SW6210702_Walters Meadow_20210803 (4)

Storm wafer Monagemenl Design Calculations
July 14, 2021
Walters Meadow
N. Horace Walters Road
Hoke County, NC
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
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TABLE OF CONTENTS
OVERVIEW
FIGURES
SOILS SURVEY INFORMATION
USGS MAP
FEMA FIRM MAP
8-DIGIT HUG
SURFACE WATER CLASSIFICATIONS
NOAA POINT PRECIPITATION FREOUENCY ESTIMATES
SHWT REPORT
WATER QUANTITY -INFILTRATION BASIN #1
DRAINAGE AREA MAP
DESIGN SUPPLEMENT
CN VALUES
PRE -DEVELOPMENT HYDROGRAFHS
POST -DEVELOPMENT HYDROGRAPHS
TIME VS. VOLUME (STORAGE)
TIME VS. ELEVATION (STAGE)
ELEVATION -VOLUME-FLOW SUMMARY
SCM SUMMARY
TIME OF CONCENTRATION
WATER QUANTITY -INFILTRATION BASIN #2
DRAINAGE AREA MAP
DESIGN SUPPLEMENT
CN VALUES
PRE -DEVELOPMENT HYDROCRAPHS
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 calculations for the proposed residential
development Walters Meadow on North Horace Walters Road in Hoke County. The project
site is currently un—developed area. The proposed site consists of 44.756 acres and
approximately 9.28 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 3710848400L
with an effective date of 7/7/14. Flood zones are subject to change by FEMA.
There are no existing stream or wetland features on the proposed property.
The proposed storm water management facilities (two
infiltration basins) outlined in this
report have been designed for post —development peak
attenuation to treat
the impervious
areas of
the development in Hoke County. Infiltration
Basin#1 is designed
to capture a
drainage
area of 25.74 ac with an impervious area of 7.36 cc. Infiltration
Basin#2 is
designed
to capture a drainage area of 7,63 ac with
an impervious area
of 2.12 ac. The
balance
of the site is open space and will by—pass the proposed SCMs.
The SCMs are
designed
to treat a 1.0" storm event.
Impervious Area Summery — Infiltration Basin #1
Road
90,490
2.077
Sidewalk
15,593
0.358
Lots @ 4 OOOsf lot
200 000
4.591
On -Site IA
306,08
7.02
(Off-site).14,629
0.34
Total IA to Pond
320,712
7.36
Impervious Area SummM — Infiltration Basin #2
Road
20,420
0.469
Sidewalk
3,655
0.084
Lots @ 4 OOOsf lot
68 000
1.561
Total IA to Pond
92,075
2.12
Soils
The County Soils Survey indicates that Autryville Loamy Sand soils are present on the site.

FIGURES

35' 045' N
35' 0' 16' N
Hydrologic Soil Group —Hoke County, North Carolina
64SWO G ':Lr 6.:OCC0 65 w r kMO 05=
3
N Map Scale: 1:4,410 If pdnted on A portrak (8.5" x 11') sheet.
N 0 50 100 200 300
Feet
0 200 400 800 1200
Map projection: Web Mermbr Corner moidrotes: WG584 Edge tics: U FM Zone 17N WGS84
35' 045'N
35' 016" N
Natural Resources Web Soil Survey
r� Conservation Service National Cooperative Soil Survey
6/18/2021
Page 1 of 4

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Hydrologic Soil Group —Hoke County, North Carolina
Hydrologic Soil Group
Map unit symbol I Map unit name Rating
AuA Autryville loamy sand, 0 A
Lto 2 percent slopes
Totals for Area of Interest
Description
Acres in AOI I Percent of AOI
43.81 100.0%
43.81 100.0%
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.
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.- None Specified
{p�pee� Natural Resources Web Soil Survey 6/18/2021
:ice Conservation Service National Cooperative Soil Survey Page 3 of 4

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6/21/2021 Precipitation Frequency Data Server
NOAA Atlas 14, Volume 2, Version 3
; USA'
Location name: Raeford, North Carolina1°
Latitude: 34.9799°, Longitude:-79.371
Elevation: 331.7 ft"
VVVrrr
€
• source: ESRI Maps
•• source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G M Bonnin, D Martin, B. Lin, T. Parcybok, M Yekta, and D Riley
NOAA, National Weather Service, Silver Spring, Maryland
PF tabular I PF graphical I Maps &aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Duration
Average
recurrence interval (years)
000
10
25
50
100
200
500
1000
0.436
0.515
0.601
0.665
0.743
0.799
0.852
0.902
0.965
1 1.01
5�rtin
0.398-0.481
0 470-0 567
0 548-0.662
0 605-0 731
(0.672-0 814)
0.721-0.875
i1:765.0.933
a.ao7-o.9g6
0.854-1.W
0.891-1.11
0.697
0.824
0.962
1.06
1.18
1.27
1.43
1.53
1.60
10{rlin
0.636-0.768
0 752-0 907
0 877-1 06
(0.967-1 17)
1 07-1 30)
1 15.1.39
71.36
1 22.1.A8
128-1 57
1.35-1 67
1.40-1 75
15{rlin
0,79 -0.959
0 946-11 14
(1.11-1 34)
1 223548)
(1 36--`1.65)
(1 45---1.76)
[1.54 1�67
1.6181t18
1,7092.11
1 60020)
30{nin
1.19
1.09-1 32)
1.43
(1.31-1.58)
1.73
(1 58-1 91
1.95
(1.77-2 14
2.22
(2 01-2.44
2.43
(2 19-2:M)
2.62
(2.35-2.87)
2.81
(2.51-3.08)
3.06 )
(2.71 3.35
( 3.24
2.85.3.56
474
60{rtin
(1 36--1964
1.6481o9b
2.02 2�44
2.31-279
2. 8--3624
2.97-3.60
324-3.95
3.52 4431)
3. 8-4 81
4. 5.19
2-hr
1 8 1$3
1.91 2034
2.40 2 94
.73703.39
3.25 4201
3.64 4 5D
4.01 4199
4. 995.d9
4-896917
6.08
5.26-6 72
1.84
2.23
2.81
3.28
3.92
4.45
4.99
5.57
6.38
7.03
3-hr
1 67-2.05
2.02-2.48
(255-3.13
2.96-3.64)
(3 52-4.35)
{3.9r-A.93
4.42-5.53]
(4.89-6 1fi)
5.53-7.05
[6.04-7 77)
6-hr
2.19
1 99-2 44
2.58
2.66
2,41-2.95
3.13
3.36
3.05-3.71
3.97
3.92
3 54-4 33
4.67
4.71
(4 22-5.19)
5.64
5.35
4.77 5:89
6.45
6.03
5.33.F.62
7.31
6.74
5,91-7 40
8.24
7.75
6.71-a.50
9.56
8.58
7.34-9.40
10.7
12-hr
2 34-2.88
2.84.3.48
9.59-4.42
( 421.5,1 B
5 04-6 24)
5.73.7.12)
6.43-8.06
16-9 07
8.19-10.5
9.00.11 7
3.06
3.70
4.68
5.46
1 6.54 11
7.40
8.30
9.22
10.5
11.5
24-hr
2.83.331]
(3.43.4.00)
(4.33.5.06)
(5.04-5-00)
601-706)
(G79-7.99)
y
(7.58.8.96)
( 8.40-996
9.5311A
( 10.4.125)
3.55
4.29
5.38
6.25
7.45
8.41
9.41
10.4
11.9
13.0
2�ay
[3.31.3.82)
(3.99.4.151)
(5.005.8p)
5,80-6.73
6.88-8.01
7.75-9.06 )
( 8.63-10,1)
(9,54-11.2 )
( 10 6-12.8 ]
( 11 7-14.0
7-4
3 day
2
3.52 4704
4.244.87
5. 9-6:07
6' l-T63
(7.23-8-M
8. 9941
(9. 410.5)
l9.97.--111.7
(11 2-13.
122-14.5
3.99
4.80
5.96
6.88
8.15
9.17
10.2
11.3
12.8
14.0
4�iay
3.74-4.26
4.49-15.12
5.57.6.35
(6 42-7.33)
1 (7.58-8.69)
8.50.9.77
(9.44-10:9]
10.4-12 1
11 7-13 7
[12.7-15.0
4.62
5.52
6.78
7.77
9.14
10.2
11.4
12.5
14.1
15.4
flay
(4.33-4.93)
(5.17-5.90)
(6.34.7.24)
t7.26-8.30)
(8 51-9.75)
(S3.50-10.9)
[ 10.5-12.1) 11
(11 5-13 4)
(12 9-15.1)_
[ 14 0-16.5
10�ay
(4.993.62
(5 5 6170
7 868.09
8. 5 69.18
9 49 10.7
1¢14 1.8
11 4-132
12.4- 4.2
1318-15.9
1419-17.2
20-day
7.11
6,73-7.53
8.42
7 97-8 91
10.0 )
9 45-10 6
11.3
10.6-11 9
( 12.9 )
12 2-13 7
14.3
73 4-15.1
15.6
14 6-16.5
16.9
15 8-17 9
18.8
17 4-19.9
20.2
18 7-21.4)
30 day
8.83
10.4
12.2
13.5
15.3
16.7
18.1
19.4
21.2
22.6
(837-9 34
9 87-11.0
(11 5-12 9
12.8-14 3 )
14 5-16 2
75 7-17,8
17.0-19.1
18.2-20 5
(19.8-22.5)
21 1.24.1
11.2
-13.71-71
15.1
16.6
18.5
20.0
21.4
22.9
24.7
26.1
45�ay
(10 6 11.8
(12.4-13.8
(14 3-15.9)
(15.7-17.5)
17.5-19 5)
19.9-21.1)
1 (21.5-24 2)
(232.26:2)
(24.5-27
60�1ay
771
9.15
6-
98
1273 4.1
149--16.5)
1619- 8.8
18 0.5
2 5122 7
220 4.4
23.4 6.1
2A 8-27 7
26.E-29.8
2729--31.5
t 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
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
of checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical
https://hdsc. nws.noaa.gov/hdsc/pfds/pfds_printpage. html?lat=34.9799&Ion=-79.3711 &data=depth&units=eng lish&series=pds 1 /4

Scott Cole, NCLSS
312 Copples Road E.rt
Asheboro, NC 27205
[phone]
Double D Engineering, PLLC
Attn: Mr. Lee Humphrey
150 S. Page Street
Southern Pines, NC 28387
June 7, 2021
Re: Seasonal High -Water Table Identification and Soil Infiltration Rates: Walters Meadow; Hoke
County NC Parcels (Altparno) 4755 (N. Horace Walter Road)
Soil conditions and infiltration rates were evaluated and measured on the above -referenced property
within the proposed storm water BMP device. Work was conducted in accordance with Parts A-2 and C-
1 of the North Carolina Department of Enviromnental Quality Stormwater Design Manual. Soil samples
were evaluated with a hand auger.
SEASONAL HIGH WATER TABLE IDENTIFICATION
Seasonal High Water Table depth is determined by field evaluation for soil wetness conditions which are
indicated by the presence of redoximorphic (redox) features with a chroma of 2 or less (in Munsell color
notation) in mottles or the horizon matrix. Colors of chroma 2 or less due to relic minerals from parent
material (underlying rock), anaerobic activity created by placement of fill material, or soil textural class
transitions (perched water) are not considered as indicators for seasonal high water. Upon determination
of SHWT depth, an additional 6" will be deducted from the observed depth to account for capillary fringe
water movement above the SHWT. Stormwater infiltration trenches are designed to ensure the lowest
point is at least two feet above the Seasonal High Water Table (Sl IWT).
SATURATED HYDRAULIC COND1JCTIV1TY KY„
Soils evaluated across most of this property are typical of those within the Autryville Loamy Sand series
(AuA). These are deep, well drained soils with varying rates of permeability. However, soils within the
proposed stormwater BMP devices are shallow to damp/saturated soil conditions as well as expansive
clay mineralogy. Infiltration rates were measured to determine if soil conditions were suitable for the
installation of stormwater infiltration trenches. Infiltration rates were measured using a Johnson Constant
Head Permeameter. Measurements were recorded at varying intervals until equilibrium was reached.
A summary of observations within the proposed Stormwater BMP Device is shown in the table below.
BW Device Site #1
SHWT
(inches below
round surface
Munsell Color
Notation
Ksat
(48"; SL)
60" (5') (SHWT
elevation 355')
2.5Y 8/1
8.7" / hour
Saturated soil
2.5Y 7/1
conditions
observed at 60"
bs

