SWA000215_Stormwater Report_20230706

ENGINEERINGOAK
STORMWATER MANAGEMENT
DESIGN REPORT
FOR
UNITED PLATE GLASS
EXPANSION
LINCOLN COUNTY, NORTH CAROLINA
A Rp .,,
re'rla`b
7 Ire
SEAL
5345
••%�N•n B... `,•
06/22/2023
BY
OAK ENGINEERING
4929 MONROE RD
CHARLOTTE, NC 28205
NC FIRM LICENSE: P-1742

ENGINEERINGOAK
TABLE OF CONTENTS
I. NARRATIVE
INTRODUCTION
STORMWATER MANAGEMENT REQUIREMENTS
EXISTING SITE CONDITIONS
PROPOSED SITE CONDITIONS
PROPOSED BMP DESIGN
CONCLUSIONS
II. MAPS AND FIGURES
HYDROCAD MODEL ROUTING DIAGRAM
USGS LOCATION MAP
DRAINAGE AREA MAPS
LINCOLN COUNTY RAINFALL DATA
SOILS MAP
FEMA FIRM MAP
III. HYDROCAD MODEL OUTPUT
HYDROCAD: 1-INCH STORM EVENT
HYDROCAD: 1 YR-24HR STORM EVENT
IV. HYDROFLOW STORM SEWERS MODEL OUTPUT
HYDRAFLOW STORM SEWERS: 10YR-24HR STORM EVENT
V. SEDIMENT & EROSION CONTROL DESIGN
SEDIMENT BASIN DESIGN
SKIMMER DESIGN
RIP RAP DESIGN

ENGINEERINGOAK
INTRODUCTION
United Plate Glass is proposing the construction of a 23,670-sf building expansion to their existing building in Lincoln County,
North Carolina. In addition to the proposed building expansion approximately 9,670-sf of impervious will be added for
vehicular parking spaces, and the existing gravel fire access will be re-aligned.
Lincoln County does not have any stormwater management requirements and the project is not in a designated Phase II area.
STORM WATER MANAGEMENT REQUIREMENTS
Lincoln County Storm water Management Requirements
1. None
NCDEQ State Storm water Management Requirements
1. Must provide 85% reduction (by weight) in the export of total suspended solids (TSS) on an average annual basis.
2. Must provide peak control for the 1 YR-24HR storm event.
The NCDEQ Stormwater Design Manua/was used as the basis for the water quality BMP design. One (1) sand filter was used
to provide the required treatment for the proposed improvements.
EXISTING SITE CONDITIONS
The 7.124 acre site has an existing 52,737-sf industrial building with associated vehicular parking, truck court, and fire
access. Existing drainage is collected in a storm drain system onsite which connects to the storm drain system on Lincoln
County Parkway.
Soils on the site are predominately Lloyd sandy clay loam, with HSG-B.
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See the Maps & Figures section of this report for Drainage Area and Soils Maps.

ENGINEERINGOAK
-
PROPOSED SITE CONDITIONS
As previously mentioned, the proposed improvements will include proposing the construction of a 23,670-sf building
expansion to their existing building in Lincoln County, North Carolina. In addition to the proposed building expansion
approximately 9,670-sf of impervious will be added for vehicular parking spaces, and the existing gravel fire access will be
re-aligned. The impervious parking and a portion of the existing building will be treated by the proposed sand filter. The
sand filter is sized to treat the equivalent of the building expansion and the impervious parking.
PRE/POST DEVELOPMENT SUMMARY TABLE
(flows in cfs)
z w
H
Z
w I> O L Q
E o N
Q > , Z U u_
a � � I" v
oC•1 ) o �1"WQ 0.00 0.73 0.08/865.10
lyr-24hr 0.89 4.78 0.15/866.97
1S
PRE (SOUTH
ZS OUTFALL)
POST TO SOUTH
FOREBAY SS
0
SOUTH SAND FILTER

ENGINEERINGOAK
MAPS & FIGURES
HYDROCAD MODEL ROUTING DIAGRAM
USGS LOCATION MAP
DRAINAGE AREA MAPS
CITY OF LUMBERTON RAINFALL DATA
SOILS MAP
FEMA FIRM MAP

1S
PRE (SOUTH
2S OUTFALL)
POST TO SOUTH SS
FOREBAY
SOUTH SAND FILTER
(Subca Reach and Link Routing Diagram for UPG SWM
Prepared by OAK Engineering, Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC

UPG SWM
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 2
Area Listing (all nodes)
Area CN Description
(acres) (subcatchment-numbers)
0.360 61 >75% Grass cover, Good, HSG B (2S)
1.110 98 Paved parking/Building, HSG B (2S)
16.370 55 Woods, Good, HSG B (1S)
17.840 58 TOTAL AREA

