SW3201002_7-Eleven Long Ferry Road SIA - 210118_20210119

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7-ELEVEN LONG FERRY ROAD
Stormwater Impact Analysis and Final Design of Stormwater Management Facility
WADAMS

7-ELEVEN LONG FERRY ROAD
Salisbury, North Carolina
Stormwater Impact Analysis &
Design of Stormwater Control Measures
Project Number:
Designed By:
Date:
Re -Submittal Date:
'J
CPR-20000
Jonathan Woodard, PE
October 2020
January 2020
WADAMS
3430 Toringdon Way, Suite 110
Charlotte, North Carolina 28277
NC Lic. # C-0293
CA
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2 MCADAMS STORMWATER IMPACT ANALYSIS
GENERAL DESCRIPTION
Located in Rowan County at the south-west corner of the intersection of Long Ferry Road and Front Creek
Road, is a proposed 7-Eleven convenience store and fuel station. The existing site consists of grass and
existing impervious area. Proposed development on this site will consist of a 7-Eleven convenience store
and fuel station, along with the associated parking lot, sidewalks, utility improvements, and one
stormwater control measure.
The proposed development is located within the Yadkin River basin with stormwater runoff from the
proposed development draining into Town Creek (Class C — index number 12-115-3). This development is
located within Rowan County and as a result the proposed stormwater management on this site shall
meet the minimum design criteria of NCDEQ:
NCDEQ Design Standards
A. Development Standards For High Density Projects (per 15A NCAC 02H .1003)
(a) SCMs shall be designed, constructed, and maintained so that the project achieves either "runoff
treatments" or "runoff volume match".
(b) When new built -upon area is added to existing development or existing development is replaced
with new built -upon area, only the area of the next increase shall be subject to this Section.
(c) SCMs shall meet the relevant MDC.
1. Storm Water Quality Treatment and Volume Match
Sand filters are designed to treat 0.75 times the design volume (discounted volume).
2. Storm Water Quality Treatment
All structural storm water treatment systems used to meet these requirements shall be designed to have
minimum of 85% average annual removal for Total Suspended Solids.
3. Storm Water Treatment System Design
General engineering design for the proposed sand filter is based on the MDC set forth in the NCDEQ
Stormwater Design Manual.
4. Storm Water Peak Control
Peak control is not required.
To meet the above requirements, one sand filter is proposed to treat the net increase of impervious area
for the proposed development. Please refer to the appropriate section of this report for additional
information.
creating experiences through experience 3430 Toringdon Way, Suite 110, Charlotte, NC 28277 / 704. 527. 0800

TI MCADAMS STORMWATER IMPACT ANALYSIS
CALCULATION METHODOLOGY
> Rainfall data for the analysis was taken from the most current data available from the National
Oceanic and Atmospheric (NOAA) Precipitation Frequency Data Server website.
> Using maps contained within the Rowan County Soil Survey, the on -site soils were determined to
be hydrologic soil group (HSG) 'B'.
> A composite SCS Curve Number was calculated for both the pre- and post -development condition
for each sub -basin using SCS curve numbers and land cover conditions. Land cover conditions for
the pre -development condition were taken from available survey and GIS information. Land cover
conditions for the post -development condition were taken from the proposed development plan.
> The time of concentration was calculated using SCS TR-55 (Segmental Approach, 1986). The Tc
flow path was divided into three segments: overland flow, concentrated flow, and channel flow.
The travel time was then computed for each segment, from which the overall time of
concentration was determine by taking the sum of each segmental time.
PondPack Version V8i was used in determined the post -development peak flow rate for the 100-
year storm event to check for overtopping, as well as routing calculations for the proposed
stormwater control measure.
> The proposed stormwater control measure was designed in accordance with the Minimum
Design Criteria (MDC) standards set forth in the NCDEQ Stormwater Design Manual.
DISCUSSION OF RESULTS
Water Quality Requirements:
The proposed facility has been designed in accordance with the Minimum Design Criteria (MDC)
standards set forth in the NCDEQ Stormwater Design Manual. The proposed facility will provide the
required 85% TSS removal.
CONCLUSION
If the development on this tract is built as proposed within this report, then the requirements set forth in
NCDEQ's Post -Construction Stormwater Ordinance will be met. However, modifications to the proposed
development may require that this analysis be revised. Some modifications that would require this
analysis to be revised include:
> The proposed site impervious surface exceeds the amount accounted for in this report.
> The post -development watershed breaks change significantly from those used to prepare this
report.
The above modifications may result in the assumptions within this report becoming invalid. The
computations within this report will need to be revisited if any of the above conditions become apparent
as development of the proposed site moves forward.
creating experiences through experience 2 of 2

