20071658 Ver 2_Stormwater Info_20080404

Soil & Environmental Consultants, PA
Transmittal
To: VN NVIV\
z.32a c-a _ 7\vd.
We Transmit to you Herewith:
® Drawings
? Specifications
? Brochures or photos
® Correspondence
? As per your request
Project #: Jkq-+,D? Date: LA/Lk/()'g
Project Name: T -? W Goal ?c
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? Returned for correction, resubmit
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Remarks:
If enclosures are not as listed as above, kindly notify us at once.
By: V??CC1 Q Mckcc?'WSC)
c:
APR 4 201)8
DENARW STW
V?ETLA tA AiiR BKMCH
?'?
Soil & Environmental Consultants, PA
11010 Raven Ridge Road • Raleigh, North Carolina 27614 • Phone: [phone] • Fax: [phone]
www.SandEC.com
April 4, 2008
Project 9197.D1
DWQ Project No.: 07-1658 Johnston County
Mr. Ian McMillan
401 Oversight and Express Permits Unit
NCDENR Division of Water Quality
2321 Crabtree Boulevard
Raleigh, NC 27604
Reference: Request for More Information
Taftwoods East - Section 2
Johnston County, NC
Dear Mr. McMillan,
With this letter we are submitting updated construction drawings for the stormwater management
plan of the above referenced project.
Per the request for more information (attached), these plans have been stamped and are suitable
for construction. Additional detail information has been provided for the contractor to construct
the concrete level spreader and wet detention pond outlet structure.
The request for more information also stated that the level spreader for Drainage Area # 6 (Sheet
10 of 16) appears to have a slope of greater than 8%. Based on the contours and lengths shown
on the drawings, this filter strip begins at an elevation of approximately 193.5' and ends between
approximately 188' (at the most northern point) and 186' (at its most southern point). The length
of the strip (perpendicular to the contours) at its most northern point is approximately 100' and
this length divided into an elevation drop of 5.5' yields a slope of 5.5%. The length of the strip at
the most southern end is approximately 130' and this length divided into an elevation drop of
7.5' yields a slope of 5.8%. These slopes fall under the maximum slope of 6% for a forested
filter strip. Please let me know if you need any more information concerning the slope of this
filter strip, but based on these calculations the location of this level spreader has not been
modified.
Also enclosed is a CD containing the entire submittal in a grouped TIF format (black and white).
Please note that nothing has changed in the stormwater design or BMP's. Only the detail sheets
have been updated with additional information for the contractor that was necessary for the plans
to be stamped and ready for construction.
If you have any questions concerning this submittal, please do not hesitate to contact us.
Sincerely,
SOIL &F
kin
ANTS, PA
Rebecca S. Peterson, P
NCPE 31266
5EAL
= Q31266 •
Attachments: Construction Drawings (5 sets)
CD with Black and White Submittal Data
Cc: Lauren Witherspoon, DWQ Raleigh Regional Office
?QF NIATF9Q Michael F. Easley, Governor
G William G. Ross Jr., Secretary
(q North Carolina Department of Environment and Natural Resources
>
Q '< Coleen H. Sullins, Director
Division of Water Quality
March 14, 2008
DWQ Project # 2007-1658v2
Iredell County
CERTIFIED MAIL: RETURN RECEIPT REQUESTED
Mr. George Schlecht -?
Lauraleen, LLC
3 515 Queen Ann Drive 04 R Fnoronm?ntal Consultants, F'.
Clayton, NC 27527
Subject Property: Taftwoods East - Section 2, Clayton, NC
UT to Mill Creek [030402, 27-39, C, NSW
REQUEST FOR MORE INFORMATION
Dear Mr. Schlecht:
On February 4, 2008, the Division of Water Quality (DWQ) received your application and level spreader
designs dated February 4, 2008 to impact 3,056 square feet (ft) of Zone 1 protected riparian buffers and
711 square feet (ft) of Zone 2 protected riparian buffers to construct the proposed level spreaders. The
DWQ has determined that your application was incomplete and/or provided inaccurate information as
discussed below. The DWQ will require additional information in order to process your application to
impact protected wetland, streams and/or buffers on the subject property. Therefore, unless we receive
the additional information requested below, we will have to move toward denial of your application as
required by 15A NCAC 2H .0506 and 213 .0233(8) and will place this project on hold as incomplete until
we receive this additional information. Please provide the following information so that we may continue
to review your project.
Additional Information Requested:
1. According to plan sheet 10 of 16, the filter strip downslope of level spreader 6 appears to have
greater than 8 percent slope. Please relocate this level spreader to a location with appropriate slopes
or provide a properly designed BMP that removes 85 percent of TSS and 30 percent of Total
Nitrogen and Total Phosphorous. If you choose to provide a BMP, please submit the appropriate
BMP Supplement Form with all required items attached.
2. The plans should be the final construction drawings and these plans are labeled "Preliminary - Not
for Construction." Please revise your plan sheets to reflect this change.
Please respond within three weeks of the date of this letter by sending this information to me in writing
and Lauren Witherspoon of the DWQ Raleigh Regional Office. If we do not hear from you within three
weeks, we will assume that you no longer want to pursue this project and we will consider the project as
withdrawn.
This letter only addresses the application review and does not authorize any impacts to wetlands, waters
or protected buffers. Please be aware that any impacts requested within your application are not N ` C
oarolina
Morally
401 Oversight/Express Permitting Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] / FAX [phone] / Internet: h!W://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer - 50% Recycled/] 0% Post Consumer Paper
Applicant:
Page 2 of 2
Date:
authorized (at this time) by the DWQ. Please call Ms. Amy Chapman or Mr. Ian McMillan at 919-733-
1786 if you have any questions regarding or would like to set up a meeting to discuss this matter.
Sincerely,
Cyndi Karoly, Supervisor
401 Oversight/Express Review Permits Unit
CBK/ijm/asc
cc: Lauren Witherpsoon, DWQ Raleigh Regional Office
S&EC, Attn: Rebecca Peterson, 11010 Raven Ridge Rd, Raleigh, NC 27614
File Copy
Central Files
Filename: 071658v2Taft W oodsEast(Johnston)On_Hold
DESIGN CALCULATIONS
Soil & Environmental Consultants; PA S&EC Project No 9197.A1
Taft Woods East January 2028
Project Location
The project site is located in Johnston County, NC. The property is owned by Neuse
Park Development Company and consists of approximately 126 acres located 0.2 miles
west of the intersection of Motorcycle Road and NC Highway 42 East. See Figures 1 and
2.
Stormwater Plan
Level spreaders are proposed for the distribution of concentrated stormwater on this
residential development in order to comply with the diffuse flow requirements within the
Tar-Pamlico River Basin. Proposed impervious for this projects drainage area is 15 %e as
indicated in the 401 Water Quality Certification Application. As such, no specific
stormwater treatment is required for this project beyond diffuse flow requirements. The
401 Water Quality Certification was approved October 15, 2007:
A total of seven (7) drainage areas were evaluated for stormwater runoff and level
spreader sizing. In one case; a small detention pond is proposed to buffer the runoff peak
and allow for the controlled release of stormwater through a level spreader. Where
necessary, pipes will be used to convey stormwater from the roadside swales to level
spreaders. All proposed pipe, level spreader, and detention pond locations are shown on
the attached Construction Drawings. The level spreader design is based on guidance
from the July 2007 NCDENR-DWQ BMP manual.
Level Spreader Planning & Design
Calculations for the sizing of level spreaders and their components were performed by
Soil & Environmental Consultants, PA (S&EC). All necessary stormwater design
calculations and supporting documentation are attached:
Based on existing and proposed topography, the site was divided into seven (7) different
drainage areas. Stormwater captured from each of the contributing watersheds is
conveyed (primarily through grass-lined roadside ditched designed by Dennis Ray
Blackmon, R.L.S.) to an appropriate level spreader location where it can be released in
the form of diffuse flow through the adjacent stream buffer (or equivalent filter strip)
upslope and outside of a stream buffer.
All of the level spreaders were sized based on the total contributing drainage area for the
1-inch/hour design rainfall. Utilizing the Rational Equation, we then calculated a design
discharge for each drainage area. Based on this discharge and the vegetation in the
downslope buffer, the length of the level spreader was then calculated. All but one
(Drainage Area 3) of the calculated level spreader lengths fell within the acceptable
range. The level spreader that exceeded the maximum length was redesigned such that a
wet detention basin that would collect the stormwater, detain it, and only release a
discharge suitable for the maximum level spreader length (in this case 130 feet). The
outlet of the wet detention basin to the level spreader will be at a rate that allows the level
I of 3
Soil & Environmental Consultants, PA S&EC: Project No 9197.D1
Taft :Woods :East January 2008
spreader length to fall within the acceptable range. No forebay will accompany this level
spreader since the forebay of the wet detention basin will provide the necessary settling
of suspended sediments. This wet detention basin was designed to store and outlet the
10-year event (at the appropriate allowable discharge rate) to the level spreader, and as
such, no bypass channel will be required for this level spreader either.
For the remainder of the level spreaders, bypass channels have been designed to convey
the discharge associated with a 10-year event in accordance with the September 2007
BMP manual. Attached is the required Preconstruction Notice for the Riparian Buffer
Authorization for each of the bypass channels.
The forebays in this project have been designed to settle suspended sediments as well as
to split the stormwater flow to the level spreader and the bypass channel. The forebays
have been fitted with an appropriately sized pipe that discharges to the swale upstream of
the level spreader. Each pipe is sized for the discharge associated with the 1-inch/hour
storm event for the watershed and is anchored in a concrete wall that discharges to the
level spreader as shown in the Construction Drawings. For each flow splitter, the pipe
was sized using the orifice equation where the discharge calculated with the maximum
head (depth of water) above the pipe was sized to the discharge of the 1 inch/hour storm.
