SW6200903_2020.10.16 SIA Report_20201022

5614/9#6'4/#0#)'/'064'2146
for
9+0%*'56'4
57$&+8+5+10
Submittal to:
Hoke County
NCDOT
NCDEMLR STORMWATER
Prepared for:
STAFFORD TURNER DEVELOPMENT, LLC.
246 VALLEYFIELD LANE
SOUTHERN PINES, NC 28387
CONTACT: BOB STAFFORD
PHONE: [phone]
Submittal Date:
SEPTEMBER 14, 2020
Resubmittal Date:
October 21, 2020
Prepared by:
,6JQOCU'PIKPGGTKPI+PE
EKXKNGPIKPGGTKPI RNCPPKPI
143CharlotteAvenue,Suite104
Sanford,NorthCarolina27330
919Ͳ777Ͳ6010phone
www.jthomasengineering.com
LicenseNo.CͲ3389
JTE Project #: 20-
DDS Project# 2019- 23
TABLE OF
CONTENTS
SECTION PAGE
I. EXISTING CONDITIONS
A. PROPERTY ..............................................................................………………….1
B. WATERSHED ...........................................................................………………….2
C. JURISDICTIONAL WATERS......................................................………………….2
D. FEMA FLOOPLAIN… ..............................................................………………….2
E. SOILS…...................................................................................………………….2
II.AGENCY STORMWATER REQUIREMENTS
A. Hoke County …………..........................................................……………….….2
B.NCDEQ ..................................................................................…………………..3
III.PROPOSED IMPROVEMENTS
A. PROJECT DESCRIPTION.........................................................…………………..3
B.LAND DISTURBANCE AND EROSION CONTROL…........……………………….3
C. IMPERVIOUS SURFACE ..................................................………………………..3
D. DRAINAGE AND STORMWATER MANAGEMENT… ..............………………….4
APPENDICES
A.
B.
C.
D.
E.
F.
Computations
Minor System
Grass Conveyance Swales
Erosion Control
Maps
Inlet Drainage Area
Erosion Control Drainage Area
Soil Survey Map
FEMA FIRM Map
USGS MAP
SUPPLEMENT-EZ
OPERATION & MAINTENANCE AGREEMENT
BMP SUPPLEMENT FORMS
I. EXISTING CONDITIONS
A. PROPERTY
The proposed project site is on one 30.71 AC parcel(PIN# 4948-40-30-
1004) in Hoke County. The property is currently undeveloped farm land
with no impervious surfaces.
The following is a summary of the adjacent properties:
To the north, undeveloped (zoning R-20)
To the south, undeveloped (zoning R-20)
To the west, undeveloped (zoning R-20)
To the east, single family and undeveloped (zoning R-20)
See Figure 1 below for an aerial view of the property for the proposed
Winchester Subdivision project (Site).
Figure 1: Aerial view of pre-developed site
Site
Stormwater Impact Analysis – Winchester Subdivision
Page 1 | 4
SITE

B. WATERSHED

The site is located in the Gully Branch Watershed and Cape Fear River
Basin. The NCDEQ Stream Index for Gully Branch is 18-31-20.7 and
Stream Classification for Gully Branch is ‘B’.

C. JURISDICTIONAL WATERS

There are no jurisdictional streams located on the site. There are no
impacts proposed with this project to jurisdictional streams or
wetlands.

D. FEMA FLOODPLAIN

There are no FEMA mapped floodplains located on the site per FIRM
Panel 3710948400K, effective date Jan. 5, 2007. See Appendix D for
FEMA FIRM maps.

E. SOILS

Refer to Appendix C for the NRCS map showing anticipated on-site soils.

II. AGENCY STORMWATER REQUIREMENTS

A. Hoke County

Section 3.7 ‘Storm Drainage Not in Public Streets” of the Hoke County
Subdivision Ordinance details the requirements for managing
stormwater from new construction sites.

Section 3.3 ‘Streets” of the Hoke County Subdivision Ordinance details
the requirements for managing stormwater from new construction sites
per NCDOT requirements.

Stormwater Impact Analysis – Winchester Subdivision
Page 2 | 4

B. NCDEQ

Hoke County is a ‘tipped’ county and new projects located within the
county must meet NCDEQ Post Construction Stormwater Phase 2
regulations. Site requirements for stormwater control are different if the
proposed development is ‘high density’ (greater than 24% impervious) or
‘low density’ (less than 24% impervious).

III. PROPOSED IMPROVEMENTS

A. PROJECT DESCRIPTION

The proposed project will create thirty-three (33) single family lots (min
20,000 sf). The proposed project will add additional roads the Hoke County
road system. The design follows the Preliminary Plat that was recently
approved by Hoke County. As part of this project, public water will be
extended to serve the new lots.

B. LAND DISTURBANCE AND EROSION CONTROL

The proposed disturbed area for the proposed project is 29.1 AC +/-. A
NCDEQ Land Disturbance (Erosion Control) Permit will be obtained prior to
beginning work.

C. IMPERVIOUS SURFACE

The proposed total amount of impervious surfaces for this project is 4.66 AC.
This includes pavement and curb & gutters in the public R/W and driveways
and rooftops on each lot. The resulting percent impervious (or built-upon)
of 15.2% of the total property area. A maximum amount of 3,500 SF of
impervious area is allocated to each lot. Thus, this development is classified
as ‘low density’ under NCDEQ Phase II regulations.

