SW6191004_PN_95396_Multipurpose_Training_Facility_SWM_and_ES_Calcs_Narrative_Rev01_1/22/2020

CIVIL CALCULATIONS
SOTF Multipurpose Training Facility
P N 95396
The civil calculations attached are for the storm water management and erosion
and sediment control analysis.
100% Submittal: 12 July 2019
Revised for SWM Permit SW6191004: 16 January 2020
Prepared by:
(I Stantec
Stantec Consulting Services Inc.
801 Jones Franklin Road, Suite 300
Raleigh, North Carolina, 27606
[phone] //Fax [phone]
CA
:Q SE
4 =
F,y N
/11111W07 1020

TABLE OF CONTENTS
Sediment Erosion Control and Stormwater Management Project
Narrative....................................................................................................................01
NRCS Report..............................................................................................................03
Rip -Rap Outlet Protection Sizing............................................................................07
Water Quality Volume Calcs...................................................................................12
Channel Sizing and Velocity Calcs..........................................................................19
DrainageArea Maps................................................................................................21

Ft. Bragg, SOTF Multi -Purpose Training Facility Project
Sediment Erosion Control and Stormwater Management
Narrative
The proposed project known as Fort Bragg SOTF Multi -Purpose Training Facility
project consists of a new concrete training facility along with access/maintenance
roads, and storm drainage. The new training structure is similar to a walk -out basement
in terms of grading and access. This report presents the sediment and erosion control
and stormwater management calculations for the project.
The property is located on Fort Bragg in Cumberland County, North Carolina with
access to the site from Lamont Road. The project is located in the north/northwest
portion of the compound. The scope of work for the project includes civil site work and
minor electrical site utilities design along with clearing and grubbing of existing trees.
The project is located in a wooded area on the north side of a crowned highpoint which
drains primarily to the north and east with a smaller share of drainage to the southeast.
The site consists primarily of hydrologic Group A soils (see NRCS report) which has
been corroborated with favorable infiltration rates (3.3 in/hr and 2.02 in/hr—see
geotechnical report submitted under separate cover).
SEDIMENT AND EROSION CONTROL
The site sits on a crowned high point with gradual slopes typically less than 6% within
the limits of disturbance (LOD). The primary disturbance activity for the construction of
the facility will be excavation; therefore, the primary means of sediment leaving the site
will be within storm drain systems and in the initial stage of clearing and utility
trenching. The perimeter is protected with a combination of sediment fence, J-hooks,
and sediment fence outlets. The storm drain system will use inlet protection and rip -rap
outlet protection to prevent sediment laden water from leaving site. There is only one
point of entry/exit to the site where a temporary construction entrance/exit is located
(the western most edge of the LOD). A concrete washout station is also provided near
the entrance/exit. All stormwater facilities will be constructed last, once all drainage
areas have been stabilized.
STORMWATER MANAGEMENT
The site has been broken down into two main drainage areas (one for each infiltration
facility) for the purposes of determining the required stormwater management volume
for each infiltration basin. The site has been graded to capture all the impervious areas
either in storm drain systems or surface flow via swales and sheet flow. The impervious
areas consist mainly of the concrete roof/pad of the training facility and the
maintenance/crane access road which is comprised of 12 inches of NCDOT #4
washed stone laid on geotextile fabric. The northwestern portion of the site is captured
primarily through a storm drain network with false sumps at manholes with grated inlet
tops. This network outfalls to an infiltration basin: SWM#2. The northeastern portion of
Page 1 of 27

the site enters SWM #2 via sheet flow. The southeastern portion of the site primarily
enters SWM#2 via a small swale with a small portion entering via an inlet which drains
via 15" RCP (Gov. mandated minimum pipe size) to an outfall. The southwestern
portion of the site drains to a SWM#1, an infiltration trench, which is a graded as a
false sump. A rock weir overflow was designed for this facility to channel the water
through a specific part of the berm such that the overflow would not enter the channel
leading to SWM #2.
Page 2 of 27

