SW3190201_O'Reilly Wingate, NC Stormwater Report_20190520

BOHLER
E N G I N E E I I N G
STORMWATER MANAGEMENT REPORT
O'REILLY - WINGATE, NC (WGT)
PREPARED FOR:
O'REILLY AUTO PARTS
233 SOUTH PATTERSON AVE.
SPRINGFIELD, MO 65802
BEPC #NCC 182114
November 28th, 2018
Revised: May 17th, 2019
PREPARED BY:
BOHLER ENGINEERING, NC, PLLC
1927 S. TYRON ST. SUITE 310
CHARLOTTE, NC 28203
[phone]
NORTH CAROLINA LICENSE #043610
MIKE THEBERGE, P.E.
PROFESSIONAL CERTIFICATION: I HEREBY CERTIFY THAT THESE DOCUMENTS WERE PREPARED OR APPROVED BY ME, AND
THAT I AM A DULY LICENSED REGISTERED ENGINEER UNDER THE LAWS OF THE STATE OF NORTH CAROLINA, LICENSE
NUMBER 0343610
CIVIL & CONSULTING ENGINEERS- SURVEYORS•TRAFFIC CONSULTANTS -ENVIRONMENTAL & GEOTECHNICAL ENGINEERS
www.bohlereng.com

Table of Contents
GeneralProject Description................................................................................................................. 3
General Project Overview and Existing Conditions............................................................................3
Stormwater Requirements and Design Overview.............................................................................3
Stormwater Management and BMP Calculations................................................................................ 3
Stormwater Control Measure Summary....................................................................................3
Appendix............................................................................................................................................... 5
HydroCADOutput..........................................................................................................................
Pre/Post Development Drainage Map..............................................................................................
OnsitePipe Calculations.................................................................................................................
RainfallData.................................................................................................................................
2

General Project Description
GENERAL PROJECT OVERVIEW AND EXISTING CONDITIONS
The subject site is located at 3628 West Highway 74, in Wingate, North Carolina. The existing
land currently contains a residential home as well as a freestanding ATM. The site currently has
a combination of gravel, grass, tree, and impervious cover (roof, concrete, etc.). The site drains
north to south. Runoff from US-74 enters the site via an existing 18" RCP before surface
draining to the point of analysis located at the southern edge of the site. Surface runoff from
Chaney Street is also captured at the point of analysis.
The proposed project is for development of an O'Reilly Auto Parts store with associated site
improvements.
STORMWATER REQUIREMENTS AND DESIGN OVERVIEW
The project is located within the Town of Wingate and will be subject to NCDEQ stormwater
requirements.
The stormwater control measure (SCM) chosen for this project is Bioretention, which is a
primary SCM, designed to conform to North Carolina state regulations 15A NCAC 02H .1001 -
15A NCAC 02H .1045 and 15A NCAC 02H .1052. The minimum design criteria (MDC) for the
SCM, can be found online at:
https://deq.nc.gov/about/divisions/energy-mineral-land-resources/energy-mineral-land-
rules/stormwater-program-rules
Stormwater Management and BMP Calculations
STORMWATER CONTROL MEASURE SUMMARY
The method in which the twelve Minimum Design Criteria are being met are described below.
MDC #1: Seasonally High Water Table Report included in this submission showing no
indication on SHWT to a depth of 37" below existing grade or roughly at 557'. The bottom of
the bioretention cell is at 559'.
MDC #2: Runoff from the 1 inch 24-hour storm was routed through the system via Hydrocad.
The maximum ponding elevation is shown to be 562.48' thus satisfying the maximum ponding
requirement of 12".
MDC #3: Peak runoff attenuation was obtained at the engineer's discretion per MDC #3.
Runoff from both the 1-year 24-hour and 10-year 24-hour storm events were attenuated. An
outlet control box was added at the bypass water culvert (structure Al on plans) in order to
attain the peak flow reduction. Results can be seen below:
Pre -development Qi: 6.63 cfs
Post -development Q1: 6.27 cfs

Pre -development Q1o: 13.68 cfs
Post -development Qio: 12.13 cfs
MDC#4: An underdrain with internal water storage set at elevation 560.0' is specified, meeting
the 18" minimum below top of media.
MDC#5: Bioretention contains herbaceous plants and meets the 30" minimum depth.
MDC #6: Note on stormwater details outlines the required makeup of the bioretention media.
MDC #7: Site is located within the Yadkin Pee -Dee River basin which is considered Nutrient
Sensitive Waters (NSW). Because of this, note is included within the stormwater details that the
P-index of the media shall not exceed 30.
MDC #8: Note included in stormwater details that media shall not be mechanically compacted.
MDC #9: Media shall be maintained per requirement.
MDC#10: Landscape plan shows bioretention plantings, which have been selected per
approved species list.
MDC#11: Cypress mulch specified within bioretention cell.
MDC#12: Underdrain cleanout shown in stormwater details.
Note: Total built upon area for the project is 0.70 acres. Although only 0.62 acres of the BUA is
being directed towards the SCM, the system has been sized to meet the MDC for the runoff
volume generated from 0.70 acres BUA, thus satisfying 15A NCAC 02H .1002 (43).
All associated calculations have been provided within the Appendix section of this report.
4

1S
Pre -Development
Byl iass
2S � 3L
Pre -Development Pre -Development POI
4S
gS
Post-Devel
ment
Post- evelopment
Bypass A Im
rvious
gyp ss A Pervious
5S
8S
Post-Devel pment
Impervi us
Post- evelopment
envious
8P
Subcat Reach Pon Link
Bioretention
Bypass Det ntion Swale
� 6L 7S
Post -Development POI Post -Development
Bypass B