Scott Cole, NCLSS
312 Copples Road Ext
Asheboro, NC 27205
[phone]
BMP Device Site #2
SHWT
(inches below
round surface
Munsell Color
Notation
Ksat
(18"; SL/SCL)
24" (2') (SHWT
elevation 358')
2.5Y 8/1
5.5" / hour
Gleyed soil
2.5Y 7/1
conditions /
heavy expansive
—clay at 24" b s
CONCLUSION
Field evaluation of hydraulic conductivity provides estimations of soil infiltration rates; however,
methods used to measure these rates can influence the results. Side walls of the bore hole are "smeared"
by the soil auger as the hole is prepared and loose soil in the bottom of the hole is placed in suspension
when water is applied; both of these factors negatively influence water infiltration rates. To help
overcome these issues, after excavation of each infiltration trench, it is recommended the trench bottom
and sidewalls be raked and dusted with pulverized limestone. These are practices that have been in place
within the on -site wastewater industry to help loosen the soil and aid in restoration of soil structure.
1 am pleased to be of service in this matter and can be contacted at your convenience should you have any
questions concerning information within this report.
Thank you,
Scott Cole
North Carolina Licensed Soil Scientist
aou
1�
ikA

.3. lAed-!!
'k CV
CO
inch = 250 feet-
BIVIP Site #1
SHWP 60" (5') bgs
SHWT Elevation: 355'
Ksat 048" SL: 8.7" I hour
1 M shp t
�-p 2SIAG sat shwt
BMP Site #2
SHVM. 24" (2) bgs
SHWr Elevation: 358'
Ksat 0.24" SUSCL-. 5.5" hour
+
cod e m nument cor
81 � 2sl eo c -gleyed
45s1 exp vy t.
IT

WATER QUANTITY -INFILTRATION BASIN#1

c
m

SUPPLEMENT-EZ COVER PAGE
LOAD SUPPLEMENT FORMS
PROJECT INFORMATION
1
Project Name
Walters Meadow
2
Project Area ac
44.756
-
High
No
3
Coastal Wetland Area (ac)
4
Surface Water Area (ac)_
5
Is this project High or Low Density?
6
fDoes this project use an off -site SCM?
COMPLIANCE WITH 02H.1003(4)
7
Width of vegetated setbacks provided feet
NIA
8
Will the vegetated setback remain vegetated?
NIA
9
If BUA is pro2osed in the setback does it meet NCAC 02H.1003 4 c-d ?
No
10
Is streambank stabilization proposed on this project?
No
NUMBER AND TYPE OF SCMS'
11
Infiltration S stem
2
12
Bioretention Cell
0
0
13
Wet Ppnd
Stormwater Wetland
14
0
15
Permeable Pavement
0
16
Sand Filter
0
17
Rainwater Harvesting (RWH)
0
18
Green Roof
0
19
Level Spreader -Filter Strip (LS-FS)
0
20
Disconnected Impervious Surface (DIS)
0
21
Treatment Swale
0
22
Dry Pond
0
23
StormFilter
0
24
Silva Cell
0
25
Bayfilter
0
26 1
Filterra
0
LOAD SUPPLEMENT FORMS
[DESIGNER CERTIFICATION
27
Name and Title:
Organization:
Carla Pardo, PE
28
Triangle Site_Design PLLC _
29
Street address:
4004 Barrett Drive, Suite 101
30
City, State Zip:
Raleigh, NC 27609
31
Phone numbers :
919-553-6570
32
Email:
[e-mail]
Certification Statement
I certify, under penalty of law that this Supplement-FZ form and all supporting information were prepared under my direction or supervision; that the
information provided in the form is, to the best of my knowledge and belief, true, accurate, and complete; and that the engineering plans,
specifications, operation and maintenance agreements and other supporting information are consistent with the information provided here.
A Roe��l�rr
SEAL
05157
z'
�IN,,. E'
rrrfJC,.RC NO..E . �Q�ti��
��If t tlb�i►t�1
-(I
Signature of Designer
Date

DRAINAGE AREAS
1
Is this a hi h dens ity r9ject?
Yes
2
If so, number of drainage areas/SCMs
2
3
Does this project have low density areas?
No
4
If so, number of low density drainage areas
0
5
Is all/part of this project subject to previous rule
versions?
No
FORMS LOADED
DRAINAGE AREA INFORMATION
Entire Site
1
2
4
Type of SCM
-
Infiltration Basin
Infiltration Basin
5
Total drainage area (sq ft
1453395 sf
1121013
332382
6
Onsite drainage area (sq ft
1438766 sf
1106384
332382
7
Offsite drainage area (sq ft
14629 sf
14629
8
Total BUA in project (sq ft
412787 sf
320712 sf
92075 sf
9
New BUA on subdivided lots (subject to permitting)
(sq ft
10permitting)
New BUA not on subdivided lots (subject to
s
11
Offsite BUA (sq ft
_
14629 sf�
14629 sf
12
Breakdown of new BUA not on subdivided lots:
Parkin (sq ft
Sidewalk (sq ft
19248 sf
15593 sf
3655 sf
Roofsq ft
268000 sf
200000 sf
68000 sf
-Roadway s ft_)
Future (sq ft)
1.10910 sf
90490 sf
20420 sf
- Other, please specify in the comment box
below (sq ft
13
New infiltrating permeable pavement on
subdivided lots (sq ft
14
New infiltrating permeable pavement not on
subdivided lots (sq ft
15permitting)
Existing BUA that will remain (not subject to
s ft
16
Existin2 BUA that is already permitted (sq ft
17
Existing BUA that will be removed (sq ft
18
Percent BUA
29%
28%
19
Design storm (inches)
1.0 in
1.0 in
20
Desi n volume of SCM cu ft
28730 cf
8291 cf
21
Calculation method for design volume
Simple Method
Simple Method
RONAL WORMATION _ J
Please use this space to provide any additional information about the
22 drainage area(s):
Infiltration Basin #1 - there is offsite drainage area that is being accounted for
at its full build -out potential (100% BUA)

INFILTRATION SYSTEM[
1 ]Drainage area number 1 2
2 Minimum required treatment volume cu ft
28730 cf 8291 cf
GENERAL MDC FROM 02H .1050
3
Is the SCM sized to treat the SW from all surfaces at build -out?
Yes
Yes
4
Is the SCM located away from contaminated soils?
Yes
Yes
5
What are the side slopes of the SCM (H:V or enter "Vertical" for
trenches)?
3:1
3:1
6
Does the SCM have retaining walls, gabion walls or other engineered
side slopes?
No
No
7
Are the inlets, outlets, and receiving stream protected from erosion
10-yea r storm)?
Yes
Yes
8
Is there an overflow or bypass for inflow volume in excess of the
design volume?
Yes
Yes
9
What is the method for dewatering the SCM for maintenance?
Pump (preferred)
Pump (preferred)
10
If applicable, will the SCM be cleaned out after construction?
Yes
Yes
11
Does the maintenance access comply with General MDC (8)?
Yes
Yes
12
Does the drainage easement comply with General MDC (9)?
Yes
Yes
13
If the SCM is on a single family lot, does (will?) the plat comply with
General MDC 10 ?
NIA
N/A
14
Is there an O&M Agreement that complies with General MDC (11)?
Yes
Yes
15
Is there an O&M Plan that complies with General MDC (12)?
Yes
Yes
16
Does the SCM follow the device specific MDC?
Yes
Yes
17
lWas the SCM designed bX an NC licensed erofessional?
Yes
Yes
imr.n TR&1nn11 CVMT- A MnC FRiaM n214 1651
18
Proposed slope of the suhgrade surface (°/.)
0%
0%
19
Are terraces or bafflesprovided?
No
No
20
IType of pretreatment:
I Forebay
Forebay
21
Was the soil investigated in the footprint and at the elevation of the
infiltrations stem?
Yes
Yes
22
SHWT elevation (fmsl)
355.00
358.00
23
Depth to SHWT per soils report (in)
60.00
24.00
24
Ground elevation at boring in soils report (fmsl)
360.00
360.00
25
Is a detailed hydrogeologic study attached if the separation is
between 1 and 2 feet?
Yes
Yes
26
Soil infiltration rate (in/hr)
4.50
3.00
27
1 Factor of safe F5 2 is recommended):
2.00
2.00
I Fl—H.nc
29
Bottom elevation fmsl
357 ft
360 ft
30
IStorage elevation (fmsl)
358. ft
361. ft
31
1 Bypass elevation (fmsl)
360.1 ft
362.7 ft
For Basins Only_
32 Bottom surface area (ft 2) 34050 ft 11385 ft
33 Storage elevation surface area ft' 36150. ft 12740. ft
Fnr Trane-hac r)n/v
34
Length (ft)
35
Width (ft)
36
Perforated pipe diameter, if applicable (inches)
37
Number of laterals
38
Total length of perforated piping
39
Stone type, if applicable
40
Stone porosity
41
Is stone free of fines?
42
Is the stone wrapped in geotextile fabric?
43
Has at least one Inspection port been provided?
vowines/DraWdown
44 IDesign volume of SCM (cu ft) 28730 cf 8291 cf
45 1 Time to draw down (hours) 72 hrs 72 hrs
ADDITIONAL INFORMATION
46 Please use this space to provide any additional information about the
(infiltration system(s):
Infiltration 1 4:45 PM 7/13/2021

Triangle Site Design, PLLC
Hoke, NC
Curve Number Calculation (CN)
Pre -Developed Conditions
Drainage Area (acresZ 25.74
Existing Soil Groups:
Soil Grow Map Symbol Soil Description Acres Percent of DA
A AuA Autryville loamy sand 25.74 100%
Existing Land Uses:
Land Use Description Existing Soil Group Acres Curve # Weighted CN
Open Space - Good Condition A 19.06 60 44.4
Wooded - Good Stand A 6.68 54 14,0
Cumulative Curve # = 58.4

Triangle Site Design, PLLC
Curve Number Calculation
(CN)
Post -Developed Conditions
Drainage Area (acres Z 25.74
Existing Soil Groups:
Soil Grow Map Symbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy
Sand
25.74
100%
Proposed Land Uses:
Land Use Description Existing Soil_ Group
Acres
Curve #
Wehghted CN
Impervious Area A
7.36
98
28.0
Open Space - Good Condition A
18.38
60
42.8
Cumulative Curve # =
70.9

Infiltration Basin Design
Site Information
Sub Area Location:
Drainage To Infiltration Basin #1
Drainage Area (DA) =
25.74 Acres 1121013 sf
Impervious Area (IA) =
7.36 Acres 320712 sf
Percent Impervious I =
28.61 %
Required Water Quality Volume
Design Storm = 1 inch
Determine Rv Value = 0.05 + .009 (1) = 0.31 in/in
Water Quality Volume = 0.660 ac-ft
Water Quality Volume = 28,730 cf
Water Quality Volume = 0.307 inches of runoff
I NOAA 1-year, 24-hour event = 3.06 inches
Minimum Surface Area
SA =
(12-FS-DV)/(K"T)
Factor of Safety (FS) =
2
Design Volume (DV) =
28730.0 cf
Hydraulic Conductivity of Soil =
4.50 in/hr
Max Dewatering Time =
72 hours
SA =
2128.1 sf