1 SUMMARY OF RESULTS
2 MISCELLANEOUS SITE INFORMATION
3 WATERSHED SOILS INFORMATION
4 SITE PRECIPITATION DATA
5 PRE -DEVELOPMENT HYDROLOGIC CALCULATION
6 POST -DEVELOPMENT HYDROLOGIC
CALCULATIONS
7 STORMWATER CONTROL MEASURE A DESIGN
CALCULATIONS

SUMMARY OF RESULTS
7-ELEVEN LONG FERRY ROAD
CPR-20000

'J MCADAMs
SUMMARY OF RESULTS
Project Name: 7-Eleven - Long Ferry Road
Project Numbei CPR-20000
STORMWATER CONTROL MEASURE A SUMMARY
Design Drainage Area =U61
acres
Design Impervious Area = acres
% Impervious =
Water Quality Volume dis = cf
Top of Dam = 706.50 ft
Riser = 4'x4' (internal dimensions)
Riser Elevation =1 705.00 ft
Invert In =ft
Invert Out =ft
Barrel Diameter =W42
Length =ft
in
Emergency Spillwayl 10 Ift
Invert In = 705.00 ft
STORMWATER CONTROL MEASURE A ROUTING RESULTS
Date: 1/15/2021
Calculated By: J. Woodard, PE
Return Period
Inflow
[cfs]
Outflow
[cfs]
Max WSE
[ft]
Freeboard
[ft]
WQV
4.39
0.16
704.13
2.37
100-Year
25.90
23.96
705.48
1.02

MISCELLANEOUS SITE INFORMATION
7-ELEVEN LONG FERRY ROAD
CPR-20000

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0 1,000 2,000 4,000 PROJECT#: CPR-20000
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Hydrologic Soil Group —Rowan County, North Carolina
PreDev DA
Hydrologic Soil Group
Map unit symbol
Map unit name
Rating
Acres in AOI
Percent of AOI
EnC
Enon fine sandy loam, 8
to 15 percent slopes
C
0.1
2.2%
LdB2
Lloyd clay loam, 2 to 8
percent slopes,
moderately eroded
B
4.8
97.8%
Totals for Area of Interest
4.9
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 Web Soil Survey 9/22/2020
Conservation Service National Cooperative Soil Survey Page 3 of 4

Hydrologic Soil Group —Rowan County, North Carolina
PreDev DA
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.- None Specified
Tie -break Rule: Higher
USDA Natural Resources Web Soil Survey 9/22/2020
Conservation Service National Cooperative Soil Survey Page 4 of 4

PRECIPITATION DATA
7-ELEVEN LONG FERRY ROAD
CPR-20000

'J MCADAMS
RAINFALL CALCULATIONS
Project Name: 7-Eleven Long Ferry Road
Project Number: CPR-20000
INPUT DATA
(REF: NOAA Atlas 14).
Copy input data from NOAA Atlas 14.
Paste Speclal.. Values and Transpose
Date: 1020/2020
Calculatec J. Woodard, PE
ARI 5 10 15 30 60 120 3 6 12 24 48 3 4 7 10 20 30 45 60