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 2
Time span=0.00-48.00 hrs, dt=0.01 hrs, 4801 points
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method
Subcatchment 1S: Pre -Development Runoff Area=0.620 ac 93.55% Impervious Runoff Depth=0.71"
Tc=5.0 min CN=97 Runoff=0.77 cfs 0.036 of
Subcatchment 2S: Pre -Development Runoff Area=1.390 ac 25.18% Impervious Runoff Depth=0.15"
Flow Length=349' Tc=5.0 min CN=84 Runoff=0.33 cfs 0.018 of
Subcatchment 4S: Post -Development Runoff Area=0.820 ac 100.00% Impervious Runoff Depth=0.79"
Tc=5.0 min CN=98 Runoff=1.11 cfs 0.054 of
Subcatchment 5S: Post -Development Runoff Area=0.620 ac 100.00% Impervious Runoff Depth=0.79"
Tc=5.0 min CN=98 Runoff=0.84 cfs 0.041 of
Subcatchment 7S: Post -Development Runoff Area=0.083 ac 3.61 % Impervious Runoff Depth=0.08"
Tc=5.0 min CN=80 Runoff=0.01 cfs 0.001 of
Subcatchment 8S: Post -Development Runoff Area=0.290 ac 0.00% Impervious Runoff Depth=0.07"
Tc=5.0 min CN=79 Runoff=0.02 cfs 0.002 of
Subcatchment 9S: Post -Development Runoff Area=0.190 ac 0.00% Impervious Runoff Depth=0.07"
Tc=5.0 min CN=79 Runoff=0.01 cfs 0.001 of
Pond 7P: Bioretention Peak Elev=562.48' Storage=0.022 of Inflow=0.85 cfs 0.043 of
Discarded=0.03 cfs 0.043 of Primary=0.00 cfs 0.000 of Outflow=0.03 cfs 0.043 of
Pond 8P: Bypass Detention Swale Peak Elev=561.00' Storage=0.000 of Inflow=1.11 cfs 0.055 of
Outflow=1.11 cfs 0.055 of
Link 3L: Pre -Development POI
Link 6L: Post -Development POI
Inflow=1.09 cfs 0.054 of
Primary=1.09 cfs 0.054 of
Inflow=1.12 cfs 0.056 of
Primary=1.12 cfs 0.056 of
Total Runoff Area = 4.013 ac Runoff Volume = 0.152 of Average Runoff Depth = 0.46"
40.87% Pervious = 1.640 ac 59.13% Impervious = 2.373 ac

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 3
Summary for Subcatchment 1S: Pre -Development Bypass
Runoff = 0.77 cfs @ 11.96 hrs, Volume= 0.036 af, Depth= 0.71"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN Description
0.040 79 50-75% Grass cover, Fair, HSG C
0.580 98 Paved parking, HSG C
0.620 97 Weighted Average
0.040 6.45% Pervious Area
0.580 93.55% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
0.
0.75
0.7 --
0.65
0.6
0.55
a 0.5
0.45
0 0.4
LL ----
0.35
0.25
0.2
0.15
0.1
0.05
Subcatchment 1S: Pre -Development Bypass
Hydrograph
Type 11 24- r
1 inch 24-hr Rainfall=1.00"-
Runoff Area=0.620 ac
Runoff Volume=0.036 of
Runoff Depth=0.717
rc=5.0 mien
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
■ Runoff

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 4
Summary for Subcatchment 2S: Pre -Development
Runoff = 0.33 cfs @ 11.98 hrs, Volume= 0.018 af, Depth= 0.15"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac)
CN
Description
0.350
98
Paved parking, HSG C
1.040
79
50-75% Grass cover, Fair, HSG C
1.390
84
Weighted Average
1.040
74.82% Pervious Area
0.350
25.18% Impervious Area
Tc
Length
Slope
Velocity
Capacity Description
(min)
(feet)
(ft/ft)
(ft/sec)
(cfs)
1.0
77
0.0220
1.27
Sheet Flow,
n= 0.013 P2= 3.64"
1.1
185
0.0300
2.79
Shallow Concentrated Flow,
Unpaved Kv= 16.1 fps
1.0
87
0.0400
1.41
8.46 Channel Flow,
Area= 6.0 sf Perim= 10.0' r= 0.60'
n= 0.150 Sheet flow over Short Grass
1.9
Direct Entry, Time added to reach min Tc
5.0 349 Total
Subcatchment 2S: Pre -Development
Hydrograph
0.36
--r-----r--r --
0.34 0.33 cfs
0.32 Type II 24-hr
03 inch 24-hr Rainfall=1.00"
0.28 ---1--1------------- -i--
0.26 Runoff Area=1.390 a,c
0.24 ----------Runo f-Volume=O-018 of
0.22
° 2 Runoff Depth=0.15"
0 018 Flow Length=349'
ti 0.16
014 �Tc=5.0 min
0.12 ---- CN=84
0.08
0.06
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
■ Runoff

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 5
Summary for Subcatchment 4S: Post -Development Bypass A Impervious
Runoff = 1.11 cfs @ 11.96 hrs, Volume= 0.054 af, Depth= 0.79"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN Description
0.820 98 Paved parking, HSG C
0.820 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 4S: Post -Development Bypass A Impervious
Hydrograph
❑ Runoff
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 6
Summary for Subcatchment 5S: Post -Development Impervious
Runoff = 0.84 cfs @ 11.96 hrs, Volume= 0.041 af, Depth= 0.79"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN Description
0.620 98 Paved parking, HSG C
0.620 100.00% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 5S: Post -Development Impervious
Hydrograph
0.9
0.84 cfs
0.85 _ __ __ _ _
0.8 - - - ------ ype11�4=1�1`
0.75 ----------' inch_24lhrRainfall__=_1.00"0.7
-
Runoff Area=0.620 ac
0.6 - -Runoff Volume=_0.041-af
0.55 ------Runoff De th=0.79`-
e`�i 0.5
o.4s Tc=5.0 min
LL 0.4
CN=98
0.35 ----
0.3 - - -
0.2
0.15
0.1 -- - - - - - -- -
0.05
0
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
■ Runoff