\ 1
/

STAG EZSTO RAGE TABLE
INFILTRATION BASIN
STAGE
ELEVATION
CONTOUR
INCREMENTAL
TOTAL
(FT)
FT
AREA SF
STORAGE CF
STORAGE CF
0.0
357.0
34050
0
0
1.0
358.0
36150
35100
35100
2.0
359.0
38320
37235
72335
3.0
360.0
40535
39428
111763
4.0
361.0
42810
41673
153435
5.0
362.0
45145
43978
197413
STORMWATER MANAGEMENT DESIGN
INFILTRATION BASIN
RIVER BASIN:
RECEIVING STREAM:
STREAM INDEX:
STREAM CLASS:
HUC:
LUMBER
BUFFALO CREEK
14-2.5
C
03040203
POND DESIGN SUMMARY
DRAINAGE AREA TO POND:
25.74 ACRES
SITE IMPERVIOUS AREA TO POND: 7.02 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO POND: 0.34 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO POND: 7.36 ACRES
DRAINAGE AREA:
CURVE NUMBER:
INFILTRATION RATE:
PRE -DEVELOPED
25.74 AC
58.4
POST -DEVELOPED
25.74 AC
70.9
4.5 IN/HR
POST DEVELOPED
THROUGH POND
1.0" STORM EVENT:
0.136
CFS
0.000
1-YEAR STORM EVENT:
3.237
CFS
33.94
CFS
0.000
2-YEAR STORM EVENT:
7.967
CFS
51.83
CFS
0.000
10-YEAR STORM EVENT:
28.20
CFS
107.12
CFS
0.000
100-YEAR STORM EVENT:
71.93
CFS
207.83
CFS
51.59
CFS
CFS
CFS
CFS
CFS

s
Ifi
4330 A 0 U44
d
H
U
tW/1
Z
N

7
Hydrograph
Report
Hydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Hyd. No. 3
Post Through SCM
Hydrograph type
= Reservoir
Peak discharge =
51.59 cfs
Storm frequency
= 100 yrs
Time to peak =
12.07 hrs
Time interval
= 2 min
Hyd. volume =
149,897 cuft
Inflow hyd. No.
= 2 - SCM Post -Developed
Reservoir name =
BMP Pond
Max. Elevation
= 361.68 ft
Max. Storage =
183,281 cuft
Storage Indication method
used. Exfiltration extracted from Outflow.
Hydrograph Discharge Table
(Printed values >=100%ofOp)
Time Inflow Elevation Clv A Clv B Clv C
PfRsr
Wr A Wr B Wr C
Wr D Exfil
Outflow
(hrs) cfs
ft cfs cfs cfs
cfs
cfs cfs cfs
cfs cfs
cfs
11.93 207.83 <<
360.42 ----- ----- --
-----
4.726 ----- -_ -
----- 4.322
4.726
11.97 204.53
360.96 ----- _ -----
-----
20.90 ----- -----
----- 4.451
20.90
12.00 162.61
361.37 ----- ----- -----
-----
37.44 ----- -----
----- 4.550
37.44
12.03 103.31
361.61 ----- ----- -----
- --
48.17 ----- - -
----- 4.607
48.17
12.07 57.28
361.68 << ----- ----- -----
------
51.59 ----- - --
- -- 4.624
51.59 <<
12.10 35.74
361.65 ---- _- - -
-
50.38 ----- -- -
----- 4.618
50.38
12.13 29.41
361.60 - - -- - -
- --
47.60 ----- -----
----- 4.604
47.60
12.17 28.22
361.54 ----- ----- -----
- -
44.78 ----- -----
----- 4.590
44.78
12.20 27.08
361.48 ----- ----- -----
-
42.20 ----- --- -
----- 4.576
42.20
12.23 25.93
361.43 ----- -----
-----
39.84 ----- -----
----- 4.564
39.84
12.27 24.78
361.38 -- -- -
---
37.65 ----- -----
----- 4.552
37.65
12.30 23.61
361.33 --- ----- -----
-----
35.63 ----- -- --
- 4.540
35.63
12.33 22.43
361.29 ----- ----- -----
-----
33.73 ----- -----
--- 4.530
33.72
12.37 21.25
361.25 --- ----- -----
-----
31.95 ----- -- -
---- 4.519
31.95
12.40 20.06
361.21 ----- -----
- ---
30.25 ----- -----
----- 4.509
30.25
12.43 18.86
361.17 ----- ----- -----
-----
28.65 ----- -----
----- 4.500
28.65
12.47 17.65
361.13 ----- ----- ----
-----
27.11 ----- -----
--- 4.490
27.11
12.50 16.44
361.09 ----- ----- ----
---
25.63 ----- ----
--- 4.481
25.63
12.53 15.32
361.05 ----- ----- ----
-----
24.23 ----- -----
----- 4.472
24.23
12.57 14.48
361.02 ----- ---- ---
-----
22.87 ----- -----
----- 4.464
22.87
12.60 13.96
360.98 ----- ----- -----
-----
21.57 ----- -----
----- 4.455
21.58
12.63 13.63
360.95 ----- ----- ---
-----
20.37 -- - - --
----- 4.447
20.37
12.67 13.36
360.92 ----- ----- -----
----
19.26 ----- -----
----- 4.440
19.26
12.70 13.09
360.89 ----- ----- -----
---
18.25 ----- -----
----- 4.433
18.25
12.73 12.82
360.86 - - -
--
17.35 ----- -----
----- 4.427
17.35
12.77 12.55
360.84 - -- ----- -----
- --
16.51 ----- -----
----- 4.421
16.51
12.80 12.28
360.81 ----- ----- -----
-----
15.72 ----- -- -
- - - 4.415
15.72
12.83 12.00
360.79 - ----- -----
-----
14.99 ----- -----
----- 4.410
14.99
12.87 11.73
360.77 - ---- - -
-----
14.34 ----- --
----- 4.405
14.34
12.90 11.45
360.75 ----- ----- --
-----
13.72 ----- -----
----- 4.401
13.72
12.93 11.18
360.73 ----- ----- -
---
13.13 ----- -----
----- 4.396
13.13
12.97 10.90
360.72 ----- -- -----
-----
12.57 ----- ---
_ -- 4.392
12.57
13.00 10.62
360.70 ----- ----- -----
-----
12.04 ----- -----
- -- 4.388
12.04
13.03 10.36
360.68 ----- ----- --
-----
11.56 ----- -----
- -- 4.384
11.56
13.07 10.13
360.67 -- --- - -
---
11.11 ----- -----
----- 4.380
11.11
13.10 9.947
360.65 - - --- --- -
-----
10.67 ----- -----
----- 4.377
10.67
13.13 9.790
360.64 ----- ----- -----
---
10.26 ----- -----
- -.... 4.373
10.26
13.17 9.642
360.62 ----- ----- -----
-- -
9.864 ----- - - -
----- 4.370
9.864
13.20 9.494
360.61 ---- - -
--
9.491 ----- --
----- 4.367
9.491
13.23 9.345
360.60 ----- - - --
----
9.141 ----- -----
----- 4.364
9.142
Continues on next page...

1.1
Post Through SCM
Hydrograph Discharge Table
Time
Inflow
Elevation
Clv A Clv B
Clv C PfRsr Wr A
Wr B Wr C Wr D
Exfil
Outflow
(hrs)
cfs
ft
cfs cfs
cfs cfs cfs
cfs Cfs cfs
cfs
cfs
13.27
9.196
360.59
----- -----
----- ----- 8.834
----- ----- -----
4.361
8.834
13.30
9.047
360.58
----- -----
----- ----- 8.539
----- ----- -----
4.359
8.539
13.33
8.897
360.56
--- -----
----- ----- 8.254
----- ----- -----
4.356
8.254
13.37
8.747
360.55
----- ____
_.-__ w___ 7.979
----- ----- -----
4.354
7.979
13.40
8.596
360.54
----- -----
----- ----- 7.714
----- ----- ----
4.351
7.714
13.43
8.446
360.53
----- -----
----- ----- 7.457
----- ----- -----
4.349
7.456
13.47
8.295
360.52
----- -__-
_ _- _ 7.207
----- ----- -----
4.347
7.207
13.50
8.143
360.51
---- -----
--- - ----- 6.965
----- ----- -----
4.344
6.965
13.53
7.997
360.51
----- -----
----- ----- 6.731
----- ----- -----
4.342
6.730
13.57
7.863
360.50
----- -----
----- ----- 6.511
----- ----- -----
4.340
6.511
13.60
7.743
360.49
----- -- --
----- ----- 6.315
----- ---- -----
4.338
6.315
13.63
7.633
360.48
----- -----
----- ----- 6.124
----- ---- -----
4.336
6.125
13.67
7.525
360.47
----- -----
_---- ----- 5.939
----- ----- -----
4.334
5.940
13.70
7.417
360.46
----- -----
----- ----- 5.759
----- ---- -----
4.332
5.759
13.73
7.309
360.46
----- -----
- ----- 5.584
---- ----- -----
4.331
5.584
13.77
7.200
360.45
----- -----
----- ----- 5.413
----- ---- -----
4.329
5.413
13.80
7.092
360.44
----- -----
----- - 5.246
----- ----- -----
4.327
5.247
13.83
6.983
360.44
----- -----
-- - 5.084
----- ---- -----
4.325
5.084
13.87
6.874
360.43
---- -----
-- ----- 4.924
----- ----- -----
4.324
4.924
13.90
6.765
360.42
----- -----
-- ----- 4.768
----- --- -----
4.322
4.768
13.93
6.656
360.41
----- ----
--- --- 4.615
----- ----- -----
4.321
4.615
13.97
6.547
360.41
----- -----
----- --- 4.465
----- --- ----
4.319
4.465
14.00
6.437
360.40
- - ---
--- ----- 4.318
----- ----- -----
4.318
4.318
14.03
6.335
360.40
---- -
-- - 4.189
----- -- ----
4.316
4.189
14.07
6.254
360.39
----- -----
----- ----- 4.068
----- ----- -----
4.315
4.068
14.10
6.198
360.38
---- ----
----- ----- 3.951
----- ----- -----
4.313
3.950
14.13
6.156
360.38
----- -----
----- ----- 3.837
----- ----- -----
4.312
3.837
14.17
6.119
360.37
---- ---
----- - --- 3.727
----- ----- -----
4.311
3.727
14.20
6.082
360.37
----- -----
----- ----- 3.621
----- ----- -----
4.309
3.621
14.23
6.045
360.36
----- -----
----- ----- 3.520
----- ----- -----
4.308
3.520
14.27
6.008
360.36
----- -----
----- ---- 3.421
---- ---- -----
4.307
3.421
14.30
5.971
360.35
---- -----
----- ----- 3.327
----- ----- -----
4.306
3.327
14.33
5.933
360.35
----- __.__
____ _____ 3.235
----- ----- -----
4.305
3.235
14.37
5.896
360.34
----- _____
_ _ _____ 3.146
----- ---- -----
4.303
3.146
14.40
5.859
360.34
----- -----
----- ----- 3.061
----- ----- -----
4.302
3.061
14.43
5.821
360.33
----- -----
----- ---- 2.977
----- ----- -----
4.301
2.978
14.47
5.784
360.33
--- -----
----- _-_.. 2.897
----- _.. _._._
4.300
2.897
14.50
5.747
360.33
----- -----
----- ----- 2.819
----- -- -- -----
4.299
2.819
14.53
5.709
360.32
--_-- -----
----- ----- 2.743
----- ---- -----
4.299
2.743
14.57
5.671
360.32
----- -----
----- ----- 2.670
----- ----- -----
4.298
2.670
14.60
5.634
360.31
----- -----
----- ----- 2.598
----- ---- -----
4.297
2.598
14.63
5.596
360.31
- - -----
----- ----- 2.528
----- ----- -----
4.296
2.528
14.67
5.559
360.31
----- -----
----- ----- 2.460
----- ----- -----
4.295
2.460
14.70
5.521
360.30
---- ----
-- --- 2.394
----- ----- ----
4.294
2.394
14.73
5.483
360.30
----- .---_
_ ___ ___._ 2.329
----- ----- ___
4.294
2.329
14.77
5.445
360.30
----- -----
----- ----- 2.279
----- ----- -----
4.293
2.279
14.80
5.407
360.29
----- -----
----- ----- 2.231
---- ----- -----
4.292
2.231
14.83
5.369
360.29
----- -----
_---- ----- 2.183
----- ----- -----
4.291
2.183
14.87
5.331
360.29
----- -----
----- ---- 2.135
----- ----- ----
4.290
2.135
14.90
5.293
360.28
----- -----
----- ----- 2.088
----- ----- -----
4.290
2.088
14.93
5.255
360.28
----- -----
----- ----- 2.041
----- ----- ----
4.289
2.041
14.97
5.217
360.28
----- -----
----- ----- 1.995
----- ----- -----
4.288
1.995
15.00
5.179
360.27
----- -----
----- ----- 1.949
----- ----- -----
4.288
1.949
Continues on next page...

