SW3231001_Design Calculations_20240209

MCBRIDE SUBDIVISION
HEMBY BRIDGE, NORTH CAROLINA
PROJECT CALCULATIONS
„„„IIIrrr ����.►►►►tkk CAiiii,*i
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NO. C-1069 ti
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Digitally signed by Anthony
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G5 B. Cowan, P.E.
Date: 2024.02.09
14:30:19-05'00'
ISAACS QC)
CIVIL ENGINEERING DESIGN & LAND SURVEYING C
8720 RED OAK BOULEVARD, STE. 420 -13
CHARLOTTE, N.C. 28217
PHONE [phone] FAX [phone]
NO. BY DA`L RIEUISION
1

TABLE OF CONTENTS
PROJECT NARRATIVE Page 3
STORM DRAINAGE CALCULATIONS
• STORM DRAINAGE CALCULATIONS Pages 4
• NOAA PRECIPITATION FREQUENCY Pages 5
• STORM DRAINAGE PIPE CALCULATIONS Pages 6-8
• STORM DRAINAGE HGL CALCULATIONS Pages 9-11
• STORM DRAINAGE PIPE TIME OF CONCENTRATION Pages 12-17
• DROP INLET CALCULATIONS Pages 18-19
• INLET SPREAD CALCULATIONS Pages 20-21
• HW/D CALCULATIONS Pages 22-23
• FES CALCULATIONS Pages 24-26
• SWALE CALCULATIONS Pages 27-39
EROSION CONTROL CALCULATIONS
• EROSOION CONTROL CALCULATIONS Pages 40
• SEDIMENT BASINS CALCULATIONS Pages 41-53
• SLOPE DRAIN HW/D CALCULATIONS Pages 54-55
• TEMPORARY DIVERSION DITCH CALCULATIONS Pages 56-64
BMP CALCULATIONS
• DETENTION WORKSHEET (WET POND & SAND FILTER) Page 65
o SUMMARY Page 66
o CN CALCS Pages 67-68
o Tc CALCS Page 69
o STAGE-STORAGE CALCS Page 70
o STAGE-DISCHARGE CALCS Page 71
• BMP 1 (WET POND)
o DESIGN PROCEDURE FORM Page 72
o CONCRETE ANCHOR BUOYANCY CALCULATIONS Page 73
• BMP 2 (SAND FILTER)
o DESIGN PROCEDURE FORM Pages 74-75
o CONCRETE ANCHOR BUOYANCY CALCULATIONS Page 76
• BMP ROUTING CALCULATIONS
o PONDPACK OUTPUT (1, 10, 25 & 100 yr-24hr) Pages 77-147

Project Narrative
Project Description
The project site is located in the Town of Hemby Bridge, Union County N.C. and is an
approximately 84.20 acre parcel along Idlewild Road (S.R. 1501). The proposed project
consists of One Hundred & eight (108) single family residential units, two driveway
accesses roads and two (2) BMP's designed in accordance with Union County, NCDEQ
and NCDOT requirements. The project area drains to the North Fork Crooked Creek,
which has regulated FEMA floodplain.
The Union County and NCDEQ requirements that have been met in the design of this
project include the treatment of the 1 inch storm, and in accordance with the Union County
Land use ordinance, 2 and 25 year detention is not required due to the proximity to the
flood plan.
The rainfall amounts used in the analysis of this project were obtained from current data
from NOAA.
Structural stormwater controls in the form of one Wet Pond and one sand filter SCM have
been provided to meet the following minimum requirements:
a. Remove an 85 percent average annual amount of Total Suspended Solids for the
1" rainfall event.
b. Storm water treatment systems shall be installed to control the difference in the
storm water runoff from the pre-development and post-development conditions
for the 1-year, 24-hour storm. Runoff volume drawdown time shall be a minimum
of 24 hours, but not more than 120 hours.
c. Meet design of Stormwater Management Measures set forth in 15A NCAC 02H
.1008.
Natural Resources Inventory
The parcel is covered in approximately 35% woods and 65% grass fields.
Existing on-site slopes range from 2 to 20 percent on average and existing soil types on
site are Tantum (TbB2) (Hydrologic group B), Secrest-Cid (ScA) (Hydrologic Group CID),
Chewacla (ChA) (Hydrologic group C) and Tarrus-Urban (TuB) (Hydrologic group B). Soil
and Forestry Services of the Carolinas.
Existing and Proposed Drainage Patterns
Proposed drainage patterns to the proposed on-site wet pond and sand filter BMPs are
maintaining existing drainage patterns to the maximum extent practicable as needed to
create a balanced distribution of storm water flow thru the wet pond and sand filter BMPs in
a consistent manner with existing flows.
Due to topographical constraints, a portion of the site is bypass. This area is denoted as
Drainage Area #3 on sheet C4.5 of the construction plans is (39.09 acres). This bypass
area is in floodplain areas below the site and BMPs and does not include any proposed
impervious area.
3

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
STORM DRAINAGE CALCULATIONS
Note: Refer to Construction Document sheet C5.0 for drainage area maps.
4

10/21/22, 1:26 PM P recipitation Frequency Data Server
NO PA Atlas 14,Volume 2,Version 3
`s'�`0 . Location name: Indian Trail,North Carolina,USA* it"'
'a''
Latitude:35.1113°, Longitude: -80.6373° none %
t M:i Elevation: 644.58 ft** 1, if
ob�mso- *source:ESRI Mks "-AN,.,,.,
**source:USG S
PO NT PRECIPITATIO NFREQ LENCY ESTIMATES
G M.Bonnin,D.M atin,B.Lin,T.Parzybok,M Yekta,and D.Riley
NO AA,National Weather Service,Silver Spring,M ayland
PF tabular I PF graphical I Maps & aerials
PF tabular
AM S-based point precipitation frequency estimates w Hi 90% confidence intervals (in
inches/hour)1
Annual exceedance probability(1/years)
Duration
1/21 /51 /101 /251 /501 /1001 /2001 /5001 /1000
5-m in5.40 6.66 7.42 8.24 8.78 9.25 9.68 10.2 10.5
(4.97-5.87) (6.12-7.25) (6.80-8.05) (7.52-8.93) (7.98-9.49) (8.39-10.0) (8.72-10.5) (9.07-11.0) (9.30-11.4)
10-m n 4.32 5.33 5.93 6.56 6.99 7.36 7.68 8.05 8.27
(3.97-4.70) (4.90-5.80) (5.44-6.44) (5.99-7.11) (6.35-7.57) (6.66-7.96) (6.91-8.32) (7.18-8.73) (7.33-8.99)_
15-m in3.62 4.50 5.00 5.55 5.90 6.20 6.46 6.75 6.93
(3.33-3.94) (4.13-4.89) (4.59-5.43) (5.07-6.01) (5.36-6.39) (5.61-6.71) (5.82-7.00) (6.02-7.32) (6.13-7.53)
30-min 2.50 3.19 3.63 4.11 4.44 4.75 5.03 5.37 5.61
(2.30-2.72) (2.94-3.47) (3.33-3.93) (3.76-4.45) (4.04-4.81) (4.30-5.14) (4.53-5.45) (4.79-5.83) (4.97-6.10)
160-Min 1 1.57 2.05 2.36 2.74 3.01 3.27 3.53 3.85 4.09
(1.44-1.71) (1.88-2.23) (2.17-2.56) (2.50-2.96) (2.74-3.26) (2.96-3.54) (3.18-3.82) (3.44-4.18) (3.63-4.45)
2-hr 0.911 1.20 1.39 1.63 1.81 1.98 2.15 2.38 2.55
(0.835-0.997) (1.10-1.31) (1.27-1.52) (1.48-1.78) (1.64-1.97) (1.78-2.16) (1.93-2.35) (2.11-2.60) (2.24-2.79)
3-hr 0.643 0.852 0.996 1.18 1.32 1.47 1.61 1.81 1.97
(0.589-0.707) (0.779-0.935) (0.907-1.09) (1.07-1.29) (1.19-1.44) (1.31-1.60) (1.43-1.76) (1.59-1.97) (1.71-2.15)_
6-hr 0.388 0.514 0.602 0.716 0.805 0.895 0.988 1.12 1.22
(0.356-0.425) (0.470-0.563) (0.549-0.658) (0.650-0.781) (0.725-0.875) (0.801-0.973) (0.875-1.07) (0.975-1.21) (1.05-1.32)_
12-hr 0.228 0.304 0.358 0.429 0.485 0.543 0.604 0.689 0.758
(0.210-0.251) (0.279-0.333) (0.327-0.392) (0.389-0.469) (0.436-0.529) (0.484-0.591) (0.532-0.656) (0.597-0.748) (0.648-0.823)
24-hr 0.135 0.180 0.212 0.254 0.287 0.320 0.355 0.403 0.442
(0.125-0.146) (0.167-0.195) (0.196-0.230) (0.234-0.275) (0.263-0.310) (0.293-0.346) (0.324-0.384) (0.366-0.437) (0.399-0.480)
2-day 0.079 0.105 0.123 0.147 0.165 0.184 0.204 0.231 0.253
(0.074-0.086) (0.097-0.114) (0.114-0.133) (0.135-0.159) (0.152-0.179) (0.169-0.199) (0.186-0.221) (0.209-0.251) (0.228-0.275)
3-day 0.056 0.074 0.086 0.102 0.115 0.128 0.142 0.161 0.176
(0.052-0.060) (0.068-0.080) (0.080-0.093) (0.095-0.111) (0.106-0.124) (0.118-0.138) (0.129-0.153) (0.146-0.174) (0.159-0.190)
4-day 0.044 0.058 0.068 0.080 0.090 0.100 0.111 0.125 0.137
(0.041-0.048) (0.054-0.062) (0.063-0.073) (0.074-0.086) (0.083-0.097) (0.092-0.108) (0.101-0.119) (0.114-0.135) (0.124-0.148)
7-day 0.029 0.038 0.044 0.051 0.057 0.064 0.070 0.079 0.086
(0.027-0.031) (0.035-0.040) (0.041-0.047) (0.048-0.055) (0.053-0.061) (0.059-0.068) (0.065-0.075) (0.072-0.085) (0.079-0.093)
10-day 0.023 0.030 0.034 0.040 0.044 0.048 0.053 0.059 0.064
(0.022-0.025) (0.028-0.032) (0.032-0.036) (0.037-0.042) (0.041-0.047) (0.045-0.052) (0.049-0.056) (0.054-0.063) (0.059-0.068)
20-day 0.015 0.019 0.022 0.025 0.028 0.030 0.033 0.037 0.039
(0.015-0.016) (0.018-0.021) (0.021-0.023) (0.024-0.027) (0.026-0.030) (0.029-0.032) (0.031-0.035) (0.034-0.039) (0.036-0.042)
30-day 0.013 0.016 0.017 0.020 0.022 0.023 0.025 0.027 0.029
(0.012-0.013) (0.015-0.016) (0.017-0.018) (0.019-0.021) (0.020-0.023) (0.022-0.025) (0.023-0.027) (0.026-0.029) (0.027-0.031)
45-day 0.011 0.013 0.014 0.016 0.017 0.018 0.020 0.021 0.022
(0.010-0.011) (0.012-0.013) (0.014-0.015) (0.015-0.017) (0.016-0.018) (0.017-0.019) (0.018-0.021) (0.020-0.022) (0.021-0.024)
60-day 0.009 0.011 0.012 0.014 0.015 0.016 0.017 0.018 0.019
(0.009-0.010) (0.011-0.012) (0.012-0.013) (0.013-0.014) (0.014-0.016) (0.015-0.017) (0.016-0.018) (0.017-0.019) (0.018-0.020)
1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of annual m adm a series(AM S).
Num hers in parenthesis are PF estim des at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency
estim des(for a given duration and annual exceedance probability)will be greater than the upper bound(or less than the lower bound)is 5%.
Estim des at upper bounds are not checked against probable m acim in precipitation(PM P)estim des and may be higher than currently valid PM P
values.
Please refer to NO PA Atlas 14 docum eit for m ae inform aion.
Back to Top
PF graphical
5
https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.htm Plat=35.1113&Ion=-80.6373&data=intensity&units=english&series=am s 14

25-YR EVENT STORM CAPACITY CALCULATIONS
From To Drainage Drainage Runoff Tc Tc Rain "I" Runoff"Q" Known Q Total Q Pipe Dia. Full Q Velocity Full Velocity Sec Time Invert Invert Crown Drop Slope
Area Inc Area Total Coeff"C" Design Elevation Elevation
_ u(s n/s _
(acre) (acre) (min) (min) (inch/hr) (cfs) (cfs) (cfs) (ft) (cfs) (ft/s) (ft/s) (min) (ft) (ft) (ft)
DI 1B FES 1A 0.67 17.95 0.60 5.00 8.73 7.28 2.92 0.00 79.94 3.50 77.14 8.02 9.10 0.37 635.50 634.50 N/A 0.50%
DCB 1C DI 1B 0.58 16.29 0.60 5.00 8.58 7.32 2.56 0.00 73.06 3.50 148.65 15.45 15.37 0.15 638.13 635.50 N/A 1.86%
CB 1F DCB 1C 0.18 15.71 0.85 5.00 8.54 7.33 1.14 0.00 70.58 3.50 88.79 9.23 10.23 0.04 639.23 639.08 N/A 0.66%
SLAB TYPE CB 1F 2.14 12.41 0.65 8.26 8.45 7.36 10.25 0.00 56.07 3.00 56.02 7.93 9.03 0.10 639.61 639.30 N/A 0.60%
SLAB TYPE
DI 2D CB 2C 0.45 10.27 0.60 5.00 7.83 7.52 2.04 0.00 46.77 3.00 56.02 7.93 8.86 0.62 641.78 639.81 N/A 0.60%
CB 2G DI 2D 0.12 2.20 0.60 5.00 5.62 8.12 0.57 0.00 10.83 1.50 8.88 5.03 6.13 0.25 645.17 644.61 N/A 0.61%
CB 2H CB 2G 0.14 1.57 0.60 5.00 5.34 8.20 0.67 0.00 7.77 1.50 8.82 4.99 5.63 0.28 646.45 645.87 N/A 0.60%
CB 3A CB 2H 0.32 1.43 0.60 5.00 5.27 8.22 1.58 0.00 7.11 1.25 6.48 5.28 5.80 0.07 646.84 646.65 N/A 0.86%
CB 3B CB 3A 0.52 1.11 0.60 5.00 5.10 8.26 2.60 0.00 5.55 1.25 6.34 5.16 5.82 0.17 648.81 648.32 N/A 0.82%
CB 3L CB 3B 0.59 0.59 0.60 5.00 5.00 8.29 2.92 0.00 2.94 1.25 5.40 4.40 4.49 0.10 649.17 649.01 N/A 0.59%
DI 2L CB 2G 0.52 0.52 0.60 5.00 5.00 8.29 2.58 0.00 2.61 1.25 13.40 10.92 8.45 0.09 648.73 647.04 N/A 3.66%
CB 2E DI 2D 0.50 7.61 0.60 5.00 7.55 7.60 2.26 0.00 35.03 3.00 56.02 7.93 8.36 0.28 642.81 641.98 N/A 0.60%
CB 2F CB 2E 0.49 7.12 0.60 5.00 7.50 7.61 2.22 0.00 32.81 3.00 55.34 7.83 8.15 0.05 643.15 643.01 N/A 0.59%
DI 2G CB 2F 0.45 6.63 0.60 5.00 7.22 7.69 2.06 0.00 30.88 3.00 56.14 7.94 8.13 0.29 644.19 643.35 N/A 0.60%
CB 7A DI 2G 0.42 6.18 0.60 5.00 7.05 7.73 1.97 0.00 28.97 3.00 67.68 9.57 9.20 0.17 645.19 644.39 N/A 0.88%
CB 7C CB 7A 0.33 5.76 0.60 5.00 7.02 7.74 1.53 0.00 27.02 2.50 54.37 11.08 11.05 0.04 645.74 645.39 N/A 1.49%
CB 7B CB 7C 0.05 4.92 0.70 5.00 6.66 7.84 0.26 0.00 23.35 2.50 43.06 8.77 8.94 0.35 647.72 645.94 N/A 0.94%
CB 7D CB 7B 0.14 4.87 0.60 5.00 6.60 7.86 0.64 0.00 23.14 2.50 57.99 11.81 11.14 0.06 648.65 647.92 N/A 1.70%
JB 7E CB 7D 0.07 4.37 0.60 5.00 6.46 7.90 0.33 0.00 20.88 2.50 80.28 16.36 13.74 0.14 652.62 648.85 N/A 3.26%
CB 7F JB 7E 0.53 0.99 0.60 5.00 5.36 8.19 2.63 0.00 4.91 1.50 19.50 11.04 9.18 0.12 655.82 653.85 N/A 2.93%
DI 7G CB 7F 0.46 0.46 0.60 5.00 5.00 8.29 2.27 0.00 2.28 1.25 9.89 8.06 6.55 0.36 658.82 656.02 N/A 1.99%
CB 7J JB 7E 0.27 3.31 0.60 5.00 6.39 7.91 1.29 0.00 15.85 2.00 53.13 16.91 14.75 0.07 655.68 652.81 N/A 4.69%
CB 7M CB 7J 0.04 3.04 0.60 5.00 6.12 7.99 0.20 0.00 14.69 2.00 41.05 13.07 11.97 0.27 663.53 658.10 N/A 2.80%
CB 7N CB 7M 0.28 2.59 0.60 5.00 6.05 8.01 1.36 0.00 12.54 2.00 19.00 6.05 6.46 0.07 665.56 665.39 N/A 0.60%
CB 7P CB 7N 0.28 2.31 0.60 5.00 5.99 8.02 1.34 0.00 11.19 2.00 19.00 6.05 6.29 0.06 665.90 665.76 N/A 0.60%
CB 7Q CB 7P 0.47 1.56 0.60 5.00 5.54 8.14 2.30 0.00 7.68 1.50 8.82 4.99 5.62 0.44 667.00 666.10 N/A 0.60%
CB 7R CB 7Q 0.52 1.09 0.60 5.00 5.47 8.16 2.54 0.00 5.38 1.25 5.43 4.42 5.04 0.07 667.33 667.20 N/A 0.60%
DI 7S CB 7R 0.57 0.57 0.60 5.00 5.00 8.29 2.83 0.00 2.86 1.25 6.28 5.12 4.99 0.47 668.66 667.53 N/A 0.80%
DI 7U CB 7P 0.47 0.47 0.60 5.00 5.00 8.29 2.33 0.00 2.35 1.25 6.27 5.11 4.74 0.49 668.90 667.77 N/A 0.80%
DI 7T CB 7M 0.41 0.41 0.60 5.00 5.00 8.29 2.03 0.00 2.05 1.25 5.43 4.42 4.11 0.57 665.12 664.28 N/A 0.60%
DI 7L CB 7D 0.36 0.36 0.60 5.00 5.00 8.29 1.79 0.00 1.80 1.25 9.91 8.07 6.13 0.10 651.26 650.50 N/A 2.00%
DI 7K CB 7C 0.52 0.52 0.60 5.00 5.00 8.29 2.56 0.00 2.58 1.25 8.55 6.97 6.10 0.08 647.16 646.73 N/A 1.49%
CB 2A CB 1F 0.41 1.04 0.60 5.00 5.08 8.27 2.04 0.00 5.22 1.25 10.53 8.58 8.56 0.25 643.29 640.38 N/A 2.26%
DBL CB 2B CB 2A 0.63 0.63 0.60 5.00 5.00 8.29 3.14 0.00 3.17 1.25 5.44 4.43 4.60 0.08 643.63 643.49 N/A 0.60%
CB 1G CB 1F 0.16 2.07 0.40 5.00 5.83 8.07 0.53 0.00 9.82 2.00 34.01 10.83 9.36 0.19 641.48 639.40 N/A 1.92%
CB 1H CB 1G 0.55 1.90 0.60 5.00 5.54 8.14 2.68 0.00 9.38 1.50 9.07 5.13 5.83 0.29 642.31 641.68 N/A 0.63%
CB 11 CB 1H 0.51 1.36 0.60 5.00 5.47 8.16 2.52 0.00 6.70 1.50 8.85 5.01 5.50 0.07 642.65 642.51 N/A 0.60%
DI 1J CB 11 0.84 0.84 0.60 5.00 5.00 8.29 4.19 0.00 4.22 1.50 8.82 4.99 4.94 0.47 643.68 642.84 N/A 0.60%
6

25-YR EVENT STORM CAPACITY CALCULATIONS
From To Drainage Drainage Runoff Tc Tc Rain "I" Runoff"Q" Known Q Total Q Pipe Dia. Full Q Velocity I Velocity Sec Time I Invert Invert Crown Slope
Area Inc Area Total Coeff"C" Full Design Elevation Elevation Drop
U/S D/S
(acre) (acre) (min) (min) (inch/hr) (cfs) (cfs) (cfs) (ft) (cfs) (ft/s) (ft/s) (min) (ft) (ft) (ft)
Dl 1D DI 1B 0.46 0.99 0.60 5.00 5.56 8.14 2.26 0.00 4.86 1.25 7.01 5.71 6.16 0.23 636.37 635.50 N/A 1.00%
DI 1P Dl 1D 0.52 0.52 0.60 5.00 5.00 8.29 2.60 0.00 2.63 1.25 9.86 8.03 6.79 0.56 645.28 640.77 N/A 1.98%
MH 1K FES 2 0.00 17.68 0.45 5.00 10.29 6.86 0.00 0.00 67.03 3.00 56.02 7.93 9.48 0.16 637.26 636.73 N/A 0.60%
DI 1L MH 1K 0.44 17.68 0.60 5.00 10.06 6.92 1.82 0.00 67.64 3.00 81.95 11.59 12.94 0.23 641.90 639.60 N/A 1.28%
Dl 3S Dl 1L 0.34 7.27 0.60 5.00 8.86 7.25 1.48 0.00 28.95 2.50 31.45 6.41 7.26 0.82 647.46 645.68 N/A 0.50%
CB 3R DI 3S 0.19 6.93 0.60 5.00 8.67 7.30 0.85 0.00 27.65 2.50 34.19 6.97 7.75 0.19 648.17 647.66 N/A 0.59%
CB 3Q CB 3R 0.04 6.73 0.60 5.00 8.47 7.35 0.16 0.00 26.98 2.50 34.54 7.04 7.78 0.20 648.93 648.37 N/A 0.60%
CB 3P CB 3Q 0.12 0.12 0.60 5.00 5.00 8.29 0.60 0 0.61 1.25 6.92 5.64 3.46 0.11 656.42 656.19 N/A 0.98%
CB 3M CB 3Q 0.10 6.57 0.70 5.00 8.10 7.45 0.53 0 26.65 2.50 34.45 7.02 7.74 0.37 650.17 649.13 N/A 0.60%
CB 3T CB 3M 0.12 3.60 0.70 5.00 7.27 7.68 0.63 0 15.04 2.00 31.70 10.09 9.95 0.22 652.53 650.37 N/A 1.67%
CB 4D CB 3T 0.05 3.08 0.70 5.00 7.09 7.72 0.28 0 12.62 2.00 19.00 6.05 6.47 0.18 652.92 652.51 N/A 0.60%
CB 4A CB 4D 0.11 3.03 0.70 5.00 6.86 7.79 0.59 0 12.43 2.00 19.00 6.05 6.44 0.23 653.66 653.12 N/A 0.60%
CB 4E CB 4A 0.34 1.09 0.60 5.00 6.78 7.81 1.60 0 4.28 1.25 5.43 4.42 4.90 0.08 654.36 654.23 N/A 0.60%
DI 4G CB 4E 0.75 0.75 0.45 6.20 6.20 7.97 2.69 0 2.72 1.25 5.43 4.42 4.42 0.58 655.49 654.56 N/A 0.60%
CB 4C CB 4A 0.22 1.83 0.70 5.00 5.55 8.14 1.27 0 7.92 1.50 10.19 5.77 6.37 0.48 655.58 654.12 N/A 0.80%
CB 4B CB 4C 0.58 1.60 0.60 5.00 5.48 8.16 2.85 0 6.65 1.25 5.43 4.42 5.42 0.07 655.92 655.78 N/A 0.60%
DI 4F CB 4B 1.02 1.02 0.45 5.00 5.00 8.29 3.81 0 3.84 1.25 5.43 4.42 4.79 0.48 656.95 656.12 N/A 0.60%
CB 3N CB 3T 0.40 0.40 0.60 5.00 5.00 8.29 2.00 0 2.02 1.25 7.01 5.71 4.93 0.08 653.36 653.13 N/A 1.00%
DCB 3H CB 3M 0.71 2.88 0.70 5.00 7.65 7.57 3.76 0 11.70 2.00 19.00 6.05 6.36 0.45 651.39 650.37 N/A 0.60%
DCB 3J I DCB 3H 0.18 2.17 0.60 5.00 7.59 7.59 0.82 0 7.93 2.00 19.00 6.05 5.77 0.06 651.73 651.59 N/A 0.60%
CB 5B DCB 3J 0.23 0.23 0.60 5.00 5.00 8.29 1.15 0 1.16 1.25 7.01 5.71 4.22 0.26 652.56 651.91 N/A 1.00%
FES 3K DCB 3J 1.75 1.75 0.45 7.54 7.54 7.60 6.00 0 6.05 2.00 50.32 16.02 10.80 0.05 653.00 651.72 N/A 4.21%
CB 1M DI 1L 0.51 9.98 0.60 5.00 9.78 6.99 2.15 0 38.57 3.00 55.99 7.92 8.53 0.27 646.43 645.60 N/A 0.60%
DBL CB 1N CB 1M 0.79 9.46 0.60 5.00 9.64 7.03 3.35 0 36.60 3.00 56.09 7.94 8.45 0.14 647.07 646.63 N/A 0.60%
CB 1P DBL CB 1N 0.13 0.13 0.60 5.00 5.00 8.29 0.66 0 0.67 1.25 7.10 5.78 3.63 0.11 649.91 649.67 N/A 1.03%
SLAB TYPE
CB 2M DBL CB 1N 1.12 8.54 0.45 9.19 9.19 7.15 3.60 0 33.22 2.50 34.45 7.02 7.99 0.45 648.56 647.27 N/A 0.60%
SLAB TYPE
DI 3G CB 2M 0.50 7.42 0.60 5.00 7.09 7.72 2.29 0 31.95 2.50 34.45 7.02 7.96 0.56 650.36 648.76 N/A 0.60%
FES 3G DI 3G 1.62 1.62 0.45 5.00 5.00 8.29 6.04 0 6.09 1.50 10.38 5.88 6.10 0.71 654.00 651.85 N/A 0.83%
CB 3C DI 3G 0.05 5.30 0.60 5.00 6.79 7.81 0.23 0 24.21 2.50 34.53 7.03 7.61 0.30 651.39 650.56 N/A 0.60%
CB 3D CB 3C 0.48 5.26 0.60 5.00 6.73 7.82 2.27 0 24.03 2.50 38.74 7.89 8.31 0.06 651.81 651.59 N/A 0.76%
CB 3E CB 3D 0.58 4.77 0.60 5.00 6.67 7.84 2.71 0 21.79 2.50 33.71 6.87 7.30 0.06 652.17 652.01 N/A 0.57%
Dl 3F CB 3E 0.59 0.59 0.60 5.00 5.00 8.29 2.94 0 2.96 1.50 8.84 5.00 4.50 0.51 653.19 652.36 N/A 0.60%
CB 5C CB 3E 0.04 3.60 0.60 5.00 6.14 7.98 0.20 0 16.55 2.00 29.08 9.26 9.55 0.53 656.61 652.36 N/A 1.41%
DI 5D CB 5C 0.63 0.63 0.60 5.00 5.00 8.29 3.15 0 3.18 1.25 6.10 4.97 5.02 0.46 658.61 657.56 N/A 0.76%
CB Si CB 5C 0.25 2.93 0.60 5.00 6.11 7.99 1.21 0 13.31 1.50 18.59 10.52 11.43 0.03 657.57 657.06 N/A 2.66%
CB 5K CB 5J 0.21 2.20 0.60 5.00 5.86 8.06 1.04 0 9.86 1.50 11.91 6.74 7.53 0.26 658.85 657.57 N/A 1.09%
CB 5L CB 5K 0.22 1.99 0.60 5.00 5.70 8.10 1.06 0 8.86 1.50 23.08 13.06 12.19 0.16 663.88 659.05 N/A 4.11%
CB 5H CB 5L 0.69 1.14 0.50 5.00 5.49 8.16 2.80 0 5.05 1.50 16.52 9.35 8.21 0.05 664.61 664.05 N/A 2.10%