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 7
Summary for Subcatchment 7S: Post -Development Bypass B
Runoff = 0.01 cfs @ 12.00 hrs, Volume= 0.001 af, Depth= 0.08"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN
Description
0.003 98
Paved parking, HSG C
0.080 79
50-75% Grass cover, Fair, HSG C
0.083 80
Weighted Average
0.080
96.39% Pervious Area
0.003
3.61% Impervious Area
Tc Length
Slope Velocity Capacity Description
(min) (feet)
(ft/ft) (ft/sec) (cfs)
5.0
Direct Entry,
Subcatchment 7S: Post -Development Bypass B
Hydrograph
0.007 ■Runoff
0 0 ors
0 007 Type II-24-Itr- -
0.006
0006 1 inch 24-hr Rainfall=1.00"
0.005 Runoff Area=0.083 ac
0.005 Runoff_Volume=0.001 of
w 0004--Runoff Depth=0.08"
0.004 '
3 Tc=5.0 min
0.003
CN=80
0.003 ' '
0.002
0.002
0.001
0.001
0.000
0
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 8
Summary for Subcatchment 8S: Post -Development Pervious
Runoff = 0.02 cfs @ 12.01 hrs, Volume= 0.002 af, Depth= 0.07"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN Description
0.290 79 50-75% Grass cover, Fair, HSG C
0.290 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 8S: Post -Development Pervious
Hydrograph
0.018
0.017
0.02
cfs
0.016
Type II 24-hr
0.015
1 inch 24-hr Rainfall=1.00"
0.014
Runoff Area-0.290
0.013
ac
0.012
Runoff Volume=0.002 of
0.011
--------------- --------- I -------- -------- --
w 0.01
_ _ - - - Runoff _Depth=0.07" -
s 0.009
---------------------- -----Tom'=5.0 min
° 0.008
CN=79 -
0 007
0.006
-
0.005
0.004
LMM
0.003
0.002
0.001
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
❑ Runoff

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 9
Summary for Subcatchment 9S: Post -Development Bypass A Pervious
Runoff = 0.01 cfs @ 12.01 hrs, Volume= 0.001 af, Depth= 0.07"
Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 1 inch 24-hr Rainfall=1.00"
Area (ac) CN Description
0.190 79 50-75% Grass cover, Fair, HSG C
0.190 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
5.0 Direct Entry,
Subcatchment 9S: Post -Development Bypass A Pervious
Hydrograph
0.011
0.011
0.01
cfs
0.01
Type II 24-hr
0.01
0.009
1 inch 24-hr Rainfall=1.00"
0.009
0.008
Runoff Area=0.190 ac
0.008
Runoff Volume=0.001
0.007
of
w 0.006
Runoff Depth=0.07"
3 0006
Tc=5.0 min
0 0.005
LL 0005
CN=79
0.004
0.004
0.003
0.003
0.002
0.002
0.001
-----'----
-'---'-----'---'---
0.001
-------
-+--+----
0.000
0
0 2 4 6 8 10 12
14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
❑ Runoff

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 10
Summary for Pond 7P: Bioretention
Inflow Area =
0.910 ac,
68.13% Impervious, Inflow Depth = 0.56" for 1 inch 24-hr event
Inflow =
0.85 cfs @
11.96 hrs,
Volume= 0.043 of
Outflow =
0.03 cfs @
13.36 hrs,
Volume= 0.043 af, Atten= 96%, Lag= 83.8 min
Discarded =
0.03 cfs @
13.36 hrs,
Volume= 0.043 of
Primary =
0.00 cfs @
0.00 hrs,
Volume= 0.000 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Peak Elev= 562.48' @ 13.36 hrs Surf.Area= 0.034 ac Storage= 0.022 of
Plug -Flow detention time= (not calculated: outflow precedes inflow)
Center -of -Mass det. time= 306.6 min ( 1,097.5 - 790.9 )
Volume Invert Avail.Storage Storage Description
#1 561.50' 0.043 of Storage Above Media (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
561.50 0.009 0.000 0.000
562.00 0.024 0.008 0.008
563.00 0.045 0.035 0.043
Device Routing Invert Outlet Devices
#1 Primary 559.00' 15.0" Round Culvert A
L= 24.0' CMP, square edge headwall, Ke= 0.500
Inlet / Outlet Invert= 559.00' / 559.00' S= 0.0000 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Discarded 561.50' 1.000 in/hr Exfiltration Through Media over Surface area
#3 Device 1 562.50' 12.0' long Top of Riser Box 0 End Contraction(s)
Discarded OutFlow Max=0.03 cfs @ 13.36 hrs HW=562.48' (Free Discharge)
L2=Exfiltration Through Media (Exfiltration Controls 0.03 cfs)
Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=561.50' TW=0.00' (Dynamic Tailwater)
L1=Culvert A (Passes 0.00 cfs of 7.67 cfs potential flow)
L3=Top of Riser Box ( Controls 0.00 cfs)

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 11
Pond 7P: Bioretention
Hydrograph
0.85 cfs
— L — — L — — L — J — — L — —' — — L — J — — L — J — — L — J — -
- -- -,
--- --- ---; - rr�ftOvA'reraTfly91iireC: -
---- - -- ---- - -- ----------------- --r----
0.9
0.85
=-,--; -_
-- ------'-- Peak Elev=562-.48�
0.8
Storage=0.022 of
0.75
0.7
0.65
0.6
W 0.55
0.5
0.45
e
a 0.4
0.35
0.3
0.25
0.2
0.15
-
0.03 cfs
0.1
0.03 cfs
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
M
Less than 1' stage
above media and
below too of box