PI
Post Through SCM
Hydrograph Discharge Table
Time
Inflow
Elevation
Clv A Clv B Clv C PfRsr
Wr A
Wr B Wr C Wr D
Exfil
Outflow
(hrs)
cfs
ft
cfs cfs cfs cfs
cfs
cfs cfs cfs
cfs
cfs
15.03
5.141
360.27
----- ----- --- -----
1.904
- --- -_- - --
4.287
1.903
15.07
5.103
360.27
----- ----- ----- -----
1.858
----- ----- -----
4.286
1.858
15.10
5.065
360.27
----- ----- ---- -----
1.813
----- ----- -----
4.285
1.813
15.13
5.026
360.26
----- ----- ---- -----
1.769
----- ----- -----
4.285
1.769
15.17
4.988
360.26
----- ----- ----- -----
1.725
----- ----- -----
4.284
1.724
15.20
4.950
360.26
-- ---- ----- -----
1.680
----- ----- -----
4.283
1.680
15.23
4.911
360.25
----- ----- ---- ---
1.636
----- -- -----
4.283
1.636
15.27
4.873
360.25
----- ----- ---- -----
1.593
----- ----- -----
4.282
1.593
15.30
4.834
360.25
----- ----- ---- -----
1.550
----- ----- -----
4.281
1.550
15.33
4.796
360.25
---- ----- --- -----
1.507
----- ----- ----
4.281
1.507
15.37
4.757
360.24
----- ----- ----- -----
1.464
----- ----- -----
4.280
1.464
15.40
4.719
360.24
----- ----- ----- -----
1.421
----- ----- -----
4.279
1.421
15.43
4.680
360.24
----- ----- ----- -----
1.379
----- ----- -----
4.279
1.379
15.47
4.641
360.23
---- ----- ----- -----
1.337
----- ----- -----
4.278
1.337
15.50
4.603
360.23
----- ----- ----- -----
1.295
----- ----- -----
4.277
1.295
15.53
4.564
360.23
----- ----- ----- -----
1.253
----- ----- -----
4.277
1.253
15.57
4.525
360.23
----- ----- ----- -----
1.211
----- --- -----
4.276
1.211
15.60
4.487
360.22
----- ----- ----- -----
1.170
-- ----- -----
4.275
1.169
15.63
4.448
360.22
----- ----- ----- -----
1.128
----- -- -----
4.275
1.128
15.67
4.409
360.22
----- ----- ----- -- -
1.087
----- ----- -----
4.274
1.087
15.70
4.370
360.21
----- ----- ----- -----
1.046
----- ---- ----
4.273
1.046
15.73
4.331
360.21
---- ----- ----- -----
1.004
----- ----- -----
4.273
1.005
15.77
4.292
360.21
----- ----- -- ----
0.964
-- -- ---
4.272
0.964
15.80
4.253
360.21.
----- ----- ----- -----
0.923
----- ----- -----
4.271
0.923
15.83
4.214
360.20
----- ----- --- -----
0.882
----- ---- -----
4.271
0.882
15.87
4.175
360.20
----- ----- ----- -----
0.842
----- ----- -----
4.270
0.842
15.90
4.136
360.20
----- ----- ----- -----
0.810
----- -- -----
4.269
0.811
15.93
4.097
360.20
----- ----- - - -----
0.788
----- ----- - --
4.269
0.788
15.97
4.058
360.19
----- ----- ----- -----
0.765
----- ----- -----
4.268
0.765
16.00
4.019
360.19
----- ----- ----- -----
0.742
----- ----- -----
4.267
0.742
16.03
3.982
360.19
----- ----- ----- -----
0.718
----- ----- -----
4.267
0.718
16.07
3.953
360.18
----- ----- ----- -----
0.695
----- ---- -----
4.266
0.694
16.10
3.933
360.18
----- ----- ----- -----
0.671
----- ----- -----
4.265
0.671
16.13
3.918
360.18
----- ----- ----- -----
0.647
----- ----- -----
4.265
0.647
16.17
3.904
360.18
----- -w-- ----- -----
0.624
----- ----- -----
4.264
0.624
16.20
3.891
360.17
-- ----- ----- -----
0.600
----- ----- -----
4.263
0.600
16.23
3.877
360.17
----- ---- --- ----
0.578
----- --- ---
4.263
0.578
16.27
3.864
360.17
----- ----- ----- -----
0.555
----- -_--- -----
4.262
0.555
16.30
3.850
360.16
----- ---- -- -- -----
0.532
----- ----- -----
4.261
0.532
...End

7/13/2021 ECMDS 7.0
NORTH
AMERICAN
GREEN
SPILLWAY ANALYSIS
> > > Grass Spillway#1
Name
Grass Spillway#1
Discharge
51.59
Peak Flow Period
4.4
Channel Slope
0.3333
Channel Bottom Width
10
Low Flow Liner
North American Green
5401 St. Wend el -Cynthia na Rd.
Poseyville, Indiana 47633
Tel. [phone]
> Fax [phone]
www.nagreen.com
ECMDS v7.0
Retardence Class
C 6-12 in
Vegetation Type
Mix (Sod and Bunch)
Vegetation Density
Very Good 80-95%
Soil Type
Sandy Loam (GM)
Shoremax - Class
C - Mix (Sod & Bunch) - Very
Good 80-95%
Normal
Permissible
Calculated
Safety
Staple
Phase
Reach
Discharge
Velocity
Mannings N
Remarks
Depth
Shear Stress
Shear Stress
Factor
Pattern
Shoremax w/
Straight 51.59 ds
15.92 ft/s
0.32 ft
0.024
8.5 Ibs/ft2
6.74 Ibs/ft2
1.26
STABLE
G
P550
Unvegetated
Underlying
Straight 51.59 ds
15.92 ft/s
0.32 ft
0.024
8.05 Ibs/ft2
6.33 Ibs/ft2
1.27
STABLE
G
Substrate
-Shoremax w/
Straight 51.59 ds
16.58 ft/s
0.31 ft
0.023
14 Ibs/ft2
6.45 Ibs/ft2
2.17
STABLE
G
P550 Reinforced
Vegetation
Underlying
Straight 51.59 ds
16.58 ft/s
0.31 ft
0.023
8.5 Ibs/ft2
6.07 Ibs/ft2
1.4
STABLE
G
Substrate
https://ecmds.com/projecVl 39235/spillway-analysis/206874/show 1/1

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Pond Report
5
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc v6.066
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas. Average end area method used for volume calculation. Begining Elevation = 357.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft) Contour area (sqft) Incr. Storage (cult) Total storage (cuft)
Tuesday, Jul 13, 2021
0.00
357.00
34,050
0
0
1.00
358.00
36,150
35,100
35,100
2.00
359.00
38,320
37,235
72,335
3.00
360.00
40,535
39,428
111,763
4.00
361.00
42,810
41,673
153,435
5.00
362.00
45,145
43,978
197,413
Culvert / Orifice
Structures
Weir Structures
[A]
[B].
[C]
[PrfRsr]
[A] [B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 10.00 0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 360.10 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)
= 4.500 (by Contour)
Multistage
= 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 7.00
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
Elev (ft)
362.00
361.00
360.00
359.00
358.00
357.00
14.00 21.00 28.00 35.00 42.00 49.00 56.00 63.00 70.00 77.00
Discharge (cfs)

Hydrograph Summary Re p -I-fydraflow Hydrographs Extension for AutoCADO Civil 3DO 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
3.237
2
740
28,885
---
-
SCM Pre -Developed
2
SCS Runoff
33.94
2
718
69,233
------
— -
SCM Post -Developed
3
Reservoir
0.000
2
748
0
2
357.75
26,239
Post Through SCM
5
SCS Runoff
0.136
2
360
656
------
-
—
1.0 Post -Developed to SCM
6
Reservoir
0.000
2
322
0
5
357.01
484
Tuesday, Jul
1.OinPost Through SCM
Infiltration_1.gpw
Return Period:
1 Year
13, 2021

Hydrograph Report
K
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.06 in
Storm duration =
24 hrs
Q (cfs)
4.00
M I1
2.00
1.00
0.00
0 120 240
- Hyd No. 1
SCM Pre -Developed
Hyd. No. 1 -- 1 Year
360 480 600 720 840
Tuesday, Jul 13, 2021
Peak discharge = 3.237 cfs
Time to peak
= 740 min
Hyd. volume
= 28,885 cuft
Curve number
= 58.4
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 30.60 min
Distribution
= Type Il
Shape factor
= 484
Q (Cfs)
4.00
2.00
1.00
0.00
960 1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
91
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.06 in
Storm duration =
24 hrs
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
w
SCM Post -Developed
Hyd. No. 2 -- 1 Year
Tuesday, Jul 13, 2021
Peak discharge = 33.94 cfs
Time to peak
= 718 min
Hyd. volume
= 69,233 cuft
Curve number
= 70.9
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
If 1
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 2

Hydrograph Report
4
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type = Reservoir
Storm frequency = 1 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - SCM Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
35.00
30.00
25.00
15.00
10.00
5.00
Post Through SCM
Hyd. No. 3 -- 1 Year
240 480 720
Hyd No. 3 -- Hyd No. 2
Tuesday, Jul 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 748 min
Hyd. volume
= 0 cuft
Max. Elevation
= 357.75 ft
Max. Storage
= 26,239 cuft
Q (cfs)
35.00
25.00
20.00
15.00
10.00
5.00
0.00
960 1200 1440 1680 1920
® Total storage used = 26,239 cult Time (min)

Hydrograph Report
0
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 5
1.0 Post -Developed to SCM
Hydrograph type
= SCS Runoff
Storm frequency
= 1 yrs
Time interval
= 2 min
Drainage area
= 25.740 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 1.00 in
Storm duration
= 6.00 hrs
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
0
Tuesday, Jul 13, 2021
Peak discharge = 0.136 cfs
Time to peak
= 360 min
Hyd. volume
= 656 cuft
Curve number
70.9
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= SCS 6-Hr
Shape factor
= 484
1.0 Post -Developed to SCM
Hyd. No. 5 -- 1 Year
60 120 180 240 300 360
Hyd No. 5
Q (cfs)
0.50
0.45
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0.00
420
Time (min)

N
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD@ Civil 3D® 2009 byAutodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Hyd. No. 6
1.0inPost Through SCM
Hydrograph type =
Reservoir
Peak di
;charge
= 0.000 cfs
Storm frequency =
1 yrs
Time to
peak
= 322 min
Time interval =
2 min
Hyd. vo
ume
= 0 cuft
Inflow hyd. No. =
5 - 1.0 Post -Developed to SCM
Max. El
vation
= 357.01 ft
Reservoir name =
BMP Pond
Max. St
rage
= 484 cuft
Storage Indication method used.
EAltration extracted from Outflow.
1.0inPost Through SCM
Q (cfs)
Hyd. No. 6 -- 1 Year
Q (c
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
1011h
0 00
0 120 240 360
Hyd No. 6 Hyd No. 5
fs)
480 600 720 840 960
Time (min)
® Total storage used = 484 cult

H yd ro g ra p h Summary Rep-Ffydraflow Hydrographs Extension for AutoCAD® Civil 3D®2009 by Autodesk, Inc. v6.066