Stormwater Impact Analysis – Winchester Subdivision
Page 3 | 4
D. DRAINAGE AND STORMWATER MANAGEMENT
i.Roadway Drainage – Minor System
The proposed roadway will have curb and gutter. Catch basins in
the gutter line will provide the roadway drainage. Catch basins
were spaced based on gutter spread not exceeding one-half lane
width during a 4 in/hr storm (NCDOT guidelines). The minor pipe
system is sized based on 10-year storm flow and cross-pipes are
sized based on 25-year storm flow not exceeding the hydraulic
capacity of each pipe segment (as open channel flow, that is, non-
pressure flow).
ii.Grass Conveyance Swales
As stated in Section III. C. above, proposed impervious is less than 24%
and, therefore is classified as ‘Low Density’ per NCDEQ regulations.
Per NCDEQ guidance, Grass swales are proposed to receive runoff
collected by the catch basins in the road system to help treat the
runoff before being discharged to the jurisdictional waters. These
swales have a longitudinal slope of 0.1% to 0.5% that discharge into
an existing drainage swale to the south. There are four (4) proposed
grass swales, each with a length greater than 100 LF.
iii.Methodology and computations
Refer to Appendix A for storm drainage and stormwater
management computations. Hydrologic computations were based
on the Rational Method for storm drainage and SCS method for
stormwater management. Rainfall intensity was determined based
on data of the closest rainfall gauge listed on the NOAA website.
Drainage areas were delineated based on a combination of field
and LIDAR topography.
Stormwater Impact Analysis – Winchester Subdivision
Page 4 | 4
APPENDIX A
WINCHESTER SUBDIVISIONDRAINAGE/GUTTER SPEAD CALCULATIONSInlet ID Inlet IDUpstream Inlet Runoff Coeficient Drainage Area (acres)Inlet Rainfall Intensity* (in/h)Pipe Diameter (in)Pipe Material Pipe Length (ft)Pipe Capacity (Full Flow) (ft³/s)Total Pipe Flow (ft³/s) (1)Total System Flow (ft³/s)Pipe Slope (ft/ft) Pipe Invert (Upstream) (ft) Pipe Invert (Downstream) (ft)Inlet IDElevation (Top) (ft) (3)Inlet Elevation (Invert) (ft)Inlet TypeGutter I=4 in/hr (ft³/s) (2)Gutter Flow (Total Intercepted) (ft³/s)Gutter Flow (Total Bypassed) (ft³/s)Gutter Spread (ft) (4)NotesFES 405 (5) CB 402 0.3017.925.9930 Class III RCP 60.0044.4032.2032.20 0.0107198.84198.20FES 405 (5) 200.00 198.84----DI 407 (6) CB 403 0.330.765.6115 Class III RCP 28.004.941.411.410.0054197.55197.40DI 407 (6) 200.55 197.55NCDOT 840.22-DI 406 CB 404 0.330.435.6115 Class III RCP 22.004.940.800.800.0068197.55197.40DI 406 200.55 197.69NCDOT 840.22CB 404 CB 403 0.350.485.6115 Class III RCP 28.004.940.941.740.0054197.55197.40CB 404 201.55 197.55NCDOT 840.03 (DOUBLE) 0.671.66-3.50 SAG - 0.5" GRATE DEPRESSIONCB 403 CB 401 0.350.765.5018 Class III RCP 90.9010.731.464.610.0088197.40196.60CB 403 201.55 197.40NCDOT 840.03 (DOUBLE) 1.061.46-3.50 SAG - 0.5" GRATE DEPRESSIONCB 402 CB 401 0.700.007.9730 Class III RCP167.00 43.530.0032.20 0.0096198.20196.60CB 402 203.59 198.20NCDOT 840.03----CB 401 JB 401A 0.350.107.9730 Class III RCP 12.0035.540.2837.09 0.0075196.60196.51CB 401 202.63 196.60NCDOT 840.030.140.300.043.00JB 401A FES 400---30 Class III RCP302.00 35.540.0069.29 0.0070196.51194.39JB 401A 202.63 196.51NCDOT 840.03#VALUE! 0.300.043.00CB 301 JB 301A 0.351.497.9718 Class III RCP 12.006.334.164.160.0050196.00195.94CB 301 199.00 196.00NCDOT 840.032.092.68-4.92 SAG - 0.5" GRATE DEPRESSIONJB 301A FES 300---18 Class III RCP148.006.330.004.160.0050195.94195.20JB 301A 199.00 195.94NCDOT 840.03#VALUE! 2.68-4.92 SAG - 0.5" GRATE DEPRESSIONCB 208 CB 203 0.330.907.9724 Class IV RCP 96.0021.912.3718.31 0.0080195.87195.10CB 208 199.67 195.87NCDOT 840.031.191.050.156.00FES 207 (5) CB 208 0.309.265.7424 Class III RCP122.00 17.3215.9515.95 0.0050197.00196.39FES 207 (5) -197.00NCDOT 840.22----CB 206 CB 205 0.350.425.6215 Class III RCP 28.004.950.830.830.0050196.39196.25CB 206 199.51 196.39NCDOT 840.030.591.010.155.70CB 205 DI 2040.350.655.6215 Class III RCP 48.004.951.282.100.0052196.25196.00CB 205 199.51 196.25NCDOT 840.030.911.350.265.83 1.0" GRATE DEPRESSIONDI 204 CB 203A 0.350.407.9715 Class III RCP 20.004.941.123.220.0500196.07195.07DI 204 199.00 196.07NCDOT 840.22----CB 203A CB 203 0.350.697.9715 Class IV RCP 15.005.721.925.150.0067195.07194.97CB 203A 198.90 195.07NCDOT 840.031.011.01-2.50SAGCB 203 CB 201 0.350.107.9724 Class IV RCP 28.0020.640.2823.74 0.0071194.97194.77CB 203 199.00 194.97NCDOT 840.030.700.660.045.95CB 202 CB 201 0.350.817.9715 Class IV RCP 18.004.942.262.260.0067194.89194.77CB 202 198.90 194.89NCDOT 840.031.271.60-3.50SAGCB 201 JB 201A 0.350.637.9730 Class III RCP 12.0031.411.7625.49 0.0050194.77194.71CB 201 199.00 194.77NCDOT 840.030.880.990.145.80JB 201A FES 200---30 Class III RCP208.00 31.410.0025.49 0.0050194.71193.67JB 201A 199.00 194.71NCDOT 840.03#VALUE! 0.990.145.80FES 101 (5) FES 100 0.3010.485.8624 Class IV RCP 72.0020.3518.4218.42 0.0069197.50197.00FES 101 (5) -197.50NCDOT 840.03-FLUME 1 OUTLET 0.850.087.97- Concrete Flume 10.0017.320.540.540.0150200.45200.30FLUME 1-200.45Concrete Flume0.270.54-1.40SAGFLUME 1 OUTLET 0.850.087.97- Concrete Flume 10.0017.320.540.540.0150200.45200.30FLUME 1-200.45Concrete Flume0.270.54-1.40SAGNotes 1 Storm System Sizing based on 10-yr Storm2 Gutter Spread Calculations based on Storm Intensity of 4 in/hr3 CB (Catch Basin) Top Elevation is Grate at EOP4 Gutter Spread Width is measured from Edge of Pavement5 Cross Pipe Sizing based on 25-yr Storm6 Inlet area calculated if alternate grading pattern on lots
STRUCTURES 200-202
STRUCTURES 200-206
STRUCTURES 200-207
STRUCTURES 301-300FES300
STRUCTURES 405-400
STRUCTURES 406-400
STRUCTURES 407-400
Outlet Protection #100
New York Method 8.06.5 Manual 
Q= 15.56 cfs La= 8 FT
24 in W= 6 FT
5.83 ft/s d= 12 IN
1 Class A
Outlet Protection #200
New York Method 8.06.5 Manual 
Q= 36.01 cfs La= 18 FT
36 ft W= 9 FT
5.31 ft/s d= 18 IN
2 Class B
Outlet Protection #300
New York Method 8.06.5 Manual 
Q= 5.34 cfs La= 6 FT
18 in W= 4.5 FT
3.52 ft/s d= 12 IN
1 Class A
Outlet Protection #400
New York Method 8.06.5 Manual 
Q= 32.94 cfs La= 15 FT
30 in W= 7.5 FT
6.71 ft/s d= 18 IN
2 Class B
Pipe Diameter
Velocity=
Zone= Stone Diameter=
Pipe Diameter
Velocity=
Zone= Stone Diameter=
Pipe Diameter
Velocity=
Pipe Diameter
Velocity=
Zone= Stone Diameter=
Zone= Stone Diameter=
U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only) Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.27= 16.2 mins
Winchester Subdivison
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA #101
1
FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
1,410
0.050
3.8
0.10 0.10
6.0
9.0
0.7
0.005
0.03
2.7
209
0.02 0.02
0.27
06/04

U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only) Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.29= 17.4 mins
Winchester Subdivision
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA #207
1
WOODS,FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
1,142
0.050
3.8
0.08 0.08
3.0
12.0
0.3
0.005
0.03
1.4
295
0.06 0.06
0.29
06/04

U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only)Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.25= 15.0 mins
Winchester Subdivision
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA #405
1
FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
1,137
0.050
3.8
0.08 0.08
1
8.5
12.1
0.7
0.005
0.02
3.8
321
0.02 0.02
0.25
06/04


