 cuft
Storage Indication method used.
Q (cfs)
180.00
160.00
140.00
120.00
100.00
60.00
40.00
20.00
Q (cfs)
180.00
160.00
140.00
120.00
100.00
60.00
40.00
20.00
0.00 1 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 7 Hyd No. 6 0 Total storage used = 130,939 cuft

45
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 8
Post -Development DA
- SCM#3
Hydrograph type
= SCS Runoff
Peak discharge
= 71.32 cfs
Storm frequency
= 100 yrs
Time to peak
= 717 min
Time interval
= 1 min
Hyd. volume
= 150,184 cuft
Drainage area
= 6.610 ac
Curve number
= 78
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= User
Time of conc. (Tc)
= 5.00 min
Total precip.
= 8.73 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Q (cfs)
80.00
70.00
50.00
30.00
10.00
Post -Development DA - SCM#3
Hyd. No. 8 -- 100 Year
Q (cfs)
80.00
70.00
50.00
40.00
30.00
20.00
10.00
0.00 1 1 1 1 1 1 1 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
Hyd No. 8 Time (min)

46
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 9
SCM#3 Outflow
Hydrograph type
= Reservoir
Peak discharge
= 60.77 cfs
Storm frequency
= 100 yrs
Time to peak
= 720 min
Time interval
= 1 min
Hyd. volume
= 137,850 cuft
Inflow hyd. No.
= 8 - Post -Development DA -
SCUIAa Elevation
= 262.14 ft
Reservoir name
= Wet Pond #3
Max. Storage
= 54,143 cuft
Storage Indication method used.
SCM#3 Outflow
Q (cfs) Hyd. No. 9 -- 100 Year Q (cfs)
80.00 80.00
70.00 70.00
60.00 60.00
50.00 50.00
40.00 40.00
30.00 30.00
20.00 20.00
10.00 10.00
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 9 Hyd No. 8 0 Total storage used = 54,143 cuft

47
Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® by Autodesk, Inc. v2021
Wednesday, 04 / 7 / 2021
Hyd. No. 10
Post -Development Total
Hydrograph type
= Combine
Peak discharge
= 355.86 cfs
Storm frequency
= 100 yrs
Time to peak
= 720 min
Time interval
= 1 min
Hyd. volume
= 860,718 cuft
Inflow hyds.
= 3, 5, 7, 9
Contrib. drain. area
= 19.000 ac
Q (cfs
400.00
350.00
250.00
150.00
100.00
50.00
Post -Development Total
Hyd. No. 10 -- 100 Year
Q (cfs)
400.00
350.00
300.00
250.00
200.00
150.00
100.00
50.00
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 10 Hyd No. 3 Hyd No. 5 Hyd No. 7 Time (min)
Hyd No. 9

Hydraflow Rainfall Report
48
Hydraflow Hydrographs Extension for Autodesk0 Civil 3DO by Autodesk, Inc. v2021
Return
Period
Intensity -Duration -Frequency Equation Coefficients (FHA)
(Yrs)
B
D
E
(N/A)
1
57.0356
11.9000
0.8655
--------
2
69.0307
12.5000
0.8674
--------
3
0.0000
0.0000
0.0000
--------
5
69.4522
12.4000
0.8238
--------
10
68.8066
11.9000
0.7899
--------
25
64.1391
11.1000
0.7420
--------
50
58.2337
10.1000
0.6979
--------
100
53.8523
9.3000
0.6602
--------
File name: Raleigh.IDF
Intensity = B / (Tc + D)^E
Wednesday, 04 / 7 / 2021
Return
Period
Intensity Values (in/hr)
(Yrs)
5 min
10
15
20
25
30
35
40
45
50
55
60
1
4.94
3.94
3.30
2.85
2.51
2.25
2.04
1.87
1.73
1.61
1.50
1.41
2
5.76
4.64
3.89
3.37
2.98
2.67
2.42
2.22
2.05
1.91
1.79
1.68
3
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
5
6.60
5.36
4.54
3.96
3.52
3.17
2.89
2.66
2.47
2.31
2.16
2.04
10
7.38
6.01
5.11
4.47
3.98
3.60
3.29
3.04
2.83
2.65
2.49
2.35
25
8.16
6.68
5.70
5.01
4.48
4.07
3.74
3.46
3.23
3.03
2.86
2.71
50
8.76
7.17
6.14
5.41
4.86
4.43
4.08
3.79
3.55
3.34
3.16
3.00
100
9.30
7.63
6.55
5.79
5.22
4.77
4.41
4.11
3.85
3.64
3.45
3.28
Tc = time in minutes. Values may exceed 60.
Precip. file name: Z:WUtoCAD\Hydraflow\PCPWngier.pep
Storm
Rainfall Precipitation Table (in)
Distribution
1-yr
2-yr
3-yr
5-yr
10-yr
25-yr
50-yr
100-yr
SCS 24-hour
3.05
3.70
1.00
4.80
5.58
6.75
7.30
8.73
SCS 6-Hr
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff -1st
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-2nd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-3rd
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-4th
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Huff-Indy
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
Custom
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00