The invert of the bypass channel from the forebay was set at a specific height above the
invert elevation of the pipe leading to the level spreader. The vertical distance between
the bypass channel invert and the pipe invert was set to be equal to the maximum desired
head (water depth) above the pipe. This design allows any flow entering the forebay up
to and equaling the 1 inchihour storm to flow through the pipe to the level spreader.
Once the flow entering the forebay exceeds the 1 inch/hour storm, the bypass channel
will be activated. Again, each bypass channel was sized to convey discharges up to and
including the 10-year event.
Based on the soils located at the proposed level spreader locations, all of the swales
located upslope of the level spreaders will naturally drain within 24 hours; and therefore
no underdrains are necessary. Caution will be applied during construction to reduce the
potential for compaction of underlying soils. Site soils were deemed sufficient to drain
naturally based on permeabilities greater than 0.6 inches per hour:
2 of3
Soil & Environmental Consultants; PA S&ECProject No 9197.D1
Taft. Woods East January 2008
List of Attachments and Figures
Attachments°
1. Level Spreader and Wet Detention Pond Calculations 36 pages
II. NCDENR Level Spreader, Filter Strip, and Restored Riparian Buffer
Supplement Worksheets; Checklists, and Photos of Proposed Level
Spreader Locations 28 pages
III. Filter Strip, Restored Buffer, and Level Spreader Inspection
Maintenance Agreements 25 pages
IV. Riparian Buffer Authorization Pre-construction Notice 19 pages
Figures
Figure 1 --USES Map
Figure 2 - Soils Map & Aerial Photo
Flan Sheets:
Sheet 1- Cover, Contents, & Vicinity Map
Sheet 2 - Existing Site Conditions
Sheet 3 - Proposed Development
Sheet 4- Proposed Stormwater BMP Drainage Areas
Sheet 5 - Proposed Site Conditions Sheet DA #1
Sheet 6 - Proposed Site Conditions Sheet DA #2
Sheet 7 - Proposed Site Conditions Sheet DA #3
Sheet 8 - Proposed Site Conditions Sheet DA #4
Sheet 9- Proposed Site Conditions Sheet DA #5
Sheet 10 - Proposed Site Conditions Sheet DA #6
Sheet I 1 - Proposed Site Conditions Sheet DA 47
Sheet 12 - Construction Sequence & Temporary Seeding Specifications
Sheet 13 - Level Spreader & Flow Splitter Details
Sheet 14 - Erosion Control Details
Sheet 15 - Wet Detention Basin Details
Sheet 16 - Emergency Spillway & Outlet Protection Apron Details
3:of:3.
SOIL & ENVIRONMENTAL ENTAL CONSULTANTS, PA
ATTACHMENT
LEVEL SPREADER AND WET DETENTION POND CALCULATIONS

Level Spreader Design Spreadsheet
DA#1..: :.:. ::::............................... ..........................................
Taft Woods
S&EC:Project No. 9197.D1
1. Determine Contributing Impervious Area and Iin/hour Discharge Rate
1. Weighted Rational Coefficient,: C = F[C,*%A]
:
L;:=: Rational coefficient for development area i
A=Area
Total Drainage Area = 5.02 acres::::
Development Area .(it'): Area (ac.): %Area Rational C: %Area 'C::
Lots:- : Impervious :(roof, parking,: etc.) 27582.25: 0.633 : 12.6% 0.95 0120
Lots - Forested 0.00 0.000 0.0% 0.15 0.000
Lots- Lawn (maintained grass) 123377.48 2.832 56.5% 0.2 0.113
Impervious (Roads)28776.55:.:0.66113.2%00.95 0.125:::
Road Easements (maintained grass) 38781.55 0.890 17.7% 0.2 0.035
total 218517.83 5.016 0.393
weighted rational: coefficient,: C= 0.393::
::::.:... impervious drainage area.=....56358.79.
total drainage area =..... 218517.83 ft'
2. Discharge Rate, Q:= C*i*A, cfs
Rational Equation, Applied Hydrology by Chow, pp. 497
:C = Weighted rational coefficient
:i=Rainfall intensity
:A= Drainage area,fte
C= 0.393
I _ ...1.00 in/hour
A 5.02 acres
Q=.1.97 cfs....
11. Sizing the Forebay:
Forebay Area, Aro,abay = 0.2%(Aimn) ft2
Amp: = Contributing: impervious area, ft2
Aim, =: 56358.79 ftz
A,,,, = 112.72 ftz
III. Determine Level Spreader Length & Slope Check
:**Choose one of the following,.a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation '- 13 feet of level spreader per l cis of flow
b: Forested with little/no ground cover vegetation and 50-foot vegetated buffer '--65 feet of level spreader per4 cis of flow
c: Forested with little/no ground cover: vegetation and 100-foot: vegetated buffer :'--50. feet of level spreader peril. cis of flow:
d:: Forested with little/no ground. cover: vegetation and 150-foot vegetated buffer '--40. feet of level spreader per? cfs of flow:
Cover: b (a, br c, or d from above)
Total. discharge,: Q= 1.97 cfs
Length of level spreader =.. ..128.29 it
Check Level. spreader is within allowable length requirements of greater than 13 feet and less than .130 feet.
Pagel. DA .1 :::
s. = Slope of ground downslope of level spreader = [Elev.u,s-Elev ojs)/L, ftlft
Elev.us Elevation at level: spreader, it
Elev.ws.=. Elevation at stream bank (or: at the edge of a: 50' vegetated buffer or fi lter strip), ft
L = Length from level spreader to stream (or edge: of 50' buffer or filter step), ft
Elev.ws = 209.15 it
Elev.ois = : 205.75 it
L=...71.54..ft .................................. ......... ........ ........ ...................
a=0.0475 ft/ft.
..Check: Slope is less than 6%.
IV. Determine Bypass Channel Design Flow (Riprap Lined or Grass Swale)
1 Time of Concentration, T. = 0.0078-L 1.71SI.111, min
Kirpfch Equation,: Applied Hydrology by Chow, pp. 500:::
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (ft)
:S= Average: slope =:H/L(ftlft)::
L = 1206.9 it
H .::70.0 ft.::::
S = 0.058 ft/ft....
T,= 5.51 min:..
2. 10-Year Storm intensity. i1Q based on Intensity-Duration-Frequency (IDF) Table
i10 =10-year. intensity that occurs at the time of concentration, T.
TABLE1.INPUT:
.: :Location: :Taft Woods East
Duration 2 yr : .100 yr Source
(in).. (in...
5min... .:0.48: 0.81 NOAA Hydro 35 :......... ......... ........ ........ ...................
15 min::: 1.03: 1.88NOAA Hydro 35
60 min::: : 1.83 3.80 NOAA Hydro 35
24 hr 3.70 8.30 USWB TP 40
:TABLE 2 DEPTH:- DURATION - FREQUENCY TABLE 3.: INTENSITY: -:DURATION - FREQUENCY
Duration 2 yr : 10 yr100 Yr 2 yr 10 yr.:: 100 yr
H-1 * (in) (in) (in) Duration (in/hr) (in/hr) (in/hr)
5 min * 0.48: 0.60 0.81 5 min 5.80.. .. 7.22 9.68
10 min 0.81 : 1.051.44::: 10 min 4.83 6.28 8.64
15 min * 1.03.... 1.36.... 1.88 ................ 15 min..... ... 4.12.. .. 5.42... . 7.52............. .
30 min 1.42: 1.97 2.82 30 min 2.84.. .. 3.94... . 5.64
60 min *:: 1.83: 2.613.80::: 60 min 1.83 2.61 3.80
2 hr * 2.04 2.94 : 4:30::: 2 hr 1.02 1.47 2.15
3. hr:.:.. 2.24 3.26:... 4.79 ................ .3 hr 0.75.. .. 1.09... . 1.60............. .
6 hr *... 2.77 4.09 6.05 6 hr 0.46.. .. 0.68... . 1.01
12 hr:*::: 3.23: 4.827.18::: 12 hr 0.27 0.40 0.60
24 hr.*....... 3.70.... 5.56.... 8.30 ................ 24 hr 0.15.. .. 0.23... . 0.35............. .
From Eqs. 111-(1-3), p.III-(4-5), Stormwater Management: Vol.l Intensity= Depth / Time
Urban Hydrology. B.H.Bradford, N.S.Grigg, L.S. Tucker
T, _ 5.51. min
3. 10-Year Discharge Rate, Q, =C*il0*A, cfs
C= Weighted rational coefficient
110= Rainfall intensity associated with 10-year storm, in/hour
A = Drainage area,. fts
C= 0.393
m =.::7.22 in/hour::
:A=5.02 acres
:
.Q10 14.26 ofs::
Paget. DA1 :::
V. Bypass Channel Specifications
1. Calculated Depth of Flow using Normal-Depth Procedure
s:=:Channel slope= [Elev.uimElevas]/L,:ft/ft
Elev.urs =: Elevation: at level spreader, ft
Elev,?s = Elevation at stream bank, ft
L Length of channel from level spreader to stream, ft
Elev.ws= 209. ft
Elev.ais = 204 ft
L=84.23 ft.....
s.=..0.0594 ft/ft .:...........................................................................
2 Bypass Channel Dimensions (for trapezoidal channel)
a) Cross-sectional Area, A. = Q,ON,, ftz
Qm = 10-year design flow, cfs
Va = Chosen to be less than the maximum allowable channel velocity, :5 fps for the:10-yr event: according to the NC Erosion &
Sediment: Control: Planning and Design: Manual: table 8.05a for a Bermudagrass: lined channel
Q, 14.26 cfs
Va 5: fps.:::
A. = ..2.85. ftz
b) Working Constant, w, M -.2*q{1+Mzl
:.:........................................................................