Permanent Channel #1 => DA #PD 1
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.33
I=5.86 in/hr CALC Tc
Q25 + FES 100+= 39.07 A=11.60 ac
FLUME 1 &2
Channel Slope=0.50 Includes PC #2
Channel Depth=2.00
Channel Bottom Width=2.00
Side Slopes=4.00
Velocity=3.60
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=1.34 ft
T=0.41808 lbs/ft2 s=0.005 ft/ft
Temporary=NAG S75BN
Permanent=Fescue
Permanent Channel #2 => DA #PD 2
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.30
I=5.86 in/hr CALC Tc
Q25 = 18.42 A=10.48 ac
Channel Slope=0.50
Channel Depth=1.00
Channel Bottom Width=2.00
Side Slopes=3.00
Velocity=3.32
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=0.97 ft
T=0.30264 lbs/ft2 s=0.005 ft/ft
Temporary=NAG S75BN
Permanent=Fescue
Permanent Channel #3 => DA #PD 3
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.33
I=8.90 in/hr
Q25 + FES 200= 51.57 A=5.22 ac
Channel Slope=0.10
Channel Depth=2.00
Channel Bottom Width=6.00
Side Slopes=4.00
Velocity=2.29
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=1.74 ft
T=0.108576 lbs/ft2 s=0.001 ft/ft
Temporary=NAG S75BN
Permanent=Fescue
Permanent Channel #4 => DA #PD 4
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.33
I=8.90 in/hr
Q25 + FES 300= 8.07 A=0.93 ac
Channel Slope=0.10
Channel Depth=3.00
Channel Bottom Width=6.00
Side Slopes=4.00
Velocity=1.36
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=0.68 ft
T=0.42432 lbs/ft2 s=0.01 ft/ft
Temporary=NAG S75BN
Permanent=Fescue
Permanent Channel #5 => DA #PD 5
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.33
I=8.89 in/hr
Q25 + FES 200= 57.39 A=8.27 ac
Channel Slope=0.60
Channel Depth=3.00
Channel Bottom Width=3.00
Side Slopes=4.00
Velocity=4.33
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=1.82 ft
T=0.681408 lbs/ft2 s=0.006 ft/ft
Temporary=NAG S75BN
Permanent=Fescue
Permanent Channel #6 => DA #PD 6
Calculate Flow - Rational Method
25-Yr Storm
Q25 = CIA C=0.33
I=4.78 in/hr CALC TC
Q25 = 33.61 A=17.92 ac
Channel Slope=0.50
Channel Depth=1.50
Channel Bottom Width=2.00
Side Slopes=4.00
Velocity=3.92
Soil Type @ sandy loam Slopes=0-10%
Channel Lining
Shear Calculation
T=yds y=62.4 lbs
dwater=1.22 ft
T=0.38064 lbs/ft2 s=0.005 ft/ft
Temporary=NAG S75BN
Permanent=Fescue

Sediment Basin # 1
Calculate Flow ‐ Rational Method
10‐Yr Storm 25‐Yr Storm 
Q10 = CIA C= 0.30
Q25 = CIA C= 0.30
I*= 5.20 I*= 5.80
Q10 = 39.78 A= 25.50
Q25 = 44.37 A= 25.50
2‐Yr Storm 
Q2 = CIA C= 0.30
I*= 3.98 *Intensity per Tc
Q2 = 30.45 A= 25.50
Calculate Required Surface Area
SA=Q10 x 325 sf/cfs Q10 = 39.78
SA= 12928.50 ft2
Side Slopes = 3.00 :1
Pond Depth= 4.00 ft
Basin Dims  (Per SA)
Top = 70.00 x 210.00 = 14700 ft2
Bottom = 46 x 186 = 8556 ft2
Volume Required 
VR=Ax1800 cf/ac A= 25.50 ac
VR=45900.00 ft3
Volume Proposed 
VP=((Top Area + Bottom Area)/2)xD Top= 14700.00 sf
Bottom= 8556.00 sf
VP=46512.00 ft3 D= 4.00 ft
Skimmer Sizing 
Calculate Dewater Time 
Qd=V/Td V= 46512.00
ft3
Td= 5 3‐5 days typ
Qd=9302.40 cfs
Calculate Orifice Diameter
D=sqrt((Qd/(2310sqrt(h))) Qd= 9302.40
h= 0.33
D= 2.65
Use 6 2.65 " Orifice
Principle Spillway Sizing 
L=Q2/(cH1.5)L= ? ft
H= 1.50 ft
c= 3.10
L= 5.35 ft
Riser Sizing 
C=pi X D C= 5.35 ft
pi= 3.14
D= 20.43 in D= ? ft
Material= CMP
Use  24.00 "CMP Riser
Barrel Sizing 
Q2= CA X sqrt(2gh)C= 0.60
A= ? sf
A= 2.70 Q2= 30.45 cfs
h= 5.50 ft
A=pi X r2 g= 32.20 ft/s
A= 22.24 in 
Material= CMP
Use  18.00 "CMP Barrel
Size Riser/Barrel Base 
Calculate Bouyance Force on Riser 
Cross‐sectional area
 " Skimmer w/
A=(pi x r2) x 2 r= 0.85
A= 4.55 sf
Riser Volume 
V=A x L A= 4.55
L= 4.00
V= 18.21
Bouyance Force
FB=qV q= 62.40 lbs
V= 18.21 ft3
FB= 1136.00 lbs/cf
Concrete Base Sizing
(Concrete = 120 lbs/cf) ‐ (weight of water = 62.4 lbs/cf) == 57.6 lbs/cf
Base Volume 19.72 cf
Base Dims = 4.44 ft    x 4.44 ft     x 1.00 ft
Weir Sizing 
Per AutoCad Hydraflow Software 
L= 35.00 ft
D= 1.80 ft
dwater=0.50 ft
Q25= 44.37 cfs
Velocity= 2.31 ft/s
Weir Lining 
Shear Calculation 
T=yds y= 62.4 lbs
dwater=0.5 ft
T= 0.312 lbs/ft2 s= 0.01 ft/ft
Required Liner= Class A Rip Rap
Proposed Liner= Class A Rip Rap
Barrel Outlet Protection 
New York Method 8.06.5 Manual 
18.00 " 9 ft
9.6 ft/s 4.5 ft
2 Class B
Stone d= 18 in
Diameter of Barrel =
Velocity=
Zone= Stone Diameter=
W=
La=
Skimmer Basin # 2
Calculate Flow ‐ Rational Method
10‐Yr Storm 25‐Yr Storm 
Q10 = CIA C= 0.5
Q25 = CIA C= 0.5
I= 7.98 I= 8.89
Q10 = 21.945 A= 5.5
Q25 = 24.4475 A= 5.5
Calculate Required Surface Area
SA=Q10 x 325 sf/cfs Q10 = 24.4475 cfs
SA= 7945.438
Side Slopes = 3:1
Pond Depth= 3ft
Basin Dims 
Top = 64 x 128 = 8192 sf
Bottom = 46 x 110 = 5060 sf
Volume Required 
VR=Ax1800 cf/ac A= 5.5
VR=9900
Volume Proposed 
VP=((Top Area + Bottom Area)/2)xD Top= 8192
Bottom= 5060
VP=19878 D= 3
OK
Weir Sizing 
Per AutoCad Hydraflow Software 
L= 15 ft
D= 2 ft
dwater=0.64 ft
Q25= 24.4475 cfs
Velocity= 2.45 ft/s
Weir Lining 
Shear Calculation 
T=yds y= 62.4 lbs
dwater=0.64 ft
T= 0.39936 lbs/ft2 s= 0.01 ft/ft
Use Class A Rip Rap
Skimmer Sizing 
Calculate Dewater Time 
Qd=V/Td V= 9900
Td= 3 2‐5 days typ
Qd= 3300
Calculate Orifice Diameter
D=sqrt((Qd/(2310sqrt(h))) Qd= 3300
h= 1.75
D= 1.374708
Use 4  " Skimmer w 1.4 Orifice
Skimmer Outlet Protection #7
New York Method 8.06.5 Manual 
4.00 " 1.32 Use 7.5 ft
2.36 ft/s 1 Use 3.0 ft
1 Class A
Diameter of Barrel = La=
Velocity= W=
Zone= Stone Diameter=
Temporary Diversion/Berm #1  => DA #TD1
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I*= 5.37 in/hr
Q25 = 48.76 A= 22.70 ac
Channel Slope=0.50
Channel Depth=2.50 *Intensity per Tc
Side Slopes=3.00
Velocity=4.42
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=1.9 ft
T= 0.5928 lbs/ft2 s= 0.005 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
Temporary Diversion/Berm #2  => DA #TD2
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I= 8.89 in/hr
Q25 = 4.27 A= 1.20 ac
Channel Slope=0.50
Channel Depth=1.50
Side Slopes=3.00
Velocity=2.42
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=0.75 ft
T= 0.234 lbs/ft2 s= 0.005 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
Temporary Diversion/Berm #3  => DA #TD3
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I= 8.89 in/hr
Q25 = 7.47 A= 2.10 ac
Channel Slope=0.60
Channel Depth=1.50
Side Slopes=3.00
Velocity=2.78
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=0.93 ft
T= 0.29016 lbs/ft2 s= 0.005 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
Temporary Diversion/Berm #4  => DA #TD4
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I= 8.89 in/hr
Q25 = 8.89 A= 2.50 ac
Channel Slope=0.60
Channel Depth=1.50
Side Slopes=3.00
Velocity=3.11
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=0.96 ft
T= 0.359424 lbs/ft2 s= 0.006 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
Temporary Diversion/Berm #5  => DA #TD5 (CLEANWATER)
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I= 6.05 in/hr
Q25 = 56.31 A= 23.27 ac
Channel Slope=0.50 *Intensity per Tc
Channel Depth=2.50
Side Slopes=3.00
Velocity=4.49
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=2ft
T= 0.624 lbs/ft2 s= 0.005 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
Temporary Diversion/Berm #6  => DA #TD6 (CLEANWATER)
Calculate Flow ‐ Rational Method
25‐Yr Storm 
Q25 = CIA C= 0.40
I= 6.51 in/hr
Q25 = 20.57 A= 7.90 ac
Channel Slope=0.50 *Intensity per Tc
Channel Depth=2.00
Side Slopes=3.00
Velocity=3.57
Soil Type @ clay Slopes=0‐10%
Channel Lining
Shear Calculation 
T=yds y= 62.4 lbs
dwater=1.37 ft
T= 0.42744 lbs/ft2 s= 0.005 ft/ft
Temporary= NAG S75BN
Permanent= NAG S75BN
U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only) Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.28= 16.8 mins
Winchester Subdivision
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA SB #1
1
FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
1,868
0.050
3.8
0.14 0.14
2.7
0.28
06/04