CALCULATIONS & ANALYSIS
Storm Sewer Composite C Values
N
EST. 0 10

Project Data
Revisions
roject#
2021-001
No
Date
Description
roject Name
rP
Kathryns Retreat - Phase 4
ate
4/7/2021
Storm Sewer System
Area (ac)
SpaceDrainage Open
•.
•.-
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
-----------
Table Value of RunnoffCoeifficients------
Open SpaceValue0.15 SF Residential 0.60
Woodlands 0.10 Open
Open------
------
------

CALCULATIONS & ANALYSIS
Hydraulic Grade Line
N
EST. 0 10

Hydraflow Storm Sewers Extension for Autodesk® Civil 3D® Plan
110
12
113
102 11 109
2 3 9
101 4 105
6 106 7
5 107
1 10 8
q
1g4 112 108
Outfall
111
Project File: KR 100 Series HGL.stm Number of lines: 13 Date: 4/7/2021
Storm Sewers v2021.00

MyReport
Page 1
Line
Inlet
Line
Drng
Runoff
Inlet
i
Flow
Invert
Invert
Gnd/Rim
Gnd/Rim
HGL
HGL
No.
ID
ID
Area
Coeff
Time
Inlet
Rate
Up
Dn
El Up
El Dn
Up
Dn
(ac)
(C)
(min)
(in/hr)
(cfs)
(ft)
(ft)
(ft)
(ft)
(ft)
(ft)
1
101
P676
0.12
0.60
5.0
7.44
13.91
259.00
258.00
264.25
259.79
260.34 j
260.00
2
102
P677
0.18
0.60
5.0
7.44
13.64
259.44
259.10
264.25
264.25
260.86
260.52
3
103
P677 (1)
0.21
0.80
5.0
7.44
13.19
260.07
259.54
266.46
264.25
261.64
261.37
4
104
P677 (1) (1)
0.13
0.64
5.0
7.44
6.33
262.16
260.57
268.28
266.46
263.13 j
262.05
5
105
P678
0.34
0.60
5.0
7.44
4.86
263.84
262.26
270.06
268.28
264.69 j
263.13
6
106
P679
0.32
0.60
5.0
7.44
2.85
264.93
264.04
271.15
270.06
265.61
264.69
7
107
P680
0.05
0.63
5.0
7.44
1.86
266.05
265.03
272.16
271.15
266.59 j
265.61
8
108
P682
0.01
0.95
5.0
7.44
0.07
266.42
266.15
272.16
272.16
266.52
266.59
9
113
P681
0.49
0.60
5.0
7.44
2.19
266.40
266.15
272.50
272.16
267.01
266.76
10
112
P683
0.31
0.60
5.0
7.44
1.38
264.11
264.04
270.06
270.06
264.73
264.69
11
109
P686
0.37
0.60
5.0
7.44
7.06
261.40
260.57
265.50
266.46
262.43 j
262.05
12
110
P687
1.60
0.60
10.0
6.07
5.83
264.00
261.50
268.00
265.50
264.98
262.43
13
111
P684
0.37
0.60
5.0
7.44
1.65
262.53
262.26
268.28
268.28
263.04
263.13
Project File: KR 100 Series HGL.stm
Number of lines: 13
Date: 4/7/2021
NOTES: Intensity = 73.48 / (Inlet time + 12.40) ^ 0.80 -- Return period = 10 Yrs. ; " Critical depth
Storm Sewers