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Page 3 of 27

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Page 4 of 27

Hydrologic Soil Group —Cumberland County, North Carolina
Soil Map -
Hydrologic Soil Group
Map unit symbol
Map unit name
Rating
Acres in AOI
Percent of AOI
BaB
Blaney loamy sand, 2 to
8 percent slopes
C
1.0
11.3%
BaD
Blaney loamy sand, 8 to
15 percent slopes
C
0.2
1.9%
TR
Torhunta and Lynn
Haven soils
A/D
0.7
8.1 %
WaB
Wagram loamy sand, 0
to 6 percent slopes
A
6.9
78.6%
Totals for Area of Interest
8.8
100.0%
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive
precipitation from long -duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when
thoroughly wet. These consist mainly of deep, well drained to excessively
drained sands or gravelly sands. These soils have a high rate of water
transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well
drained soils that have moderately fine texture to moderately coarse texture.
These soils have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of
water transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink -swell
potential, soils that have a high water table, soils that have a claypan or clay
layer at or near the surface, and soils that are shallow over nearly impervious
material. These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in
their natural condition are in group D are assigned to dual classes.
USDA Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
2/12/2019
Page 3 of 4
Page 5 of 27

Hydrologic Soil Group —Cumberland County, North Carolina
Soil Map
Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff.- None Specified
Tie -break Rule: Higher
USDA Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
2/12/2019
Page 4 of 4
Page 6 of 27

—
DATE
20190703
DESIGN PHASE
PRELIM
CONSTR
REVISION
RECORD
OTHER
(SPECIFY)
/ X /
PROJECT NAME
Multipurpose Training Facility
P70-77M 0
178451232
Fort Bragg, NC
MTB
UHLUKLU BY
UL5
Storm Outlet Structure - A7
FES No.=
A7
Pipe Dia=
15
in
Q 1 o =
2.76
cfs
Qfull =
4.52
cfs
Vfu l l =
3.7
fps
From Fig. 8.06.b.1:
From Fig. 8.06.b.2:
Zone
Dso
DmAx
Riprap Class
Apron Thickness
Apron Length
Apron Width = 3xDia
Storm Outlet Structure - B2
FES No.=
B2
Pipe Dia=
15
in
Q 1 o =
2.64
cfs
Qfull =
4.80
cfs
Vfu l l =
3.90
fps
From Fig. 8.06.b.1:
From Fig. 8.06.b.2:
s
3
Length
Zone
Dso
DmAx
Riprap Class
Apron Thickness
Apron Length
Apron Width = 3xDia
Q10/Qfull = 0.61
V/Vfu I = 1.05
V = 3.8 fps
= 1
= 4 in
= 6 in
= A
= 12 in
= 5 ft
= 4 ft
Q10/Qfull = 0.55
V/Vfu I = 1.02
V = 4.0 fps
= 1
= 4 in
= 6 in
= A
= 12 in
= 5 ft
= 4 ft
Page 7 of 27

' ' • •
DATE
20190703
DESIGN PHASE
PRELIM
CONSTR / X /
REVISION
RECORD
OTHER
(SPECIFY)
PROJECT NAME
Multipurpose Training Facility
PROJECT NO
178451232
LOCATION
Fort Bragg, NC
BY
MTB
CHECKED BY
DLS
Storm Outlet Structure C-1 and C-2
FES No.= *N/A
Pipe Dia= 12
in
Q 1 o = 2.84
cfs
Qfull = 3.56
cfs
Vfu l l = 4.53
fps
From Fig. 8.06.b.1:
Zone
From Fig. 8.06.b.2:
D50
DMAX
Riprap Class
Apron Thickness
Apron Length
Apron Width = 3xDia
*Culvert Projecting from Fill
Q10/Qfull =
V/Vfu I I =
V=
0.80
1.11
5.0 fps
= 1
= 4 in
= 6 in
= A
= 12 in
= 4 ft
= 3 ft
Page 8 of 27