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NOAA Atlas 14,Volume 2,Version 3
":°` Location name: Lincolnton, North Carolina, USA* '"
V 1, Latitude: 35.5484°, Longitude: -81.2348° _ tl
• .acti
R. Elevation: 875 ft** �i
*source:ESRI Maps 'v ,f
°gyres°0 **source:USGS '""
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M.Bonnin,D.Martin,B.Lin,T.Parzybok,M.Yekta,and D.Riley
NOAA,National Weather Service,Silver Spring,Maryland
PF tabular I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Average recurrence interval (years)
Duration 1 2 5 10 25 50 100 200 500 _ 1000
5-min 0.383 0.453 0.533 0.593 0.665 0.718 0.769 0.817 0.877 0.923
(0.353-0.417) (0.418-0.495) (0.489-0.582) (0.542-0.646) (0.605-0.725) (0.648-0.782) (0.689-0.840), (0.726-0.896) (0.768-0.968) (0.799-1.02)
10-min 0.612 0.725 0.854 0.948 1.06 1.14 1.22 1.30 1.39 1.45
(0.563-0.666) (0.668-0.791) (0.784-0.931) (0.867-1.03) (0.964-1.16) (1.03-1.25) , (1.10-1.34) (1.15-1.42) (1.22-1.53) (1.26-1.61)
15-min 0.765 0.912 1.08 1.20 1.34 1.45 1.54 1.64 1.75 1.82
(0.704-0.832) (0.840-0.994) (0.991-1.18) (1.10-1.31) (1.22-1.46) (1.31-1.58) (1.38-1.69) (1.45-1.79) (1.53-1.93) (1.58-2.02)
30-min 1.05 1.26 1.54 1.74 1.99 2.18 2.36 2.54 2.78 2.95
(0.966-1.14) (1.16-1.37) (1.41-1.67) , (1.59-1.89) (1.81-2.17) (1.97-2.38) (2.12-2.58) (2.26-2.79) (2.44-3.07) (2.56-3.28)
1.31 1.58 1.97 2.26 2.65 2.95 3.26 3.57 3.99 4.31 I
60-min (1.20-1.42) (1.46-1.72) (1.81-2.15) (2.07-2.46) (2.41-2.89) (2.67-3.22) (2.92-3.56) (3.17-3.91) (3.49-4.40) (3.73-4.79)
2-hr 1.52 1.84 2.31 2.68 3.18 3.58 3.98 4.40 4.98 5.45
(1.39-1.66) (1.69-2.02) (2.12-2.53) (2.44-2.93) (2.88-3.47) (3.22-3.91) (3.56-4.37) I (3.89-4.85) (4.34-5.53) (4.68-6.08)
3-hr 1.63 1.96 2.48 2.88 3.44 3.90 4.38 4.89 5.61 6.19
(1.49-1.78) (1.80-2.16) (2.26-2.72) (2.62-3.16) (3.11-3.78) (3.50-4.29) (3.89-4.82) (4.30-5.40) (4.84-6.24) (5.28-6.93)I
6-hr 2.00 2.41 3.02 3.51 4.20 4.76 5.35 5.97 6.85 7.57
(1.84-2.18) (2.22-2.63) (2.77-3.30) (3.21-3.83) (3.81-4.58) (4.29-5.19) (4.78-5.85) (5.27-6.55) (5.95-7.56) (6.48-8.39)
12-hr 2.43 2.94 3.68 4.28 5.11 5.78 I 6.48 7.23 8.27 9.11
(2.25-2.65) (2.71-3.20) (3.39-4.01) (3.92-4.66) (4.65-5.56) (5.23-6.29) I (5.81-7.05) (6.40-7.86) (7.21-9.02) (7.84-9.97)
24-hr 2.94 3.56 4.50 I 5.23 6.23 7.04 7.86 8.72 9.89 10.8
(2.74-3.17) (3.31-3.84) (4.17-4.84) (4.84-5.63) (5.76-6.71) (6.48-7.57) (7.21-8.46) (7.96-9.39) (8.99-10.7) (9.79-11.7)
2-day 3.49 4.21 5.28 6.10 I 7.23 8.13 9.04 9.97 11.3 12.3
(3.24-3.77) (3.91-4.55) (4.90-5.70) i (5.65-6.58) j (6.68-7.79) (7.48-8.76) I (8.29-9.74) (9.12-10.8) (10.2-12.2) (11.1-13.3)
3-day 3.71 4.47 5.56 6.41 7.57 8.49 I 9.43 10.4 11.7 12.8
(3.45-3.99) (4.16-4.81) (5.16-5.98) (5.94-6.89) (7.00-8.14) (7.82-9.13) (8.66-10.1) (9.52-11.2) (10.7-12.6) (11.6-13.8)
4-day 3.93 4.72 5.84 6.72 7.91 8.86 9.82 10.8 12.2 13.2
(3.66-4.21) (4.40-5.07) (5.43-6.26) (6.23-7.21) (7.32-8.49) (8.17-9.50) (9.03-10.5) (9.91-11.6) (11.1-13.1) (12.0-14.3)
7-day 4.54 5.42 6.60 7.53 8.78 9.76 10.8 11.8 13.2 14.3
(4.25-4.84) (5.08-5.79) (6.18-7.04) (7.04-8.03) (8.18-9.37) (9.08-10.4) (9.98-11.5) (10.9-12.6) (12.1-14.1) (13.1-15.3)
10-day 5.19 6.18 7.42 8.38 9.66 10.7 11.7 12.7 14.0 15.1
(4.89-5.52) (5.82-6.57) (6.98-7.89) (7.88-8.91) (9.06-10.3) (9.96-11.3) (10.9-12.4) (11.8-13.5) (13.0-14.9) (13.9-16.1)
20-day 6.94 8.20 9.68 10.8 12.4 13.6 14.8 16.0 17.6 18.9
(6.57-7.32) (7.76-8.66) (9.16-10.2) (10.2-11.4) (11.7-13.1) (12.8-14.3) (13.9-15.6) (14.9-16.9) (16.4-18.7) (17.5-20.1)
30-day 8.53 10.0 11.6 12.8 14.4 15.5 16.7 17.8 19.3 20.4
(8.14-8.95) (9.58-10.5) (11.1-12.2) (12.2-13.4) (13.7-15.1) (14.7-16.3) i (15.8-17.5) I (16.9-18.7) (18.2-20.3) (19.2-21.6)
45-day 10.8 12.6 14.3 15.6 17.2 18.5 I 19.7 20.9 22.4 I 23.5
(10.3-11.2) (12.1-13.2) (13.7-14.9) (14.9-16.3) (16.5-18.0) (17.6-19.3) (18.8-20.6) (19.8-21.8) (21.2-23.5) (22.2-24.7)
60-day 12.8 14.9 16.8 18.2 20.1 21.4 22.7 24.0 25.6 26.8
(12.3-13.4) (14.3-15.6) (16.1-17.5) (17.5-19.0) (19.2-20.9) -(20.5-22.3) I (21.7-23.7) (22.9-25.0) (24.4-26.8) (25.5-28.1)
1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estimates
(for a given duration and average recurrence interval)will be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds
are not checked against probable maximum precipitation(PMP)estimates and may be higher than currently valid PMP values.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical

NOAA Atlas 14,Volume 2,Version 3
":°` Location name: Lincolnton, North Carolina, USA* +0
V 1, Latitude: 35.5484°, Longitude: -81.2348° _ Ma
• .acti
R. Elevation: 875 ft** i
*source:ESRI Maps 'v
°gyres°� **source:USGS ,"'""
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M.Bonnin,D.Martin,B.Lin,T.Parzybok,M.Yekta,and D.Riley
NOAA,National Weather Service,Silver Spring,Maryland
PF tabular I PF graphical I Maps & aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hour)1
Average recurrence interval (years)
Duration
1 2 5 10 25 50 100 200 500 1000
5-min 4.60 5.44 6.40 7.12 7.98 8.62 9.23 9.80 10.5 11.1
(4.24-5.00) (5.02-5.94) (5.87-6.98) (6.50-7.75) (7.26-8.70) (7.78-9.38) (8.27-10.1) (8.71-10.8) (9.22-11.6) (9.59-12.3)
10-min 3.67 4.35 5.12 5.69 6.36 6.86 7.33 7.78 8.32 8.72
(3.38-4.00) (4.01-4.75) (4.70-5.59) (5.20-6.19) (5.78-6.93) (6.20-7.48) (6.57-8.01) (6.91-8.52) (7.30-9.19) (7.55-9.68)
15-min 3.06 3.65 4.32 4.80 5.38 5.79 6.18 6.54 6.98 7.30
(2.82-3.33) (3.36-3.98) (3.96-4.71) (4.39-5.22) (4.89-5.86) (5.23-6.31) (5.54-6.75) (5.81-7.17) (6.12-7.71) (6.32-8.10)
30-min 2.10 2.52 3.07 3.48 3.98 4.36 4.73 5.09 5.56 5.91
(1.93-2.28) (2.32-2.75) (2.82-3.35) (3.18-3.78) (3.62-4.34) (3.94-4.75) (4.24-5.17) (4.52-5.58) (4.87-6.13) (5.11-6.56)
60-min 1.31 1.58 1.97 2.26 2.65 2.95 3.26 3.57 3.99 4.31
(1.20-1.42) (1.46-1.72) (1.81-2.15) (2.07-2.46) (2.41-2.89) (2.67-3.22) (2.92-3.56) (3.17-3.91) (3.49-4.40) (3.73-4.79)
2-hr 0.759 0.921 1.16 1.34 1.59 1.79 1.99 2.20 2.49 2.72
(0.697-0.829) (0.845-1.01) (1.06-1.26) (1.22-1.46) (1.44-1.74) (1.61-1.96) (1.78-2.18) (1.95-2.42) (2.17-2.76) (2.34-3.04)_
3-hr 0.541 0.654 I 0.824 0.958 1.15 1.30 1.46 1.63 1.87 2.06
(0.496-0.594) (0.600-0.719)1(0.753-0.905) (0.872-1.05) (1.04-1.26) (1.17-1.43) (1.30-1.61) (1.43-1.80) (1.61-2.08) (1.76-2.31)
6-hr 0.333 0.401 I 0.504 0.586 0.700 0.794 0.892 0.996 1.14 1.26
(0.307-0.364) (0.370-0.439) (0.463-0.551) (0.536-0.639) (0.636-0.764) (0.717-0.867) (0.797-0.976) (0.880-1.09) (0.993-1.26) (1.08-1.40)
12-hr 0.201 0.243 0.305 0.355 0.424 0.480 0.538 0.599 1 0.686 I 0.756
(0.186-0.219) (0.224-0.266)1(0.281-0.333) (0.325-0.386) (0.386-0.461) (0.433-0.521) (0.482-0.585) (0.530-0.652) (0.598-0.748) (0.650-0.827)
0
24-hr 0.122 0.148 0.187 0.217 0.259 I 0.293 0.327 0.363 0.412 0.451
(0.113-0.132) (0.137-0.160) (0.173-0.201) (0.201-0.234) (0.239-0.279) ( .270-0.315) (0.300-0.352) (0.331-0.391) (0.374-0.444) (0.408-0.487)
2-day 0.072 0.087 0.109 0.127 0.150 0.169 0.188 0.207 0.234 0.255
(0.067-0.078) (0.081-0.094)1 (0.102-0.118) (0.117-0.137) (0.139-0.162)1,(0.155-0.182) (0.172-0.202) (0.190-0.224) (0.213-0.253) (0.231-0.276)
3-day 0.051 0.062 0.077 I 0.089 0.105 0.117 0.130 0.144 0.162 0.177
(0.047-0.055) (0.057-0.066) (0.071-0.083) (0.082-0.095) (0.097-0.113) (0.108-0.126) (0.120-0.140) (0.132-0.155) (0.148-0.175) (0.160-0.191)
4-day 0.040 0.049 0.060 0.069 0.082 0.092 0.102 0.112 0.126 0.137
(0.038-0.043) (0.045-0.052)1(0.056-0.065),(0.064-0.075) (0.076-0.088) (0.085-0.099) (0.094-0.109) (0.103-0.121)1 (0.115-0.136) (0.125-0.148)
7-day 0.026 0.032 I 0.039 0.044 0.052 0.058 0.064 0.070 0.078 0.084
(0.025-0.028) (0.030-0.034) (0.036-0.041) (0.041-0.047) (0.048-0.055) (0.054-0.062) (0.059-0.068) (0.064-0.075) (0.072-0.083) (0.077-0.091)
10-day 0.021 0.025 0.030 0.034 0.040 0.044 0.048 0.052 0.058 0.062
(0.020-0.022) (0.024-0.027)1(0.029-0.032) (0.032-0.037) (0.037-0.042) (0.041-0.047) (0.045-0.051) (0.049-0.056) (0.054-0.062) (0.058-0.067)
20-day 0.014 0.017 0.020 0.022 0.025 0.028 0.030 0.033 0.036 0.039
(0.013-0.015) (0.016-0.018) (0.019-0.021) (0.021-0.023) (0.024-0.027) (0.026-0.029) (0.028-0.032) (0.031-0.035) (0.034-0.038) (0.036-0.041)
30-day 0.011 0.013 0.016 0.017 0.019 0.021 0.023 0.024 0.026 0.028
(0.011-0.012) (0.013-0.014) (0.015-0.016) (0.016-0.018) (0.018-0.020) (0.020-0.022) (0.021-0.024) (0.023-0.026) (0.025-0.028) (0.026-0.029)
45-day 0.009 0.011 0.013 0.014 0.015 0.017 0.018 0.019 0.020 0.021
(0.009-0.010) (0.011-0.012) (0.012-0.013) (0.013-0.015) (0.015-0.016) (0.016-0.017) (0.017-0.019) (0.018-0.020) (0.019-0.021) (0.020-0.022)1
60-day 0.008 0.010 0.011 I 0.012 0.013 0.014 0.015 0.016 0.017 0.018
(0.008-0.009) (0.009-0.01011 (0.011-0.012),(0.012-0.013) (0.013-0.014) (0.014-0.015) (0.015-0.016) (0.015-0.017) (0.016-0.018) (0.017-0.019)
1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estimates(for
a given duration and average recurrence interval)will be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds are not
checked against probable maximum precipitation(PMP)estimates and may be higher than currently valid PMP values.
Please refer to NOAAAtlas 14 document for more information.
Back to Top
PF graphical

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Hydrologic Soil Group—Lincoln County, North Carolina
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
LcD Lloyd loam, 15 to 25 B 1.6 20.8%
percent slopes
LdB2 Lloyd sandy clay loam,2 B 2.6 34.7%
to 8 percent slopes,
moderately eroded
LdC2 Lloyd sandy clay loam,8 B 3.3 44.4%
to 15 percent slopes,
moderately eroded
Totals for Area of Interest 7.5 100.0%
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive
precipitation from long-duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D)and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential)when
thoroughly wet. These consist mainly of deep, well drained to excessively
drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well
drained soils that have moderately fine texture to moderately coarse texture.
These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of
water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential)when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay
layer at or near the surface, and soils that are shallow over nearly impervious
material. These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in
their natural condition are in group D are assigned to dual classes.
USDA Natural Resources Web Soil Survey 5/31/2023
Conservation Service National Cooperative Soil Survey Page 3 of 4

Hydrologic Soil Group—Lincoln County, North Carolina
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff:None Specified
Tie-break Rule: Higher
USDA Natural Resources Web Soil Survey 5/31/2023
Conservation Service National Cooperative Soil Survey Page 4 of 4

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ENGINEERINGOAK
SAND FILTER DESIGN

OAK
ENGINEERING
SOUTH SAND FILTER
COMPUTE WATER QUALITY VOLUME
Drainage Area= 1.47 ac
%Impervious= 75.50 %
Curve Number= 89.00
USE SIMPLE METHOD Rv=0.05+0.009(I)
0.7295 IN/IN
P= 1.0 IN
S= .236a
PModified = 1.63
WQV=Ili 3,893 ft3
WQV Ad'= 2,920 ft'
DETERMINE FILTER BED & SEDIMENTATION BASIN SURFACE AREA
h MaxFilter= WQV Adi (ft3)
A,(ft2)+Af(ft2)
Assume h MaxFilter
h MaxFilter 3.00 ft vlin. (A,+AF)= 2,7,11 ft`
Min.Area for Sedimentation Chamber Min.Area for Sand Filter
As=0.66(WQVadi) Af= WQVx 1.5 ft
3.5 ft/day x 1.66 days x/Avg Head+ 1.5 ft)
As= 1,927 ft` Af= ft` Elev
Bottom Area Used= 1,181 ft2 (865) Bottom Area Used = 466 ft2 864.75
To. Area Used = 4,013 ft2 (868) Top Area Used =®ft2 867
6,239 ft3 1,641 ft3
VERIFY VOLUMES
Voltatai= (A,+Af)X hMaxFilter
Voltatai=■ 7,880 fe COMPARE TO WQVad1 OK
SIZE UNDERDRAIN SYSTEM
Determine capacity o Under Drain System
Af=WQvxdf/[ (kxHf+Df)xTf]
Where:
Af= 293 ft2 surface area of filter bed
df= 1.5 ft filter bed depth
k= 4 ft/day coefficient of permeability media
hf= 1.50 ft average height of water above filter bed, (Hmax/2)
Tf= 1.66 Days (40 Hours, 1.66 Days))
3.3 Ft Max. Depth of Storage Volume
Af Provided= 364 ft` surface area provided
Q at Full Depth= 0.053 cfs
Q at Avg Depth= 0.035 cfs
Time to Drain= 30.90 hrs
Safety Factor of 10 0.350 cfs