PRE -DEVELOPMENT HYDROLOGIC
CALCULATIONS
7-ELEVEN LONG FERRY ROAD
CPR-20000

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TJ MCADAMs
PRE DEVELOPMENT HYDROLOGIC CALCULATIONS
Project Name: 7-Eleven - Long Ferry Road Date: 12/31/2020
Project Numbei CPR-20000 Calculated By: J. Woodard, PE
Subbasin ID: 1
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
HSG 'A = 0%
HSG
B' 100%
HSG'C'= 0%
HSG 'D' =
Cover Composite
Condition SCS CN Comments
impervious
98
Open
61
Assume good condition
0o a
Assume good condition
on
WATERSHED BREAKDOWN
Composite Area Area
Contributing Area SCS CN fsfl facresl Comments
Onsite Impervious
98
11,496
0.26
Onsite Open
61
130,482
3.00
Assume good condition
Onsite Wooded
55
0
0.00
Assume good condition
Onsite Pond
100
0
0.00
Offsite Impervious
98
34,380
0.79
Offsite Open
61
1 35,371
0.81
Assume good condition
Offsite Wooded
55
0
0.00
Assume good condition
Offsite Pond
100
0
0.00
Total Area = 211,729 sf
= 4.86 acres
Composite SCS CN = 69
% Impervious = 21.67%
TIME OF CONCENTRATION
(REF: SCS Segmental Approach, TR-55)
Segment 1: Overland Flow
Length =
Upstream Elevation =
Downstream Elevation =
Height =
Slope =
Manning's n =
P (2-year/24-hour) =
Segment Time =
Segment 2: Concentrated Flow
ft Length =
ft Upstream Elevation =
ft Downstream Elevation =
ft Height =
ft/ft Slope =
short grass prairie Paved?
inches (Salisbury, NC) Velocity =
minutes Segment Time =1
ft
ft
ft
ft
ft/ft
ft/sec
Iminutes
300
277
719.50
714.25
714.25
697.00
5.25
17.25
0.0175
0.0623
0.15
No
3.30
4.03
24.51
1.15
Time of Concentration = 25.66 minutes
SCS Lag Time = 15.39 minutes

POST -DEVELOPMENT HYDROLOGIC
CALCULATIONS
7-ELEVEN LONG FERRY ROAD
CPR-20000

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TIMCADAMS
POST DEVELOPMENT HYDROLOGIC CALCULATIONS
Project Name: 7-Eleven - Long Ferry Road
Project Numbei CPR-20000
Subbasin ID: 1-To SCM A
SCS CURVE NUMBER
(REF: TR-55 and NRCS Web Soil Survey).
HSG Impervious Open Wooded Pond
HSG'A' =
0°k
HSG'B' =
100°k
HSG'C' =
0°k
HSG'D' =
0°k
Cover
Composite
Condition
SCS CN Comments
mpervious
R
-
pen 1
6 1
Assume good condition
Wooded
Assume good condition
on
WATERSHED BREAKDOWN
Date: 1 /5/2021
Calculated By: J. Woodard, PE
Composite Area Area
Contributing Area SCS CN 1sfl [acres] Comments
Onsite Impervious
98
117,034
2.69
Onsite Open
61
18,268
0.42
Assume good condition
Onsite Wooded
55
0
0.00
Assume good condition
Onsite Pond
100
5,335
0.12
Offsite Impervious
98
5,396
0.12
Offsite Open
61
0
0.00
Assume good condition
Offsite Wooded
55
0
0.00
Assume good condition
Offsite Pond
1 100
L 0
0.00
Total Area =
146,033
sf
acres
Composite SCS CN =
93
% Impervious
TIME OF CONCENTRATION
Time of Concentration = 5.00 minutes
SCS Lag Time =j 3.00 Iminutes

DESIGN OF STORMWATER CONTROL
MEASURE A
7-ELEVEN LONG FERRY ROAD
CPR-20000

0 MCADAMS
STAGE -STORAGE FUNCTION - SAND FILTER'A'
Project Name: 7-Eleven - Long Ferry Road Date: 1/15/2021
Project Number: CPR-20000 Calculated By: J. Woodard, PE
Facility ID: SCM A
SAND FILTER
Average Incremental Accumulated Calculated
Contour Stage Contour Area Contour Area Contour Vol Contour Vol Stage LN Storage
rffl rffl rcfl rcfl rcfl rcfl rffl
703.00
0.00
1,826
703.50
0.50
1,888
1,857
929
929
0.50
6.83
704.00
1.00
1 1,951
1 1,920
1 960
1 1,888
0.99
1 7.54
705.00
2.00
1 2,079
1 2,015
1 2,015
1 3,903
2.01
1 8.27
Storage vs. Stage
3500
3000 y = 1329.2x1 2173
2500 R' = 0.9997
2000
1500
N
1000
500
0
0 0.5 1 1.5 2 2.5
Stage (feet)
b = 1.0359
Ks = 1 1899