Channel Report
Hydraflow Express Extension for Autodesk0 AutoCADO Civil 3D0 by Autodesk, Inc.
Stormwater Infiltration #1 Overflow-Q10
Trapezoidal
Bottom Width (ft)
= 10.00
Side Slopes (z:1)
= 3.00, 3.00
Total Depth (ft)
= 0.50
Invert Elev (ft)
= 244.50
Slope (%)
= 1.85
N-Value
= 0.033
Calculations
Compute by:
Known Q
Known Q (cfs)
= 2.84
Elev (ft)
246.00
245.50
245.00
244.50
244.00
2 4 6
Section
8 10
Reach (ft)
Highlighted
Depth (ft)
Q (cfs)
Area (sqft)
Velocity (ft/s)
Wetted Perim (ft)
Crit Depth, Yc (ft)
Top Width (ft)
EGL (ft)
Wednesday, Jul 3 2019
= 0.16
= 2.840
= 1.68
= 1.69
= 11.01
= 0.14
= 10.96
= 0.20
12 14 16
Depth (ft)
1.50
1.00
0.50
ffixere,
-0.50
18
Page 9 of 27

Hydrograph Report
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2019.2
Friday, 06 / 28 / 2019
Hyd. No. 1
Channel 1
Hydrograph type
= Rational
Peak discharge
= 2.864 cfs
Storm frequency
= 10 yrs
Time to peak
= 5 min
Time interval
= 1 min
Hyd. volume
= 859 cuft
Drainage area
= 1.250 ac
Runoff coeff.
= 0.29*
Intensity
= 7.902 in/hr
Tc by User
= 5.00 min
OF Curve
= Pope_AAF_IDF_Hydrographs.J�e/Rec
limb fact
= 1/1
Composite (Area/C) = [(0.950 x 0.38) + (0.300 x 0.03)] / 1.250
Q (cfs)
3.00
rM
1.00
0.00
0 1
— Hyd No. 1
Channel 1
Hyd. No. 1 -- 10 Year
2 3 4 5 6 7 8 9
Q (cfs)
3.00
2.00
1.00
1 0.00
10
Time (min)
Page 10 of 27

Hydrograph Report
2
Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2019.2
Hyd. No. 2
Channel 2
Hydrograph type
= Rational
Peak discharge
Storm frequency
= 10 yrs
Time to peak
Time interval
= 1 min
Hyd. volume
Drainage area
= 0.420 ac
Runoff coeff.
Intensity
= 7.902 in/hr
Tc by User
OF Curve
= Pope_AAF_IDF_Hydrographs.J�e/Rec
limb fact
Composite (Area/C) = [(0.137 x 0.95) + (0.283 x 0.30)] / 0.420
Q (cfs)
2.00
1.00
0.00
0 1
— Hyd No. 2
Channel 2
Hyd. No. 2 -- 10 Year
Friday, 06 / 28 / 2019
= 1.693 cfs
= 5 min
= 508 cuft
= 0.51 *
= 5.00 min
= 1/1
2 3 4 5 6 7 8 9
Q (cfs)
2.00
1.00
N 0.00
10
Time (min)
Page 11 of 27

1 /16/2020
NCDEQ BMP Manual
INFILTRATION BASIN #1 & #2
1.0" Water Quality Volume (WQv)
(ACTUAL DRAINAGE AREA TO SWM DEVICE)
Rv = runoff coefficient (Runoff/Rainfall)
Rv = 0.05 + 0.009( 1 ) Where "I" = % Impervious
("Simple Method" - Schueler, 1987)
WQv = 1.0"RvA
12
Infiltration Basin #1
Fill in Values:
M0718
DA Impervious Area (Ex. & Prop.)
"1" = Percent Impervious of DA
"A" = "DA (Acres)
"Offiste area = 4,261 SF
Answer:
WQv =
0.022
Ac. Ft.
Cubic Feet Required
Cubic Feet Provided
976
1,520
Infiltration Basin #2
Fill in Values:
0.606 DA Impervious Area (Ex. & Prop.)
"1" = 27.3409 Percent Impervious of DA
"A" = 2.215 *DA (Acres)
"Offiste area = 6,045 SF
Answer:
WQv =
0.055
Ac. Ft.
Cubic Feet Required
Cubic Feet Provided
2,381
2,569
= 11 282 SF impervious area
A = Actual Drainage Area to SWM Device
Rv= 0.374732
WQv= 0.37 inches
CN(WQv)= 91.4 Use to comp. Q,--
= 26 380 SF impervious area
A = Actual Drainage Area to SWM Device
Rv= 0.296068
WQv= 0.30 inches
CN(WQv)= 89.3 Use to comp. Q,--
Page 12 of 27