M = Side slope ratio (H:V)
M= 3 H:1V:::
w, : -3.32.: (will: always be negative)
c) Working Constant, wz A.l[[(V,*n)/(1.49vk)f2]
A„ = Channel cross-sectional area, ft2
Va = Chosen to be less than the maximum allowable velocity
n Manning's roughness coefficient [0:030 for grass-lined; 0.033 for riprap-lined (Applied Hydrology by Chow, Table 2.5.1, pp. 35)
]
s= Channel slope, rift
A. ` 2,85: ftz
V. 5: fps.:::
n ..0.030
a = 0.0594 ft/ft
w2 =10.73
d) Depth of Flow, d = [-w2 * 4w22+4w,A.)]/2w,, It wy Working constant
wz = Working constant
A, = Channel cross-sectional: area, ftz
Wi -3.32
W2 .10.73
A.` 2,85: ftz.::::
d.= 0.292 ft
e) Bottom Width of Channel, B = A?/tl M*d, ft::
A, = Channel cross-sectional area, ftz
d= Depth of flow, ft M = Side slope ratio (H:V)
A. ° 2.85 ftz
..............................................................................
d.=.. 0.292 ft
M- 3H:1V.
B.=... 8.89...n.....
Page 3: :DA1 :::
f) Top Width of Channel t = B*(2'd'M), it B = Bottom width of channel, ft
:d= Depth of flow, it t ---------------W :::: :::: :::
M = Side slope ratio (H.V)
B- 8.89 ft d J.1.
d= 0.292 ft
M= 3H:1V...
t=10.64 ft ............................. 8.'...............................
3. Velocity Check
a) Wetted Perimeter, P:=: 8+2dv[M,+1], it
B = Bottom width of channel, ft
d= Depth of flow, it M=Side slope ratio(H:V) .............................................................................
B= 8.89 ft
d= 0.292 ft
M= 3H:1V.::
P=: 10.73 ft
b) Hydraulic Radius: R = A/P
A, =Channel cross-sectional area, ftz
:P = Wetted Perimeter, ft
A, - 2.85 ftz
P 10.73 ft.....
R 0.266 ft
S
c) Bypass Channel Velocity, v = (1.49/n)-R?13- S1/2, fps
--velocity must be less than 5 fps according toE&S Control Planning and Design Manual - Grass-Lined Channels
n:=. Manning's: roughness coefficient [0.030 for grass-lined; 0.033: for riprap-lined (Applied: Hydrology by Chow, Table 2.5.1, pp. 35)]::::
:R = hydraulic radius, wetted cross-sectional . area (A) / wetted pereimeter (P), ft
s= Channel slope, Rift
n .0.030
..............................................................................
R= 0.266 ft
a= 0.059 ft/ft.
V = 5.00.. fps
Check. Velocity is within allowable maximum velocity for Bermndagrasstining. Atemporary lining of erosion control
matting will be used for stabilization until grass is established.
d) For this depth, the resulting shear stress is then
Shear Stress,: T=yds, Ib/ftz::
y:=. Unit weight of water, 62.4 Iblit3
:.
d= Flow depth, ft
.::::
sd Channel gradient, ft/ft
y = 62.40 lb/ft'
d=....:0.29 ft..
s= 0.059 ft/ft
T= : 1.1. Ib/ftz.
This shear stress is under the permissible unit shear stress (2 lbiftz) for synthetic mat (erosion control matting) as stated in the NC
Erosion& Sediment Control Planning and Design Manual, Table 8.05g:
VI. Flow Splitter (Forebay) Specifications
Using the orifice equation, 0 = Cd.A.(2<g.h)(n2) a) Pipe Cross-sectional Area, Apia, = [a14]d2, ftz:
d = Diameter of pipe from forebay to flow splitter, in
d= 8. inches.:
A,j, 0.3489 ftz
Page 4 DA 1 ::
b) Head Above Bypass Pipe, h = [(Q/(Cd*A))2 1/2*9, it
(solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
Q = Discharge, cfs (1: in/hr discharge)
Ca Discharge coefficient (0.6 for sharp-edged orifice]
Appe =: Pipe cross-sectional: area, ft2
g:=: Gravitational acceleration, ft/s2
h: Height of water: above: the orifice (head), it Q= 1,97 cis
Ca= 0.6:
A0, 0.3489 ft'.
32.2 ft/s2::::
h= 1.38 it
VII. Swale Drainage Calculations
The following calculations: use Darcy's law to calculate the time (in hours) that it will take for the:swale upslope: of the.::::
level spreader: to naturally drain based on the permeability of the in-situ soils.
a) Surface Area Draining to In-Situ Soil, A = L*W, ft2
L= Level spreader length, ft
W= Width of swale upslope of level spreader, ft
L=..12829 ft.::::
W= 3:. ft.....
A= .384.86 W
b) Groundwater Flow, Q = (K*i*A)/43200, cfs Darcy's Law
K= Average coefficient of permeabiilty,.in/hr :[4 in/hr based on Pacolet Loam soils from 0 to 8: inches in depth]:
-based on the Johnston County: Soil Survey (NRCS)
i = Hydraulic gradient [assumed to equal 1]
A = Surface area draining to in-situ soil, ft2
K :4m/hr:::
A = 384.86 ft2.::::
Q= 0.0356 cfs..
c) Volume Draining to an Situ Soil, V = d*A, ft2
d= Depth of water draining to in-situ soil, in
A = Surface area draining to in-situ soil, ft
d= 5. in.
A = 384.86 ft2.::::
V = 192.43 fts.:...
d) Time to Drain the Swale VIQ, sec
V = Volume drained, ft3
Q = Groundwater: flow, cis
V = 192.43 ft3
Q = 0.0356 cfs
Td=.::5400 s.::::
Td=1.50 hr.
Check: Since: the water held in the:swale after the level spreader has been activated will naturally drain in less than 24
hours, no underdrain will. be. necessary.
Pages. DA1
Level Spreader Design Spreadsheet
DA #2
Taft Woods
:.S&EC Project No. 9197.D1 ..................................... ......................................... .
1. Determine Contributing Impervious Area and :1 in/hour: Discharge. Rate
1. Weighted Rational Coefficient, C = E(C;*%A;]
C =Rational coefficient for development area
A =Area
Total Drainage Area 1.23acres
Development Area (ft 2) Area (ac.) % Area Rational C % Area * G
Lots- Impervious (roof,.parking, etc.) 7400.32. 0.170. 13.8%. 0.95. 0.131
....Lots Forested 0.00... 0.000.... 0.0% 0.15 0.000
Lots-Lawn (maintained grass) 28982.12 0.665 54.0% 0.2 0.108
Impervious (Roads) 6913.90 0.159 12.9%a 0.95 0.122
Road. Easements (maintained grass) 10386.99: 0.23819.3%:: : 0.2 0.039::
total: 53683.34 1.232 .................. .. 0.400
weighted rational coefficient; C =...0.400..
impervious drainage area = 14314.22 ft
...total drainage: area = 53683.34 ft2
2. Discharge Rate, Q = C*i*A, cfs::
Rational Equation,. Applied: Hydrology by Chow, pp. 497:::
C = Weighted rational coefficient
i = Rainfall intensity (typical 1 in/hour)
A = Drainage area, ft2
C = 0.400:
1=...1.00 inthour ................................ ...........................................
A= 1.23 acres.::
Q=... 0.49.. cis
..
IL Sizing the Forebay
Forebay Area, Abrebe, = 0.2%(A?.), ft2
A,o, = Contributing impervious area, k2
Aimp. = 14314.22 ftz

.
klebay 28.63 ft2
III Determine Level Spreader Length & Slope Check
**Choose one of the following,: a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation '--13 feet of level spreader per 1 cis of flow
b: Forested: with little/no ground cover vegetation and 50-foot vegetated buffer '--65 feet of level spreader per 1 cis of flow
c: Forested with little/no ground cover vegetation and 100-foot vegetated buffer '--50 feet of level spreader per 1 cis of flow
d: Forested with little/no ground cover vegetation and 150-foot vegetated buffer '--40 feet of level spreader per l cis of flow
Cover. b (a b, c, or d from above)
::::... Total discharger Q = 0.49 cfs
Length of level: spreader =... 32.04: ft
Check: Level spreader Is within allowable length requirements of greater than 13 feet and less than 130 feet.
Page 1.: DA2
s = Slope of ground downslope of level spreader = [Elev., Elev.nj/L, ft/ft
Elev.uls = Elevation at level spreader, ft.::
Elev.o/s = Elevation at stream bank (or at the edge of a 50' vegetated buffer or filter strip), ft
L = Length from level spreader to stream (or edge of 50' buffer or filter strip), it
Elev.,,, 234.36
Elev.as:=.: 229.97
L=73.52
:
..................................
s=.. 0.0598 . ......... ........ ......... .................
Check: Slope is less than 6%..::::
IV. Determine Bypass Channel Design Flow (Riprap Lined or Grass Swale)
1. Time of Concentration T.:=:0.0078*Lo.r7S-oa8s min
Kirpich:Equation. Applied Hydrology by. Chow,. pp. 500:
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (it)
S =.Average slope = H/L(ft/ft)
L=...511.0 ft::::
H=...28.0 ft::::
S =0.055 ft/ft
T?=.::2.90 :min::
2.: 10-Year Storm Intensity, i10 based on Intensity-Duration-Frequency : (IDF) Table
i, = 10-year intensity that occurs: at the time of concentration, T.
TABLEI.INPUT
...:
:..............................