Hydraulic Grade Line Computations
Page 1
Line
Size
Q
Downstream
Len
Upstream
Check
JL
Minor
coeff
loss
Invert
HGL
Depth
Area
Vel
Vel
EGL
Sf
Invert
HGL
Depth
Area
Vel
Vel
EGL
Sf
Ave
Enrgy
elev
elev
head
elev
elev
elev
head
elev
Sf
loss
(in)
WS)
(ft)
(ft)
(ft)
(sqft)
(ft/s)
(ft)
(ft)
N
(ft)
(ft)
(ft)
(ft)
(sgft)
(ft/s)
(ft)
(ft)
N
N
(ft)
(K)
(ft)
1
24
13.91
258.00
260.00
2.00
2.24
4.43
0.30
260.30
0.378
54.000
259.00
260.34 j
1.34"
2.24
6.21
0.60
260.94
0.604
0.491
n/a
0.94
n/a
2
24
13.64
259.10
260.52
1.42'
2.38
5.73
0.51
261.03
0.502
67.615
259.44
260.86
1.42
2.38
5.73
0.51
261.37
0.503
0.503
0.340
1.00
0.51
3
24
13.19
259.54
261.37
1.83
3.01
4.38
0.30
261.67
0.296
107.00
260.07
261.64
1.57
2.64
5.00
0.39
262.02
0.372
0.334
0.358
1.07
0.42
4
18
6.33
260.57
262.05
1.48
1.21
3.59
0.42
262.48
0.000
91.606
262.16
263.13 j
0.97"
1.21
5.23
0.42
263.56
0.000
0.000
n/a
1.32
n/a
5
18
4.86
262.26
263.13
0.87
1.03
4.57
0.35
263.48
0.000
176.51
263.84
264.69 j
0.85"
1.03
4.73
0.35
265.03
0.000
0.000
n/a
1.50
n/a
6
15
2.85
264.04
264.69
0.65
0.64
4.44
0.27
264.96
0.000
108.60
264.93
265.61
0.68"
0.68
4.19
0.27
265.88
0.000
0.000
n/a
0.50
0.14
7
15
1.86
265.03
265.61
0.58
0.51
3.35
0.21
265.81
0.000
101.63
266.05
266.59 j
0.54"
0.51
3.65
0.21
266.80
0.000
0.000
n/a
2.03
0.42
8
15
0.07
266.15
266.59
0.44
0.05
0.18
0.03
266.63
0.000
26.500
266.42
266.52
0.10"
0.05
1.49
0.03
266.56
0.000
0.000
n/a
1.00
0.03
9
15
2.19
266.15
266.76
0.61'
0.59
3.70
0.21
266.97
0.506
49.353
266.40
267.01
0.61
0.59
3.71
0.21
267.22
0.511
0.508
0.251
1.00
0.21
10
15
1.38
264.04
264.69
0.65
0.64
2.16
0.07
264.76
0.163
26.500
264.11
264.73
0.62
0.60
2.30
0.08
264.81
0.193
0.178
0.047
1.00
0.08
11
18
7.06
260.57
262.05
1.48
1.29
4.00
0.46
262.52
0.000
68.881
261.40
262.43 j
1.03"
1.29
5.47
0.46
262.89
0.000
0.000
n/a
0.50
n/a
12
15
5.83
261.50
262.43
0.93
0.98
5.97
0.50
262.93
0.000
137.43
264.00
264.98
0.98"
1.03
5.67
0.50
265.48
0.000
0.000
n/a
1.00
n/a
13
15
1.65
262.26
263.13
0.87
0.47
1.81
0.19
263.32
0.000
26.500
262.53
263.04
0.51 "
0.47
3.51
0.19
263.23
0.000
0.000
n/a
1.00
n/a
Project File: KR 100 Series HGL.stm
Number of lines: 13
Run Date: 4/7/2021
Notes: ' Normal depth assumed; " Critical depth.; j-Line contains hyd. jump c = cir e = ellip b = box
Storm Sewers v2021.00