DRAINAGE AREA & IMPERVIOUS AREA
Pre -Development Impervious Area (Within Drainage Areas) Infilt #1 0 SF
Infilt #2 0 SF
Post Development Impervious Area (Prop. & Ex.) (Within Drainage Area)
Infilt #1
11,282 SF
Infilt #2
26,380 SF
Post Development Impervious Area (Prop. & Ex.) (Excudes Gravel)
Infilt #1
2,352 SF
Infilt #2
10,785 SF
Project Limit of Disturbance (Using as Project Area)
LOD
158,994 SF
Pre -Development Impervious Area (Within LOD)
LOD
0 SF
Post Development Impervious Area (Prop. & Ex.) (Within LOD)
LOD
37,662 SF
Post Development Impervious Area (Prop. & Ex.) (Excludes Gravel)
LOD
13,137 SF
1.0" Volume For Project Area (LOD) Using Simple Method
Per Runoff Volume Simple Method NCDEQ Stormwater BMP Manual
PRE -DEVELOPMENT
RVPRE = 0.05 + 0.9 * IA
_ Existing Site Impervious Area
IA Total Area (Project Area)
_ 0
IA 158,994
1A = 0.00
RVPRE = 0.05
POST DEVELOPMENT
RvPosT = 0.05 + 0.9 * 1A
_ Developed Site Impervious Area (Prop. & Ex.)
IA Total Area (Project Area)
37,662
IA_ 158,994
1A = 0.24
RVPosT = 0.26 RvPosT = 0.12
(NO Gravel)
Newly created Impervious area for the Project =
37,662 SF
Page 13 of 27

1.0" VOLUME REQUIRED For Project Area (LOD) Using Simple Method
Simple Method
V = 3630 * P * (RVPOST - RVPRE) * DA
P (1.0") = 1 IN
DA = 158,994 SF
DA = 3.65 AC
V = 3,487 CF = VOLUME REQUIRED FOR PROJECT AREA USING SIMPLE METHOD (DOES NOT FACTOR IN PRE -CONDITIONS IMP. AREA, REMOVES Rvpre FROM EQUATION)
V = 1,648 CF = VOLUME REQUIRED FOR PROJECT AREA USING SIMPLE METHOD (EXCLUDES GRAVEL)
STORMWATER VOLUME SUMMARY CALCULATIONS
TOP OF
INFILTRATION
SURFACE AREA @
DEPTH OF
VOLUME
*VOL.
**INFILTRATIO
TOTAL
TOP OF
***BOTTOM
EMBANK
IMPERVIOUS
BASIN #
BOTTOM
PONDING
VOIDS
N RATE
VOLUME
BASIN
OF BASIN
SHWT
MENT
AREA
PONDING
PONDING
TREATING
(SF)
(FT)
(CF)
(CF)
(IN/HR)
(CF)
(FT)
(FT)
(FT)
(FT)
(SF)
1
724
1.50
1,086
434
3.30
1,520
243.00
240.83
>237.75
244.50
11,282
2
2,855
0.90
2,569
2.02
2,569
223.77
223.44
219.16
224.67
26,380
*Assumes a Void Ratio of 0.4 for the 1.5-2.5 inch speficied stone. Accounts for only the 4 feet of stone does not include pea gravel and sand.
** Based on observation from the geotechnical engineer
SHWT = Seasonal High Water Table
***The bottom of sand filter layer where in -situ infiltration rate occurs
Impervious Area Treating 37,662 sf
Newly created Impervious Area 37,662 sf
1.0" WQV Required, Project Area (LOD) (Simple Method, Pre -Development Conditions NOT Considered) 3,487 cf
1.0" WQV Required, Drainage Areas Only (Simple Method, Pre -Development Conditions NOT Considered) 3,357 cf
1.0" WQV Required, Drainage Areas Only (Simple Method, Pre -Development Conditions NOT Considered, NO Gravel) 1,648 cf
1.0" WQV Provided 4,090 cf
Page 14 of 27