25-YR EVENT STORM CAPACITY CALCULATIONS
From To Drainage Drainage Runoff Tc Tc Rain "I" Runoff"Q" Known Q Total Q Pipe Dia. Full Q Velocity Velocity Sec Time Invert Invert Crown Slope
Area Inc Area Total Coeff"C" Full Design Elevation Elevation Drop
U/S D/S
(acre) (acre) (min) (min) (inch/hr) (cfs) (cfs) (cfs) (ft) (cfs) (ft/s) (ft/s) (min) (ft) (ft) (ft)
DI 5N CB 5H 0.45 0.45 0.60 5.00 5.00 8.29 2.25 0 2.27 1.25 6.37 5.19 4.75 0.49 665.95 664.80 N/A 0.83%
CB 5M CB 5L 0.13 0.63 0.70 5.00 5.48 8.16 0.72 0 2.80 1.25 14.05 11.45 8.92 0.22 669.55 664.85 N/A 4.02%
CB 50 CB 5M 0.50 0.50 0.50 5.00 5.00 8.29 2.09 0 2.11 1.25 6.88 5.61 4.93 0.48 671.11 669.75 N/A 0.97%
CB 5E CB 5J 0.48 0.48 0.60 5.00 5.00 8.29 2.38 0 2.40 1.50 11.87 6.72 5.26 0.09 657.89 657.57 N/A 1.09%
DI 6B FES 6A 0.51 4.73 0.60 5.00 6.38 7.92 2.41 0 22.15 3.00 53.47 7.57 7.20 0.14 638.33 638.00 N/A 0.55%
DBL CB 6C DI 6B 0.47 4.22 0.60 5.00 6.02 8.01 2.26 0 19.96 2.50 34.51 7.03 7.28 0.36 639.82 638.89 N/A 0.60%
DBL CB 6D DBL CB 6C 0.62 3.76 0.60 5.00 5.96 8.03 3.00 0 17.72 2.50 33.70 6.86 6.95 0.06 642.00 641.86 N/A 0.57%
CB 6E DBL CB 6D 0.36 0.60 0.60 5.00 5.11 8.26 1.78 0 3.00 1.25 11.72 9.55 7.98 0.49 648.79 642.25 N/A 2.80%
CB 6F CB 6E 0.24 0.24 0.60 5.00 5.00 8.29 1.19 0 1.20 1.25 5.43 4.42 3.55 0.11 650.41 650.27 N/A 0.60%
SLAB TYPE
CB 61 DBL CB 6D 0.64 1.96 0.60 5.00 5.55 8.14 3.15 0 9.00 1.50 8.84 5.00 5.69 0.41 643.39 642.55 N/A 0.60%
SLAB TYPE
DI 6J CB 61 0.45 0.45 0.60 5.00 5.00 8.29 2.22 0 2.24 1.25 9.27 7.55 6.22 0.19 644.84 643.59 N/A 1.75%
SLAB TYPE
DI 6K CB 61 0.52 0.87 0.45 5.00 5.31 8.21 1.93 0 3.65 1.25 14.18 11.56 9.68 0.24 649.28 643.59 N/A 4.10%
D16L DI 6K 0.34 0.34 0.60 5.00 5.00 8.29 1.70 0 1.72 1.25 5.43 4.42 3.92 0.31 649.92 649.48 N/A 0.60%
CB 6G DBL CB 6D 0.44 0.57 0.60 5.00 5.12 8.26 2.19 0 2.98 1.25 5.84 4.76 4.78 0.24 643.85 643.38 N/A 0.70%
CB 6H CB 6G 0.13 0.13 0.70 5.00 5.00 8.29 0.77 0 0.78 1.25 5.43 4.42 3.14 0.12 644.19 644.05 N/A 0.60%
From To Drainage Drainage Runoff Tc Tc Rain "I" Runoff"Q" Known Q Total Q Pipe Dia. Full Q Velocity Velocity Sec Time Invert Invert Crown Slope
Area Inc Area Total Coeff"C" Full Design Elevation Elevation Drop
U/S D/S
(acre) (acre) (min) (min) (inch/hr) (cfs) (cfs) (cfs) (ft) (cfs) (ft/s) (ft/s) (min) (ft) (ft) (ft)
DI RD2 FES RD1 0.84 4.11 0.4 5 5.11 8.26 2.78 0 13.708 1.5 14.041 7.946 9.047 0.079 667.86 667.21 N/A 1.52%
COLLAR DI RD2 0.00 3.27 0 0 5.072 8.271 0.00 0 10.918 1.5 14.272 8.076 8.891 0.038 669.7 669.38 N/A 1.57%
CULVERT
RD4 COLLAR 3.27 3.27 0.40 5.00 5.00 8.29 10.85 0 10.94 1.50 14.27 8.08 8.90 0.07 670.30 669.70 N/A 1.57%
HW 8B HW 8A 10.02 10.02 0.45 24.25 24.25 4.686 21.304 0 21.304 3 112.046 15.851 12.192 0.138 641.38 638.96 N/A 2.40%
8
8

25-YR STORM HGL CALCULATIONS
Struct.ID D Q L V d do vA2/2g EGLo HGLo Sf Total EGLi HGLi Ea EGLa U/S TOC Surface
Pipe Loss Elev.
(ft) (csf) (ft) (ft/s) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft)
FES 1A 636.5 636.5 638.00 638.46
DI 1B 3.5 79.94 200.65 9.10 3.00 2.79 1.29 638.79 637.5 0.005 1.0 639.79 638.5 5.65 641.15 639.00 643.25
DCB 1C 3.5 73.06 141.49 7.59 1.73 2.68 0.9 641.51 640.61 0.004 0.6 642.14 641.25 4.72 642.84 642.58 646.35
CB 1F 3.5 70.58 23.99 7.34 2.36 2.63 0.84 643.18 642.34 0.004 0.1 643.28 642.44 4.85 644.09 642.30 646.35
SLAB TYPE CB 2C 3 56.07 51.55 7.93 3.00 n/a 0.98 644.48 643.5 0.006 0.3 644.79 643.81 5.40 645.01 642.81 645.91
DI 2D 3 46.77 328.44 6.62 _3.00 n/a 0.68 645.29 644.61 0.004 1.4 646.66 645.98 5.31 647.09 644.98 650.60
CB 2G 1.5 10.83 92.17 6.13 1.50 n/a 0.58 647.33 646.74 0.009 0.8 648.16 647.58 3.40 648.58 648.29 652.51
CB 2H 1.5 7.77 95.15 4.40 1.50 n/a 0.3 648.7 648.39 0.005 0.4 649.14 648.84 2.94 649.38 647.90 651.75
CB 3A 1.25 7.11 22.50 5.80 1.25 n/a 0.52 649.59 649.07 0.010 0.2 649.83 649.3 3.26 650.10 649.57 651.75
CB 3B 1.25 5.55 60.49 4.52 1.25 n/a 0.32 650.23 649.91 0.006 0.4 650.61 650.29 1.98 650.79 650.26 652.98
CB 3L 1.25 2.94 26.51 2.40 1.25 n/a 0.09 650.82 650.73 0.002 0.1 650.87 650.78 1.75 650.92 --- 652.98
DI 2L 1.25 2.61 46.09 8.45 0.37 0.65 1.11 648.6 648.53 0.001 0.0 650.21 649.1 1.48 650.21 --- 652.51
CB 2E 3 35.03 138.57 4.96 3.00 n/a 0.38 647.25 646.86 0.002 0.3 647.57 647.19 4.84 647.65 646.01 651.08
CB 2F 3 32.81 23.92 4.64 3.00 n/a 0.33 647.79 647.45 0.002 0.1 647.84 647.5 4.76 647.91 646.35 651.08
DI 2G 3 30.88 138.73 4.37 3.00 n/a 0.3 648.03 647.73 0.002 0.3 648.28 647.99 4.33 648.52 647.39 650.19
CB 7A 3 28.97 91.59 4.10 3.00 n/a 0.26 648.63 648.36 0.002 0.2 648.77 648.51 3.64 648.83 647.89 650.78
CB 7C 2.5 27.02 23.67 5.50 2.50 n/a 0.47 649.02 648.55 0.004 0.1 649.1 648.63 3.72 649.47 647.98 650.79
CB 7B 2.5 23.35 189.87 4.76 1.31 1.64 0.35 649.61 649.26 0.003 0.5 650.13 649.78 2.62 650.34 650.42 652.73
CB 7D 2.5 23.14 43.04 11.14 1.10 1.64 1.93 650.48 650.13 0.000 0.0 651.68 649.75 3.03 651.68 651.35 653.94
JB 7E 2.5 20.88 115.77 13.74 0.87 1.55 2.93 651.79 651.51 0.002 0.0 656.42 653.49 3.80 656.42 655.35 658.41
CB 7F 1.5 4.91 67.28 9.18 0.51 0.85 1.31 656.47 656.35 0.002 0.0 657.65 656.34 1.82 657.65 657.27 660.96
DI 7G 1.25 2.28 140.52 6.55 0.41 0.60 0.67 657.67 657.61 0.001 0.0 659.9 659.23 1.08 659.90 --- 661.48
CB 7J 2 15.85 61.20 14.75 0.75 1.44 3.38 656.58 656.19 0.004 0.0 659.81 656.43 4.13 659.81 660.10 662.64
CB 7M 2 14.69 194.02 11.97 0.83 1.38 2.23 659.98 659.57 0.000 0.0 666.58 664.36 3.05 666.58 667.39 670.30
CB 7N 2 12.54 27.06 6.46 1.19 1.27 0.65 667.23 666.58 0.000 0.0 667.39 666.74 2.45 668.00 667.76 670.90
CB 7P 2 11.19 23.45 3.56 2.00 n/a 0.2 668.08 667.88 0.002 0.1 668.13 667.93 2.36 668.25 667.60 671.05
CB 7Q 1.5 7.68 149.79 4.35 1.50 n/a 0.29 668.37 668.08 0.005 0.7 669.05 668.76 2.28 669.28 668.45 673.40
CB 7R 1.25 5.38 22.50 4.38 1.25 n/a 0.3 669.4 669.1 0.006 0.1 669.53 669.23 2.35 669.68 668.78 673.42
DI 75 1.25 2.86 140.35 2.33 0.59 0.68 0.08 669.71 669.63 0.002 0.2 669.94 669.86 1.33 669.99 --- 672.08
DI 7U 1.25 2.35 140.51 4.74 0.53 0.61 0.35 668.65 668.3 0.000 0.0 669.78 669.43 0.93 669.82 --- 671.83
DI 7T 1.25 2.05 140.48 1.67 1.25 n/a 0.04 666.6 666.56 0.001 0.1 666.72 666.68 1.62 666.74 --- 668.37
DI 7L 1.25 1.80 38.18 6.13 0.36 0.53 0.58 651.69 651.66 0.000 0.0 652.21 651.63 0.95 652.21 --- 660.01
DI 7K 1.25 2.58 28.58 2.11 1.25 n/a 0.07 649.49 649.43 0.001 0.0 649.53 649.46 2.41 649.57 --- 651.96
CB 2A 1.25 5.22 128.72 4.26 1.25 n/a 0.28 644.2 643.92 0.006 0.7 644.92 644.64 1.85 645.14 644.74 648.13
DBL CB 2B 1.25 3.17 22.42 2.58 1.25 n/a 0.1 645.18 645.08 0.002 0.1 645.23 645.12 1.67 645.30 --- 648.13
89

25-YR STORM HGL CALCULATIONS
Struct.ID D Q L V d do vA2/2g EGLo HGLo Sf Total EGLi HGLi Ea EGLa U/S TOC Surface
Pipe Loss Elev.
(ft) (csf) (ft) (ft/s) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft)
CB 1G 2.00 9.82 108.07 3.13 2.00 n/a 0.15 644.15 644.00 0.00 0.17 644.32 644.17 2.93 644.40 643.18 647.79
CB 1H 1.50 9.38 100.23 5.31 1.50 n/a 0.44 644.58 644.14 0.01 0.68 645.26 644.82 3.27 645.58 644.01 649.89
CB 11 1.50 6.70 22.37 3.79 1.50 n/a 0.22 645.67 645.45 0.00 0.08 645.75 645.53 3.20 645.84 644.34 649.89
DI 1J 1.50 4.22 139.47 2.39 _1.50 n/a 0.09 645.88 645.79 0.00 0.19 646.07 645.98 2.43 646.11 --- 647.65
DI 1D 1.25 4.86 86.46 3.96 1.25 n/a 0.24 641.25 641.00 0.01 0.42 641.66 641.42 5.38 641.75 642.02 643.34
DI 1P 1.25 2.63 228.00 6.79 0.44 0.65 0.72 641.79 641.69 0.00 0.00 646.44 645.72 1.16 646.44 --- 648.72
FES 2 636.50 636.50 639.73 640.15
MH 1K 3.00 67.03 89.07 9.48 3.00 n/a 1.40 641.13 639.73 0.01 0.53 641.66 640.26 4.88 642.14 642.60 655.74
DI 1L 3.00 67.64 179.63 12.94 2.08 2.62 2.60 644.28 641.68 0.00 0.00 646.59 643.98 4.78 646.68 648.60 655.66
DI 35 2.50 28.95 356.78 7.26 1.89 1.83 0.82 648.39 647.57 0.01 1.78 650.17 649.35 3.46 650.92 650.67 657.70
CB 3R 2.50 27.65 86.67 5.63 2.50 n/a 0.49 651.12 650.62 0.00 0.34 651.45 650.96 3.60 651.78 651.43 659.66
CB 3Q 2.50 26.98 91.46 5.50 2.50 n/a 0.47 651.97 651.50 0.00 0.34 652.30 651.83 3.78 652.71 657.44 660.02
CB 3P 1.25 0.61 23.09 3.46 0.25 0.30 0.19 656.63 656.44 0.00 0.00 656.85 656.67 0.44 656.85 --- 660.06
CB 3M 2.50 26.65 173.52 5.43 2.50 n/a 0.46 652.89 652.43 0.00 0.62 653.52 653.06 3.58 653.75 652.37 658.04
CB 3T 2.00 15.04 129.82 4.79 0.97 1.40 0.36 653.89 653.54 0.00 0.49 654.38 654.03 2.53 655.07 654.51 656.93
CB 4D 2.00 12.62 69.38 4.02 2.00 n/a 0.25 655.17 654.92 0.00 0.18 655.35 655.10 2.49 655.41 655.12 657.37
CB 4A 2.00 12.43 90.26 3.96 1.18 1.27 0.24 655.51 655.27 0.00 0.23 655.74 655.50 2.20 655.86 655.62 658.14
CB 4E 1.25 4.28 22.68 3.49 1.25 n/a 0.19 655.94 655.75 0.00 0.08 656.02 655.84 1.72 656.09 655.81 658.14
DI 4G 1.25 2.72 153.65 2.21 0.63 0.66 0.08 656.12 656.04 0.00 0.23 656.35 656.27 1.17 656.65 --- 658.24
CB 4C 1.50 7.92 183.04 6.37 0.99 1.09 0.63 655.99 655.68 0.01 0.00 657.21 656.58 2.30 657.88 657.03 659.96
CB 4B 1.25 6.65 22.50 5.42 1.25 n/a 0.46 658.07 657.61 0.01 0.20 658.27 657.81 2.49 658.41 657.37 659.96
DI 4F 1.25 3.84 138.63 3.13 1.25 n/a 0.15 658.47 658.32 0.00 0.42 658.89 658.74 1.99 658.94 --- 659.70
CB 3N 1.25 2.02 22.81 1.65 1.25 n/a 0.04 655.08 655.04 0.00 0.02 655.10 655.06 1.76 655.12 --- 656.93
DCB 3H 2.00 11.70 170.96 3.73 2.00 n/a 0.22 653.84 653.62 0.00 0.39 654.23 654.01 2.98 654.37 653.59 655.84
DCB 3J 2.00 7.93 22.33 2.52 2.00 n/a 0.10 654.41 654.31 0.00 0.02 654.44 654.34 2.75 654.48 653.72 655.98
CB 5B 1.25 1.16 64.99 0.95 1.25 n/a 0.01 654.49 654.47 0.00 0.02 654.51 654.49 1.95 654.51 --- 656.31
FES 3K 2.00 6.05 30.46 1.93 0.47 0.87 0.06 654.50 654.45 0.00 0.02 654.52 654.47 1.54 654.54 --- 655.33
CB 1M 3.00 38.57 139.86 8.53 1.83 2.02 1.13 648.56 647.43 0.00 0.00 649.40 648.27 3.34 649.77 649.63 656.79
DBL CB 1N 3.00 36.60 73.23 5.18 1.77 1.97 0.42 649.94 649.52 0.00 0.19 650.13 649.71 3.20 650.28 650.92 655.63
CB 1P 1.25 0.67 23.43 3.63 0.26 0.32 0.20 650.28 650.26 0.00 0.00 650.37 650.17 0.46 650.37 --- 655.63
SLAB TYPE CB 2M 2.50 33.22 214.91 6.77 1.97 1.96 0.71 650.56 649.85 0.01 1.20 651.76 651.05 3.71 652.27 651.26 654.59
DI 3G 2.50 31.95 266.47 6.51 2.50 n/a 0.66 652.54 651.88 0.01 1.38 653.92 653.26 4.01 654.38 653.35 656.44
FES 3G 1.50 6.09 258.94 3.45 0.83 0.95 0.18 654.45 654.27 0.00 0.74 655.19 655.01 1.56 655.56 --- 655.79
CB 3C 2.50 24.21 137.96 4.93 2.50 n/a 0.38 654.53 654.15 0.00 0.41 654.94 654.56 3.86 655.25 654.09 656.55
CB 3D 2.50 24.03 28.66 4.90 2.50 n/a 0.37 655.40 655.03 0.00 0.08 655.49 655.11 3.97 655.78 654.51 656.95
CB 3E 2.50 21.79 27.68 4.44 2.50 n/a 0.31 655.90 655.60 0.00 0.07 655.97 655.66 4.02 656.19 654.36 656.96
10
10

25-YR STORM HGL CALCULATIONS
Struct.ID D Q L V d do vA2/2g EGLo HGLo Sf Total EGLi HGLi Ea EGLa U/S TOC Surface
Pipe Loss Elev.
(ft) (csf) (ft) (ft/s) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (ft)
DI 3F 1.50 2.96 137.53 1.68 1.50 n/a 0.04 656.21 656.16 0.00 0.09 656.30 656.26 3.12 656.31 --- 656.63
CB 5C 2.00 16.55 302.57 9.55 1.08 1.47 1.42 656.36 655.93 0.01 0.00 659.11 657.69 2.50 659.11 658.81 661.17
DI 5D 1.25 3.18 137.86 2.59 0.64 0.72 0.10 659.15 659.04 0.00 0.28 659.43 659.33 1.52 660.13 --- 661.61
CB 5J 1.50 13.31 _19.44 11.43 0.94 1.36 2.03 659.46 658.58 0.01 0.00 660.54 658.51 2.97 660.54 659.07 661.45
CB 5K 1.50 9.86 116.22 5.58 1.50 n/a 0.48 660.74 660.25 0.01 0.87 661.61 661.13 2.92 661.76 660.55 663.84
CB 5L 1.50 8.86 117.70 12.19 0.65 1.15 2.31 661.92 661.53 0.01 0.00 666.84 664.53 2.96 666.84 665.55 668.42
CB 5H 1.50 5.05 26.50 2.86 1.50 n/a 0.13 666.89 666.76 0.00 0.05 666.94 666.81 2.37 666.98 666.05 668.42
DI 5N 1.25 2.27 138.77 1.85 0.52 0.60 0.05 667.00 666.95 0.00 0.15 667.15 667.09 1.22 667.17 --- 669.23
CB 5M 1.25 2.80 117.07 8.92 0.38 0.67 1.24 666.87 666.79 0.00 0.00 671.17 669.93 1.62 671.17 671.00 673.33
CB 50 1.25 2.11 140.73 4.93 0.47 0.58 0.38 671.18 671.14 0.00 0.00 671.96 671.58 0.85 671.96 --- 675.08
CB 5E 1.50 2.40 28.91 1.36 1.50 n/a 0.03 660.56 660.53 0.00 0.01 660.57 660.54 2.69 660.58 --- 661.60
FES 6A _ 0.00 0.00 641.00 641.42
DI 6B 3.00 22.15 60.55 7.20 1.35 1.51 0.81 640.15 639.35 0.00 0.00 640.48 639.68 2.47 640.80 641.39 648.15
DBL CB 6C 2.50 19.96 156.04 7.28 1.37 _ 1.52 0.82 640.95 640.57 0.00 0.00 642.01 641.19 2.49 642.31 644.36 647.06
DBL CB 6D 2.50 17.72 23.33 6.95 1.29 1.42 0.75 643.90 643.15 0.00 0.00 644.04 643.29 2.36 644.36 643.50 647.06
CB 6E 1.25 3.00 233.52 7.98 0.43 0.70 0.99 644.40 644.30 0.00 0.00 650.21 649.22 1.42 650.21 651.52 653.98
CB 6F 1.25 1.20 22.50 3.55 0.40 0.43 0.20 650.87 650.67 0.00 0.00 651.00 650.81 0.60 651.00 --- 653.98
SLAB TYPE CB 61 1.50 9.00 140.13 5.09 1.50 n/a 0.40 644.52 644.12 0.01 0.88 645.39 644.99 2.27 645.66 644.84 647.37
DI 6J 1.25 2.24 71.59 1.83 0.42 0.60 0.05 645.68 645.63 0.00 0.07 645.76 645.71 0.94 645.79 --- 648.08
DI 6K 1.25 3.65 138.86 9.68 0.43 0.77 1.46 645.72 645.58 0.00 0.00 651.17 649.72 1.89 651.17 650.73 653.42
DI 6L 1.25 1.72 73.35 I 1.40 1.25 n/a 0.03 651.18 651.15 0.00 0.04 651.23 651.20 1.32 651.24 --- 653.32
CB 6G 1.25 2.98 67.66 4.78 0.63 0.69 0.36 644.41 644.28 0.00 0.00 644.84 644.49 1.21 645.06 645.30 647.75
CB 6H 1.25 0.78 22.50 3.14 0.32 0.35 0.15 645.07 645.06 0.00 0.00 645.07 644.91 0.88 645.07 --- 647.75
HW 8B 3 21.304 101.03 12.192 0.89 1.48 2.31 643.73 643.51 0 0 644.58 642.27 3.2 644.58 --- 644.9
FES RD1 0.00 0.00 668.71 669.00
DI RD2 1.50 13.71 42.94 9.05 1.20 1.37 1.27 669.68 668.41 0.00 0.00 670.33 669.06 2.74 670.61 670.88 671.49
Structure-(237) 1.50 10.92 20.14 8.89 0.98 1.27 1.23 671.59 670.36 0.00 0.00 671.91 670.68 2.22 671.92 671.20 672.41
CULVERT RD4 1.50 10.94 38.37 6.19 1.50 n/a 0.60 672.16 671.56 0.01 0.35 672.51 671.91 2.33 672.63 --- 672.09
11
11

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Tt)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
SLAB TYPE CB 2C Post Developed
Check one: 0 Te ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 50
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.04
0.007 (nL)°8 Compute Tt hr 0.098 + + = 0.098 hr.
6. Tt= o.e 0 4
P2 s 5.86 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 390
9. Watercourse slope, s ft/ft 0.028
10. Average velocity, V(figure 3-1) ft/s 2.70
L Compute Tt hr 0.040 + + = 0.040 hr.
11. Tt=
3600 V 2.41 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.14 hr I
8.26 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-$E 61R T 2C-Tc
12

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Tt)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
SLAB TYPE CB 2M Post Developed
Check one: 0 Tc ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 50
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.022
_ 0.007 (nL)°8 Compute Tt hr 0.124 + + = 0.124 hr.
-
6. Tt o.e 0 4
P2 s 7.44 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 284
9. Watercourse slope, s ft/ft 0.028
10. Average velocity, V(figure 3-1) ft/s 2.70
L Compute Tt hr 0.029 + + = 0.029 hr.
11. Tt= -
3600 V 1.75 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.15 hr I
9.19 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-31M135I t9EDBs2M-Tc
13

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Ti)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
SLAB TYPE CB 3G Post Developed
Check one: 0 Tc ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 50
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.042
0.007 (nL)°8 Compute Tt hr 0.096 + + = 0.096 hr.
6. Tt= o.e 0 4
P2 s 5.74 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 334
9. Watercourse slope, s ft/ft 0.026
10. Average velocity, V(figure 3-1) ft/s 2.60
L Compute Tt hr 0.036 + + = 0.036 hr.
11. Tt=
3600 V 2.14 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.13 hr I
7.88 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-TR-55 SIDIEERII 3G-Tc
14

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Ti)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
SLAB TYPE CB 3K Post Developed
Check one: 0 Tc ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 50
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.036
_ 0.007 (nL)°8 Compute Tt hr 0.102 + + = 0.102 hr.
-
6. Tt o.e 0 4
P2 s 6.11 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 280
9. Watercourse slope, s ft/ft 0.041
10. Average velocity, V(figure 3-1) ft/s 3.27
L Compute Tt hr 0.024 + + = 0.024 hr.
11. Tt= —
3600 V 1.43 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.13 hr I
7.54 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-TR-55$TC3a3K -Tc
15

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Tt)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
DI 3U Post Developed
Check one: 0 Tc ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 50
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.05
_ 0.007 (nL)°8 Compute Tt hr 0.089 + + = 0.089 hr.
-
6. Tt o.e 0 4
P2 s 5.36 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 220
9. Watercourse slope, s ft/ft 0.073
10. Average velocity, V(figure 3-1) ft/s 4.36
L Compute Tt hr 0.014 + + = 0.014 hr.
11. Tt= —
3600 V 0.84 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.10 hr I
6.20 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-TR-55 POSTDdIs9U -Tc
16

TR-55 Worksheet 3: Time of Concentration (Ta) or Travel Time (Ti)
Project By Date
McBride Subdivision AEN 6/24/2022
Location Checked Date
Union County
FES 8B Post Developed
Check one: 0 Tc ❑ Tt through subarea
Note:Space for as many as three segments per flow type can be used for each worksheet. Include a map,
schematic,or description of flow segments.
Segment ID AB
1. Surface description (table 3-1) Dense Grass
2. Manning's roughness coefficient, n (table 3-1) 0.24
3. Flow length, L (total L<_ 100 ft) ft 100
4. Two-year 24-hour rainfall, P2 in 3.6
5. Land slope, s ft/ft 0.013
_ 0.007 (nL)°8 Compute Tt hr 0.266 + + = 0.266 hr.
-
6. Tt o.e 0 4
P2 s 15.98 min.
Shallow concentrated flow
Segment ID BC
7. Surface description (paved or unpaved) Unpaved
8. Flow length, L ft 1290
9. Watercourse slope, s ft/ft 0.026
10. Average velocity, V(figure 3-1) ft/s 2.60
L Compute Tt hr 0.138 + + = 0.138 hr.
11. Tt= -
3600 V 8.26 min.
20. Watershed or subarea T,or Tt (add Tt in steps 6, 11 and 19) 0.40 hr I
24.25 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\22006-TR-55 POSERS 8B-Tc
17

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
DROP INLET
CALCULATIONS
18

10 YR YARD INLET DEPTH
Name Drain. Runoff Time of Rainfall Q=CIA/Kc Cross Cross Total Depth d Gutter Spread W/T Grate Grate Intercept
Area A Coeff.C Conc. Intens. Slope Sx Slope Sw Gutter Width T Length Width Flow Qi
Flow
(acres) (min) (inch/hr) (cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (cfs)
DI 1D 0.48 0.6 5 7.51 2.16 0.02 0.05 2.16 0.27 2 10.478 0.191 3 2 2.16
DI 1C 0.67 0.6 5 7.51 3.042 0.02 0.05 3.042 0.326 2 13.29 0.15 3 2 3.042
DI 1P 0.52 0.6 5 7.51 2.378 0.02 0.05 2.378 0.284 2 11.202 0.179 3 2 2.378
DI 2D 0.45 0.6 5 7.51 2.058 0.02 0.05 2.058 0.263 2 10.128 0.197 3 2 2.058
SLAB TYPE CB 2C 2.16 0.45 8.25 6.714 6.591 0.02 0.05 6.591 0.422 2 18.122 0.11 4 4 6.591
DI 2L 0.52 0.6 5 7.51 2.36 0.02 0.05 2.36 0.283 2 11.144 0.179 3 2 2.36
DI 7G 0.46 0.6 5 7.51 2.069 0.02 0.05 2.069 0.263 2 10.167 0.197 3 2 2.069
DI 7S 0.571 0.6 5 7.51 2.587 0.02 0.05 2.587 0.298 2 11.878 0.168 3 2 2.587
DI 7U 0.47 0.6 5 7.51 2.13 0.02 0.05 2.13 0.268 2 10.375 0.193 3 2 2.13
DI 7T 0.41 0.6 5 7.51 1.857 0.02 0.05 1.857 0.248 2 9.424 0.212 3 2 1.857
DI 7H 0.45' 0.6 5 7.51 2.032 0.02 0.05 2.032 0.261 2 10.037 0.199 3 2 2.032
DI 7K 0.52 0.6 5 7.51 2.341 0.02 0.05 2.341 0.282 2 11.081 0.18 3 2 2.341
DI 7L 0.36 0.6 5 7.51 1.632 0.02 0.05 1.632 0.232 2 8.605 0.232 3 2 1.632
DI 1G 0.74 0.6 5 7.51 3.368 0.02 0.05 3.368 0.345 2 14.26 0.14 3 2 3.368
DI 1R 0.38 0.6 5 7.51 1.729 0.02 0.05 1.729 0.239 2 8.963 0.223 3 2 1.729
SLAB TYPE CB 3K 1.75 0.45 7.5 6.897 5.491 0.02 0.05 5.491 0.421 2 18.041 0.111 3 3 5.491
SLAB TYPE CB 3G 1.58 0.45 7.85 6.812 4.877 0.02 0.05 4.877 0.314 2 12.69 0.158 4 4 4.877
DI 3F 0.50 0.6 5 7.51 2.25 0.02 0.05 2.25 0.276 2 10.779 0.186 3 2 2.25
SLAB TYPE CB 2M 1.09 0.45 9 6.53 3.237 0.02 0.05 3.237 0.298 2 11.898 0.168 5 5 3.237
DI SD 0.63 0.6 5 7.51 2.88 0.02 0.05 2.88 0.316 2 12.796 0.156 3 2 2.88
DI 5J 0.45 0.6 5 7.51 2.054 0.02 0.05 2.054 0.262 2 10.115 0.198 3 2 2.054
DI 4F 1.02 0.45 5 7.51 3.479 0.02 0.05 3.479 0.352 2 14.583 0.137 3 2 3.479
DI 4G 0.75 0.45 6.2 7.216 2.46 0.02 0.05 2.46 0.289 2 11.469 0.174 3 2 2.46
DI 3E 0.59 0.6 5 7.51 2.685 0.02 0.05 2.685 0.304 2 12.189 0.164 3 2 2.685
DI 3S 0.38 0.6 5 7.51 1.714 0.02 0.05 1.714 0.238 2 8.907 0.225 3 2 1.714
SLAB TYPE CB 6J 0.64 0.6 5 7.51 2.928 0.02 0.05 2.928 0.348 2 14.398 0.139 2 2 2.928
DI 6K 0.45 0.6 5 7.51 2.031 0.02 0.05 2.031 0.261 2 10.035 0.199 3 2 2.031
DI 6L 0.34 0.6 5 7.51 1.557 0.02 0.05 1.557 0.227 2 8.325 0.24 3 2 1.557
DI 6H 0.52 0.6 5 7.51 2.342 0.02 0.05 2.342 0.282 2 11.084 0.18 3 2 2.342
DI 61 0.52 0.45 5 7.51 1.783 0.02 0.05 1.783 0.243 2 9.161 0.218 3 2 1.783
19

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
INLET SPREAD
CALCULATIONS
Note:
Inlet spread was calculated and measurements were taken to ensure the spread did not top
the crown of the road on local streets, at least one half of the travel lane in each direction is
free of water on the collector roads, and the velocities do not exceed 8 fps.
20