Location: Taft Woods East
.........
........
.........
.................
Duration: 2 yr 100yr Source
(in) (in)
5 min 0.48 0.81 NOAA Hydro 35
15 min:. 1.03 1.88- NOAA Hydro 35 ::......... ......... ........ ......... ............... .
60 min : 1.83 3.80 NOAA Hydro 35
24 hr::: 3.70 : 8.30USW6 TP 40
TABLE 2. DEPTH - DURATION - FREQUENCY TABLE 3 . INTENSITY -DURATION - FREQUENCY
Duration : 2 yr : 10 yr: 100 yr 2:yr 10 yr 100 yr
H-1* (in) (in): (in):: Duration (m/hr) (in/hr) (in/hr}
5 min:*: 0.48.... 0.60.... 0.81 ................ .5 min..... ... 5.80.. . 7.22.... 9.65............ .
10 min.. .. 0.81 1.05 1.44. 10 min 4.83.. . 6.28.... 8.64.
15 min:*: 1.03 : 1.36: 1.88:: 15 min 4.12 5.42 7.52.::::
30 min 1.42 1.97 2.82 ................ 30 min..... ... 2.84.. .. 3.94.... 5.64............ .
60 min:*: : 1.83 2.61 3.80.: 60 min 1.83.. . 2.61.... 3.80.::::
2 hr * 2.04 2.94: 4.30 2 hr 1.02 1.47 2.15.::::
3 hr: ` 2.24 : 3.26: 4.79:: 3 hr 0.75 1.09 1.60.::::
6 hr * 2.77.... 4.09.... 6.05 ................ .6 hr 0.46.. .. 0.68.... 1.01............ .
12 hr * 3.23 4.82 7.18.: 12 hr 027.. . 0.40.... 0.60.::::
24 hr: * 3.70 : 5156 8.30:: 24 hr 0.15 0.23 0.35.::::
From Eqs.:III-(1-3), p.III-(4-5),: Stormwater Management: Voll.:::: Intensity= Depth/Time:
Urban Hydrology.B.H.Bradford, N.S..Grigg,LS. Tucker
T,=.. 5.00 min::
3.: 10-Year Discharge Rate, Qjo.= C*ilo*A, cfs
CWeighted rational coefficient
i1o: _ Rainfall intensity: associated: with 10-year storm, in/hour
ADrainage: area, ft2
C=...0.400
ho = 7.22 in/hour
A-... 1.23 acres:
..:Paget DA2
CIO- 3.56 cfs.::::
V. Bypass Channel Specifications
1. Calculated Depth of Flow using Normal-Depth Procedure
s = Channel slope =.[Elev.uis-Elev.os]/L, ft/ft
Elev.ws = Elevation at level spreader, it Elev.,,s = Elevation at stream bank, ft
L = Length of channel from level spreader to stream it::::
Elev:ws = 234.39: it Elev:ors = 230.86: ft
L= 65.07. it s 0.0542 Rift.
2. Bypass: Channel Dimensions (for trapezoidal channel)
a). Cross-sectional. Area, A, = Q,%, ft2
Q10 =:10-year design flow, cfs:::
Ve =: Chosen to be less than the maximum allowable channel: velocity, 5 fps for the 10-yr event according to the NC Erosion
Sediment Control Planning and Design Manual table 8.05a for a Bermudagrass lined channel::::
:.CIO=...3.56 cfs.::::
Va= 3.4: fps
A,- 1.05. ft2
b) Working Constant,. w, = M - 2*41+M?]
M = Side slope ratio (H.V)
M= 3 H:1V
W l - -3.32: (will always be negative)
c) working constant,. w, = A,/[[(V,*n)/(1 49,?)]srz]
A,:=: Channel cross-sectional area, 02
V,:=: Chosen to be less than the maximum allowable velocity
n = Manning's roughness coefficient [0.030: for grass lined:; 0.033 for riprap lined:(Applied Hydrology by Chow,: Table 2.5. 1, pp. 35)
s = Channel slope, ft/ft
:.A, = 1.05. it'
Vs= 4.5. fps
n=...0.030.
s= 0.0542 ft/ft.
w2= ..4.32:
d) Depth: of Flow, d =:[-w2 +,(w22+4w,A,)]/2wi, ft
w, =Working constant
w2= Working constant
A, Channel cross-sectional area, ft2
W, = ..-3.32:
w2= ..4.32:
:Ax= 1.05 ft`
d = 0.323. ft
e) Bottom Width of Channel, B = Ajd.- M*d :ft
A, Channel cross-sectional area, ft2
d = Depth of flow, ft
:M = Side slope ratio (H:V)
Ax= 1.05. ft2
d= 0.323. ft
:
M= ::::3 HIV
Page 3 DA 2
B=...2.27.. ft..
f) Top Width of Channel, t = B+(2*d*M), ft:::
B Bottom width ofchannel, ft .........................................................................
d = Depth of flow, ft t
MSide slope: ratio (H:V):::
B = 2.27 ft d
d = 0.323 ft
t= ... 4.21 ft.:.. Imo.... B
3. Velocity Check::
a) Wetted Perimeter, :P = B+2d4M2+11, ft:::
6:=:Bottom width of channel, ft
d = Depth of flaw, ft
M= Side slope ratio (H;V)
B.=...2.27 ft.:::
d=...0.323 ft.:::
M 3H:1V:
P=4.32 ft....
b) Hydraulic Radius, R= A/ P
Ax = Channel cross-sectional area, ft2
P=Wetted Perimeter, ft.:::
A„-..1.05 ft2...
P=...4.32 ft::::
R0.243 ft:...
c) Bypass Channel Velocity, v = (1 49/n)*R2r3.Suz fps :...
'--velocity must be less than 5 fps according to E&S Control Planning and Design Manual - Grass-Lined Channels
n =Manning's roughness coefficient [0.030 for grass-lined; 0.033 for riprap-lined (Applied Hydrology by Chow, Table: 2.5.1, pp. 35)]
R:=: Hydraulic radius, wetted. cross-sectional area (A) /wetted pereimeter (P),: it s = Channel slope, ft/ft ..... :.... .
n 0.030
R.=...0.243..ft .............................................................................
s=...0.054 ft/ft
:::....V=... 4.50.. fps...
Check: Velocity is within: allowable maximum velocity for Bermudagrass lining. A temporary : lining of erosion control
matting will be used for stabilization until grass is established:
d) For this depth, the resulting shear stress is then:
Shear Stress, T:= yds, lb/ftz::
y= Unit weight: of water, 62.4 ib/ft3
d= Flow depth, ft
s = Channel gradient, ft/ft
y 62.40 : Ib/ft3
d=.....0.32.....ft ..........................................................................
s= ...0.054 ft/ft
T= 1,1 Iblft2
This shear stress is under the permissible unit shear stress (2 lb/ftz) for synthetic mat (erosion control. matting) as stated in the NC
Erosion &Sediment Control Planning and Design Manual, Table 8.05g.
VI. Flow Splitter (Forebay) Specifications
Using the orifice equation, Q = Cd*A*(2*g*h)(1 12)
a) Pipe Cross-sectional Area Apwo = In/41d2, ftz
d =Diameter of pipe from Forebay to flow splitter, in
:Page4 DA2
d= 4.. inches.::
Apipe - 0.0872 it'
b) Head Above Bypass Pipe, h: = [(Q/(Cd*A)ft2*g, ft
(solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
Q = Discharge, eta (I in/hr discharge) Cd:=. Discharge: coefficient [0.6 for sharp-edged orifice]::::
Apips = Pipe cross-sectional area, ft2
g = Gravitational acceleration, ft/s2
h = height of water: above: the orifice (head), ft
.::::
Q= 0.49 eta
:.Cd= 0:6::
Aippe - 0.0872 ft°
g= 32.2 ft/s2
h=...1.38. ft......
VII. Swale Drainage Calculations
The following calculations use Darcy's law to calculate the time (in hours) that it will take for the Swale
upslope of the level spreader to naturally drain based on the permeability of the insitu soils.
a) Surface Area Draining to In-Situ Soil, A = L*W, ft2
L = Level spreader length, ft....
W Width of Swale upslope of level spreader, ft
L= 32.04. ft
W = 3.. ft
::::::.....A=...96.12.. ft:.....
b) Groundwater Flow, Q = (K*i*A)/43200 cfs Darcy's Law:
K = Average coefficient of permeability; in/hr [1.3 in/hr based on Pacolet Loam soils from 5 to 25 inches in depth]
based on the Johnston County Soil Survey (NRCS)
i:=: Hydraulic gradient [assumed . to equal 1]:::
A = Surface area draining toxin-situ soil, ft2
K= 1:3 in/hr.
i= 1
:A= .:96.12 ft2.....
Q= 0.0029 ofs.: ............................................................................
c) Volume Draining to In-Situ Soil, V = d*A, ft?
d = Depth of water draining to in-situ soil, in
A = Surface area. draining toxin-situ soil, ft::::
d= 6.. in
A = 96.12. ft2
V = .:48.06. ft3
d) Time to Drain the Swale = VIC,.sec
V = Volume drained, W
Q = Groundwater flow, cfs
V= 48:06: ft'
Q=0.0029 cis ..............................................................................