OAK
ENGINEER ING
Compute Perforation Capacity
Pipes Length 4 Holes/Row
#of Perforations= 1 45 4 = 360 3/8" Dia. Holes spaced 6"O.C.
50%of Perforations=_ J Holes
:opacity of One Hole= CA(2gh)^0.5
cfs/Hole
Total Capacity= cfs
Capacity of Filter Media= cfs
Media
Perforation Capacity= > Capacity
BOUYANCY CALCULATIONS
OS-1
Top of Structure= 745.00
Bottom of Structure= 740.18
Width of Box= 5.00 ft(O.D.)
Length of Box= 5.00 ft(O.D.)
BF= VOLstruct x densityH2O (62.4 lb/cf)
7,519,lbs
Weight of Structure(see calcs, next page)
6,989 lbs
Weight of Concrete= 145-62.4(Ib/cf) = 87.6 lb/cf
SF= 1.25
Weight of anchor
lbs
required:
Volume of anchor
cf
required:
Anchor Dimensions: L= 5 ft Thickness Reqd= ft
W= 5 ft in
Page 2 of 2

ENGINEERINGOAK
HYDROCAD OUTPUT
1-INCH STORM EVENT

UPG SWM Type II 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: PRE (SOUTH OUTFALL)
[45] Hint: Runoff=Zero
Runoff = 0.00 cfs @ 5.00 hrs, Volume= 0.000 af, Depth= 0.00"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1" Water Quality Rainfall=1.00"
Area (ac) CN Description
16.370 55 Woods, Good, HSG B
16.370 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
7.1 49 0.0700 0.11 Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.39"
10.9 952 0.0850 1.46 Shallow Concentrated Flow,
Woodland Kv= 5.0 fps
18.0 1,001 Total
Subcatchment 1S: PRE (SOUTH OUTFALL)
Hydrograph
1y
0 Runoff
Type II 24-hr
1"Wate Quality Rainfall=1.00"
unoff Area=16.370 ac
R noff Volume=0.000 af
Runoff Depth=0.00"
Flow Length=1,001'
Tc=18.0 min
CN=55
°JP)/�������llll�llll�llll�llll�llll�ll��������������������������///////////%
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

UPG SWM Type ll 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: PRE (SOUTH OUTFALL)
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.06 0.00 0.00 19.25 0.94 0.00 0.00
5.25 0.07 0.00 0.00 19.50 0.95 0.00 0.00
5.50 0.07 0.00 0.00 19.75 0.95 0.00 0.00
5.75 0.08 0.00 0.00 20.00 0.95 0.00 0.00
6.00 0.08 0.00 0.00
6.25 0.08 0.00 0.00
6.50 0.09 0.00 0.00
6.75 0.09 0.00 0.00
7.00 0.10 0.00 0.00
7.25 0.10 0.00 0.00
7.50 0.11 0.00 0.00
7.75 0.11 0.00 0.00
8.00 0.12 0.00 0.00
8.25 0.13 0.00 0.00
8.50 0.13 0.00 0.00
8.75 0.14 0.00 0.00
9.00 0.15 0.00 0.00
9.25 0.16 0.00 0.00
9.50 0.16 0.00 0.00
9.75 0.17 0.00 0.00
10.00 0.18 0.00 0.00
10.25 0.19 0.00 0.00
10.50 0.20 0.00 0.00
10.75 0.22 0.00 0.00
11.00 0.24 0.00 0.00
11.25 0.26 0.00 0.00
11.50 0.28 0.00 0.00
11.75 0.39 0.00 0.00
12.00 0.66 0.00 0.00
12.25 0.71 0.00 0.00
12.50 0.73 0.00 0.00
12.75 0.76 0.00 0.00
13.00 0.77 0.00 0.00
13.25 0.79 0.00 0.00
13.50 0.80 0.00 0.00
13.75 0.81 0.00 0.00
14.00 0.82 0.00 0.00
14.25 0.83 0.00 0.00
14.50 0.84 0.00 0.00
14.75 0.85 0.00 0.00
15.00 0.85 0.00 0.00
15.25 0.86 0.00 0.00
15.50 0.87 0.00 0.00
15.75 0.87 0.00 0.00
16.00 0.88 0.00 0.00
16.25 0.89 0.00 0.00
16.50 0.89 0.00 0.00
16.75 0.90 0.00 0.00
17.00 0.90 0.00 0.00
17.25 0.91 0.00 0.00
17.50 0.91 0.00 0.00
17.75 0.92 0.00 0.00
18.00 0.92 0.00 0.00
18.25 0.93 0.00 0.00
18.50 0.93 0.00 0.00
18.75 0.93 0.00 0.00
19.00 0.94 0.00 0.00

UPG SWM Type II 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 2S: POST TO SOUTH FOREBAY
[49] Hint: Tc<2dt may require smaller dt
Runoff = 0.73 cfs @ 11.97 hrs, Volume= 0.031 af, Depth> 0.26"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1" Water Quality Rainfall=1.00"
Area (ac) CN Description
* 1.110 98 Paved parking / Building, HSG B
0.360 61 >75% Grass cover, Good, HSG B
1.470 89 Weighted Average
0.360 24.49% Pervious Area
1.110 75.51% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 2S: POST TO SOUTH FOREBAY
Hydrograph
os: 0 Runoff
o.75J 10.73 cfs
Type II 24-hr
0.650.5Y 1''Water Quality Rainfall=1.00"
o.6J Runoff Area=1.470 ac
0.55/ Runoff Volume=0.031 of
Runoff Depth>0.26"
0.45/' Tc=5.0 rin
3 0.4: / ►-R9
u. 0.35J
0.3/.
0.25V
0.2V
0.15V/
0.1J
0.05J ��Z
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