Hydrograph Report
10
Hydraflow Hydrographs Extension for AutoCADO Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.70 in
Storm duration
24 hrs
.W
4.00
2.00
SCM Pre -Developed
Hyd. No. 1 -- 2 Year
120 240 360 480 600 720 840
Hyd No. 1
Tuesday, Jul 13, 2021
Peak discharge = 7.967 cfs
Time to peak
= 736 min
Hyd. volume
= 52,095 cuft
Curve number
= 58.4
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 30.60 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
8.00
N. 11
4.00
2.00
0.00
960 1080 1200 1320 1440 1560
Time (min)

Hydrograph Report
11
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D@) 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type
= SCS Runoff
Storm frequency
= 2 yrs
Time interval
= 2 min
Drainage area
= 25.740 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 3.70 in
Storm duration
= 24 hrs
Q (cfs)
60.00
50.00
40.00
30.00
20.00
10.00
SCM Post -Developed
Hyd. No. 2 -- 2 Year
Tuesday, Jul 13, 2021
Peak discharge = 51.83 cfs
Time to peak
= 718 min
Hyd. volume
= 103,976 cuft
Curve number
= 70.9
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
60.00
50.00
40.00
20.00
10.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 2

Hydrograph Report
12
Hydraf low Hydrographs Extension forAutoCAD® Civil 3DO2009 byAutodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - SCM Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
50.00
40.00
30.00
20.00
10.00
0.00
0 240 480
Hyd No. 3
Post Through SCM
Hyd. No. 3 -- 2 Year
720 960
Hyd No. 2
Tuesday, Jul 13, 2021
Peak discharge = 0.000 cfs
Time to peak
- 1064 min
Hyd. volume
= 0 cuft
Max. Elevation
= 358.22 ft
Max. Storage
= 43,414 cuft
Q (cfs)
60.00
50.00
40.00
30.00
20.00
10.00
0.00
1200 1440 1680 1920 2160
Time (min)
® Total storage used = 43,414 cult

15
Hydrograph S u m rn a ry Rep dFy aflow Hydrographs Extension for AutoCAD® 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)
28.20 2
(min)
734
(cuft)
138,058 -
(ft)
(cuft)
1
SCS Runoff
------
SCM Pre -Developed
2
SCS Runoff
107.12 2
718
215,612 -- -
------
--
SCM Post -Developed
3
Reservoir
0.000 2
1444
0 2
360.07
114,577
Post Through SCM
5 SCS Runoff 0.000 I 2 n/a 0
6 Reservoir 0.000 2 n/a ` 0
1.0 Post -Developed to SCM
5 357.00 0.000 1.0inPost Through SCM
Infiltration_1.gpw I Return Period: 10 Year I Tuesday, Jul 13, 2021

Hydrograph Report
16
Hydraflow Hydrographs Extension for AutoCADO Civil 3D@ 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.46 in
Storm duration =
24 hrs
Q (cfs)
30.00
25.00
20.00
15.00
10.00
5.00
I of
I
SCM Pre -Developed
Hyd. No. 1 -- 10 Year
Tuesday, Jul 13, 2021
Peak discharge = 28.20 cfs
Time to peak
= 734 min
Hyd. volume
= 138,058 cuft
Curve number
= 58.4
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 30.60 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
30.00
25.00
20.00
15.00
10.00
5.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 1

Hydrograph Report
17
Hydraf low Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.46 in
Storm duration =
24 hrs
Q (cfs)
120.00
100.00
40.00
20.00
SCM Post -Developed
Hyd. No. 2 -- 10 Year
Tuesday, Jul 13, 2021
Peak discharge = 107.12 cfs
Time to peak
= 718 min
Hyd. volume
= 215,612 cuft
Curve number
= 70.9
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
120.00
100.00
40.00
20.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 2

Hydrograph Report
18
Hydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type = Reservoir
Storm frequency = 10 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - SCM Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
100.00
.M
40.00
20.00
Tuesday, Jul 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 1444 min
Hyd. volume
= 0 cuft
Max. Elevation
= 360.07 ft
Max. Storage
= 114,577 cuft
Post Through SCM
Hyd. No. 3 -- 10 Year
240 480 720 960 1200 1440 1680 1920
Hyd No. 3 Hyd No. 2 ® Total storage used = 114,577 cuft
Q (cfs)
120.00
100.00
40.00
20.00
0.00
2160
Time (min)

21
Hydrograph Summary Rep �-fydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. Hydrograph
No. type
(origin)
Peak
now
(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
71.93
2
734
319,458
—
- —
--
SCM Pre -Developed
2
SCS Runoff
207.83
2
716
423,008
- -
--
SCM Post -Developed
3
Reservoir
51.59
2
724
149,897
2
361.68
183,281
Post Through SCM
5
SCS Runoff
0.000
2
n/a
0
----
------
------
1.0 Post -Developed to SCM
6
Reservoir
0.000
2
n/a
0
Return Period:
5
357.00
Year
0.000
1.0inPost Through SCM
Infiltration_1.gpw
100
Tuesday, Jul
13, 2021

22
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3D® 2009 byAutodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type = SCS Runoff
Storm frequency = 100 yrs
Time interval
= 2 min
Drainage area
= 25.740 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 8.30 in
Storm duration
= 24 hrs
70.00
50.00
40.00
20.00
10.00
w
SCM Pre -Developed
Hyd. No. 1 -- 100 Year
Tuesday, Jul 13, 2021
Peak discharge = 71.93 cfs
Time to peak
= 734 min
Hyd. volume
= 319,458 cuft
Curve number
= 58.4
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 30.60 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
80.00
70.00
50.00
40.00
30.00
20.00
10.00
0.00
120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560
Time (min)
Hyd No. 1

Hydrograph Report
23
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
100 yrs
Time interval =
2 min
Drainage area =
25.740 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
8.30 in
Storm duration =
24 hrs
180.00
150.00
120.00
30.00
SCM Post -Developed
Hyd. No. 2 -- 100 Year
120 240 360 480 600 720 840
Hyd No. 2
Tuesday, Jul 13, 2021
Peak discharge = 207.83 cfs
Time to peak
= 716 min
Hyd. volume
= 423,008 cuft
Curve number
= 70.9
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
210.00
180.00
150.00
120.00
1.1118111
30.00
0.00
960 1080 1200 1320 1440
Time (min)

Hydrograph Report
24
Hydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type =
Reservoir
Storm frequency =
100 yrs
Time interval =
2 min
Inflow hyd. No. =
2 - SCM Post -Developed
Reservoir name =
BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
180.00
150.00
120.00
30.00
I to
1
Tuesday, Jul 13, 2021
Peak discharge = 51.59 cfs
Time to peak
_ 724 min
Hyd. volume
= 149,897 cuft
Max. Elevation
361.68 ft
Max. Storage
= 183,281 cuft
Post Through SCM
Hyd. No. 3 -- 100 Year
Q (cfs)
210.00
180.00
150.00
120.00
30.00
0.00
120 240 360 480 600 720 840 960 1080
Time (min)
Hyd No. 3 Hyd No. 2 ® Total storage used = 183,281 cult

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WATER QUANTITY -INFILTRATION BASIN#2

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SUPPLEMENT-EZ COVER PAGE
LOAD SUPPLEMENT F08105
PROJECT INFORMATION
1
1 Project Name
Walters Meadow
2
Project Area ac
44.756
3
Coastal Wetland Area (ac)
-
4
Surface Water Area ac
5
Is this project High or Low Density?
Hi h
6
Does this project use an off -site SCM?
No
COMPLIANCE WITH 02H .1003(4
7
Width of vegetated setbacks provided (feet)
N/A
8
Will the vegetated setback remain vegetated?
N/A
9
If BUA is proposed in the setback does it meet NCAC 02H.1003 4 c-d ?
_
No
10
Is streambank stabilization proposed on this project?
No
NUMBER AND TYPE OF SCMs:
11
Infiltration System _
Bioretention Cell
2
12
13
_ 0 _
Wet Pond _
Stormwater Wetland
0
0
14
15
Permeable Pavement
0
16
Sand Filter
0
17
Rainwater Harvesting RWH
0
18
Green Roof
0
19
Level Spreader -Filter Strip LS-FS
0
20
Disconnected Impervious Surface (DIS)
0
21
Treatment Swale
0
22
Dry Pond
0
23
StormFilter
0
24
Silva Cell
0
25
Bayfilter
0
26
Filterra
0
LOAD SUPPLEMENT FORMS
DESIGNER CERTIFICATION
27
28
Name and Title.
Or anization.
29
Street address:
Cit ,State, Zip:
30
31
Phone number(s):
32 lEmail
_ Carlo Pardo, PE
Triangle Site Design, PLLC
4004 Barrett Drive, Suite 101
Raleigh, NC 27609
919-553-6570
cnardo0trianalesitedesion.com
Certification Statement:
I certify, under penalty of law that this Supplement EZ form and all supporting information were prepared under my direction or supervision; that the
information provided in the form is, to the best of my knowledge and belief, true, accurate, and complete; and that the engineering plans,
specifications, operation and maintenance agreements and other supporting information are consistent with the information provided here.
',���ttffriiirl1111�'I
�.�� t tr1 C A Rp�
`
SEAL
051571
Signature of Designer
-T
Date

DRAINAGE AREAS
1
1 Is this a high density project?
Yes
2
If so, number of drainage areas/SCMs
2
3
Does this project have low density areas?
No
4
If so, number of low density drainage areas
0
5
Is all/part of this project subject to previous rule
versions?
No
fGRWS LOADED
DRAINAGE AREA INFORMATION
Entire Site
1
4
Type of SCM
Infiltration Basin
Infiltration Basin
5
Total drainage area (sg ft
1453395 sf
1121013
332382
6
Onsite drainage area (sq ft
1438766 sf
1106384
332382
7
Offsite drainage area (sq ft
14629 sf
14629
8
Total BUA in project (sq ft
412787 sf
320712 sf
92075 sf
9
New BUA on subdivided lots (subject to permitting)
(sq ft
10permitting)
New BUA not on subdivided lots (subject to
s
11
Offsite BUA (sq ft
14629 sf
14629 sf
12
Breakdown of new BUA not on subdivided lots:
- Parking (§q ft
- Sidewalk (sq ft
19248 sf
15593 sf
3655 sf
- Roof (sq ft
268000 sf
200000 sf
68000 sf
- Roadway (sq ft)
110910 sf
90490 sf
20420 sf
- Future (sq ft
- Other, please specify in the comment box
below (sq ft
13
New infiltrating permeable pavement on
subdivided lots (sq ft
14
New infiltrating permeable pavement not on
subdivided lots (sq ft
15permitting)
Existing BUA that will remain (not subject to
s ft
16
Existing BUA that is already permitted (sq ft
17
Existing BUA that will be removed (sq ft
18
Percent BUA
29%
28%
19
Design storm inches
1.0 in
1.0 in
20
Design volume of SCM cu ft
28730 cf
8291 cf
21
Calculation method for desi 2n volume
Simple Method
Simple Method
A051M'FW_
L INFORMATION -'
Please use this space to provide any additional information about the
22 drainage area(s):
Infiltration Basin #1 - there is offsite drainage area that is being accounted for
at its full build -out potential (100% BUA)