Ta= 16615. s
Ta = 4.62 hr
Check: Since the water held in the Swale after the level spreader has been activated will naturally drain in lessthan 24
hours, no underdrain will be necessary..:::
Page 5 :: DA2: :::
Level Spreader Design Spreadsheet
DA #3
Taft Woods
S&EC Project No. 9197.131
1. Determine Contributing Impervious Area and 1inlhour Discharge Rate
1. Weighted Rational Coefficient, C = E[C;*%A;]
C = Rational coefficient for development area
A =Area
Total Drainage Area = 13.78 acres
Development Area (ft`) Area (ac.) %Area Rational C %Area * C SCS Cure # %Area *Curve #
Lots - Impervious (roof, parking, etc.) 74992.63 1.722 12.51 0.95 0.119 98 12.240
Lots - Forested 9401 0.216 1.6% 0.15 0.002 55 0.861
Lots - Lawn (maintained grass) 407666.91 9.359 67.9% 02 0.136 69 46.848
Impervious (Roads) 47660.51 1.094 7.9% 0.95 0.075 98 7.779
Road Easements (maintained grass) 6071781 1.394 10,1% 0.2 0.020 69 6.977
total: 600437.86 13.784 0.352 74705
weighted rational coefficient C = q.352
impervious drainage area = 12265314 its
total drainage area = 600437.86 W
Discharge Rate, Q = C*i*A: cis
Rational Equation, Applied Hydrology by Chow, pp. 497
C = Weighted rational coefficient
i = Rainfall intensity
A = Drainage area, fir
C = 0.352
i = 1.00 in/hour
A = 13.78 acres
Q= 4.86 ids
Ill. Determine Level Spreader Length. & Slope Check
-Choose one of the following, a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation '--13 feet of level spreaderper l cis of flow
b: Forested with littlelno ground cover vegetation and 50-toot vegetated buffer '--65 feet of level spreader per 1 cis of flow
c: Forested with littlelno ground cover vegetation and 100-foot vegetated buffer '--50 feet of level spreader per I cis of flow
d: Forested with littlelno ground cover vegetation and 150-foot vegetated buffer '--40 feet of level spreader per 1 cis of flow
Cover; b is, b, c, or d from above)
Total discharge, Q = 4.86 cis
Length of level spreader = 315.76 ft
Check: LEVEL SPREADER LENGTH HAS EXCEEDED MAXIMUM ALLOWABLE LENGTH, 130 FEET. SEE SECTION VI.
s = Slope of ground downslope of level spreader = [Elev.,,s-Elev.efs]iL, ft/ft
Elev,rs = Elevation at level spreader, ft
Elev.o;s = Elevation at stream bank (or at the edge of a 50' vegetated buffer or filter strip), ft
L = Length from level spreader to stream (or edge of 50' buffer or filter strip), ft
Elev.'s = 183
Elev.,;, 180 At
L = 65 it
s = 0.0462 Will
Check: Slope is less than 6%.
Page 1 DA 3
IV. Hydrology Data
1. Time of Concentration, T, = 0.0078'L0 778-0 385, Min
Ktrpich Equation, Apptied Hydrology by Chow, pp. 500
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (ft)
S = Average slope = H/L (ft/ft)
L= 1381.6 ft
H = 73.0 It
S = 0.053 ft/ft
T,= 6.34 min
2. 10-Year Storm Intensity, i10 based on Intensity-Duration-Frequency (IDF) Table
110 = 10-year intensity that occurs at the time of concentration, T,
TABLE 1. INPUT
Location: Taft Woods East
Duration: 2 yr 100 yr Source
(in) (in)
5 min 0.48 0.81 NOAA Hydro 35
15 min 1.03 1.88 NOAA Hydro 35
60 min 1.83 3.80 NOAA Hydro 35
24 hr 3.70 8.30 USth'B TP 40
TABLE 2. DEPTH - DURATION - FREQUENCY TABLE 3.INTENSITY -DURATION -FRE QUENCY
Duration 2 yr 10 yr 100 yr 2 yr 10 yr 100 yr
H-1 * (in) (in) (in) Duration (in/hr) (inlhr) (in/hr)
5 min' 0.48 0.60 0.81 5 min 5.80 7.22 9.68
10 min 0.81 1.05 1.44 10 min 4.83 6.28 8.64
15 min * 1.03 1.36 1.88 15 min 4.12 5.42 7.52
30 min 1.42 1.87 2.82 30 min 2.84 3.94 5.64
60 min * 1.83 2.61 3.80 60 min 1.83 2.61 3.80
2 hr * 2.04 2.94 4.30 2 hr 1.02 1.47 2.15
3 hr * 2.24 326 4.78 3 hr 0.75 1.09 1.60
6 hr * 2.77 4.09 6.05 6 hr 0.46 (168 1.01
12 hr * 3.23 4.82 7.18 12 hr 0.27 0.40 0.60
24 hr * 3.70 5.56 8.30 24 hr 0.15 0.23 0.35
From Eqs. III-d-3), p. 111-(4-5), Stor mssater Ma nagement: Vol I Intensity= Depth I Time
Urban Hydrology. B.H.Bradford, N.S.Grigg, L.S. Tucker
T„= 6.34 min
3. 10-Year Discharge Rate, Q,c = C*i.r*A, cfs
C = Weighted rational coefficient
i,p = Rainfall intensity associated with 10-year storm, in/hour
A = Drainage area, ftz
C = 0.352
i10= 7.22 in/hour
A = 13.78 acres
Qua= 35.09 cfs
V. Wat Detention Pond Sizing
The 1 iWhr flow for this drainage area (and any resonable subdivisions of it) results in a level spreader that exceeds the maximium
length. To remedy this, a wet detention basin is proposed that will have an orifice sized to outlet the discharge associated with the
maximum level spreader length (130 feet, in this case). The wet detention basin will have a permanent pool. Above this elevation,
the detention basin has been designed with enough storage volume to store the 10-yr event and discharge this volume to the level
spreader at the rate associated with the maximum level spreader length. Based on this design, no bypass channel, flow splitter, or
forebay will be needed at this level spreader.
The Simple Method, from section 3.3.1 of the September 2007 BMP Manual, is used to osculate the volume of runoff from the 10-yr
storm.
Solving for V (volume of runoff in fta that must be controlled for the design storm) the Simple Method is:
V = 3630*Rd*Rv*A
Page 2 DA 3
Where:
Rd= Design storms rainfall -in this case 1.05 in based on table 2 above rounding up to a duration of 10 min from a Tc of 6.34 min.
A = Watershed area in acres
Rv = Runoff coefficient calculated as:
Rv = 0.05 + 0.9*la
Where Is = the imperious fraction = (the impervious portion of the drainage area) ! (the total drainage area)
Therefore:
Is = 0.20
Rv = 0.23
V = 12,183.05 W
This storage is less than the storage provided between the permenant pool elevation and the emergency spillway elevation
(47,042 ft3) of the proposed wet detention basin as shown in the attached Stage-Storage Calculations, therefore, the
proposed wet detention basin is sufficiently sized to store the volume from the 10-yr event and release it to the level
spreader at 2 cis (see section VI).
VI. Wet detention Pond Orifice Sizing
The maximum discharge from the wet detention basin to the level spreader is calculated as 2 cfs based on the maximum allowable
level spreader length of 130 feet, in this case. (For forested with little or no ground cover and a 50 foot vegetated buffer, 65 feet of
level spreader is needed per 1 cis of flow. Based on this, 2 cis is the discharge associated with the maximum level spreader length
of 130'). Using this Q and the maximum head from the wet detention basin design, h, the orifice equation can be used to solve for
the area of the orifice in the riser that outlets to the barrel to the level spreader:
Q = Cd.A*(2*9*h)nv2
Q = Discharge - in this case it will be set to 2 cis
Cd = Discharge coefficient = 0.6
A = Area of orifice draining the wet pond, fts
g = Acceleration due to gravity, Weis
In = Maximum height of water above the orifice (head), ft (in this case h = 2 ft based on design)
Therefore, solving for the area of the orifice:
A = Ql(Cd"(2*g"h)^'c)
A = 0.24 ft
d = 0.55 ft (diameter of circular orifice)
d = 6.63 in
VII. Wet detention Pond Outlet Barrel Sizing
Outflow Pine Diameter, Dmn = 16*[(Q"n)iw5]I'"1: (ft)
Q = Flow to level spreader. (2 cfs)
n = Manning's roughness coefficient
s = internal slope (recommended minumum 0.5%)
Qm = 2.00 cfs
n = 0.012 for HDPE CPP double wall, smooth interior
s = 0.50°{
Df,.1= 10.67 inches
Based on this, the Outlet Barrel will be specified with a 12 inch diameter.
VIII. Swale Drainage Calculations
The following calculations use Darcy`s law to calculate the time (in hours) that it will take for the Swale upslope of the level spreader
to naturally drain based on the permeability of the in-situ soils,
a) Surface Area Draining to to-Situ Soil, A = L*W, fe
L = Level spreader length, It
W = Width of Swale upslope of level spreader, It
L = 130.00 ft
W = 3 ft
A = 390.00 ft`
Page 3 DA 3
b) Groundwater Flow, Q = (K`I'A)?43200, cis Darcy`s Law
K = Average coefficient of permeablilty, in/hr [4 in/hr based on Wehadkee Loam soils from 0 to 7 inches in depth]
based on the Johnston County Soil Surrey (MRCS)
i = Hydraulic gradient [assumed to equal 1]
A = Surface area draining to in-situ soil, ftc
K = 4 inlhr
i= 1
A = 390.00 fiz
Q = 0.0361 cis
c) Volume Draining to In-Situ Soil, V = cM ft`
d = Depth of water draining to in-situ soil, in
A = Surface area draining to in-situ soil, ft
d = 6 in
A = 390.00 it'
V = 195.00 ft3
d) Time to Drain the Swale = V/Q, sec
V = Volume drained, ft3
Q = Groundwater flow, cis
V = 195.00 ft`
Q = 0.0361 cfs
Tv = 5400 s
T,, = 1.50 hr
Check: Since the water held in the swale after the level spreader has been activated will naturally drain in less than 24
hours, no underdrain will be necessary.