U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only) Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.24= 14.4 mins
Winchester Subdivision
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA TD #5
1
FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
1,335
0.050
3.8
0.10 0.10
2.7
0.24
06/04

U.S. Department of Agriculture FL-ENG-21B
Natural Resources Conservation Service 04/04
TR 55 Worksheet 3: Time of Concentration (Tc) or Travel Time (Tt)
Project: Designed By: Date:
Location: Checked By: Date:
Circle one: Present Developed
Circle one: Tc Tt through subarea
NOTES: Space for as many as two segments per flow type can be used for each worksheet. Include a map, schematic,
or description of flow segments.
Sheet Flow (Applicable to Tc only) Segment ID
1. Surface description (Table 3-1) ................................................
2. Manning’s roughness coeff., n (Table 3-1) ..............................
3. Flow length, L (total L < 100 ft) .............................................. ft
4. Two-year 24-hour rainfall, P2.................................................. in
5. Land slope, s ....................................................................... ft/ft
6. Tt = 0.007 (nL) 0.8 Compute Tt .......................... hr + =
P2
0.5 s0.4
Shallow Concetrated Flow Segment ID
7. Surface description (paved or unpaved) ...................................
8. Flow length, L ......................................................................... ft
9. Watercourse slope, s ........................................................... ft/ft
10. Average velocity, V (Figure 3-1) .......................................... ft/s
11. Tt = L Compute Tt ......................... hr + =
3600 V
Channel Flow Segment ID
12. Cross sectional flow area, a ............................................... ft2
13. Wetted perimeter, Pw ......................................................... ft
14. Hydraulic radius, r = a Compute r .................................. ft
Pw
15. Channel Slope, s ............................................................ ft/ft
16. Manning’s Roughness Coeff., n ............................................
17. V = 1.49 r
2/3 s1/2 Compute V ...................... ft/s
n
18. Flow length, L ...................................................................... ft
19. Tt = L Compute Tt .................................... hr + =
3600 V
20. Watershed or subarea Tc or Tt (add Tt in steps 6, 11, and 19 ................................................................. hr
0.21= 12.6 mins
Winchester Subdivision
MTB
Hoke County, NC JRT
Check ✔
Check ✔DA TD#6
1
FIELDS
0.03
100
0.1
0.050
0.14 0.14
2
UNPAVED
879
0.050
3.8
0.06 0.06
2.7
0.21
06/04


APPENDIX B

INV.=
1
9
6
.
3'INV.=1
9
5
.
5
9'CTCT
TGRAYSTONE LANEHAYL
O
F
T

C
O
U
R
T
CRAFTSMAN COURT
NEWCASTLE COURTX 199.7X 199.7X 201
.0X 199.4X 199.6 X 201.0X 200.5X
2
0
0
.
1
0
E
P X 19
9
.85EPX
2
0
0
.
2
8
E
P X 199.66EPX 201.70EPX
2
0
0
.
4
0
EP
20
1
.
0
0

X
EP X 203.33EP202.50 XEPX 202
.50EP199.00 XEP199.52 XEPX 199.52EP202.00 X
EP X 202.0EP199.27 XEPX 199.59EPX 2
01
.
43EP
X 201
.
5
1
EP X 200.45EPX 2
0
0
.
4
5
EP
X 2
0
0
.
3
0
EP
X 200.30EPX 198
.5
FES 10
1
FES 10
0
FES 2
0
0
CB 201CB 202CB 203ADI 204CB 20
6
FES 20
7CB 301CB 401FES 300
FES 400
CB 403
CB 404
CB 208X 19
9
.
5
X 199.5X 199.5X 199.5X 199.5X 199
.5X 194.0DA 203A0.69 ACDA 2020.81 ACX
2
0
1
.
0
X

2
0
1
.
0
DA 20.08 ACFLUME

2
FLUME

1
DA 10.08 ACDA PD 10.48 ACDA PD 2 & 10110.48 ACDA 2040.40 ACDA 2050.65 ACDA 2060.42 ACDA 2079.26 ACDA 2080.90 ACDA 4040.48 ACDA 405 & PD 617.92 ACDA 4010.10 ACDA 3011.49 ACDA 2010.63 AC200200X 201.0X
2
0
2
.
0
X 201.8 X 201
.8DA PD 35.22 ACDA PD 40.93 ACDA PD 58.27 ACCB 402FES 405
X 200.26TOS200.01 XTOSX 199.0X 200.0X 201.0H.P.X 199
.0X 202.0X 194.0X 191.8ROCKFISH ROAD - SR 1403TC FLOW LINE (TYP)TC=16.2 MINTC FLOW LINE (TYP)TC=17.4 MINTC FLOW LINE (TYP)TC=15.0 MINSWEET WILLIAM WAY - SR 1774X 20
1
.
0
0
EP201.1 XEPX 2
0
1
.
0
0
EP 203.00 XEPX 203.00EP2
0
0
200
205 19819819819
8
1
9
9
199
201
201
202
202
203
203 204
204
197 19719819
8 199DI 406
DI 407
DA 4060.43 ACDA 4070.96 ACX 203.0X 203.5X 202.5X 201.5X 201.0X 201.0X 202.0CB 203CB 20
5DA 2030.10 ACX 201.0X 201.0200200
200200200195
195195195200 X 203.5X 20
1
.
0X 199.5X 199
.5200200200200
2
0
0 200200200200X 20
1
.
0 DA 4030.76 ACJB 401AJB 201AJB 301AFile: C:\Users\DDS2\Desktop\Drafting and Design\2019\2019-23 Winchester Subdivsion\2020.04.22 - Winchester Subdivision CDs.dwg Print Date: 10/16/2020
STORMWATER INLET DRAINAGE AREA MAPDA1Drawn by:Designed by:Reviewed by:Date:Scale:Sheet:Project Number:ofREVISIONS NORTH1"=120'2PROFESSIONAL ENGINEER'S SEAL WINCHESTER SUBDIVISION
MTBJRTJRTJULY 24, 2020ROCKFISH ROAD
HOKE COUNTY, NORTH CAROLINA 143 Charlotte Avenue, Suite 104Sanford, North Carolina 27330(919) 777-6010 phonewww.jthomasengineering.comlicense no. C-3389AGENCY REVIEW ONLYJ Thomas Engineering, Inc.civil engineering &planningJTE #:DDS#: 2019-231200120240SCALE: 1" = 120'60
INV.=1
9
6
.
3'
INV.=
1
9
5
.
5
9'CT
TGRAYSTONE LANEHAYL
O
F
T

