SW6200904_Report (Stormwater)_20210312

Storm water Management Report
March 12, 2021
Timberland Ranch
Calloway Road
Hoke County, NC
14
Prepared for:
Double D Engineering, PLLC
150 S. Page Street
Southern Pines, NC 28387
910-684-8646
Prepared by:
Triangle Site Design, PLLC
4004 Barrett Drive, Suite 101
Raleigh, NC 27609
[phone]
License#P-0619
TRIANGLE
SITE D E S I G N

TABLE OF CONTENTS
OVERVIEW
FIGURES
SOILS SURVEY & SOIL INFORMATION
USGS TOPOGRAPHIC MAP
FEMA FIRM MAP
WATER SURFACE CLASSIFICATIONS
HUC
NOAA POINT PRECIPITATION FREQUENCY ESTIMATES
WATER QUANTITY -INFILTRATION TRENCH #1
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION TRENCH #2
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION TRENCH #3
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION

WATER QUANTITY -INFILTRATION TRENCH #4
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION TRENCH #5
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION TRENCH #6
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION TRENCH #7
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION

WATER QUANTITY -INFILTRATION TRENCH #8
DRAINAGE AREA MAP
CN VALUES
PRE -DEVELOPMENT HYDROGRAPHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME -FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION

OVERVIEW
This report contains the storm water management overview for the proposed residential
development Timberland Ranch on Calloway Road in Hoke County. The project site is
currently un—developed. The proposed site consists of 524.7 acres and approximately
13.36 acres will be disturbed as part of this project for the construction of the site
improvements.
The proposed site is located in Flood Zone `X' as shown on FEMA FIRM Panel 3710940600J
with an effective date of 10/17/06 and Panel 3710940400J with an effective date of
10/17/06. Flood zones are subject to change by FEMA.
There are no existing stream or wetland features on the proposed property.
The proposed site satisfies a Low Density Project as a Phase II tipped county designation in
Hoke County. The development of the site will result in an impervious area of 1,010,543sf
(23.20ac - 4.43% impervious). The BUA is less than the 24% threshold and there are less
than two dwelling units/acre. Therefore, no Stormwater Control measures are required for the
project site. However, in order for the post —developed stormwater runoff to not exceed the
pre —developed stormwater runoff to the NCDOT roadway, infiltration trenches have been
designed for post —development peak attenuation only. There are eight infiltration trenches
throughout the site that are designed to provide peak flow attenuation for the 1, 2 & 10 year
storm events. In addition, in exchange for limiting the BUA, dispersed flow will be maximized
and stormwater conveyances will be vegetated.

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Impervious Area - Infiltration Trench #i
Lots 6 000sf/lot x 14 lots
840001
1.93
Road
24767
0.57
Sidewalk
47021
0.11
Total
1134691
2.61
Impervious Area - Infiltration Trench #2
Lots 6 000sf/lot x 6 lots
360001
0.83
Road
11589
0.27
Sidewalk
13441
0.03
Total
489331
1.12
Impervious Area - Infiltration Trench #3
Lots 12 000sf/lot x 6 lots
720001
1.65
Road
1 97501
0.22
Total
1 817501
1.88
Impervious Area - Infiltration Trench #4
Lots 12 000sf/lot x 8 lots
960001
2.20
Road
15796
0.36
Mail Kiosk
53451
0.12
Total
117141
2.69
Impervious Area - Infiltration Trench #5
Lots 12 000sf/lot x 6 lots
720001
1.65
Road
1 96981
0.22
Total
1 816981
1.88
Impervious Area - Infiltration Trench #6
Lots 12 000sf/lot x 2 lots)
24000
0.55
Total
1 240001
0.55
Im pervious Area - Infiltration Trench A
Lots 15,000sf/lot x 8 lots
1200001
2.75
Road
1 140331
0.32
Total
1340331
3.08
Impervious Area - Infiltration Trench #8
Lots 15 000sfilot x 10 lots
1500001
3.44
Road
1 170801
0.39
Total
1 167080
3.84

FIGURES

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Hydrologic Soil Group —Hoke County, North Carolina
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
AuA Autryville loamy sand, 0 A 3.9 3.4%
to 2 percent slopes
CaB Candor sand. 1 to S A 110.3 94.9%
percent slopes
F3a Rains sandy loam, 0 to A/D 2.0 1.7%
2 percent slopes
Totals for Area of Interest 116.2 100.0%
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive
precipitation from long -duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when
thoroughly wet. These consist mainly of deep, well drained to excessively
drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well
drained soils that have moderately fine texture to moderately coarse texture.
These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of
water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink -swell
potential, soils that have a high water table, soils that have a claypan or clay
layer at or near the surface, and soils that are shallow over nearly impervious
material. These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in
their natural condition are in group D are assigned to dual classes.
USDA Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
1 /11/2021
Page 3 of 4

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:ream :nde:
18-31-11
Stream Neme
M II Creek
Descr peon
From source to
Rockfish Creek
Cless LcaTon
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August 31 1474
A'haT does tF. s C �eas
mean
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1/11/2021 Precipitation Frequency Data Server
NOAA Atlas 14, Volume 2, Version 3
Location name: Raeford, North Carolina, USA*
Latitude: 35.0116% Longitude:-79.3159°
lII� Elevation: 390.38 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_lahular I PF graph[ I M�ps_8 aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
oration Average recurrence interval (years)
F i6a I 2�0� 5�0�
5-min
0 39a 37
4B2
(0.470-0 568
0.547-0 663)
{0.804-0 732)
1*0
7 0.6770 815
(0.72 -8 B74)
1(0,76 -0 931)
(0} f!03-0 986)
j(6.850-1005)
(t1.886-1.11)
10-min
(0.638-0.769)
{0.752-0 9161
: 7{07--61306)
(0.967-16.17
(1.07-11830)
(1.15-21 39)
(1.21-3154s)
[1: 74358]
(1.34-1.67)
(1.40--1974
0.872
1.04
1.22
1.35
1.50
1.61
1.71
1.80
1.91
1.99
15-min
{0.7854:962
(0.945-1.14
(1,11-1.34)
(1.22-1,48
(1..3&1,65)
(1.45-1.76)
(1.53-1.87)
(1.61-1.9
1.69-2.10)
( 1,75-2.1.8
1.20
1.43
1.73
1.95
2.22
2.42
2.62
2.80
3.04
3.22
30-min
(1.09-1.32
1.31-1.58)
(1.58-1.91)
(1.77-2.15)
2.01-2.44)
(2,19-2.66)
2.35.2.87}
(2.50-3,07)
( 2.69-3.34)
84-354
1.49
1.80
2.22
2.54
2.96
3.28
3.60
3.93
F 4.37
4.71
60-min
1.36-1.64
(1.64-1.98)
(2.92-2.45)
(2,31-2.79)
2,67-3,25
(2.96-3.60)
(3.23-3.95
3.51-4,30] J1
(3.8e-4,79)
4.14-5.17
2-hr
2.66
1.5B74s4
(1.91-12.35)
(2.40-2.95)
(1760.41.)
1 (3: 5.4.02)
{3.63�4.57
4.005,00
(4,37 6.60)
1(4.87-6.18
(5: 5-5,72)
3-hr
1.84
2.23
1 2.82
1 3.28
1 3.92
4.45
4.99
5.56
6.36
7.00
(1.67-2.06)
(2.02-2.50)
12.55-3.14
(2.86-3.66
3.51-4.38)
(3.96-4.94)
1 (4.41=5.53}
4.87-B.16)
5.51-7.05)
6.00-7.76)
6-hr
(1, 9 244)
(2.42 2.95)
(3.05-3.72)
1 ((1544.34).
4. 2-5 19)
(4. 635.89
{5.32 8162)
(5. a 7?38)
1(6: 8-8.48
7. 059.36)
2.59
3.14
3.98
4.67
5.64
6.45
7.30
8.22
9.53
10.6
12-hr
(2.34-2.SB)
1 (2,04-3.49)
(3.60-4.42)
1 (4,20-5:18.
5.04-04]
5,71-7.11
6.41-8.04)
(7.14-9.04)
l(B.15-10.5)
(8.96-11,7)
3.05
3.69
4.67
5.46
6.52
7.37
8.25
9.17
10.4
11.4
24-hr
(283 3.30)
3.42-4.00)
4.32-5.06
5,02-5,89
(5;04-7.04)
(B.76-7.9B)
(7.54•B.B2}
j (8.36-8.90)
9.46-11.3)
(10.3-12A)
3.54
4.28
5.37F
6.24
7.43
8.38
9.36
10.4
11.8
12.9
2-day
(3,30-3,82
3.98-4.81)
{4.99-5.79)
5,78-6.71)
(&86-7.99)
(7.71-9.01)
(8.59-10.1)
(9,48-11.
( 10.7-12.7)
{ 11.7-13,9]
3.76
4.53
5.66
6.55
7.77
8.75
9.76
10.8
12.2
13.4
3-day
3.5.14.03
C23-4.68)
1 (5,27-6.06)
1 {6.09-7.01]
(7.20.8.32)
1 (8.09-9.37)
(8.99-10.5)
(11.2-13.1)
12.2-14.4
3.98
3.9
4-day
3.73 4 25)
[4.4&5.11 ]
{5.559fi 34}
6:90 7631.
(7.55 8 66
(B.4Yr9 73
9.38 fl:8
(10 3 2.0
{118�13.8]
1216-14.8
4.61
5.51
6.76
7.75
9.11
10.2
11.3
12.5
14.0
15.3
7-day
(4.31.4.93)
(5.16:5.89
6.32-7.23
7.235.29
9:48-0.74 ]
[ 9.dB-18.9 ]
10.5-12.1
71.5-13.3
12.9-15.0
14.0-1$.4
5.29
6.30
7.61
8.64
10.0
11.1
12.2
13.3
14.8
16.0
10-day
(4.98-5.62)
5.93-6,710
i,1&8.0$)
(a,11-9.17)
(9.39-10.6)
(10.4-11.B)
(11.4-13.0)
(12,4 14.2)
(13.7-15.8)
(14.8-17.1)
2
12.9
1
96 9
1
0.1
20-day
?
(6.72-(
7.53
(7.95 8.91)
(9.43-100.6)
(10.6-11.9)
(12 - 3.7.
13.3--15.1
(14•b- S.5
169
(17.819.9)
186-214
i2.2
i
30-day
5 4
7---17.6
8: 5-9.34}
9.8 .0)
(11.5-12.9)
(12.4 8-.3
14 4 6.2}
15
16.9--19.1
18.2-20.5
(19.8122.5)
(21?0-24.0)
11.2
13.1
F 16.1
16.6
18.5
20.0
21.4
22.8
24.7
26.1
45-day
(10.6-11.8) .
(12.4-13.8)
1 (14.3-15.9)
15.7-17.5)
{17.5-19.5]
18.8-21.1)
(20.2-22.6)
(21.5-24.1)
23.1-26.1)
(24.4-27.7)
3.4
6.7
7.8
5
19"
4.7
28.2
9.7
60-day
9-
127- 4.1
14 65]
16.19 8:7]
(18.5-20.5}
(20.4-2.7
21 8-24.4
23?4 28.0
242627,7)
(26.5-29,8]
27Z8- 1.4
1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for
a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are
not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PIMP values.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical
https://hdsc.nws.noaa.gov/hdscfpfds/pfds_printpage.html?lat=35.0116&Ion=-79.3159&data=depth&units=english&series=pds 1 /4