Hydraflow Storm Sewers Extension for Autodesk® Civil 3D® Plan
Outfall
0
Project File: KR 200 Series HGL.stm I Number of lines: 1 1 Date: 4/7/2021
201
Storm Sewers v2021.00

MyReport
Page 1
Line
No.
Inlet
ID
Line
ID
Drng
Area
(ac)
Runoff
Coeff
(C)
Inlet
Time
(min)
i
Inlet
(in/hr)
Flow
Rate
(cfs)
Invert
Up
(ft)
Invert
Dn
(ft)
Gnd/Rim
El Up
(ft)
Gnd/Rim
El Dn
(ft)
HGL
Up
(ft)
HGL
Dn
(ft)
1
201
P685
1.09
0.60
10.0
6.07
3.97
259.91
258.00
264.25
259.52
260.72 j
259.25
Project File: KR 200 Series HGL.stm
Number of lines: 1
Date: 4/7/2021
NOTES: Intensity = 73.48 / (Inlet time + 12.40) ^ 0.80 -- Return period = 10 Yrs. ; " Critical depth
Storm Sewers

Hydraulic Grade Line Computations
Page 1
Line
Size
Q
Downstream
Len
Upstream
Check
JL
Minor
coeff
loss
Invert
HGL
Depth
Area
Vel
Vel
EGL
Sf
Invert
HGL
Depth
Area
Vel
Vel
EGL
Sf
Ave
Enrgy
elev
elev
head
elev
elev
elev
head
elev
Sf
loss
(in)
WS)
(ft)
(ft)
(ft)
(sqft)
(ft/s)
(ft)
(ft)
N
(ft)
(ft)
(ft)
(ft)
(sgft)
(ft/s)
(ft)
(ft)
N
N
(ft)
(K)
(ft)
1
15
3.97
258.00
259.25
1.25
0.84
3.24
0.16
259.41
0.378
23.918
259.91
260.72 j
0.81 "
0.84
4.75
0.35
261.07
0.677
0.528
n/a
1.00
n/a
Project File: KR 200 Series HGL.stm
Number of lines: 1
Run Date: 4/7/2021
Notes: ; " Critical depth.; j-Line contains hyd. jump ; c = cir e = ellip b = box
Storm Sewers v2021.00

CALCULATIONS & ANALYSIS
Gutter Spread
N
EST. 0 10

Hydraflow Storm Sewers Extension for Autodesk® Civil 3D® Plan
110
12
1
102 11 109
2 3
9
105
6 106 7
101 4 5 107
1 10 8
��4 112 108
111
Project File: KR 100 Series GUTTER.stm Number of lines: 13 Date: 4/7/2021
Storm Sewers v2021.00