UPG SWM Type ll 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 4
Hydrograph for Subcatchment 2S: POST TO SOUTH FOREBAY
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.06 0.00 0.00 19.25 0.94 0.25 0.01
5.25 0.07 0.00 0.00 19.50 0.95 0.25 0.01
5.50 0.07 0.00 0.00 19.75 0.95 0.25 0.01
5.75 0.08 0.00 0.00 20.00 0.95 0.26 0.01
6.00 0.08 0.00 0.00
6.25 0.08 0.00 0.00
6.50 0.09 0.00 0.00
6.75 0.09 0.00 0.00
7.00 0.10 0.00 0.00
7.25 0.10 0.00 0.00
7.50 0.11 0.00 0.00
7.75 0.11 0.00 0.00
8.00 0.12 0.00 0.00
8.25 0.13 0.00 0.00
8.50 0.13 0.00 0.00
8.75 0.14 0.00 0.00
9.00 0.15 0.00 0.00
9.25 0.16 0.00 0.00
9.50 0.16 0.00 0.00
9.75 0.17 0.00 0.00
10.00 0.18 0.00 0.00
10.25 0.19 0.00 0.00
10.50 0.20 0.00 0.00
10.75 0.22 0.00 0.00
11.00 0.24 0.00 0.00
11.25 0.26 0.00 0.00
11.50 0.28 0.00 0.01
11.75 0.39 0.01 0.11
12.00 0.66 0.10 0.68
12.25 0.71 0.12 0.11
12.50 0.73 0.14 0.07
12.75 0.76 0.15 0.06
13.00 0.77 0.16 0.05
13.25 0.79 0.16 0.04
13.50 0.80 0.17 0.04
13.75 0.81 0.18 0.03
14.00 0.82 0.18 0.03
14.25 0.83 0.19 0.03
14.50 0.84 0.19 0.03
14.75 0.85 0.20 0.03
15.00 0.85 0.20 0.02
15.25 0.86 0.20 0.02
15.50 0.87 0.21 0.02
15.75 0.87 0.21 0.02
16.00 0.88 0.21 0.02
16.25 0.89 0.22 0.02
16.50 0.89 0.22 0.02
16.75 0.90 0.22 0.02
17.00 0.90 0.23 0.02
17.25 0.91 0.23 0.02
17.50 0.91 0.23 0.02
17.75 0.92 0.24 0.02
18.00 0.92 0.24 0.02
18.25 0.93 0.24 0.02
18.50 0.93 0.24 0.01
18.75 0.93 0.25 0.01
19.00 0.94 0.25 0.01

UPG SWM Type ll 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond SSF: SOUTH SAND FILTER
Inflow Area = 1.470 ac, 75.51% Impervious, Inflow Depth > 0.26" for 1"Water Quality event
Inflow = 0.73 cfs @ 11.97 hrs, Volume= 0.031 af
Outflow = 0.08 cfs @ 12.44 hrs, Volume= 0.031 af, Atten= 89%, Lag= 28.3 min
Primary = 0.08 cfs @ 12.44 hrs, Volume= 0.031 af
Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 865.10' @ 12.44 hrs Surf.Area= 2,145 sf Storage= 518 cf
Plug-Flow detention time= 64.3 min calculated for 0.031 af(98% of inflow)
Center-of-Mass det. time= 58.6 min ( 872.0-813.4 )
Volume Invert Avail.Storage Storage Description
#1 864.75' 9,336 cf Custom Stage Data (Prismatic) Listed below(Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
864.75 364 0 0
865.00 2,087 306 306
866.00 2,669 2,378 2,684
867.00 3,311 2,990 5,674
868.00 4,013 3,662 9,336
Device Routing Invert Outlet Devices
#1 Device 2 864.75' 2.000 in/hr Sand Filter over Surface area above 864.75'
Conductivity to Groundwater Elevation = 851.00'
Excluded Surface area = 364 sf
#2 Primary 862.15' 15.0" Round Culvert
L= 78.8' RCP, square edge headwall, Ke=0.500
Inlet/Outlet Invert= 862.15'/861.76' S= 0.0049 '/' Cc= 0.900
n= 0.012, Flow Area= 1.23 sf
#3 Device 2 867.75' 36.0"Vert. Top of OS C= 0.600
Primary OutFlow Max=0.08 cfs @ 12.44 hrs HW=865.10' (Free Discharge)
4r-2=Culvert (Passes 0.08 cfs of 8.13 cfs potential flow)
'L1=Sand Filter ( Controls 0.08 cfs)
3=Top of OS ( Controls 0.00 cfs)

UPG SWM Type II 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 6
Pond SSF: SOUTH SAND FILTER
Hydrograph
DInflow
0.8 10.73 cfs i ❑Primary
0.75y Inflow Area=1.470 ac
065 Peak lev=865.10'
0.6:/ Sto age=518 cf
0.55y
0.5-
0.45y
0 0.4V
a 0.35�
0.3y
0.25-
0.2�0.15=
0.08 cfs
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
Pond SSF: SOUTH SAND FILTER
Stage-Discharge
■Primary
870J
869J ''___
/'
w 867
866
865 /
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Discharge (cfs)

UPG SWM Type ll 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 7
Pond SSF: SOUTH SAND FILTER
Stage-Area-Storage
Surface/Horizontal/Wetted Area(sq-ft)
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 E Surface
I0 Storage
870
869i/
868
w 867
866—//
865 Custom Stage Data � / / / //
0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000
Storage(cubic-feet)

UPG SWM Type ll 24-hr 1" Water Quality Rainfall=1.00"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 8
Hydrograph for Pond SSF: SOUTH SAND FILTER
Time Inflow Storage Elevation Primary
(hours) (cfs) (cubic-feet) (feet) (cfs)
5.00 0.00 0 864.75 0.00
5.50 0.00 0 864.75 0.00
6.00 0.00 0 864.75 0.00
6.50 0.00 0 864.75 0.00
7.00 0.00 0 864.75 0.00
7.50 0.00 0 864.75 0.00
8.00 0.00 0 864.75 0.00
8.50 0.00 0 864.75 0.00
9.00 0.00 0 864.75 0.00
9.50 0.00 0 864.75 0.00
10.00 0.00 0 864.75 0.00
10.50 0.00 0 864.75 0.00
11.00 0.00 0 864.75 0.00
11.50 0.01 2 864.76 0.00
12.00 0.68 363 865.03 0.08
12.50 0.07 517 865.10 0.08
13.00 0.05 472 865.08 0.08
13.50 0.04 401 865.04 0.08
14.00 0.03 316 865.00 0.08
14.50 0.03 232 864.96 0.07
15.00 0.02 168 864.92 0.06
15.50 0.02 120 864.89 0.05
16.00 0.02 85 864.86 0.04
16.50 0.02 61 864.84 0.03
17.00 0.02 46 864.82 0.02
17.50 0.02 37 864.81 0.02
18.00 0.02 32 864.81 0.02
18.50 0.01 28 864.80 0.02
19.00 0.01 25 864.80 0.02
19.50 0.01 23 864.79 0.01
20.00 0.01 20 864.79 0.01

ENGINEERINGOAK
HYDROCAD OUTPUT
1-YEAR, 24-HOUR STORM EVENT

UPG SWM Type II 24-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 1
Summary for Subcatchment 1 S: PRE (SOUTH OUTFALL)
Runoff = 0.89 cfs @ 12.23 hrs, Volume= 0.194 af, Depth> 0.14"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1yr-24hr Rainfall=2.94"
Area (ac) CN Description
16.370 55 Woods, Good, HSG B
16.370 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
7.1 49 0.0700 0.11 Sheet Flow,
Woods: Light underbrush n= 0.400 P2= 3.39"
10.9 952 0.0850 1.46 Shallow Concentrated Flow,
Woodland Kv= 5.0 fps
18.0 1,001 Total
Subcatchment 1S: PRE (SOUTH OUTFALL)
Hydrograph
0.95�
■Runoff
0.9� I o.8s cfs
0.85J Type 1124-h r
08 II 1yr-24hr Rainfall=2.94"
0.7 Runoff Area=16.370 ac
0.65�
0.6� Runoff Volume=0.194 af
°
3 051/ Runoff Depth>0.14"
LL 004 4 Flow Length=1,001'
0.35 , �i/ Tc=18,0 min
0.3/ pIY_�
0.25� '������ C JJ
0.15 We
0.1
0.05 / /
0E4(7Y ffffl�A%(S�A%f �fS�S�� r, r , , , ,,
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