'J MCADAMS
STAGE -STORAGE FUNCTION - PRE-TREATMENT 'A'
Project Name: 7-Eleven - Long Ferry Road Date: 1/15/2021
Project Number: CPR-20000 Calculated By: J. Woodard, PE
Facility ID: SCM A
PRE-TREATMENT
Average Incremental Accumulated Calculated
Contour Stage Contour Area Contour Area Contour Vol Contour Vol Stage LN Storage
rffl rffl rcfl rcfl rcfl rcfl rffl
703.00
0.00
1,987
703.50
0.50
2,206
2,097
1,048
1,048
0.50
6.95
704.00
1.00
1 2,427
1 2,317
1 1,158
1 2,207
0.99
1 7.70
705.00
2.00
1 2,888
1 2,658
1 2,658
1 4,864
2.01
1 8.49
9000
8000
Storage vs. Stage
7000
y = 2122.2x' e492
R' = 0.9997
6000
5000
4000
3000
2000
1000
0
0 0.5 1 1.5 2 2.5
Stage (feet)
b= 1.1071
Ks = 1 2241

2 MCADAMS
STAGE -STORAGE FUNCTION - TOTAL 'A'
Project Name: 7-Eleven - Long Ferry Road Date: 1/15/2021
Project Number: CPR-20000 Calculated By: J. Woodard, PE
Facility ID: SCM A
TOTAL STORAGE ABOVE SAND FILTER
Average Incremental Accumulated Calculated
Contour Stage Contour Area Contour Area Contour Vol Contour Vol Stage LN Storage LN Stage
rffl rffl rcfl rcfl rcfl rcfl rffl
703.00
0.00
3,813
704.00
1.00
4,378
4,096
4,096
4,096
1.00
8.32
0.00
705.00
2.00
4,967
4,673
4,673
8,768
1.98
9.08
0.69
705.50
2.50
5,305
5,136
2,568
11,336
2.50
9.34
0.92
706.00
3.00
5,491
5,398
2,699
14,035
3.02
9.55
1.10
706.50
3.50
5,779
5,635
2,818
16,853
3.56
9.73
1.25
40000
35000
Storage vs. Stage
y = 3522.6xi 5663
30000
R' = 0.9996
25000
20000
N 15000
10000
5000
0
0 1 2 3 4 5
Stage (feet)
b = 1.1176
Ks = 1 4080

M WADAMS
WATER QUALITY VOLUME CALCULATION
Project Name: 7-Eleven - Long Ferry Road Date: 1/15/2021
Project Number: CPR-20000 Calculated By: J. Woodard, PE
Facility ID: SCM A
DETERMINATION OF WATER QUALITY VOLUME
(REF: Simple Method, Schueler, 1987).
WQV = P x R, x A / 12
where,
WQV = Water Quality Volume (acre-ft)
Rv = 0.05 + 0.009 x I, where I is % Impervious Cover
A = Area (acres)
P = Rainfall (inches)
Total Drainage Area, A
= 3.35
acres
Net Increase in Imp. Area
= 2.60
acres
Impervious, 1
= 77.6%
Rainfall, P=
1.00
inches
Rv
= 0.75
WQV
= 0.21
�cf
acre-ft
9,103
Sizing is based upon the discounted
water ualit volume, WQVdis (75% of the total WQV) per MDC standards
WQVdis=
6827 cf
SAND FILTER SIZING
where,
AF = WQVdis / D
AF = surface area of filter bed (sf)
WQVdis= discounted water quality volume (cf)
D = ponding depth
WQVdis= 1 % 27 cf
D = 2.00 ft
AF = 3,414 sf (minimum sand filter surface area required)
Ap = 3,813 sf (sand filter area provided)
Design Summary