C
O
U
R
T
CRAFTSMAN COURT
NEWCASTLE COURTDA EC SB #125.6 ACDA EC SB #25.5 ACDA EC TD#67.9 ACDA EC TD#523.27 ACDA EC TD #42.5 ACDA EC TD #32.1 ACDA ECTD #21.2 ACDA EC TD #122.7 ACROCKFISH ROAD - SR 1403TC FLOW LINE (TYP)TC=14.4 MINTC FLOW LINE (TYP)TC=16.8 MINTC FLOW LINE (TYP)TC=12.6 MINSWEET WILLIAM WAY - SR 17742
0
0
200
205 19819819819
8
1
9
9
199
201
201
202
202
203
203 204
204
197 197198199File: C:\Users\DDS2\Desktop\Drafting and Design\2019\2019-23 Winchester Subdivsion\2020.04.22 - Winchester Subdivision CDs.dwg Print Date: 10/16/2020
EROSION CONTROL DRAINAGE AREA MAPDA2Drawn by:Designed by:Reviewed by:Date:Scale:Sheet:Project Number:ofREVISIONS NORTH1"=120'2PROFESSIONAL ENGINEER'S SEAL WINCHESTER SUBDIVISION
MTBJRTJRTJULY 24, 2020ROCKFISH ROAD
HOKE COUNTY, NORTH CAROLINA 143 Charlotte Avenue, Suite 104Sanford, North Carolina 27330(919) 777-6010 phonewww.jthomasengineering.comlicense no. C-3389AGENCY REVIEW ONLYJ Thomas Engineering, Inc.civil engineering &planningJTE #:DDS#: 2019-231200120240SCALE: 1" = 120'60

APPENDIX D

Soil Map—Hoke County, North Carolina
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
7/15/2020
Page 1 of 33871200387130038714003871500387160038717003871800387190038720003872100387220038712003871300387140038715003871600387170038718003871900387200038721003872200676600676700676800676900677000677100677200677300677400677500677600677700677800677900678000678100
676600 676700 676800 676900 677000 677100 677200 677300 677400 677500 677600 677700 677800 677900 678000 678100
34° 58' 37'' N 79° 3' 58'' W34° 58' 37'' N79° 2' 54'' W34° 58' 2'' N
79° 3' 58'' W34° 58' 2'' N
79° 2' 54'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 17N WGS84
0 350 700 1400 2100
Feet
0 100 200 400 600
Meters
Map Scale: 1:7,490 if printed on A landscape (11" x 8.5") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Hoke County, North Carolina
Survey Area Data: Version 17, Jun 4, 2020
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Jul 1, 2018—Jul 31,
2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Soil Map—Hoke County, North Carolina
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
7/15/2020
Page 2 of 3
Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
BaB Blaney loamy sand, 2 to 8
percent slopes
8.9 3.3%
BaD Blaney loamy sand, 8 to 15
percent slopes
9.4 3.5%
CaB Candor sand, 1 to 8 percent
slopes
29.7 11.0%
GoA Goldsboro loamy sand, 0 to 2
percent slopes, Southern
Coastal Plain
16.9 6.2%
LaB Lakeland sand, 1 to 8 percent
slopes
15.3 5.6%
NoA Norfolk loamy sand, 0 to 2
percent slopes
64.9 23.9%
NoB Norfolk loamy sand, 2 to 6
percent slopes
7.9 2.9%
Ra Rains sandy loam, 0 to 2
percent slopes
6.9 2.6%
WaB Wagram loamy sand, 0 to 6
percent slopes
110.7 40.9%
Wo Woodington loamy sand 0.4 0.1%
Totals for Area of Interest 270.9 100.0%
Soil Map—Hoke County, North Carolina
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
7/15/2020
Page 3 of 3

APPENDIX E

FLOOD HAZARD INFORMATION
SPECIAL FLOODHAZARD AREAS
OTHER AREAS OFFLOOD HAZARD
OTHERAREAS
GENERALSTRUCTURES
Without Base Flood Elevation (BFE)
With BFE or Depth
Regulatory Floodway
Areas Determined to be Outside the 0.2% Annual Chance Floodplain
Non-accredited Levee, Dike, or Floodwall
Zone A,V, A99 Zone AE, AO, AH, VE, AR
Zone X
HTTP://FRIS.NC.GOV/FRIS
THE INFORMATION DEPICTED ON THIS MAP AND SUPPORTINGDOCUMENTATION ARE ALSO AVAILABLE IN DIGITAL FORMAT AT
NORTH CAROLINA FLOODPLAIN MAPPING PROGRAM
FLOOD INSURANCE RATE MAPNORTH CAROLINA
PANEL
MAP NUMBER
MAP REVISED
SEE FIS REPORT FOR ZONE DESCRIPTIONS AND INDEX MAP
Cross Sections with 1% Annual ChanceWater Surface Elevation (BFE)
Coastal Transect
OTHERFEATURES
Profile Baseline
Hydrographic Feature
Limit of Study
Limit of Moderate Wave Action (LiMWA)
Jurisdiction Boundary
Accredited or Provisionally AccreditedLevee, Dike, or Floodwall
Coastal Transect Baseline
SCALE
1 inch = 500 feet
Map Projection:
North Carolina State Plane Projection Feet (Zone 3200)
Datum: NAD 1983 (Horizontal), NAVD 1988 (Vertical)
PANEL LOCATOR
LOGO LOGO
NOTES TO USERS
For information and questions about this map, available products associated with this FIRM including
historic versions of this FIRM, how to order products or the National Flood Insurance Program in general,
please call the FEMA Map Information eXchange at 1-877-FEMA-MAP (1-877-336-2627) or visit the FEMA Map
Service Center website at http://msc.fema.gov. An accompanying Flood Insurance Study report, Letter of Map
Revision (LOMR) or Letter of Map Amendment (LOMA) revising portions of this panel, and digital versions of this
FIRM may be available. Visit the North Carolina Floodplain Mapping Program website at http://www.ncfloodmaps.com,
or contact the FEMA Map Service Center.
Communities annexing land on adjacent FIRM panels must obtain a current copy of the adjacent panel as well as
the current FIRM Index. These may be ordered directly from the Map Service Center at the number listed above.
For community and countywide map dates refer to the Flood Insurance Study report for this jurisdiction.
To determine if flood insurance is available in the community, contact your Insurance agent or call the National
Flood Insurance Program at 1-800-638-6620.
Base map information shown on this FIRM was provided in digital format by the North Carolina Floodplain
Mapping Program (NCFMP). The source of this information can be determined from the metadata available in the
digital FLOOD database and in the Technical Support Data Notebook (TSDN).
ACCREDITED LEVEE NOTES TO USERS: If an accredited levee note appears on this panel check with your local
community to obtain more information, such as the estimated level of protection provided (which may exceed the
1-percent-annual-chance level) and Emergency Action Plan, on the levee system(s) shown as providing protection.
To mitigate flood risk in residual risk areas, property owners and residents are encouraged to consider flood
insurance and floodproofing or other protective measures. For more information on flood insurance, interested
parties should visit the FEMA Website at http://www.fema.gov/business/nfip/index.shtm.
PROVISIONALLY ACCREDITED LEVEE NOTES TO USERS: If a Provisionally Accredited Levee (PAL) note
appears on this panel, check with your local community to obtain more information, such as the estimated level of
protection provided (which may exceed the 1-percent-annual-chance level) and Emergency Action Plan, on the
levee system(s) shown as providing protection. To maintain accreditation, the levee owner or community is
required to submit the data and documentation necessary to comply with Section 65.10 of the NFIP regulations.
If the community or owner does not provide the necessary data and documentation or if the data and documentation
provided indicates the levee system does not comply with Section 65.10 requirements, FEMA will revise the flood
hazard and risk information for this area to reflect de-accreditation of the levee system. To mitigate flood risk in
residual risk areas, property owners and residents are encouraged to consider flood insurance and floodproofing
or other protective measures. For more information on flood insurance, interested parties should visit the FEMA
Website at http://www.fema.gov/business/nfip/index.shtm.
LIMIT OF MODERATE WAVE ACTION NOTES TO USERS: For some coastal flooding zones the AE Zone
category has been divided by a Limit of Moderate Wave Action (LiMWA). The LiMWA represents the approximate
landward limit of the 1.5-foot breaking wave. The effects of wave hazards between the VE Zone and the LiMWA
(or between the shoreline and the LiMWA for areas where VE Zones are not identified) will be similar to, but less
severe than those in the VE Zone.
COASTAL BARRIER RESOURCES SYSTEM (CBRS) NOTE
This map may include approximate boundaries of the CBRS for informational purposes only. Flood insurance is not
available within CBRS areas for structures that are newly built or substantially improved on or after the date(s)
indicated on the map. For more information see http://www.fws.gov/habitatconservation/coastal_barrier.html, the
FIS Report, or call the U.S. Fish and Wildlife Service Customer Service Center at 1-800-344-WILD.
CBRS Area Otherwise Protected Area
Channel, Culvert, or Storm Sewer
0.2% Annual Chance Flood Hazard, Areas of 1% Annual Chance Flood with Average Depth Less Than One Foot or With Drainage Areas of Less Than One Square MileFuture Conditions 1% Annual Chance Flood HazardArea with Reduced Flood Risk due to LeveeSee Notes
Zone X
Zone X
Zone X