WATER QUANTITY

INFILTRATION TRENCH #1

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #1
Drainage Area (acres): 4.89
Existing Soil Groups:
Soil Grout/ Man Symbol Soil Description Acres Percent of DA
A AuA Autryville Loamy Sand 0.49 10%
A CaB Candor Sand 4.40 90%
A/D Ra Rains Sandy Loam 0.00 0%
Existing Land Uses. -
Land Use Description Existing Soil Group Acres Curve # Weighted CN
Open Space - Good Stand A 4.89 55 55.0
Cumulative Curve # = 55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #1
Drainage Area (acres 4.89
Existing Soil Grou s:
Soil Grow Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.49
10%
A CaB Candor Sand
4.40
90%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses:
Land Use Description Existina Soil Group Acres
Curve #
Weighted CN
Impervious Area -Residential Lots A 1.93
98
38.7
Impervious Area-Sidewalk/Road A 0.68
98
13.6
Open Space - Good Condition A 2.28
55
25.6
Cumulative Curve # =
78.0

Infiltration Trench ❑esian
Site Information
Sub Area Location:
Drainage To Infiltration Trench 1
Drainage Area (DA) =
489 Acres 212925 sf
Impervious Area (IA) =
2.61 Acres 113469 sf
Percent Impervious (1) =
53.3 %
Required Water Quality Volume
Design Storm = inch
Determine Rv Value = 0.05 + .009 (1) = 0.53 in/in
Water Quality Volume = 0.216 ac-ft
Water Quality Volume = 9,397 cf
Water Quality Volume = 0.530 inches of runoff
NOAA 1-year, 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA= (12"FS-DV)/(K-T)
Factor of Safety (FS) =
2
Design Volume (DV) =
9397.4 cf
Hydraulic Conductivity of Soil =
39.00 in/hr
Max Dewatering Time =
72 hours
SA Required =
80.3 sf
SA Provided =
965 sf

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'STAGE/STORAGE TABLE
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL
(FT) (FT) AREA (SF) STORAGE (CF) STORAGE (CF)
0.0
380.0
965
0
0
1.0
381.0
2005
1485
1485
2.0
382.0
3105
2555
4040
3.0
383.0
4275
3690
7730
4.0
384.0
5505
4890
12620 (WQv)
5.0
385.0
6805
6155
18775
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH #1
RIVER BASIN: CAPE FEAR
RECEIVING STREAM: MILL CREEK
STREAK INDEX: 18-31-11
STREAM CLASS: C
HUC: 03030004
DRAINAGE AREA TO SCM: 4.89 ACRES
SITE IMPERVIOUS AREA TO SCM: 2.61 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 2.61 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 4.89 AC 4.89 AC
CURVE NUMBER: 55 78
TIME OF CONCENTRATION: 34 MIN 5 MIN
1-YEAR STORM EVENT:
0.275 CFS
9.685 CFS
0.000 CFS
2-YEAR STORM EVENT:
0.854 CFS
13.60 CFS
0.000 CFS
10-YEAR STORM EVENT:
3.840 CFS
25.37 CFS
0.000 CFS

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i
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Pond Report s
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Wednesday, Jan 13, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas Average end area method used for volume calculation.
Begining Elevation = 380.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sqft)
Incr. Storage (cuft)
Total storage (cuft)
0.00 380.00
965
0
0
1.00 381.00
2,005
1,485
1,485
2.00 382.00
3,105
2,555
4,040
3.00 383.00
4,275
3,690
7,730
4.00 384.00
5,505
4,890
12,620
5.00 385.00
6.805
6.155
18.775
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A]
[B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 0.00
0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00
0.00
0.00
000
No. Barrels
= 0
0
1
0
Weir Coeff.
= 2.60
3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad
---
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage
= No
No
No
No
Slope (%)
= 0.00
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)
= 39.000 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
5.00
4.00
3.00
2.00
1.00
0.00
0.00 1.00
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)
Stage / Discharge
200 3.00 4.00 5.00 6.00
Elev (ft)
385.00
384.00
383.00
382.00
381.00
380.00
7.00
Discharge (cfs)

H yd rog ra p h Summary Re PyPraf ow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Total
Hydrograph
strge used
description
(cult)
------
BMP Pre -Developed
------
BMP Post -Developed
5,132
Post Through Pond
Wednesday, Jan 13, 2021

%A
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
BMP Pre -Developed
Wednesday, Jan 13, 2021
Peak discharge = 0.275 cfs
Time to peak
= 752 min
Hyd. volume
= 3,645 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 34.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 -.. - - — 0.50
0.45 -- - --- 0.45
0.40 0.40
0.35 0.35
0.30 0.30
0.25 - 0.25
0.20 0.20
0.15 0.15
0.10 - 0.10
0.05 1 - - - - 0.05
0.00- — - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 1

3
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tic method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
F.M1111
It,
4.00
2.00
0.00
0 120 240
Hyd No. 2
BMP Post -Developed
Hyd. No. 2 -- 1 Year
360 480 600 720 840
Wednesday, Jan 13, 2021
Peak discharge = 9.685 cfs
Time to peak =
718 min
Hyd. volume =
19,380 cuft
Curve number
= 78
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
10.00
f
MIX
4.00
we
0.00
960 1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D0 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
M$
N. W
4.00
It
we
Post Through Pond
Hyd. No. 3 -- 1 Year
120 240 360 480 600 720
Hyd No. 3 Hyd No. 2
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
4
Wednesday, Jan 13, 2021
= 0.000 cfs
= 796 min
= 0 cult
= 382.30 ft
= 5,132 cuft
Q (cfs)
10.00
Me
4.00
2.00
0.00
840 960 1080 1200 1320 1440
Total storage used = 5,132 cult Time (min)

Hyd rog ra p h Summary Re py3rall w Hydrographs Extension for AutoCADO Civil 3D® 2009 by Autodesk, Inc. v6.066

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3138 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
BMP Pre -Developed
7
Wednesday, Jan 13, 2021
Peak discharge = 0.854 cfs
Time to peak
= 740 min
Hyd. volume
= 7,226 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 34.00 min
Distribution
Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 2 Year
1.00 - -� 1.00
0.90 - 0.90
0.80 0.80
0.70 0.70
0.60 - 0.60
0.50 0.50
0.40 - - 0.40
0.30 0.30
0.20 0-20
0.10 — - 0.10
0.00 L 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

8
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
Q (cfs)
14.00
12.00
10.00
IR
4.00
2.00
BMP Post -Developed
Hyd. No. 2 -- 2 Year
Wednesday, Jan 13, 2021
Peak discharge = 13.60 cfs
Time to peak
= 718 min
Hyd. volume
= 27,345 cuft
Curve number
= 78
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
14.00
12.00
10.00
MM
M
4.00
2.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 2 Time (min)

9
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type =
Reservoir
Storm frequency =
2 yrs
Time interval =
2 min
Inflow hyd. No. =
2 - BMP Post -Developed
Reservoir name =
BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
14.00
12.00
10.00
M
M
4.00
2.00
0.00
0 120 240
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 2 Year
360 480 600
Hyd No. 2
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 746 min
Hyd. volume
= 0 cult
Max. Elevation
= 383.04 ft
Max. Storage
= 7,922 cuft
Q (cfs)
14.00
12.00
10.00
M
M
4.00
2.00
0.00
720 840 960 1080 1200
Total storage used = 7,922 cult Time (min)

10
Hydrograph Summary Re Ry3ra ow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd.
No.
1
Hydrograph
type
(origin)
SCS Runoff
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
-
Total Hydrograph
strge used description
(cuft)
-- BMP Pre -Developed
3.840
2
738
21,276
-
2
SCS Runoff
25.37
2
716
51,549
— -
- BMP Post -Developed
3
Reservoir
Trench#1.gpw
0.000
2
688
0
Return Period:
2
10
384.72
16,961 Post Through Pond
Wednesday, Jan 13, 2021
Infiltration
Year

11
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tc method
USER
Total precip. T
5.45 in
Storm duration =
24 hrs
KM
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
120 240 360 480 600 720 840
Hyd No. 1
Wednesday, Jan 13, 2021
Peak discharge = 3.840 cfs
Time to peak =
738 min
Hyd. volume =
21,276 cuft
Curve number =
55
Hydraulic length =
0 ft
Time of conc. (Tc)
= 34.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
4.00
3.00
2.00
MIX
0.00
960 1080 1200 1320 1440 1560
Time (min)

12
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.890 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
Q (cfs)
28.00
24.00
20.00
16.00
12.00
Me
4.00
BMP Post -Developed
Hyd. No. 2 -- 10 Year
Wednesday, Jan 13, 2021
Peak discharge = 25.37 cfs
Time to peak
= 716 min
Hyd. volume
= 51,549 cuft
Curve number
= 78
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
Type II
Shape factor
= 484
Q (cfs)
28.00
24.00
20.00
16.00
12.00
[.*&W
4.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440
Time (min)
Hyd No. 2

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD@ Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
28.00
24.00
20.00
16.00
12.00
: 1I
4.00
Post Through Pond
Hyd. No. 3 -- 10 Year
13
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 688 min
Hyd. volume
= 0 cuft
Max. Elevation
= 384.72 ft
Max. Storage
= 16,961 cuft
Q (cfs)
28.00
24.00
20.00
16.00
12.00
M.
4.00
0.00 -1 j- - .L .-. 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Hyd No. 2 Total storage used = 16,961 cult Time (min)

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INFILTRATION TRENCH #2

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #2
Drainage Area (acres: 1.84
Existing Soil Groups:
soil Grouo Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
1.84
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses_:
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Open Space - Good Stand A 1.84
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #2
Drainage Area (acres 1.84
Existing Soil Groups:
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
1.84
100%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses.
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Impervious Area -Residential Lots A 0.83
98
44.2
Impervious Area-Sidewalk/Road A 0.29
98
15.4
Open Space - Good Condition A 0.72
55
21.5
Cumulative Curve # =
81.2

Infiltration Trench Des
Site Information
Sub Area Location:
Drainage To Infiltration Trench 2
Drainage Area (DA) =
1.84 Acres 80165 sf
Impervious Area (IA) =
1.12 Acres 48933 sf
Percent Impervious (1) =
61.0 %
Required Water Quality Volume
Design Storm =
i inch
Determine Rv Value =
0.05 + .009 (1) = 0.60 in/in
Water Quality Volume =
0.092 ac-ft
Water Quality Volume =
4,004 cf
Water Duality Volume =
0.599 inches of runoff
NOAA 1- ear, 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12'FS'DV)/(K'T)
Factor of Safety (FS) =
2
Design Volume (DV) =
4004.0 cf
Hydraulic Conductivity of Soil =
2.17 in/hr
Max Dewatering Time =
72 hours
SA Required =
615.1 sf
SA Provided =
840 sf