(REF: MDC).
Asf >
Asf >
Asand >
Asand >
Ased >
Ased >
D =
3,414
sf (min. total sand and sedimentation chamber surface area)
sf (total sand and sedimentation chamber surface area provided)
sf (min. sand chamber area required)
sf (min. sand chamber area provided)
sf (min. sedimentation chamber area required)
sf (min. sedimentation chamber area provided)
ft (max. WQVdis ponding depth in facility)
3,813
1,707
1,826
1,707
1,987
2.00
UNDERDRAIN SIZING
(REF: Charlotte -Mecklenburg BMP Design Manual).
Compute drawdown through filter bed
Q = A(k)(hF'dF)/(dF)
where,
A = provided surface area of filter bed (sf)
k= coefficient of permeability of filter media (ft/day)
hF = height of water above filter bed (feet)
dF = filter bed depth (feet)
A= 1,826 sf
k= 3.50 ft/day
hF = 2.00 ft
dF= 1.00 ft
Q-1 19,173 cf/day
= 0.222 cfs
Compute minimum drawdown discharge
WQV = 9,103 cf
t= 1.667 days
Minimum drawdown, Q= 0.063 cfs
Compute underdrain pipe capacity
Number of rows, n =
2
Diameter of underdrains, d =
6
inches
Area, A
= 0.196
sf
Wetted perimeter, P=
1.571
ft
Slope, S =
0.005
ft/ft
Capacity of one pipe =
0.395
cfs
Total capacity =
0.790
cfs
Assume 50% clogging
= 0.395
cfs DESIGN ACCEPTABLE
Compute underdrain preforation capacity
3/8-inch perforations spaced 3 inches on center, along 4 longitudinal rows spaced 90 ° apart
Number of rows, n =
2
Diameter of underdrains, d =
6
inches
Length of underdrains, L =
36
ft
Number of perforations
= 1,152
holes
Capacity of one hole =
0.008
cfs
Total capacity =
9.513
cfs
Assume 50% clogging
= 4.757
cfs DESIGN ACCEPTABLE
STAGE -DISCHARGE FOR SAND MEDIA
(REF: Charlotte -Mecklenburg BMP Design Manual).
AF= [(WQV)(dF)1/1(k)(hA' dF)(t)1
WQV / t = Qo = AF (k)(hF' dF)/(dF)
A= 1,826 sf
dF= 1.00 ft
Surface of sand media = 703.00 ft
k= 3.50 ft/day
Elevation Height hF Discharge Qo
rftl rftl rsfl
703.00
0.00
0.000
703.50
0.50
0.111
704.00
1.00
0.148
704.50
1.50
0.185

'J McADAMS
II'll RIM IM:1►10a31111IIIA0[QL111W:11[K11W.1%0[QL1I
Project Name: 7-Eleven - Long Ferry Road
Project Number: CPR-20000
Facility ID: SCM A
INPUT DATA
Inside Length =
4.00
ft
Inside Width =
4.00
ft
Wall Thickness =
6.00
in
Standard Base Length =
5.00
ft
Standard Base Width =
5.00
ft
Standard Base Thickness =
6.00
in
Inside Height of Riser =
5.95
ft
Concrete Unit Weight =
142.00
pcf
Outside Diameter of Barrel =
30.00
in
Drain Pipe (if present) =
0.00
in
CONCRETE PRESENT IN RISER STRUCTURE
Riser Walls =
53.550
cf
Standard Base of Riser =
12.500
cf
Less Opening for Barrel =
2.454
cf
Less Opening for Drain Pipe =
0.000
cf
Total Concrete Less Openings =
63.596
cf
Weight of Concrete =
1 9,031 jibs
AMOUNT OF WATER DISPLACED BY RISER STRUCTURE
Displacement by Concrete =
63.596
cf
Displacement by Open Air =
1 95.200
1 cf
Total Water Displaced =
158.796
cf
Weight of Water Displaced =
1 9,909
jibs
AMOUNT OF CONCRETE TO ADD TO RISER STRUCTURE
Safety Factor = 1.15
Add'I Weight for Bouyancy = 2,365 Ibs
Bouyant Weight of Concrete = 79.60 pcf
Bouyant Weight w/ SF = 69.22 pcf
Add'I Concrete to Add = 34.162 cf
Less Standard Base = 12.500 cf
New Base Design Required = 46.662 cf
ANTI FLOTATION BLOCK DESIGN CALCULATIONS
AF Block Length =
ft
AF Block Width =
ft
AF Block Thickness =
12.00
in
AF Block Provided =
49.000
cf
Total Concrete Present =
100.096
cf
=1
14,214 jibs
Date: 10/20/2020
Calculated By: J. Woodard, PE
Unit might of manhole concrete is 142 pcf per NC Products
Recommend 1.15 or higher