Infiltration Basin #1
SA = DV
(K/1 VFW
DV (Required)= 976.43 cu ft
K= 3.30 in/hr
FS= 2
T= 72 hrs
Min. Surface Area (SA) 1 99
Surface Area Provided = 1 724
Infiltration Basin #2
SA = DV
0.718 *DA (Acre! (K/12/FS*T)
DV (Required)= 2,380.52 cu ft
K= 2.02 in/hr
FS= 2
T= 72 hrs
Min. Surface Area (SA) = 393
Surface Area Provided = 2,855
Page 15 of 27

NC DEQ Draw Down Time:
Infiltration Basin #1
Total Volume Provided:
1,520 cu.ft.
Infiltration Bottom Area:
724 sq ft.
Maximum Release Time:
72 hrs
Overflow Berm Elev:
244.50
Bottom of Basin:
1 243.00
Infiltration Rate:
1 3.30 in/hr
Factor of Safety (FS):
1 2.00
Bottom of Infiltration Basin Elev:
243.00
Draw Down Time for only Infiltration with FS: 15 hrs
Infiltration Basin #2
Total Volume Provided:
2,569 cu.ft.
Infiltration Bottom Area:
2,855 sq ft.
Maximum Release Time:
72 hrs
Overflow Elev:
224.67
Bottom of Basin:
1 223.77
Infiltration Rate:
1 2.02 in/hr
Factor of Safety (FS):
1 2.00
Bottom of Infiltration Basin Elev:
223.77
Draw Down Time for only Infiltration with FS: F 11 hrs
(Boring 1-02)
OK
(Boring 1-01)
Ce77
Page 16 of 27

Tee Consmner
UgWid used:-Wniclpal W9w Depth of 1Y~ 1abke: M, Water Temp ('Pk 0 OF
lest location: 1-121 Depth of OMerred Wirier 26A inches
Cmmramm
tapactty
qu an aingrF
se rI
Z*
Sight rube
1_
'1
MOM
t agr u
q
Flare rate used:
1OS
Hal■ pi2m4W..
2A
irxfics
Stwt Saturatiorc
7d3d
Wirer Fiend:
7
irxheS
Hale Radius: 1.20D Hale GID"m - 33 iruhes
Test
ar
m_
AIM
0
'®
®®®®
Page 17 of 27

T4w rd"Cr
uquld 1lsedt Munk" Water
Test LDuff an: 1-02
Depth t+f WM&f TaMe- �96" WelerTMW4 "FK
Depth Df -D6served Water
d" "�efS now rblrwed: 105 Hole Qiame[er:
vnsfarrts:I
CARC-ity
Ucluici
59 uIQ
€M -um
M[
55 'IF
dd irKhem
14 irwhem
SI�TuErt IL Or, 51Ai15etLPfxb*4: 15,0D iWe1lYHeed: 5 lmhee
tar+ge u c L n
Hole Radrai 1.20D Hale Daplh: 5+6 inthee
FS Q c
Page 18 of 27