STAGE
STORAGE
TABLE
STAGE
ELEVATION
CONTOUR
INCREMENTAL
TOTAL
(FT)
(FT)
AREA (SF)
STORAGE (CF)
STORAGE (CF)
0.0
381.0
840
0
0
1.0
382.0
2150
1495
1495
2.0
383.0
3565
2858
4353 (WQv)
3.0
384.0
5040
4303
8655
4.0
385.0
6590
5815
14470
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH #2
RIVER BASIN: CAPE FEAR
RECEIVING STREAK: MILL CREEK
STREAM INDEX: 18-31-11
STREAM CLASS: C
HUC: 03030004
DRAINAGE AREA TO SCM: 1.84 ACRES
SITE IMPERVIOUS AREA TO SCM: 1.12 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 1.12 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 1.84 AC 1.84 AC
CURVE NUMBER: 55 81.2
TIME OF CONCENTRATION: 36 MIN 5 MIN
1-YEAR STORM EVENT:
0.103 CFS
4.249 CFS
0.000 CFS
2-YEAR STORM EVENT:
0.321 CFS
5.822 CFS
0.000 CFS
10-YEAR STORM EVENT:
1.445 CFS
10.40 CFS
0.000 CFS

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Pond Report 5
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D@ 2009 byAutodesk, Inc. v6.066 Wednesday, Jan 13, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas. Average end area method used for volume calculation. Begining Elevation = 381.00 ft
Stage / Storage Table
Stage (ft)
Elevation (ft)
Contour area (sgft)
Incr. Storage (cuft)
Total storage (cuft)
0.00
381.00
840
0
0
1.00
382.00
2,150
1.495
1,495
2.00
38300
3,565
2.858
4,353
3.00
384.00
5,040
4.303
8,655
4.00
385.00
6,590
5.815
14,470
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A] [B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 000 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00 0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff.
= 2.60 3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad ---
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage
= No No
No
No
Slope (%)
= 0.00
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeft.
= 0.60
0.60
0.60
0.60
Exfil.(in/hr)
= 2.170 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
4.00
3.00
2.00
1.00
0.00
0.00 0.04
Total Q
Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (cc) control Weir risers checked for orifice conditions (ic) and submergence (s)
Stage / Discharge
0.08 0.12 0.16 0.20 0.24 0.28 0.32 0.36
Elev (ft)
385.00
384.00
383.00
382.00
381.00
0.40
Discharge (cfs)

Hyd rog ra p h Summary Re I?y3rftflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
0.103
Time
interval
(min)
2
Time to
peak
(min)
752
1
SCS Runoff
2
SCS Runoff
4.249
2
718
3
Reservoir
0.000
2
768
Infiltration Trench#2.gpw

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 1.840 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
BMP Pre -Developed
2
Wednesday, Jan 13, 2021
Peak discharge = 0.103 cfs
Time to peak
= 752 min
Hyd. volume
= 1,372 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 36.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 0.50
0.45 - 0.45
0.40 0.40
0.35 0.35
0.30 - — 0.30
0.25 0.25
0.20 0.20
0.15 -F - 0.15
0.10 - 0.10
0.05 - 0.05
0.00 A..— - - ., _ _ _ �I 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

3
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3130 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
1.840 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
Q (cfs)
5.00
4.00
CM
2.00
1.00
BMP Post -Developed
Hyd. No. 2 -- 1 Year
Wednesday, Jan 13, 2021
Peak discharge = 4.249 cfs
Time to peak
= 718 min
Hyd. volume
= 8,548 cuft
Curve number
= 81.2
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
5.00
4.00
3.00
2.00
1.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 2 Time (min)

4
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD@ Civil 31302009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
5.00
4.00
3.00
2.00
1.00
0.00
0 240
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 1 Year
480 720 960
Hyd No. 2
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Wednesday, Jan 13, 2021
= 0.000 cfs
= 768 min
= 0 cuft
= 383.04 ft
= 4,530 cult
1200 1440 1680 1920 2160
Total storage used = 4,530 cuft
Q (cfs)
5.00
4.00
3.00
2.00
1.00
0.00
2400
Time (min)

Hydrograph Summary Re py3raflow Hydrographs Extension for AutoCAD® Civil 3130 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
--•-
Maximum
elevation
(ft)
------
Total
strge used
(cuft)
------
Hydrograph
description
BMP Pre -Developed
1
SCS Runoff
0.321
2
740
2,719
2
SCS Runoff
5.822
2
716
11,765
------
------
---
BMP Post -Developed
3
Reservoir
0.000
2
722
0
2
383.52
6,592
Wednesday,
Post Through Pond
Jan 13, 2021
Infiltration
Trench#2.gpw
Return Period:
2 Year

N
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 1.840 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
BMP Pre -Developed
Wednesday, Jan 13, 2021
Peak discharge = 0.321 cfs
Time to peak
= 740 min
Hyd. volume
= 2,719 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 36.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Hyd. No. 1 -- 2 Year Q (cfs)
0.50 0.50
0.45 - 0.45
0.40 0.40
0.35 0.35
0.30 0.30
0.25 0.25
0.20 0.20
0.15 0.15
0.10 - - 0.10
0.05 �- 0.05
l_
0.00 _ _.. = 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

8
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 31302009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 1.840 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
Q (cfs)
6.00
5.00
4.00
MIX
2.00
1.00
BMP Post -Developed
Hyd. No. 2 -- 2 Year
Wednesday, Jan 13, 2021
Peak discharge = 5.822 cfs
Time to peak
= 716 min
Hyd. volume
= 11,765 cuft
Curve number
= 81.2
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
6.00
5.00
M
3.00
2.00
1.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 2 Time (min)

9
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
5.00
4.00
3.00
2.00
1.00
Post Through Pond
Hyd. No. 3 -- 2 Year
240 480 720 960
Hyd No. 3 Hyd No. 2
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Wednesday, Jan 13, 2021
= 0.000 cfs
= 722 min
= 0 cuft
= 383.52 ft
= 6,592 cult
Q (cfs)
6.00
m
4.00
3.00
2.00
1.00
0.00
1200 1440 1680 1920 2160 2400 2640
Total storage used = 6,592 cult Time (min)

10
Hydrograph Summary Re I?gra'3w Hydrographs Extension forAutoCAD® Civil 31382009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
SCS Runoff
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
- -
Maximum
elevation
(ft)
--
Total
strge used
(cuft)
Hydrograph
description
1
1.445
2
738
8,006
------
BMP Pre -Developed
2
SCS Runoff
10.40
2
716
21,326
-
-----
-- -
BMP Post -Developed
3
Reservoir
0.000
2
714
0
Return Period:
2
i
10
384.73
Year
12,909
Post Through Pond
Infiltration
Trench#2.gpw
Wednesday,
Jan 13, 2021

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D®2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 1.840 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.45 in
Storm duration
= 24 hrs
BMP Pre -Developed
Q (cfs) Hyd. No. 1 -- 10 Year
2.00
1.00
M
120 240 360 480 600 720 840 960
Hyd No. 1
11
Wednesday, Jan 13, 2021
Peak discharge = 1.445 cfs
Time to peak
= 738 min
Hyd. volume
= 8,006 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 36.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
2.00
1.00
0.00
1080 1200 1320 1440 1560
Time (min)

12
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 3D0 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 1.840 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.45 in
Storm duration
= 24 hrs
Q (cfs)
12.00
10.00
F.M1111
. M
4.00
2.00
BMP Post -Developed
Hyd. No. 2 -- 10 Year
Wednesday, Jan 13, 2021
Peak discharge = 10.40 cfs
Time to peak
= 716 min
Hyd. volume
= 21,326 cuft
Curve number
= 81.2
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
12.00
10.00
e
we]
4.00
2.00
0.00 -I ' - J 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
Hyd No. 2 Time (min)

Hlydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
10.00
: W
WE
4.00
2.00
W,
Post Through Pond
Hyd. No. 3 -- 10 Year
240 480 720 960
Hyd No. 3 Hyd No. 2
13
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 714 min
Hyd. volume
= 0 cuft
Max. Elevation
= 384.73 ft
Max. Storage
= 12,909 cuft
Q (cfs)
12.00
10.00
UQ
. ff
4.00
2.00
0.00
1200 1440 1680 1920 2160 2400 2640
Total storage used = 12.909 tuft Time (min)

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NFILTRATION TRENCH #3

^'�SCvCL

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #3
Drainage Area (acresj: 2.56
Existing Soil Groups:
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.56
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses:
Land Use Description Existinq Soil Group Acres
Curve #
We _eihted CN
Open Space - Good Stand A 2.56
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #3
Drainaoe Area (acres Z 2.56
Existing Soil Groups:
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.56
100%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
Weighhled CN
Impervious Area -Residential Lots A 1.65
98
63.2
Impervious Area-Sidewalk/Road A 0.23
98
8.8
Open Space - Good Condition A 0.68
55
14.6
Cumulative Curve # =
86.6

Infiltration Trench Design
Site Information
Sub Area Location:
Drainage To Infiltration Trench 3
Drainage Area (DA) =
2.56 Acres 111705 sf
Impervious Area (IA) =
1.88 Acres 81750 sf
Percent Impervious (1) =
73.2 %
Required Water Quality Volume
Design Storm = inch
Determine Rv Value = 0.05 + .009 (1) = 0.71 in/in
Water Quality Volume = 0.151 ac-ft
Water Quality Volume = 6,597 cf
Water Quality Volume = 0.709 inches of runoff
NOAA 1-yea r, 24-hour event = 305 inches
Minimum Surface Area (SA)
SA = (12'FS'DV)/(K'T)
Factor of Safety (FS) =
2
Design Volume (DV) =
6596.7 cf
Hydraulic Conductivity of Soil =
2.17 in/hr
Max Dewatering Time =
72 hours
SA Required =
1013.3 sf
SA Provided =
1870 sf

'STAGE/STORAGE
TABLE
STAGE
ELEVATION
CONTOUR
INCREMENTAL
TOTAL
(FT)
(FT)
AREA (SF)
STORAGE (CF)
STORAGE (Cr)
0.0
384.0
1870
0
0
1.0
385.0
3910
2890
2890
2.0
386.0
6100
5005
7895 (WQv)
3.0
387.0
8460
7280
15175
4.0
388.0
10980
9720
24895
STORMWATER MANAGEMENT
INFILTRATION TRENCH #3
RIVER BASIN: CAPE FEAR
RECEIVING STREAM: MILL CREEK
STREAM INDEX: 18-31-11
STREAM CLASS: C
HUC: 03030004
SCE! D
DESIGN
DRAINAGE AREA TO SCM: 2.56 ACRES
SITE IMPERVIOUS AREA TO SCM: 1.88 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 1.88 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 2.56 AC 2.56 AC
CURVE NUMBER: 55 86.6
TIME OF CONCENTRATION: 19 MIN 5 MIN
1-YEAR STORM
EVENT:
0.189 CFS
7.505 CFS
0.000 CFS
2-YEAR STORM
EVENT:
0.680 CFS
9.846 CFS
0.000 CFS
10-YEAR STORM
EVENT:
3.093 CFS
16.35 CFS
0.000 CFS