Name Drain. Runoff Tc Rainfall Q=CIA/Kc Long. Cross Cross Prey. Total Depth d Gutter Spread W/T Inlet Type Grate Grate Curb Curb Intercept Bypass Bypass
Area A Coeff. C Intens. Slope Slope Sx Slope Bypass Gutter Width T Length Width Opening Opening Flow Qi Flow Structure
SL Sw Flow Flow Length Height Qb
(acres) (min) (inch/hr) (cfs) (cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (ft) (ft) (cfs) (cfs)
CB 1F 0.18 0.85 5 4 0.63 -1.00 0.02 0.05 0.13 0.76 0.10 2.00 2.00 1.00 Combination 3.00 2.00 3.00 0.33 0.76 0.00 ---
CB 2F 0.49 0.6 5 _ 4 1.18 _ -1.00 0.02 _ 0.05 0.00 1.18 0.11 _ 2.00 _ 2.69 _ 0.74 Combination_ 2.00 _ 2.00 4.00 0.33 _ 1.18 0.00 --- _
CB 7D 0.14 0.6 5 4 0.33 0.03 0.02 0.05 0.00 0.33 0.10 2.00 1.98 1.01 Combination 3.00 2.00 4.00 0.33 0.00 0.33 CB 7B
CB 7C 0.33 0.6 5 4 0.80 -1.00 0.02 0.05 0.31 1.10 0.16 2.00 5.13 0.39 Combination 2.00 2.00 4.00 0.33 1.10 0.00 ---
CB 7P 0.28 0.6 5 4 0.67 0.03 0.02 0.05 0.20 0.88 0.14 2.00 3.94 0.51 Combination 3.00 2.00 3.00 0.33 0.81 0.06 CB 7F
CB 7M 0.04 0.6 5 4 0.10 0.03 0.02 0.05 0.08 0.18 0.08 2.00 1.57 1.28 Combination 3.00 2.00 3.00 0.33 0.18 0.00 CB 71
DBL CB 2B 0.63 0.6 5 4 1.53 0.02 0.02 0.05 0.00 1.53 0.19 2.00 6.16 0.33 Combination 6.00 2.00 6.00 0.33 1.33 0.21 ---
CB 3B 0.52 0.6 5 4 1.27 0.02 0.02 0.05 0.00 1.27 0.18 2.00 5.85 0.34 Combination 3.00 2.00 3.00 0.33 1.02 0.25 CB 3A
CB 7R 0.52 0.6 5 _ 4 1.26 _ 0.01 0.02 _ 0.05 0.00 1.26 0.18 _ 2.00 _ 5.90 _ 0.34 Combination_ 3.00 _ 2.00 3.00 0.33 _ 1.01 0.25 CB 7N
CB 7F 0.53 0.6 5 4 1.29 0.04 0.02 0.05 0.06 1.36 0.16 2.00 4.75 0.42 Combination 3.00 2.00 4.00 0.33 1.23 0.13 ---
CB 7B 0.05 0.7 5 4 0.13 0.03 0.02 0.05 0.33 0.47 0.11 2.00 2.59 0.77 Combination 3.00 2.00 3.00 0.33 0.46 0.00 CB 7C
CB 11 0.51 0.6 5 4 1.24 0.02 0.02 0.05 0.00 1.24 0.17 2.00 5.50 0.36 Combination 3.00 2.00 3.00 0.33 1.03 0.22 DCB 1C
CB 1H 0.55 0.6 5 4 1.33 0.02 0.02 0.05 0.00 1.33 0.18 2.00 5.67 0.35 Combination 3.00 2.00 3.00 0.33 1.08 0.25 CB 1G
CB 1G 0.16 0.4 5 4 0.27 0.02 0.02 0.05 0.25 0.51 0.13 2.00 3.39 0.59 Combination 3.00 2.00 4.00 0.33 0.51 0.00 CB 1F
DCB 1C 0.58 0.6 5 4 1.41 -1.00 0.02 0.05 0.22 1.63 0.20 2.00 6.75 0.30 Combination 2.00 2.00 4.00 0.33 1.63 0.00 ---
DBL CB 1N 0.79 0.6 5 _ 4 1.92 _ -1.00 0.02 _ 0.05 0.00 1.92 0.13 _ 2.00 _ 3.29 _ 0.61 Combination _ 6.00 _ 2.00 6.00 0.33 _ 1.92 0.00
CB 5H 0.69 0.5 5 4 1.38 0.04 0.02 0.05 0.00 1.38 0.16 2.00 4.91 0.41 Combination 3.00 2.00 3.00 0.33 1.18 0.20 CB 5B
CB 5L 0.22 0.6 5 4 0.53 0.04 0.02 0.05 0.00 0.53 0.12 2.00 2.70 0.74 Combination 3.00 2.00 3.00 0.33 0.52 0.00 CB 5K
CB 5K 0.21 0.6 5 4 0.52 0.04 0.02 0.05 0.00 0.52 0.11 2.00 2.72 0.74 Combination 3.00 2.00 3.00 0.33 0.52 0.00 CB 5C
CB 50 0.50 0.5 5 4 1.02 -1.00 0.02 0.05 0.00 1.02 0.18 2.00 6.15 0.33 Combination 3.00 2.00 3.00 0.33 1.02 0.00 ---
CB 5M 0.13 0.7 5 4 0.35 0.04 0.02 0.05 0.00 0.35 0.10 3.00 1.98 1.52 Combination 3.00 2.00 3.00 0.33 0.35 0.00 CB 5L
CB 4C 0.22 0.7 5 4 0.63 0.01 0.02 0.05 0.00 0.63 0.15 2.00 4.57 0.44 Combination 3.00 2.00 3.00 0.33 0.57 0.06 CB 4A
CB 4B 0.58 0.6 5 _ 4 1.41 _ 0.01 0.02 _ 0.05 0.00 1.41 0.20 _ 2.00 _ 6.74 _ 0.30 Combination_ 3.00 _ 2.00 3.00 0.33 _ 1.08 0.33 CB 4E
CB 4D 0.05 0.7 5 4 0.15 0.01 0.02 0.05 0.01 0.16 0.09 2.00 1.88 1.06 Combination 3.00 2.00 4.00 0.33 0.00 0.16 CB 3T
CB 3T 0.12 0.7 5 4 0.33 -1.00 0.02 0.05 0.16 0.49 0.10 2.00 2.00 1.00 Combination 3.00 2.00 3.00 0.33 0.49 0.00 ---
CB 3D 0.48 0.6 5 4 1.17 0.01 0.02 0.05 0.00 1.17 0.18 2.00 5.85 0.34 Combination 2.00 2.00 4.00 0.33 1.07 0.10 ---
CB 3N 0.40 0.6 5 4 0.97 -1.00 0.02 0.05 0.23 1.21 0.12 2.00 2.74 0.73 Combination 3.00 2.00 3.00 0.33 1.21 0.00 ---
CB Si 0.25 0.6 5 4 0.61 0.02 0.02 0.05 0.00 0.61 0.14 2.00 3.75 0.53 Combination 2.00 2.00 4.00 0.33 0.60 0.01 ---
CB 3R 0.19 0.6 5 4 0.47 -1.00 0.02 0.05 0.00 0.47 0.10 2.00 2.00 1.00 Combination 2.00 2.00 4.00 0.33 0.47 0.00 ---
CB 3M 0.10 0.7 5 _ 4 0.29 _ 0.02 0.02 _ 0.05 0.00 0.29 0.10 _ 2.00 _ 2.16 _ 0.93 Combination_ 2.00 _ 2.00 4.00 0.33 _ 0.29 0.00 CB 3T
DCB 3H 0.71 0.7 5 4 2.00 -1.00 0.02 0.05 0.00 2.00 0.16 2.00 5.19 0.39 Combination 2.00 2.00 4.00 0.33 2.00 0.00 ---
DCB 3J 0.18 0.6 5 4 0.44 -1.00 0.02 0.05 0.00 0.44 0.10 2.00 2.00 1.00 Combination 2.00 2.00 4.00 0.33 0.44 0.00 ---
CB 6F 0.24 0.6 5 4 0.58 0.04 0.02 0.05 0.00 0.58 0.12 2.00 2.86 0.70 Combination 3.00 2.00 3.00 0.33 0.57 0.01 DBL CB 6C
CB 6E 0.36 0.6 5 4 0.87 0.04 0.02 0.05 0.00 0.87 0.14 2.00 3.72 0.54 Combination 3.00 2.00 3.00 0.33 0.82 0.05 DBL CB 6D
DBL CB 6D 0.62 0.6 5 4 1.51 -1.00 0.02 0.05 0.22 1.73 0.15 2.00 4.42 0.45 Combination 2.00 2.00 4.00 0.33 1.73 0.00 ---
DBL CB 6C 0.47 0.6 5 4 1.14 -1.00 0.02 0.05 0.01 1.14 0.11 2.00 2.58 0.78 Combination 2.00 2.00 4.00 0.33 1.14 0.00 ---
21

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
HW/D
CALCULATIONS
22

CHARLO 1TE-M ECKLENBURG STO RVI WATER DESIG NM ANUAL
FES 8B
7180 - 10,000
- 168 - 8,000 EXAMPLE (I) (2) (3)
- 156 - 6,000 0.42 Inches (3.5 foot) - 6,
- 6,
- 5,000 0.120 ifs - 6.
- 144 - - 6, - - 5.
- 132 - 4,000 ± +► t ilt Nw - -- 4.
- 3,000 (I) 2.3 ewe - 5. _ - 4.
- 120 - -
- (2) 2.I 7.4 - -
- 2,000 (3) 2.2 7.7 4, -
-
- 108 - - - 3. -
- ' In f..t - - -3.0
- 96 - 1,000 - 3. - _
- 800 - _ -
- 84 - 600 ��- 2 - 2-
` - 500 - -
- 72 - 400 // e - 2. - -
_ - �yj 3 - - 1.6
w - 300 F - 1.5
o N = / °f- -
z - 60 v - 200 W 1.5
z - - w _ -
c - 5a ar/ es _ - -
er �w - 100 Z
J - 48 - 80 I -
Q -
c=i / I - 60 a - 1.0 - 1.0
42 w
u.o 1/1
- 50 HW SCALE ENTRANCE -I.0 - -
- 40 p TYPE 0C
ar _ _
HW 8B Ilti 6 - 30 (I) Square •�• _ - .9
w
Q - 33 _ headwallQ -
-s• . (2) Groote d with
HW 8B EQUIV. • - °dwell i - .8 ^ .8
BURIED 6" = 13) Groove end - •8
- 27 - ro)ecting -
10
- 8 " 'T .7-
- 24 .
6 To use scale(2)or(3)project -
21 5 hurl:ontony to scale (I),then -
4-
use straight inclined line through
0 and 0 scales,or reverse os - .6
3 illustrated. - .6 - .6
FES 3G - 16
- 2 - - -
BUREAU OF PUBLIC ROA0S JAN.19e3
- 15
.5 - .5
- 1.0 HEADWATER SCALES 2 d3 - •5
REVISED MAY 1964
- 12
Figure 5C-5 Headwater Depth for Concrete Pipe Culverts with Inlet Control
Source:www.deldot.gov/inform lion/pubs_form s'm aivals/road_design/pdf/supp_figures_chap6.pdf
Q 25 YEAR
1) HW 8B = 21.30 CFS
2) FES 3G = 6.01 CFS
5-32
23

MCBRIDE SUBDIVISION
HEMS Y BRIDGE, NORTH CAROLINA
FES & RIP RAP
CALCULATIONS
Narrative: Flows values for sizing of rip rap aprons into ponds and Idlewilde Road culvert
extension are the 25-yr storm events and can be obtained from the preceeding calcs titled
"25-yr Event Storm Capacity Calculations". Flow values for sizing of the rip rap apons out
of BMPs #1 and #2 are the 10-yr storm events and can be obtained from the following
HydroCAD output data.
24

3D°
Outlet - If ' Do + 0.4La 120 — •; ::
pipe i: t. : i I :'t•
diameter(Do),. La 110 :.' ...- ; .. 'i. .,!.I .r,.IIi ri I. :; ,I I.
5D • -i� i i'' •. ' i 11 i irj r 1¢�
- - - ° 100 , , . I.i'' ' - ' . f�Il iiii + . 11; ' 1
. II IiI;II iia'Ii •
i . i 11 111111111 I
n■MIM
90 1.1. 1 '!' 1 11111
11 —.1 'I ■RNLI
uv. a lam
r pp IIH11111 1 r I 1
I I.i I •1' 1 I r 1111r1 II II
i �I i ,'Rp I I I III 71gii�liom, ii ii -,o; I.
� 80 .t. 1 III,: . !1MVjJj0 � OW•,r' l i:: r _i u A A In
1 -I 1
Q 70 "/HI y - - 1 O 1 I II is
p� E r.�: 1 II 10 1O 60 ■1�i um ' ' II , � , IF
1 IJ� -•� :r + 'I, ``V v 7'i' ; . . . i w11� l 64 I �. 1■{I• 5D „�� •A ,in =■ I II II 1 I N1 II III
`i. Ibiii
l�.. ■ .I, .. . r1 r r 'II r Ila1 �i- - r•, - r 1 II ■_ om C I I,. r.• ..6 , , k1 � P '111I' •:,D I , r , , r rl ti� 1 I1�I 1 III
' I' r' I his i '
30 liimis 'i' ill �'i"• I 'Al1 , �II �' 1� t �', 1, ;r. t t'}
duIr11./ T Pi1, iirl I IJ r _ I r :,�'-' I.' "� ��,ii
•.1={I1iir-: = ,�i 'r l IN IF "ru®i�:� �� i'' ii{
20 I.1 ■. ■e r 1 d I liiruii rI 1 i,.i . . . r. V'c� `r '. I { r ruorh`,. 2 N
-----_ !ll :"ri FAii2i�ril�iiili' _:�l!lllill!! i llllr ,• 1::.; I -:- • _I'lp n
1/' 'I N • 'i i r �/ r r A • OJT � l cts
» . '^ ''i .+'`.. NIB 1. 'rl :II 11 ,v 9 of A y od��llili -il 1 Q
CC
°ta
2 v=1s. rr i=r rlllu s
ri '!1"
Tr:
1-,'- ' I 1,!I 6 �.- it - it j�jj/ . . .I...I
. Imo II t I : . .1 ..:il ! I.;.. III.: E!;. Ili illlL,',rUO
3 5 +10 ?0 •`1 100 200 500 1000
Discha . e(ff3/s-c)
Maximum Tai water Conditions
d (in.) Q(cfs) Description of Apron
1 FES 1A 48 79.94 » 18'L x 12'W x 18"D CLASS B APRON
2 FES 2 48 67.64 » 18'L x 12'W x 18"D CLASS B APRON
3 FES 6A 36 22.15 » 14'L x 10'W x 18"D CLASS B APRON
4 HW 8A 36 21.30 » 14'L x 10'W x 18"D CLASS B APRON
4 FES RD1 18 13.78 » 14'L x 10'W x 18"D CLASS B APRON
5 BMP OS1 2X24" 52.72 » 14'L x 10'W x 18"D CLASS B APRON
6 BMP 0S2 36" 4.32 » 14'L x 10'W x 18"D CLASS B APRON
P:\Active Projects\DRB Group\Hemby Bridge Development,0155\Engineering\Calculations\Storm Design\Storm\20155-
FE xls

THE ISAACS GROUP
RIP RAP APRON DESIGN
McBride Subdivision
Hemby Bridge, North Carolina
Maximum Tailwater Conditions
D = OUTLET PIPE DIAMETER (in)
Do =OUTLET PIPE DIAMETER (ft)
La= LENGTH OF APRON (ft) [FROM FIGURE 8-2,CHARLOTTE STORMWATER DESIGN MANUAL](MINIMUM La=10
W =WIDTH OF APRON (ft) [w=Do+0.4 La]
Q = FLOW (cfs)
d50 = STONE SIZE (ft) [FROM FIGURE 8-2,CHARLOTTE STORMWATER DESIGN MANUAL]
FES 1A FES 2 FES 6A FES 8A FES-RD1 BMP BMP
OS1 OS2
D 48 48 36 30 18 34 36
Q 79.94 67.64 22.15 21.30 13.78 52.72 4.32
Do 4 4 3 2.5 1.5 2.83333 3
3D, 12 12 9 7.5 4.5 8.5 9
La 18 18 14 14 14 14 14
W 11.2 11.2 8.6 8.1 7.1 8.43333 8.6
d50 0.5 0.5 0.5 0.5 0.5 0.5 0.5
*MIN.APRON SIZE NOT TO BE LESS THAN 8'Wx11'Lx18"D CLASS B APRON
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\Storm Design\Storm\20155-
FEg.xls

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
SWALE CALCULATIONS
North American Green Erosion Control Materials Design Software was used to determine the
following:
• The normal depth of the swale under poorly maintained grass depth conditions (Class B).
• The vegetation stability when the grass is properly maintained by a homeowner (Class D).
• The temporary liner stability before the swale is stabilized with vegetation.
The drainage areas and swale slopes were determined from the construction drawings. The
retardance class was set to D (grass depth 2-6 inches) in the NAG software for a properly
maintained grass swale to determine vegetation stability. Next, to determine the depth of swale
with 6" of freeboard, the retardance class is set to B (grass depth 12-24 inches) for an under or
no maintained grass. Finally, the swale was modeled as unvegetated with a S75 temporary liner
to determine liner and dirt stability before grass has been established. Swales that were unstable
for any reason either were widened and/or lined with different temporary liners until stabilization
or freeboard requirements were achieved. If the calculations of the temporary linear showed a
velocity of less than 2 fps during a 10-year storm event then the temporary linear was removed.
Swale Type A is the typical swale in the backyards of the lots. The design of this swale was
made using the largest drainage area for all rear yard inlets, which is 1 .75 acres to Slab Type CB
3K.
Next, we looked for rear yard swales that were in excess of 2.0% and analyzed these swales.
• Swale Al @ 5.89% on lots 6-7
• Swale A2 @ 5.0% on lot 33
Swale Type B receives flows from larger drainage areas than the type A swale. There are 4
Type B swales in the project. The design of this swale was made using the largest contributing
flow of 15.06 cfs for a swale at 1.5% and at 2.0%
27

12/17/23,2:25 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale Al
Name Swale Al
Discharge 2.22
Channel Slope 0.0589 " ^'^' '
Channel Bottom Width 1
Left Side Slope 3 i ,
Right Side Slope 3 �\
Low Flow Liner w
.'Retardence Class B 12-24 in
Vegetation Type Bunch Type 'I -• 0
s S.
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 2.22 cfs 1.66 ft/s 0.52 ft 0.1 4 lbs/ft2 1.92 lbs/ft2 2.09 STABLE
Vegetation
Underlying Straight 2.22 cfs 1.66 ft/s 0.52 ft 0.1 4 lbs/ft2 1.14 lbs/ft2 3.5 STABLE --
Substrate
28
https://ecmds.com/project/158999/channel-analysis/256551/show 1/1

12/17/23,2:25 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale Al
Name Swale Al
Discharge 2.22 flow ut«„.1
Channel Slope 0.0589
Channel Bottom Width 1 i
Left Side Slope 3 \ \
Right Side Slope 3
Low Flow Liner '!
Retardence Class D 2-6 in '1._. 1,. �'
Vegetation Type Bunch Type S.
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 2.22 cfs 4 ft/s 0.29 ft 0.03 4 lbs/ft2 1.07 lbs/ft2 3.74 STABLE
Vegetation
Underlying Straight 2.22 cfs 4 ft/s 0.29 ft 0.03 0.98 Ibs/ft2 0.71 lbs/ft2 1.4 STABLE --
Substrate
29
https://ecmds.com/project/158999/channel-analysis/256551/show 1/1

12/17/23,2:26 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale Al
Name Swale Al
Discharge 2.22
Channel Slope 0.0589
Channel Bottom Width 1 l
•
Left Side Slope 3 _ 9\
Right Side Slope 3
Low Flow Liner '�
U •
Retardence Class E<2 in _ s.
Vegetation Type None
Vegetation Density None
Soil Type Clay(GC)
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
DS75 Straight 2.22 cfs 4 ft/s 0.29 ft 0.03 1.6 Ibs/ft2 1.07 lbs/ft2 1.5 STABLE D
Unvegetated
Underlying Straight 2.22 cfs 4 ft/s 0.29 ft 0.03 1.97 Ibs/ft2 0.71 lbs/ft2 2.8 STABLE D
Substrate
30
https://ecmds.com/project/158999/channel-analysis/256551/show 1/1

12/17/23,2:23 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALE A2
Name SWALE A2
Discharge 2.65
Channel Slope 0.05 •
Channel Bottom Width 1
Left Side Slope 3 M
9
Right Side Slope 3
Low Flow Liner a
Retardence Class B 12-24 in - 114`,�
Vegetation Type Bunch Type
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 2.65 cfs 8.8 ft/s 0.19 ft 0.01 4 lbs/ft2 0.6 lbs/ft2 6.7 STABLE
Vegetation
Underlying Straight 2.65 cfs 8.8 ft/s 0.19 ft 0.01 0.11 Ibs/ft2 0.43 lbs/ft2 0.26 UNSTABLE --
Substrate
31
https://ecmds.com/project/158999/channel-analysis/256552/show 1/1

12/17/23,2:10 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALE A2
Name SWALE A2
Discharge 5.16
Channel Slope 0.05 ;
Channel Bottom Width 1
Left Side Slope 3
Right Side Slope 3 _ , �\
Low Flow Liner "_• ': V "
Retardence Class D 2-6 in -- Si i,
Vegetation Type Bunch Type s `-s'
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
Underlying Straight 5.16 cfs 4.73 ft/s 0.46 ft 0.03 0.98 Ibs/ft2 0.87 lbs/ft2 1.13 STABLE
Substrate
Unreinforced Straight 5.16 cfs 4.73 ft/s 0.46 ft 0.03 4 lbs/ft2 1.43 lbs/ft2 2.8 STABLE --
Vegetation
32
https://ecmds.com/project/158999/channel-analysis/256552/show 1/1

12/17/23,2:24 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALE A2
Name SWALE A2
Discharge 2.65
Channel Slope 0.05
Channel Bottom Width 1
Left Side Slope 3
Right Side Slope 3
Low Flow Liner v -
Retardence Class E<2 in
Vegetation Type None s. • y
Vegetation Density None
Soil Type Clay(GC)
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Remarks
Depth Mannings N Shear Stress Shear Stress Factor Pattern
DS75 Straight 2.65 cfs 3.97 ft/s 0.33 ft 0.03 1.6 Ibs/ft2 1.04 lbs/ft2 1.54 STABLE D
Unvegetated
Underlying Straight 2.65 cfs 3.97 ft/s 0.33 ft 0.03 1.97 Ibs/ft2 0.67 Ibs/ft2 2.95 STABLE D
Substrate
33
https://ecmds.com/project/158999/channel-analysis/256552/show 1/1

12/18/23, 1:53 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale 2B
Name Swale 26
Discharge 15.06
Channel Slope 0.02
Channel Bottom Width 4
Left Side Slope 3
Right Side Slope 3 `fir\
Low Flow Liner ; —. _
Retardence Class B 12-24 in ,5 i L, I. ,.
Vegetation Type Bunch Type s s. j
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 15.06 cfs 1.75 ft/s 1.15 ft 0.1 4 lbs/ft2 1.44 Ibs/ft2 2.78 STABLE --
Vegetation
Underlying Straight 15.06 cfs 1.75 ft/s 1.15 ft 0.1 4 lbs/ft2 0.95 lbs/ft2 4.21 STABLE
Substrate
34
https://ecmds.com/project/158999/channel-analysis/256588/show 1/1

12/18/23, 1:52 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale 2B
Name Swale 2B
Discharge 15.06
Channel Slope 0.02 rw..w«„ ,
Channel Bottom Width 4
Left Side Slope 3
Right Side Slope 3 \ \
Low Flow Liner
Retardence Class D 2-6 in •
. awe
Vegetation Type Bunch Type Tel"' '
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 15.06 cfs 4.16 ft/s 0.62 ft 0.03 0.98 lbs/ft2 0.57 lbs/ft2 1.72 STABLE
Substrate
Unreinforced Straight 15.06 cfs 4.16 ft/s 0.62 ft 0.03 4 Ibs/ft2 0.77 Ibs/ft2 5.19 STABLE
Vegetation
35
https://ecmds.com/project/158999/channel-analysis/256588/show 1/1

12/18/23, 1:54 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>Swale 2B
Name Swale 2B
Discharge 15.06
Channel Slope 0.02
Channel Bottom Width 4
Left Side Slope 3
Right Side Slope 3 • 9
Low Flow Liner
Retardence Class E<2 in 11111 1 11111
D
Vegetation Type None
Vegetation Density None
Soil Type Clay(GC)
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
DS75 Straight 15.06 cfs 4.16 ft/s 0.62 ft 0.03 1.6 lbs/ft2 0.77 lbs/ft2 2.07 STABLE D
Unvegetated
Underlying Straight 15.06 cfs 4.16 ft/s 0.62 ft 0.03 1.97 lbs/ft2 0.57 lbs/ft2 3.45 STABLE D
Substrate
36
https://ecmds.com/project/158999/channel-analysis/256588/show 1/1

12/18/23, 1:57 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALEB
Name SWALE B
Discharge 15.06
Channel Slope 0.015
Channel Bottom Width 4
Left Side Slope 3 ,
Right Side Slope 3 s\
Low Flow Liner
Retardence Class B 12-24 in
Vegetation Type Bunch Type _ 4_41iic.,.: ~
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 15.06 cfs 1.58 ft/s 1.24 ft 0.1 4 Ibs/ft2 1.16 lbs/ft2 3.45 STABLE --
Vegetation
Underlying Straight 15.06 cfs 1.58 ft/s 1.24 ft 0.1 4 lbs/ft2 0.76 lbs/ft2 5.3 STABLE
Substrate
37
https://ecmds.com/project/158999/channel-analysis/256589/show 1/1

12/18/23, 1:56 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALEB
Name SWALE B
Discharge 15.06
Channel Slope 0.015
Channel Bottom Width 4
Left Side Slope 3
Right Side Slope 3
9
Low Flow Liner
Retardence Class D 2-6 in
Vegetation Type Bunch Type
Vegetation Density Good 65-79%
Soil Type Clay(GC)
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 15.06 cfs 3.76 ft/s 0.67 ft 0.03 0.98 lbs/ft2 0.46 lbs/ft2 2.16 STABLE
Substrate
Unreinforced Straight 15.06 cfs 3.76 ft/s 0.67 ft 0.03 4 Ibs/ft2 0.62 Ibs/ft2 6.41 STABLE
Vegetation
38
https://ecmds.com/project/158999/channel-analysis/256589/show 1/1

12/18/23, 1:57 PM ECMDS 7.0
NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>SWALEB
Name SWALE B
Discharge 15.06 low U""'°"
Channel Slope 0.015
Channel Bottom Width 4
Left Side Slope 3
Right Side Slope 3
r
Low Flow Liner
Retardence Class E<2 in D
s.
Vegetation Type None
Vegetation Density None
Soil Type Clay(GC)
DS75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
DS75 Straight 15.06 cfs 3.76 ft/s 0.67 ft 0.03 1.6 lbs/ft2 0.62 lbs/ft2 2.56 STABLE D
Unvegetated
Underlying Straight 15.06 cfs 3.76 ft/s 0.67 ft 0.03 1.97 lbs/ft2 0.46 lbs/ft2 4.33 STABLE D
Substrate
39
https://ecmds.com/project/158999/channel-analysis/256589/show 1/1

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
EROSION CONTROL CALCULATIONS
Narrative:
Erosion control measures have been designed in accordance with North Carolina
Department of Environment & Natural Resource requirements and standards. Erosion
control is maintained on the site via silt fence, diversion ditches, storm drainage inlet
protection and riser and skimmer basins. The sediment pond and skimmer have been
sized for the 10 year storm event.
40

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
Riser & Skimmer Sediment
Basins Calculations
41

RISER BASIN #1
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Riser Basin Design&Calculations(BASIN#1)
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 3-3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed)(Phase 1) 773,556 (sq.ft.) 17.76 ac
Ad,Drainage Area to Structure(Mid-Developed)(Phase 2) 1,437,374 (sq.ft.) 33.00 ac
Ad,Drainage Area to Structure(Post-Developed)(Phase 3) 1,773,655 (sq.ft.) 40.72 ac
Drainage Area to Structure 40.72 (ac.)
Area of disturbance for structure 40.72 (ac.)
Q1o,Peak Flow=CiA 147.805 (cfs)
Basin Design#1
Volume Calculation
Bottom of Basin Elevation= 633.80
Depth of Basin(to principal spillway) 2.70 (ft.)
Riser Orifice Elevation= 636.50 Diff.b/t Riser Orif.and Emer.Spillwe 3.33 ft.
Emergency Spillway Elev.= 639.83
Top of Dam Elevation = 641.33
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
633.80 55,981 1.285 - -
635.00 60,211 1.382 69,715 69,715
636.00 64,479 1.480 62,345 132,060
636.50 68,803 1.579 33,321 165,381
637.00 73,185 1.680 35,497 200,878
639.50 84,384 1.937 196,961 397,839
641.00 91,274 2.095 131,744 529,582
Basin Volume Required(1800cu.ft./disturbed ac.)= 73,292 (cu.ft.)
Basin Volume Provided at Riser Crest= 165,381 (cu.ft.) Greater than required,therefore OK
Required Basin Surface Area(Q1ocfsx435 sf)= 64,295 (sq.ft.)
As,Surface Area Provided= 68,803 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
42