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 12
Summary for Pond 8P: Bypass Detention Swale
Inflow Area = 1.010 ac, 81.19% Impervious, Inflow Depth = 0.66" for 1 inch 24-hr event
Inflow = 1.11 cfs @ 11.96 hrs, Volume= 0.055 of
Outflow = 1.11 cfs @ 11.96 hrs, Volume= 0.055 af, Atten= 0%, Lag= 0.0 min
Primary = 1.11 cfs @ 11.96 hrs, Volume= 0.055 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Peak Elev= 561.00' @ 11.96 hrs Surf.Area= 0.005 ac Storage= 0.000 of
Plug -Flow detention time= (not calculated: outflow precedes inflow)
Center -of -Mass det. time= 0.0 min ( 787.3 - 787.3 )
Volume Invert Avail.Storage Storage Description
#1 561.00' 0.057 of Custom Stage Data (Prismatic) Listed below (Recalc)
Elevation Surf.Area Inc.Store Cum.Store
(feet) (acres) (acre-feet) (acre-feet)
561.00 0.005 0.000 0.000
562.00 0.028 0.016 0.016
563.00 0.054 0.041 0.057
Device Routing Invert Outlet Devices
#1 Primary 560.25' 15.0" Round Culvert
L= 59.5' Box, 0° wingwalls, square crown edge, Ke= 0.700
Inlet / Outlet Invert= 560.25' / 559.93' S= 0.0054 '/' Cc= 0.900
n= 0.013, Flow Area= 1.23 sf
#2 Device 1 562.50' 6.0' long Sharp -Crested Rectangular Weir 2 End Contraction(s)
#3 Device 1 560.25' 10.0" Vert. Orifice/Grate C= 0.600
Primary OutFlow Max=1.52 cfs @ 11.96 hrs HW=561.00' TW=0.00' (Dynamic Tailwater)
L1=Culvert (Passes 1.52 cfs of 1.71 cfs potential flow)
L2=Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)
3=Orifice/G rate
(Orifice Controls 1.52 cfs @ 2.95 fps)

190517 - Wingate BMP Calcs Type 1124-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 13
Pond 8P: Bypass Detention Swale
Hydrograph
Inflow
❑ Primary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 14
Summary for Link 3L: Pre -Development POI
Inflow Area = 2.010 ac, 46.27% Impervious, Inflow Depth = 0.32" for 1 inch 24-hr event
Inflow = 1.09 cfs @ 11.97 hrs, Volume= 0.054 of
Primary = 1.09 cfs @ 11.97 hrs, Volume= 0.054 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
w
3
0
LL
Link 3L: Pre -Development POI
Hydrograph
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
❑ Inflow
❑ Primary

190517 - Wingate BMP Calcs Type 11 24-hr 1 inch 24-hr Rainfall= 1. 00"
Prepared by Bohler Engineering NC, PLLC Printed 5/17/2019
HydroCADO 10.00-20 s/n 08311 © 2017 HydroCAD Software Solutions LLC Page 15
Summary for Link 6L: Post -Development POI
Inflow Area = 2.003 ac, 72.04% Impervious, Inflow Depth = 0.33" for 1 inch 24-hr event
Inflow = 1.12 cfs @ 11.96 hrs, Volume= 0.056 of
Primary = 1.12 cfs @ 11.96 hrs, Volume= 0.056 af, Atten= 0%, Lag= 0.0 min
Primary outflow = Inflow, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
w
3
0
LL
Link 6L: Post -Development POI
Hydrograph
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
❑ Inflow
❑ Primary