Pond Report 5
Hydraflow Hydrographs Extension forAutoCADO Civil 313102009 byAutodesk, Inc. v6.066
Thursday, Jan 14, 2021
Pond No. 1
- BMP Pond
Pond Data
Contours - User -defined contour areas.
Average end
area method used for volume calculation. Begining Elevation
= 384.00
ft
Stage / Storage Table
Stage (ft)
Elevation (ft)
Contour area (sqft)
Incr. Storage (cuft) Total storage (cuft)
0.00
384.00
1,870
0 0
1.00
385.00
3,910
2,890 2,890
200
386.00
6,100
5,005 7,895
3.00
387.00
8,460
7,280 15,175
4.00
388.00
10,980
9,720 24,895
Culvert I Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A] [B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft) = 0.00 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft) = 0.00 0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff. = 2.60 333
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type = Broad ---
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage = No No
No
No
Slope (%)
= 0.00
0.00
0.00
n/a
N-Value
= 013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
0.60
060
Exfil.(in/hr) = 2.170 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft) = 0.00
Stage (ft)
4.00
3.00
2.00
1.00
0.00 ' '
0.00 0.06
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)
Stage / Discharge
0.12 0.18 0.24 030 0.36 0.42 0.48 0.54
Elev (ft)
388.00
387.00
386.00
385.00
---L- 384.00
0.60
Discharge (cfs)

Hydrograph Summary Re RQra-flow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
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
0.189
2
732
1,930
- --
--
BMP Pre -Developed
2
SCS Runoff
7.505
2
716
15,260
- ___
______
____
BMP Post -Developed
i
3
Reservoir
0.000
2
1572
0
2
386.08
8,507
Thursday,
Post Through Pond
Jan 14, 2021
Infiltration
Trench#3.gpw
Return Period:
1 Year

r%.
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADG Civil 3D® 2009 byAutodesk, Inc, v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 2.560 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
BMP Pre -Developed
Thursday, Jan 14, 2021
Peak discharge = 0.189 cfs
Time to peak =
732 min
Hyd. volume =
1,930 cuft
Curve number =
55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 19.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 0.50
0.45 0.45
0.40 0.40
0.35 0.35
0.30 0.30
0.25 0.25
0.20 0.20
0.15 - - - 0.15
0.10 1 - 0.10
0.05 - - 0.05
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
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D@ 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 2.560 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
More
4.00
2.00
3
Thursday, Jan 14, 2021
Peak discharge = 7.505 cfs
Time to peak
= 716 min
Hyd. volume
= 15,260 cuft
Curve number
= 86.6
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
BMP Post -Developed
Hyd. No. 2 -- 1 Year
120 240 360 480 600 720 840 960
Hyd No. 2
Q (cfs)
8.00
M
4.00
2.00
0.00
1080 1200 1320 1440
Time (min)

Hydrograph Report
4
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Post Through Pond
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Thursday, Jan 14. 2021
= 0.000 cfs
= 1572 min
= 0 cult
= 386.08 ft
= 8,507 cult
Q (cfs) Hyd. No. 3 -- 1 Year Q (cfs)
8.00 8.00
6.00 6.00
4.00 4.00
2.00 2.00
0.00 — - 0.00
0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880
Time (min)
— Hyd No. 3 Hyd No. 2 Total storage used = 8,507 cult

H yd rog ra p h Summary Re Plyarar ow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 2.560 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
BMP Pre -Developed
7
Thursday, Jan 14, 2021
Peak discharge = 0.680 cfs
Time to peak
= 728 min
Hyd. volume
= 3,826 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 19.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 2 Year
1.00 - 1.00
0.90 - - 0.90
0.80 0.80
0.70 0.70
0.60 0.60
0.50 0.50
0.40 0.40
0.30 0.30
0.20 0.20
0.10 0.10
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
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D@ 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 2.560 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
. 11
4.00
2.00
I II
we
BMP Post -Developed
Hyd. No. 2 -- 2 Year
8
Thursday, Jan 14, 2021
Peak discharge = 9.846 cfs
Time to peak
= 716 min
Hyd. volume
= 20,204 cuft
Curve number
86.6
Hydraulic length
= 0 ft
Time of conc. (Tc)
5.00 min
Distribution
= Type II
Shape factor
= 484
120 240 360 480 600 720 840 960
Hyd No. 2
Q (cfs)
10.00
M
ME
4.00
2.00
0.00
1080 1200 1320
Time (min)

Hydrograph Report
9
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
M
. el
4.00
2.00
0.00
0 240 480
— Hyd No. 3
720
Post Through Pond
Hyd. No. 3 -- 2 Year
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Thursday, Jan 14, 2021
= 0.000 cfs
= 690 min
= 0 cult
= 386.52 ft
= 11,699 cult
Q (cfs)
10.00
as,
we]
4.00
2.00
0.00
960 1200 1440 1680 1920 2160 2400 2640 2880
Hyd No. 2 Total storage used = 11,699 cult Time (min)

10
Hyd rog ra p h Summary Re pQra-flew Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
al Hydrograph
used description
ift)
BMP Pre -Developed
BMP Post -Developed
Post Through Pond
sday, Jan 14, 2021

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 2.560 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.45 in
Storm duration
= 24 hrs
Q (cfs)
4.00
3.00
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
11
Thursday, Jan 14, 2021
Peak discharge = 3.093 cfs
Time to peak
= 726 min
Hyd. volume
= 11,266 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 19.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
4.00
3.00
r M
1.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

Hydrograph Report
12
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
2.560 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
Q (cfs
18.00
15.00
12.00
8M
c It O
BMP Post -Developed
Hyd. No. 2 -- 10 Year
Thursday, Jan 14, 2021
Peak discharge = 16.35 cfs
Time to peak =
716 min
Hyd. volume =
34,423 cuft
Curve number =
86.6
Hydraulic length =
0 ft
Time of conc. (Tc) =
5.00 min
Distribution =
Type II
Shape factor
= 484
Q (cfs)
18.00
15.00
12.00
• M0
MI
3.00
0.00 - `"" 0.00
0 120 240 360 480 600 720 840 960 1080 1200
— Hyd No. 2 Time (min)

Hydrograph Report
13
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
15.00
12.00
M
WE
3.00
M
240 480
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 10 Year
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Thursday, Jan 14, 2021
= 0.000 cfs
= 932 min
= 0 cuft
= 387.61 ft
= 21,056 cuft
Q (cfs)
18.00
15.00
12.00
3.00
0.00
720 960 1200 1440 1680 1920 2160 2400 2640 2880
Hyd No. 2 Total storage used = 21,056 cult Time (min)

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NFILTRATION TRENCH #4

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #4
Drainage Area (acres 4.25
Existing Soil Groin:
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
4.25
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existng Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
W_ eighted CN
Open Space - Good Stand A 4.25
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #4
Oraina, a Area LacrasZ 4.25
Exisdw Soil Groups:
Soil Grouo Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
4.25
100%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses'
Land Use Description Existing Soil Group Acres
Curve #
Wei_ahted CN
Impervious Area -Residential Lots A 2.20
98
50.7
Impervious Area-Sidewalk/Road A 0.49
98
11.3
Open Space - Good Condition A 1.56
55
20.2
Cumulative Curve # =
82.2

Infiltration Trench Design
Site Information
Sub Area Location:
Drainage To Infiltration Trench 4
Drainage Area (DA) =
4.25 Acres 185040 sf
Impervious Area (IA) =
2.69 Acres 117141 sf
Percent Impervious (1) =
63.3 %
Required Water Quality Volume
Design Storm = 1 inch
Determine Rv Value = 0.05 + .009 (1) = 0.62 in/in
Water Quality Volume = 0.219 ac-ft
Water Quality Volume = 9,557 cf
Water Quality Volume = 0.620 inches of runoff
NOAA 1 ear, 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12-FS"DV)/(K-T)
Factor of Safety (FS) =
2
Design Volume (DV) =
9556.6 cf
Hydraulic Conductivity of Soil =
43.00 in/hr
Max Dewatering Time =
72 hours
SA Required =
74.1 sf
SA Provided =
1 sf

('S'-TAGE/STORAGE
TABLE
STAGE
ELEVATION
CONTOUR
INCREMENTAL
TOTAL
(FT)
(FT)
AREA (SF)
STORAGE (CF)
STORAGE (CF)
0.0
384.0
1170
0
0
1.0
385.0
2480
1825
1825
2.0
386.0
3930
3205
5030
3.0
387.0
5850
4890
9920 (WQv)
4.0
388.0
9010
7430
17350
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH #4
RIVER BASIN:
RECEIVING STREAM:
STREAM INDEX:
STREAM CLASS:
HUC:
CAPE FEAR
MILL CREEK
18-31-11
C
03030004
SCM DESIGN SUMMARY
DRAINAGE AREA TO SCM: 4.25 ACRES
SITE IMPERVIOUS AREA TO SCM: 2.69 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 2.69 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH
DRAINAGE AREA: 4.25 AC 4.25 AC
CURVE NUMBER: 55 82.2
TIME OF CONCENTRATION: 25 MIN 5 MIN
1-YEAR STORM EVENT:
0.272 CFS
10.26 CFS
0.000 CFS
2-YEAR STORM EVENT:
0.919 CFS
13.98 CFS
0.000 CFS
10-YEAR STORM EVENT:
4.197 CFS
24.62 CFS
0.000 CFS

k
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k

Pond Report
�1
Hydraflow Hydrographs Extension for AutoCAD0 Civil 3D® 2009 by Autodesk, Inc. v6 066 Wednesday, Jan 13, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas. Average end area method used for volume calculation. Begining Elevation = 384.00 ft
Stage / Storage Table
Stage (ft)
Elevation (ft)
Contour area (sqft)
Incr. Storage (cuft)
Total storage (cuft)
0.00
384.00
1,170
0
0
1.00
385.00
2,480
1,825
1,825
200
386.00
3,930
3,205
5,030
3.00
387.00
5,850
4,890
9,920
4.00
388.00
9,010
7,430
17.350
Culvert / Orifice
Structures
Weir Structures
[A]
IB]
[C]
[PrfRSr]
[A] IB]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 0.00 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00 0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff.
= 2.60 3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad ---
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage
= No No
No
No
Slope (%)
= 0.00
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)
= 43.000 (by Contour)
Multi -Stage
= n/a
No
Yes
No
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 (ft)
4.00
3.00
2.00
1.00
0.00
0.00 1.00
Total Q
Stage / Discharge
2.00 3.00 4.00 5.00 6.00 7.00 8.00
Elev (ft)
388.00
387.00
386.00
385.00
384.00
9.00
Discharge (cfs)

Hydrograph Summary Re PAyara" flaw Hydrographs Extension for AutoCADO Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
SCS Runoff
Peak
flow
(cfs)
0.272
Time
interval
(min)
2
Time to
peak
(min)
740
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
F description
BMP Pre -Developed
1
3,155
------
—
---
2
SCS Runoff
10.26
2
718
20,711
----
- - —
-
BMP Post -Developed
3
Reservoir
0.000
2
766
0
2
386.05
5,208
Post Through Pond
Infiltration Trench#4.gpw
f Return Period: 1 Year
Wednesday, Jan 13, 2021

K
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
4.250 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
BMP Pre -Developed
Wednesday, Jan 13, 2021
Peak discharge = 0.272 cfs
Time to peak =
740 min
Hyd. volume =
3,155 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 25.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 - — 0.50
0.45 0.45
0.40 - 0.40
0.35 0.35
0.30 0.30
0.25 - 0.25
0.20 - - - 0.20
0.15 0.15
0.10 0.10
0.05 0.05
0.00 i - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