UPG SWM Type 1124-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 2
Hydrograph for Subcatchment 1S: PRE (SOUTH OUTFALL)
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.19 0.00 0.00 19.25 2.77 0.14 0.17
5.25 0.20 0.00 0.00 19.50 2.78 0.14 0.17
5.50 0.21 0.00 0.00 19.75 2.79 0.14 0.16
5.75 0.22 0.00 0.00 20.00 2.80 0.14 0.15
6.00 0.24 0.00 0.00
6.25 0.25 0.00 0.00
6.50 0.26 0.00 0.00
6.75 0.28 0.00 0.00
7.00 0.29 0.00 0.00
7.25 0.31 0.00 0.00
7.50 0.32 0.00 0.00
7.75 0.34 0.00 0.00
8.00 0.35 0.00 0.00
8.25 0.37 0.00 0.00
8.50 0.39 0.00 0.00
8.75 0.41 0.00 0.00
9.00 0.43 0.00 0.00
9.25 0.46 0.00 0.00
9.50 0.48 0.00 0.00
9.75 0.50 0.00 0.00
10.00 0.53 0.00 0.00
10.25 0.56 0.00 0.00
10.50 0.60 0.00 0.00
10.75 0.64 0.00 0.00
11.00 0.69 0.00 0.00
11.25 0.75 0.00 0.00
11.50 0.83 0.00 0.00
11.75 1.14 0.00 0.00
12.00 1.95 0.01 0.08
12.25 2.08 0.02 0.88
12.50 2.16 0.03 0.71
12.75 2.22 0.04 0.55
13.00 2.27 0.05 0.47
13.25 2.31 0.05 0.42
13.50 2.35 0.06 0.39
13.75 2.38 0.06 0.36
14.00 2.41 0.07 0.33
14.25 2.44 0.07 0.30
14.50 2.46 0.08 0.29
14.75 2.49 0.08 0.29
15.00 2.51 0.08 0.28
15.25 2.53 0.09 0.27
15.50 2.55 0.09 0.26
15.75 2.57 0.10 0.25
16.00 2.59 0.10 0.23
16.25 2.60 0.10 0.22
16.50 2.62 0.11 0.22
16.75 2.64 0.11 0.21
17.00 2.65 0.11 0.21
17.25 2.67 0.12 0.21
17.50 2.68 0.12 0.20
17.75 2.69 0.12 0.20
18.00 2.71 0.12 0.20
18.25 2.72 0.13 0.19
18.50 2.73 0.13 0.19
18.75 2.75 0.13 0.18
19.00 2.76 0.13 0.18

UPG SWM Type II 24-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 2S: POST TO SOUTH FOREBAY
[49] Hint: Tc<2dt may require smaller dt
Runoff = 4.78 cfs @ 11.95 hrs, Volume= 0.210 af, Depth> 1.72"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Type II 24-hr 1yr-24hr Rainfall=2.94"
Area (ac) CN Description
* 1.110 98 Paved parking / Building, HSG B
0.360 61 >75% Grass cover, Good, HSG B
1.470 89 Weighted Average
0.360 24.49% Pervious Area
1.110 75.51% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 2S: POST TO SOUTH FOREBAY
Hydrograph
/ 0 Runoff
5— 14.78 cfs I
Type II 24-h r
4- 1yr-24hr Rainfall=2.94"
Runoff Area=1.470 ac
Runoff Volume=0.210 af
3 Runoff Depth>1.72"
LL Tc=5.0 min
2 / CN=89
/
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)

UPG SWM Type 1124-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 4
Hydrograph for Subcatchment 2S: POST TO SOUTH FOREBAY
Time Precip. Excess Runoff Time Precip. Excess Runoff
(hours) (inches) (inches) (cfs) (hours) (inches) (inches) (cfs)
5.00 0.19 0.00 0.00 19.25 2.77 1.69 0.06
5.25 0.20 0.00 0.00 19.50 2.78 1.70 0.06
5.50 0.21 0.00 0.00 19.75 2.79 1.71 0.05
5.75 0.22 0.00 0.00 20.00 2.80 1.72 0.05
6.00 0.24 0.00 0.00
6.25 0.25 0.00 0.00
6.50 0.26 0.00 0.00
6.75 0.28 0.00 0.00
7.00 0.29 0.00 0.01
7.25 0.31 0.00 0.01
7.50 0.32 0.00 0.01
7.75 0.34 0.01 0.01
8.00 0.35 0.01 0.01
8.25 0.37 0.01 0.02
8.50 0.39 0.01 0.02
8.75 0.41 0.02 0.03
9.00 0.43 0.02 0.03
9.25 0.46 0.03 0.04
9.50 0.48 0.04 0.04
9.75 0.50 0.04 0.05
10.00 0.53 0.05 0.06
10.25 0.56 0.06 0.07
10.50 0.60 0.08 0.08
10.75 0.64 0.10 0.11
11.00 0.69 0.12 0.13
11.25 0.75 0.15 0.19
11.50 0.83 0.19 0.26
11.75 1.14 0.37 1.42
12.00 1.95 0.99 4.11
12.25 2.08 1.09 0.59
12.50 2.16 1.16 0.38
12.75 2.22 1.21 0.29
13.00 2.27 1.26 0.24
13.25 2.31 1.29 0.21
13.50 2.35 1.32 0.18
13.75 2.38 1.35 0.16
14.00 2.41 1.38 0.15
14.25 2.44 1.40 0.14
14.50 2.46 1.42 0.13
14.75 2.49 1.44 0.12
15.00 2.51 1.46 0.12
15.25 2.53 1.48 0.11
15.50 2.55 1.50 0.10
15.75 2.57 1.52 0.10
16.00 2.59 1.53 0.09
16.25 2.60 1.55 0.09
16.50 2.62 1.56 0.08
16.75 2.64 1.57 0.08
17.00 2.65 1.59 0.08
17.25 2.67 1.60 0.08
17.50 2.68 1.61 0.08
17.75 2.69 1.63 0.07
18.00 2.71 1.64 0.07
18.25 2.72 1.65 0.07
18.50 2.73 1.66 0.07
18.75 2.75 1.67 0.06
19.00 2.76 1.68 0.06