94841:6,000
%,012 18.2
!(8
1980000 FEET
440000 FEET
1980000 FEET
450000 FEET
1990000 FEET
450000 FEET
1990000 FEET
440000 FEET
This digital Flood Insurance Rate Map (FIRM) was produced through a unique
cooperative partnership between the State of North Carolina and the Federal
Emergency Management Agency (FEMA). The State of North Carolina has
implemented a long term approach to floodplain management to decrease the
costs associated with flooding. This is demonstrated by the State's commitment
to map flood hazard areas at the local level. As a part of this effort, the State of
North Carolina has joined in a Cooperating Technical State agreement with
FEMA to produce and maintain this digital FIRM.
NATIONAL FLOOD INSURANCE PROGRAM))))))))))))ZONE AE
ZONE AE
ZONE AE
ZONE AE
ZONE AE
Stonewall StC
r
a
b
a
p
p
l
e

L
n Braddy RdTrave
n

C
t
Vera Bee DrEastfield Dr
J a r m o n Ct
S
av
an
n
ah
DrJackson LnAlforodo StCotoneastern Ct
Windy Pines
Ct
Bonney Ln
Elnoray DrSwift Creek RdAftonLn
Gilabend Dr
Sherman Dr
Smith St
Boahn St
DeepCreekLnSyrena DrWhite Pine DrYo v e l DrN
C
-
1
4
0
6 Grenedine DrTobagoPlRollingPine
s
Ct
Bagdad RdFadingTrailLnSandy Bottom
L
n
BillWrightRd Marcelle DrT o r tol a Dr
ETwelveOaksRdFa
l
l
ing
T
ree
Rd
Eunice Dr
Overton Rd
Merganser
Pl
N Copper Ck Dr YarmouthDrMix Trail Ln
Mu
m
f
o
r
d

R
d
Laura LnHighviewDr
Kings Rd
H ic kmanCtTyner D r
Etheland Dr
Doda Dr
Jody Ln
Briar Hill Rd
L a k e rid g e D rGr
ana
daRdBelle Boyd DrMallerneeRd
GurneyLnPrive Rd KingLakeRdWayne LnCorse g a n R d
Cayman DrE L a k e R id g e R d
KernstownRd Co
r
de
li
a
CtCleoPlBrushy
Hill
R
dMa
p
l
e
H
i
l
l

L
n
StewartsCreekD
rMa
r
s
h
C
t
W Twelve Oaks RdMyraRdAmber Ln
K in g R dRoc
k
fi
s
h
R
d
i143
i096
i124
i083
i035
i022
i065
i049
CITY OFFAYETTEVILLE370077
HOKE COUNTYUNINCORPORATED AREAS370397
CUMBERLAND COUNTYUNINCORPORATED AREAS370076
152.8
153.5
157.1170.6125.3166.2
160.8
157.5170.6145.0160.2
170.5
144.8
143.3
133.0
129.9
139.1
137.6
i086
i094
i106
i016i119i154i054i141
i047GullyBranch
GullyBranch
GullyBranch
StewartsCreek
StewartsCreek
Stewarts Creek
StewartsCreek
79°2'30"W
79°2'30"W
79°3'0"W
79°3'0"W
79°3'30"W
79°3'30"W
79°4'0"W
79°4'0"W
34°59'0"N 34°59'0"N
34°58'30"N 34°58'30"N
34°58'0"N 34°58'0"N
MOORE COUNTY
SCOTLAND COUNTY
ROBESON COUNTY
HARNETT COUNTY
8480 9400 9421 9431 9441 9451 9460
8464 8484
8466 8486 9406 9427 9437 9447 9457 9467 9477
9502 9522 9542 9552
8580 9500 9520 9541 9551 956095409550
8479 8488 9408 9428 9448 946884688478
9426 9436 9446 9456 9466 9476
9404 9425 9435 9445 9455 9465 9475 9485
9424 9434 9444 9454 9464 9474 9484
8482 9402 9422 9442 9463 9473 9483
9462 9472 9482
9420 9430 9440 9450
8399 9308 9328 9348
I
0 500 1,000250Feet
0 150 30075
Meters
BM5510 D North Carolina Geodetic Survey bench mark
BM5510 ?
BM5510z
National Geodetic Survey bench markContractor Est. NCFMP Survey bench mark
Panel Contains:
COMMUNITY CID PANEL SUFFIX
9484CUMBERLAND COUNTY 370076 K
9484FAYETTEVILLE, CITY OF 370077 K
9484HOKE COUNTY 370397 K
3710948400K
01/05/07
SITE