1.0" VOLUME REQUIRED For Project Area (LOD) Using Simple Method
Simple Method
V = 3630 * P * (RVPOST - RVPRE) * DA
P (1.0") = 1 IN
DA = 158,994 SF
DA = 3.65 AC
V = 3,487 CF = VOLUME REQUIRED FOR PROJECT AREA USING SIMPLE METHOD (DOES NOT FACTOR IN PRE -CONDITIONS IMP. AREA, REMOVES Rvpre FROM EQUATION)
V = 1,648 CF = VOLUME REQUIRED FOR PROJECT AREA USING SIMPLE METHOD (EXCLUDES GRAVEL)
STORMWATER VOLUME SUMMARY CALCULATIONS
TOP OF
INFILTRATION
SURFACE AREA @
DEPTH OF
VOLUME
*VOL.
**INFILTRATIO
TOTAL
TOP OF
***BOTTOM
EMBANK
IMPERVIOUS
BASIN #
BOTTOM
PONDING
VOIDS
N RATE
VOLUME
BASIN
OF BASIN
SHWT
MENT
AREA
PONDING
PONDING
TREATING
(SF)
(FT)
(CF)
(CF)
(IN/HR)
(CF)
(FT)
(FT)
(FT)
(FT)
(SF)
1
724
1.50
1,086
434
3.30
1,520
243.00
240.83
>237.75
244.50
11,282
2
2,855
0.90
2,569
2.02
2,569
223.77
223.44
219.16
224.67
26,380
*Assumes a Void Ratio of 0.4 for the 1.5-2.5 inch speficied stone. Accounts for only the 4 feet of stone does not include pea gravel and sand.
** Based on observation from the geotechnical engineer
SHWT = Seasonal High Water Table
***The bottom of sand filter layer where in -situ infiltration rate occurs
Impervious Area Treating 37,662 sf
Newly created Impervious Area 37,662 sf
1.0" WQV Required, Project Area (LOD) (Simple Method, Pre -Development Conditions NOT Considered) 3,487 cf
1.0" WQV Required, Drainage Areas Only (Simple Method, Pre -Development Conditions NOT Considered) 3,357 cf
1.0" WQV Required, Drainage Areas Only (Simple Method, Pre -Development Conditions NOT Considered, NO Gravel) 1,648 cf
1.0" WQV Provided 4,090 cf
Page 19 of 27

Infiltration Basin #1
SA = DV
(K/1 VFW
DV (Required)= 976.43 cu ft
K= 3.30 in/hr
FS= 2
T= 72 hrs
Min. Surface Area (SA) 1 99
Surface Area Provided = 1 724
Infiltration Basin #2
SA = DV
0.718 *DA (Acre! (K/12/FS*T)
DV (Required)= 2,380.52 cu ft
K= 2.02 in/hr
FS= 2
T= 72 hrs
Min. Surface Area (SA) = 393
Surface Area Provided = 2,855
Page 20 of 27

NC DEQ Draw Down Time:
Infiltration Basin #1
Total Volume Provided:
1,520 cu.ft.
Infiltration Bottom Area:
724 sq ft.
Maximum Release Time:
72 hrs
Overflow Berm Elev:
244.50
Bottom of Basin:
1 243.00
Infiltration Rate:
1 3.30 in/hr
Factor of Safety (FS):
1 2.00
Bottom of Infiltration Basin Elev:
243.00
Draw Down Time for only Infiltration with FS: 15 hrs
Infiltration Basin #2
Total Volume Provided:
2,569 cu.ft.
Infiltration Bottom Area:
2,855 sq ft.
Maximum Release Time:
72 hrs
Overflow Elev:
224.67
Bottom of Basin:
1 223.77
Infiltration Rate:
1 2.02 in/hr
Factor of Safety (FS):
1 2.00
Bottom of Infiltration Basin Elev:
223.77
Draw Down Time for only Infiltration with FS: F 11 hrs
(Boring 1-02)
OK
(Boring 1-01)
Ce77
Page 21 of 27

Tee Consmner
Liquid used:-uniclpal W9w Depth of 1Y~ 1abke: M, Water Temp ('Pk 0 OF
lest location: 1-121 Depth of OMerred Wirier 26A inches
Cmmramm
tapactty
qu an aingrF
se rI
Z*
Sight rube
1_
'1
MOM
t agr u
q
Flare rate used:
1OS
Hal■ pi2m4W..
2A
irxfics
Stwt Saturatiorc
7d3d
Wirer Fiend:
7
irxheS
Hale Radius: 1.20D Hale GID"m - 33 iruhes
Test
ar
m_
AIM
0
'®
®®®®
Page 22 of 27