Principal Spillway Riser Barrel Design:
i,2 yr.Rainfall Intensity(table 3-3) 2.22 (in./hr.)
Q2,Peak Flow=CiA= 45.20 (cfs)
Weir Length @ 638.00= 648 (in.)
Proposed Barrel Length(5.0'increments)= 55.0 (ft.)
Proposed Riser Diameter= 100 (in.)
Analyze Weir,Orifice and Barrel flow for limiting(controling)flow in principal spillway
Weir flow Q=CLH^1.5 1017.24 cfs
C=3.1,H=Height b/t riser and emer.Spillway
L=Weir length
Orifice floes Q=CA(2gH)^0.5 478.99 cfs
C=0.6
H= height b/t riser and emergency spillway _
Pipe flow QP=(a'I2gH)/'J(1+Km+KPL) 31650.76 cfs
Km= 1
Kp= 0.0006 from table 8.07a
H= depth from bottom basin to emergency spillway
Minimum principal spillway flow= 478.99 Greater than Q2,therefore OK
Emergency Spillway Calculation:
Q,o= 147.805 (cfs)
QP= 478.987 (cfs)
Qe=Qio-QP= -331.182 (cfs)
Spillway Width= 30.0 (ft.) Spillway Elev.= 638
h= #NUM! (ft.) #NUM! Riser flow exceeds Q10 before reaching emergency spillway
Concrete Anchor Buoyancy Calculation
Riser Height(h)= 5.00 (ft.) crest el.to 48"inv.out
Riser Outside Length(I)= 10.00 (ft.)
Riser Outside Width(w)= 7.00 (ft.)
Riser Wall Thickness(t)= 0.50 (ft.)
Vol.of riser(VR)= 350.0 (ft3) VR =1 x w x h
Wt.of H2O displaced(WR)= 21840.0 (Ibs) WR =62.4 lbs/ft3 x VR
Conc.pad thickness= 30 (in.)
Conc.pad width/length= 9.67 (ft.)
Vol.of conc.pad(Vc)= 233.77 (ft3)
Wt.of H2O displaced(Wc)= 14587.39 (Ibs) Wc =62.4 lbs/ft3 x Vc
Tot.Wt.of H2O displaced(WD)= 36427.4 (Ibs) WD=WR+Wc
Unit wt.of concrete = 150 (Ibs/ft3)
Wt.of conc.pad = 35065.84 (Ibs)
Riser Outside Area(Ao)= 70 (ft2)
Riser Inside Area(Ai)= 54 (ft2)
Wt.of Riser Structure= 12000 (Ibs)
Factor of safety= wt.Conc.Pad+wt.Riser Structure
wt.of H2O displaced
F.S.= 1.29 OK
ANTI-FLOTATION DEVICE
SIZED WITH PERM. BMP #1
OUTLET STRUCTURE SEE C4.8
43

RISER BASIN #2
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Riser Basin Design&Calculations(BASIN#2)
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 3-3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed)(Phase 1) 322,259 (sq.ft.) 7.40 ac
Ad,Drainage Area to Structure(Mid-Developed)(Phase 2) 290,477 (sq.ft.) 6.67 ac
Ad,Drainage Area to Structure(Post-Developed)(Phase 3) 285,494 (sq.ft.) 6.55 ac
Drainage Area to Structure 7.40 (ac.)
Area of disturbance for structure 7.40 (ac.)
Qui,Peak Flow=CiA 26.855 (cfs)
Basin Design#1
Volume Calculation
Bottom of Basin Elevation= 636.00
Depth of Basin(to principal spillway) 3.50 (ft.)
Riser Orifice Elevation= 639.50 Diff.b/t Riser Orif.and Emer.Spillwe 1.00 ft.
Emergency Spillway Elev.= 640.50
Top of Dam Elevation = 642.00
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
636.00 480 0.011 - -
637.00 8,745 0.201 4,613 4,613
638.00 10,016 0.230 9,381 13,993
639.50 12,028 0.276 16,533 30,526
640.00 12,728 0.292 6,189 36,715
641.00 14,168 0.325 13,448 50,163
642.00 15,666 0.360 14,917 65,080
Basin Volume Required(1800cu.ft./disturbed ac.)= 13,316 (cu.ft.)
Basin Volume Provided at Riser Crest= 30,526 (cu.ft.) Greater than required,therefore OK
Required Basin Surface Area(Owcfsx435 sf)= 11,682 (sq.ft.)
As,Surface Area Provided= 12,028 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
44

RISER BASIN #2
Principal Spillway Riser Barrel Design:
i,2 yr.Rainfall Intensity(table 3-3) 2.22 (in./hr.)
Q2,Peak Flow=CiA= 8.21 (cfs)
Proposed Barrel!Dia.= 36 (in.)
Proposed Barrel Length(5.0'increments)= 65.0 (ft.)
Proposed Riser Diameter= 100 (in.)
Analyze Weir,Orifice and Barrel flow for limiting(controling)flow in principal spillway
Weir flow Q=CLH^1.5 cfs
C=3.1,H=Height b/t riser and emer.Spillway
L=Weir length
Orifice floes Q=CA(2gH)^0.5 262.48 cfs
C=0.6
H= height b/t riser and emergency spillway
Pipe flow QP=(a'I2gH)/'J(1+Km+KPL) 62.20 ■cfs
Km= 1
Kp= 0.0267 from table 8.07a
H= depth from bottom basin to emergency spillway
Minimum principal spillway flow= 62.20 Greater than Q2,therefore OK
Emergency Spillway Calculation:
Q,o= 26.855 (cfs)
QP= 62.203 (cfs)
Qe=Qio-QP= -35.348 (cfs)
Spillway Width= 20.0 (ft.) Spillway Elev.= 640.5
h= #NUM! (ft.) #NUM! Riser flow exceeds Q10 before reaching emergency spillway
Concrete Anchor Buoyancy Calculation
Riser Height(h)= 9.00 (ft.) crest el.to 48"inv.out
Riser Outside Length(I)= 5.00 (ft.)
Riser Outside Width(w)= 5.00 (ft.)
Riser Wall Thickness(t)= 0.50 (ft.)
Vol.of riser(VR)= 225.0 (ft3) VR =1 x w x h
Wt.of H2O displaced(WR)= 14040.0 (Ibs) WR =62.4 lbs/ft3 x VR
Conc.pad thickness= 24 (in.)
Conc.pad width/length= 9.67 (ft.)
Vol.of conc.pad(Vc)= 187.02 (ft3)
Wt.of H2O displaced(Wc)= 11669.91 (Ibs) Wc =62.4 lbs/ft3 x Vc
Tot.Wt.of H2O displaced(WD)= 25709.9 (Ibs) WD=WR+We
Unit wt.of concrete = 150 (Ibs/ft3)
Wt.of conc.pad = 28052.67 (Ibs)
Riser Outside Area(Ao)= 25 (ft2)
Riser Inside Area(Ai)= 16 (ft2)
Wt.of Riser Structure= 12150 (Ibs)
Factor of safety= wt.Conc.Pad+wt.Riser Structure
wt.of H2O displaced
F.S.= 1.56 OK
45

SKIMMER BASIN #3
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Riser Basin Design&Calculations(BASIN#3)
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 3-3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed) 630,152 (sq.ft.) 14.47 ac
Ad,Drainage Area to Structure(Post-Developed) 216,166 (sq.ft.) 4.96 ac
Drainage Area to Structure 14.466 (ac.)
Area of disturbance for structure 14.466 (ac.)
Q70,Peak Flow=CiA 52.513 (cfs)
Basin Design#1
Volume Calculation
Bottom of Basin Elevation= 646.00
Depth of Basin(to principal spillway) 3.50 (ft.)
Riser Inlet Elevation= 649.50 Diff.b/t Riser and Emer.Spillway= 1.00 ft.
Emergency Spillway Elev.= 650.50
Top of Dam Elevation = 652.00
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
646 2,300 0.053 - -
646.5 7,345 0.169 2,411 2,411
647 18,951 0.435 6,574 8,985
649.5 23,417 0.538 52,960 61,945
650.5 25,283 0.580 24,350 86,295
652 28,187 0.647 40,103 126,398
Basin Volume Required(1800cu.ft./disturbed ac.)= 26,039 (cu.ft.)
Basin Volume Provided at Riser Crest= 61,945 (cu.ft.) Greater than required,therefore OK
Required Basin Surface Area(Q10c5x435 sf)= 22,843 (sq.ft.)
As,Surface Area Provided= 23,417 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
46

SKIMMER BASIN #3
Principal Spillway Riser Barrel Design:
i,2 yr.Rainfall Intensity(table 3-3) 2.22 (in./hr.)
Q2,Peak Flow=CIA= 16.06 (cfs)
Proposed Barrel Dia.= 24 (in.)
Proposed Barrel Length(5.0'increments)= 55.0 (ft.)
Proposed Riser Diameter= 36 (in.)
Analyze Weir, Orifice and Barrel flow for limiting(controling)flow in principal sp 100
Weir flow Q=CLH^1.5 cfs
C=3.1,H=Height b/t riser and emer.Spillway
L=Circumference of Riser
Orifice floxn Q=CA(2gH)^0.5 34.02 cfs
C=0.6
H= height b/t riser and emergency spillway
Pipe flow Qp=(a'2gH)/'J(1+Km+K.,L) 25.13 cfs
Km= 1
Kp= 0.0459 from table 8.07a
H= depth from bottom basin to emergency spillway
Minimum principal spillway flow= 25.13 Greater than Q2,therefore OK
Emergency Spillway Calculation:
Q1o= 52.513 (cfs)
Qp= 25.126 (cfs)
Qe=Q1p-Qp= 27.387 (cfs)
Spillway Width= 28.0 (ft.) 638
h= 0.47 (ft.) Less than 0.5',Therefore OK
Concrete Anchor Buoyancy Calculation
Height of riser= 7.00
Height of riser= 3.50
Dia.of riser= 3
Vol.of riser= 24.7
Wt.of H2O displaced= 1,544
Conc.pad thickness(in)= 12
Conc.pad width/length(ft)= 6
Vol.of conc.pad(cf)= 36
Wt.of H2O displaced= 2246.4
Tot.Wt.of H2O displaced= 3,790
Unit wt.of concrete(pcf)= 150
Wt.of conc.pad(lb.)= 5400
Factor of safety= wt.Conc.Pad
wt.of H2O displaced
F.S.= 1.42 Greater than 1.2,therefore OK
47

SKIMMER BASIN #4
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Skimmer Basin Design&Calculations(BASIN#4)
Time of Concentration Calculation
Peak Flow Calculation
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 2.3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed) 191,169 (sq.ft.) 4.39(ac.)
Ad,Drainage Area to Structure(Post-Developed; 98,471 (sq.ft.) 2.26(ac.)
Drainage Area to Structure 4.389 (ac.)
Area of disturbance for structure 4.389 (ac.)
Q,o,Peak Flow=CiA 15.931 (cfs)
Skimmer Basin Design#2
Volume Calculation
Bottom of Basin Elevation= 647.50
Depth of Basin(to spillway) 3.00 (ft.)
Emergency Spillway Elev.= 650.50
Top of Dam Elevation = 652.00 Diff.b/t spillway and top dam=1.5 feet
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
647.50 1,110 0.025
648.50 3,640 0.084 2,375 2,375
650.00 4,886 0.112 6,395 8,770
650.50 2,554 1
651.00 5,788 0.133 2,780 14,103
652.00 6,746 0.155 6,267 20,370
Basin Volume Required(1800cu.ft./dist.ac)= 7,900 (cu.ft.)
Basin Volume Provided at Spillway= 11,324 (cu.ft.) Greater than required,therefore OK
Barrel Flow Qp=(a'2gH)/'J(1+Km+K,L) 0.00 (cfs)
Required Basin Surface Area(Q10x325 sq.ft.)= 5,177 (sq.ft.)
As,Surface Area Provided= 5,330 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
Emergency Spillway Calculation: Q=CLH^1.5 100
C= 2.8
Q1o= 15.931 (cfs)
Spillway Width= 18.0 (ft.)
h= 0.46 (ft.) <0.5',Therefore OK
48

SKIMMER BASIN #5
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Skimmer Basin Design&Calculations(BASIN#5)
Time of Concentration Calculation
Peak Flow Calculation
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 2.3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed) 209,214 (sq.ft.) 4.80(ac.)
Ad,Drainage Area to Structure(Post-Developed; 100,120 (sq.ft.) 2.30(ac.)
Drainage Area to Structure 4.803 (ac.)
Area of disturbance for structure 4.800 (ac.)
Q,o,Peak Flow=CiA 17.435 (cfs)
Skimmer Basin Design#2
Volume Calculation
Bottom of Basin Elevation= 655.50
Depth of Basin(to spillway) 3.00 (ft.)
Emergency Spillway Elev.= 658.50
Top of Dam Elevation = 660.00 Diff.b/t spillway and top dam=1.5 feet
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
655.50 1,420 0.033
656.50 4,269 0.098 2,845 2,845
657.50 5,124 0.118 4,697 7,541
658.50 6,
659.00 6,513 0.150 3,137 16,258
660.00 7,510 0.172 7,012 23,270
Basin Volume Required(1800cu.ft./dist.ac)= 8,640 (cu.ft.)
Basin Volume Provided at Spillway= 13,121 (cu.ft.) Greater than required,therefore OK
Barrel Flow Qp=(a'2gH)/'J(1+1<m+KpL) 0.00 (cfs)
Required Basin Surface Area(Q10x325 sq.ft.)= 5,666 (sq.ft.)
As,Surface Area Provided= 6,036 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
Emergency Spillway Calculation: Q=CLH^1.5 100
C= 2.8
Q1o= 17.435 (cfs)
Spillway Width= 20.0 (ft.)
h= 0.46 (ft.) <0.5',Therefore OK
49

SKIMMER BASIN #6
The ISAACS GROUP Date 2/9/2024
McBride Subdivion Hemby Bridge,North Carolina
Skimmer Basin Design&Calculations(BASIN#6)
Time of Concentration Calculation
Peak Flow Calculation
Total Time of Concentration,Tc 5.00 (min.)
i,10 yr.Rainfall Intensity(table 2.3) 7.26 (in./hr.)
C,Rainfall Runoff Coefficient 0.5
AD,Drainage Area to Structure(Pre-Developed) 242,226 (sq.ft.) 5.56(ac.)
Ad,Drainage Area to Structure(Post-Developed; 232,136 (sq.ft.) 5.33(ac.)
Drainage Area to Structure 5.561 (ac.)
Area of disturbance for structure 1.600 (ac.)
Q,o,Peak Flow=CiA 20.186 (cfs)
Skimmer Basin Design#2
Volume Calculation
Bottom of Basin Elevation= 655.50
Depth of Basin(to spillway) 3.00 (ft.)
Emergency Spillway Elev.= 658.50
Top of Dam Elevation = 660.00 Diff.b/t spillway and top dam=1.5 feet
Contour Area Area Volume Total
Elev. (sq.ft.) (ac.ft.) (cu.ft.) (cu.ft.)
666.00 1,178 0.027
667.00 5,445 0.125 3,312 3,312
668.50 15,237 0.350 6,735 18,620
669.50 23,538 0.540 19,388 38,007
Basin Volume Required(1800cu.ft./dist.ac)= 2,880 (cu.ft.)
Basin Volume Provided at Spillway= 11,885 (cu.ft.) Greater than required,therefore OK
Barrel Flow Qp=(a'2gH)/'J(1+Km+K,L) 0.00 (cfs)
Required Basin Surface Area(Q10x325 sq.ft.)= 6,560 (sq.ft.)
As,Surface Area Provided= 11,702 (sq.ft.) Greater than required,therefore OK
See following sheet for Skimmer Size Calculation from Fairclothskimmer.com
Emergency Spillway Calculation: Q=CLH^1.5 100
C= 2.8
Q1o= 20.186 (cfs)
Spillway Width= 22.0 (ft.)
h= 0.48 (ft.) <0.5',Therefore OK
50

McBride Subdivision
Faircloth Skimmer Sizing Calculation
Basin No. 1
Volume required = 73,292 cf
Volume provided = 165,381cf
1. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 73,292 Cu.Ft� Skimmer Size 6.0 Inch
Days to Drain* 2 Days rage I Orifice Radius 2.5 Inch[es]
Orifice Diameter 5.1 Inch[es]
l'In NC assume 3 days to drain
2. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 165.381 Cu.Ft Skimmer Size 6.0 Inch
Days to Drain* 5 Days rage I Orifice Radius 2.4 Inch[es]
Orifice Diameter 4.8 Inch[es]
in NC assume 3 days to drain
Use 6.0" skimmer with 5.0" diameter orifice.
Basin No. 2
Volume required = 13,316 cf
Volume provided = 30,526 cf
1. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 13.316 Cu Ft Skimmer Size 3.0 Inch
Days to Drain' 2 Days Orifice Radius 1.2 Inch(es]
Orifice Diameter 2.5 Inch(es]
';C assume 3 days to drain
2. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 30.526 Cu Ft Skimmer Size 2.5 Inch
Days to Drain' 5 Days Orifice Radius 1.2 Inch(es)
Orifice Diameter 2.5 Inch[es]
'In NC assume 3 days to drain
Use 2.5" skimmer with 2.5" diameter orifice.
51

Basin No. 3
Volume required = 26,039 cf
Volume provided = 61,945 cf
3. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 26.039 Cu Ft Skimmer Size 4.0 Inch
Days to Drain' 2 Days Orifice Radius 1.6 Inch[es]
Orifice Diameter 3.2 Inch[es]
(•In NC assume 3 days to dram
4. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 61,945 Cu Ft Skimmer Size 4.0 Inch
Days to Drain' 5 Days Orifice Radius 1.6 Inch[es]
Orifice Diameter 3.1 Inch[es]
assun'e
Use 4.0" skimmer with 3.1" orifice.
Basin No.4
Volume required = 7,900 cf
Volume provided = 11,324 cf
1. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 7.900 Cu Ft Skimmer Size 2.5 Inch
Days to Drain' 2 Days Orifice Radius 1.0 Inch[es]
Orifice Diameter 2.0 Inch[es]
in NC assume 3 days to dram
2. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 11.324 Cu Ft Skimmer Size 2.0 Inch
Days to Drain' 5 Days Orifice Radius 0.8 Inch[es]
Orifice Diameter 1.6 Inch[es]
'In NC assume 3 days to drain
Use 2.0" skimmer with 2.0" orifice.
52

Basin No. 5
Volume required = 8,640 cf
Volume provided = 13,121 cf
1. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 8.640 Cu Ft Skimmer Size 2.5 Inch
Days to Drain' 2 Days Orifice Radius 1.0 Inch[es]
Orifice Diameter 2.1 Inch[es]
'In NC assume 3 days to drain
2. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 13,121 Cu Ft Skimmer Size 2.0 Inch
Days to Drain' 5 Days Orifice Radius 0.9 Inch[es]
Orifice Diameter 1.7 Inch[es]
]'In NC assume 3 days to drain
Use 2.5" skimmer with 2.1" orifice.
Basin No. 6
Volume required = 2,880 cf
Volume provided = 11,885 cf
1. Size skimmer using a 2 day drawdown based on required volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 2.880 Cu Ft Skimmer Size 1.5 Inch
I
Days to Drain' 2 Days Orifice Radius 0.7 Inch[es]
Orifice Diameter 1.4 Inch[es]
'in NC assume 3 days to drain
2. Check Skimmer size with a 5 day drawdown per provided volume
Calculate Skimmer Size
Basin Volume in Cubic Feet 11.885 Cu Ft Skimmer Size 2.0 Inch
Days to Drain' 5 Days Orifice Radius 0.8 Inch[esj
Orifice Diameter 1.6 Inch[es]
'In NC assume 3.days to drain
Use 1.5" skimmer with 1.4" orifice.
53

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
SLOPE DRAIN CALCULATIONS
54

CHARLO 1TE-M ECKLENBURG STO RVI WATER DESIG NMANUAL
SLOPE DRAINS
-180 - 10,000
- 168 - 8,000 EXAMPLE (I) (2) (3)
- 156 - 6,000 D•42 Inches (3.5 foot) - 6,
- 6.
- 5,000 0.120 efs - 6.
- 144 - - 6, - - 5.
- 132 - 4,000 +► root it
- 4.
- 3,000 (I) 2.5 e.e - 5' _ ---
4.
- 120 - -
- (2) 2.I 7.4 -
- 2,000 (3) 2.2 7.7 4. - -
- 108 - - - 3. -
- 'D In foot - -3.
- 96 - 1,000 - 3. - _
- 800 - - -
__
- 84 -- 600 _-�- 2 - • 2-
- - 500
- 72 - 400 // e - 2. - -
_ _ EV:- 3 - - 1.6
W - 300 P - 1.5
2 V) _ m
z - 60 v E.:- 200 / ILI •- 1.5
-
- z = w - - #1 &#6
c - 54
100
w - 48 / - 80 " - - #2 &#7
-J a - _
// czi ^ 60 a. - 1.0 - 1.0
42 _ W
o E - 40 HW SCALE YR . - #4
I... - 36 - 30s• • edix
I- - TEMP PIPE
W ,g- hoio _ - #3
Q Gr• •n _ .8ioIelT
8
- 8 27 /000---
project lay -
10
r -.7 .7-
- 24 - 8 .7
• To use scale(2)or(3)project - -
- 21 - 5 horizontolly to scale (I),then -
- a us• straight inclined line through
0 and 0 scales,or reverse os - .6
-
- 3 illustrated. ,- .6 - .6
18 -
-
- 2 -
BUREAU OF PUBLIC ROADS JAN.19d3
15
- -- .5 - .5
- 1.0 HEADWATER SCALES 263 `- •5
REVISED MAY t964
- 12
Figure 5C-5 Headwater Depth for Concrete Pipe Culverts with Inlet Control
Source:www.deldot.gov/inform Aion/pubs_form s1m aivals/road_design/pdf/supp_figures_chap6.pdf
SLOPE DRAINS AREA INTENSITY RUNOFF COEFF. FLOW
1 8.85 AC. 7.26 0.5 32.13 CFS
2 & 7 1.46 AC. 7.26 0.5 5.30 CFS
3 2.87 AC. 7.26 0.5 10.42 CFS
4 1.71 AC. 7.26 0.5 6.21 CFS
5 4.79 AC. 7.26 0.5 17.39 CFS
6 8.55 AC. 7.26 0.5 31.04 CFS
5-32 TEMP. PIPE 3.06 AC. 7.26 0.5 11.11 CFS
55

MCBRIDE SUBDIVISION
HEMB Y BRIDGE, NORTH CAROLINA
TEMPORARY DIVERSION DITCH SWALE
CALCULATIONS
North American Green Erosion Control Materials Design Software was used to determine the
following:
• The vegetation stability when the grass is properly maintained by a homeowner (Class D).
• The temporary liner stability before the swale is stabilized with vegetation.
The drainage areas and swale slopes were determined from the construction drawings. The
retardance class was set to D (grass depth 2-6 inches) in the NAG software for a properly
maintained grass swale to determine vegetation stability. Finally, the swale was modeled as
unvegetated with a S75 temporary liner to determine liner and dirt stability before grass has been
established. Swales that were unstable for any reason either were widened and/or lined with
different temporary liners until stabilization or freeboard requirements were achieved. If the
calculations of the temporary linear showed a velocity of less than 2 fps during a 10-year storm
event then the temporary linear was removed.
See drainage area map C6.0 for largest sub-drainage areas to temporary diversion ditches and
detail sheet C7.4 for depths and widths of each ditch type.
56

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>,(TYP.)
Name (TYP.)
Discharge 6.82
Channel Slope 0.02 Q=CIA f low wKt.on
Channel Bottom Width 1 C=0.50
Left Side Slope 2 1=7.26 in/hr .ir
Right Side Slope 2 A=1.88 AC.
Low Flow Liner Q=6.82 cfs - e.
Retardence Class D 2-6 in NIIIMp\
Vegetation Type Bunch Type 1
Vegetation Density Excellent>95% Ilk
s
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 6.82 cfs 3.67 ft/s 0.75 ft 0.033 1.51 lbs/ft2 0.54 lbs/ft2 2.83 STABLE D
Substrate
S75 Unvegetated Straight 6.82 cfs 3.67 ft/s 0.75 ft 0.033 1.6 Ibs/ft2 0.93 Ibs/ft2 1.72 STABLE D
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 6.82 cfs 3.2 ft/s 0.81 ft 0.039 1.33 lbs/ft2 0.57 lbs/ft2 2.31 STABLE --
Substrate
Unreinforced Straight 6.82 cfs 3.2 ft/s 0.81 ft 0.039 4 Ibs/ft2 1.01 Ibs/ft2 3.95 STABLE --
Vegetation
57

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#1
Name DD#1
Discharge 31.15
Channel Slope 0.015 Q=CIA nc..mr .o,
Channel Bottom Width 4 C=0.50
Left Side Slope 2 1=7.26 in/hr i
Right Side Slope 2 A=8.58 AC.
Low Flow Liner Q=31.15 cfs
•
Retardence Class D 2-6 in
i
Vegetation Type Bunch Type .' _ I
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
S75 Unvegetated Straight 31.15 cfs 4.76 ft/s 1.07 ft 0.031 1.6 lbs/ft2 1 lbs/ft2 1.6 STABLE D
Underlying Straight 31.15 cfs 4.76 ft/s 1.07 ft 0.031 1.51 Ibs/ft2 0.7 Ibs/ft2 2.17 STABLE D
Substrate
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 31.15 cfs 4.37 ft/s 1.14 ft 0.035 4 lbs/ft2 1.06 lbs/ft2 3.76 STABLE --
Vegetation
Underlying Straight 31.15 cfs 4.37 ft/s 1.14 ft 0.035 1.09 Ibs/ft2 0.73 Ibs/ft2 1.48 STABLE --
Substrate
58

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#2
Name DD#2
Discharge 6.23 Q=CIA
Channel Slope 0.02 C=0.50
Channel Bottom Width 2 1=7.26 in/hr t.
Left Side Slope 2 A=1.71 AC.
Right Side Slope 2 Q=6.21 cfs ,
Low Flow Liner NE11.11 - /��
Retardence Class D 2-6 in
Vegetation Type Bunch Type
ami
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 6.23 cfs 3.44 ft/s 0.57 ft 0.033 1.51 lbs/ft2 0.49 lbs/ft2 3.07 STABLE D
Substrate
S75 Unvegetated Straight 6.23 cfs 3.44 ft/s 0.57 ft 0.033 1.6 Ibs/ft2 0.72 Ibs/ft2 2.23 STABLE D
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 6.23 cfs 2.99 ft/s 0.64 ft 0.04 1.4 lbs/ft2 0.54 lbs/ft2 2.6 STABLE --
Substrate
Unreinforced Straight 6.23 cfs 2.99 ft/s 0.64 ft 0.04 4 Ibs/ft2 0.8 Ibs/ft2 5.02 STABLE --
Vegetation
59

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#3
Name DD#3
Discharge 17.39
Channel Slope 0.02 Q=CIA
Channel Bottom Width 2 C=0.50
Left Side Slope 2 1=7.26 in/hr
Right Side Slope 2 A=4.79 AC.
Low Flow Liner Q=17.39 cfs `v
Retardence Class C 6-12 in I
Vegetation Type Bunch Type s -;y
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
S75 Unvegetated Straight 17.39 cfs 4.73 ft/s 0.94 ft 0.031 1.6 lbs/ft2 1.18 lbs/ft2 1.36 STABLE D
Underlying Straight 17.39 cfs 4.73 ft/s 0.94 ft 0.031 1.51 Ibs/ft2 0.74 Ibs/ft2 2.06 STABLE D
Substrate
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 17.39 cfs 3.38 ft/s 1.18 ft 0.049 4 lbs/ft2 1.47 lbs/ft2 2.72 STABLE --
Vegetation
Underlying Straight 17.39 cfs 3.38 ft/s 1.18 ft 0.049 2.11 Ibs/ft2 0.88 Ibs/ft2 2.39 STABLE
Substrate
60

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#4
Name DD#4
Discharge 4.8
Channel Slope 0.01
Q=CIA
C=0.50 •
Channel Bottom Width 1.5
1=7.26 in/hr
Left Side Slope 2 A=1.32 AC. •
Right Side Slope 2
Q=4.79 cfs �cV\
Low Flow Liner --,....
Retardence Class D 2-6 in
Vegetation Type Bunch Type
s s.
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 4.8 cfs 2.4 ft/s 0.69 ft 0.036 1.51 lbs/ft2 0.27 lbs/ft2 5.58 STABLE D
Substrate
S75 Unvegetated Straight 4.8 cfs 2.4 ft/s 0.69 ft 0.036 1.6 Ibs/ft2 0.43 Ibs/ft2 3.69 STABLE D
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 4.8 cfs 1.87 ft/s 0.82 ft 0.05 2.17 lbs/ft2 0.31 lbs/ft2 6.98 STABLE --
Substrate
Unreinforced Straight 4.8 cfs 1.87 ft/s 0.82 ft 0.05 4 Ibs/ft2 0.51 Ibs/ft2 7.83 STABLE --
Vegetation
61

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#4B
Name DD#4B
Discharge 10.42 '
Channel Slope 0.01 Q=CIA
C=0.50
Channel Bottom Width 1.5 ••
I=7.26 in/hr
Left Side Slope 2 A=2.87 AC. lir .
Right Side Slope 2
Q=10.42 cfs $
Low Flow Liner
Retardence Class D 2-6 in , = v - --
Vegetation Type Bunch Type
n
Vegetation Density Excellent>95% 1, ,
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 10.42 cfs 3.02 ft/s 0.99 ft 0.034 1.51 lbs/ft2 0.36 lbs/ft2 4.17 STABLE D
Substrate
S75 Unvegetated Straight 10.42 cfs 3.02 ft/s 0.99 ft 0.034 1.6 Ibs/ft2 0.62 Ibs/ft2 2.59 STABLE D
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 10.42 cfs 2.47 ft/s 1.13 ft 0.045 1.76 lbs/ft2 0.4 lbs/ft2 4.37 STABLE --
Substrate
Unreinforced Straight 10.42 cfs 2.47 ft/s 1.13 ft 0.045 4 Ibs/ft2 0.7 Ibs/ft2 5.7 STABLE
Vegetation
62

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#5
Name DD#5
Discharge 10.89 Q=CIA ,,,...,,,..,,—
Channel Slope 0.02 C=0.50
Channel Bottom Width 2 1=7.26 in/hr
Left Side Slope 2 A=3.00 AC. -
.4411.1111110146
Right Side Slope 2 Q=10.89 cfs
Low Flow Liner I
Retardence Class D 2-6 in ' ' w
Vegetation Type Bunch Type
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 10.89 cfs 4.1 ft/s 0.76 ft 0.032 1.51 lbs/ft2 0.62 lbs/ft2 2.46 STABLE D
Substrate
S75 Unvegetated Straight 10.89 cfs 4.1 ft/s 0.76 ft 0.032 1.6 Ibs/ft2 0.94 Ibs/ft2 1.7 STABLE D
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Underlying Straight 10.89 cfs 3.68 ft/s 0.82 ft 0.037 1.19 lbs/ft2 0.65 lbs/ft2 1.83 STABLE --
Substrate
Unreinforced Straight 10.89 cfs 3.68 ft/s 0.82 ft 0.037 4 Ibs/ft2 1.02 Ibs/ft2 3.93 STABLE --
Vegetation
63