Gutter
Page 1
Line
Inlet
Drng
Inlet
i
Runoff
Flow
Q
Q
Q
Curb
Grate
Grate
Grate
Gutter
Gutter
Cross
Inlet
Gutter
Gutter
Byp
No.
ID
Area
Time
Inlet
Coeff
Rate
Capt
Carry
Byp
Len
Len
Width
Area
Slope
Width
SI, Sx
Depth
Depth
Spread
Ln No
(ac)
(min)
(in/hr)
(C)
(cfs)
(cfs)
(cfs)
(cfs)
(ft)
(ft)
(ft)
(sgft)
(ft/ft)
(ft)
(ft/ft)
(ft)
(ft)
(ft)
(ft)
1
101
0.12
5.0
4.00
0.60
8.63
0.29
0.00
0.00
....
3.00
2.00
6.00
Sag
2.00
0.020
0.05
n/a
0.05
6.51
Sag
Yard Inlet
2
102
0.18
5.0
4.00
0.60
8.43
0.43
0.00
0.00
....
3.00
2.00
6.00
Sag
2.00
0.020
0.06
n/a
0.06
7.91
Sag
Yard Inlet
3
103
0.21
5.0
4.00
0.80
8.13
0.94
0.27
0.00
3.00
3.00
2.00
6.00
Sag
2.00
0.020
0.17
n/a
0.17
6.31
Sag
4
104
0.13
5.0
4.00
0.64
3.88
0.47
0.19
0.05
3.00
3.00
2.00
....
0.010
2.00
0.020
0.13
0.06
0.13
4.58
3
5
105
0.34
5.0
4.00
0.60
2.95
0.75
0.13
0.19
3.00
3.00
2.00
....
0.010
2.00
0.020
0.16
0.09
0.16
6.01
4
6
106
0.32
5.0
4.00
0.60
1.71
0.64
0.00
0.13
3.00
3.00
2.00
....
0.010
2.00
0.020
0.15
0.08
0.15
5.49
5
7
107
0.05
5.0
4.00
0.63
1.11
0.13
0.00
0.00
3.00
3.00
2.00
....
0.010
2.00
0.020
0.08
0.00
0.08
1.99
6
8
108
0.01
5.0
4.00
0.95
0.04
0.04
0.00
0.00
3.00
3.00
2.00
....
0.010
2.00
0.020
0.05
0.00
0.05
1.27
10
9
113
0.49
5.0
4.00
0.60
1.18
1.18
0.00
0.00
....
3.00
2.00
6.00
Sag
2.00
0.020
0.12
n/a
0.12
13.53
Sag
Yard Inlet
10
112
0.31
5.0
4.00
0.60
0.74
0.62
0.00
0.12
3.00
3.00
2.00
....
0.010
2.00
0.020
0.15
0.08
0.15
5.41
13
11
109
0.37
5.0
4.00
0.60
4.32
0.89
0.00
0.00
....
3.00
2.00
6.00
Sag
2.00
0.020
0.10
n/a
0.10
11.56
Sag
Yard Inlet
12
110
1.60
10.0
3.70
0.60
3.55
3.55
0.00
0.00
....
3.00
2.00
6.00
Sag
2.00
0.020
0.24
n/a
0.24
26.08
Sag
Yard Inlet
13
111
0.37
5.0
4.00
0.60
0.89
0.79
0.12
0.21
3.00
3.00
2.00
....
0.010
2.00
0.020
0.16
0.10
0.16
6.19
3
Project File: KR 100 Series GUTTER.stm
Number of lines: 13
Date: 4/7/2021
NOTES: Intensity = 11.82 / (Inlet time + 15.40) ^ 0.36 -- Return period = 1 Yrs. ; " Critical depth
Storm Sewers

CALCULATIONS
Outlet Protection
N
EST. 0 10
o?�

Project Data
Rovisi
Project #
2021-001
No
Date
Description
Project Name
Kathryns Retreat Phase 4
Date
4/7/2021
Defined Channel (Y/N)
N
Diameter (in)
24
Flow Rate (cfs)
13.91
Slope (%)
1.87
Mannino Coef.
0.013
nal Depth (ft) 0.94
et Velocity (fps) 9.60
z
2i
t
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um
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omarrrmmr� ®�Q
4r�6�1Qm►"®�Q�rO►��
r
DIAMETER (Ft.)
Zone = 2
iliiii■iiii
FES#100
Diagram of Outlet Appron
LENGTH OF APRON
TO PROTECT
TO PREVENT SCO DR
W
APRON MATERIAL
c:
n
CULVERT
HOLE USE L2ALWAYS
L2
Li
1
STONE FILLING (FINE) CL. A
3 x D�
4 x D.
2
STONE FILLING (LIGHT) GL_ B
3 X D�
6 x D
3
STONE FILLING (MEDIUM) GL. 1
4 X D�
6 x Do
4
STONE FILLING (HEAVY) CL. 1
4 X D�
6 x Do
5
STONE FILLING (HEAVY) CL_ 2
5 x D�
10 x Ea
6
STONE FILLING (HEAVY) CL_ 2
6 X D�
10 x Dq
J SPECIAL STUDY REQUIRED (ENERGY DISSIPATORS, STILLING
BASIN OR LARGER SIZE STONE).
Classification
Average
Diameter (in)
Stone Class
Minimum
Thickness (in)
Fine
3
A
12
Light
6
B
18
Medium
13
1
24
Heavy
1 23
1 2
36
Equations
Summary
L = See Table
Length of Apron =
12 ft
W, = 3 x Diameter
Width at Pipe, W, =
6 ft
Width at end of Apron, W2 =
W2 = Diameter + 0.4*L
(defined channel)
N/A ft
Width at end of Apron, W2 =
W2 = 1.25 X W,
(undefined channel)
8 ft
Classification =
LIGHT
NCDOT Stone Class =
B
Min. Thickness=
18 in