UPG SWM Type 1124-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 5
Summary for Pond SSF: SOUTH SAND FILTER
Inflow Area = 1.470 ac, 75.51% Impervious, Inflow Depth > 1.72" for 1yr-24hr event
Inflow = 4.78 cfs @ 11.95 hrs, Volume= 0.210 of
Outflow = 0.15 cfs @ 13.93 hrs, Volume= 0.112 af, Atten= 97%, Lag= 118.3 min
Primary = 0.15 cfs @ 13.93 hrs, Volume= 0.112 of
Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs
Peak Elev= 866.97' @ 13.93 hrs Surf.Area= 3,291 sf Storage= 5,573 cf
Plug-Flow detention time=216.8 min calculated for 0.112 of(53% of inflow)
Center-of-Mass det. time= 140.6 min ( 913.0 - 772.4 )
Volume Invert Avail.Storage Storage Description
#1 864.75' 9,336 cf Custom Stage Data (Prismatic) Listed below(Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (sq-ft) (cubic-feet) (cubic-feet)
864.75 364 0 0
865.00 2,087 306 306
866.00 2,669 2,378 2,684
867.00 3,311 2,990 5,674
868.00 4,013 3,662 9,336
Device Routing Invert Outlet Devices
#1 Device 2 864.75' 2.000 in/hr Sand Filter over Surface area above 864.75'
Conductivity to Groundwater Elevation = 851.00'
Excluded Surface area = 364 sf
#2 Primary 862.15' 15.0" Round Culvert
L= 78.8' RCP, square edge headwall, Ke=0.500
Inlet/Outlet Invert= 862.15'/861.76' S= 0.0049 '/' Cc= 0.900
n= 0.012, Flow Area= 1.23 sf
#3 Device 2 867.75' 36.0"Vert.Top of OS C= 0.600
Primary OutFlow Max=0.15 cfs @ 13.93 hrs HW=866.97' (Free Discharge)
4r-2=Culvert (Passes 0.15 cfs of 11.19 cfs potential flow)
'L1=Sand Filter ( Controls 0.15 cfs)
3=Top of OS ( Controls 0.00 cfs)

UPG SWM Type II 24-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 6
Pond SSF: SOUTH SAND FILTER
Hydrograph
I ■Inflow
14.7 cfs Jy ■Primary
5 Inflow Area=1.470 ac
Peak EIev=866.97'
4
Storage=5,573 cf
3_
o
LL 2J
•
0 15 cfs
1J
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Time (hours)
Pond SSF: SOUTH SAND FILTER
Stage-Discharge
// ■Primary
870J
869J ''___
868 ���o����
c /'
•=
w 867
866 %
865 / SadFiltery " „ „
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Discharge (cfs)

UPG SWM Type II 24-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 7
Pond SSF: SOUTH SAND FILTER
Stage-Area-Storage
Surface/Horizontal/Wetted Area(sq-ft)
0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 Surface
01 I I •••I I I 0 Storage
870 0
�1111111 I
�
869
-,-„,
868 �I i 1111 MYWd I
w II
867 III p��������� -O I
866
IP.mil.
. iim..mi - I I I
/ii1MommumW��I�■ ■ MI
865 Custom a Data M���
0 1,000 2,000 3,000 4,000 5,000 6,000 7,000 8,000 9,000
Storage(cubic-feet)

UPG SWM Type 1124-hr lyr-24hr Rainfall=2.94"
Prepared by OAK Engineering Printed 6/16/2023
HydroCAD®10.00-20 s/n 10066 ©2017 HydroCAD Software Solutions LLC Page 8
Hydrograph for Pond SSF: SOUTH SAND FILTER
Time Inflow Storage Elevation Primary
(hours) (cfs) (cubic-feet) (feet) (cfs)
5.00 0.00 0 864.75 0.00
5.50 0.00 0 864.75 0.00
6.00 0.00 0 864.75 0.00
6.50 0.00 0 864.75 0.00
7.00 0.01 4 864.76 0.00
7.50 0.01 9 864.77 0.01
8.00 0.01 15 864.78 0.01
8.50 0.02 24 864.80 0.01
9.00 0.03 40 864.82 0.02
9.50 0.04 60 864.84 0.03
10.00 0.06 86 864.86 0.04
10.50 0.08 135 864.90 0.05
11.00 0.13 226 864.96 0.07
11.50 0.26 428 865.06 0.08
12.00 4.11 3,725 866.37 0.13
12.50 0.38 5,177 866.85 0.15
13.00 0.24 5,440 866.93 0.15
13.50 0.18 5,549 866.96 0.15
14.00 0.15 5,573 866.97 0.15
14.50 0.13 5,546 866.96 0.15
15.00 0.12 5,496 866.95 0.15
15.50 0.10 5,425 866.92 0.15
16.00 0.09 5,331 866.90 0.15
16.50 0.08 5,222 866.86 0.15
17.00 0.08 5,107 866.83 0.15
17.50 0.08 4,985 866.79 0.14
18.00 0.07 4,859 866.75 0.14
18.50 0.07 4,726 866.71 0.14
19.00 0.06 4,588 866.66 0.14
19.50 0.06 4,445 866.61 0.14
20.00 0.05 4,296 866.57 0.14

ENGINEERINGOAK
HYDROFLOW STORM SEWERS MODEL OUTPUT
10-YEAR, 24-HOUR STORM EVENT

Culvert Report
Hydraflow Express Extension for Autodesk®Civil 3D®by Autodesk,Inc. Thursday,Jun 22 2023
OCS 15 INCH CMP
Invert Elev Dn (ft) = 861.76 Calculations
Pipe Length (ft) = 78.79 Qmin (cfs) = 9.75
Slope (%) = 0.50 Qmax (cfs) = 9.75
Invert Elev Up (ft) = 862.15 Tailwater Elev (ft) = Normal
Rise (in) = 15.0
Shape = Circular Highlighted
Span (in) = 15.0 Qtotal (cfs) = 9.75
No. Barrels = 1 Qpipe (cfs) = 9.75
n-Value = 0.013 Qovertop (cfs) = 0.00
Culvert Type = Circular Corrugate Metal Pipe Veloc Dn (ft/s) = 7.95
Culvert Entrance = Headwall Veloc Up (ft/s) = 7.95
Coeff. K,M,c,Y,k = 0.0078, 2, 0.0379, 0.69, 0.5 HGL Dn (ft) = 863.01
HGL Up (ft) = 864.81
Embankment Hw Elev (ft) = 865.40
Top Elevation (ft) = 869.00 Hw/D (ft) = 2.60
Top Width (ft) = 35.00 Flow Regime = Inlet Control
Crest Width (ft) = 78.00
Elev(It) OCS 15 INCH CMP Hw Depth(ft]
870.00 , 7.85
869.00 6.85
868.00 5.85
867.00 - 4.85
866.00 3.85
865.00 2.85
864.00 1.85
863.00 0.85
862.00 -0.15
861.00 -1.15
860.00 -2.15
0 10 20 30 40 50 60 70 80 90 100 110 120
Circular Culvert HGL Embank
Reach(ft)

Culvert Report
Hydraflow Express Extension for Autodesk®Civil 3D®by Autodesk,Inc. Thursday,Jun 22 2023
24 INCH CMP TO POND
Invert Elev Dn (ft) = 865.00 Calculations
Pipe Length (ft) = 56.61 Qmin (cfs) = 6.28
Slope (%) = 3.52 Qmax (cfs) = 6.28
Invert Elev Up (ft) = 866.99 Tailwater Elev (ft) = Normal
Rise (in) = 24.0
Shape = Circular Highlighted
Span (in) = 24.0 Qtotal (cfs) = 6.28
No. Barrels = 1 Qpipe (cfs) = 6.28
n-Value = 0.013 Qovertop (cfs) = 0.00
Culvert Type = Circular Corrugate Metal Pipe Veloc Dn (ft/s) = 9.34
Culvert Entrance = Headwall Veloc Up (ft/s) = 4.67
Coeff. K,M,c,Y,k = 0.0078, 2, 0.0379, 0.69, 0.5 HGL Dn (ft) = 865.53
HGL Up (ft) = 867.88
Embankment Hw Elev (ft) = 868.21
Top Elevation (ft) = 870.59 Hw/D (ft) = 0.61
Top Width (ft) = 40.00 Flow Regime = Inlet Control
Crest Width (ft) = 56.00
Elev Sii. 24 INCH CMP TO POND Hw Depth(R)
871.00 4.01
870.00 3.01
869.00 2.01
Inlet control
868.00 - 1.01
867.00 0.01
866.00 - -0.99
865.00 f -1.99
864.00 -2.99
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
CircularCulvert HGL Embank
Reach(ft)