INFILTRATION SYSTEM
1 Drainage area number 1 2
2 Minimum required treatment volume (cu ft) 28730 cf 829-
3
Is the SCM sized to treat the SW from all surfaces at build -out?
Yes
Yes
4
Is the SCM located away from contaminated soils?
Yes
Yes
5
What are the side slopes of the SCM (H:V or enter "Vertical' for
trenches)?
3:1
3:1
6
Does the SCM have retaining walls, gabion walls or other engineered
side slopes?
No
No
7
Are the inlets, outlets, and receiving stream protected from erosion
10- ear storm)?
Yes
Yes
8
Is there an overflow or bypass for inflow volume in excess of the
clesicin volume?
Yes
Yes
9
What is the method for dewatering the SCM for maintenance?
Pump (preferred)
Pump (preferred)
10
If applicable, will the SCM be cleaned out after construction?
Yes
Yes
11
Does the maintenance access comply with General MDC (8)?
Yes
Yes
12
Does the drainage easement comply with General MDC 9 ?
Yes
Yes
If the SCM is on a single family lot, does (will?) the plat comply with
13
General MDC 10 ?
N/A
N/A
14
Is there an O&M Agreement that complies with General MDC (11)?
Yes
Yes
15
Is there an O&M Plan that complies with General MDC (12)?
Yes
Yes
16
Does the SCM follow the devicespecific MDC?
Yes
Yes
17
Was the SCM desioned by an NC licensed professional?
Yes
Yes
18 Proposed slope of the subgrade surface (%) 0% 0%
19 Are terraces or bafflesprovided? d- No No
20 IType of pretreatment: I Forebay Forebay
Snits Data
21
Was the soil investigated in the footprint and at the elevation of the
infiltrations stem?
Yes
Yes
22
SHWT elevation fmsl
355.00
358.00
23
Depth to SHWT per soils report (in)
60.00
24.00
24 1
Ground elevation at boring in soils report (fmsl)
360.00
360.00
25
Is a detailed hydrogeologic study attached if the separation is
between 1 and 2 feet?
Yes
Yes
26
Soil infiltration rate in/hr
4.50
3.00
27
Factor of safety (FS) (2 is recommended):
2.00
2.00
I Elevations
I Fnr Tranchac t7nly
34
Length (ft)
35
Width ft
36
Perforated pipe diameter, if applicable (inches)
37
Number of laterals
38
Total length of perforated piping
39
Stone type, if applicable
40
Stone porosity (%�_
41
Is stone free of fines?
42
Is the stone wrapped in geotextile fabric?
43
Has at least one inspection port been provided?
vururrrr,�✓wawuvwrr
44 Design volume of SCM (cu ft) 28730 cf 8291 cf
45 1 Time to draw down (hours) 72 hrs 72 hrs
46 Please use this space to provide any additional information about the
infiltration system(s):
Infiltration 1 4:44 PM 7/13/2021

Triangle Site Design, PLLC
Hoke, NC
Curve Number Calculation (CN)
Pre -Developed Conditions
Drainage Area (acres) 7.63
Existino Sail Groups.'
Soil Group Map Symbol Soil Description Acres Percent of DA
A AuA Autryville loamy sand 7.63 100%
Existina Land Uses:
Land Use Description Existing Soil G►oAcres Curve # We�ahled CN
Open - Good Condition A 6.75 60 53.1
Wooded - Good Stand A 0.88 54 6.2
Cumulative Curve # = 59.3

Triangle Site Design, PLLC
Curve Number Calculation
(CN)
Post -Developed Conditions
Drainaoe Area (acres): 7.63
Existing Soil Groups:
Soil Group Map Svmbol Soil Description
Acres
Percent of DA
A AuA Autryville Loamy
Sand
7.63
100%
Proposed Land Uses:
Land Use Description Existing Soil Group
Acres
Curve #
Weighted CN
Impervious Area A
2.12
98
27.2
Open Space - Good Condition A
5.51
60
43.3
Cumulative
Curve # =
70.6

Infiltration Basin Design
Site Information
Sub Area Location:
Drainage To Infiltration Basin #2
Drainage Area (DA) =
7.63 Acres 332382 sf
Impervious Area (IA) =
2.12 Acres 92075 sf
Percent Impervious =
27.70 %
Required Water Quality Volume
Design Storm =
t inch
Determine Rv Value =
0.05 + .009 (1) = 0.30 in/in
Water Quality Volume =
0.190 ac-ft
Water Quality Volume =
8,291 cf
Water Quality Volume =
0.299 inches of runoff
NOAA 1 ear, 24-hour event = 3.06 inches
Minimum Surface Area
SA =
(12-FS-DV)/(K"T)
Factor of Safety (FS) =
2
Design Volume (DV) =
8290.6 cf
Hydraulic Conductivity of Soil =
3.00 in/hr
Max Dewatering Time =
72 hours
SA =
921.2 sf

f STAGE/STORAGE TABLE
INFILTRATION BASIN
STAGE
ELEVATION
CONTOUR
INCREMENTAL
TOTAL
(FT)
(FT)
_ AREA (SF)
STORAGE (CF)
STORA GE (CF)
0.0
360.0
11385
0
0
1.0
361.0
12740
12063
12063
2.0
362.0
14155
13448
25510
3.0
363.0
15620
14888
40398
4.0
364.0
17145
16383
56780
STORMWATER MANAGEMENT DESIGN
INFILTRATION BASIN
RIVER BASIN:
RECEIVING STREAM:
STREAM INDEX:
STREAM CLASS:
HUC:
LUMBER
BUFFALO CREEK
14-2.5
C
03040203
POND DESIGN SUMMARY
DRAINAGE AREA TO POND:
7.63 ACRES
SITE IMPERVIOUS AREA TO POND: 2.12 ACRES
OFF -SITE DESIGN IMPERVIOUS AREA TO POND: 0.00 ACRES
TOTAL DESIGN IMPERVIOUS AREA TO POND: 2.12 ACRES
PRE -DEVELOPED POST -DEVELOPED
DRAINAGE AREA: 7.63 AC 7.63 AC
CURVE NUMBER: 59.3 70.6
INFILTRATION RATE: 3.0 IN/HR
1.0" STORM EVENT:
0.037
CFS
1-YEAR STORM EVENT:
1.594
CFS
9.858
CFS
2-YEAR STORM EVENT:
3.769
CFS
15.12
CFS
10-YEAR STORM EVENT:
12.45
CFS
31.44
CFS
100-YEAR STORM EVENT:
30.27
CFS
61.19
CFS
POST DEVELOPED
THROUGH POND
0.000 CFS
0.000 CFS
0.000 CFS
0.000 CFS
24.90 CFS

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7
Hydrograph Report
Hydraf low Hydrographs Extension for AutoCADO Civil 3DO2009 byAutodesk, Inc. v6.066 Tuesday, Jul 13, 2021
Hyd. No. 3
Post Through SCM
Hydrograph type
= Reservoir
Peak discharge
= 24.90 cfs
Storm frequency
= 100 yrs
Time to peak
= 12.03 hrs
Time interval
= 2 min
Hyd. volume
= 47,141 cuft
Inflow hyd. No.
= 2 - SCM Post -Developed
Reservoir name
= BMP Pond
Max. Elevation
= 363.69 ft
Max. Storage
= 51,391 cuft
Storage Indication method used. Exfiltration extracted from Outflow.
Hydrograph Discharge Table
( Printed values - 1.00% of Op.)
Time
Inflow
Elevation
Clv A Clv B Clv C PfRsr
Wr A
Wr B Wr C Wr D
Exfil
Outflow
(hrs)
cfs
ft
cfs cfs cfs cfs
cfs
cfs cfs cfs
cfs
cfs
11.93
61.19 <<
362.90
-- ----- ----- -----
2.272
----- --- -----
1.074
2.272
11;97
60.25
363.29
- _- -- ----- -----
11.82
----- - - ------
1.116
11.82
12.00
47.92
363.56
----- -- -- ----- --
20.75
----- -- -- -----
1.144
20.75
12.03
30.46
363.67 <<
24.90
----- -- -----
1.156
24.90 <<
12.07
16.89
363.66
----- -- - ----- -----
24.32
----- ----- -----
1.154
24.32
12.10
10.54
363.58
----- -- - ----- -----
21.48
----- ---- -----
1.146
21.48
12.13
8.675
363.50
----- -- - -- -- -----
18.46
----- ----- -----
1.137
18.46
12.17
8.323
363.42
---- - _- ---•- -----
16.02
----- ---- -----
1.130
16.02
12.20
7.988
363.36
----- ----- ----- -----
14.11
----- ----- -----
1.123
14.11
12.23
7.650
363.32
----- -----
12.58
----- ----- -----
1.118
12.58
12.27
7.309
363.27
---- ----- ----- -----
11.36
----- --- -----
1.114
11.36
12.30
6.965
363.24
----- ---- ----- -----
10.33
----- ----- -----
1.110
10.33
12.33
6.619
363.21
----- ----- ----- -----
9.444
----- ----- -----
1.107
9.444
12.37
6.270
363.18
---- --+- ----- -----
8.704
----- ----- -----
1,104
8.704
12.40
5.918
363.16
--__ ..w. ____ -----
8.055
----- ----- -----
1.101
8.055
12.43
5.565
363.13
---- ----- ----- ----
7.458
--- ----- -----
1.099
7.458
12.47
5.209
363.11
-- -- _---- -----
6.905
----- ----- -----
1.097
6.904
12.50
4.852
363.09
----- ----- ----- -----
6.406
----- - -- -----
1.095
6.406
12.53
4.521
363.07
----- ----- ----- -----
5.968
----- - -----
1.093
5.968
12.57
4.274
363.06
-- - -- - ----- -----
5.554
----- ----- -----
1.091
5.554
12.60
4.120
363.04
----- - -- - -
5.172
----- ----- -----
1.089
5.173
12.63
4.022
363.02---
--_-- --- - -----
4.832
- ----- -----
1.087
4.832
12.67
3.943
363.01
----- ----- ----- -----
4.530
----- ----- ----
1.086
4.530
12.70
3.864
363.00
----- ----- ----- ---
4.264
----- - - -----
1.085
4.264
12.73
3.784
362.99
----- - -- ----- --
4.043
----- ----- -----
1.084
4.043
12.77
3.703
362.98
----- ----- ----- ----
3.841
----- ----- -----
1.082
3.842
12.80
3.623
362.97
----- _- - ----- ---
3.658
----- ----- -----
1.082
3.658
12.83
3.542
362.96
----- ----- ----- -- -
3.490
----- - -----
1.081
3.490
12.87
3.461
362.95
----- ----- ----- -_--
3.334
----- ----- -----
1.080
3.335
12.90
3.380
362.94
----- ----- ----- ----
3.190
----- ----- --_--
1.079
3.190
12.93
3.299
362.94
----- ----- ----- -----
3.055
----- ----- ----
1.078
3.055
12.97
3.217
362.93
----- ----- ----- -----
2.927
----- ----- -----
1.078
2.928
13.00
3.135
362.92
----- ----- ----- - -
2.807
----- -- ----
1.077
2.807
13.03
3.057
362.92
----- ----- ----- -----
2.692
----- ----- ___.
1.076
2.692
13.07
2.990
362.91
----- - -- ----- -----
2.584
----- ---- -----
1,076
2.584
13.10
2.936
362.91
----- ----- ---I-- -- - -
2.483
----- ----- -----
1.075
2.483
13.13
2.890
362.90
- --- ----- ...... -----
2.389
----- ----- -----
1.075
2.389
13.17
2.846
362.90
----- ----- ----- -----
2.307
----- --- ----
1.074
2.308
13.20
2.802
362.89
- ---- ----- -----
2.244
---- ----- -----
1.074
2.244
13.23
2.759
362.89
----- ----- ---
2.183
----- ----- -----
1.074
2.182
Continues on next page...