APPENDIX E

© 2020 Google
© 2020 Google
© 2020 Google
SITE
APPENDIX E
SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
1 Project Name Glen Meadow Subdivision - Phase 2
2 Project Area (ac)30.71
3 Coastal Wetland Area (ac)
4 Surface Water Area (ac) 0
5 Is this project High or Low Density? Low
6 Does this project use an off-site SCM? No
7 Width of vegetated setbacks provided (feet) 30
8 Will the vegetated setback remain vegetated? Yes
9 Is BUA other that as listed in .1003(4)(c-d) out of the setback? Yes
10 Is streambank stabilization proposed on this project? No
11 Infiltration System 0
12 Bioretention Cell 0
13 Wet Pond 0
14 Stormwater Wetland 0
15 Permeable Pavement 0
16 Sand Filter 0
17 Rainwater Harvesting (RWH) 0
18 Green Roof 0
19 Level Spreader-Filter Strip (LS-FS) 0
20 Disconnected Impervious Surface (DIS) 0
21 Treatment Swale 0
22 Dry Pond 0
23 StormFilter 0
24 Silva Cell 0
25 Bayfilter 0
26 Filterra 0
FORMS LOADED
27 Name and Title: Jeremy Thomas, PE. - President
28 Organization: J Thomas Engineering, Inc.
29 Street address: 143 Charlotte Avenue, Suite 104
30 City, State, Zip: Sanford, NC 27330
31 Phone number(s): [phone]
32 Email: [e-mail]
Certification Statement:

Designer
______________________________________________
Signature of Designer
______________________________________________
Date

I certify, under penalty of law that this Supplement-EZ form and all supporting information were prepared under my direction or
supervision; that the information provided in the form is, to the best of my knowledge and belief, true, accurate, and complete; and
that the engineering plans, specifications, operation and maintenance agreements and other supporting information are consistent
with the information provided here.
PROJECT INFORMATION
NUMBER AND TYPE OF SCMs:
DESIGNER CERTIFICATION
COMPLIANCE WITH 02H .1003(4)
Seal
DRAINAGE AREAS
1 Is this a high density project?No
2 If so, number of drainage areas/SCMs 4
3
Is all/part of this project subject to previous rule
versions? No
FORMS LOADED
Entire Site 1
4Type of SCM
5 Total BUA in project (sq ft)203039 sf
6
New BUA on subdivided lots (subject to permitting)
(sq ft)115500 sf
7
New BUA outside of subdivided lots (subject to
permitting) (sf)104039 sf
8 Offsite - total area (sq ft) sf
9 Offsite BUA (sq ft) sf
10 Breakdown of new BUA outside subdivided lots
- Parking (sq ft)
- Sidewalk (sq ft)8149 sf
- Roof (sq ft)
- Roadway (sq ft)79390 sf
- Future (sq ft)

- Other, please specify in the comment box below
(sq ft)
11
New infiltrating permeable pavement on subdivided
lots (sq ft)
12
New infiltrating permeable pavement outside of
subdivided lots (sq ft)
13
Exisitng BUA that will remain (not subject to
permitting) (sq ft)
14 Existing BUA that is already permitted (sq ft)
15 Existing BUA that will be removed (sq ft)
16 Percent BUA 15%
17 Design storm (inches)
18 Design volume of SCM (cu ft)
19 Calculation method for design volume
20
Entire Site 1
4 Type of SCM N/A
5 Total BUA from project (sq ft)
6 1995 rules
SL 2006-246
2008 rules
2017 rules
7
New BUA on subdivided lots (subject to
permitting) (sq ft)
1995 rules
SL 2006-246
2008 rules
2017 rules
8
New BUA outside of subdivided lots (subject to
permitting) (sf)
1995 rules
SL 2006-246
2008 rules
2017 rules
9 Offsite - total area (sq ft)
1995 rules
SL 2006-246
2008 rules
2017 rules
10 Offsite BUA (sq ft)
1995 rules
SL 2006-246
2008 rules
2017 rules
11 Design storm (inches)
1995 rules
SL 2006-246
2008 rules
2017 rules
DRAINAGE AREA INFORMATION
DRAINAGE AREA INFORMATION
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
drainage area(s):
12 Breakdown of new BUA:
- Parking (sq ft)
- Sidewalk (sq ft)
- Roof (sq ft)
- Roadway (sq ft)
- Future (sq ft)