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PRE
1 DEVELOPED DRAINAGE PLAN
C3.8 SCALE: 1" = 30'
KNOW WHAT'S BELOW
ALWAYS CALL 811
BEFORE YOU DIG
It's fast. It's free. It's the law.
30 15 7.5 0 30
1 "= 30'
-----------------,__--
-_-.567 ------
a— —a— — TIME OF CONCENTRATION PATH O O O O O EXISTING IMPERVIOUS AREAS
00000
1 TIME OF CONCENTRATION EXISTING MANAGED TURF
SEGMENTS
O O O 00000000
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2 POST DEVELOPED DRAINAGE PLAN
C3.8 SCALE: V = 30'
THE PROPOSED PROJECT IS FOR DEVELOPMENT OF AN EXISTING TRACT OF LAND TO CONSTRUCT AN O'REILLY AUTO PARTS STORE WITH ASSOCIATED SITE
MDC #3: PEAK RUNOFF ATTENUATION WAS OBTAINED AT THE ENGINEERS DISCRETION PER MDC #3. RUNOFF FROM THE 1-YEAR & 10-YEAR 24-HOUR STORM EVENT WAS
IMPROVEMENTS.
ATTENUATED AND THE RESULTS CAN BE SEEN BELOW:
THE EXISTING LAND CURRENTLY CONTAINS A RESIDENTIAL HOME AS WELL AS A FREESTANDING ATM. THE SITE CURRENTLY HAS A COMBINATION OF GRAVEL, GRASS,
PRE -DEVELOPMENT Q1: 6.63 CFS
TREE, AND IMPERVIOUS COVER (ROOF, CONCRETE, ETC.). THE SITE DRAINS NORTH TO SOUTH. RUNOFF FROM US-74 ENTERS THE SITE VIA AN EXISTING 18" RCP BEFORE
POST -DEVELOPMENT Q1: 6.49 CFS
SURFACE DRAINING TO THE POINT OF ANALYSIS LOCATED AT THE SOUTHERN EDGE OF THE SITE. SURFACE RUNOFF FROM CHANEY STREET IS ALSO CAPTURED AT THE
PRE -DEVELOPMENT Q10: 13.68
POINT OF ANALYSIS.
POST -DEVELOPMENT Q10: 13.57
THE STORMWATER CONTROL MEASURE (SCM) CHOSEN FOR THIS PROJECT IS BIORETENTION, WHICH IS A PRIMARY SCM, DESIGNED TO CONFORM TO NORTH CAROLINA
MDC #4 - #12: CRITERIA HAS BEEN MET. FURTHER INFORMATION CAN BE FOUND WITHIN THE STORWMATER CALCULATION REPORT AS WELL AS THE STORMWATER
STATE REGULATIONS 15A NCAC 02H .1001 - 15A NCAC 02H .1045 AND 15A NCAC 02H .1052. THE MINIMUM DESIGN CRITERIA (MDC) FOR THE SCM, CAN BE FOUND ONLINE AT:
SYSTEM DETAILS.
HTTPS://DEQ.NC.GOV/ABOUT/DIVISIONS/ENERGY-MINERAL-LAND-RESOURCES/ENERGY-M IN ERAL-LAND-RULES/STORMWATER-PROGRAM-RULES
TOTAL BUILT UPON AREA FOR THE PROJECT IS 0.70 ACRES. ALTHOUGH ONLY 0.65 ACRES OF THE BUA IS BEING DIRECTED TOWARDS THE SCM, THE SYSTEM HAS BEEN
STORMWATER CONTROL MEASURE (SCM) NARRATIVE
SIZED TO MEET THE MDC FOR THE RUNOFF VOLUME GENERATED FROM 0.70 ACRES BUA, THUS SATISFYING 15A NCAC 02H .1002 (43).
MDC #1: A SEASONALLY HIGH WATER TABLE ANALYSIS IS PENDING, HOWEVER IT IS ASSUMED THAT THE HIGH WATER TABLE WILL BE DEEP ENOUGH THAT THE PROVIDED
CONCLUSION
ELEVATIONS MEET THE REQUIREMENTS.
MDC #2: RUNOFF FROM THE 1 INCH 24-HOUR STORM WAS ROUTED THROUGH THE SYSTEM VIA HYDROCAD. THE MAXIMUM PONDING ELEVATION IS SHOWN TO BE 561.77,
SINCE THE MINIMUM DESIGN CRITERIA ARE BEING MET, IT IS THE OPINION OF THE ENGINEER THAT THE STORWMATER MANAGEMENT REQUIREMENTS ARE SATISFIED
WHICH IS 0.27' ABOVE THE TOP OF THE MEDIA ELEVATION THUS SATISFYING THE MAXIMUM PONDING REQUIREMENT OR 12".
FOR THIS PROJECT
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PLAN REFERENCES
■ REFER TO SWM/BMP DETAILS FOR ADDITIONAL SWM/BMP NOTES & DETAILS
• THIS PLAN TO BE UTILIZED FOR SWM/BMP PURPOSES ONLY
Imo, ATM
J1� JZ`1
ENGINEERING NC, PLLC
NCBELS P-1132
1927 S. TRYON STREET, SUITE 310 CHARLOTTE, NC 28203
PHONE: [phone] FAX: [phone]
PROJECT No.: NCC182114 SCALE: 1"=30'
DRAWN BY: RJB CHECKED BY: DR CAD I.D.:HP
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DATE: 11-30-18
REVISION
DATE: 12-5-18
C3.8
H:\2018\NCC182114\DRAWINGS\PLAN SETS\CONSTRUCTION DOCUMENTS\NCC182114HPO.DWG PRINTED BY: DRENCKENS 1.10.19 @ 1:26 PM LAST SAVED BY: DRENCKENS