Projeot Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryns Retreat Phase 4
Date
4/7/2021
Defined Channel (Y/N)
N
Diameter (in)
15
Flow Rate (cfs)
3.97
Slope (%)
8.00
Mannino Coef.
0.013
nal Depth (ft) 0.40
et Velocity (fps) 16.69
t
rrrrrr
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ur,lrnrra
S70
i
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7
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wAn
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rrarr.�•®rpPmIP�1101
-
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ro
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rrr.
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MIN
MIN
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m��rr®aa1®>�Or��VO®
m
ry
inw rmM 1M ®�0 Igrr06�i�"®�Q�rO►��
r
®
Zone = 3
Equations
L = See Table
W, = 3 x Diameter
W2 = Diameter + 0.4*L
W2=1.25XW,
FES#200
Diagram of Outlet Appron
LENGTH OF APRON
TO PROTECT
TO PREVENT SCO DR
W
APRON MATERIAL
c:
n
CULVERT
HOLE USE L2ALWAYS
L2
Li
1
STONE FILLING (FINE) CL. A
3 x D�
4 x D.
2
STONE FILLING (LIGHT) GL_ B
3 X D�
6 x D
3
STONE FILLING (MEDIUM) GL. 1
4 X D�
8 x Do
4
STONE FILLING (HEAVY) CL. 1
4 X D�
6 x Do
5
STONE FILLING (HEAVY) CL_ 2
5 x D�
10 x Ea
6
STONE FILLING (HEAVY) CL_ 27
6 X D�
10 x Dq
7 SPECIAL STUDY REQUIRED (ENERGY DISSIPATORS, STILLING
BASIN OR LARGER SIZE STONE).
Classification
Average
Diameter (in)
Stone Class
Minimum
Thickness (in)
Fine
3
A
12
Light
6
B
18
Medium
13
1
24
Heavy
23
2
36
Summary
Length of Apron =
10
ft
Width at Pipe, W, =
4
ft
Width at end of Apron, W2 =
(defined channel)
N/A
ft
Width at end of Apron, W2 =
(undefined channel)
5
ft
Classification =
MEDIUM
NCDOT Stone Class =
1
Min. Thickness=
24
in

Project Data
Revisions
Project #
2021-001
No
Date
Description
Project Name
Kathryns Retreat Phase 4
Date
4/7/2021
Defined Channel (Y/N)
N
Diameter (in)
15
Flow Rate (cfs)
5.45
Slope (%)
0.63
Mannino Coef.
0.013
nal Depth (ft) 0.99
et Velocity (fps) 3.86
z
2i
t
rrrrrr
w�ows.rruumrm
ur�rnrra
S70
i
-
®rrnrawr
err®o�onFji
�awrrrr�rnmr-®
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r�®n�vm�-ten®
arQmm�a�vrrrs�w
�aosrr►�`�mdd�o®
rrw»rarr®.
osi
mm�rim�w� Omar
ardrrrrr.�ro�m
�os•avr�v�-vn��rr�u®
o
raQ
mo'��mr��arrv��ed�r
®n�mvs�m��m-�mrr�a®
m
1ri� rm�6V r�1r��YQrr
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®�0
1rr�6�1��"®�Q�rO►��
r
LJWNIC ICI kr L.)
Zone = 2 <-- Use 2 Minimum
iliiii■iiii
FES#300
Diagram of Outlet Appron
LENGTH OF APRON
TO PROTECT
TO PREVENT SCO DR
W
APRON MATERIAL
c:
n
CULVERT
HOLE USE L2ALWAYS
L2
Li
1
STONE FILLING (FINE) CL. A
3 x D�
4 x D.
2
STONE FILLING (LIGHT) GL- B
3 X D�
6 x D
3
STONE FILLING (MEDIUM) GL. 1
4 X D�
6 x Do
4
STONE FILLING (HEAVY) CL. 1
4 X D�
6 x Do
5
STONE FILLING (HEAVY) CL- 2
5 x D�
10 x Ea
6
STONE FILLING (HEAVY) CL- 2
6 X D�
10 x Dq
7 SPECIAL STUDY REQUIRED (ENERGY DISSIPATORS, STILLING
BASIN OR LARGER SIZE STONE).
Classification
Average
Diameter (in)
Stone Class
Minimum
Thickness (in)
Fine
3
A
12
Light
6
B
18
Medium
13
1
24
Heavy
23
2
36
Equations
Summary
L = See Table
Length of Apron =
16 ft
W, = 3 x Diameter
Width at Pipe, W, =
8 ft
Width at end of Apron, W2 =
W2 = Diameter + 0.4*L
(defined channel)
N/A ft
Width at end of Apron, W2 =
W2 = 1.25 X W,
(undefined channel)
10 ft
Classification =
LIGHT
NCDOT Stone Class =
B
Min. Thickness=
18 in