0
Post Through SCM
Hydrograph Discharge Table
Time
Inflow
Elevation
Clv A Clv B Clv C PfRsr
Wr A
Wr B Wr C Wr D
Exfil
Outflow
(hrs)
cfs
ft
cfs cfs cfs cfs
cfs
cfs cfs cfs
cfs
cfs
13.27
2.715
362.89
---- -- - --_-
2.123
----- -- ---
1.073
2.123
13.30
2.671
362.88
----- ----- -- -----
2.066
----- ----- -----
1.073
2.066
13.33
2.626
362.88
- -- - ----
2.010
----- - - -----
1.072
2.010
13.37
2.582
362.88
-- ----- -- -----
1.955
-- - ----- -----
1.072
1.955
13.40
2.538
362.87
----- ----- -- -----
1.902
----- ----- - _
1.072
1.902
13.43
2.493
362.87
----- ____ ____ -___-
1.850
----- ----- -----
1.071
1.849
13.47
2.449
362.86
---- - --- -----
1.798
- - -- -----
1.071
1.798
13.50
2.404
362.86
----- ----- ----- -----
1.748
-- ----- -----
1.071
1.747
13.53
2.361
362.86
----- ----- -- -----
1.698
----- - -----
1.070
1.698
13.57
2.321
362.86
_- -_ - -- -
1.649
----- -- _ --
1.070
1.649
13.60
2.286
362.85
----- ----- - --
1.601
- ----- -----
1.070
1.602
13.63
2.253
362.85
----- ----- -- --
1.556
--- -- -----
1.069
1.556
13.67
2.222
362.85
----- ----- ----- -----
1.511
----- ----- -----
1.069
1.511
13.70
2.190
362.84
----- ----- ----- -----
1.469
----- - -- -
1.069
1.469
13.73
2.158
362.84
----- - --- --
1.427
----- - -----
1.068
1.427
13.77
2.126
362.84
----- --- - -
1.387
----- ----- -----
1.068
1.387
13.80
2.094
362.83
----- ---- - -----
1.347
----- -- -
1.068
1.347
13.83
2.062
362.83
----- - - - - -
1.309
----- ----- --
1.068
1.309
13.87
2.030
362.83
----- --- - -
1.271
----- - - -----
1.067
1.271
13.90
1.997
362.83
----- - - - -- -
1.234
----- ----- -----
1.067
1.234
13.93
1.965
362.83
----- ----- -- --
1.198
----- ----- -----
1.067
1.197
13.97
1.933
362.82
----- -- - -__-- ----
1.161
----- - -- -----
1.067
1.161
14.00
1.901
362.82
----- - -- ---- ---
1.126
----- -- - -----
1.066
1.126
14.03
1.870
362.82
----- ----- ----- ---
1.091
----- ----- -----
1.066
1.091
14.07
1.847
362.82
----- ----- ---- ---
1.057
----- - - -----
1.066
1.057
14.10
1.830
362.81
----- ----- ___ .__.-_
1.024
----- ----- -----
1.066
1.024
14.13
1.818
362.81
---- ----- ----- ---
0.994
----- ---- --
1.066
0.994
14.17
1.807
362.81
----- ----- ---- --
0.965
----- ----- - - -
1.065
0.966
14.20
1.796
362.81
----- ----- ---
0.939
----- ----- --
1.065
0.939
14.23
1.785
362.81
----- ----- ----- --_
0.915
----- ---- -----
1.065
0.915
14.27
1.774
362.80
----- ----- ----- ---
0.892
-- ---- --
1.065
0.892
14.30
1.763
362.80
----- ----- --- --
0.870
----- ---- -----
1.065
0.870
14.33
1.752
362.80
----- ----- ----- -----
0.850
----- - --- -----
1.065
0.850
14.37
1.741
362.80
----- --- - --- -----
0.831
----- _--- - -
1.064
0.831
14.40
1.730
362.80
---- --- - ----- - ---
0.817
----- - -
1.064
0.817
14.43
1.719
362.80
- --
0.807
-= -- -
1.064
0.807
14.47
1.708
362.80
--- - ----- -----
0.797
----- - -- -----
1.064
0.797
14.50
1.697
362.80
----- ----- ----- -----
0.787
----- ----- -----
1.064
0.787
14.53
1.686
362.79
----- ----- ----- -----
0.776
----- ----- --
1.064
0.777
14.57
1.675
362.79
----- ----- ----- ---
0.766
----- ----- -----
1.064
0.766
14.60
1.664
362.79
----- ----- __-- ---
0.756
--- -- -----
1.064
0.756
14.63
1.653
362.79
___.. ----- ----- -----
0.746
----- ----- -
1.063
0.746
14.67
1.641
362.79
----- ----- - -- ---
0.735
----- ----- --
1.063
0.735
14.70
1.630
362.79
----- ----- ----- -----
0.725
---- ----- -----
1.063
0.725
14.73
1.619
362.79
----- ----- ----- -----
0.714
----- ----- -----
1.063
0.714
14.77
1.608
362.79
----- -_ -- ---- -----
0.704
----- ----- -----
1.063
0.704
14.80
1.597
362.78
----- ----- ----- -----
0.693
----- -- - -----
1.063
0.693
14.83
1.586
362.78
----- ----- ----- -----
0.683
----- ----- -----
1.063
0.683
14.87
1.574
362.78
----- ---- --- -----
0.672
----- ----- -----
1.063
0.672
14.90
1.563
362.78
----- ----- ----- -----
0.661
----- ----- -----
1.062
0.661
14.93
1.552
362.78
----- ----- ---
0.651
- ----- -----
1.062
0.651
14.97
1.541
362.78
----- ----- ----- -----
0.640
----- ----- -----
1.062
0.640
15.00
1.530
362.78
----- ----- --- ----
0.629
----- -----
1.062
0.629
Continues on next page -.

0
Post Through SCM
Hydrograph Discharge Table
Time
Inflow
Elevation
Clv A Clv B Clv C PfRsr
Wr A
Wr B Wr C
Wr D Exfil
Outflow
(hrs)
cfs
ft
cfs cfs cfs cfs
cfs
cfs cfs
cfs cfs
cfs
15.03
1.518
362.78
----- ---- -----
0.619
----- -----
----- 1.062
0.619
15.07
1.507
362.77
----- ----- -_-- -----
0.608
--- -----
----- 1.062
0.608
15.10
1.496
362.77
----- -- -----
0.597
----- ---
----- 1.062
0.597
15.13
1.484
362.77
---- ----- ----- -----
0.586
-----
---- 1.061
0.586
15.17
1.473
362.77
----- ----- ----- -----
0.575
----- ----
----- 1.061
0.575
15.20
1.462
362.77
--- ----- ----- -----
0.565
----- -----
----- 1.061
0.565
15.23
1.450
362.77
----- ----- ----- -----
0.554
----- ----
----- 1.061
0.554
15.27
1.439
362.77
----- ----- ----- -----
0.543
----- -----
----- 1.061
0.543
15.30
1.428
362.76
----- ----- ----- -----
0.532
----- -----
----- 1.061
0.532
15.33
1.416
362.76
----- ----- ----- -----
0.521
----- -----
- - - 1.061
0.521
15.37
1.405
362.76
----- ----- ----- -----
0.510
----- -----
1.061
0.510
15.40
1.394
362.76
----- ----- ----- -----
0.499
----- -----
1.060
0.499
15.43
1.382
362.76
----- ----- ----- -----
0.488
----- -----
---- 1.060
0.488
15.47
1.371
362.76
----- ----- ----- -----
0.477
----- -----
1.060
0.477
15.50
1.359
362.76
----- ----- --- -----
0.466
----- -
1.060
0.466
15.53
1.348
362.76
----- ----- ----- -----
0.455
----- -----
----- 1.060
0.455
15.57
1.337
362.75
----- ----- ----- -----
0.444
----- -----
----- 1.060
0.444
15.60
1.325
362.75
----- ----- ----- -----
0.433
----- _----
----- 1.060
0.433
15.63
1.314
362.75
----- ----- ----- -----
0.422
----- - -
----- 1.059
0.422
15.67
1.302
362.75
----- ----- --- ---
0.410
- - -
----- 1.059
0.411
15.70
1.291
362.75
----- ----- - ---
0.399
----- -----
----- 1.059
0.399
15.73
1.279
362.75
----- ----- --- - -----
0.388
----- -----
----- 1.059
0.388
15.77
1.268
362.75
----- ----- ---- -----
0.377
----- -----
----- 1.059
0.377
15.80
1.256
362.74
----- -_--- ----- -----
0.366
----- -----
----- 1.059
0.366
15.83
1.245
362.74
----- ----- ----- -----
0.355
----- -----
----- 1.059
0.355
15.87
1.233
362.74
----- ----- ----- -----
0.344
----- -----
----- 1.058
0.344
15.90
1.222
362.74
----- ----- ----- -----
0.332
--- -
---- 1.058
0.332
15.93
1.210
362.74
----- ----- ----- -----
0.321
----- -----
----- 1.058
0.321
15.97
1.199
362.74
----- ----- ----- -----
0.310
----- -----
---- 1.058
0.310
16.00
1.187
362.74
----- ----- ----- -----
0.299
----- -----
----- 1.058
0.299
16.03
1.176
362.74
----- ----- ----- -----
0.287
----- -----
----- 1.058
0.287
16.07
1.168
362.73
---- ----- ----- -----
0.276
----- ----
----- 1.058
0.276
16.10
1.162
362.73
----- ----- ----- -----
0.266
----- -----
----- 1.057
0.266
16.13
1.157
362.73
---- ----- ----- -
0.255
----- -----
----- 1.057
0.255

7/13/2021
NORTH
AMERICAN
GREEN'
SPILLWAY ANALYSIS
> > > Grass Spillway#2
ECMDS 7.0
Name
Grass Spillway#2
Discharge
24.9
Peak Flow Period'
4.3
Channel Slope
0.3333
Channel Bottom Width
10
Low Flow Liner
Retardence Class
C 6-12 in
Vegetation Type
Mix (Sod and Bunch)
Vegetation Density
Very Good 80-95%
Soil Type
Sandy Loam (GM)
Shoremax - Class C - Mix (Sod & Bunch) - Very Good 80-95%
North American Green
5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
Normal
Permissible
Calculated
Safety
Staple
Phase Reach Discharge Velocity
Mannings N
Remarks
Depth
Shear Stress
Shear Stress
Factor
Pattern
Shoremax w/
Straight
P300
Unvegetated
Underlying
Straight
Substrate
Shoremax w/
Straight
P300 Reinforced
Vegetation
Underlying
Straight
Substrate
24.9 cfs
11.73 ft/s
0.21 ft
0.025
8.5 Ibs/ft2
4.42 Ibs/ft2
1.93
STABLE F
24.9 cfs
11.73 ft/s
0.21 ft
0.025
5.68 Ibs/ft2
4.24 Ibs/ft2
1.34
STABLE F
24.9 cfs
11.5 ft/s
0.22 ft
0.026
14 Ibs/ft2
4.5 Ibs/ft2
3.11
STABLE F
24.9 cfs 11.5 ft/s 0.22 ft 0.026 8.5 Ibs/ft2 4.31 Ibs/ft2 1.97 STABLE F
https:Hecmds.com/project/l 39235/spillway-analysis/206858/show ill

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Pond Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Pond No. 1 - BMP Pond
Pond Data
Contours - User -defined contour areas. Average end area method used for volume calculation. Begining Elevation = 360.00 ft
Stage / Storage Table
Stage (ft) Elevation (ft)
Contour area (sqft)
Incr. Storage (cult)
Total storage (cult)
0.00 360.00
11,385
0
0
1.00 361.00
12,740
12,063
12,063
2.00 362.00
14,155
13,448
25,510
3.00 363.00
15,620
14,888
40,398
4.00 364.00
17,145
16,383
56,780
Culvert / Orifice Structures
Weir Structures
[A]
[B]
[C]
[PrfRsr]
[A]
[B]
[C]
[D]
Rise (in)
Inactive
Inactive
Inactive
Inactive
Crest Len (ft)
= 10.00
0.00
0.00
0.00
Span (in)
= 0.00
0.00
0.00
0.00
Crest El. (ft)
= 362.70
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
Multistage
= 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)
= 3.000 (by
Contour)
Multistage
= n/a
No
Yes
No
TW Elev. (ft)
= 0.00
Stage (ft)
4.00
3.00
2.00
1.00
0.00
0.00 4.00
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
8.00 1200 16.00 20.00 24.00 28.00 32.00
Elev (ft)
364.00
363.00
362.00
361.00
360.00
36.00 40.00
Discharge (cfs)

H yd ro g ra p h Summary Re p raflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hydrograph
description
SCM Pre -Developed
SCM Post -Developed
Post Through SCM
1.0 Post -Developed to SCM
1.0inPost Through SCM
Jul 13, 2021