11/5/2018 Precipitation Frequency Data Server
NOAA Atlas 14, Volume 2, Version 3
Location name: Wingate, North Carolina, USA*�'
Latitude: 34.9821*, Longitude:-80.4566°
Elevation: 563.73 ft**
` ✓ source: ESRI Maps r
** source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok M.Yelda, 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)
Average recurrence interval (years)
Duration
100 1
1 2 5 10 25 50 100 200 500 1000
0.430
0.508
0.589
0.648
0.715
0.762
0.805
0.842
0.886
0.918
5{»in
(0.395-0.467)
(0.466-0.553)
0.812
(0.540-0.641)
0.943
(0.593-0.704)
1.04
(0.652-0.776)
1.14
(0.692-0.826)
1.21
(0.727-0.872)
1.28
(0.757-0.914)
1.34
(0.789-0.964)
1.40
(0.811-1.00)
1.45
0.686
10{»in
(0.631-0.746)
(0.746-0.884)
1.02
(0.865-1.03)
(0.949-1.13)
1 (1.04-1.24)
1 (1.10-1.32)
1 (1.16-1.39) 11
(1.20-1.45)
1 (1.25-1.52)
(1.28-1.58)
0.858
1.19
1.31
1.45
1.54
1.62
1.69
1.77
1.81
15{ttin
(0.789-0.932)
(0.938-1.11)
1 (1.09-1.30)
1 (1.20-1.42)
1 (1.32-1.57)
1 (1.40-1.67)
1 (1.46-1.75) 11
(1.52-1.83)
1 (1.57-1.92)
(1.60-1.98)
1.18
1.41
1.70 1.90
2.14
2.31
2.48
2.62
2.81
2.94
30-min (1.08-1.28)
(1.30-1.54)
(1.55-1.85) (1.74-2.06)
(1.95-2.32)
(2.10-2.51)
(2.24-2.68)
(2.36-2.85)
(2.50-3.05)
(2.60-3.20)
2.85
3.14
3.41
3.68
4.03
4.29
1.47
1.77
2.17 2.47 IF
60{»in
(1.35-1.59)
(1.63-1.93)
(1.99-2.37) (2.26-2.69)
(2.60-3.09)
(2.85-3.40)
(3.08-3.69)
(3.31-3.99)
(3.59-4.38)
(3.79-4.67)
2.05
3.39
3.75
4.12
4.48
4.96
5.32
1.69
2.54 2.91
2-hr
(1.55-1.85)
(1.87-2.24)
(2.32-2.77) (2.65-3.18)
(3.08-3.69)
(3.39-4.09)
(3.70-4.48)
( 4.00-4.88)
( 4.38-5.40)
( 4.66-5.81)
1.80
2.17
2.71 3.13
3.69
4.13
4.57
5.03
5.66
6.16
3-hr
(1 .64-1.98)
(1.99-2.39)
(2.47-2.98) 1 (2.84-3.43)
3.24 3.75 IF
(3.33-4.03)
(3.71-4.51)
(4.09-4.99)
(4.46-5.49)
(4.95-6.18)
(5.34-6.74)
2.15
2.60
4.44
4.99
5.55
6.13
6.93
7.57
6-hr
(1.97-2.36)
(2.38-2.85)
(2.96-3.56) 1 (3.42-4.11)
3.85 4.47
1 (4.01-4.84)
(4.48-5.43)
(4.95-6.04)
(5.42-6.67)
(6.04-7.53)
(6.52-8.23)
2.54
3.07
5.34
6.04
6.76
7.52
8.59
9.45
12-hr
(2.33-2.79)
(2.82-3.38)
(3.52-4.23) 1 (4.08-4.91)
1 (4.83-5.84)
(5.42-6.59)
(6.01-7.36)
(6.61-8.19)
(7.43-9.34)
(8.06-10.3)
3.02
3.64
4.58 5.32
6.37
7.20
8.09
9.01
10.3
11.4
24-hr
(2.78-3.27)
(3.36-3.95)
(4.22-4.96) 1 (4.89-5.77)
1 (5.82-6.90)
(6.57-7.81)
(7.34-8.77)
(8.14-9.79)
1 (9.26-11.2)
(10.1-12.4)
3.55
4.28
5.34 6.19IF
7.36
8.32
9.31
10.4
11.8
13.0
2{lay
(3.28-3.85)
(3.96-4.64)
(4.93-5.79) (5.70-6.70)
5.62 6.49
(6.76-7.98)
(7.61-9.02)
(8.48-10.1)
1 (9.38-11.3)
1 (10.6-12.9)
(11.6-14.2)
3.76
4.52
8.69
9.70
10.8
12.3
13.5
E37.70
�a7yF(3.49-4.07)
(4.19-4.89)
(5.20-6.07) (5.99-7.01)
(7.09-8.33)
(7.97-9.39)
(8.87-10.5) 11
(9.80-11.7)
1 (11.1-13.4)
(12.1-14.7)
4.77
8.04
9.05
10.1
11.2
12.8
14.0
3.98
5.90 6.79­IF
4-day(3.70-4.29)
(4.43-5.14)
(5.47-6.36) (6.28-7.32)
(7.42-8.67)
(8.32-9.77)
(9.26-10.9) 11
(10.2-12.1)
1 (11.6-13.8)
(12.7-15.2)
E7-day
4.59
5.48
6.68 7.64
8.97
10.0
11.2
12.3
14.0
15.3
(4.29-4.91)
(5.13-5.87)
(6.25-7.15) (7.13-8.18)
(8.35-9.61)
(9.31-10.8 )
( 10.3-12.0 )
( 11.3-13.2 )
( 12.8-15.0 )
( 13.9-16.5 )
10-day 5.27
(4.96-5.62)
6.28
(5.89-6.68)
7.56 8.57
(7.08-8.05) (8.02-9.13)
9.95
(9.28-10.6)
11.0
(10.3-11.7)
12.1
(11.3-12.9) 11
13.3
(12.3-14.2)
14.8
1 (13.7-15.9)
16.1
(14.8-17.3)
7.08
8.36
9.88 11.1
12.7
14.0
15.3
16.6
18.4
19.9
20-day
(6.69 7.51)
(7.89-8.86)
(9.31-10.5) (10.4-11.8)
1 (11.9-13.5)
(13.1-14.9)
(14.3-16.3) 11
(15.5-17.7)
1 (17.1-19.7)
(18.4-21.2)
8.69
10.2
11.9 13.2
14.9
16.3
17.6
18.9
20.6
22.0
30-day
(8.24-9.17)
(9.69-10.8)
(11.3-12.6) (12.5-13.9)
1 (14.1-15.7)
(15.3-17.2)
(16.5-18.6) 11
(17.7-20.0)
1 (19.3-21.9)
(20.5-23.4)
10.9
12.8
14.7 16.1
18.0
19.4
20.8
22.2
24.0
25.3
45-day
(10.4-11.5)
1 (12.2-13.5)
1 (14.0-15.4) (15.3-16.9)
1 (17.1-18.9)
(18.4-20.4)
1 (19.7-21.9) 11
(20.9-23.3)
1 (22.5-25.3)
(23.7-26.8)
13.1
15.3
17.3
18.9 IF
20.9
22.4
23.9
25.3
27.1
28.5
60-day
(12.5-13.7)
(14.6-16.0)
(16.5-18.1)
(18.0-19.7)
(19.9-21.8)
(21.3-23.4)
(22.6-25.0)
(24.0-26.5)
(25.6-28.5)
(26.9-30.0)
Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are W 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) w ill be greater than the upper bound (or less than the low er bound) is 5%. Estimates at upper bounds are not
checked against probable maximum precipitation (PIMP) estimates and may be higher than currently valid PMPvalues.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
https:Hhdsc.nws.noaa.g oVhdsc/pfds/pfds_pri ntpag e. html?lat=34.9821 &Ion=-80.4566&data=depth&units=eng I is h&series= pds 1/4