M McADaMs
DESIGN OF RIPRAP OUTLET PROTECTION WORKSHEET
Project:
7-Eleven - Long Ferry Road Date: 12/31/2020
Project Number:
CPR-20000 Calculated By: JBW
Outlet Number:
SCM-A
Outlet flowrate =
20
cfs (10-yr storm)
Pipe diameter =
15
inches
Number of pipes =
1
Pipe separation =
0
feet
Outlet Velocity =
5 ft/sec
Figure 8.06.b.1
25
20
Zone 6
U
15
10 zone 4
5
one
0
0 1 2 3 4 5 6 7 8 9 10
Pipe diameter (ft)
Zone from graph above =0
Outlet pipe diameter 15 in. Length = 5.0 ft.
Outlet flowrate 20.0 cfs Width = 3.3 ft.
Outlet velocity 5.0 ft/sec Stone diameter = 3 in.
Material = Class A Thickness = 12 in.
Zone
Material
Diameter
Thickness
Length
Width
1
Class A
3
12
4 x D(o)
3 x D(o)
2
Class 8
6
18
6 x D(o)
3 x D(o)
3
Class l
13
24
8 x D(o)
3 x D(o)
4
Class l
13
24
8 x D(o)
3 x D(o)
5
Class 11
23
36
10 x D(o)
3 x D(o)
6
Class 11
23
36
10 x D(o)
3 x D(o)
7
Special study required
1. Calculations based on Pages 8.06.05 through 8.06.06 in NC Erosion Control Manual
2. Outlet velocity based on full flow velocity

9 MCADAM
Subsection: Master Network Summary
Catchments Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft3)
Sub-1-to-SCM-A Post WQV 0 1 6,253.000 186.00 4.390
Sub-1-to-SCM-A Post 100 year 100 78,515.000 721.00 25.900
Node Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (min) (ft3/s)
(years) (ft3)
POA-1 Post WQV 0 6,253.000 298.00 0.159
POA-1 Post 100 year 100 69,743.000 722.00 23.961
Pond Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum
Event Volume (min) (ft3/s) Water Pond Storage
(years) (ft3) Surface (ft3)
Elevation
(ft)
SCM-A (IN)
Post WQV
0
6,253.000
186.00
4.390
(N/A)
(N/A)
SCM-A
Post WQV
0
6,253.000
298.00
0.159
704.13
4,683.000
(OUT)
SCM-A (IN)
Post 100 year
100
78,515.000
721.00
25.900
(N/A)
(N/A)
SCM-A
Post 100 year
100
69,743.000
722.00
23.961
705.48
11,210.000
(OUT)
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Elevation -Area Volume Curve
Label: SCM-A
Return Event: 0 years
Storm Event: 1 inch
Elevation Planimeter Area Al+A2+sqr Volume Volume (Total)
(ft) (ftz) (ftz) (Al*A2) (ft3) (ft3)
(ftz)
703.00
0.000
3,813.00
0.00
0.000
0.000
704.00
0.000
4,378.00
12,276.75
4,092.000
4,092.000
705.00
0.000
4,967.00
14,008.21
4,669.000
8,762.000
705.50
0.000
5,305.00
15,405.22
2,568.000
11,329.000
706.00
0.000
5,491.00
16,193.20
2,699.000
14,028.000
706.50
0.000
5,779.00
16,903.16
2,817.000
16,845.000
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Outlet Input Data
Label: SCM-A
Return Event: 0 years
Storm Event: 1 inch
Requested Pond Water Surface Elevations
Minimum (Headwater) 703.00 ft
Increment (Headwater) 0.50 ft
Maximum (Headwater) 706.50 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall E1 E2
(ft) (ft)
Inlet Box
Riser
Forward
Culvert
705.00
706.50
User Defined
Media
Forward
Culvert
0.00
706.50
Table
Culvert -Circular
Culvert
Forward
TW
699.15
706.50
Rectangular Weir
E-spill
Forward
TW
705.00
706.50
Tailwater Settings
I Tailwater
I
I
I (N/A)
(N/A)
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Outlet Input Data
Label: SCM-A
Structure ID: Culvert
Structure Type: Culvert -Circular
Number of Barrels
1
Diameter
15.000 in
Length
43.00 ft
Length (Computed Barrel)
43.04 ft
Slope (Computed)
0.044 ft/ft
Outlet Control Data
Manning's n
0.013
Ke
0.50
Kb
0.02
Kr
0.00
Convergence Tolerance
0.00 ft
Inlet Control Data
Equation Form
Form 1
K
0.0098
M
2.0000
C
0.0398
Y
0.6700
T1 ratio (HW/D)
1.14
T2 ratio (HW/D)
1.28
Slope Correction Factor
-0.50
Use unsubmerged inlet control 0 equation below T1
elevation.
Use submerged inlet control 0 equation above T2
elevation
In transition zone between unsubmerged and submerged
inlet control,
interpolate between flows at T1 & T2...
Return Event: 0 years
Storm Event: 1 inch
T1 Elevation 700.57 ft T1 Flow 4.802 ft3/s
T2 Elevation 700.76 ft T2 Flow 5.488 ft3/s
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Outlet Input Data
Label: SCM-A
Structure ID: Media
Structure Type: User Defined Table
Elevation Flow
(ft) (ft3/S)
Structure ID: Riser
Structure Type: Inlet Box
Number of Openings
1
Elevation
705.00 ft
Orifice Area
16.000 ftz
Orifice Coefficient
0.60
Weir Length
16.00 ft
Weir Coefficient
3.00 (ft^0.5)/s
K Reverse
1.00
Manning's n
0.00
Kev, Charged Riser
0.00
Weir Submergence
False
Orifice H to crest
False
Structure ID: E-spill
Structure Type: Rectangular Weir
Number of Openings
1
Elevation
705.00 ft
Weir Length
10.00 ft
Weir Coefficient
3.00 (ft^0.5)/s
Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type
Free Outfall
Convergence Tolerances
Maximum Iterations
30
Tailwater Tolerance
(Minimum)
0.01 ft
Tailwater Tolerance
(Maximum)
0.50 ft
7-11 Long Ferry
CPR20000.ppc
Return Event: 0 years
Storm Event: 1 inch
J. Woodard, PE
1 /15/2021