3
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066 Wednesday, Jan 13, 2021
Hyd. No. 2
BMP Post -Developed
Hydrograph type
= SCS Runoff
Peak discharge
= 10.26 cfs
Storm frequency
= 1 yrs
Time to peak
= 718 min
Time interval
= 2 min
Hyd. volume
= 20,711 cuft
Drainage area
= 4.250 ac
Curve number
= 82.2
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= USER
Time of conc. (Tc)
= 5.00 min
Total precip.
= 3.05 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
Q (cfs)
12.00
10.00
MI
. WO
Me
2.00
BMP Post -Developed
Hyd. No. 2 -- 1 Year
Q (cfs)
12.00
10.00
UR
. 00
4.00
2.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 2 Time (min)

4
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D0 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
12.00
10.00
4.00
2.00
0.00 -L
0
Post Through Pond
Hyd. No. 3 -- 1 Year
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 766 min
Hyd. volume
= 0 cuft
Max. Elevation
= 386.05 ft
Max. Storage
= 5,208 cuft
Q (cfs)
12.00
10.00
m
m
4.00
2.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 3 Hyd No. 2 Total storage used = 5,208 cult

Hydrograph Summary Re Pgra'flaw Hydrographs Extension for AutoCAD® Civil 3130 2009 by Autodesk, Inc. v6.066
yd.
o.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
6,253
Inflow
hyd(s)
------
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
description
BMP Pre -Developed
I
SCS Runoff
0.919
2
732
-- —
---
SCS Runoff
13.98
2
716
28,294
------
------
------
BMP Post -Developed
3
Reservoir
0.000
2
704
0
2
386.55
7,656
Post Through Pond
nfiltration Trench#4.gpw Return Period: 2 Year
Wednesday, Jan 13, 2021

7
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31302009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.250 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
BMP Pre -Developed
Wednesday, Jan 13, 2021
Peak discharge = 0.919 cfs
Time to peak
= 732 min
Hyd. volume
= 6,253 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 25.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Hyd. No. 1 -- 2 Year Q (cfs)
1.00 1.00
0.90 - 0.90
0.80 0.80
0.70 0.70
0.60 - 0.60
0.50 0.50
0.40 0.40
0.30 - 0.30
0.20 -I - 0.20
0.10 0.10
0.00 Y — — 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)
-,

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.250 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
Q (cfs)
14.00
12.00
10.00
M
WE
4.00
BMP Post -Developed
Hyd. No. 2 -- 2 Year
120 240 360 480 600
Hyd No. 2
Wednesday, Jan 13, 2021
Peak discharge = 13.98 cfs
Time to peak
= 716 min
Hyd. volume
= 28,294 cuft
Curve number
= 82.2
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
14.00
12.00
10.00
of
BU
M
2.00
0.00
720 840 960 1080 1200 1320 1440
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADS Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type =
Reservoir
Storm frequency =
2 yrs
Time interval =
2 min
Inflow hyd. No. =
2 - BMP Post -Developed
Reservoir name =
BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
14.00
12.00
10.00
m
AM
4.00
2.00
Post Through Pond
Hyd. No. 3 -- 2 Year
N.
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 704 min
Hyd. volume
= 0 cuft
Max. Elevation
= 386.55 ft
Max. Storage
= 7,656 cuft
Q (cfs)
14.00
12.00
10.00
es
. ff
4.00
2.00
0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 0.00
Time (min)
— Hyd No. 3 Hyd No. 2 Total storage used = 7,656 cult

10
Hyd rog ra p h Summary Re RQra'3w Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066

11
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.250 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
Q (cfs)
5.00
4.00
3.00
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
Wednesday, Jan 13, 2021
Peak discharge = 4.197 cfs
Time to peak =
730 min
Hyd. volume
= 18,412 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 25.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
5.00
4.00
3.00
2.00
1.00
0.00 1 - J1 i ! 1 1 � - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

12
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.250 ac
Basin Slope =
0.0 %
Tic method =
USER
Total precip. =
5.45 in
Storm duration -
24 hrs
24.00
20.00
16.00
12.00
M
4.00
I I
w
BMP Post -Developed
Hyd. No. 2 -- 10 Year
Wednesday, Jan 13, 2021
Peak discharge = 24.62 cfs
Time to peak =
716 min
Hyd. volume =
50,684 cuft
Curve number =
82.2
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
28.00
24.00
20.00
16.00
12.00
M
4.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320
Hyd No. 2 Time (min)

13
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D(02009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
28.00
24.00
20.00
16.00
12.00
M
4.00
Post Through Pond
Hyd. No. 3 -- 10 Year
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Wednesday, Jan 13, 2021
= 0.000 cfs
= 740 min
= 0 cuft
= 387.70 ft
= 15,049 cult
Q (cfs)
28.00
24.00
20.00
16.00
12.00
Mulls]
alff
0.00 ' - '- - ! 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 3 Hyd No. 2 Total storage used = 15,049 cult Time (min)

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INFILTRATION TRENCH #5

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #5
Drainage Area (acres Z 2.20
Existing Soil Groups
Soil Grout/ Man Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.20
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Open Space - Good Strand A 2.20
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #5
Drainage Area (acres: 2.20
Existing Soil Groups:
Sod Group Map Symbol Soil Description
Acres
Percent of DA.
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.20
100%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
Wei_ghted CN
Impervious Area -Residential Lots A 1.66
98
73.9
Impervious Area-Sidewalk/Road A 0.22
98
9.8
Open Space - Good Condition A 0.32
55
8.0
Cumulative Curve # =
91.7

Infiltration Trench Design
Site Information
Sub Area Location:
Drainage To Infiltration Trench 5
Drainage Area (DA) =
2.20 Acres 96006 sf
Impervious Area (IA) =
1.88 Acres 81698 sf
Percent Impervious (1) =
85.1 %
Required Water Quality Volume
Design Storm =
Determine Rv Value =
Water Quality Volume =
Water Quality Volume =
Water Quality Volume =
1 inch
0.05 + .009 (1) = 0.82 in/in
0.150 ac-ft
6,527 cf
0.816 inches of runoff
NOAA 1-vear. 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12`FS•DV)/(K*T)
Factor of Safety (FS) =
2
Design Volume (DV) =
6527.4 cf
Hydraulic Conductivity of Soil =
5.50 in/hr
Max Dewatering Time =
72 hours
SA Required =
395.6 sf
SA Provided =
1115 sf

STAGE STO RAGE TABLE
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL
(FT) (FT) AREA (SF) STORAGE (CF) STORAGE (Cr)
0.0
384.0
1115
0
0
1.0
385.0
2330
1723
1723
2.0
386.0
3645
2988
4710
3.0
387.0
5000
4323
9033 (WQv)
4.0
388.0
6415
5708
14740
5.0
369.0
7885
7150
21890
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH #5
RIVER BASIN:
RECEIVING STREAM:
STREAM INDEX:
STREAM CLASS:
HUC:
LUMBER
BUFFALO CREEK
14-2.5
C
03040203
0igIT111 ItuI&i1Pl'I1:fI
DRAINAGE AREA TO SCM: 2.20 ACRES
SITE IMPERVIOUS AREA TO SCM: 1.88 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 1.88 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SO TO SCM THROUGH SCM
DRAINAGE AREA: 2.20 AC 2.20 AC
CURVE NUMBER: 55 91.7
TIME OF CONCENTRATION: 21 MIN 5 MIN
1-YEAR STORM EVENT:
0.151 CFS
7.779 CFS
0.000 CFS
2-YEAR STORM EVENT:
0.525 CFS
9.808 CFS
0.000 CFS
10-YEAR STORM EVENT:
2.404 CFS
15.34 CFS
0.000 CFS

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Pond Report s
Hydraflow Hydrographs Extension forAutoCAD@ Civil 3D® 2009 byAutodesk, Inc. v6.066 Wednesday, Jan 13, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas Average end area method used for volume calculation. Begining Elevation = 384.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sqft)
Incr. Storage (cuft)
Total storage (cuft)
0.00 384.00
1,115
0
0
1 00 385.00
2,330
1,723
1,723
2.00 386.00
3,645
2.988
4,710
3.00 387.00
5,000
4,323
9,033
4.00 388.00
6,415
5,708
14,740
5.00 389.00
7,885
7,150
21,890
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A]
[B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 0.00
0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00
0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff.
= 260
3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage
= No
No
No
No
Slope (%)
= 0.00
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)
= 5.500 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
5.00
4.00
3.00
2.00
1.00
0.00
0.00
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)
0.50
Stage / Discharge
1.00
1.50
Elev (ft)
389.00
388.00
387.00
386.00
385.00
384.00
2.00
Discharge (cfs)

Hydrograph Summary Re PQra-foow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd.
No.
1
Hydrograph
type
(origin)
SCS Runoff
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cult)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total Hydrograph
strge used description
(cuft)
...... BMP Pre -Developed
0.151
2
738
1,688
-
—
2
SCS Runoff
7.779
2
716
16,328
—
---
------ BMP Post -Developed
3
Reservoir
0.000
2
898
0
Return Period:
2
1 Year
386.75
7,961 Post Through Pond
Wednesday, Jan 13, 2021
Infiltration
Trench#5.gpw

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31302009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 2.200 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
BMP Pre -Developed
2
Wednesday, Jan 13, 2021
Peak discharge = 0.151 cfs
Time to peak
= 738 min
Hyd. volume
= 1,688 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 21.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 - 0.50
0.45 ` + 0.45
0.40 0.40
0.35 - 0.35
0.30 0.30
0.25 0.25
0.20 0.20
0.15 0.15
0.10 0.10
0.05 _ 0.05
.. i - ��. -: .�.
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
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 2.200 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
Q (cfs)
8.00 - -
I
i
3
Wednesday, Jan 13, 2021
Peak discharge = 7.779 cfs
Time to peak
= 716 min
Hyd. volume
= 16,328 cuft
Curve number
= 91.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
AM
4.00
2.00
0.00
0
120 240
Hyd No. 2
BMP Post -Developed
Hyd. No. 2 -- 1 Year
360 480 600 720 840 960
Q (cfs)
8.00
4.00
2.00
0.00
1080 1200 1320
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31302009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
M
4.00
2.00
Post Through Pond
Hyd. No. 3 -- 1 Year
120 240 360 480 600 720
Hyd No. 3 Hyd No. 2
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
4
Wednesday, Jan 13, 2021
= 0.000 cfs
= 898 min
= 0 tuft
= 386.75 ft
= 7,961 cuft
Q (cfs)
8.00
. We
4.00
2.00
0.00
840 960 1080 1200 1320 1440 1560 1680 1800
Time (min)
Total storage used = 7,961 cuft

Hydrograph Summary Re RFiy3rdow Hydrographs Extension forAutoCAD® Civil 3138 2009 by Autodesk, Inc. v6.066
Hyd.
No,
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
3,347
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
description
BMP Pre -Developed
1
SCS Runoff
0.525
2
730
-
--
2
SCS Runoff
9.808
2
716
20,884
--
------
......
BMP Post -Developed
3
Reservoir
0.000
2
1012
0
2
387.24
10,393
Wednesday,
Post Through Pond
Infiltration
Trench#5.gpw
Return Period:
2 Year
Jan 13, 2021