IX. Spillway Channel Design Hydrology
The emergency spillway is sized to convey the 100-year event. We are assuming that no storage wilt be provided by the pond for
the 100-year event, and therefore, this flow has not been routed through the pond.
a) 100-Year Storm Intensity, i,cc based on Intensity-Duration-Frequency (IDF) Table from Section IV.2
i,cs = 100-year intensity that occurs at the time of concentration, Tc
T„ = 6.34 min
imo= 9.68 in/hour
b) 100-Year Discharge Rate, Q,c = C'i,c"A cis
C = Weighted rational coefficient
i,cc = Rainfall intensity associated with 100-year storm, in/hour
A = Drainage area, fe
C = 0.352
i,cc = 9.68 inlhour
A = 13.78 acres
Q+ec = 47.04 cis
X. Calculated Depth of Flow using Normal-Depth Procedure
a) s = Channel slope = [Elev.r,rs-Elev.os]IL, ft/ft
Elev,uls = Upstream reference elevation, ft
Elev.o,s = Upstream reference elevation, ft
L = Length of channel from upstream to dowstream, ft
Elev.us = 191 It
Elev.es = 185 ft
L = 57 ft
s = 0.1053 Wit
Page 4 DA 3
b) A = Trapezoidal channel area = W'd + Mdz, fti
P = Wetted perimeter = W + 2d, it
R = Hydraulic radius = A/P, ft
W = Bottom width of channel, ft
of = Channel depth, ft
M = Side slope ratio (H:V)
Rearranged Manning's Equation: AWv' = Qn/[1 a 9",,5]
0100 = Design flow over spillway, cfs
n = Manning's roughness coefficient
s = Channel slope
Q•,, ° 47,04 cfs M =
n = 0.033 for riprap-lined channel
s = 0.1053 Wit
! Qnl[1.49*l?] = 3.211 1
"*need to find d so that AR"' = 4n/[1 49'*y5]
d W A P R AR21'r
1 20 23.00 22 1.045 23.692
0.5 20 10.75 21 0.512 6.879
0.4 20 8.48 20.8 0.408 4.662
0.35 20 7.37 20.7 0.356 1700
0.34 20 7.15 20.68 0.348 3.520
0.33 20 6.93 20.66 0.335 3.343
0.335 20 7.04 20.67 0.340 3.431
0.325 20 6.82 20.65 0.330 3.256
.0.3224 20 6.76 20.6448 0.327 3.211
Based on this calculated depth, the emergency spillway will pass the
100 year event without overtopping since its desi gn depth is 1.0 feet
N.I. Shear Stress Calculations
b) Channel shear stress, Tu,, = YH2o*d*Scn,, Ib/ft`
Yrrm = Unit weight of water, Ib/ft'
d = Channel depth, ft
5,,;,, = Channel slope, ft/ft
YH2 = 62.4 lb/ft'
d = 0.322 If
S, = 0.1053 ft/ft
Tin. = 2.118 Ib/ft2
3 HAV
_ Actual Channel dimensions:
W = 20 ft
According to Table 8.058 of the NCDENR Erosion and Sediment Control Manual, this is a
permissable shear stress for a riprap liner with a do, of 9 inches or greater.
This corresponds with Class 1 Rip Rap as defined in Table 1042-1 of the NCDOT Standard
Specifactions for Roads and Structures, 2002
Page 6 DA 3
STAGE-STORAGE RELATIONSHIP::: STA-STO.WB2 J L E:. VER 05-97, P.K.SMOD. 09-02, P K S:. MOD. 08-06
Taft Woods Drainage Area #3
S&EC Project No..9197 D1 Wet Detention Basin
:::.:.. STORAGE ABOVE PERMENANT POOL
SUA410ARYEQUATIOiN:
Regression Output., Ks
S=Ks Zb Constant 10.007 22185
where:S Storage Volume, ft.3 b
Z Stage above Invert, ft X Coefficient(s) 1.084::
Ks is defined by regression output : ........
b is defined by regression output
Incremental Storage : Computed Computed
Contour Area Z AREA dH Volume (Acc. 1.),S In(Z) In(S) Storage In(S)
(Elev.) (Acres) (fee#) (ft ft.) . .... (ft')... ....(fts) .......... ....... ... (ft)

......
..........189..0 0.47 0.0 20433
.........
................
.......
........
........
190.0 0.55 1.0.::23938 : 1 22185: 221850.000 .10.007 22,185: .:10.007:
191.0 0.59 2.025774 1:: 24856: .:47041 0.693 10.759: 47,041: 10.759:
.::::. ..Page 6 : DA3
Level Spreader Design Spreadsheet
DA.#4.
Taft Woods
S&EC Project No. 9197.D1
1. Determine Contributing Impervious Area and lin/hour Discharge Rate
1 Weighted Rational Coefficient, C = F[Ci*%oA;]:
C = Rational coefficient for development area
A=Area
Total Drainage Area = 1.11 acres
Development Area (ft z) Area (ac:) % Area Rational C % Area * C
Lots - Impervious (roof, parking, etc.) 3242.99 0.074 6.7% 0.95 0.064
Lots- Forested .1050.00: 0.0242.2%a0.15 0.003::::
Lots - Lawn (maintained grass) : 22536:.38 0.517 46.5% 0.2 0.093
Impervious (Roads) 9897.12 0.227 20.4% 0.95 0.194
Road Easements (maintained grass) 11687:00 0.268 24.1% 0.2 0.048
total: 48413.49: 1.1.11::: 0.402::::
weighted rational coefficient, C = 0.402.:
impervious: drainage area 13140.11 ftz
total drainage area =.... 48413.49 ftz
2. Discharge Rate. Q = C*i*A, cfs
Rational Equation, Applied Hydrology by Chow, pp. 497
C = Weighted rational coefficient
= Rainfall intensity
A = Drainage area,:ftz
C .0.402
I=... 1.00... in/hour ................................ ...........................................
A= 1.11 acres:::
::::.::.... Q.=... 0.45.. cfs....
11. Sizing the Forebag.
Forabay Area, A,ebay 0.2%b(Aim,.), ftz
Aim, -= Contributing impervious area, ftz
Aim, = 13140.11 ftz
Almebay = : 26.28 ftz :.....
III. Determine Level Spreader Length & Slope Check
**Choose one of the following,:a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation '--13 feet of level spreader per l cfs of flow
bi :Forested with little/no ground: cover vegetation and 50-foot: vegetated buffer '-65 feet of level spreader per 1 cis of flow
c: Forested with little/no ground cover vegetation and 100-foot vegetated buffer '--50 feet of level spreader per ? cis of flow
d: Forested with little/no ground cover vegetation and 150-foot vegetated buffer '-40 feet of level spreader per 1 cis of flow
.:Cover: : b : (a, b,: c, or d from above)
Total discharge. Q = 0.45 cfs
Length of level spreader = 29.08 It
Check: Level spreader is within allowable length requirements of greater than 13 feet and less than 130 feet.
Pagel. DA4 :::
s. = Slope of ground downslope of level spreader = [Elev./s-Elev.?js]/L, ftIft
:Elevuws =. Elevation at level: spreader, ft
Elev.,s.=. Elevation at stream bank (or: at the edge of a: 50' vegetated buffer or filter strip), ft
L = Length: from level spreader to stream (or edge: of 50' buffer or filter strip) ft
Elev:we = 178.38 ft
Elev.ois = 177.24 ft
L=...55.59..ft ................................. .......... ........ ........ ...................
S = 0.0204 fl/ft.:..
Check: Slope is less than 6%.
IV. Determine Bypass Channel Design Flow (Riprap Lined or Grass Swale)
1 Time of Concentration, T. = 0.0078'L"'S' "' mm
Kirpich Equation,: Applied Hydrology by Chow, pp 500:::
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (ft)
:S = Average: slope =:H/L(ft/ft)::
L=698.0 ft.
H=30.0 ft.::::

................................
S= 0.043 ft/ft
..........
........
........
...................
:To = 4.06 min
2 40-Year Storm Intensity, i10 based on Intensity-Duration-Frequency (IDF) Table
I, =.10-year intensity that occurs at the time of concentration, T.
TABLE1.INPUT:
.: .Location: :Taft Woods East:::
Duration 2 yr : 100 yr:: Source
(in).. (in)...
5 min:.. .:0.48: 0.81 NQAA Hydro 35 .......... .......... ........ ........ ...................
15 min:: 1.03: : 1.88NOAH Hydro 35
60 min::: : 1.83 3.80 NOAA Hydro 35
24 hr.... 3.70 8.30 USWBTP 40
:TABLE 2. DEPTH:- DURATION -. FREQUENCY TABLE 3. :INTENSITY - DURATION: -:FREQUENCY:
Duration... 2 yr 10. yr 100 yC 2 yr :: ..10 yr 100 yr
H-1 *:. (in) (in) (in) Duration : (in/hr).. : (in/hr)..: .(in/hr)
5 min* 0.48 0.60 0.81::: 5min 5.80 7.22 9.68
10 min 0.81 1.051.44::: 10. min 4.83 6.28 8.64
15 min ....... 1.03.... 1.36.... 1.88 15 min 4.12.. .. 5.42... . 7.52 ..............
30 min... 1.42 1.97 2.82 30 min 2.84 3.94 5.64
60 min* .... 1.83: 2.61 3.80::: 60: min 1.83 2.61 3.80
2hr*:: 2.04 2.94: 4.30:: : 2 hr 1.02 1.47 2.15
3. hr:*:.. 2.24 3.26:. 4.79:.......... : 3.hr...... ...0.75 1.09:.. 1.60 ............. .