T4w rd"Cr
uquld 1lsedt Munk" Water
Test LDuff an: 1-02
Depth t+f WM&f TaMe- �96" WelerTMW4 "FK
Depth Df -D6served Water
d" "�efS now rblrwed: 105 Hole Qiame[er:
vnsfarrts:I
CARC-ity
Ucluici
59 uIQ
€M -um
M[
55 'IF
dd irKhem
14 irwhem
SI�TuErt IL Or, 51Ai15etLPfxb*4: 15,0D iW81lYHeed: 5 lmhee
tar+ge u c L n
Hole Radrai 1.20D Hale Daplh: 5+6 inthee
FS Q c
Page 23 of 27

Channel Report
Hydraflow Express Extension for Autodesk0 AutoCADO Civil 3D0 by Autodesk, Inc.
Channel 1 10 Yr Storm Rational Method
Triangular
Side Slopes (z:1)
= 12.00, 12.00
Total Depth (ft)
= 0.60
Invert Elev (ft)
= 244.50
Slope (%)
= 0.46
N-Value
= 0.040
Calculations
Compute by:
Known Q
Known Q (cfs)
= 2.86
Elev (ft) Section
246.00
245.50
245.00
244.50
244.00
Highlighted
Depth (ft)
Q (cfs)
Area (sqft)
Velocity (ft/s)
Wetted Perim (ft)
Crit Depth, Yc (ft)
Top Width (ft)
EGL (ft)
Wednesday, Jul 3 2019
= 0.50
= 2.860
= 3.00
= 0.95
= 12.04
= 0.33
= 12.00
= 0.51
2 4 6 8 10 12 14 16 18 20
Reach (ft) Page 24 of 27
Depth (ft)
1.50
1.00
0.50
ffixere,
_n tin

Channel Report
Hydraflow Express Extension for Autodesk0 AutoCADO Civil 3D0 by Autodesk, Inc.
Channel 2 10-Yr Storm Rational Method
Triangular
Side Slopes (z:1)
= 4.00, 4.00
Total Depth (ft)
= 0.50
Invert Elev (ft)
= 225.50
Slope (%)
= 4.84
N-Value
= 0.040
Calculations
Compute by:
Known Q
Known Q (cfs)
= 1.69
Elev (ft)
227.00
226.50
226.00
225.50
225.00
Section
Highlighted
Depth (ft)
Q (cfs)
Area (sqft)
Velocity (ft/s)
Wetted Perim (ft)
Crit Depth, Yc (ft)
Top Width (ft)
EGL (ft)
Friday, Jun 28 2019
= 0.40
= 1.690
= 0.64
= 2.64
= 3.30
= 0.41
= 3.20
= 0.51
.5 1 1.5 2 2.5 3 3.5 4 4.5
Reach (ft) Page 25 of 27
Depth (ft)
1.50
1.00
0.50
-0.50

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LOD
LOD A OD LOD
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STORMWATER MANAGEMENT DRAINAGE AREAS
WM10 SCALE:1"=30'
0 30 00
SCALE IN FEET
E %
(9
SWM PERMIT SET
I I
US Army Corps
of Engineers
w
0
z
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w
z
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SWM101
Page 26 of 27