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 2.200 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
BMP Pre -Developed
7
Wednesday, Jan 13, 2021
Peak discharge = 0.525 cfs
Time to peak
= 730 min
Hyd. volume
= 3,347 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 21.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Hyd. No. 1 -- 2 Year Q (cfs)
1.00 - 1.00
0.90 0.90
0.80 0.80
0.70 0.70
0.60 0.60
0.50 0.50
0.40 - 0.40
0.30 - 0.30
0.20 0.20
0.10 0.10
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
Hydraflow Hydrographs Extension for AutoCADO Civil 31302009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 2.200 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
Q (cfs)
10.00
m
.M
4.00
2.00
I 8 of
BMP Post -Developed
Hyd. No. 2 -- 2 Year
8
Wednesday, Jan 13, 2021
Peak discharge = 9.808 cfs
Time to peak =
716 min
Hyd. volume =
20,884 cuft
Curve number
= 91.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
10.00
M
4.00
2.00
_I -_ 0.00
120 240 360 480 600 720 840 960 1080 1200
Hyd No. 2 Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
Post Through Pond
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Wednesday, Jan 13, 2021
= 0.000 cfs
= 1012 min
= 0 cuft
= 387.24 ft
= 10,393 cult
Q (cfs) Q (cfs)
Hyd. No. 3 -- 2 Year
10.00 10.00
8.00 8.00
6.00 6.00
4.00 4.00
2.00 2.00
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 1680
Time (min)
— Hyd No. 3 Hyd No. 2 Total storage used = 10,393 cult

10
Hydrograph Summary Re PQra-flow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph
No. type flow interval peak volume hyd(s) elevation strge used description
(origin) (cfs) (min) (min) (cuft) (ft) (cuft)
1
2
3
SCS Runoff
2.404
2
728
9,855
--
SCS Runoff
15.34
2
716
33,665
------
-----
Reservoir
0.000
2
728
0
2
388.37
BMP Pre -Developed
— BMP Post -Developed
17,381 Post Through Pond
Infiltration Trench#5.gpw Return Period: 10 Year Wednesday, Jan 13, 2021

11
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
2.200 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
120 240 360 480 600 720 840 960
Hyd No. 1
Wednesday, Jan 13, 2021
Peak discharge = 2.404 cfs
Time to peak
= 728 min
Hyd. volume
= 9,855 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (TO
= 21.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
3.00
2.00
1.00
0.00
1080 1200 1320 1440 1560
Time (min)

12
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
2.200 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
Q (cfs)
18.00
15.00
12.00
•M
. M
BMP Post -Developed
Hyd. No. 2 -- 10 Year
Wednesday, Jan 13, 2021
Peak discharge = 15.34 cfs
Time to peak
= 716 min
Hyd. volume
= 33,665 cuft
Curve number
= 91.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
18.00
15.00
12.00
M
1"Irk
0.00 0.00
0 120 240 360 480 600 720 840 960 1080 1200
Hyd No. 2 Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 3D® 2009 by Autodesk, Inc v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
15.00
12.00
Ism
. 11
K ert
0.00
0 240
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 10 Year
13
Wednesday, Jan 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 728 min
Hyd. volume
= 0 cult
Max. Elevation
= 388.37 ft
Max. Storage
= 17,381 cuft
480 720 960 1200 1440 1680
Hyd No. 2 Total storage used = 17,381 cuft
Q (cfs)
18.00
15.00
12.00
• W
M
3.00
0.00
1920
Time (min)

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INFILTRATION TRENCH #6

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #6
Drainage Area Lacres): 2.61
Existing Soil Groups:
Soil G/oU0 Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.61
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses.
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Open Space - Good Stand A 2.61
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #6
Drainage Area (acresZ 2.61
Existino Soil Groups:
Soil js2 UD May Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
2.61
100%
A/D Ra Rains Sandy Loam
0.00
0%
Pto posed Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Impervious Area -Residential Lots A 0.55
98
20.7
Impervious Area-Sidewalk/Road A 0.00
98
0.0
Open Space - Good Condition A 2.06
55
43.4
Cumulative Curve # =
64.1

Infiltration Trench Design
Site Information
Sub Area Location:
Drainage To Infiltration Trench 6
Drainage Area (DA) =
2.61 Acres 113711 sf
Impervious Area (IA) =
0.55 Acres 24000 sf
Percent Impervious (1) =
21.1 %
Required Water Quality Volume
Design Storm =
1 inch
Determine Rv Value =
0.05 + .009 (1) = 0.24 in/in
Water Quality Volume =
0.052 ac-ft
Water Quality Volume =
2,274 cf
Water Quality Volume =
0.240 inches of runoff
I OAA 1- ear. 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12'FS'DV)/(K'T)
Factor of Safety (FS) =
2
Design Volume (DV) =
2273.8 cf
Hydraulic Conductivity of Soil =
2.17 in/hr
Max Dewatering Time =
72 hours
SA Required =
349.3 sf
SA Provided =
530 sf

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xx

STAG EZ STO RAGE TABLE
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL
(FT) (FT) AREA (SF) STORAGE (CF) STORAGE (CF)
0.0
378.0
560
0
0
1.0
379.0
1290
925
925
2.0
380.0
2080
1685
2610 (WQv)
3.0
381.0
2925
2503
5113
4.0
382.0
3830
3378
8490
5.0
383.0
4790
4310
12800
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH 16
RIVER BASIN:
CAPE FEAR
RECEIVING STREAM:
MILL CREEK
STREAM INDEX:
18-31-11
STREAM CLASS:
C
HUC:
03030004
SCM DESIGN SUMMARY
DRAINAGE AREA TO SCM: 2.61 ACRES
SITE IMPERVIOUS AREA TO SCM: 0.55 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 0.55 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 2.61 AC 2.61 AC
CURVE NUMBER: 55 64.1
TIME OF CONCENTRATION: 12.7 MIN 5 MIN
1-YEAR STORM
EVENT:
0.247 CFS
1.935 CFS
0.000 CFS
2-YEAR STORM
EVENT:
0.922 CFS
3.434 CFS
0.000 CFS
10-YEAR STORM
EVENT:
4.093 CFS
8.377 CFS
0.000 CFS

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Pond Report s
Hydraflow Hydrographs Extension for AutoCADG Civil 3DO2009 byAutodesk, Inc. v6.066
Thursday, Mar 11, 2021
Pond No. 1
- BMP Pond
Pond Data
Contours - User -defined contour areas.
Average end
area method used for volume calculation. Begining Elevation = 378.00 ft
Stage / Storage Table
Stage (ft)
Elevation (ft)
Contour area (sgft)
Incr. Storage (cult) Total storage (cuft)
0.00
378.00
560
0 0
1.00
379.00
1,290
925 925
2.00
380.00
2,080
1,685 2,610
3.00
381.00
2,925
2,503 5,113
4.00
382.00
3,830
3,378 8,490
5.00
383.00
4,790
4,310 12,800
Culvert I Orifice Structures
Weir Structures
[A►]
[B]
[C]
[PrfRsr]
[A►] [B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft) = 0.00 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft) = 000 0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff. = 2.60 3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type = Broad ---
---
---
Length(ft)
= 0.00
0.00
0.00
0.00
Multi -Stage = No No
No
No
Slope (%)
= 0.00
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) = 2.170 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft) = 0.00
Stage (ft)
500
4.00
3.00
2.00
1.00
0.00 t - L-
0.00 0.03
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)
Stage / Discharge
0.06 0.09 0.12 0.15 0.18 0.21 0.24 0.27
Elev (ft)
383.00
382.00
381.00
380.00
379.00
378.00
0.30
Discharge (cfs)

Hyd rog ra p h Summary Re R13raflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
I Hydrograph
sed description
t)
i
BMP Pre -Developed
BMP Post -Developed
Post Through Pond
,day, Mar 11, 2021

`a
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
2.610 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
BMP Pre -Developed
Thursday, Mar 11, 2021
Peak discharge = 0.247 cfs
Time to peak =
726 min
Hyd. volume =
2,030 cuft
Curve number =
55
Hydraulic length =
0 ft
Time of conc. (Tc) =
12.70 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 1 Year
0.50 0.50
0.45 0-45
0.40 0.40
0.35 0.35
0.30 0.30
0.25 - 0.25
0.20 0.20
0.15 0.15
0.10 0.10
0.05 - � 0.05
0.00 _ ..._ — — — 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 1

3
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D®2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 2.610 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
1.00
BMP Post -Developed
Hyd. No. 2 -- 1 Year
120 240 360 480 600 720 840 960
Hyd No. 2
Thursday, Mar 11, 2021
Peak discharge = 1.935 cfs
Time to peak
= 718 min
Hyd. volume
= 4,392 cuft
Curve number
= 64.1
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
2.00
1.00
0.00
1080 1200 1320 1440 1560
Time (min)

4
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type =
Reservoir
Peak discharge
Storm frequency =
1 yrs
Time to peak
Time interval =
2 min
Hyd. volume
Inflow hyd. No. =
2 - BMP Post -Developed
Max. Elevation
Reservoir name =
BMP Pond
Max. Storage
Storage Indication method used. Exfiltration extracted from Outflow.
Q (cfs)
2.00
1.00
0.00
0 240
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 1 Year
480 720 960
Hyd No. 2
Thursday, Mar 11, 2021
= 0.000 cfs
= 1494 min
= 0 cult
= 379.54 ft
= 1,837 cuft
1200 1440 1680 1920 2160
Total storage used = 1,837 cuft
Q (cfs)
2.00
1.00
-11 0.00
2400
Time (min)

Hydrograph Summary Re Ry3rOow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
' Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
description
1
SCS Runoff
0.922
2
724
4,023
—
BMP Pre -Developed
2
SCS Runoff
3.434
2
718
7,179
-------
------
------
BMP Post -Developed
3
i
Reservoir
0.000
2
742
0
2
380.36
3,505
Thursday,
Post Through Pond
Infiltration
Trench#6.gpw
Return Period:
2 Year
Mar 11, 2021

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
7
Thursday, Mar 11, 2021
Peak discharge = 0.922 cfs
Time to peak =
724 min
Hyd. volume =
4,023 cuft
Curve number =
55
Hydraulic length =
0 ft
Time of conc. (Tc)
= 12.70 min
Distribution
= Type II
Shape factor
= 484
Time interval
= 2 min
Drainage area
= 2.610 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
BMP Pre -Developed
Q (cfs) Hyd. No. 1 -- 2 Year Q (cfs)
1.00 1.00
0.90 - - 0.90
0.80 - — - - 0.80
0.70 - 0.70
0.60 — 0.60
0.50 0.50
0.40 0.40
0.30 - 0.30
0.20 0.20
0.10 0.10
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
Hydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area T
2.610 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
Q (cfs)
4.00
am
2.00
1.00
BMP Post -Developed
Hyd. No. 2 -- 2 Year
120 240 360 480 600 720 840
Hyd No. 2
8
Thursday, Mar 11, 2021
Peak discharge = 3.434 cfs
Time to peak
= 718 min
Hyd. volume
= 7,179 cuft
Curve number
= 64.1
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
4.00
3.00
2.00
1.00
0.00
960 1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D@ 2009 by Autodesk, Inc. v6 066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
4.00
3.00
2.00
1.00
0.00
0 240
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 2 Year
480 720 960 1200 1440
Hyd No. 2
Thursday, Mar 11, 2021
Peak discharge = 0.000 cfs
Time to peak
= 742 min
Hyd. volume
= 0 cuft
Max. Elevation
= 380.36 ft
Max. Storage
= 3,505 cuft
Q (cfs)
4.00
3.00
K91111
1.00
0.00
1680 1920 2160 2400 2640
Total storage used = 3,505 cult Time (min)