NORTH North American Green
AMERICAN 5401 St. Wendel-Cynthiana Rd.
Poseyville, Indiana 47633
GREEN Tel. [phone]
>Fax [phone]
www.nagreen.com
ECMDS v7.0
CHANNEL ANALYSIS
>>>DD#6
Name DD#6
Discharge 7.84
Channel Slope 0.0385 Q=CIA
C=0.50
Channel Bottom Width 2
1=7.26 in/hr
Left Side Slope 2 A=2.16 AC.
Right Side Slope 2
Q=7.84 cfs
Low Flow Liner116 1.111°
Retardence Class D 2-6 in ter,/
Vegetation Type Bunch Type
Vegetation Density Excellent>95%
Soil Type Sandy Loam(GM)
S75
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
S75 Unvegetated Straight 7.84 cfs 4.91 ft/s 0.52 ft 0.03 1.6 lbs/ft2 1.26 lbs/ft2 1.27 STABLE D
Underlying Straight 7.84 cfs 4.91 ft/s 0.52 ft 0.03 1.51 Ibs/ft2 0.88 Ibs/ft2 1.71 STABLE D
Substrate
Unreinforced Vegetation
Normal Permissible Calculated Safety Staple
Phase Reach Discharge Velocity Mannings N Remarks
Depth Shear Stress Shear Stress Factor Pattern
Unreinforced Straight 7.84 cfs 4.68 ft/s 0.54 ft 0.033 4 lbs/ft2 1.3 lbs/ft2 3.07 STABLE --
Vegetation
Underlying Straight 7.84 cfs 4.68 ft/s 0.54 ft 0.033 0.92 lbs/ft2 0.91 lbs/ft2 1.01 STABLE --
Substrate
64

DETENTION WORKSHEET
for
HEMBY BRIDGE SUBDIVISION
WET POND BMP #1
SAND FILTER BMP #2
Plans Prepared By:
ISAACS
CIVIL ENGINEERING DESIGN AND LAND SURVEYING-0
8720 RED OAK BOULEVARD, SUITE 420
CHARLOTTE, N.C. 28217
PHONE [phone] FAX [phone]
P:Wctive Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention
Worksheet.xls
65

I.Post Construction Controls/Detention Summar3
PROJECT DESCRIPTION: (See Attached Narrative)
PRE-DEVELOPED SUMMARY:
Pre-Developed Data: Area#1 Pre-Developed Data: Area#2
Basin Area: 81.63 ac Basin Area: 2.57 ac
Time of Concentration,Tc pre: 40.9 min Time of Concentration,Tc pre: 5.0 min
(based on the SCS method) (based on the SCS method)
Curve Number,CNpre: 64.3 Curve Number,CNpre: 64.3
POST-DEVELOPED SUMMARY:
Post-Developed Data: Area#1 to BMP#1 Post-Developed Data: Area#4(Bypass)
Basin Area: 39.65 ac Basin Area: 1.67 ac
Time of Concentration,Tc post-on: 5.0 min Time of Concentration,Tc post-on: 5.0 min
(based on the SCS method) (based on the SCS method)
Curve Number,CN post-on: 77.4 Curve Number,CN post-on: 64.3
Post-Developed Data: Area#2 to BMP#2
Basin Area: 5.48 ac
Time of Concentration,Tc post-on: 5.0 min
(based on the SCS method)
Curve Number,CN post-on: 75.2
Post-Developed Data: Area#3(Bypass)
Basin Area: .00 ac
Time of Concentration,Tc post-on: 5.0 min
(based on the SCS method)
Curve Number,CN post-on: 64.3
DETENTION SUMMARY: SCS Unit Hydrograph Method using PondPack v7.5
A.BMP#1 Summary(Wet Pond;
Post Un- Post Routed Max.WSE
Routed(cfs) (cfs) (ft)
1-inch WQv - - 637.27
1-yr,24-hi 62.96 1.83 637.78
10-yr,24-hi 172.87 60.37 638.79
25-yr,24-hi 225.36 106.21 639.41
100-yr,24-hi 311.65 171.60 640.39
B.BMP#2 Summary(Surface Sand Filter;
Post Un- Post Routed Max.WSE
Routed(cfs) (cfs) (ft)
1-inch WQv - - 637.28
1-yr,24-hi 7.55 0.64 637.60
10-yr,24-hi 22.21 4.56 638.90
25-yr,24-hi 29.35 6.61 639.51
100-yr,24-hi 41.17 25.18 640.00
Combined flows at Point of Analysis#1
Pre(cfs) Post Bypass Post Routed
(cfs) (cfs)
1-yr,24-hr 16.95 13.10 13.86
10-yr,24-hr 88.90 66.49 123.74
25-yr,24-hr 128.97 95.59 168.75
100-yr,24-hr 199.47 146.24 284.92
C.Pre-Developed Area 2 and Post-Developed Area
Pre(cfs) Post(cfs)
1-yr,24-hi 1.46 0.95
10-yr,24-hi 6.59 4.28
25-yr,24-hi 9.48 6.16
100-yr,24-hi 14.51 9.43
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention Worksheet.xls
66

Curve Number Calculations(Continued)
A.Pre Developed Area#1
Total Area: 81.63 ac
Hydrologic Weighted CN
Acreage Land Use Soil Type Group CN (Acreage/Total Area)X(CN)
22.59 Woods,Good condition TbB2 B 55 15
14.40 Woods,Good condition ScA C 70 12
3.83 Woods,Good condition ChA C 70 3
22.58 Open space,Good Condition TbB2 B 61 17
14.40 Open space,Good Condition ScA C 74 13
3.83 Open space,Good Condition ChA C 74 3
81.63 CN= 64.3
B.Post Developed Area#1 (TO BMP#1)
Total Area: 39.65 ac
Hydrologic Weighted CN 1
Acreage Land Use Soil Type Group CN (Acreage/Total
14.78 Paved parking lots&roofs TbB2 B 98 37
16.96 Open space,Good Condition TbB2 B 61 26
7.91 Open space,Good Condition ScA C 74 15
39.65 CN= 77.4
C.Post Developed Area#2(TO BMP#2)
Total Area: 5.48 ac
Hydrologic Weighted CN
Acreage Land Use Soil Type Group CN (Acreage/Total Area)X(CN)
2.11 Paved parking lots&roofs TbB2 B 98 38
3.37 Open space,Good Condition TbB2 B 61 38
5.48 CN= 75.2
D.Post Developed CN-Area#3 (BYPASS)
Total Area: 37.42 ac
Hydrologic Weighted CN
Acreage Land Use Soil Type Group CN (Acreage/Total Area)X(CN)
10.34 Open space,Good Condition TbB2 B 61 16.86
4.58 Open space,Good Condition ScA C 74 9.06
3.79 Open space,Good Condition ChA C 74 7.49
10.34 Woods,Good condition TbB2 B 55 15.20
4.58 Woods,Good condition ScA C 70 8.57
3.79 Woods,Good condition ChA C 70 7.09
37.42 CN pre= 64.3
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention Worksheet.xls
67

Curve Number Calculations (Continued)
E. Pre Developed Area#2
Total Area: 2.57 ac
Hydrologic Weighted CN (Acreage/
Acreage Land Use Soil Type Group CN Total Area)X(CN)
.70 Woods, Good condition TbB2 B 55 15
.44 Woods, Good condition ScA C 70 12
.14 Woods, Good condition ChA C 70 4
.71 Open space, Good Condition TbB2 B 61 17
.44 Open space, Good Condition ScA C 74 13
.14 Open space, Good Condition ChA C 74 4
2.57 1 CN = 64.3
F. Post Developed CN-Area#4 (BYPASS)
Total Area: 1.67 ac
IHydrologic Weighted CN (Acreage/
Acreage Land Use Soil Type Group CN Total Area)X(CN)
0.46 Open space, Good Condition TbB2 B 61 16.80
0.29 Open space, Good Condition ScA C 74 12.85
0.08 Open space, Good Condition ChA C 74 3.54
0.46 Woods, Good condition TbB2 B 55 15.15
0.29 Woods, Good condition ScA C 70 12.16
0.09 Woods, Good condition ChA C 70 3.77
1.67 CN pre = 64.3
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention
Worksheet.xls
68

2. Time of Concentration(Tc)
A. Pre Tc - Pre-Developed Area#1
Type of Flow Travel Slope (%) Manning's n Time (min)
Length(ft)
Sheet Unpaved 200.0 2.300% 0.240 23.79
Shallow Conc. Unpaved 1013.0 3.00% - 6.04
Channel1 1150.0 .40% 0.040 11.02
Total n/a n/a n/a Tc Pre=40.85 min.
B. Post Tc - Post-Developed Area#1, Area#2, and Area#3 (Bypass)
Type of Flow Travel Slope (%) Manning's n Time (min)
Length(ft)
Total n/a n/a n/a Tc Post= 5.00 min.
C. Post Tc - Post-Developed Area#3 (Bypass)
Type of Flow Travel I Slope (%) Manning's ni Time (min)
Length (ft)
Sheet Unpaved 100.0 4.00% 0.240 11.0
Shallow Conc. Unpaved 137.0 4.00% - 0.7
Channel 1 1243.0 .65% 0.030 7.3
Total n/a n/a n/a Tc Post= 18.95 min.
D. Pre Tc - Pre-Developed Area#2
Type of Flow Travel Slope (%) Manning's n Time (min)
Length (ft)
Total n/a n/a n/a Tc Post= 5.00 min.
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention
Worksheet.xls
69

3. Storage
A. Storage Summary-BMP#1 (Wet Pond)
Underground Above Ground Total Acc.
Total Ace.
Elevation Volume
Acc.Volume for Volume(cf)
all Structures(cf)* Area(sq.ft.) Inc.Volume(CO Acc.Volume(cf) (ac-ft)
636.50 68803 0 0 0 0.00000
637.00 73185 35497 35497 35497 0.81490
638.00 77622 75404 110901 110901 2.54593
639.00 82116 79869 190770 190770 4.37947
639.50 84384 41625 232395 232395 5.33504
640.00 86667 42763 275157 275157 6.31674
641.00 91274 88971 364128 364128 8.35922
B. Storage Summary-BMP#2(Surface Sand Filter)
Underground Above Ground Total Acc. Total Acc.
Elevation Volume
Acc.Volume for Volume(cf)
all Structures(cf)* Area(sq.ft.) Inc.Volume(cf) Acc.Volume(cf) (ac-ft)
636.00 456.0 0 0 0 0.00000
636.37 1591.0 378.7 378.7 378.7 0.00869
636.50 2269.0 250.9 629.6 629.6 0.01445
637.00 7092.0 2340.3 2969.8 2969.8 0.06818
637.50 8557.0 3912.3 6882.1 6882.1 0.15799
638.00 9574.0 4532.8 11414.8 11414.8 0.26205
638.50 10420.0 4998.5 16413.3 16413.3 0.37680
639.00 11343.0 5440.8 21854.1 21854.1 0.50170
639.50 12029.0 5843.0 27697.1 27697.1 0.63584
640.00 12729.0 6189.5 33886.6 33886.6 0.77793
640.50 13442.0 6542.8 40429.3 40429.3 0.92813
641.00 14170.0 6903.0 47332.3 47332.3 1.08660
642.00 15667.0 14918.5 62250.8 62250.8 1.42908
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention Worksheet.xls
70

4.Discharge
*Refer to storm drainage design calculations for inlet and outlet control.
A.BMP#1 (Wet Pond) Contracted Contracted Suppressed
Sand Orifice 1 Orifice (Orifice Weir 1 Weir 2 Culvert Spillway
4.0 in. 1.50 ft 22.50 ft 2x 24 in. * 30.0 ft
Elevation Total Q
636.50 Inv 637.37 Inv 638.00 Inv 639.50 Inv
Co=.6 Cw=3.3 Cw=3.3 Cw=3.1
636.50
637.00 .24 .24
638.00 .48 2.29 2.77
639.00 .64 8.14 74.26 83.04
639.50 .71 11.12 135.81 147.63 .
640.00 .77 13.83 208.15 32.88 255.63
640.50 .82 16.12 289.59 93.00 399.52
641.00 .87 17.83 378.94 170.85 568.49
Co=orifice coefficient;Cw=weir coefficient
B.BMP#2(Surface Sand Filter) Contracted Contracted Suppressed
Sand Orifice 1 Orifice Orifice Weir 1 Weir Culvert Spillway(W2)
Elevation `f=1.5' 1.00 ft 15.0 ft 36 in.* 20.0 ft Total Q
k=2.0 in/hr 637.50 Inv 639.50 Inv 640.50 Inv
Af=456ft2 Cw=3.3 Cw=3.3 Cw=3.1
636.00
636.50 .028 .03
637.00 .035 .04
638.00 .049 1.06 1.11
638.50 .056 2.66 2.72
639.00 .063 4.28 4.35
640.00 .077 6.58 17.54 24.20
640.50 .084 6.92 49.28 56.29
641.00 .091 6.54 89.93 21.92 118.48
642.00 .106 3.18 190.86 113.90 308.05
Co=orifice coefficient;Cw=weir coefficient
P:Wctive Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Detention Worksheet.xls
71

WET POND CALCULATIONS
BMP Drainage Information:
Proposed BMP No.: 1 (Wet Pond)
Total Drainage Area,AD(Ac.)= 39.65 See Drainage Area Exhibit
Impervious Area(BUA)(Ac.)= 14.78
Percent Impervious Area,IA= 37.3
SCS Curve Number,CN= 77.4 (Hydrologic Group B&C Soil)
Time of Concentration,t,= 5 minutes(minimum)
BUA PER LOT ASSUMED:93 LOTS @ 4,500 SF PER LOT=9.61 AC.
BUA FOR PROPOSED ROADWAYS,AMENITIES&OVERFLOW PARKING:5.17 AC.
Pond Stage-Storage Information:
Perm.Water surface elevation= 636.5
Cumulative Wet Forebay
Main Pool Surface Volume Forebay Percentage of total
Elevation Area Excluding Cumulative Det'n Excluding Surface Area Cumulative Volume(15-20%
Forebays(s.f.) Volume(cu.ft.) Forebays (s.f.) Voluft)me(cu. desired)
(cu.ft.)
630 31370 0 0 2494 0
631 34512 0 0 3618 0
632 37723 0 36,118 4889 4,254
633 41002 0 75,480 6312 9,854
634 44350 0 118,156 7882 16,951
635 47766 0 164,214 9602 25,693
636 51250 0 213,722 11472 36,230
636.5 54473 0 240,153 13125 42,379 17.65
636.5 68803 0 243,735 0 0
637 73185 35,497 272,067 0 0
638 77622 110,901 347,471 0 0
639 82116 190,770 427,340 0 0
639.83 85889 260,492 497,062 0 0
640 86667 275,159 511,731 0 0
641.33 92823 394,520 631,096 0 0
Permanent Pool Calculations:
Permanent Pool Elevation(ft.)= 636.5 See Plan
Permanent Pool Perimeter(ft.)= 1190
Max.Depth Over Shelf(ft.)= 0.5
Width of Submerged shelf(ft.)= 3
Permanent Pool Average Depth(ft.)= 4.67 Per NCDEQ average depth equation 3
SA/DA ratio for 85%Pollutant Removal Efficiency= 1.05 Interpolated From C-3 Wetpond Table 1 in NCDEQ BMP Manual
Required Main Pool Surface Area of Wet Pond(s.f.)= 18,145 =((SA/DA)/100)(Ac.)(43560)
Main Pool Surface Area Provided(s.f.): 54,473 at elevation 636.50 OK
Temporary Water Quality Storage Calculations:
Runoff Coefficient,R„= 0.385 =0.05+0.009(IA)
Water Quality Volume,WQ„(acre-feet)= 1.27 =1.0RVAD/12
Temporary Water Quality Storage Required,WQ v(ft3)= 55,483 =(43,560)(1.0)RVAD/12 (1.27 ac.ft.)
Temporary Water Quality Storage Provided @ elev.: 637.27 (Interpolated from Storage Table)
Orifice Size Provided(inches)= 4.00 Diameter Orifice
Orifice Discharge(cfs)= 0.19 =CDA(2gH0/3)o.5
Drawdown Time(days)= 3.42 days
P:Wctive Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Wet Pond Design Worksheet.xlsx
72

CONCRETE ANCHOR BUOYANCY CALCULATION OS-1
Height of riser= 11.1 ft from spillway of structure to pipe invert
Cross Sectional Area of Riser= 70.0 sf 6'x9' I.D. box w/6"wall thickness
Cross Sectional Area of Concrete = 16.0 sf
Vol. of riser= 777 cf
Wt. of H2O displaced = 48485 lbs
Conc. pad thickness = 30 in
Conc. pad width/length = 13 ft
Vol. of conc. pad = 423 cf
Wt. of H2O displaced = 26364 lbs
Total Wt. of H2O displaced = 74849 lbs
Unit wt. of concrete (pcf) = 150
Wt. of conc. pad (lb.) = 63375
Wt. of conc. box (lb.) = 26640
Total Wt. of Structure (lb.) = 90015
Factor of safety = wt. of Conc. Pad + Conc. Box
wt. of H2O displaced
F.S.= 1.20
73

SAND FILTER CALCULATIONS
BMP Drainage Information:
Proposed BMP No.: 2(Sand Filter)
Total Drainage Area,AD(Ac.)= 5.48 See Drainage Area Exhibit
Impervious Area(BUA)(Ac.)= 2.11 Total Proposed Impervious Area
Percent Impervious Area,IA= 38.5
SCS Curve Number,CN= 75.2 (Hydrologic Group B&C Soils)
Time of Concentration,t.= 5 minutes(minimum)
Stage-Storage Information:
Top of Filter Media= 636.00
Forebay Forebay Sand Area Sand Area Sand Area Total Total Total
Forebay Surface Total Surface Cumulative
Elevation Incremental Cumulative Surface Area Incremental Cumulative Incremental Cumulative
Area(ft2) Volume(ft3) Volume(ft3) (ft2) Volume(ft3) Volume(ft3) Area(ft2) Volume(ft3) Volume(ft3) Volume(ac-
ft)
636.00 0 0 0 456 0 0 456 0 0 0.0000
636.37 1 0 0 1,591 379 379 1,592 379 379 0.0087
636.50 385 25 25 1,884 226 605 2,269 251 630 0.0145
637.00 3,465 963 988 3,627 1,378 1,982 7,092 2,340 2,970 0.0682
637.50 4,596 2,015 3,003 3,961 1,897 3,879 8,557 3,912 6,882 0.1580
638.00 5,266 2,466 5,468 4,308 2,067 5,947 9,574 4,533 11,415 0.2621
638.50 5,753 2,755 8,223 4,667 2,244 8,190 10,420 4,999 16,414 0.3768
639.00 0 8,223 11,343 4,003 12,193 11,343 5,441 21,854 0.5017
639.50 0 8,223 12,029 5,843 18,036 12,029 5,843 27,697 0.6358
640.00 0 8,223 12,729 6,190 24,225 12,729 6,190 33,887 0.7779
640.50 0 8,223 13,442 6,543 30,768 13,442 6,543 40,430 0.9281
641.00 0 8,223 14,170 6,903 37,671 14,170 6,903 47,333 1.0866
642.00 0 8,223 15,667 14,919 52,590 15,667 14,919 62,251 1.4291
Compute Water Quality Volume(WQ„)-Schueler Method:
Runoff Coefficient,RV= 0.397 =0.05+0.009(IA)
Water Quality Volume,WQv(acre-feet)= 0.18 =1.0RVAD/12
Water Quality Volume,WQv(ft3)= 7,888 =(43,560)(1.0)RvAo/12
Adjusted WQv Treatment Volume(75%)= 5,916
Water Quality Storage Elevation= 637.28 (From Stage-Storage)
Filter Bed Surface Area:
Depth of sand filter bed,df(ft)= 1.5 =minimum depth of 1.5 ft(Per NCDEQ Manual)
Coefficient of permeability for sand filter bed,k(ft/day)= 4 =2.0 inch/hour
Time required to drain WQV through filter bed,tf(day)= 2.125 =51 hours
Average head,hf(ft)= 0.79 =0.5*WQV Storage Depth
Required Surface Area for Filter Bed,Af(ft)= 456 =(WQv)(df)/(k)(tf)(hf+df) Darcy's Equation
Provided Surface Area for Filter Bed,Af(ft)= 456
Stage-Discharge for Sand Filter Media:
Af=(WQV)(df)/[(k)(ttf)(hf+df)] Darcy's Equation
(WQv)/(tf)=Q.=(Af)(k)(hf+df)/(df)
Af=provided surface area of filter bed(ft2)
df=filter bed depth(ft)
k=coefficient of permeability of filter media(ft/day)
hf=average height of water above filter bed(ft)
Elevation hf(ft) Q.(cf/day) Qv(cfs) 10*Q.(cfs)
636.00 0.00 0 0.000 0.000
636.37 0.37 2,274 0.026 0.263
636.50 0.50 2,432 0.028 0.281
637.00 1.00 3,040 0.035 0.352
637.50 1.50 3,648 0.042 0.422
638.00 2.00 4,256 0.049 0.493
638.50 2.50 4,864 0.056 0.563
639.00 3.00 5,472 0.063 0.633
639.50 3.50 6,080 0.070 0.704
640.00 4.00 6,688 0.077 0.774
640.50 4.50 7,296 0.084 0.844
641.50 5.50 8,512 0.099 0.985
641.00 5.00 7,904 0.091 0.915
74
\\ISAACSGC01\Projects\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Sand Filter Design Worksheet.xls

Compute Perforation Capacity
Number of pipes: 4
Length of pipe: 12
Number of perforations: 640 holes
50 Percent of perforations: 320
Capacity of one hole: 0.0083 cfs CA(2gh)^0.5
Total Capacity: 2.64 cfs
Compute Underdrain Capcity
Pipe diameter: 8 inches
Pipe slope: 0.005 ft/ft
Capacity of pipe: 0.93 cfs
Assume fifty percent clogging: 0.46 cfs
75
\\ISAACSGC01\Projects\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Sand Filter Design Worksheet.xls

CONCRETE ANCHOR BUOYANCY CALCULATION OS-2
Height of riser= 9.5 ft from spillway of structure to pipe invert
Cross Sectional Area of Riser= 25.0 sf 4'x4' I.D. box w/6"wall thickness
Cross Sectional Area of Concrete = 9.0 sf
Vol. of riser= 238 cf
Wt. of H2O displaced = 14820 lbs
Conc. pad thickness = 24 in
Conc. pad width/length = 9 ft
Vol. of conc. pad = 162 cf
Wt. of H2O displaced = 10109 lbs
Total Wt. of H2O displaced = 24929 lbs
Unit wt. of concrete (pcf) = 150
Wt. of conc. pad (lb.) = 24300
Wt. of conc. box (lb.) = 12825
Total Wt. of Structure (lb.) = 37125
Factor of safety = wt. of Conc. Pad + Conc. Box
wt. of H2O displaced
F.S.= 1.49
P:\Active Projects\DRB Group\Hemby Bridge Development 20155\Engineering\Calculations\BMP\20155-Sand
Filter Design Worksheet.xls
76

Pe 1 Q PRE OUT 1
PO 2 A PRE OUT 2
,441BMP 1 OS(Entrance)
e�A
706,
POST OUT 1
POST DintyrAcc A
�Q ti
O�'
J
BMP 2 OS(Entrance)
POW2
POST I° aYPASS 0 POST OUT 2
20155-Pondpack Model.ppc
8/10/2023 The Isaacs Group
77

Subsection: Master Network Summary
Catchments Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (hours) (ft3/s)
(years) (ac-ft)
PRE DA-1 1-year 1 3.026 12.425 16.95
PRE DA-1 10-year 10 11.528 12.350 88.90
PRE DA-1 25-year 25 16.213 12.325 128.97
PRE DA-1 100-yr 100 24.490 12.325 199.47
POST DA-1 1-year 1 3.431 11.925 62.96
POST DA-1 10-year 10 9.174 11.925 172.87
POST DA-1 25-year 25 12.005 11.925 225.36
POST DA-1 100-yr 100 16.763 11.925 311.65
POST DA-3 BYPASS 1-year 1 1.387 12.125 13.10
POST DA-3 BYPASS 10-year 10 5.284 12.100 66.49
POST DA-3 BYPASS 25-year 25 7.432 12.100 95.59
POST DA-3 BYPASS 100-yr 100 11.226 12.100 146.24
POST DA-2 1-year 1 0.420 11.925 7.55
POST DA-2 10-year 10 1.179 11.925 22.21
POST DA-2 25-year 25 1.559 11.925 29.35
POST DA-2 100-yr 100 2.202 11.925 41.17
PRE-DA-2 1-year 1 0.095 12.000 1.46
PRE-DA-2 10-year 10 0.363 11.925 6.59
PRE-DA-2 25-year 25 0.510 11.925 9.48
PRE-DA-2 100-yr 100 0.771 11.925 14.51
POST DA-4 BYPASS 1-year 1 0.062 12.000 0.95
POST DA-4 BYPASS 10-year 10 0.236 11.925 4.28
POST DA-4 BYPASS 25-year 25 0.332 11.925 6.16
POST DA-4 BYPASS 100-yr 100 0.501 11.925 9.43
Node Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow
Event Volume (hours) (ft3/s)
(years) (ac-ft)
PRE OUT 1 1-year 1 3.026 12.425 16.95
PRE OUT 1 10-year 10 11.528 12.350 88.90
PRE OUT 1 25-year 25 16.213 12.325 128.97
PRE OUT 1 100-yr 100 24.490 12.325 199.47
POST OUT 1 1-year 1 4.634 12.125 13.86
POST OUT 1 10-year 10 14.985 12.100 123.74
POST OUT 1 25-year 25 20.333 12.100 168.71
POST OUT 1 100-yr 100 29.524 12.075 284.91
PRE OUT 2 1-year 1 0.095 12.000 1.46
PRE OUT 2 10-year 10 0.363 11.925 6.59
PRE OUT 2 25-year 25 0.510 11.925 9.48
PRE OUT 2 100-yr 100 0.771 11.925 14.51
POST OUT 2 1-year 1 0.062 12.000 0.95
POST OUT 2 10-year 10 0.236 11.925 4.28
POST OUT 2 25-year 25 0.332 11.925 6.16
POST OUT 2 100-yr 100 0.501 11.925 9.43
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
78

Subsection: Master Network Summary
Pond Summary
Label Scenario Return Hydrograph Time to Peak Peak Flow Maximum Maximum
Event Volume (hours) (ft3/s) Water Pond Storage
(years) (ac-ft) Surface (ac-ft)
Elevation
(ft)
BMP 1 (IN) 1-year 1 3.431 11.925 62.96 (N/A) (N/A)
BMP 1 (OUT) 1-year 1 2.827 15.875 1.83 637.78 2.169
BMP 1 (IN) 10-year 10 9.174 11.925 172.87 (N/A) (N/A)
BMP 1 (OUT) 10-year 10 8.522 12.100 52.72 638.79 3.992
BMP 1 (IN) 25-year 25 12.005 11.925 225.36 (N/A) (N/A)
BMP 1 (OUT) 25-year 25 11.343 12.100 66.69 639.41 5.167
BMP 1 (IN) 100-yr 100 16.763 11.925 311.65 (N/A) (N/A)
BMP 1 (OUT) 100-yr 100 16.096 12.075 115.42 640.39 7.115
BMP 2(IN) 1-year 1 0.420 11.925 7.55 (N/A) (N/A)
BMP 2(OUT) 1-year 1 0.420 12.825 0.64 637.60 0.179
BMP 2(IN) 10-year 10 1.179 11.925 22.21 (N/A) (N/A)
BMP 2(OUT) 10-year 10 1.179 12.125 4.56 638.90 0.477
BMP 2(IN) 25-year 25 1.559 11.925 29.35 (N/A) (N/A)
BMP 2(OUT) 25-year 25 1.559 12.125 6.59 639.51 0.639
BMP 2(IN) 100-yr 100 2.202 11.925 41.17 (N/A) (N/A)
BMP 2(OUT) 100-yr 100 2.202 12.050 25.17 640.00 0.780
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
79

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
0.000 0.000 0.000 0.000 0.000 0.000
0.125 0.000 0.000 0.000 0.000 0.000
0.250 0.000 0.000 0.000 0.000 0.000
0.375 0.000 0.000 0.000 0.000 0.000
0.500 0.000 0.000 0.000 0.000 0.000
0.625 0.000 0.000 0.000 0.000 0.000
0.750 0.000 0.000 0.000 0.000 0.000
0.875 0.000 0.000 0.000 0.000 0.000
1.000 0.000 0.000 0.000 0.000 0.000
1.125 0.000 0.000 0.000 0.000 0.000
1.250 0.000 0.000 0.000 0.000 0.000
1.375 0.000 0.000 0.000 0.000 0.000
1.500 0.000 0.000 0.000 0.000 0.000
1.625 0.000 0.000 0.000 0.000 0.000
1.750 0.000 0.000 0.000 0.000 0.000
1.875 0.000 0.000 0.000 0.000 0.000
2.000 0.000 0.000 0.000 0.000 0.000
2.125 0.000 0.000 0.000 0.000 0.000
2.250 0.000 0.000 0.000 0.000 0.000
2.375 0.000 0.000 0.000 0.000 0.000
2.500 0.000 0.000 0.000 0.000 0.000
2.625 0.000 0.000 0.000 0.000 0.000
2.750 0.000 0.000 0.000 0.000 0.000
2.875 0.000 0.000 0.000 0.000 0.000
3.000 0.000 0.000 0.000 0.000 0.000
3.125 0.000 0.000 0.000 0.000 0.000
3.250 0.000 0.000 0.000 0.000 0.000
3.375 0.000 0.000 0.000 0.000 0.000
3.500 0.000 0.000 0.000 0.000 0.000
3.625 0.000 0.000 0.000 0.000 0.000
3.750 0.000 0.000 0.000 0.000 0.000
3.875 0.000 0.000 0.000 0.000 0.000
4.000 0.000 0.000 0.000 0.000 0.000
4.125 0.000 0.000 0.000 0.000 0.000
4.250 0.000 0.000 0.000 0.000 0.000
4.375 0.000 0.000 0.000 0.000 0.000
4.500 0.000 0.000 0.000 0.000 0.000
4.625 0.000 0.000 0.000 0.000 0.000
4.750 0.000 0.000 0.000 0.000 0.000
4.875 0.000 0.000 0.000 0.000 0.000
5.000 0.000 0.000 0.000 0.000 0.000
5.125 0.000 0.000 0.000 0.000 0.000
5.250 0.000 0.000 0.000 0.000 0.000
5.375 0.000 0.000 0.000 0.000 0.000
5.500 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
80