9 MCADAM
Subsection: Outlet Input Data Return Event: 0 years
Label: SCM-A Storm Event: 1 inch
Convergence Tolerances
Headwater Tolerance
0.01 ft
(Minimum)
Headwater Tolerance
0.50 ft
(Maximum)
Flow Tolerance (Minimum)
0.001 ft3/s
Flow Tolerance (Maximum)
10.000 ft3/s
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Level Pool Pond Routing Summary
Label: SCM-A (IN)
Infiltration
Infiltration Method No Infiltration
(Computed)
Initial Conditions
Elevation (Water Surface,
703.00 ft
Initial)
Volume (Initial)
0.000 ft3
Flow (Initial Outlet)
0.000 ft3/s
Flow (Initial Infiltration)
0.000 ft3/s
Flow (Initial, Total)
0.000 ft3/s
Time Increment
1.00 min
Inflow/Outflow Hydrograph Summary
Return Event: 0 years
Storm Event: 1 inch
Flow (Peak In) 4.390 ft3/s Time to Peak (Flow, In) 186.00 min
Flow (Peak Outlet) 0.159 ft3/s Time to Peak (Flow, Outlet) 298.00 min
Elevation (Water Surface,
704.13 ft
Peak)
Volume (Peak)
4,683.090 ft3
Mass Balance (ft3)
Volume (Initial)
0.000 ft3
Volume (Total Inflow)
6,253.000 ft3
Volume (Total Infiltration)
0.000 ft3
Volume (Total Outlet
6,253.000 ft3
Outflow)
Volume (Retained)
0.000 ft3
Volume (Unrouted)
0.000 ft3
Error (Mass Balance)
0.0 %
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021

9 MCADAM
Subsection: Level Pool Pond Routing Summary
Label: SCM-A (IN)
Infiltration
Infiltration Method No Infiltration
(Computed)
Initial Conditions
Elevation (Water Surface,
703.00 ft
Initial)
Volume (Initial)
0.000 ft3
Flow (Initial Outlet)
0.000 ft3/s
Flow (Initial Infiltration)
0.000 ft3/s
Flow (Initial, Total)
0.000 ft3/s
Time Increment
1.00 min
Inflow/Outflow Hydrograph Summary
Return Event: 100 years
Storm Event: 100 year
Flow (Peak In) 25.900 ft3/s Time to Peak (Flow, In) 721.00 min
Flow (Peak Outlet) 23.961 ft3/s Time to Peak (Flow, Outlet) 722.00 min
Elevation (Water Surface,
705.48 ft
Peak)
Volume (Peak)
11,209.504 ft3
Mass Balance (ft3)
Volume (Initial)
0.000 ft3
Volume (Total Inflow)
78,515.000 ft3
Volume (Total Infiltration)
0.000 ft3
Volume (Total Outlet
69,743.000 ft3
Outflow)
Volume (Retained)
8,756.000 ft3
Volume (Unrouted)
-17.000 ft3
Error (Mass Balance)
0.0 %
7-11 Long Ferry J. Woodard, PE
CPR20000. ppc 1 /15/2021