CALCULATIONS
Temporary Ditch Calculations
EST. 0 10
o?�

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryns Retreat Phase 4
Date
4/7/2021
Peak Discharge Calculation (10 Year Design)
Drainage Area 4.28 ac
C = 0.50 Bare Earth
I10 = 7.91 in/hr Assume Tc =5 min
A = 4.28 ac
Q10= 16.93 cfs
Determine Ditch Flow Depth (d) and Velocity (v) - Check for Temporary Conditions
Apply Manning's Equation: V=Z49/n *R2/3*S1/2, Q=A/V
Ditch Characteristics:
n = 0.02 Bare Earth
Base Width (B) = 1.50 ft
M= 3
Ditch Slope (S) = 1.30% M:1 rc
Permissible Max Velocity (Vp) = 2.00 fps
FBI
Apply the Following Analysis to Determine Actual "d"and 'Y'
d = flow depth = 0.82 ft
Area (A) = B*d + M*d2 = 3.24
Perimeter (P) = b + 2d*(M2+1).5 = 6.68
R = A/P = 0.48
VpR = V Permiss * R = 0.97
V = Flow Velocity = 5.23 fps
Q = design flow = 16.93 cfs check Q: OK
Check Ditch Velocity for Lining:
VP = 2.00 fps Vactual>Vallow, Find
Temp Lining
Vactual = 5.23 fps
Determine Temporary Liner
Recalculate with Liner:
Liner Material = Straw with Net Tshear
51e55 = Shear stress =
g*d*s
n = 0.033 Table 8.05e NCESCPDM
g = density of water =
62.4 Ib/ft3
Base Width (B) = 1.50 ft
d = flow depth =
1.03 ft
M = 3
S = channel slope =
1.30%
Ditch Slope (S) = 1.30% Tshear
stress = Shear Stress =
0.83
T allow (Td) = 1.45 psf Compare
Tshear stress to To. -
Apply the Following Analysis to Determine Actual "d" and 'Y'
T al low (Td)
1.45
d = flow depth = 1.03 ft
Tshear stress =
0.83
Area (A) = B*d + M*d2 = 4.69
Perimeter (P) = b + 2d*(M2+1).5 = 7.99
Tshear stress < Td => OK
R = A/P = 0.59
V = Flow Velocity = 3.61 fps
Summary
Q = design flow = 16.93 cfs check Q: OK
Temporary Ditch Loner e
Straw with Net