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
5.625 0.000 0.000 0.000 0.000 0.000
5.750 0.000 0.000 0.000 0.000 0.000
5.875 0.000 0.000 0.000 0.000 0.000
6.000 0.000 0.000 0.000 0.000 0.000
6.125 0.000 0.000 0.000 0.000 0.000
6.250 0.000 0.000 0.000 0.000 0.000
6.375 0.000 0.000 0.000 0.000 0.000
6.500 0.000 0.000 0.000 0.000 0.000
6.625 0.000 0.000 0.000 0.000 0.000
6.750 0.000 0.000 0.000 0.000 0.000
6.875 0.000 0.000 0.000 0.000 0.000
7.000 0.000 0.000 0.000 0.000 0.000
7.125 0.000 0.000 0.000 0.000 0.000
7.250 0.000 0.000 0.000 0.000 0.000
7.375 0.000 0.000 0.000 0.000 0.000
7.500 0.000 0.000 0.000 0.000 0.000
7.625 0.000 0.000 0.000 0.000 0.000
7.750 0.000 0.000 0.000 0.000 0.000
7.875 0.000 0.000 0.000 0.000 0.000
8.000 0.000 0.000 0.000 0.000 0.000
8.125 0.000 0.000 0.000 0.000 0.000
8.250 0.000 0.000 0.000 0.000 0.000
8.375 0.000 0.000 0.000 0.000 0.000
8.500 0.000 0.000 0.000 0.000 0.000
8.625 0.000 0.000 0.000 0.000 0.000
8.750 0.000 0.000 0.000 0.000 0.000
8.875 0.000 0.000 0.000 0.000 0.000
9.000 0.000 0.000 0.000 0.000 0.000
9.125 0.000 0.000 0.000 0.000 0.000
9.250 0.000 0.000 0.000 0.000 0.000
9.375 0.000 0.000 0.000 0.000 0.000
9.500 0.000 0.000 0.000 0.000 0.000
9.625 0.000 0.000 0.000 0.000 0.000
9.750 0.000 0.000 0.000 0.000 0.000
9.875 0.000 0.000 0.000 0.000 0.000
10.000 0.000 0.000 0.000 0.000 0.000
10.125 0.000 0.000 0.000 0.000 0.000
10.250 0.000 0.000 0.000 0.000 0.000
10.375 0.000 0.000 0.000 0.000 0.000
10.500 0.000 0.000 0.000 0.000 0.000
10.625 0.001 0.001 0.001 0.001 0.002
10.750 0.002 0.002 0.003 0.003 0.004
10.875 0.005 0.005 0.006 0.007 0.008
11.000 0.009 0.010 0.011 0.012 0.013
11.125 0.015 0.016 0.018 0.019 0.021
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
81

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
11.250 0.023 0.025 0.027 0.030 0.032
11.375 0.035 0.038 0.041 0.044 0.047
11.500 0.051 0.055 0.060 0.066 0.074
11.625 0.084 0.096 0.113 0.133 0.158
11.750 0.188 0.227 0.273 0.327 0.397
11.875 0.489 0.600 0.725 0.853 0.977
12.000 1.095 1.208 1.304 1.373 1.420
12.125 1.455 1.483 1.508 1.531 1.553
12.250 1.573 1.593 1.612 1.631 1.648
12.375 1.665 1.681 1.697 1.711 1.725
12.500 1.738 1.750 1.762 1.773 1.783
12.625 1.793 1.803 1.813 1.822 1.831
12.750 1.840 1.849 1.858 1.866 1.874
12.875 1.882 1.889 1.897 1.904 1.911
13.000 1.918 1.925 1.931 1.937 1.944
13.125 1.950 1.955 1.961 1.967 1.972
13.250 1.978 1.983 1.988 1.993 1.998
13.375 2.003 2.007 2.012 2.016 2.021
13.500 2.025 2.029 2.033 2.037 2.040
13.625 2.044 2.048 2.051 2.055 2.058
13.750 2.061 2.064 2.067 2.070 2.073
13.875 2.076 2.079 2.081 2.084 2.086
14.000 2.089 2.091 2.093 2.095 2.098
14.125 2.100 2.102 2.104 2.106 2.108
14.250 2.110 2.111 2.113 2.115 2.117
14.375 2.119 2.120 2.122 2.124 2.125
14.500 2.127 2.128 2.130 2.131 2.133
14.625 2.134 2.136 2.137 2.138 2.140
14.750 2.141 2.142 2.144 2.145 2.146
14.875 2.147 2.148 2.149 2.150 2.151
15.000 2.152 2.153 2.154 2.155 2.156
15.125 2.157 2.157 2.158 2.159 2.160
15.250 2.160 2.161 2.162 2.162 2.163
15.375 2.163 2.164 2.164 2.165 2.165
15.500 2.166 2.166 2.167 2.167 2.167
15.625 2.167 2.168 2.168 2.168 2.168
15.750 2.168 2.169 2.169 2.169 2.169
15.875 2.169 2.169 2.169 2.169 2.169
16.000 2.169 2.168 2.168 2.168 2.168
16.125 2.168 2.167 2.167 2.167 2.167
16.250 2.167 2.166 2.166 2.166 2.166
16.375 2.165 2.165 2.165 2.164 2.164
16.500 2.164 2.163 2.163 2.163 2.162
16.625 2.162 2.162 2.161 2.161 2.161
16.750 2.160 2.160 2.160 2.159 2.159
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
82

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
16.875 2.158 2.158 2.158 2.157 2.157
17.000 2.156 2.156 2.155 2.155 2.154
17.125 2.154 2.153 2.153 2.152 2.152
17.250 2.151 2.151 2.150 2.150 2.149
17.375 2.149 2.148 2.148 2.147 2.147
17.500 2.146 2.145 2.145 2.144 2.144
17.625 2.143 2.142 2.142 2.141 2.141
17.750 2.140 2.139 2.139 2.138 2.137
17.875 2.137 2.136 2.135 2.135 2.134
18.000 2.133 2.133 2.132 2.131 2.130
18.125 2.130 2.129 2.128 2.128 2.127
18.250 2.126 2.125 2.125 2.124 2.123
18.375 2.122 2.122 2.121 2.120 2.119
18.500 2.118 2.118 2.117 2.116 2.115
18.625 2.114 2.113 2.113 2.112 2.111
18.750 2.110 2.109 2.108 2.108 2.107
18.875 2.106 2.105 2.104 2.103 2.102
19.000 2.101 2.100 2.100 2.099 2.098
19.125 2.097 2.096 2.095 2.094 2.093
19.250 2.092 2.091 2.090 2.089 2.088
19.375 2.087 2.086 2.085 2.084 2.083
19.500 2.082 2.081 2.080 2.079 2.078
19.625 2.077 2.076 2.075 2.074 2.073
19.750 2.072 2.071 2.070 2.069 2.068
19.875 2.067 2.066 2.065 2.064 2.063
20.000 2.062 2.061 2.059 2.058 2.057
20.125 2.056 2.055 2.054 2.053 2.052
20.250 2.051 2.050 2.049 2.048 2.047
20.375 2.046 2.045 2.043 2.042 2.041
20.500 2.040 2.039 2.038 2.037 2.036
20.625 2.035 2.034 2.033 2.032 2.031
20.750 2.030 2.029 2.028 2.027 2.026
20.875 2.025 2.024 2.023 2.022 2.022
21.000 2.021 2.020 2.019 2.018 2.017
21.125 2.016 2.015 2.014 2.013 2.012
21.250 2.011 2.010 2.009 2.008 2.007
21.375 2.007 2.006 2.005 2.004 2.003
21.500 2.002 2.001 2.000 1.999 1.998
21.625 1.998 1.997 1.996 1.995 1.994
21.750 1.993 1.992 1.991 1.991 1.990
21.875 1.989 1.988 1.987 1.986 1.985
22.000 1.985 1.984 1.983 1.982 1.981
22.125 1.980 1.980 1.979 1.978 1.977
22.250 1.976 1.975 1.975 1.974 1.973
22.375 1.972 1.971 1.971 1.970 1.969
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
83

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
22.500 1.968 1.967 1.967 1.966 1.965
22.625 1.964 1.963 1.963 1.962 1.961
22.750 1.960 1.960 1.959 1.958 1.957
22.875 1.957 1.956 1.955 1.954 1.954
23.000 1.953 1.952 1.951 1.951 1.950
2 3.12 5 1.949 1.948 1.948 1.947 1.946
23.250 1.945 1.945 1.944 1.943 1.942
23.375 1.942 1.941 1.940 1.940 1.939
23.500 1.938 1.937 1.937 1.936 1.935
23.625 1.935 1.934 1.933 1.933 1.932
23.750 1.931 1.930 1.930 1.929 1.928
23.875 1.928 1.927 1.926 1.926 1.925
24.000 1.924 1.924 1.923 1.921 1.919
24.125 1.917 1.914 1.912 1.909 1.907
24.250 1.905 1.902 1.900 1.897 1.895
24.375 1.893 1.890 1.888 1.886 1.883
24.500 1.881 1.879 1.876 1.874 1.872
24.625 1.870 1.867 1.865 1.863 1.861
24.750 1.859 1.856 1.854 1.852 1.850
24.875 1.848 1.846 1.844 1.842 1.840
25.000 1.837 1.835 1.833 1.831 1.829
25.125 1.827 1.825 1.823 1.821 1.819
25.250 1.817 1.815 1.813 1.811 1.809
25.375 1.808 1.806 1.804 1.802 1.800
25.500 1.798 1.796 1.794 1.793 1.791
25.625 1.789 1.787 1.785 1.783 1.782
25.750 1.780 1.778 1.776 1.775 1.773
25.875 1.771 1.769 1.768 1.766 1.764
26.000 1.763 1.761 1.759 1.758 1.756
26.125 1.754 1.753 1.751 1.749 1.748
26.250 1.746 1.745 1.743 1.741 1.740
26.375 1.738 1.737 1.735 1.734 1.732
26.500 1.731 1.729 1.728 1.726 1.725
26.625 1.723 1.722 1.720 1.719 1.717
26.750 1.716 1.714 1.713 1.712 1.710
26.875 1.709 1.707 1.706 1.705 1.703
27.000 1.702 1.700 1.699 1.698 1.696
27.125 1.695 1.694 1.692 1.691 1.690
27.250 1.688 1.687 1.686 1.685 1.683
27.375 1.682 1.681 1.679 1.678 1.677
27.500 1.676 1.674 1.673 1.672 1.671
27.625 1.670 1.668 1.667 1.666 1.665
27.750 1.663 1.662 1.661 1.660 1.659
27.875 1.657 1.656 1.655 1.654 1.653
28.000 1.651 1.650 1.649 1.648 1.647
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
84

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
28.125 1.645 1.644 1.643 1.642 1.641
28.250 1.640 1.638 1.637 1.636 1.635
28.375 1.634 1.633 1.631 1.630 1.629
28.500 1.628 1.627 1.626 1.625 1.624
28.625 1.622 1.621 1.620 1.619 1.618
28.750 1.617 1.616 1.615 1.613 1.612
28.875 1.611 1.610 1.609 1.608 1.607
29.000 1.606 1.605 1.604 1.603 1.602
29.125 1.600 1.599 1.598 1.597 1.596
29.250 1.595 1.594 1.593 1.592 1.591
29.375 1.590 1.589 1.588 1.587 1.586
29.500 1.585 1.584 1.583 1.582 1.581
29.625 1.580 1.578 1.577 1.576 1.575
29.750 1.574 1.573 1.572 1.571 1.570
29.875 1.569 1.568 1.567 1.566 1.565
30.000 1.564 1.563 1.562 1.562 1.561
30.125 1.560 1.559 1.558 1.557 1.556
30.250 1.555 1.554 1.553 1.552 1.551
30.375 1.550 1.549 1.548 1.547 1.546
30.500 1.545 1.544 1.543 1.542 1.541
30.625 1.541 1.540 1.539 1.538 1.537
30.750 1.536 1.535 1.534 1.533 1.532
30.875 1.531 1.530 1.530 1.529 1.528
31.000 1.527 1.526 1.525 1.524 1.523
31.125 1.522 1.521 1.521 1.520 1.519
31.250 1.518 1.517 1.516 1.515 1.514
31.375 1.514 1.513 1.512 1.511 1.510
31.500 1.509 1.508 1.508 1.507 1.506
31.625 1.505 1.504 1.503 1.503 1.502
31.750 1.501 1.500 1.499 1.498 1.498
31.875 1.497 1.496 1.495 1.494 1.493
32.000 1.493 1.492 1.491 1.490 1.489
32.125 1.489 1.488 1.487 1.486 1.485
32.250 1.485 1.484 1.483 1.482 1.481
32.375 1.481 1.480 1.479 1.478 1.477
32.500 1.477 1.476 1.475 1.474 1.474
32.625 1.473 1.472 1.471 1.471 1.470
32.750 1.469 1.468 1.467 1.467 1.466
32.875 1.465 1.464 1.464 1.463 1.462
33.000 1.461 1.461 1.460 1.459 1.459
33.125 1.458 1.457 1.456 1.456 1.455
33.250 1.454 1.453 1.453 1.452 1.451
33.375 1.451 1.450 1.449 1.448 1.448
33.500 1.447 1.446 1.445 1.445 1.444
33.625 1.443 1.443 1.442 1.441 1.440
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
85

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
33.750 1.440 1.439 1.438 1.437 1.437
33.875 1.436 1.435 1.435 1.434 1.433
34.000 1.432 1.432 1.431 1.430 1.430
34.125 1.429 1.428 1.427 1.427 1.426
34.250 1.425 1.425 1.424 1.423 1.422
34.375 1.422 1.421 1.420 1.420 1.419
34.500 1.418 1.417 1.417 1.416 1.415
34.625 1.415 1.414 1.413 1.412 1.412
34.750 1.411 1.410 1.410 1.409 1.408
34.875 1.407 1.407 1.406 1.405 1.405
35.000 1.404 1.403 1.402 1.402 1.401
35.125 1.400 1.400 1.399 1.398 1.397
35.250 1.397 1.396 1.395 1.395 1.394
35.375 1.393 1.393 1.392 1.391 1.390
35.500 1.390 1.389 1.388 1.388 1.387
35.625 1.386 1.385 1.385 1.384 1.383
35.750 1.383 1.382 1.381 1.381 1.380
35.875 1.379 1.378 1.378 1.377 1.376
36.000 1.376 1.375 1.374 1.374 1.373
36.125 1.372 1.372 1.371 1.370 1.369
36.250 1.369 1.368 1.367 1.367 1.366
36.375 1.365 1.365 1.364 1.363 1.362
36.500 1.362 1.361 1.360 1.360 1.359
36.625 1.358 1.358 1.357 1.356 1.356
36.750 1.355 1.354 1.353 1.353 1.352
36.875 1.351 1.351 1.350 1.349 1.349
37.000 1.348 1.347 1.347 1.346 1.345
37.125 1.344 1.344 1.343 1.342 1.342
37.250 1.341 1.340 1.340 1.339 1.338
37.375 1.338 1.337 1.336 1.336 1.335
37.500 1.334 1.334 1.333 1.332 1.331
37.625 1.331 1.330 1.329 1.329 1.328
37.750 1.327 1.327 1.326 1.325 1.325
37.875 1.324 1.323 1.323 1.322 1.321
38.000 1.321 1.320 1.319 1.319 1.318
38.125 1.317 1.317 1.316 1.315 1.314
38.250 1.314 1.313 1.312 1.312 1.311
38.375 1.310 1.310 1.309 1.308 1.308
38.500 1.307 1.306 1.306 1.305 1.304
38.625 1.304 1.303 1.302 1.302 1.301
38.750 1.300 1.300 1.299 1.298 1.298
38.875 1.297 1.296 1.296 1.295 1.294
39.000 1.294 1.293 1.292 1.292 1.291
39.125 1.290 1.290 1.289 1.288 1.288
39.250 1.287 1.286 1.286 1.285 1.284
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
86

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
39.375 1.284 1.283 1.282 1.282 1.281
39.500 1.280 1.280 1.279 1.278 1.278
39.625 1.277 1.276 1.276 1.275 1.274
39.750 1.274 1.273 1.272 1.272 1.271
39.875 1.270 1.270 1.269 1.268 1.268
40.000 1.267 1.266 1.266 1.265 1.264
40.125 1.264 1.263 1.262 1.262 1.261
40.250 1.260 1.260 1.259 1.258 1.258
40.375 1.257 1.256 1.256 1.255 1.255
40.500 1.254 1.253 1.253 1.252 1.251
40.625 1.251 1.250 1.249 1.249 1.248
40.750 1.247 1.247 1.246 1.245 1.245
40.875 1.244 1.243 1.243 1.242 1.241
41.000 1.241 1.240 1.240 1.239 1.238
41.125 1.238 1.237 1.236 1.236 1.235
41.250 1.234 1.234 1.233 1.232 1.232
41.375 1.231 1.230 1.230 1.229 1.229
41.500 1.228 1.227 1.227 1.226 1.225
41.625 1.225 1.224 1.223 1.223 1.222
41.750 1.221 1.221 1.220 1.219 1.219
41.875 1.218 1.218 1.217 1.216 1.216
42.000 1.215 1.214 1.214 1.213 1.212
42.125 1.212 1.211 1.211 1.210 1.209
42.250 1.209 1.208 1.207 1.207 1.206
42.375 1.205 1.205 1.204 1.203 1.203
42.500 1.202 1.202 1.201 1.200 1.200
42.625 1.199 1.198 1.198 1.197 1.197
42.750 1.196 1.195 1.195 1.194 1.193
42.875 1.193 1.192 1.191 1.191 1.190
43.000 1.190 1.189 1.188 1.188 1.187
43.125 1.186 1.186 1.185 1.185 1.184
43.250 1.183 1.183 1.182 1.181 1.181
43.375 1.180 1.179 1.179 1.178 1.178
43.500 1.177 1.176 1.176 1.175 1.174
43.625 1.174 1.173 1.173 1.172 1.171
43.750 1.171 1.170 1.169 1.169 1.168
43.875 1.168 1.167 1.166 1.166 1.165
44.000 1.164 1.164 1.163 1.163 1.162
44.125 1.161 1.161 1.160 1.159 1.159
44.250 1.158 1.158 1.157 1.156 1.156
44.375 1.155 1.155 1.154 1.153 1.153
44.500 1.152 1.151 1.151 1.150 1.150
44.625 1.149 1.148 1.148 1.147 1.146
44.750 1.146 1.145 1.145 1.144 1.143
44.875 1.143 1.142 1.142 1.141 1.140
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
87

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
45.000 1.140 1.139 1.138 1.138 1.137
45.125 1.137 1.136 1.135 1.135 1.134
45.250 1.134 1.133 1.132 1.132 1.131
45.375 1.131 1.130 1.129 1.129 1.128
45.500 1.128 1.127 1.126 1.126 1.125
45.625 1.124 1.124 1.123 1.123 1.122
45.750 1.121 1.121 1.120 1.120 1.119
45.875 1.118 1.118 1.117 1.117 1.116
46.000 1.115 1.115 1.114 1.114 1.113
46.125 1.112 1.112 1.111 1.111 1.110
46.250 1.109 1.109 1.108 1.108 1.107
46.375 1.106 1.106 1.105 1.104 1.104
46.500 1.103 1.103 1.102 1.101 1.101
46.625 1.100 1.100 1.099 1.098 1.098
46.750 1.097 1.097 1.096 1.096 1.095
46.875 1.094 1.094 1.093 1.093 1.092
47.000 1.091 1.091 1.090 1.090 1.089
47.125 1.088 1.088 1.087 1.087 1.086
47.250 1.085 1.085 1.084 1.084 1.083
47.375 1.082 1.082 1.081 1.081 1.080
47.500 1.079 1.079 1.078 1.078 1.077
47.625 1.076 1.076 1.075 1.075 1.074
47.750 1.074 1.073 1.072 1.072 1.071
47.875 1.071 1.070 1.069 1.069 1.068
48.000 1.068 1.067 1.066 1.066 1.065
48.125 1.065 1.064 1.064 1.063 1.062
48.250 1.062 1.061 1.061 1.060 1.059
48.375 1.059 1.058 1.058 1.057 1.057
48.500 1.056 1.055 1.055 1.054 1.054
48.625 1.053 1.052 1.052 1.051 1.051
48.750 1.050 1.050 1.049 1.048 1.048
48.875 1.047 1.047 1.046 1.045 1.045
49.000 1.044 1.044 1.043 1.043 1.042
49.125 1.041 1.041 1.040 1.040 1.039
49.250 1.039 1.038 1.037 1.037 1.036
49.375 1.036 1.035 1.034 1.034 1.033
49.500 1.033 1.032 1.032 1.031 1.030
49.625 1.030 1.029 1.029 1.028 1.028
49.750 1.027 1.026 1.026 1.025 1.025
49.875 1.024 1.024 1.023 1.022 1.022
50.000 1.021 1.021 1.020 1.020 1.019
50.125 1.018 1.018 1.017 1.017 1.016
50.250 1.016 1.015 1.014 1.014 1.013
50.375 1.013 1.012 1.012 1.011 1.010
50.500 1.010 1.009 1.009 1.008 1.008
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
88

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
50.625 1.007 1.007 1.006 1.005 1.005
50.750 1.004 1.004 1.003 1.003 1.002
50.875 1.001 1.001 1.000 1.000 0.999
51.000 0.999 0.998 0.997 0.997 0.996
51.125 0.996 0.995 0.995 0.994 0.994
51.250 0.993 0.992 0.992 0.991 0.991
51.375 0.990 0.990 0.989 0.989 0.988
51.500 0.987 0.987 0.986 0.986 0.985
51.625 0.985 0.984 0.983 0.983 0.982
51.750 0.982 0.981 0.981 0.980 0.980
51.875 0.979 0.978 0.978 0.977 0.977
52.000 0.976 0.976 0.975 0.975 0.974
52.125 0.974 0.973 0.972 0.972 0.971
52.250 0.971 0.970 0.970 0.969 0.969
52.375 0.968 0.967 0.967 0.966 0.966
52.500 0.965 0.965 0.964 0.964 0.963
52.625 0.962 0.962 0.961 0.961 0.960
52.750 0.960 0.959 0.959 0.958 0.958
52.875 0.957 0.956 0.956 0.955 0.955
53.000 0.954 0.954 0.953 0.953 0.952
53.125 0.952 0.951 0.950 0.950 0.949
53.250 0.949 0.948 0.948 0.947 0.947
53.375 0.946 0.946 0.945 0.944 0.944
53.500 0.943 0.943 0.942 0.942 0.941
53.625 0.941 0.940 0.940 0.939 0.938
53.750 0.938 0.937 0.937 0.936 0.936
53.875 0.935 0.935 0.934 0.934 0.933
54.000 0.933 0.932 0.931 0.931 0.930
54.125 0.930 0.929 0.929 0.928 0.928
54.250 0.927 0.927 0.926 0.926 0.925
54.375 0.924 0.924 0.923 0.923 0.922
54.500 0.922 0.921 0.921 0.920 0.920
54.625 0.919 0.919 0.918 0.918 0.917
54.750 0.916 0.916 0.915 0.915 0.914
54.875 0.914 0.913 0.913 0.912 0.912
55.000 0.911 0.911 0.910 0.910 0.909
55.125 0.908 0.908 0.907 0.907 0.906
55.250 0.906 0.905 0.905 0.904 0.904
55.375 0.903 0.903 0.902 0.902 0.901
55.500 0.901 0.900 0.899 0.899 0.898
55.625 0.898 0.897 0.897 0.896 0.896
55.750 0.895 0.895 0.894 0.894 0.893
55.875 0.893 0.892 0.892 0.891 0.891
56.000 0.890 0.890 0.889 0.888 0.888
56.125 0.887 0.887 0.886 0.886 0.885
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
89

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
56.250 0.885 0.884 0.884 0.883 0.883
56.375 0.882 0.882 0.881 0.881 0.880
56.500 0.880 0.879 0.879 0.878 0.878
56.625 0.877 0.876 0.876 0.875 0.875
56.750 0.874 0.874 0.873 0.873 0.872
56.875 0.872 0.871 0.871 0.870 0.870
57.000 0.869 0.869 0.868 0.868 0.867
57.125 0.867 0.866 0.866 0.865 0.865
57.250 0.864 0.864 0.863 0.863 0.862
57.375 0.862 0.861 0.860 0.860 0.859
57.500 0.859 0.858 0.858 0.857 0.857
57.625 0.856 0.856 0.855 0.855 0.854
57.750 0.854 0.853 0.853 0.852 0.852
57.875 0.851 0.851 0.850 0.850 0.849
58.000 0.849 0.848 0.848 0.847 0.847
58.125 0.846 0.846 0.845 0.845 0.844
58.250 0.844 0.843 0.843 0.842 0.842
58.375 0.841 0.841 0.840 0.840 0.839
58.500 0.839 0.838 0.838 0.837 0.837
58.625 0.836 0.836 0.835 0.835 0.834
58.750 0.834 0.833 0.833 0.832 0.832
58.875 0.831 0.831 0.830 0.830 0.829
59.000 0.829 0.828 0.828 0.827 0.827
59.125 0.826 0.826 0.825 0.825 0.824
59.250 0.824 0.823 0.823 0.822 0.822
59.375 0.821 0.821 0.820 0.820 0.819
59.500 0.819 0.818 0.818 0.817 0.817
59.625 0.816 0.816 0.815 0.815 0.814
59.750 0.814 0.813 0.813 0.812 0.812
59.875 0.811 0.811 0.810 0.810 0.809
60.000 0.809 0.808 0.808 0.807 0.807
60.125 0.806 0.806 0.805 0.805 0.804
60.250 0.804 0.803 0.803 0.802 0.802
60.375 0.801 0.801 0.800 0.800 0.799
60.500 0.799 0.798 0.798 0.797 0.797
60.625 0.796 0.796 0.795 0.795 0.794
60.750 0.794 0.794 0.793 0.793 0.792
60.875 0.792 0.791 0.791 0.790 0.790
61.000 0.789 0.789 0.788 0.788 0.787
61.125 0.787 0.786 0.786 0.785 0.785
61.250 0.784 0.784 0.783 0.783 0.782
61.375 0.782 0.782 0.781 0.781 0.780
61.500 0.780 0.779 0.779 0.778 0.778
61.625 0.777 0.777 0.776 0.776 0.775
61.750 0.775 0.774 0.774 0.773 0.773
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
90

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
61.875 0.773 0.772 0.772 0.771 0.771
62.000 0.770 0.770 0.769 0.769 0.768
62.125 0.768 0.767 0.767 0.766 0.766
62.250 0.765 0.765 0.765 0.764 0.764
62.375 0.763 0.763 0.762 0.762 0.761
62.500 0.761 0.760 0.760 0.759 0.759
62.625 0.759 0.758 0.758 0.757 0.757
62.750 0.756 0.756 0.755 0.755 0.754
62.875 0.754 0.753 0.753 0.753 0.752
63.000 0.752 0.751 0.751 0.750 0.750
63.125 0.749 0.749 0.748 0.748 0.748
63.250 0.747 0.747 0.746 0.746 0.745
63.375 0.745 0.744 0.744 0.743 0.743
63.500 0.743 0.742 0.742 0.741 0.741
63.625 0.740 0.740 0.739 0.739 0.738
63.750 0.738 0.738 0.737 0.737 0.736
63.875 0.736 0.735 0.735 0.734 0.734
64.000 0.734 0.733 0.733 0.732 0.732
64.125 0.731 0.731 0.730 0.730 0.730
64.250 0.729 0.729 0.728 0.728 0.727
64.375 0.727 0.726 0.726 0.726 0.725
64.500 0.725 0.724 0.724 0.723 0.723
64.625 0.722 0.722 0.722 0.721 0.721
64.750 0.720 0.720 0.719 0.719 0.719
64.875 0.718 0.718 0.717 0.717 0.716
65.000 0.716 0.715 0.715 0.715 0.714
65.125 0.714 0.713 0.713 0.712 0.712
65.250 0.712 0.711 0.711 0.710 0.710
65.375 0.709 0.709 0.708 0.708 0.708
65.500 0.707 0.707 0.706 0.706 0.705
65.625 0.705 0.705 0.704 0.704 0.703
65.750 0.703 0.702 0.702 0.702 0.701
65.875 0.701 0.700 0.700 0.699 0.699
66.000 0.699 0.698 0.698 0.697 0.697
66.125 0.697 0.696 0.696 0.695 0.695
66.250 0.694 0.694 0.694 0.693 0.693
66.375 0.692 0.692 0.691 0.691 0.691
66.500 0.690 0.690 0.689 0.689 0.688
66.625 0.688 0.688 0.687 0.687 0.686
66.750 0.686 0.686 0.685 0.685 0.684
66.875 0.684 0.683 0.683 0.683 0.682
67.000 0.682 0.681 0.681 0.681 0.680
67.125 0.680 0.679 0.679 0.679 0.678
67.250 0.678 0.677 0.677 0.676 0.676
67.375 0.676 0.675 0.675 0.674 0.674
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
91