- Other, please specify in the comment box below
(sq ft)
13
New infiltrating permeable pavement on subdivided
lots (sq ft)
14
New infiltrating permeable pavement outside of
subdivided lots (sq ft)
15
Exisitng BUA that will remain (not subject to
permitting) (sq ft)
16 Existing BUA that is already permitted (sq ft)
17 Existing BUA that will be removed (sq ft)
18 Percent BUA
19 Design volume of SCM (cu ft)
20 Calculation method for design volume
21
Please use this space to provide any additional
information about the drainage area(s):
ADDITIONAL INFORMATION
LOW DENSITY
1 Yes
2 Yes
3 Yes
4 5TO1
5
6 Yes
7 0%
8 2 ft
9 5:1
10 290 ft
11 No
12 No
13 Yes
14 No
15
Swale
#
Drainage
Area
(ac)
BUA
(ac)
Pervious
area
(ac)
C Q
(cfs)
Slope
(%)
Vallow             
(fps)
Vactual            
(fps)Flow depth (ft)
1 9.47 0.16 9.31 0.35 21.63 0.50 4.56 3.60 1.38
2 --------- -
3 21.79 2.32 19.47 0.30 51.57 0.10 4.56 2.29 1.74
4 2.43 0.57 1.86 0.40 8.07 0.10 4.56 1.36 0.68
5 29.41 1.31 28.10 0.30 57.39 0.60 4.56 4.33 1.82
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
Does project maximize dispersed flow and minimize channelization of flow?
Is project below density thresholds set forth in the applicable stormwater rule?
DESIGN REQUIREMENTS FOR LOW DENSITY PROJECTS FROM 02H .1003
ADDITIONAL INFORMATION
Has the use of piping been minimized per .1003(2)(c)?
Are treatment swales used instead of curb outlet swales?
Minimum length of curb outlet swale(s) (feet)
Maximum side slope of curb outlet swale(s) (H:V)
Bottom width of curb outlet swale(s) (feet)
Maximum longitudinal slope of curb outlet swale(s) (%)
Are curb outlet swales proposed?
Maximum velocity in the vegetated conveyances during the 10-year storm?
Side slopes of the vegetated conveyances (H:V)
Are variations to rule .1003 proposed?
Have stormwater outlets been designed to prevent downslope erosion?
Is stormwater released at the edge of the setback as dispersed flow?
Please use this space to provide any additional information about this low density project:
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 1 of 2
Project name
Contact name
Phone number [phone]
Date
Drainage area number
Site Characteristics
Drainage area 413,384.00 ft2
Impervious area 7,200.00 ft2
Percent impervious 1.7%%
Design rainfall depth 3.04 inch
Peak Flow Calculations
10-yr storm runoff depth 5.44 in
10-yr storm intensity 5.26 in/hr
Post-development 10-yr storm peak flow 14.97 ft3/sec
Velocity
Maximum non-erosive velocity (peak 10-year storm)4.50 ft/sec
Soil characteristics (enter "x" below)
Sand/silt (easily erodible)X
Clay mix (erosion resistant)
Grass Type (enter "x" below)
Bermuda
Tall fescue X
Bahiagrass
Kentucky bluegrass
Grass-legume mixture
Swale type: Fill out one of the options below:
Option 1: Curb Outlet Swale:Y (Y or N)
Maximum velocity 3.60 OK
Side slopes 4.00 :1 Insufficient side slopes. Max is 5:1.
Swale length 240.00 ft OK
Option 2: Swale Seeking Pollutant Credit ("For-Credit" Swale):(Y or N)
Maximum velocity for 10-yr storm ft/sec
Side slopes :1
Swale length ft
II. DESIGN INFORMATION
This form must be filled out, printed and submitted.
PD 1
The Required Items Checklist (Part III) must also be filled out, printed and submitted along with all of the required information.
July 15, 2020
Winchester Subdivision
J Thomas Engineering, Inc - Michael Blakley
GRASSED SWALE SUPPLEMENT
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
I. PROJECT INFORMATION
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 2 of 2
Swale Characteristics
Swale Shape: Enter an "x" in the appropriate cell below:
Trapezoidal
Parabolic
V-shaped X
Width of the bottom of the swale ft
Width of the top of the swale ft
Additional Information
Is the swale sized for all runoff from ultimate build-out?Y (Y or N)OK
Is the BMP located in a proposed drainage easement with a
recorded access easement to a public Right of Way (ROW)?Y (Y or N)OK
What is the distance from the bottom of the swale to the SHWT?1.00 ft OK
What is the ground level elevation?200.00 fmsl
What is the elevation of the bottom of the swale?197.00 fmsl
What is the SHWT elevation?196.00 fmsl
What is the longitudinal slope of the swale?0.50 %OK
What is the depth of freeboard?0.62 ft OK
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 1 of 2
Project name
Contact name
Phone number [phone]
Date
Drainage area number
Site Characteristics
Drainage area 1,055,023.00 ft2
Impervious area 101,228.00 ft2
Percent impervious 9.6%%
Design rainfall depth 3.04 inch
Peak Flow Calculations
10-yr storm runoff depth 5.44 in
10-yr storm intensity 5.26 in/hr
Post-development 10-yr storm peak flow 36.83 ft3/sec
Velocity
Maximum non-erosive velocity (peak 10-year storm)4.50 ft/sec
Soil characteristics (enter "x" below)
Sand/silt (easily erodible)X
Clay mix (erosion resistant)
Grass Type (enter "x" below)
Bermuda
Tall fescue X
Bahiagrass
Kentucky bluegrass
Grass-legume mixture
Swale type: Fill out one of the options below:
Option 1: Curb Outlet Swale:Y (Y or N)
Maximum velocity 2.29 OK
Side slopes 5.00 :1 OK
Swale length 480.00 ft OK
Option 2: Swale Seeking Pollutant Credit ("For-Credit" Swale):(Y or N)
Maximum velocity for 10-yr storm ft/sec
Side slopes :1
Swale length ft
II. DESIGN INFORMATION
This form must be filled out, printed and submitted.
PD 3
The Required Items Checklist (Part III) must also be filled out, printed and submitted along with all of the required information.
July 15, 2020
Winchester Subdivision
J Thomas Engineering, Inc - Michael Blakley
GRASSED SWALE SUPPLEMENT
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
I. PROJECT INFORMATION
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 2 of 2
Swale Characteristics
Swale Shape: Enter an "x" in the appropriate cell below:
Trapezoidal X
Parabolic
V-shaped
Width of the bottom of the swale ft
Width of the top of the swale ft
Additional Information
Is the swale sized for all runoff from ultimate build-out?Y (Y or N)OK
Is the BMP located in a proposed drainage easement with a
recorded access easement to a public Right of Way (ROW)?Y (Y or N)OK
What is the distance from the bottom of the swale to the SHWT?2.00 ft OK
What is the ground level elevation?198.00 fmsl
What is the elevation of the bottom of the swale?195.00 fmsl
What is the SHWT elevation?193.00 fmsl
What is the longitudinal slope of the swale?0.10 %OK
What is the depth of freeboard?0.26 ft OK
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 1 of 2
Project name
Contact name
Phone number [phone]
Date
Drainage area number
Site Characteristics
Drainage area 105,850.00 ft2
Impervious area 24,983.00 ft2
Percent impervious 23.6%%
Design rainfall depth 3.04 inch
Peak Flow Calculations
10-yr storm runoff depth 5.44 in
10-yr storm intensity 5.26 in/hr
Post-development 10-yr storm peak flow 36.83 ft3/sec
Velocity
Maximum non-erosive velocity (peak 10-year storm)4.50 ft/sec
Soil characteristics (enter "x" below)
Sand/silt (easily erodible)X
Clay mix (erosion resistant)
Grass Type (enter "x" below)
Bermuda
Tall fescue X
Bahiagrass
Kentucky bluegrass
Grass-legume mixture
Swale type: Fill out one of the options below:
Option 1: Curb Outlet Swale:Y (Y or N)
Maximum velocity 1.36 OK
Side slopes 5.00 :1 OK
Swale length 290.00 ft OK
Option 2: Swale Seeking Pollutant Credit ("For-Credit" Swale):(Y or N)
Maximum velocity for 10-yr storm ft/sec
Side slopes :1
Swale length ft
II. DESIGN INFORMATION
This form must be filled out, printed and submitted.
PD 4
The Required Items Checklist (Part III) must also be filled out, printed and submitted along with all of the required information.
July 15, 2020
Winchester Subdivision
J Thomas Engineering, Inc - Michael Blakley
GRASSED SWALE SUPPLEMENT
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
I. PROJECT INFORMATION
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 2 of 2
Swale Characteristics
Swale Shape: Enter an "x" in the appropriate cell below:
Trapezoidal X
Parabolic
V-shaped
Width of the bottom of the swale ft
Width of the top of the swale ft
Additional Information
Is the swale sized for all runoff from ultimate build-out?Y (Y or N)OK
Is the BMP located in a proposed drainage easement with a
recorded access easement to a public Right of Way (ROW)?Y (Y or N)OK
What is the distance from the bottom of the swale to the SHWT?1.50 ft OK
What is the ground level elevation?198.50 fmsl
What is the elevation of the bottom of the swale?195.00 fmsl
What is the SHWT elevation?193.50 fmsl
What is the longitudinal slope of the swale?0.10 %OK
What is the depth of freeboard?2.32 ft OK
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 1 of 2
Project name
Contact name
Phone number [phone]
Date
Drainage area number
Site Characteristics
Drainage area 1,281,099.00 ft2
Impervious area 56,992.00 ft2
Percent impervious 4.4%%
Design rainfall depth 3.04 inch
Peak Flow Calculations
10-yr storm runoff depth 5.44 in
10-yr storm intensity 5.26 in/hr
Post-development 10-yr storm peak flow 57.39 ft3/sec
Velocity
Maximum non-erosive velocity (peak 10-year storm)4.50 ft/sec
Soil characteristics (enter "x" below)
Sand/silt (easily erodible)X
Clay mix (erosion resistant)
Grass Type (enter "x" below)
Bermuda
Tall fescue X
Bahiagrass
Kentucky bluegrass
Grass-legume mixture
Swale type: Fill out one of the options below:
Option 1: Curb Outlet Swale:Y (Y or N)
Maximum velocity 4.33 OK
Side slopes 5.00 :1 OK
Swale length 550.00 ft OK
Option 2: Swale Seeking Pollutant Credit ("For-Credit" Swale):(Y or N)
Maximum velocity for 10-yr storm ft/sec
Side slopes :1
Swale length ft
Winchester Subdivision
J Thomas Engineering, Inc - Michael Blakley
GRASSED SWALE SUPPLEMENT
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
I. PROJECT INFORMATION
II. DESIGN INFORMATION
This form must be filled out, printed and submitted.
PD 4
The Required Items Checklist (Part III) must also be filled out, printed and submitted along with all of the required information.
July 15, 2020
Permit Number:________________
(to be provided by DWQ)
Form SW401-Grassed Swale-Rev.4 Parts I and II. Project Design Summary, Page 2 of 2
Swale Characteristics
Swale Shape: Enter an "x" in the appropriate cell below:
Trapezoidal X
Parabolic
V-shaped
Width of the bottom of the swale ft
Width of the top of the swale ft
Additional Information
Is the swale sized for all runoff from ultimate build-out?Y (Y or N)OK
Is the BMP located in a proposed drainage easement with a
recorded access easement to a public Right of Way (ROW)?Y (Y or N)OK
What is the distance from the bottom of the swale to the SHWT?1.50 ft OK
What is the ground level elevation?197.50 fmsl
What is the elevation of the bottom of the swale?194.00 fmsl
What is the SHWT elevation?192.50 fmsl
What is the longitudinal slope of the swale?0.60 %OK
What is the depth of freeboard?1.18 ft OK