6 hr *... 2.77 4.09 6.05.:: 6 hr 0.46.. .. 0.68... . 1.01
12 hr:*::: 3.23: 4.827.18::: 12 hr 0.27 0.40 0.60
24 hr *....... 3.70.... 5.56.... 8.30 ............... .24 hr 0.15.. .. 0.23... . 0.35..............
From Eqs. 111-(1-3), p.lll-(4-5), Stormwater Management: Vol.] Intensity Depth (Time
Urban Hydrology. B.H.Bradford, N.S.Grigg. L.S. Tucker
::.Tc 5.00 min
3. 10-Year Discharge Rate, 010 = C`ilo*A, cis
C= Weighted rational coefficient
110 = Rainfall intensity associated with l0-year storm, in/hour
A = Drainage area, fts
C= 0.402
0=7.22 : in/hour::
A= 1.11 acres
Q10 3.23 cfs::
Paget. DA4 :::
V. Bypass Channel Specifications
1, Calculated Depth of Flow using Normal-Depth Procedure
s:=: Channel slope = [Elev,uis-Elev.,,s]/L,: ft/ft
:Elevws Elevation at level spreader, ft
Elev.o;s Elevation at stream bank, ft
L:=: Length of channel from level: spreader to stream, ft:::
Elev.uis = 178.1 ft
Elev.ois = : 176.7 ft
............................................
L=..54.92..fit
a = 0.0255 ft/ft
2. Bypass Channel Dimensions: (for trapezoidal channel}
a) :Cross-sectional Area, Ax = QmA<a, ft2
Q,q = 10-year design flow, cfs
Va :=:Chosen : to be less than the maximum allowable channel velocity,: 5 fps for tne:10-yr event according to the NC Erosion &
Sediment Control: Planning and Design: Manual: tattle 8.05a for a Bermudagrass: lined channel
Qm= .3.23. cfs
Va= 3.1. fps.:::
Ax 1.04. fti
b) working constant,. w, = M - 2`,,t1+M2]
M = Side slope ratio (H:V)
M= 3H:1V:::
w, -3.32.: (will: always be negative)
c) working constant,: w2 = Ax([[(Va*n)/(1.49,,9)]3'2]
Ax = Channel cross-sectional. area, ft2
Va =:Chosen : to be less than the maximum allowable velocity
n:=: Manning's:roughness coefficient [0:030 for grass-lined; 0.033: for riprap-lined (Applied: Hydrology by Chow, Table 2.5.1, pp. 35)]::::
s.=: Channel slope, ft/ft
Ax= 1.04: fti
Va = : 3.1 : fps
n = 0.030
a = 0.0255 ft/ft
w2 ...4.26
d) Depth: of Flow, d = [-w2 + (w27+4w,Ax)]/2w„ ft
w, =Working constant
w2=Working constant
Ax =Channel cross-sectional area. fti
w,=...-3.32
w2= ..4.26
k= .1.04 ft
: d= 0.329 ft
e) Bottom Width of Channel; B = A,/d - M*d, ft.:
Ax.=:Channel cross-sectional area, fti
d = Depth of flow, ft
:M = Side slope ratio (H:V)
Ax = 1.04 fti
d= 0.329 ft
M= 3H:1V::
B=...2.19..ft ..............................................................................
Page 3 DA 4
f) Top width of channel t = B+(2*d'M), ft
B = Bottom width of channel, ft
d = Depth of flow, ft :14 t
M = Side slope ratio (H:V) :=M
B= 2.19 ft ::d- 0.329 It
M=.......3H:1V ............................ .........................
t=...4.16 ft.:... g
3. Velocity Check:::
a): Wetted Perimeter, P = B+2dy[M2+1] ft
B = Bottom width of channel, ft
d=Depth offlow, ft .................................................................................
M = Side slope ratio (H. V)
B=...2.19 ft.::::
d= 0.329 ft.::::
M_ 3H:1V.:
P= 4.26 ft
b) Hydraulic Radius. R = A/P
:A, = Channel cross-sectional area, ftz
:P = Wetted Perimeter, ft
A, 1.04 ft2
P 4.26 ft.....
R 0,244 ft
c) Bypass Channel Velocity, v = (1.49/n)`R"S" fps
--velocity must be less than 5fps according to E&S Control Planning and Design Manual - Grass-Lined Channels
n = Manning's: roughness coefficient [0.030 for grass-lined: 0.033 for riprap-lined (Applied Hydrology by Chow, lab/e 2.5.1, pp. 35)]
::::
R = Hydraulic radius, wetted cross-sectional area (A) / wetted pereimeter (P), ft::::
s= Channel slope,.ft/ft
n= 0:030
R=...0.244..ft ..............................................................................
a= 0.025 ft/ft.:::
V=3.10 fps::
Check: Velocity is within allowable maximum velocity for Bermuciagrass: lining. Atemporary lining of erosion control
matting will be used for stabilization until grass is established.
For this depth, the resulting shear stress is then:
Shear Stress, T = yds lb/ftz
y = Unit weight of water, 62.4 Ib/ftz
d=. Flow depth, ft.:
s:= Channel: gradient, ft/ft.::::
y = 62.40 Iblfta
d=....:0.33 ft ...........................................................................
s = 0.025 : ftlft
T= 4.5: Ib/ft':
This shear stress is under the permissible unit shear stress (2 lb/ft2) for synthetic mat (erosion control matting) as stated in the NC
Erosion & Sediment Control Planning and Design Manual, Table 8,05g:
VI. Flow Splitter (Forebay) Specifications
Using the orifice equation, Q= Cd=A•(2,g:h)(112)
a) Pipe Cross-sectional Area, AP;re = [n/4]d2, ft'
d = Diameter of pipe from forebay to flow splitter, in d - 4 inches.:
::: A,j, F: 0.0872 ft2
Page 4 DA 4
b) Head Above Bypass Pipe, h:=:[(Q/(Cd*A)ft2*9, ft
(solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
Q = Discharge, cfs (1 inihr discharge)
Cd Discharge coefficient (0.6 for sharp-edged critical
Apipe: Pipe cross-sectional area, ft::::
g= Gravitational acceleration, ft/s2
h:=: Height of water: above: the orifice (head), ft
Q= 0.45 cfs
Cd= 0.6:
AVi, = 0.0872 ft°
9 = 32.2 ftis2 :. .
h= .:1.13: ft.....
VII. Swale Drainage Calculations
The following calculations use Darcy's law to calculate the time (in hours) that it will take for the Swale
upslope of the /eve/ spreader to naturally drain based: on the permeability of the in-situ soils.::::
a) Surface Area Draining to In-Situ Soil, A = L*W, ft2
L Level spreader length: ft
W = Width of swale upslope of level spreader, ft
L=29.08 ft.::::
W - 3: ft.::::
A.=.. 87.23..ft.....
b) Groundwater Flow, Q = (K*i*A)/43200 cfs Darcy's Law
K = Average coefficient of permeablilty, in/hr[4 in/hr based on Wehadkee Loam soils from 0 to pinches in depth]
based: on the Johnston County: Soil Survey (NRCS).::::
i = Hydraulic: gradient [assumed to equal 1]
A = Surface area draining to in-situ soil, tf2
K = :4 : in/hr
f_....1 ...................................................................................
A = 87.23 ftv.::::
Q = 0.0081 cfs
c) Volume Draining to In-Situ Soil, V = d*A, ft2
d:=: Depth of water draining: to in-situ soil, in::
A = Surface area draining to in-situ soil, ft
d :6 in
A=87.23 ft2.....
V=43.61 ft'
d) Time to Drain the Swale = V/Q, sec
V = Volume drained. ft3
Q = Groundwater: flow, cfs
V = 43.61 fts.::::
Q = 0.0081 cfs
Td=...5400 s.::::
::::.::....Td=... 1.50.. hr.....
Check: Since the water held in the swale after the level spreader has been activated will naturally drain In less than 24
:hours, no underdrain will tie: necessary.:::
Pages. DA4 :::
Level Spreader Design Spreadsheet

.................................................
DA 05
...........................................
Taft Woods
S&EC Project No. 9197.D1
I. Determine Contributing Impervious Area and:1ln/hour: Discharge Rate
1. Weighted Rational Coefficient, C = S[C;*%oA;]
C = Rational coefficient for development area
:A:=Area
Total Drainage Area 0.93 acres
Development Area (it 2) Area (ac.) % Area Rational C % Area * C
Lots -:Impervious (roof, parking. etc.) 1241.80 0.029. 3.1% 0.95. 0.029
..............Lots -Forested 0.00 0.000 0.0% 0.15... ..0.000
Lots -Lawn (maintained grass) 9419.37 0.216 23.2% 0.2 0.046
Impervious (Roads) 13091.83 0.301 32.3%a.... 0.95 0.307
Road: Easements (maintained: grass) .16769.03: 0.38541.4%:: : 0.2 0.083
total: 40522.04 0.930 .................. .. 0.465
weighted rational coefficient, C =...0.465..
impervious drainage area = 14333.64 ft2
total drainage: area 40522.04 ft2
2. Discharge Rate. Q = C*i*A, cfs::
Rational Equation, Applied: Hydrology by Chow, pp.:497:::
C=Weighted rational coefficient:
i= Rainfall intensity.
A = Drainage area, ft2
C = 0.465:
I=...1.00 in/hour ................................ ...........................................
A = 0.93 acres
Q = .: 0.43 cfs
II. Sizing the Forebay
Forebay Area., Alr6, = 0.2%o(Av ,.), ftv
Ai, r. = Contributing impervious area, ft?