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryns Retreat Phase 4
Date
4/7/2021
TDD B
Peak Discharge Calculation (10 Year Design)
Drainage Area 1.1 ac
C = 0.50 Bare Earth
I10 = 7.91 in/hr Assume Tc =5 min
A= 1.10 ac
Q10= 4.35 cfs
Determine Ditch Flow Depth (d) and Velocity (v) - Check for Temporary Conditions
Apply Manning's Equation: V=Z49/n *R2/3*S1/2, Q=A/V
Ditch Characteristics:
n = 0.02 Bare Earth
Base Width (B) = 1.50 ft
M= 2
Ditch Slope (S) = 1.20% M:1
Permissible Max Velocity (Vp) = 2.00 fps
FBI
Apply the Following Analysis to Determine Actual "d"and 'Y'
d = flow depth = 0.47 ft
Area (A) = B*d + M*d2 = 1.15
Perimeter (P) = b + 2d*(M2+1).5 = 3.60
R = A/P = 0.32
VpR = V Permiss * R = 0.64
V = Flow Velocity = 3.79 fps
Q = design flow = 4.35 cfs check Q: OK
Check Ditch Velocity for Lining:
VP = 2.00 fps Vactual>Vallow, Find
Temp Lining
Vactual = 3.79 fps
Determine Temporary Liner
Recalculate with Liner:
Liner Material = Jute Net Tshear
51e55 = Shear stress =
g*d*s
n = 0.022 Table 8.05e NCESCPDM
g = density of water =
62.4 Ib/ft3
Base Width (B) = 1.50 ft
d = flow depth =
0.53 ft
M = 2
S = channel slope =
1.20%
Ditch Slope (S) = 1.20% Tshear
stress = Shear Stress =
0.39
T allow (Td) = 0.45 psf Compare
Tshear stress to To. -
Apply the Following Analysis to Determine Actual "d" and 'Y'
T al low (Td)
0.45
d = flow depth = 0.53 ft
Tshear stress =
0.39
Area (A) = B*d + M*d2 = 1.35
Perimeter (P) = b + 2d*(M2+1).5 = 3.86
Tshear stress < Td => OK
R = A/P = 0.35
V = Flow Velocity = 3.66 fps
Summary
Q = design flow = 4.93 cfs check Q: FixQ
Temporary Ditch Loner e
Jute Net

CALCULATIONS
Sediment Basin Calculations
EST. 0 10
o?�

Project Data
Revisions
Project#
2021-001
No
Date
Description
Project Name
Kathryn's Retreat Phase 4
Date
4/7/2021
Skimmer Basin 01
Sediment Basin # 1
Area Disturbed = 287931.6 sf
6.61 acres
Peak Discharge Calculation:
Drainage Area = 287932 sf
Composite C
6.61 acres
C A (ac)
C*A
Woods/Open 0.15 0.00
0.00
QIo = C x I x A
Bare Earth 0.50 0.00
0.00
C = 0.50
Ex. Impery 0.50 0.00
0.00
I10= 7.44 in/hr
A = 6.61 acres
Composite Value =
0.00
010 = 24.59 cfs
Minimum Surface Area Calculation:
Surface Area (SF) = Q10 x 435 sf/ac
= 24.59 cfs x 435 sf/ac
Surface Area Req = 10696 sf
Basin Volume Calculation:
Volume of Sediment = (Drainage Ac.) x (1800 cf sed./year) x (1 year)
= 6.61 ac x 1800 x 1 yr
Min Vol = 11898 cf
Assumed basin depth = 2 ft
min D = 2' for "Temp Sediment
Trap"
Resultant Basin Area Req = 5949 sf
Check Surface Area Criteria
Surface Area Requirement = 10696 sf
Basin Volume Calc Area = 5949 sf
Therefore: Surface Area Governs
Min Volume Req = 11898 cf
Min Area Req = 10696 sf
L:WRatio = 2.5
Use L=2.5xW, calculate basin dimensions
Actual W = 65 ft
Min W = 66
ft
L= 165 ft
Min = 165
ft
D = 2 ft
Actual Vol = 21450 cf
Vol Check: OK
Actual Area = 10725 sf
Area Check: OK
Actual Basin Dimensions = 65 ft W x 165 ft L x 2 ft
Weir Design and Velocity Check:
Calculate Flow Depth H = [Q/CL]2i3
Q10 = 24.59 cfs
C = 2.68 constant
L= 30 ft
min L=10'
H= 0.45 ft
max H=0.5'
Calculate Velocity Over Weir V = Q/A
V = 24.59 cfs / 30 ft x 0.45 ft
V = 1.81 ft/sec
OK
Skimmer Sizing:
4 Skimmer Size (inches)
Skimmer Size
0.333 Head on Skimmer (feet)
(Inches)
1.5
2.5 Orifice Size (1/4 inch increments)
2.57 Dewatering Time (days)
2
2.5
3
��d6