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 1 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
67.500 0.674 0.673 0.673 0.672 0.672
67.625 0.672 0.671 0.671 0.670 0.670
67.750 0.669 0.669 0.669 0.668 0.668
67.875 0.667 0.667 0.667 0.666 0.666
68.000 0.665 0.665 0.665 0.664 0.664
68.125 0.663 0.663 0.663 0.662 0.662
68.250 0.661 0.661 0.661 0.660 0.660
68.375 0.659 0.659 0.659 0.658 0.658
68.500 0.657 0.657 0.657 0.656 0.656
68.625 0.655 0.655 0.655 0.654 0.654
68.750 0.653 0.653 0.653 0.652 0.652
68.875 0.651 0.651 0.651 0.650 0.650
69.000 0.649 0.649 0.649 0.648 0.648
69.125 0.647 0.647 0.647 0.646 0.646
69.250 0.645 0.645 0.645 0.644 0.644
69.375 0.643 0.643 0.643 0.642 0.642
69.500 0.642 0.641 0.641 0.640 0.640
69.625 0.640 0.639 0.639 0.638 0.638
69.750 0.638 0.637 0.637 0.636 0.636
69.875 0.636 0.635 0.635 0.635 0.634
70.000 0.634 0.633 0.633 0.633 0.632
70.125 0.632 0.631 0.631 0.631 0.630
70.250 0.630 0.630 0.629 0.629 0.628
70.375 0.628 0.628 0.627 0.627 0.626
70.500 0.626 0.626 0.625 0.625 0.625
70.625 0.624 0.624 0.623 0.623 0.623
70.750 0.622 0.622 0.622 0.621 0.621
70.875 0.620 0.620 0.620 0.619 0.619
71.000 0.619 0.618 0.618 0.617 0.617
71.125 0.617 0.616 0.616 0.615 0.615
71.250 0.615 0.614 0.614 0.614 0.613
71.375 0.613 0.613 0.612 0.612 0.611
71.500 0.611 0.611 0.610 0.610 0.610
71.625 0.609 0.609 0.608 0.608 0.608
71.750 0.607 0.607 0.607 0.606 0.606
71.875 0.605 0.605 0.605 0.604 0.604
72.000 0.604 (N/A) (N/A) (N/A) (N/A)
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
92

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
0.000 0.000 0.000 0.000 0.000 0.000
0.125 0.000 0.000 0.000 0.000 0.000
0.250 0.000 0.000 0.000 0.000 0.000
0.375 0.000 0.000 0.000 0.000 0.000
0.500 0.000 0.000 0.000 0.000 0.000
0.625 0.000 0.000 0.000 0.000 0.000
0.750 0.000 0.000 0.000 0.000 0.000
0.875 0.000 0.000 0.000 0.000 0.000
1.000 0.000 0.000 0.000 0.000 0.000
1.125 0.000 0.000 0.000 0.000 0.000
1.250 0.000 0.000 0.000 0.000 0.000
1.375 0.000 0.000 0.000 0.000 0.000
1.500 0.000 0.000 0.000 0.000 0.000
1.625 0.000 0.000 0.000 0.000 0.000
1.750 0.000 0.000 0.000 0.000 0.000
1.875 0.000 0.000 0.000 0.000 0.000
2.000 0.000 0.000 0.000 0.000 0.000
2.125 0.000 0.000 0.000 0.000 0.000
2.250 0.000 0.000 0.000 0.000 0.000
2.375 0.000 0.000 0.000 0.000 0.000
2.500 0.000 0.000 0.000 0.000 0.000
2.625 0.000 0.000 0.000 0.000 0.000
2.750 0.000 0.000 0.000 0.000 0.000
2.875 0.000 0.000 0.000 0.000 0.000
3.000 0.000 0.000 0.000 0.000 0.000
3.125 0.000 0.000 0.000 0.000 0.000
3.250 0.000 0.000 0.000 0.000 0.000
3.375 0.000 0.000 0.000 0.000 0.000
3.500 0.000 0.000 0.000 0.000 0.000
3.625 0.000 0.000 0.000 0.000 0.000
3.750 0.000 0.000 0.000 0.000 0.000
3.875 0.000 0.000 0.000 0.000 0.000
4.000 0.000 0.000 0.000 0.000 0.000
4.125 0.000 0.000 0.000 0.000 0.000
4.250 0.000 0.000 0.000 0.000 0.000
4.375 0.000 0.000 0.000 0.000 0.000
4.500 0.000 0.000 0.000 0.000 0.000
4.625 0.000 0.000 0.000 0.000 0.000
4.750 0.000 0.000 0.000 0.000 0.000
4.875 0.000 0.000 0.000 0.000 0.000
5.000 0.000 0.000 0.000 0.000 0.000
5.125 0.000 0.000 0.000 0.000 0.000
5.250 0.000 0.000 0.000 0.000 0.000
5.375 0.000 0.000 0.000 0.000 0.000
5.500 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
93

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
5.625 0.000 0.000 0.000 0.000 0.000
5.750 0.000 0.000 0.000 0.000 0.000
5.875 0.000 0.000 0.000 0.000 0.000
6.000 0.000 0.000 0.000 0.000 0.000
6.125 0.000 0.000 0.000 0.000 0.000
6.250 0.000 0.000 0.000 0.000 0.000
6.375 0.000 0.000 0.000 0.000 0.000
6.500 0.000 0.000 0.000 0.000 0.000
6.625 0.000 0.000 0.000 0.000 0.000
6.750 0.000 0.000 0.000 0.000 0.000
6.875 0.000 0.000 0.000 0.000 0.000
7.000 0.000 0.000 0.000 0.000 0.000
7.125 0.000 0.000 0.000 0.000 0.000
7.250 0.000 0.000 0.000 0.000 0.000
7.375 0.000 0.000 0.000 0.000 0.000
7.500 0.000 0.000 0.000 0.000 0.000
7.625 0.000 0.000 0.000 0.000 0.000
7.750 0.000 0.000 0.000 0.000 0.000
7.875 0.000 0.000 0.000 0.000 0.000
8.000 0.000 0.000 0.000 0.000 0.000
8.125 0.000 0.000 0.000 0.000 0.000
8.250 0.000 0.000 0.000 0.000 0.000
8.375 0.000 0.000 0.000 0.000 0.000
8.500 0.000 0.000 0.000 0.000 0.000
8.625 0.000 0.000 0.000 0.000 0.000
8.750 0.000 0.000 0.000 0.000 0.000
8.875 0.000 0.000 0.000 0.000 0.000
9.000 0.000 0.000 0.000 0.000 0.000
9.125 0.000 0.000 0.000 0.000 0.000
9.250 0.000 0.000 0.000 0.000 0.000
9.375 0.000 0.000 0.000 0.000 0.000
9.500 0.000 0.000 0.000 0.000 0.000
9.625 0.000 0.000 0.000 0.000 0.000
9.750 0.000 0.000 0.000 0.000 0.000
9.875 0.000 0.000 0.000 0.000 0.000
10.000 0.000 0.000 0.000 0.000 0.000
10.125 0.000 0.000 0.000 0.000 0.000
10.250 0.000 0.000 0.000 0.000 0.000
10.375 0.000 0.000 0.000 0.000 0.000
10.500 0.000 0.000 0.000 0.000 0.000
10.625 0.000 0.000 0.000 0.000 0.000
10.750 0.000 0.000 0.000 0.000 0.000
10.875 0.000 0.000 0.000 0.000 0.000
11.000 0.000 0.000 0.000 0.000 0.000
11.125 0.000 0.000 0.000 0.000 0.001
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
94

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
11.250 0.001 0.001 0.001 0.001 0.001
11.375 0.001 0.001 0.002 0.002 0.002
11.500 0.002 0.002 0.003 0.003 0.004
11.625 0.005 0.006 0.007 0.009 0.011
11.750 0.014 0.017 0.022 0.027 0.035
11.875 0.045 0.057 0.072 0.086 0.101
12.000 0.114 0.128 0.139 0.147 0.152
12.125 0.155 0.158 0.160 0.162 0.164
12.250 0.166 0.167 0.169 0.170 0.172
12.375 0.173 0.174 0.175 0.175 0.176
12.500 0.177 0.177 0.177 0.178 0.178
12.625 0.178 0.178 0.179 0.179 0.179
12.750 0.179 0.179 0.179 0.179 0.179
12.875 0.179 0.179 0.179 0.179 0.179
13.000 0.178 0.178 0.178 0.178 0.178
13.125 0.178 0.177 0.177 0.177 0.177
13.250 0.177 0.176 0.176 0.176 0.176
13.375 0.175 0.175 0.175 0.175 0.174
13.500 0.174 0.174 0.173 0.173 0.173
13.625 0.172 0.172 0.172 0.172 0.171
13.750 0.171 0.171 0.170 0.170 0.170
13.875 0.169 0.169 0.169 0.168 0.168
14.000 0.168 0.167 0.167 0.167 0.166
14.125 0.166 0.166 0.165 0.165 0.165
14.250 0.164 0.164 0.164 0.164 0.163
14.375 0.163 0.163 0.162 0.162 0.162
14.500 0.162 0.161 0.161 0.161 0.161
14.625 0.160 0.160 0.160 0.160 0.159
14.750 0.159 0.159 0.159 0.158 0.158
14.875 0.158 0.158 0.157 0.157 0.157
15.000 0.157 0.156 0.156 0.156 0.156
15.125 0.155 0.155 0.155 0.154 0.154
15.250 0.154 0.154 0.153 0.153 0.153
15.375 0.152 0.152 0.152 0.151 0.151
15.500 0.151 0.150 0.150 0.150 0.149
15.625 0.149 0.149 0.148 0.148 0.148
15.750 0.147 0.147 0.147 0.146 0.146
15.875 0.146 0.145 0.145 0.145 0.144
16.000 0.144 0.144 0.143 0.143 0.142
16.125 0.142 0.142 0.141 0.141 0.140
16.250 0.140 0.140 0.139 0.139 0.139
16.375 0.138 0.138 0.137 0.137 0.137
16.500 0.136 0.136 0.136 0.135 0.135
16.625 0.134 0.134 0.134 0.133 0.133
16.750 0.132 0.132 0.132 0.131 0.131
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
95

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
16.875 0.130 0.130 0.130 0.129 0.129
17.000 0.129 0.128 0.128 0.127 0.127
17.125 0.127 0.126 0.126 0.125 0.125
17.250 0.125 0.124 0.124 0.123 0.123
17.375 0.123 0.122 0.122 0.121 0.121
17.500 0.121 0.120 0.120 0.119 0.119
17.625 0.119 0.118 0.118 0.117 0.117
17.750 0.117 0.116 0.116 0.115 0.115
17.875 0.114 0.114 0.114 0.113 0.113
18.000 0.112 0.112 0.112 0.111 0.111
18.125 0.110 0.110 0.110 0.109 0.109
18.250 0.108 0.108 0.107 0.107 0.107
18.375 0.106 0.106 0.105 0.105 0.105
18.500 0.104 0.104 0.103 0.103 0.102
18.625 0.102 0.102 0.101 0.101 0.100
18.750 0.100 0.099 0.099 0.099 0.098
18.875 0.098 0.097 0.097 0.097 0.096
19.000 0.096 0.095 0.095 0.094 0.094
19.125 0.094 0.093 0.093 0.092 0.092
19.250 0.091 0.091 0.090 0.090 0.090
19.375 0.089 0.089 0.088 0.088 0.087
19.500 0.087 0.087 0.086 0.086 0.085
19.625 0.085 0.084 0.084 0.083 0.083
19.750 0.083 0.082 0.082 0.081 0.081
19.875 0.080 0.080 0.079 0.079 0.079
20.000 0.078 0.078 0.077 0.077 0.076
20.125 0.076 0.075 0.075 0.075 0.074
20.250 0.074 0.073 0.073 0.072 0.072
20.375 0.071 0.071 0.071 0.070 0.070
20.500 0.069 0.069 0.068 0.068 0.067
20.625 0.067 0.067 0.066 0.066 0.065
20.750 0.065 0.064 0.064 0.064 0.063
20.875 0.063 0.062 0.062 0.061 0.061
21.000 0.061 0.060 0.060 0.059 0.059
21.125 0.058 0.058 0.058 0.057 0.057
21.250 0.056 0.056 0.056 0.055 0.055
21.375 0.054 0.054 0.053 0.053 0.053
21.500 0.052 0.052 0.051 0.051 0.051
21.625 0.050 0.050 0.049 0.049 0.049
21.750 0.048 0.048 0.047 0.047 0.047
21.875 0.046 0.046 0.045 0.045 0.045
22.000 0.044 0.044 0.043 0.043 0.043
22.125 0.042 0.042 0.041 0.041 0.041
22.250 0.040 0.040 0.039 0.039 0.039
22.375 0.038 0.038 0.037 0.037 0.037
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
96

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
22.500 0.036 0.036 0.036 0.035 0.035
22.625 0.034 0.034 0.034 0.033 0.033
22.750 0.033 0.032 0.032 0.031 0.031
22.875 0.031 0.030 0.030 0.029 0.029
23.000 0.029 0.028 0.028 0.028 0.027
23.125 0.027 0.027 0.026 0.026 0.025
23.250 0.025 0.025 0.024 0.024 0.024
23.375 0.023 0.023 0.023 0.022 0.022
23.500 0.021 0.021 0.021 0.020 0.020
23.625 0.020 0.019 0.019 0.019 0.018
23.750 0.018 0.017 0.017 0.017 0.016
23.875 0.016 0.016 0.015 0.015 0.015
24.000 0.014 0.014 0.014 0.013 0.013
24.125 0.012 0.012 0.012 0.011 0.011
24.250 0.010 0.010 0.010 0.009 0.009
24.375 0.009 0.008 0.008 0.008 0.007
24.500 0.007 0.007 0.007 0.006 0.006
24.625 0.006 0.006 0.005 0.005 0.005
24.750 0.005 0.005 0.004 0.004 0.004
24.875 0.004 0.004 0.004 0.004 0.003
25.000 0.003 0.003 0.003 0.003 0.003
25.125 0.003 0.003 0.003 0.002 0.002
25.250 0.002 0.002 0.002 0.002 0.002
25.375 0.002 0.002 0.002 0.002 0.002
25.500 0.002 0.001 0.001 0.001 0.001
25.625 0.001 0.001 0.001 0.001 0.001
25.750 0.001 0.001 0.001 0.001 0.001
25.875 0.001 0.001 0.001 0.001 0.001
26.000 0.001 0.001 0.001 0.001 0.001
26.125 0.001 0.001 0.001 0.001 0.001
26.250 0.001 0.000 0.000 0.000 0.000
26.375 0.000 0.000 0.000 0.000 0.000
26.500 0.000 0.000 0.000 0.000 0.000
26.625 0.000 0.000 0.000 0.000 0.000
26.750 0.000 0.000 0.000 0.000 0.000
26.875 0.000 0.000 0.000 0.000 0.000
27.000 0.000 0.000 0.000 0.000 0.000
27.125 0.000 0.000 0.000 0.000 0.000
27.250 0.000 0.000 0.000 0.000 0.000
27.375 0.000 0.000 0.000 0.000 0.000
27.500 0.000 0.000 0.000 0.000 0.000
27.625 0.000 0.000 0.000 0.000 0.000
27.750 0.000 0.000 0.000 0.000 0.000
27.875 0.000 0.000 0.000 0.000 0.000
28.000 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
97

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
28.125 0.000 0.000 0.000 0.000 0.000
28.250 0.000 0.000 0.000 0.000 0.000
28.375 0.000 0.000 0.000 0.000 0.000
28.500 0.000 0.000 0.000 0.000 0.000
28.625 0.000 0.000 0.000 0.000 0.000
28.750 0.000 0.000 0.000 0.000 0.000
28.875 0.000 0.000 0.000 0.000 0.000
29.000 0.000 0.000 0.000 0.000 0.000
29.125 0.000 0.000 0.000 0.000 0.000
29.250 0.000 0.000 0.000 0.000 0.000
29.375 0.000 0.000 0.000 0.000 0.000
29.500 0.000 0.000 0.000 0.000 0.000
29.625 0.000 0.000 0.000 0.000 0.000
29.750 0.000 0.000 0.000 0.000 0.000
29.875 0.000 0.000 0.000 0.000 0.000
30.000 0.000 0.000 0.000 0.000 0.000
30.125 0.000 0.000 0.000 0.000 0.000
30.250 0.000 0.000 0.000 0.000 0.000
30.375 0.000 0.000 0.000 0.000 0.000
30.500 0.000 0.000 0.000 0.000 0.000
30.625 0.000 0.000 0.000 0.000 0.000
30.750 0.000 0.000 0.000 0.000 0.000
30.875 0.000 0.000 0.000 0.000 0.000
31.000 0.000 0.000 0.000 0.000 0.000
31.125 0.000 0.000 0.000 0.000 0.000
31.250 0.000 0.000 0.000 0.000 0.000
31.375 0.000 0.000 0.000 0.000 0.000
31.500 0.000 0.000 0.000 0.000 0.000
31.625 0.000 0.000 0.000 0.000 0.000
31.750 0.000 0.000 0.000 0.000 0.000
31.875 0.000 0.000 0.000 0.000 0.000
32.000 0.000 0.000 0.000 0.000 0.000
32.125 0.000 0.000 0.000 0.000 0.000
32.250 0.000 0.000 0.000 0.000 0.000
32.375 0.000 0.000 0.000 0.000 0.000
32.500 0.000 0.000 0.000 0.000 0.000
32.625 0.000 0.000 0.000 0.000 0.000
32.750 0.000 0.000 0.000 0.000 0.000
32.875 0.000 0.000 0.000 0.000 0.000
33.000 0.000 0.000 0.000 0.000 0.000
33.125 0.000 0.000 0.000 0.000 0.000
33.250 0.000 0.000 0.000 0.000 0.000
33.375 0.000 0.000 0.000 0.000 0.000
33.500 0.000 0.000 0.000 0.000 0.000
33.625 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
98

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
33.750 0.000 0.000 0.000 0.000 0.000
33.875 0.000 0.000 0.000 0.000 0.000
34.000 0.000 0.000 0.000 0.000 0.000
34.125 0.000 0.000 0.000 0.000 0.000
34.250 0.000 0.000 0.000 0.000 0.000
34.375 0.000 0.000 0.000 0.000 0.000
34.500 0.000 0.000 0.000 0.000 0.000
34.625 0.000 0.000 0.000 0.000 0.000
34.750 0.000 0.000 0.000 0.000 0.000
34.875 0.000 0.000 0.000 0.000 0.000
35.000 0.000 0.000 0.000 0.000 0.000
35.125 0.000 0.000 0.000 0.000 0.000
35.250 0.000 0.000 0.000 0.000 0.000
35.375 0.000 0.000 0.000 0.000 0.000
35.500 0.000 0.000 0.000 0.000 0.000
35.625 0.000 0.000 0.000 0.000 0.000
35.750 0.000 0.000 0.000 0.000 0.000
35.875 0.000 0.000 0.000 0.000 0.000
36.000 0.000 0.000 0.000 0.000 0.000
36.125 0.000 0.000 0.000 0.000 0.000
36.250 0.000 0.000 0.000 0.000 0.000
36.375 0.000 0.000 0.000 0.000 0.000
36.500 0.000 0.000 0.000 0.000 0.000
36.625 0.000 0.000 0.000 0.000 0.000
36.750 0.000 0.000 0.000 0.000 0.000
36.875 0.000 0.000 0.000 0.000 0.000
37.000 0.000 0.000 0.000 0.000 0.000
37.125 0.000 0.000 0.000 0.000 0.000
37.250 0.000 0.000 0.000 0.000 0.000
37.375 0.000 0.000 0.000 0.000 0.000
37.500 0.000 0.000 0.000 0.000 0.000
37.625 0.000 0.000 0.000 0.000 0.000
37.750 0.000 0.000 0.000 0.000 0.000
37.875 0.000 0.000 0.000 0.000 0.000
38.000 0.000 0.000 0.000 0.000 0.000
38.125 0.000 0.000 0.000 0.000 0.000
38.250 0.000 0.000 0.000 0.000 0.000
38.375 0.000 0.000 0.000 0.000 0.000
38.500 0.000 0.000 0.000 0.000 0.000
38.625 0.000 0.000 0.000 0.000 0.000
38.750 0.000 0.000 0.000 0.000 0.000
38.875 0.000 0.000 0.000 0.000 0.000
39.000 0.000 0.000 0.000 0.000 0.000
39.125 0.000 0.000 0.000 0.000 0.000
39.250 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
99

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
39.375 0.000 0.000 0.000 0.000 0.000
39.500 0.000 0.000 0.000 0.000 0.000
39.625 0.000 0.000 0.000 0.000 0.000
39.750 0.000 0.000 0.000 0.000 0.000
39.875 0.000 0.000 0.000 0.000 0.000
40.000 0.000 0.000 0.000 0.000 0.000
40.125 0.000 0.000 0.000 0.000 0.000
40.250 0.000 0.000 0.000 0.000 0.000
40.375 0.000 0.000 0.000 0.000 0.000
40.500 0.000 0.000 0.000 0.000 0.000
40.625 0.000 0.000 0.000 0.000 0.000
40.750 0.000 0.000 0.000 0.000 0.000
40.875 0.000 0.000 0.000 0.000 0.000
41.000 0.000 0.000 0.000 0.000 0.000
41.125 0.000 0.000 0.000 0.000 0.000
41.250 0.000 0.000 0.000 0.000 0.000
41.375 0.000 0.000 0.000 0.000 0.000
41.500 0.000 0.000 0.000 0.000 0.000
41.625 0.000 0.000 0.000 0.000 0.000
41.750 0.000 0.000 0.000 0.000 0.000
41.875 0.000 0.000 0.000 0.000 0.000
42.000 0.000 0.000 0.000 0.000 0.000
42.125 0.000 0.000 0.000 0.000 0.000
42.250 0.000 0.000 0.000 0.000 0.000
42.375 0.000 0.000 0.000 0.000 0.000
42.500 0.000 0.000 0.000 0.000 0.000
42.625 0.000 0.000 0.000 0.000 0.000
42.750 0.000 0.000 0.000 0.000 0.000
42.875 0.000 0.000 0.000 0.000 0.000
43.000 0.000 0.000 0.000 0.000 0.000
43.125 0.000 0.000 0.000 0.000 0.000
43.250 0.000 0.000 0.000 0.000 0.000
43.375 0.000 0.000 0.000 0.000 0.000
43.500 0.000 0.000 0.000 0.000 0.000
43.625 0.000 0.000 0.000 0.000 0.000
43.750 0.000 0.000 0.000 0.000 0.000
43.875 0.000 0.000 0.000 0.000 0.000
44.000 0.000 0.000 0.000 0.000 0.000
44.125 0.000 0.000 0.000 0.000 0.000
44.250 0.000 0.000 0.000 0.000 0.000
44.375 0.000 0.000 0.000 0.000 0.000
44.500 0.000 0.000 0.000 0.000 0.000
44.625 0.000 0.000 0.000 0.000 0.000
44.750 0.000 0.000 0.000 0.000 0.000
44.875 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
100

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
45.000 0.000 0.000 0.000 0.000 0.000
45.125 0.000 0.000 0.000 0.000 0.000
45.250 0.000 0.000 0.000 0.000 0.000
45.375 0.000 0.000 0.000 0.000 0.000
45.500 0.000 0.000 0.000 0.000 0.000
45.625 0.000 0.000 0.000 0.000 0.000
45.750 0.000 0.000 0.000 0.000 0.000
45.875 0.000 0.000 0.000 0.000 0.000
46.000 0.000 0.000 0.000 0.000 0.000
46.125 0.000 0.000 0.000 0.000 0.000
46.250 0.000 0.000 0.000 0.000 0.000
46.375 0.000 0.000 0.000 0.000 0.000
46.500 0.000 0.000 0.000 0.000 0.000
46.625 0.000 0.000 0.000 0.000 0.000
46.750 0.000 0.000 0.000 0.000 0.000
46.875 0.000 0.000 0.000 0.000 0.000
47.000 0.000 0.000 0.000 0.000 0.000
47.125 0.000 0.000 0.000 0.000 0.000
47.250 0.000 0.000 0.000 0.000 0.000
47.375 0.000 0.000 0.000 0.000 0.000
47.500 0.000 0.000 0.000 0.000 0.000
47.625 0.000 0.000 0.000 0.000 0.000
47.750 0.000 0.000 0.000 0.000 0.000
47.875 0.000 0.000 0.000 0.000 0.000
48.000 0.000 0.000 0.000 0.000 0.000
48.125 0.000 0.000 0.000 0.000 0.000
48.250 0.000 0.000 0.000 0.000 0.000
48.375 0.000 0.000 0.000 0.000 0.000
48.500 0.000 0.000 0.000 0.000 0.000
48.625 0.000 0.000 0.000 0.000 0.000
48.750 0.000 0.000 0.000 0.000 0.000
48.875 0.000 0.000 0.000 0.000 0.000
49.000 0.000 0.000 0.000 0.000 0.000
49.125 0.000 0.000 0.000 0.000 0.000
49.250 0.000 0.000 0.000 0.000 0.000
49.375 0.000 0.000 0.000 0.000 0.000
49.500 0.000 0.000 0.000 0.000 0.000
49.625 0.000 0.000 0.000 0.000 0.000
49.750 0.000 0.000 0.000 0.000 0.000
49.875 0.000 0.000 0.000 0.000 0.000
50.000 0.000 0.000 0.000 0.000 0.000
50.125 0.000 0.000 0.000 0.000 0.000
50.250 0.000 0.000 0.000 0.000 0.000
50.375 0.000 0.000 0.000 0.000 0.000
50.500 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
101

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
50.625 0.000 0.000 0.000 0.000 0.000
50.750 0.000 0.000 0.000 0.000 0.000
50.875 0.000 0.000 0.000 0.000 0.000
51.000 0.000 0.000 0.000 0.000 0.000
51.125 0.000 0.000 0.000 0.000 0.000
51.250 0.000 0.000 0.000 0.000 0.000
51.375 0.000 0.000 0.000 0.000 0.000
51.500 0.000 0.000 0.000 0.000 0.000
51.625 0.000 0.000 0.000 0.000 0.000
51.750 0.000 0.000 0.000 0.000 0.000
51.875 0.000 0.000 0.000 0.000 0.000
52.000 0.000 0.000 0.000 0.000 0.000
52.125 0.000 0.000 0.000 0.000 0.000
52.250 0.000 0.000 0.000 0.000 0.000
52.375 0.000 0.000 0.000 0.000 0.000
52.500 0.000 0.000 0.000 0.000 0.000
52.625 0.000 0.000 0.000 0.000 0.000
52.750 0.000 0.000 0.000 0.000 0.000
52.875 0.000 0.000 0.000 0.000 0.000
53.000 0.000 0.000 0.000 0.000 0.000
53.125 0.000 0.000 0.000 0.000 0.000
53.250 0.000 0.000 0.000 0.000 0.000
53.375 0.000 0.000 0.000 0.000 0.000
53.500 0.000 0.000 0.000 0.000 0.000
53.625 0.000 0.000 0.000 0.000 0.000
53.750 0.000 0.000 0.000 0.000 0.000
53.875 0.000 0.000 0.000 0.000 0.000
54.000 0.000 0.000 0.000 0.000 0.000
54.125 0.000 0.000 0.000 0.000 0.000
54.250 0.000 0.000 0.000 0.000 0.000
54.375 0.000 0.000 0.000 0.000 0.000
54.500 0.000 0.000 0.000 0.000 0.000
54.625 0.000 0.000 0.000 0.000 0.000
54.750 0.000 0.000 0.000 0.000 0.000
54.875 0.000 0.000 0.000 0.000 0.000
55.000 0.000 0.000 0.000 0.000 0.000
55.125 0.000 0.000 0.000 0.000 0.000
55.250 0.000 0.000 0.000 0.000 0.000
55.375 0.000 0.000 0.000 0.000 0.000
55.500 0.000 0.000 0.000 0.000 0.000
55.625 0.000 0.000 0.000 0.000 0.000
55.750 0.000 0.000 0.000 0.000 0.000
55.875 0.000 0.000 0.000 0.000 0.000
56.000 0.000 0.000 0.000 0.000 0.000
56.125 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
102

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
56.250 0.000 0.000 0.000 0.000 0.000
56.375 0.000 0.000 0.000 0.000 0.000
56.500 0.000 0.000 0.000 0.000 0.000
56.625 0.000 0.000 0.000 0.000 0.000
56.750 0.000 0.000 0.000 0.000 0.000
56.875 0.000 0.000 0.000 0.000 0.000
57.000 0.000 0.000 0.000 0.000 0.000
57.125 0.000 0.000 0.000 0.000 0.000
57.250 0.000 0.000 0.000 0.000 0.000
57.375 0.000 0.000 0.000 0.000 0.000
57.500 0.000 0.000 0.000 0.000 0.000
57.625 0.000 0.000 0.000 0.000 0.000
57.750 0.000 0.000 0.000 0.000 0.000
57.875 0.000 0.000 0.000 0.000 0.000
58.000 0.000 0.000 0.000 0.000 0.000
58.125 0.000 0.000 0.000 0.000 0.000
58.250 0.000 0.000 0.000 0.000 0.000
58.375 0.000 0.000 0.000 0.000 0.000
58.500 0.000 0.000 0.000 0.000 0.000
58.625 0.000 0.000 0.000 0.000 0.000
58.750 0.000 0.000 0.000 0.000 0.000
58.875 0.000 0.000 0.000 0.000 0.000
59.000 0.000 0.000 0.000 0.000 0.000
59.125 0.000 0.000 0.000 0.000 0.000
59.250 0.000 0.000 0.000 0.000 0.000
59.375 0.000 0.000 0.000 0.000 0.000
59.500 0.000 0.000 0.000 0.000 0.000
59.625 0.000 0.000 0.000 0.000 0.000
59.750 0.000 0.000 0.000 0.000 0.000
59.875 0.000 0.000 0.000 0.000 0.000
60.000 0.000 0.000 0.000 0.000 0.000
60.125 0.000 0.000 0.000 0.000 0.000
60.250 0.000 0.000 0.000 0.000 0.000
60.375 0.000 0.000 0.000 0.000 0.000
60.500 0.000 0.000 0.000 0.000 0.000
60.625 0.000 0.000 0.000 0.000 0.000
60.750 0.000 0.000 0.000 0.000 0.000
60.875 0.000 0.000 0.000 0.000 0.000
61.000 0.000 0.000 0.000 0.000 0.000
61.125 0.000 0.000 0.000 0.000 0.000
61.250 0.000 0.000 0.000 0.000 0.000
61.375 0.000 0.000 0.000 0.000 0.000
61.500 0.000 0.000 0.000 0.000 0.000
61.625 0.000 0.000 0.000 0.000 0.000
61.750 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
103