11/5/2018 Precipitation Frequency Data Server
PF graphical
PDS-based depth -duration -frequency {DDF) curves
Latitude: 34.9921 Longitude:-80.4566'
30
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Average recurrence interval (years)
NOAA Atlas 14, Volume 2, Version 3 Created (GMT}: Mon Nov 5 14:49-24 241a
Back to Top
Maps & aerials
Small scale terrain
Average recurrence
rnteival
(years)
— 1
— 10
25
50
100
200
500
1D00
Duration
— 5-min
— 2-day
— I "in
— 3-day
15-min
— 4-day
— 30-min
— 7-day
— 60-min
— 10-day
— 2-hr
— 20-day
— 3-hr
— 30-day
— "r
— 46-day
— 12,hr
— 6 -day
— 24-hr
https:Hhdsc.n\As.noaa.gov/hdsc/pfds/pfds printpag e. html?I at=34.9821 &Ion=-80.4566&data=depth&units=eng I is h&series= pds
2/4

11/5/2018 Precipitation Frequency Data Ser\er
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https://hdsc.nm.noaa.g oVhdsc/pfds/pfds_pri ntpag e. html A at= 34.9821 &Ion= -80.4566&data= dept h&u nits= eng I is h&seri es= pds 3/4

11 /5/2018
Precipitation Frequency Data Server
Back to Top
US Department of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
National Water Center
1325 East West Highway
Silver Spring, MD 20910
Questions?: [e-mail]
Disclaimer
https://hdsc.nm.noaa.g oVhdsc/pfds/pfds_pri ntpag e. htmI A at= 34.9821 &Ion= -80.4566&data= dept h&u nits= eng I is h&seri es= pds 4/4