\�_ -_L -
- r r- - -- - , - ---- - -ter \ 1
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Lo ��L01 r - 241��-�
�242
� � ✓ �� � 242 - - - -2 43 242.1
__243'- awn �.13 1
♦ _ - 243'-3 ,1,41 �� 7 4 7 �� $
-24
A1� D 15"RCP _ 14� 1
A r CLASSIVS233.95 2A29 o „14
o 8
45-� 14
246' _ � � 43� � 5 \� 15 � 12 ��0, 1
33 „DIP 7 24 4\ "'� �I 2
232.5 235 233.6) �7a 2 02J
+247.0'A 1 ( 240 CLOD - _ w ✓ ✓��
13 /O � 2� l ✓ j�
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VIC H A t# +24.3' �Qs v� 2455 Art
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2
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LLOD�i 2
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Sp 12" RC
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j 5 245.36
BLDG •. E 246.
g 1,66 aQ ©X243
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o �-+ �
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(J-) STORM DRAIN AND CHANNEL DRAINAGE AREAS
SCALE: V=30'
o an ao
SCALE IN FEET
goo �- ) •.
LOD
' LOD
245.5I
245.5 ,
�;I/ \
FFN>=2:
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STORM DRAINAGE SCHEDULE
CONTINUED �
STORM DRAINAGE SCHEDULE -CONTINUED
9-
206
h=
21
1-
7.92
INLET
INLET
INLET
Cc
INLET
TOTAL
INLET
PIPE
Tc
TIME
Cc
RUNOFF
q
q
SIDE-
CAPACITY
SEGMENT
UPPER
LOWER
UPSTREAM
TOP
PIPE
'..
FROM
TO
AREA
AREA
IMPERVIOUS
RUNOF=
DISCHARGE
AREAS
TIME
TIME
OF GONG.
INTENSITY
COEFF_
DISCHARGE
STREAM
SLOPE
DIA.
(FULL)
V FULL
LENGTH
TIME
INV.
INV.
ELEV.
COVER
(SF)
(AC)
(%)
COEFF.
(CFS)
(AC)
(MIN)
(MINI
(MIN)
(IN/HR)
(CFS}
ICES)
(IN)
(CFS)
(FPS)
(FT)
(MIN)
(FT)
(FT)
(FT)
(FT)
''.. AO
Al
7.324
0.17
25
0.46
0.81
0.17
5.00
0.00
5.00
7.92
0.48
0.61
0.00
0.0054
15
4.8
3.9
48
0.21
227.88
227.60
23205
2.83
''.. All
A2
19.054
0.44
27
0.47
1.64
0.44
5.00
0.00
5.00
7.92
0.47
1.64
0.00
0.0054
15
4.7
3.8
112
0.49
227.50
226.90
231.80
2,94
''.. A2
A3
2.296
0.05
45
0.59
0.25
0.49
5.00
0.49
6.49
7.78
0.19
1.85
0.00
0.0037
15
3.9
3.2
68
0.36
226.80
226.55
213.90
15.74
A3
A4
2..374
0.05
39
0.56
0.24
0.54
5.00
0.84
6.84
7.67
0.49
2.06
0.00
0.0041
15
4.1
3.4
86
0.43
226.45
226. 10
244.80
16.99
A4
A5
2 850
0.07
21
0.43
0.22
0.61
5.00
1.27
6.27
7.55
0.49
2.24
0.00
0.0052
15
4.7
3.8
77
0.34
226.10
225.70
243.80
16.34
'.. A5
A6
0
0.00
0.30
0.00
0.61
5.00
1.81
6.61
748
0.4S
2.22
0.00
0.004,
15
4.3
3.5
Si
0.44
225. 60
225.20
241.70
14.74
AS
A7
0
0.00
0.30
0.00
0,61
5,00
2,04
7.04
7.35
0,49
2.18
0.00
0,0049
15
4,5
3.7
102
0.45
225.10
224,60
236.00
9.54
'.. 61
32
13,963
0.32
10
0.37
0.93
0,32
5,00
0,00
5.00
7.92
0,31
0.93
0.00
0,0056
15
4,8
3.9
270
1.15
227.50
226,00
232.65
3.79
''.. Ci
C2
27,655
0.63
41
0.57
234
0.63
5.00
0.00
5.00
7.92
0.57
2.84
0.00
0.0100
12
3.6
4.5
50
0.18
243.50
243.00
246.50
1.91
SWM PERMIT SET
I I
US Army Corps
of Engineers
w
0
z
0
a
U
w
0
Y
K
SHEET ID
SWM 102
Page 27 of 27