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
61.875 0.000 0.000 0.000 0.000 0.000
62.000 0.000 0.000 0.000 0.000 0.000
62.125 0.000 0.000 0.000 0.000 0.000
62.250 0.000 0.000 0.000 0.000 0.000
62.375 0.000 0.000 0.000 0.000 0.000
62.500 0.000 0.000 0.000 0.000 0.000
62.625 0.000 0.000 0.000 0.000 0.000
62.750 0.000 0.000 0.000 0.000 0.000
62.875 0.000 0.000 0.000 0.000 0.000
63.000 0.000 0.000 0.000 0.000 0.000
63.125 0.000 0.000 0.000 0.000 0.000
63.250 0.000 0.000 0.000 0.000 0.000
63.375 0.000 0.000 0.000 0.000 0.000
63.500 0.000 0.000 0.000 0.000 0.000
63.625 0.000 0.000 0.000 0.000 0.000
63.750 0.000 0.000 0.000 0.000 0.000
63.875 0.000 0.000 0.000 0.000 0.000
64.000 0.000 0.000 0.000 0.000 0.000
64.125 0.000 0.000 0.000 0.000 0.000
64.250 0.000 0.000 0.000 0.000 0.000
64.375 0.000 0.000 0.000 0.000 0.000
64.500 0.000 0.000 0.000 0.000 0.000
64.625 0.000 0.000 0.000 0.000 0.000
64.750 0.000 0.000 0.000 0.000 0.000
64.875 0.000 0.000 0.000 0.000 0.000
65.000 0.000 0.000 0.000 0.000 0.000
65.125 0.000 0.000 0.000 0.000 0.000
65.250 0.000 0.000 0.000 0.000 0.000
65.375 0.000 0.000 0.000 0.000 0.000
65.500 0.000 0.000 0.000 0.000 0.000
65.625 0.000 0.000 0.000 0.000 0.000
65.750 0.000 0.000 0.000 0.000 0.000
65.875 0.000 0.000 0.000 0.000 0.000
66.000 0.000 0.000 0.000 0.000 0.000
66.125 0.000 0.000 0.000 0.000 0.000
66.250 0.000 0.000 0.000 0.000 0.000
66.375 0.000 0.000 0.000 0.000 0.000
66.500 0.000 0.000 0.000 0.000 0.000
66.625 0.000 0.000 0.000 0.000 0.000
66.750 0.000 0.000 0.000 0.000 0.000
66.875 0.000 0.000 0.000 0.000 0.000
67.000 0.000 0.000 0.000 0.000 0.000
67.125 0.000 0.000 0.000 0.000 0.000
67.250 0.000 0.000 0.000 0.000 0.000
67.375 0.000 0.000 0.000 0.000 0.000
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
104

Subsection: Time vs. Volume Return Event: 1 years
Label: BMP 2 Storm Event: SCS Type II (2.92 in)
Time vs. Volume (ac-ft)
Output Time increment = 0.025 hours
Time on left represents time for first value in each row.
Time Volume Volume Volume Volume Volume
(hours) (ac-ft) (ac-ft) (ac-ft) (ac-ft) (ac-ft)
67.500 0.000 0.000 0.000 0.000 0.000
67.625 0.000 0.000 0.000 0.000 0.000
67.750 0.000 0.000 0.000 0.000 0.000
67.875 0.000 0.000 0.000 0.000 0.000
68.000 0.000 0.000 0.000 0.000 0.000
68.125 0.000 0.000 0.000 0.000 0.000
68.250 0.000 0.000 0.000 0.000 0.000
68.375 0.000 0.000 0.000 0.000 0.000
68.500 0.000 0.000 0.000 0.000 0.000
68.625 0.000 0.000 0.000 0.000 0.000
68.750 0.000 0.000 0.000 0.000 0.000
68.875 0.000 0.000 0.000 0.000 0.000
69.000 0.000 0.000 0.000 0.000 0.000
69.125 0.000 0.000 0.000 0.000 0.000
69.250 0.000 0.000 0.000 0.000 0.000
69.375 0.000 0.000 0.000 0.000 0.000
69.500 0.000 0.000 0.000 0.000 0.000
69.625 0.000 0.000 0.000 0.000 0.000
69.750 0.000 0.000 0.000 0.000 0.000
69.875 0.000 0.000 0.000 0.000 0.000
70.000 0.000 0.000 0.000 0.000 0.000
70.125 0.000 0.000 0.000 0.000 0.000
70.250 0.000 0.000 0.000 0.000 0.000
70.375 0.000 0.000 0.000 0.000 0.000
70.500 0.000 0.000 0.000 0.000 0.000
70.625 0.000 0.000 0.000 0.000 0.000
70.750 0.000 0.000 0.000 0.000 0.000
70.875 0.000 0.000 0.000 0.000 0.000
71.000 0.000 0.000 0.000 0.000 0.000
71.125 0.000 0.000 0.000 0.000 0.000
71.250 0.000 0.000 0.000 0.000 0.000
71.375 0.000 0.000 0.000 0.000 0.000
71.500 0.000 0.000 0.000 0.000 0.000
71.625 0.000 0.000 0.000 0.000 0.000
71.750 0.000 0.000 0.000 0.000 0.000
71.875 0.000 0.000 0.000 0.000 0.000
72.000 0.000 (N/A) (N/A) (N/A) (N/A)
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
105

Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
Requested Pond Water Surface Elevations
Minimum (Headwater) 636.50 ft
Increment(Headwater) 0.50 ft
Maximum (Headwater) 641.00 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall El E2
(ft) (ft)
Orifice-Circular 4"Orifice Forward Dual 24" 636.50 641.00
Outlet
Culverts
Rectangular Weir 18"Weir Forward Dual 24" 637.37 641.00
Outlet
Culverts
Rectangular Weir 6x9 Riser Forward Dual 24" 638.00 641.00
Outlet Box Outlet
Culverts
Culvert-Circular Dual 24" Forward TW 633.49 641.00
Outlet
Culverts
Rectangular Weir Emergency Forward TW 639.83 641.00
Overflow
Tailwater Settings Tailwater (N/A) (N/A)
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
106

Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
Structure ID: Emergency Overflow
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 639.83 ft
Weir Length 30.00 ft
Weir Coefficient 3.10(ft^0.5)/s
Structure ID: 6x9 Riser Outlet Box
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 638.00 ft
Weir Length 28.50 ft
Weir Coefficient 3.33 (ft^0.5)/s
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
107

Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
Structure ID: Dual 24"Outlet Culverts
Structure Type: Culvert-Circular
Number of Barrels 2
Diameter 24.0 in
Length 57.00 ft
Length (Computed Barrel) 57.00 ft
Slope(Computed) 0.005 ft/ft
Outlet Control Data
Manning's n 0.012
Ke 0.500
Kb 0.011
Kr 0.500
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) 1.158
T2 ratio(HW/D) 1.304
Slope Correction Factor -0.500
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...
T1 Elevation 635.81 ft T1 Flow 15.55 ft3/s
T2 Elevation 636.10 ft T2 Flow 17.77 ft3/s
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
108

Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
Structure ID: 4"Orifice
Structure Type: Orifice-Circular
Number of Openings 1
Elevation 636.50 ft
Orifice Diameter 4.0 in
Orifice Coefficient 0.600
Structure ID: 18"Weir
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 637.37 ft
Weir Length 1.50 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type Free Outfall
Convergence Tolerances
Maximum Iterations 50
Tailwater Tolerance 0.01 ft
(Minimum)
Tailwater Tolerance 0.50 ft
(Maximum)
Headwater Tolerance 0.01 ft
(Minimum)
Headwater Tolerance 0.50 ft
(Maximum)
Flow Tolerance(Minimum) 0.010 ft3/s
Flow Tolerance(Maximum) 10.000 ft3/s
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
109

Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = Emergency Overflow (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Tailwater (Pond Outfall)
Water Surface Flow Tailwater Elevation Convergence Error Computation Messages
Elevation (ft3/s) (ft) (ft)
(ft)
636.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 (N/A) 0.00
637.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.83 0.00 (N/A) 0.00 WS below an invert; no
flow.
640.00 6.52 (N/A) 0.00 H=.17; Htw=.00;
Qfree=6.52;
640.50 51.00 (N/A) 0.00 H=.67; Htw=.00;
Qfree=51.00;
641.00 117.70 (N/A) 0.00 H=1.17;Htw=.00;
Qfree=117.70;
20155-Pondpack Model.ppc
1/25/2024 The Isaacs Group
110

Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 6x9 Riser Outlet Box (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 0.00 0.00 633.67 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.50 0.00 0.00 0.00 633.78 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.00 0.00 0.00 0.00 634.11 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.50 33.44 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H=.50; Htw=.00;
Qfree=33.44;
639.00 58.31 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H=1.00;Htw=.80;
Qfree=94.24;
639.50 64.09 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H=1.50;Htw=1.42;
Qfree=172.52;
639.83 67.08 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H=1.83;Htw=1.78;
Qfree=231.93;
640.00 67.78 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H=2.00;Htw=1.96;
Qfree=264.66;
640.50 72.52 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H=2.50;Htw=2.48;
Qfree=368.56;
641.00 75.04 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H=3.00;Htw=2.98;
Qfree=482.76;
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = Dual 24" Outlet Culverts (Culvert-Circular)
Mannings open channel maximum capacity: 18.80 ft3/s
Upstream ID = 4" Orifice, 18" Weir, 6x9 Riser Outlet Box
Downstream ID = Tailwater (Pond Outfall)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 Free Outfall 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.24 633.67 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .040ft Dcr= .117ft
H.JUMP IN PIPE
Hev= .00ft
637.37 0.40 0.00 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .050ft Dcr= .148ft
H.JUMP IN PIPE
Hev= .00ft
637.50 0.61 633.78 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .065ft Dcr= .191ft
CRIT.DEPTH Hev= .00ft
638.00 2.77 634.11 Free Outfall Free Outfall 0.00 0.01 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .142ft Dcr= .406ft
CRIT.DEPTH Hev= .00ft
638.50 39.01 636.36 Free Outfall Free Outfall 0.00 0.10 (N/A) 0.00 INLET CONTROL...
Submerged: HW =2.87
639.00 62.78 638.80 Free Outfall Free Outfall 0.00 0.08 (N/A) 0.00 INLET CONTROL...
Submerged: HW =5.31
639.50 67.53 639.42 Free Outfall Free Outfall 0.00 0.29 (N/A) 0.00 INLET CONTROL...
Submerged: HW =5.93
639.83 70.12 639.78 Free Outfall Free Outfall 0.00 0.40 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.29
640.00 71.38 639.96 Free Outfall Free Outfall 0.00 0.33 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.47
640.50 74.86 640.48 Free Outfall Free Outfall 0.00 0.63 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.99
641.00 78.17 640.98 Free Outfall Free Outfall 0.00 0.49 (N/A) 0.00 INLET CONTROL...
Submerged: HW =7.49
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 4" Orifice (Orifice-Circular)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.24 637.00 Free Outfall 633.67 0.00 0.00 (N/A) 0.00 H =.33
637.37 0.35 637.37 Free Outfall 0.00 0.00 0.00 (N/A) 0.00 H =.70
637.50 0.38 637.50 Free Outfall 633.78 0.00 0.00 (N/A) 0.00 H =.83
638.00 0.48 638.00 Free Outfall 634.11 0.00 0.00 (N/A) 0.00 H =1.33
638.50 0.57 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H =1.83
639.00 0.19 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H =.20
639.50 0.12 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H =.08
639.83 0.09 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H =.05
640.00 0.08 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H =.04
640.50 0.07 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H =.02
641.00 0.05 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H =.02
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 18" Weir (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 0.00 0.00 633.67 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.50 0.23 637.50 Free Outfall 633.78 0.00 0.00 (N/A) 0.00 H=.13; Htw=.00;
Qfree=.23;
638.00 2.29 638.00 Free Outfall 634.11 0.00 0.00 (N/A) 0.00 H=.63; Htw=.00;
Qfree=2.29;
638.50 5.10 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H=1.13;Htw=.00;
Qfree=5.10;
639.00 4.21 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H=1.63;Htw=1.43;
Qfree=8.14;
639.50 3.61 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H=2.13;Htw=2.05;
Qfree=11.12;
639.83 3.34 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H=2.46;Htw=2.41;
Qfree=12.95;
640.00 3.19 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H=2.63;Htw=2.59;
Qfree=13.83;
640.50 2.91 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H=3.13;Htw=3.11;
Qfree=16.12;
641.00 2.58 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H=3.63;Htw=3.61;
Qfree=17.83;
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Subsection: Composite Rating Curve Return Event: 1 years
Label: BMP 1 OS Storm Event: SCS Type II (2.92 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
636.50 0.00 (N/A) 0.00 (no Q: 4"Orifice,18"
Weir,6x9 Riser Outlet
Box,Dual 24"Outlet
Culverts,Emergency
Overflow)
637.00 0.24 (N/A) 0.00 4"Orifice,Dual 24"Outlet
Culverts (no Q: 18"
Weir,6x9 Riser Outlet
Box,Emergency Overflow)
637.37 0.35 (N/A) 0.00 4"Orifice,Dual 24"Outlet
Culverts (no Q: 18"
Weir,6x9 Riser Outlet
Box,Emergency Overflow)
637.50 0.61 (N/A) 0.00 4"Orifice,18"Weir,Dual
24"Outlet Culverts (no
Q: 6x9 Riser Outlet
Box,Emergency Overflow)
638.00 2.77 (N/A) 0.00 4"Orifice,18"Weir,Dual
24"Outlet Culverts (no
Q: 6x9 Riser Outlet
Box,Emergency Overflow)
638.50 39.01 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.00 62.78 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.50 67.53 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.83 70.12 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
640.00 77.90 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
640.50 125.87 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
641.00 195.86 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
Requested Pond Water Surface Elevations
Minimum (Headwater) 636.50 ft
Increment(Headwater) 0.50 ft
Maximum (Headwater) 641.00 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall El E2
(ft) (ft)
Orifice-Circular 4"Orifice Forward Dual 24" 636.50 641.00
Outlet
Culverts
Rectangular Weir 18"Weir Forward Dual 24" 637.37 641.00
Outlet
Culverts
Rectangular Weir 6x9 Riser Forward Dual 24" 638.00 641.00
Outlet Box Outlet
Culverts
Culvert-Circular Dual 24" Forward TW 633.49 641.00
Outlet
Culverts
Rectangular Weir Emergency Forward TW 639.83 641.00
Overflow
Tailwater Settings Tailwater (N/A) (N/A)
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
Structure ID: Emergency Overflow
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 639.83 ft
Weir Length 30.00 ft
Weir Coefficient 3.10(ft^0.5)/s
Structure ID: 6x9 Riser Outlet Box
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 638.00 ft
Weir Length 28.50 ft
Weir Coefficient 3.33 (ft^0.5)/s
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
Structure ID: Dual 24"Outlet Culverts
Structure Type: Culvert-Circular
Number of Barrels 2
Diameter 24.0 in
Length 57.00 ft
Length (Computed Barrel) 57.00 ft
Slope(Computed) 0.005 ft/ft
Outlet Control Data
Manning's n 0.012
Ke 0.500
Kb 0.011
Kr 0.500
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) 1.158
T2 ratio(HW/D) 1.304
Slope Correction Factor -0.500
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...
T1 Elevation 635.81 ft T1 Flow 15.55 ft3/s
T2 Elevation 636.10 ft T2 Flow 17.77 ft3/s
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
Structure ID: 4"Orifice
Structure Type: Orifice-Circular
Number of Openings 1
Elevation 636.50 ft
Orifice Diameter 4.0 in
Orifice Coefficient 0.600
Structure ID: 18"Weir
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 637.37 ft
Weir Length 1.50 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type Free Outfall
Convergence Tolerances
Maximum Iterations 50
Tailwater Tolerance 0.01 ft
(Minimum)
Tailwater Tolerance 0.50 ft
(Maximum)
Headwater Tolerance 0.01 ft
(Minimum)
Headwater Tolerance 0.50 ft
(Maximum)
Flow Tolerance(Minimum) 0.010 ft3/s
Flow Tolerance(Maximum) 10.000 ft3/s
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = Emergency Overflow (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Tailwater (Pond Outfall)
Water Surface Flow Tailwater Elevation Convergence Error Computation Messages
Elevation (ft3/s) (ft) (ft)
(ft)
636.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 (N/A) 0.00
637.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.50 0.00 (N/A) 0.00 WS below an invert; no
flow.
639.83 0.00 (N/A) 0.00 WS below an invert; no
flow.
640.00 6.52 (N/A) 0.00 H=.17; Htw=.00;
Qfree=6.52;
640.50 51.00 (N/A) 0.00 H=.67; Htw=.00;
Qfree=51.00;
641.00 117.70 (N/A) 0.00 H=1.17;Htw=.00;
Qfree=117.70;
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 6x9 Riser Outlet Box (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 0.00 0.00 633.67 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.50 0.00 0.00 0.00 633.78 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.00 0.00 0.00 0.00 634.11 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
638.50 33.44 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H=.50; Htw=.00;
Qfree=33.44;
639.00 58.31 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H=1.00;Htw=.80;
Qfree=94.24;
639.50 64.09 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H=1.50;Htw=1.42;
Qfree=172.52;
639.83 67.08 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H=1.83;Htw=1.78;
Qfree=231.93;
640.00 67.78 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H=2.00;Htw=1.96;
Qfree=264.66;
640.50 72.52 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H=2.50;Htw=2.48;
Qfree=368.56;
641.00 75.04 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H=3.00;Htw=2.98;
Qfree=482.76;
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = Dual 24" Outlet Culverts (Culvert-Circular)
Mannings open channel maximum capacity: 18.80 ft3/s
Upstream ID = 4" Orifice, 18" Weir, 6x9 Riser Outlet Box
Downstream ID = Tailwater (Pond Outfall)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 Free Outfall 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.24 633.67 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .040ft Dcr= .117ft
H.JUMP IN PIPE
Hev= .00ft
637.37 0.40 0.00 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .050ft Dcr= .148ft
H.JUMP IN PIPE
Hev= .00ft
637.50 0.61 633.78 Free Outfall Free Outfall 0.00 0.00 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .065ft Dcr= .191ft
CRIT.DEPTH Hev= .00ft
638.00 2.77 634.11 Free Outfall Free Outfall 0.00 0.01 (N/A) 0.00 CRIT.DEPTH CONTROL
Vh= .142ft Dcr= .406ft
CRIT.DEPTH Hev= .00ft
638.50 39.01 636.36 Free Outfall Free Outfall 0.00 0.10 (N/A) 0.00 INLET CONTROL...
Submerged: HW =2.87
639.00 62.78 638.80 Free Outfall Free Outfall 0.00 0.08 (N/A) 0.00 INLET CONTROL...
Submerged: HW =5.31
639.50 67.53 639.42 Free Outfall Free Outfall 0.00 0.29 (N/A) 0.00 INLET CONTROL...
Submerged: HW =5.93
639.83 70.12 639.78 Free Outfall Free Outfall 0.00 0.40 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.29
640.00 71.38 639.96 Free Outfall Free Outfall 0.00 0.33 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.47
640.50 74.86 640.48 Free Outfall Free Outfall 0.00 0.63 (N/A) 0.00 INLET CONTROL...
Submerged: HW =6.99
641.00 78.17 640.98 Free Outfall Free Outfall 0.00 0.49 (N/A) 0.00 INLET CONTROL...
Submerged: HW =7.49
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 4" Orifice (Orifice-Circular)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.24 637.00 Free Outfall 633.67 0.00 0.00 (N/A) 0.00 H =.33
637.37 0.35 637.37 Free Outfall 0.00 0.00 0.00 (N/A) 0.00 H =.70
637.50 0.38 637.50 Free Outfall 633.78 0.00 0.00 (N/A) 0.00 H =.83
638.00 0.48 638.00 Free Outfall 634.11 0.00 0.00 (N/A) 0.00 H =1.33
638.50 0.57 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H =1.83
639.00 0.19 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H =.20
639.50 0.12 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H =.08
639.83 0.09 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H =.05
640.00 0.08 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H =.04
640.50 0.07 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H =.02
641.00 0.05 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H =.02
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = 18" Weir (Rectangular Weir)
Upstream ID = (Pond Water Surface)
Downstream ID = Dual 24" Outlet Culverts (Culvert-Circular)
Water Device (into) Converge Next Downstream Convergence Downstream Tailwater Message
Surface Flow Headwater Downstream Downstream Hydraulic Error Channel Error
Elevation (ft3/s) Hydraulic Hydraulic Hydraulic Grade Line (ft3/s) Tailwater (ft)
(ft) Grade Line Grade Line Grade Line Error (ft)
(ft) (ft) (ft) (ft)
636.50 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.00 0.00 0.00 0.00 633.67 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.37 0.00 0.00 0.00 0.00 0.00 0.00 (N/A) 0.00 WS below an invert; no
flow.
637.50 0.23 637.50 Free Outfall 633.78 0.00 0.00 (N/A) 0.00 H=.13; Htw=.00;
Qfree=.23;
638.00 2.29 638.00 Free Outfall 634.11 0.00 0.00 (N/A) 0.00 H=.63; Htw=.00;
Qfree=2.29;
638.50 5.10 638.50 Free Outfall 636.36 0.00 0.00 (N/A) 0.00 H=1.13;Htw=.00;
Qfree=5.10;
639.00 4.21 639.00 638.80 638.80 0.00 0.00 (N/A) 0.00 H=1.63;Htw=1.43;
Qfree=8.14;
639.50 3.61 639.50 639.42 639.42 0.00 0.00 (N/A) 0.00 H=2.13;Htw=2.05;
Qfree=11.12;
639.83 3.34 639.83 639.78 639.78 0.00 0.00 (N/A) 0.00 H=2.46;Htw=2.41;
Qfree=12.95;
640.00 3.19 640.00 639.96 639.96 0.00 0.00 (N/A) 0.00 H=2.63;Htw=2.59;
Qfree=13.83;
640.50 2.91 640.50 640.48 640.48 0.00 0.00 (N/A) 0.00 H=3.13;Htw=3.11;
Qfree=16.12;
641.00 2.58 641.00 640.98 640.98 0.00 0.00 (N/A) 0.00 H=3.63;Htw=3.61;
Qfree=17.83;
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Subsection: Composite Rating Curve Return Event: 100 years
Label: BMP 1 OS Storm Event: SCS Type II (7.73 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
636.50 0.00 (N/A) 0.00 (no Q: 4"Orifice,18"
Weir,6x9 Riser Outlet
Box,Dual 24"Outlet
Culverts,Emergency
Overflow)
637.00 0.24 (N/A) 0.00 4"Orifice,Dual 24"Outlet
Culverts (no Q: 18"
Weir,6x9 Riser Outlet
Box,Emergency Overflow)
637.37 0.35 (N/A) 0.00 4"Orifice,Dual 24"Outlet
Culverts (no Q: 18"
Weir,6x9 Riser Outlet
Box,Emergency Overflow)
637.50 0.61 (N/A) 0.00 4"Orifice,18"Weir,Dual
24"Outlet Culverts (no
Q: 6x9 Riser Outlet
Box,Emergency Overflow)
638.00 2.77 (N/A) 0.00 4"Orifice,18"Weir,Dual
24"Outlet Culverts (no
Q: 6x9 Riser Outlet
Box,Emergency Overflow)
638.50 39.01 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.00 62.78 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.50 67.53 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
639.83 70.12 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts (no Q:
Emergency Overflow)
640.00 77.90 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
640.50 125.87 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
641.00 195.86 (N/A) 0.00 4"Orifice,18"Weir,6x9
Riser Outlet Box,Dual 24"
Outlet Culverts,Emergency
Overflow
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Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Requested Pond Water Surface Elevations
Minimum (Headwater) 636.00 ft
Increment(Headwater) 0.50 ft
Maximum (Headwater) 642.00 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall El E2
(ft) (ft)
User Defined Sand Media Forward 36"Outlet 0.00 642.00
Table Culvert
Rectangular Weir 12"Weir Forward 36"Outlet 637.50 642.00
Culvert
Rectangular Weir Riser Forward 36"Outlet 639.50 642.00
Outlet Box Culvert
Culvert-Circular 36"Outlet Forward TW 630.45 642.00
Culvert
Rectangular Weir Emergency Forward TW 640.50 642.00
Overflow
Tailwater Settings Tailwater (N/A) (N/A)
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Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Structure ID: Sand Media
Structure Type: User Defined Table
Elevation Flow
(ft) (ft3/s)
636.00 0.00
636.50 0.28
637.00 0.35
637.50 0.42
638.00 0.49
638.50 0.56
639.00 0.63
639.50 0.70
640.00 0.77
640.50 0.84
641.00 0.92
641.50 0.99
642.00 1.06
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Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Structure ID: 36"Outlet Culvert
Structure Type: Culvert-Circular
Number of Barrels 1
Diameter 36.0 in
Length 69.00 ft
Length (Computed Barrel) 69.00 ft
Slope(Computed) 0.005 ft/ft
Outlet Control Data
Manning's n 0.012
Ke 0.500
Kb 0.006
Kr 0.500
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) 1.158
T2 ratio(HW/D) 1.304
Slope Correction Factor -0.500
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...
T1 Elevation 633.92 ft T1 Flow 42.85 ft3/s
T2 Elevation 634.36 ft T2 Flow 48.97 ft3/s
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Subsection: Outlet Input Data Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Structure ID: Riser Outlet Box
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 639.50 ft
Weir Length 15.00 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: Emergency Overflow
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 640.50 ft
Weir Length 20.00 ft
Weir Coefficient 3.10(ft^0.5)/s
Structure ID: 12"Weir
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 637.50 ft
Weir Length 1.00 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type Free Outfall
Convergence Tolerances
Maximum Iterations 50
Tailwater Tolerance 0.01 ft
(Minimum)
Tailwater Tolerance 0.50 ft
(Maximum)
Headwater Tolerance 0.01 ft
(Minimum)
Headwater Tolerance 0.50 ft
(Maximum)
Flow Tolerance(Minimum) 0.010 ft3/s
Flow Tolerance(Maximum) 10.000 ft3/s
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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Subsection: Individual Outlet Curves Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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134

Subsection: Composite Rating Curve Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
636.00 0.00 (N/A) 0.00 (no Q: Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow)
636.50 0.29 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
637.00 0.34 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
637.50 0.42 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
638.00 1.56 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
638.50 3.22 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
639.00 4.91 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
639.50 6.36 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
640.00 24.89 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert (no Q:
Emergency Overflow)
640.50 57.05 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert (no Q:
Emergency Overflow)
641.00 117.18 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
641.50 164.88 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
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Subsection: Composite Rating Curve Return Event: 1 years
Label: BMP 2 OS Storm Event: SCS Type II (2.92 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
642.00 221.26 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Requested Pond Water Surface Elevations
Minimum (Headwater) 636.00 ft
Increment(Headwater) 0.50 ft
Maximum (Headwater) 642.00 ft
Outlet Connectivity
Structure Type Outlet ID Direction Outfall El E2
(ft) (ft)
User Defined Sand Media Forward 36"Outlet 0.00 642.00
Table Culvert
Rectangular Weir 12"Weir Forward 36"Outlet 637.50 642.00
Culvert
Rectangular Weir Riser Forward 36"Outlet 639.50 642.00
Outlet Box Culvert
Culvert-Circular 36"Outlet Forward TW 630.45 642.00
Culvert
Rectangular Weir Emergency Forward TW 640.50 642.00
Overflow
Tailwater Settings Tailwater (N/A) (N/A)
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Structure ID: Sand Media
Structure Type: User Defined Table
Elevation Flow
(ft) (ft3/s)
636.00 0.00
636.50 0.28
637.00 0.35
637.50 0.42
638.00 0.49
638.50 0.56
639.00 0.63
639.50 0.70
640.00 0.77
640.50 0.84
641.00 0.92
641.50 0.99
642.00 1.06
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Structure ID: 36"Outlet Culvert
Structure Type: Culvert-Circular
Number of Barrels 1
Diameter 36.0 in
Length 69.00 ft
Length (Computed Barrel) 69.00 ft
Slope(Computed) 0.005 ft/ft
Outlet Control Data
Manning's n 0.012
Ke 0.500
Kb 0.006
Kr 0.500
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) 1.158
T2 ratio(HW/D) 1.304
Slope Correction Factor -0.500
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...
T1 Elevation 633.92 ft T1 Flow 42.85 ft3/s
T2 Elevation 634.36 ft T2 Flow 48.97 ft3/s
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Subsection: Outlet Input Data Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Structure ID: Riser Outlet Box
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 639.50 ft
Weir Length 15.00 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: Emergency Overflow
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 640.50 ft
Weir Length 20.00 ft
Weir Coefficient 3.10(ft^0.5)/s
Structure ID: 12"Weir
Structure Type: Rectangular Weir
Number of Openings 1
Elevation 637.50 ft
Weir Length 1.00 ft
Weir Coefficient 3.33 (ft^0.5)/s
Structure ID: TW
Structure Type: TW Setup, DS Channel
Tailwater Type Free Outfall
Convergence Tolerances
Maximum Iterations 50
Tailwater Tolerance 0.01 ft
(Minimum)
Tailwater Tolerance 0.50 ft
(Maximum)
Headwater Tolerance 0.01 ft
(Minimum)
Headwater Tolerance 0.50 ft
(Maximum)
Flow Tolerance(Minimum) 0.010 ft3/s
Flow Tolerance(Maximum) 10.000 ft3/s
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Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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141

Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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142

Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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143

Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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144

Subsection: Individual Outlet Curves Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
RATING TABLE FOR ONE OUTLET TYPE
Structure ID = ()
Upstream ID =
Downstream ID =
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
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145

Subsection: Composite Rating Curve Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
636.00 0.00 (N/A) 0.00 (no Q: Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow)
636.50 0.29 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
637.00 0.34 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
637.50 0.42 (N/A) 0.00 Sand Media,36"Outlet
Culvert (no Q: 12"
Weir,Riser Outlet
Box,Emergency Overflow)
638.00 1.56 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
638.50 3.22 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
639.00 4.91 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
639.50 6.36 (N/A) 0.00 Sand Media,12"Weir,36"
Outlet Culvert (no Q:
Riser Outlet
Box,Emergency Overflow)
640.00 24.89 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert (no Q:
Emergency Overflow)
640.50 57.05 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert (no Q:
Emergency Overflow)
641.00 117.18 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
641.50 164.88 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
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146

Subsection: Composite Rating Curve Return Event: 100 years
Label: BMP 2 OS Storm Event: SCS Type II (7.73 in)
Composite Outflow Summary
Water Surface Flow Tailwater Elevation Convergence Error Contributing Structures
Elevation (ft3/s) (ft) (ft)
(ft)
642.00 221.26 (N/A) 0.00 Sand Media,12"
Weir,Riser Outlet Box,36"
Outlet Culvert,Emergency
Overflow
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147