ENGINEERINGOAK
SEDIMENT & EROSION CONTROL DESIGN
SEDIMENT BASIN DESIGN
SKIMMER DESIGN
RIP RAP DESIGN

SEDIMENT BASIN CALCULATIONS OAK
UNITED PLATE GLASS EXPANSION
OAK JOB NO.:023-005
F v G . .. F : . I N G
DATE: 6/22/2023 BY: MB ...'Yv.cF.o.U.c«.ernn.x nx
REVISED: RVW: LB -+w�.
FAIRCLOTH SKIMMER TYPE BASIN DESIGN WITH RISER #1
DRAINAGE AREAS/REQ'D STORAGE I it ESTIMATED BASIN SIZE(RECTANGULAR)
Total drainage area(TDA) 1.47 ac Length(ft) Width(ft)
Disturbed area(DA) 1.47 ac Bottom 39 17
Rqd sediment storage 1800xDA I 2646IIcf Top 51 29
BASIN CONFIGURATION I 'PLANNED BASIN SIZE (REFER TO EROSION CONTROL PLAN)
Proposed sediment depth 2.75 ft I Elev. Area(SF) Cumulative Volume(CF)
Depth of flow over spillway 0.25 ft 865 2087 0
Bottom elevation of basin 865.00 msl 866 2669 2378
Skimmer Invert elevation 866.00 msl 867 3311 5368
Sediment Storage elevation 867.75 msl 867.75 3833 8047
Riser crest 867.75 msl 868 4013 9028
Top of Berm 868.00 msl
-
I BASIN EFFICIENCY
Sediment storage required: 2646 cf
Sediment storage provided: 5669 cf
Surface area required: 2732 sf
Surface area provided: 3833 sf

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Rip Rap Apron Design
Project Name: FES-24 INCH
Drainage Specialist: MWB Date: June 22,2023
Checked By: LJB Date: June 22,2023
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter,it is
classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter,it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): N/A
Outlet pipe diameter,Do(in.) 24
Tailwater depth(Feet) 0.0
Tailwater Method To Be Used Min TW(Fig.8.06a)
Discharge(cfs) 6.3
Velocity(ft./s) 9.3
Step 2. Based on the tailwater conditions determined in Step 1,enter Figure 8.06a or Figure 8.06b and
determine the d50 rip rap size and minimum apron length(La). The d50 size is the median stone
size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape,and the apron width at the outlet
end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50,(ft.) 0.5
Minimum apron length,La(ft.) ** 12
Apron width at pipe outlet(ft.) 6
Apron shape W=Do+La
Apron width at outlet end(ft.) 14
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter.Dmax= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,,.
Minimum TW Maximum TW
Max Stone Diameter,dmax(Inches): 9
Apron Thickness(Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron as
straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It may
be necessary to increase the size of the rip rap where protection of the channel side slopes is
necessary. Where overfalls exist at pipe outlets or flows are excessive,a plunge pool should
be considered.

Rip Rap Apron Design
Project Name: FES-OCS
Drainage Specialist: MWB Date: June 22,2023
Checked By: LJB Date: June 22,2023
Step 1. Determine the tailwater depth from the channel characteristics below the pipe outlet for the
design capacity of the pipe. If the tailwater depth is less than half the outlet pipe diameter,it is
classifies as minimum tailwater conditions. If the tailwater is greater than half the pipe
diameter,it is classified as maximum tailwater conditions. Pipes that outlet onto wide flat
areas with no defined channel are assumed to have a minimum tailwater condition unless
reliable flood stage elevations show otherwise.
Rational Method for Flow
Total Drainage Area(Acres): N/A
Outlet pipe diameter,Do(in.) 15
Tailwater depth(Feet) 0.0
Tailwater Method To Be Used Min TW(Fig.8.06a)
Discharge(cfs) 9.8
Velocity(ft./s) 8.0
Step 2. Based on the tailwater conditions determined in Step 1,enter Figure 8.06a or Figure 8.06b and
determine the d50 rip rap size and minimum apron length(La). The d50 size is the median stone
size in a well-graded rip rap apron.
Step 3. Determine the apron width at the pipe outlet,the apron shape,and the apron width at the outlet
end from the same figure used in Step 2.
Minimum TW Maximum TW
Riprap d50,(ft.) 0.5
Minimum apron length,La(ft.) ** 10
Apron width at pipe outlet(ft.) 4
Apron shape W=Do+La
Apron width at outlet end(ft.) 11
**-Minimum Apron Length Is 10 Feet per CLDS 20.23
Step 4. Determine the maximum Stone Diameter.Dmax= 1.5 X d50
Determine the Apron Thickness,Ta= 1.5 X d,,.
Minimum TW Maximum TW
Max Stone Diameter,dmax(Inches): 9
Apron Thickness(Inches): 14
**-Minimum Apron Thickness Is 10 Inches per CLDS 20.23
Step 5. Fit the rip rap apron to the site by making it level for the minimum length La. Extend the
apron farther downstream and along the channel banks until stability is assured. Keep apron as
straight as possible and align it with the flow of the receiving stream. Make any necessary
alignment bends near the pipe outlet so that the entrance into the receiving stream is straight.
Some locations may require lining of the entire channel cross section to assure stability. It may
be necessary to increase the size of the rip rap where protection of the channel side slopes is
necessary. Where overfalls exist at pipe outlets or flows are excessive,a plunge pool should
be considered.

Figure 8.06a: Design of outlet protection from a round pipe flowing full, minimum
tailwater condition (Tw<0.5 diameter)
3 0
Outlet la • Do + La ,
pipe I I , N A , . , .. , 4 t.,,,,,/ •• .
diameter (Do) :: : : ,�;
80 La . 1 . . .. / 1 tp , 411 4
.. th • rAdriP
4? MIMI I ...'-1 - 1-.. ...,efr . I. . ' 40.2..
ii:: ::.:: i:'..:':*:•:' : l_m_ 111 7' :L..'::.:,. '.„..-.° '--" '7. , . : . 1.4,,,,,,,t,/,,,
20 . ...Fit. :.... ...::p..:., _63 •• • .....,a0.1 • . . i...i7i,m.lIlIM.if•w.
—Liidiit w+ter < 0.5Qo II • -„� .
`tea. ] i. • i lii:i: ff> �' •.
o�PQcoSo l '
r j
Yam.
i I �o •I
cz) . 1..serApropr: ro i.„,...4.3. . -.
...„
0,4 4 .44 . 4 . ......._._
:!:::11:::1::::,:: : 1:::1:;-:; • ._. ' .' . . .,1 : : , ,..„..4011/1" " Akid v A,. ..
i• l � .� ��' ... III-•. . ... .:' .i �
illrilli
v _ to _0g =/� � :
v .
______
■11 UI ,
3 14 20 50 100 200 500 1000
Discharge(f13/sec)
Curves may not be extrapolated
Figure 8.06a Design of outlet protection protection horn a round pipe flowing full.minimum tailwater condition(T,,c 0.5 dameter).
RIM 1193 8.063