10
Hydrograph Summary Re Ry?rdloow Hydrographs Extension for AutoCADO Civil 3D0 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
Time
interval
(min)
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
description
BMP Pre -Developed
1
SCS Runoff
4.093
2
722
r
11,845
------
--
—
2
SCS Runoff
8.377
2
718
16,769
-----
--
— -
BMP Post -Developed
3
Reservoir
0.000
2
770
0
I
Return Period:
2
10
382.33
Year
9,891
Post Through Pond
Mar 11, 2021
Infiltration
Trench#6.gpw
Thursday,

11
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 2.610 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.45 in
Storm duration
= 24 hrs
4.00
3.00
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
120 240 360 480 600 720 840
Hyd No. 1
Thursday, Mar 11, 2021
Peak discharge = 4.093 cfs
Time to peak
= 722 min
Hyd. volume
= 11,845 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 12.70 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
5.00
3.00
2.00
1.00
0.00
960 1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
2.610 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
M
M
S UR
BMP Post -Developed
Hyd. No. 2 -- 10 Year
120 240 360 480 600 720
Hyd No. 2
12
Thursday, Mar 11, 2021
Peak discharge = 8.377 cfs
Time to peak
= 718 min
Hyd. volume
= 16,769 cuft
Curve number
= 64.1
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
10.00
M
M
4.00
2.00
0.00
840 960 1080 1200 1320 1440 1560
Time (min)

13
Hydrograph Report
Hydraflow, Hydrographs Extension forAutoCAD® Civil 31382009 byAutodesk, Inc v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
Q (cfs)
10.00
M
M
W$
2.00
240 480 72
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 10 Year
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Thursday, Mar 11, 2021
= 0.000 cfs
= 770 min
= 0 cuft
= 382.33 ft
= 9,891 cuft
Q (cfs)
10.00
N. We
2.00
0.00
0 960 1200 1440 1680 1920 2160 2400 2640 2880 3120
Hyd No. 2 Total storage used = 9,891 cult Time (min)

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NFILTRATION TRENCH #7

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #7
Drainar,Le Area "acres 4.18
Existing Soil Groups:
Soil Grouo Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
4.18
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses:
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Open Space - Good Stand A 4.18
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #7
Drainage Area (acres): 4.18
Existing Soil Groups
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
4.18
100%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses:
Land Use Descr 6Q 2a Existing Soil Group Acres
Curve #
Weighted CN
Impervious Area -Residential Lots A 2.76
98
64.7
Impervious Area-Sidewalk/Road A 0.32
98
7.5
Open Space - Good Condition A 1.10
55
14.5
Cumulative Curve # =
86.7

Infiltration Trench Design
Site Information
Sub Area Location:
Drainage To Infiltration Trench 7
Drainage Area (DA) =
4.18 Acres 182260 sf
Impervious Area (IA) =
3.08 Acres 134033 sf
Percent Impervious (1) =
73.5 %
Required Water Quality Volume
Design Storm = I inch
Determine Rv Value = 0.05 + .009 (1) = 0.71 in/in
Water Quality Volume = 0.248 ac-ft
Water Quality Volume = 10,812 cf
Water Quality Volume = 0.712 inches of runoff
NOAA 1- ear. 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12'FS'DV)/(K'T)
Factor of Safety (FS) =
2
Design Volume (DV) =
10811.9 cf
Hydraulic Conductivity of Soil =
2.17 in/hr
Max Dewatering Time =
72 hours
SA Required =
1660.8 sf
SA Provided =
2355 sf

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'-STAGE/STORAGE TABLE
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL
(FT) (FT) AREA (SF) STORAGE (Cr) STORAGE (CF)
0.0
383.0
2355
0
0
1.0
384.0
4450
3403
3403
2.0
385.0
6610
5530
8933
3.0
386.0
8890
7750
16683 (WQv)
4.0
387.0
11415
10153
26835
5.0
388.0
14320
12868
39703
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH #7
RIVER BASIN: LUMBER
RECEIVING STREAM: BUFFALO CREEK
STREAM INDEX: 14-2.5
STREAM CLASS: c
HUC: 03040203
SCM DESIGN SUMMARY
DRAINAGE AREA TO SCM: 4.18 ACRES
SITE IMPERVIOUS AREA TO SCM: 3.08 ACRES
N IMPERVIOUS AREA TO 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 3.08 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 4.18 AC 4.18 AC
CURVE NUMBER: 55 86.7
TIME OF CONCENTRATION: 23 MIN 5 MIN
1-YEAR STORM EVENT:
0.288 CFS
12.30 CFS
0.000 CFS
2-YEAR STORM EVENT:
0.998 CFS
16.13 CFS
0.000 CFS
10-YEAR STORM EVENT:
4.568 CFS
26.74 CFS
0.000 CFS

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Pond Report s
Hydraflow Hydrographs Extension forAutoCAD® Civil 31382009 by Autodesk, Inc. v6.066
Thursday, Jan 14, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas. Average end area method used for volume calculation.
Begining Elevation = 383.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sqft)
Incr. Storage (cult)
Total storage (cuft)
0-00 383.00
2,355
0
0
1.00 384.00
4,450
3,403
3,403
2.00 385.00
6,610
5,530
8,933
3.00 386.00
8,890
7,750
16,683
4.00 387.00
11,415
10,153
26,835
5.00 388.00
14,320
12,868
39,703
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A]
[B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 000
0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00
0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff.
= 2.60
3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad
---
---
---
Length (ft)
= 0.00
0.00
0.00
0.00
Multi -Stage
= No
No
No
No
Slope (%)
= 0.00
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)
= 2.170 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
5.00
4.00
3.00
2.00
1.00
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)
388.00
387.00
386.00
385.00
384.00
0.00 - t. t r - 383.00
0.00 0.08 0.16 024 0.32 0.40 0.48 0.56 0.64 0.72 0.80
Total Q Discharge (cfs)

H yd rog ra p h Summary Re Ryar f ow Hydrographs Extension forAutoCAD® Civil 31302009 by Autodesk, Inc. v6.066
Hydrograph
description
eveloped
)eveloped
3h Pond
21

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 4.180 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
BMP Pre -Developed
Thursday, Jan 14, 2021
Peak discharge = 0.288 cfs
Time to peak
= 738 min
Hyd. volume
= 3,208 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 23.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Hyd. No. 1 -- 1 Year Q (cfs)
0.50 0.50
0.45 - — — 0.45
0.40 040
0.35 0.35
0.30 — 0.30
0.25 0.25
0.20 020
0.15 0.15
0.10 0-10
0.05 - 0-05
0.00 - _ — 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

3
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
4.180 ac
Basin Slope =
0.0 %
Tic method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
Q (cfs
14.00
12.00
10.00
Al
4.00
2.00
BMP Post -Developed
Hyd. No. 2 -- 1 Year
Thursday, Jan 14, 2021
Peak discharge = 12.30 cfs
Time to peak
= 716 min
Hyd. volume
= 25,027 cuft
Curve number
= 86.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
14.00
12.00
10.00
M
M
4.00
f�il�7
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440
Hyd No. 2 Time (min)

4
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31302009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
Q (cfs)
14.00
12.00
10.00
IX
. IX
18
r W
Post Through Pond
Hyd. No. 3 -- 1 Year
Thursday, Jan 14, 2021
Peak discharge = 0.000 cfs
Time to peak
= 680 min
Hyd. volume
= 0 cuft
Max. Elevation
= 385.74 ft
Max. Storage
= 14,629 cuft
Q (cfs)
14.00
12.00
10.00
A. We
A. We
4.00
2.00
0.00 1 ' , _ _ _ _ '- 0.00
0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880 3120
Hyd No. 3 Hyd No. 2 Total storage used = 14,629 cuft Time (min)

Hydrograph Summary Re Ry3rartw Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd.
No.
Hydrograph
type
(origin)
Peak
flow
(cfs)
0.998
Time
interval
(min)
2
Time to
peak
(min)
Hyd.
volume
(cuft)
Inflow
hyd(s)
Maximum
elevation
(ft)
Total
strge used
(cuft)
Hydrograph
description
BMP Pre -Developed
1
SCS Runoff
730
6,360
--
---
------
2
SCS Runoff
16.13
2
716
33,112
------
------
BMP Post -Developed
3
Reservoir
0.000
2
946
0
2
2 Year
386.33
20,029
Post Through Pond
Jan 14, 2021
Infiltration
Trench#7.gpw
Return Period:
Thursday,

Ire
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.180 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
BMP Pre -Developed
Thursday, Jan 14, 2021
Peak discharge = 0.998 cfs
Time to peak =
730 min
Hyd. volume =
6,360 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 23.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 1 -- 2 Year
1.00 1.00
0.90 0.90
0.80 0.80
0.70 0.70
0.60 0.60
0.50 - 0.50
0.40 0-40
0.30 0.30
0.20 0.20
0.10 -T 0.10
0.00 - - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

8
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 4.180 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
Q (cfs
18.00
15.00
12.00
• M
. M
3.00
BMP Post -Developed
Hyd. No. 2 -- 2 Year
Thursday, Jan 14, 2021
Peak discharge = 16.13 cfs
Time to peak
= 716 min
Hyd. volume
= 33,112 cuft
Curve number
= 86.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
18.00
15.00
12.00
IM1I11
. W
3.00
0.00 - - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
Hyd No. 2 Time (min)

9
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow.
15.00
12.00
• 11
. 11
i 11
240 480
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 2 Year
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
Thursday, Jan 14, 2021
= 0.000 cfs
= 946 min
= 0 cult
= 386.33 ft
= 20,029 cult
Q (cfs)
18.00
15.00
12.00
• 11
. /1
MWE
0.00
720 960 1200 1440 1680 1920 2160 2400 2640 2880
Hyd No. 2 Total storage used = 20,029 cult Time (min)

10
H yd rog ra p h Summary Re Ply?ra ow Hydrographs Extension for AutoCAD® Civil 3136 2009 by Autodesk, Inc. v6.066

11
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.180 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
4.00
3.00
2.00
1.00
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
Thursday, Jan 14, 2021
Peak discharge = 4.568 cfs
Time to peak
= 728 min
Hyd. volume
= 18,725 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 23.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
5.00
4.00
Of
2.00
1.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 4.180 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.45 in
Storm duration
= 24 hrs
BMP Post -Developed
12
Thursday, Jan 14, 2021
Peak discharge = 26.74 cfs
Time to peak
= 716 min
Hyd. volume
= 56,354 cuft
Curve number
= 86.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Q (cfs)
Hyd. No. 2 -- 10 Year
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 -- v -� 0.00
0 120 240 360 480 600 720 840 960 1080 1200
Hyd No. 2 Time (min)