11/5/2018 Precipitation Frequency Data Server
NOAA Atlas 14, Volume 2, Version 3
Location name: Wingate, North Carolina, USA*�'
Latitude: 34.9821*, Longitude:-80.4566°
Elevation: 563.73 ft**
` ✓ source: ESRI Maps r
** source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
G.M. Bonnin, D. Martin, B. Lin, T. Parzybok M.Yelda, 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)
luration 0000000000
1 2 5 10 25 50 100 200 500 1000
5-min 5.16 6.10 7.07 7.78 8.58 9.14 9.66 10.1 10.6 11.0
(4.74-5.60) (5.59-6.64) (6.48-7.69) 1 (7.12-8.45) 11 (7.82-9.31) 1 (8.30-9.91) (8.72-10.5) (9.08-11.0) (9.47-11.6) (9.73-12.0)
10{nin 4.12 4.87 5.66 6.22 6.84 7.28 7.67 8.01 8.41 8.67
(3.79-4.48) (4.48-5.30) (5.19-6.16) (5.69-6.75) (6.23-7.42) 1 (6.61-7.89) (6.93-8.31) (7.20-8.69) (7.49-9.14) (7.66-9.45)
15�nin 3.43 4.08 4.77 5.24 5.78 6.14 6.46 6.74 7.06 7.26
(3.16-3.73) (3.75-4.45) (4.38-5.20) (4.80 5.70) (5.27-6.27) (5.58-6.66) (5.84-7.00) (6.06-7.32) (6.28-7.67) (6.41-7.91)
30�nin 2.35 2.82 3.39 3.80 4.28 4.63 4.95 5.25 5.62 5.88
(2.16-2.56) (2.59-3.07) (3.11-3.69) (3.48-4.13) 1 (3.90-4.64) (4.20-5.02) (4.47-5.36) (4.72-5.69) (5.00-6.11) 1 (5.19-6.40)
60�nin 1.47 1.77 2.17 T 2.47 2.85 3.14 3.41 3.68 4.03 4.29
(1.35-1.59) 1 (1.63-1.93) (1.99-2.37) (2.26-2.69) (2.60-3.09) 1 (2.85-3.40) 1 (3.08-3.69) (3.31-3.99) 1 (3.59-4.38) 1 (3.79-4.67)
2-hr 0.845 1.02 1.27 1.45 F 1.70 1.88 2.06 2.24 2.48 2.66
(0.775-0.924) (0.937-1.12) (1.16-1.39) (1.33-1.59) (1.54-1.85) 1 (1.70-2.04) 1 (1.85-2.24) (2.00-2.44) 1 (2.19-2.70) (2.33-2.90)
3-hr 0.598 0.723 T 0.902 T 1.04 1.23 T 1.38 1.52 1.68 1.89 2.05
(0.547-0.658) (0.661-0.796) (0.824-0.991) (0.947-1.14) 1 (1.11-1.34) 1 (1.24-1.50) 1 (1.36-1.66) 1 (1.49-1.83) 1 (1.65-2.06) (1.78-2.24)
6-hr 0.359 0.433 0.541 0.626 0.741 0.832 0.926 1.02 1.16 1.26
(0.328-0.394) (0.397-0.476) (0.495-0.594) (0.570-0.686) (0.671-0.809) (0.748-0.907) (0.827-1.01) (0.904-1.11) 1 (1.01-1.26) 1 (1.09-1.37)
12-hr 0.211 0.255 0.320 0.371 0.443 0.501 0.561 0.624 0.713 0.784
(0.193-0.231) (0.234-0.281) (0.292-0.351) (0.338-0.407) (0.401-0.484) (0.450-0.547) (0.499-0.611) (0.549-0.680) (0.616-0.775) (0.669-0.854)
0.126
0.152 0.191 0.222 0.265 0.300 0.337 0.375
0.430
0.474
24-hr
(0.116-0.136)
0.074
(0.140-0.164) (0.176-0.207) (0.204-0.240) (0.243-0.287) (0.274-0.325) (0.306-0.366) (0.339-0.408)
0.089 0.111 0.129 0.153 0.173 0.194 0.216
(0.386-0.467)
0.246
(0.423-0.516)
0.271
2{lay
(0.068-0.080)
0.052
(0.082-0.097) (0.103-0.121) (0.119-0.140) (0.141-0.166) (0.158-0.188) (0.177-0.211) (0.195-0.235)
0.063 0.078 0.090 0.107 0.121 0.135 6.150
(0.221-0.269)
0.171
(0.242-0.296)
0.188
3tlay
(0.048-0.056)
(0.058-0.068) (0.072-0.084) (0.083-0.097) (0.098-0.116) (0.111-0.130) (0.123-0.146) (0.136-0.162)
.1
50
(0.154-0.186)
(0.169-0.205)
6
4{lay
(0.038-0.045)
(0.046-0 054) (0.057--0 066) (0.8 076) (0.077--0 090) (0. 87--0.102) (0. 96 0514) (0.106-0.126)
(0.121-0.3144)
(0.132-0.159)
0.027
0.033 0.040 0.045 0.053 0.060 0.066 0.073
0.083
0.091
play
(0.026-0.029)
0.022
(0.031-0.035) (0.037-0.043) (0.042-0.049) (0.050-0.057) (0.055-0.064) (0.061-0.071) (0.067-0.079)
0.026 0.032 0.036 0.041 0.046 0.051 0.055
(0.076-0.089)
0.062
(0.083-0.098)
0.067
10tlay
(0.021-0.023)
0.015 IF
(0.025-0.028) (0.030-0.034) (0.033-0.038) (0.039-0.044) (0.043-0.049) (0.047-0.054) (0.051-0.059)
0.017 0.021 0.023 T 0.026 0.029 0.032 0.035
(0.057-0.066)
0.038
(0.062-0.072)
0.041
20tlay
(0.014 0.016)
0.012
(0.016-0.018) (0.019-0.022) (0.022-0.024) (0.025-0.028) (0.027-0.031) (0.030-0.034) (0.032-0.037)
0.014 0.017 0.018 0.021 0.023 0.024 0.026
(0.036-0.041)
0.029
(0.038-0.044)
0.031
30tlay
(0.011-0.013)
0.010
(0.013-0.015) (0.016-0.017) (0.017-0.019) (0.020-0.022) (0.021-0.024) (0.023-0.026) (0.025-0.028)
0.012 0.014 0.015 0.017 0.018 0.019 0.021
(0.027-0.030)
0.022
(0.028-0.032)
0.023
45tlay
(0.010-0.011)
--
(0.011-0.012) (0.013-0.014) (0.014-0.016) (0.016-0.017) (0.017-0.019) (0.018-0.020) (0.019-0.022)
0.011 0.012 0.013 0.015 0.016 0.017 0.018
(0.021-0.023)
0.019
(0.022-0.025)
0.020
[��]FO.009
(0.009 0.010)
(0.010 0.011) (0.011 0.013) (0.012 0.014) (0.014-0.015) (0.015-0.016) (0.016-0.017) (0.017-0.018)
(0.018-0.020)
(0.019-0.021)
Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
ars in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a
duration and average recurrence interval) w ill be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not
ed against probable maximum precipitation (PIMP) estimates and may be higher than currently valid PMP values.
refer to NOAA Atlas 14 document for more information.
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11/5/2018 Precipitation Frequency Data Server
PF graphical
PD5-based intensity -duration -frequency (IDF) curves
Latitude: 34.9821 Longitude:-80.4566'
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1. 2 5 10 25 50 104 200 500 1040
Average recurrence interval (years)
NOAA Atlas 14, Volume 2, Version 3 Created (GMT}: Mon Nov 5 14:50:15 2019
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Maps & aerials
Small scale terrain
Average recurrence
rntenral
{years)
— 1
2
— 6
— 10
25
50
100
200
— 500
1000
Duration
— 5-min
— 2-day
— I "in
— 3-day
15-min
— 4-day
— 30-min
— 7-day
— 60-min
— 1O-day
— 2-hr
— 20-day
— 3-hr
— 30-day
— "r
— 46-day
— 12,hr
— 6 -day
— 24-hr
https:Hhdsc.n\As.noaa.gov/hdsc/pfds/pfds printpag e. html?I at=34.9821 &Ion=-80.4566&data=intensity&units= eng I is h&series=pds
2/4

11/5/2018 Precipitation Frequency Data Ser\er
f4
Win+te
L�
Urn
Large scale terrain
City �
kh Winston-Salem
• • Durham
Greensboro •
Ralei
9
*psherille NORTH CAROL INA
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Greenville ev
SOUTH CAROLINA +
ilmi
100km 7bia
60m i
Large scale map
Winston Salem Greensboro
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arn
Ra lelg
.,Asheville North +
Carolina
Nolte
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—
100km
oli
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https://hdsc.nm.noaa.g oVhdsc/pfds/pfds_printpage. html A at= 34.9821 &Ion= -80.4566&data= i ntensity&un its= eng I is h&s eri es= pds 3/4

11 /5/2018
Precipitation Frequency Data Server
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US Department of Commerce
National Oceanic and Atmospheric Administration
National Weather Service
National Water Center
1325 East West Highway
Silver Spring, MD 20910
Questions?: [e-mail]
Disclaimer
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Appendix