Hydrograph Report
2
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO2009 byAutodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Peak discharge
= 1.594 cfs
Storm frequency =
1 yrs
Time to peak
= 12.13 hrs
Time interval =
2 min
Hyd. volume
= 9,210 cuft
Drainage area =
7.630 ac
Curve number
= 59.3
Basin Slope =
0.0 %
Hydraulic length
= 0 ft
Tic method =
USER
Time of conc. (Tc)
= 20.10 min
Total precip. =
3.06 in
Distribution
= Type II
Storm duration =
24 hrs
Shape factor
= 484
1.00
0.00
0 2 4
Hyd No. 1
SCM Pre -Developed
Hyd. No. 1 -- 1 Year
6 8 10 12 14 16 18 20 22 24
Q (cfs)
2.00
1.00
0.00
26
Time (hrs)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
1 yrs
Time interval =
2 min
Drainage area =
7.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.06 in
Storm duration =
24 hrs
Q (cfs)
10.00
AM
4.00
2.00
0.00 1
0 2 4
— Hyd No. 2
6 8
SCM Post -Developed
Hyd. No. 2 -- 1 Year
M
Tuesday, Jul 13, 2021
Peak discharge = 9.858 cfs
Time to peak
= 11.97 hrs
Hyd. volume
= 20,151 cuft
Curve number
= 70.6
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
l I I I I I 1 1_ 0.00
10 12 14 16 18 20 22 24 26
Time (hrs)

4
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 3D® 2009 byAutodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Hyd. No. 3
Post Through SCM
Hydrograph type =
Reservoir
Peak discharge
= 0.000 cfs
Storm frequency =
1 yrs
Time to peak
= 15.50 hrs
Time interval =
2 min
Hyd. volume
= 0 cuft
Inflow hyd. No. =
2 - SCM Post -Developed
Max. Elevation
= 360.69 ft
Reservoir name =
BMP Pond
Max. Storage
= 8,342 cuft
Storage Indication method used. ExflItration extracted from Outflow.
Q (cfs)
10.00
M
4.00
2.00
Post Through SCM
Hyd. No. 3 -- 1 Year
4 8 12 16 20 24 28 32
Hyd No. 3 Hyd No. 2 Total storage used = 8,342 cuft
Q (cfs)
10.00
M
4.00
2.00
0.00
36
Time (hrs)

Hydrograph Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 3DO2009 byAutodesk, Inc. v6.066
Hyd. No. 5
1.0 Post -Developed to SCM
Hydrograph type
= SCS Runoff
Storm frequency
= 1 yrs
Time interval
= 2 min
Drainage area
= 7.630 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 1.00 in
Storm duration
= 6.00 hrs
Q (cfs)
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
0.0 1.0
Hyd No. 5
Tuesday, Jul 13, 2021
Peak discharge = 0.037 cfs
Time to peak
= 6.00 hrs
Hyd. volume
= 167 cuft
Curve number
= 70.6
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= SCS 6-Hr
Shape factor
= 484
1.0 Post -Developed to SCM
Hyd. No. 5 -- 1 Year
2.0 3.0 4.0 5.0 6.0
Q (cfs)
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
7.0
Time (hrs)

7
Hydrograph Report
Hydraflow Hydrographs Extension forAutoCADO Civil 3D® 2009 byAutodesk, Inc. v6.066 Tuesday, Jul 13, 2021
Hyd. No. 6
1.0inPost Through SCM
Hydrograph type = Reservoir Peak discharge - 0.000 cfs
Storm frequency = 1 yrs Time to peak = 5.60 hrs
Time interval = 2 min Hyd. volume - 0 cuft
Inflow hyd. No. = 5 - 1.0 Post -Developed to SCM Max. Elevation = 360.01 ft
Reservoir name = BMP Pond Max. Storage - 137 cuft
Storage Indication method used. Exfiltration extracted from Outflow
Q (cfs)
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
0.0
1.01nPost Through SCM
Hyd. No. 6 -- 1 Year
2.0 4.0 6.0 8.0 10.0 12.0
Hyd No. 6 Hyd No. 5 ® Total storage used = 137 cult
Q (cfs)
0.10
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
14.0
Time (hrs)

H yd ro g ra p h Summary Re PC Fiyraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066

Hydrograph Report
Hydraf low Hydrographs Extension forAutoCAD® Civil 31D®2009 byAutodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type -
SCS Runoff
Storm frequency =
2 yrs
Time interval =
2 min
Drainage area =
7.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
3.70 in
Storm duration =
24 hrs
3.00
2.00
1.00
0.00
0 2 4
- Hyd No. 1
SCM Pre -Developed
Hyd. No. 1 -- 2 Year
6 8 10 12 14
i If,
Tuesday, Jul 13, 2021
Peak discharge = 3.769 cfs
Time to peak
= 12.13 hrs
Hyd. volume
= 16,322 cuft
Curve number
= 59.3
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 20.10 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
4.00
3.00
2.00
1.00
0.00
16 18 20 22 24 26
Time (hrs)

11
Hydrograph
Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Tuesday, Jul
13, 2021
Hyd. No. 2
SCM Post -Developed
Hydrograph type
= SCS Runoff
Peak discharge
= 15.12 cfs
Storm frequency
= 2 yrs
Time to peak
= 11.97 hrs
Time interval
= 2 min
Hyd. volume
= 30,357 cuft
Drainage area
= 7.630 ac
Curve number
= 70.6
Basin Slope
= 0.0 %
Hydraulic length
= 0 ft
Tc method
= USER
Time of conc. (Tc) = 5.00 min
Total precip.
= 3.70 in
Distribution
= Type II
Storm duration
= 24 hrs
Shape factor
= 484
SCM Post -Developed
Q (cfs)
Hyd. No. 2 -- 2 Year
Q (cfs)
18.00
18.00
15.00
15.00
12.00
12.00
9.00
9.00
6.00
6.00
3.00
3.00
0.00
0.00
0 2 4 6 8 10 12 14 16
18 20 22
24 26
Time (hrs)
-- Hyd No. 2

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type = Reservoir
Storm frequency = 2 yrs
Time interval = 2 min
Inflow hyd. No. = 2 - SCM Post -Developed
Reservoir name = BMP Pond
Storage Indication method used. Exfiltration extracted from Outflow
15.00
12.00
• 11
. 11
3.00
12
Tuesday, Jul 13, 2021
Peak discharge = 0.000 cfs
Time to peak
= 16.50 hrs
Hyd. volume
= 0 cuft
Max. Elevation
- 361.11 ft
Max. Storage
= 13,499 cuft
Post Through SCM
Hyd. No. 3 -- 2 Year
4 8 12 16 20 24 28 32
Hyd No. 3 Hyd No. 2 FFFFTTTI Total storage used = 13,499 cuft
Q (cfs)
18.00
15.00
12.00
MIX
K 11
0.00
36
Time (hrs)

15
H yd ro g ra p h Summary Re PC Ofy raflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCAD® Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
10 yrs
Time interval =
2 min
Drainage area =
7.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
5.46 in
Storm duration =
24 hrs
Q (cfs)
14.00
12.00
10.00
e
4.00
2.00
0.00
0 2 4
Hyd No. 1
SCM Pre -Developed
Hyd. No. 1 -- 10 Year
6 8 10 12 14
16
Tuesday, Jul 13, 2021
Peak discharge = 12.45 cfs
Time to peak
= 12.10 hrs
Hyd. volume
= 42,254 cuft
Curve number
= 59.3
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 20.10 min
Distribution
= Type II
Shape factor
= 484
Q (cfs)
14.00
12.00
10.00
M
4.00
2.00
0.00
16 18 20 22 24 26
Time (hrs)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type = SCS Runoff
Storm frequency = 10 yrs
Time interval
= 2 min
Drainage area
= 7.630 ac
Basin Slope
= 0.0 %
Tc method
= USER
Total precip.
= 5.46 in
Storm duration
= 24 hrs
30.00
25.00
20.00
15.00
10.00
5.00
0.00
0 2 4
- Hyd No. 2
SCM Post -Developed
Hyd. No. 2 -- 10 Year
6 8 10 12 14
17
Tuesday, Jul 13, 2021
Peak discharge = 31.44 cfs
Time to peak
= 11.97 hrs
Hyd. volume
= 63,236 cuft
Curve number
= 70.6
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
15.00
10.00
5.00
0.00
16 18 20 22 24 26
Time (hrs)

18
Hydrograph
Report
Hydraflow Hydrographs Extension forAutoCAD® Civil 31DO 2009 byAutodesk, Inc. v6.066
Tuesday, Jul 13, 2021
Hyd. No. 3
Post Through SCM
Hydrograph type
= Reservoir
Peak discharge
= 0.000 cfs
Storm frequency
= 10 yrs
Time to peak
= 13.90 hrs
Time interval
= 2 min
Hyd. volume
= 0 cuft
Inflow hyd. No.
= 2 - SCM Post -Developed
Max. Elevation
= 362.66 ft
Reservoir name
= BMP Pond
Max. Storage
= 35,294 cuft
Storage Indication method used. EAltration extracted from Outflow.
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00
0 4
Hyd No. 3
Post Through SCM
Hyd. No. 3 -- 10 Year
8 12 16 20 24 28
Hyd No. 2 Total storage used = 35,294 cuft
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
0.00
32
Time (hrs)

21
H yd ro g ra p h Summary Re p 'Ffydraflow Hydrographs Extension for AutoCADO Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. Hydrograph Peak Time Time to
No. type flow interval peak v
(origin) (cfs) (min) (min)
1
SCS Runoff
30.27
2
724
9
2
SCS Runoff
61.19
2
716
1
3
Reservoir
24.90
2
722
4
5
SCS Runoff
0.000
2
n/a
0
6
Reservoir
0.000
2
n/a
0
Infiltration_2.gpw I F

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 3D® 2009 by Autodesk, Inc. v6.066
Hyd. No. 1
SCM Pre -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
100 yrs
Time interval =
2 min
Drainage area =
7.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
8.30 in
Storm duration =
24 hrs
Q (cfs)
35.00
30.00
25.00
20.00
15.00
10.00
5.00
2 4 6
Hyd No. 1
SCM Pre -Developed
Hyd. No. 1 -- 100 Year
22
Tuesday, Jul 13, 2021
Peak discharge = 30.27 cfs
Time to peak
= 12.07 hrs
Hyd. volume
= 96,377 cuft
Curve number
= 59.3
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 20.10 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
8 10 12 14 16 18 20 22 24 26
Time (hrs)

Hydrograph Report
Hydraflow Hydrographs Extension for AutoCADO Civil 3DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 2
SCM Post -Developed
Hydrograph type =
SCS Runoff
Storm frequency =
100 yrs
Time interval =
2 min
Drainage area =
7.630 ac
Basin Slope =
0.0 %
Tc method =
USER
Total precip. =
8.30 in
Storm duration =
24 hrs
23
Tuesday, Jul 13, 2021
Peak discharge = 61.19 cfs
Time to peak
= 11.93 hrs
Hyd. volume
= 124,474 cuft
Curve number
= 70.6
Hydraulic length
= 0 ft
Time of conc. (Tc)
= 5.00 min
Distribution
= Type II
Shape factor
= 484
SCM Post -Developed
Q (cfs) Hyd. No. 2 -- 100 Year Q (cfs)
70.00
60.00
50.00
40.00
30.00
20.00
10.00
0 00
70.00
60.00
50.00
40.00
30.00
20.00
10.00
0 00
0 2 4 6 8 10 12 14 16 18 20 22 24
Hyd No. 2 Time (hrs)

Hydrograph Report
24
Hydraflow Hydrographs Extension for AutoCAD® Civil 31DO 2009 by Autodesk, Inc. v6.066
Hyd. No. 3
Post Through SCM
Hydrograph type =
Reservoir
Storm frequency =
100 yrs
Time interval =
2 min
Inflow hyd. No. =
2 - SCM Post -Developed
Reservoir name =
BMP Pond
Storage Indication method used. Extiltration extracted from Outflow
50.00
40.00
30.00
20.00
10.00
Tuesday, Jul 13, 2021
Peak discharge = 24.90 cfs
Time to peak
= 12.03 hrs
Hyd. volume
= 47,141 cuft
Max. Elevation
= 363.69 ft
Max. Storage
= 51,391 cuft
Post Through SCM
Hyd. No. 3 -- 100 Year
2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0
Hyd No. 3 Hyd No. 2 ® Total storage used = 51,391 cuft
Q (cfs)
70.00
50.00
40.00
30.00
20.00
10.00
0.00
18.0
Time (hrs)

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