13
Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD@ Civil 3D® 2009 by Autodesk, Inc v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Post Through Pond
Thursday, Jan 14, 2021
Peak discharge = 0.000 cfs
Time to peak
= 784 min
Hyd. volume
= 0 cult
Max. Elevation
= 387.70 ft
Max. Storage
= 35,905 cuft
Q (cfs) Hyd. No. 3 -- 10 Year Q (cfs)
28.00 I 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
0 360 720 1080 1440 1800 2160 2520 2880 3240
Time (min)
- Hyd No. 3 Hyd No. 2 Total storage used = 35,905 cult

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NFILTRATION TRENCH #8

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Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Pre -Developed Conditions #8
Drainage Area (acres Z 4.63
Existing Soil Groups.
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
0.00
0%
A CaB Candor Sand
4.63
100%
A/D Ra Rains Sandy Loam
0.00
0%
Existing Land Uses.
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Open Space - Good Stand A 4.63
55
55.0
Cumulative Curve # =
55.0

Triangle Site Design, PLLC
Timberland Ranch, Hoke County, NC
Curve Number Calculation (CN)
Post -Developed Conditions to Infiltration Trench #8
Drainage Area (acrejs 4.63
Existing Soil Groups:
Soil Group Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy Sand
4.63
100%
A CaB Candor Sand
0.00
0%
A/D Ra Rains Sandy Loam
0.00
0%
Proposed Land Uses.
Land Use Description Existing Soil Group Acres
Curve #
Weighted CN
Impervious Area -Residential Lots A 3.45
98
73.0
Impervious Area-Sidewalk/Road A 0.39
98
8.3
Open Space - Good Condition A 0.79
55
9.4
Cumulative Curve # =
90.7

Infiiltratian Trench Desian
Site Information
Sub Area Location:
Draina a To Infiltration Trench 7
Drainage Area (DA) =
4.63 Acres 201552 sf
Impervious Area (IA) =
3.84 Acres 167080 sf
Percent Impervious (I) =
82.9 %
Required Water Quality Volume
Design Storm =
1 inch
Determine Rv Value =
0.05 + .009 (1) = 0.80 in/in
Water Quality Volume =
0.307 ac-ft
Water Quality Volume =
13,371 cf
Water Qualitv Volume =
0.796 inches of runoff
NOAA 1- ear, 24-hour event = 3.05 inches
Minimum Surface Area (SA)
SA = (12•FS*DV)/(K*T)
Factor of Safety (FS) =
2
Design Volume (DV) =
13370.8 cf
Hydraulic Conductivity of Soil =
2.17 in/hr
Max Dewatering Time =
72 hours
SA Required =
2053.9 sf
SA Provided =
2375 sf

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'STAGE/STORAGE TABLE
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL
(FT) (FT) AREA (SF) STORAGE (CF) STORAGE (CF)
0.0
389.0
2375
0
0
1.0
390.0
4240
3308
3308
2.0
391.0
6170
5205
8513
3.0
392.0
8160
7165
15678 (WQv)
4.0
393.0
10205
9183
24860
5.0
394.0
12305
11255
36115
6.0
395.0
14460
13383
49498
STORMWATER MANAGEMENT DESIGN
INFILTRATION TRENCH 08
RIVER BASIN: LUMBER
RECEIVING STREAM: BUFFALO CREEK
STREAM INDEX: 14-2.5
STREAM CLASS: C
HUC: 03040203
DRAINAGE AREA TO SCM: 4.63 ACRES
SITE IMPERVIOUS AREA TO SCM: 3.84 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO SCM: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO SCM: 3.84 ACRES
PRE -DEVELOPED POST -DEVELOPED POST DEVELOPED
TO SCM TO SCM THROUGH SCM
DRAINAGE AREA: 4.63 AC 4.63 AC
CURVE NUMBER: 55 90.7
TIME OF CONCENTRATION: 21 MIN 5 MIN
1-YEAR STORM EVENT:
0.319 CFS
15.84 CFS
0.000 CFS
2-YEAR STORM EVENT:
1.106 CFS
20.12 CFS
0.000 CFS
10-YEAR STORM EVENT:
5.060 CFS
31.80 CFS
0.000 CFS

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Pond Report s
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Thursday, Jan 14, 2021
Pond No. 1
- BMP Pond
Pond Data
Contours - User -defined contour areas
Average end
area method used for volume calculation.
Begining Elevation
= 389.00 ft
Stage / Storage Table
Stage (ft)
Elevation (ft)
Contour area (sqft)
Incr. Storage (cuft)
Total storage (cuft)
0.00
389.00
2.375
0
0
1.00
390.00
4.240
3,308
3,308
2.00
391.00
6,170
5,205
8,513
3.00
392.00
8.160
7,165
15,678
4.00
393.00
10.205
9,183
24,860
5.00
394.00
12.305
11,255
36,115
6.00
395.00
14,460
13,383
49,498
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRSr]
[A] [B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 0.00 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 0.00 0.00
0.00
0.00
No. Barrels
= 0
0
1
0
Weir Coeff.
= 2.60 3.33
3.33
3.33
Invert El. (ft)
= 0.00
0.00
0.00
0.00
Weir Type
= Broad ---
---
---
Length (ft)
= 0.00
000
000
0.00
Multi -Stage
= No No
No
No
Slope (%)
= 0.00
0.00
0.00
n/a
N-Value
= .013
.013
.013
n/a
Orifice Coeff.
= 0.60
0.60
060
0.60
Exfil.(in/hr)
= 2.170 (by Contour)
Multi -Stage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
6.00
5.00
4.00
3.00
2.00
1.00
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)
39500
394.00
393.00
392.00
391 00
390.00
0.00 ' - ' - ' ' ' ' ' ' ' 389.00
0.00 0.08 0.16 0.24 0.32 0.40 0.48 0.56 064 0.72 0.80
Total Q Discharge (cfs)

H yd rog ra p h Summary Re Py3raflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066

2
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
4.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.05 in
Storm duration =
24 hrs
BMP Pre -Developed
Thursday, Jan 14, 2021
Peak discharge = 0.319 cfs
Time to peak
= 738 min
Hyd. volume
= 3,553 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 21.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs) Hyd. No. 1 -- 1 Year Q (cfs)
0.50 — 0.50
0.45 0.45
0.40 - 0.40
0.35 0.35
0.30 0.30
0.25 0.25
0.20 0.20
0.15 0.15
0.10 0.10
0.05 - 0.05
0.00 - 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
— Hyd No. 1 Time (min)

M
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 1 yrs
Time interval
= 2 min
Drainage area
= 4.630 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.05 in
Storm duration
= 24 hrs
Q (cfs)
18.00
15.00
12.00
M
M
3.00
BMP Post -Developed
Hyd. No. 2 -- 1 Year
Thursday, Jan 14, 2021
Peak discharge = 15.84 cfs
Time to peak =
716 min
Hyd. volume =
32,950 cuft
Curve number =
90.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
18.00
15.00
12.00
• We
M
3.00
0.00 " 0.00
0 120 240 360 480 600 720 840 960 1080 1200 1320
Hyd No. 2 Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADD Civil 3DO 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type =
Reservoir
Storm frequency =
1 yrs
Time interval =
2 min
Inflow hyd. No. =
2 - BMP Post -Developed
Reservoir name =
BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Post Through Pond
Peak discharge
Time to peak
Hyd. volume
Max. Elevation
Max. Storage
4
Thursday, Jan 14, 2021
= 0.000 cfs
= 2056 min
= 0 cult
= 392.50 ft
= 20,261 cult
Q (cfs) Q (cfs)
Hyd. No. 3 -- 1 Year
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 -w - 0.00
0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880 3120
Time (min)
Hyd No. 3 Hyd No. 2 Total storage used = 20,261 cult

Hyd rog raph Summary RePQra-flow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 31302009 byAutodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 2 yrs
Time interval
= 2 min
Drainage area
= 4.630 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.69 in
Storm duration
= 24 hrs
BMP Pre -Developed
Q (cfs)
Hyd. No. 1 -- 2 Year
2.00
1.00
120 240 360 480 600 720 840 960
Hyd No. 1
7
Thursday, Jan 14, 2021
Peak discharge = 1.106 cfs
Time to peak
= 730 min
Hyd. volume
= 7,044 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 21.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
2.00
1.00
0.00
1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc v6.066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
4.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.69 in
Storm duration =
24 hrs
18.00
15.00
12.00
• 11
. 11
3.00
0.00
0 120 240
— Hyd No. 2
BMP Post -Developed
Hyd. No. 2 -- 2 Year
8
Thursday, Jan 14, 2021
Peak discharge = 20.12 cfs
Time to peak
= 716 min
Hyd. volume
= 42,427 cuft
Curve number
= 90.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
21.00
18.00
15.00
12.00
• 11
. 11
MIX
0.00
360 480 600 720 840 960 1080 1200
Time (min)

Hydrograph Report
9
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
21.00
18.00
15.00
12.00
9.00
6.00
3.00
0.00
0 360 720
Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 2 Year
Thursday, Jan 14, 2021
Peak discharge = 0.000 cfs
Time to peak
= 594 min
Hyd. volume
= 0 cuft
Max. Elevation
= 393.17 ft
Max. Storage
= 26,744 cuft
Q (cfs)
21.00
18.00
15.00
12.00
M
M
r< I X
0.00
1080 1440 1800 2160 2520 2880 3240 3600
Hyd No. 2 Total storage used = 26,744 cult Time (min)

10
Hyd rog ra p h Summary Re Ryaraflow Hydrographs Extension for AutoCAD® Civil 3138 2009 by Autodesk, Inc. v6.066
Hydrograph
description
Pre -Developed
Post -Developed
Through Pond
2021

Hydrograph Report
11
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
BMP Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
4 Q1
4.00
3.00
a M
WI
BMP Pre -Developed
Hyd. No. 1 -- 10 Year
Thursday, Jan 14, 2021
Peak discharge = 5.060 cfs
Time to peak
= 728 min
Hyd. volume
= 20,740 cuft
Curve number
= 55
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 21.00 min
Distribution
= Type II
Shape factor
- 484
Q (cfs)
6.00
5.00
4.00
3.00
2.00
1.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Hyd No. 1 Time (min)

Hydrograph Report
12
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D@ 2009 byAutodesk, Inc. v6 066
Hyd. No. 2
BMP Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
4.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.45 in
Storm duration =
24 hrs
BMP Post -Developed
Hyd. No. 2 -- 10 Year
30.00
25.00
20.00
15.00
10.00
5.00
Thursday, Jan 14, 2021
Peak discharge = 31.80 cfs
Time to peak
= 716 min
Hyd. volume
= 69,127 cuft
Curve number
= 90.7
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00 1 ' - - ' ' 0.00
0 120 240 360 480 600 720 840 960 1080 1200
— Hyd No. 2 Time (min)

Hydrograph Report
13
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@ 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through Pond
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - BMP Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
30.00
25.00
20.00
15.00
10.00
5.00
0.00
0 360 720
— Hyd No. 3
Post Through Pond
Hyd. No. 3 -- 10 Year
Thursday, Jan 14, 2021
Peak discharge = 0.000 cfs
Time to peak
= 588 min
Hyd. volume
= 0 cult
Max. Elevation
= 394.71 ft
Max. Storage
= 45,672 cuft
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00
1080 1440 1800 2160 2520 2880 3240 3600 3960
Hyd No. 2 Total storage used = 45,672 cult Time (min)

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