Amp.= 14333.64 $2
kllbay 28.67. ft2
Ill. Determine Level. Spreader Length & Slope. Check
**Choose one of the following,: a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick. ground cover vegetation '--13 feet of level spreaderper 1 cis of flow
b: Forested with little/no ground cover. vegetation and 50-foot vegetated buffer '--65 feet of level spreader per 1 cis of flow
c: Forested with little/no ground cover vegetation and 100-foot vegetated buffer '--50 feet of level spreader per 1 cis of flow
d Forested with little/no ground cover vegetation and 150-foot vegetated buffer '--40 feet of level spreader per l cis of flow
Cover: b (a b, c, or d from above)
Total discharge, Q = 0.43 cfs
Length of level spreader =... 28.13. ft
Check: Lever spreader Is within allowable length requirements of greater than 13 feet and less than 130 feet.
Page 1.: DA 5: ::::
s = Slope of ground downslope of level spreader = [Elev.urs-Elev.Djs]/L, tuft
EIBV.uB = Elevation at level spreader, ft.::
Elev.01s = Elevation at stream bank (or at the edge of a 50' vegetated buffer or filter strip), it
L = Length from level spreader to stream (or edge of 50' buffer or filter strip), ft
Elev.u,= : 189.22 ft
Elev.ors= 185.91 ft::::
L=76.91 ft....
s= 0:0430 ftlft
Check: Slope is less than 6%..::::
IV. Determine Bypass Channel Design Flow (Riprap Lined or Grass Swale)
I . Time of Concentration, T.=:0.0078*Lo.77S-oa8s min
Kirpich Equation, Applied Hydrology by Chow, pp. 500::
L = Flow :length . from headwater to outlet (ft)
H= Elevation difference from headwater to outlet (ft)
S = Average slope = H/L{ft/ft)
L=...637.9 ft.:::
H=...38.0 ft.:::
S=0.060 ft/ft
To=...3.34 min::
2.: 10-Year Storm Intensity,: i,o based on :Intensity-Duration-Frequency (IDF) Table
i,: = 10-year intensity that occurs: at the time of concentration, T,
TABLEI.:INPUT
Location: Taft Woods East
Duration:..... 2yr 100 yr Source
(in) (in)
5 min 0.48 0.81 NOAA: Hydro 35
15 min:. 1.03 1.88:. NOAA Hydro 35 ::........ .......... ......... ........ ............... .
60 min.. ...1.83 3.80 NOAA Hydro 35
24 fir: 3.70 : 8.30:. USWB TP 40
TABLE 2. DEPTH - DURATION - FREQUENCY TABLE 3. INTENSITY -DURATION- FREQUENCY
Duration 2: yr 10 yr: 100 yr 2yr 10 yr 100 yr
H-1.*: (in) (in) (in) Duration (in/hr) (in/hr) (in/hr)
5 mint 0:48.... 0:60.... 0.81 ............... ..5 min..... ... 5.80... . 7.22.... 9.68............ .
10 min 0.81 1.05 1.44 10 min 4.83 6.28 8.64
15 min*: 1.03 .::1.36: 1.88:: 15 min 4.12 542 7.52.::::
30 min.. ..::1.42 .::1.97: : 2.82:: 30 min 2.84 3.94 5.64
60 min:*: .....1.83.... 2.61.... 3.80 ............... .60 min..... . 1.83:.. . 2.61:..: 3.80:........... .
2 hr. * 2.04 2.94: 4.30.: 2 hr 1.02... 1.47.... 2.15.::::
3 hr: * 2.24 : 3.26: 4.79:: 3 hr 0.75 1.09 1.60.::::
6 hr * 2.77.... 4.09.... 6.05 ............... ..6 hr 0.46... . 0.68.... 1.01............ .
12 hr:.: 3.23 4.82 7.18.: 12 hr 0.27... 0.40.... 0.60.::::
24 hr: * 3.70 5.56: 8.30 24 hr 0.15... 0.23.... 0.35.::::
From Eqs.: 111-(1-3), p.lll-(4-5),: Stormwater Management: Vol.] Intensity = Depth / Time
Urban Hydrology. B.H.Bradford, N.S.Grigg L.S. Tucker
T?=.. 5.00 min
3. 10-Year Discharge Rate, Q?o:= C*i,o*A, cfs
CWeighted rational coefficient
i,: = Rainfall intensity associated with 10-year storm,: in/hour
: ADrainage area, ft2
C=...0.465
qQ= 7.22 in/hour
-A= ... 0.93 acres
Qto= 3.13 cfs...
..:Paget DA5
V. Bypass: Channel: Specifications:
1. Calculated Depth of Flow using Normal-Depth Procedure
s = Channel slope = JElev.ujs-Elev.njs]/L, ft/ft.:
Elev.ujs = Elevation at level spreader, ft
.::::
Elev.ujs = Elevation at stream bank, ft
L = Length of channel from level spreader to stream, ft.
:Elev.ujs = ..190.4. ft
Elev:ms = 185.77 ft
L=123.16 ft
s = 0.0376 ft/ft
2. Bypass Channel Dimensions (for trapezoidal channel)
a) Cross-sectional Area, A. = DjoNe, ft2
Dio =.10-year design flow. cfs
Ve = Chosen to be less than the maximum allowable channel velocity, 5 fps for the 10-yr event according to the NC Erosion &
Sediment Control Planning and Design Manual table 8.05a for aBermudagrass lined channel
CIO= 3.13 cfs.
V. = 3.5: fps
A. 0.89:
1112
b) Working Constant, w, = M - 2*41:+M2]
M =Side slope ratio (H.V)
M= 3 H:1V
Wl = 3.32:. (will always be negative)
c) Working Constant; w2 = A,/[[(V,*n)/(1.49vs)]@nl
A,= Channel cross-sectional area, ft2
Va = Chosen to. be less than the maximum allowable velocity
n = Manning's roughness coefficient [0.030 for grass lined; 0.033 for riprap lined(Applied Hydrology by Chow,: Table 2.5.1, pp. 35)]
s = Channel slope, Rift
:.A.= 0.89. ft2
Va= 3.5 fps.::::
n= 0.030:
s=.:0.0376 ft/ft.
w2 ..4.08:
d) Depth of Flow, d:=.[-w2+4w22+4w,A,)]/2w,. ft:
w,:= Working: constant
w2= Working constant
A,= Channel cross-sectional area, ft2
w,= -3.32:
w2= ..4.08:
A, = : 0.89 ft2
...............................................................................
:. d=...0.286. ft
e) Bottom Width of Channel, B.=.A,/d-.M'd,ft
A,= Channel cross-sectional area, ft2
d Depth of flow, it
M =Side slope ratio (H:V)
A, 0.89. ft2
d= 0.286. it M 3 HAV
B=...2.27..ft ...............................................................................
Page 3.: :DA.5
:f) Top Width of Channel, t B+(2'd`M) ft:::
B Bottom width of channel, .........................................................................
d = Depth of flow, ft t
M:=: Side slope: ratio (H:V)
B= 2.27 It d ?.1..
:..
d= 0.286 ft
M 3:H:1V: M:::
t=...3.98..ft ............................. ?A g?................................
3. Velocity Check::
a) Wetted Perimeter, P = B+2d4M2+11, ft:::
B:=:Bottom width of channel, ft
d =:Depth of flow, ft
...........................................................................
M= Side slope ratio (H:V)
B= 2.27 ft
d.=...0.286..ft .............................................................................
M=..... 3H:1:V:
P=...4.08.. ft..
b) Hydraulic Radius, R=A/P..
A„ = Channel cross-sectional area, ftz
P= Wetted Perimeter, ft.
A.= 0.89 ftz...
P=...4.08 ft.:::
R =... 0.21.9.. ft
c) Bypass Channel Velocity, v (1.49/n)'R"Svz fps
`--velocity must be less than 5 fps according to E&S Control Planning and Design Manual - Grass-Lined Channels
n = Manning's roughness coefficient 10.030 for grass-lined; 0.033 for riprap-lined (Applied Hydrology by Chow, Table 2.5.1, pp. 35)}
R:=:Hydraulic radius, wetted: cross-sectional area (A) /:wetted pereimeter (P), ft
s = Channel slope, ft/ft
n=...0.030
R:=0.219 ft::::
s=...0.038ft/ft
V=...3.50 fps:.
Check Velocity is within: allowable maximum velocity for Bermudagrass lining. A temporary lining of erosion: control
matting will be used for stabilization until grass is established;
For this depth, the resulting shear stress is then:
Shear Stress T := yds, Ib/ftz::
y Unit weight of water, 62.4 lb/ft'
d= Flow depth, :ft.
s=Channel gradient, ft/ft :...........................................................................
y = .:62.40 Ib/ft'
..........................................................................
d=.....0.29.....it
s- ...0.038 ft/ft
:::..T=......0.7 Ib/ftz
This shear stress is under the permissible unit shear: stress (2 Ib/ftz) for synthetic mat (erosion control. matting) as stated in the NC
Erasion & Sediment. Control Planning and Design Manual, Tattle 8.05g
Vl: Flow Splitter (Forebay) Specifications
Using the orifice equation. Q = Ca•A•(2•g•h)(112)
a) Pipe Cross-sectional Area, A,I,, fn/4]d2:, ftz
d = Diameter of pipe from forebay to flow spldter, in
d 4 inches:
A,ip = 0.0872 ft2
:Page4 DA5 :::::
b) Head Above Bypass Pipe, h= [(Q/(Cd*A))2]12`g ft
(solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
:QDischarge, :cfs:(1 in/hr discharge)
Cd:=. Discharge coefficient [0.6 for sharp-edged orifice]::::
Apipe = Pipe cross-sectional area, ftP
g = Gravitational acceleration, ftls?
h = Height of water above the orifice (head), ft:
Q= 0.43 cfs.::::
Cd= 0:6::
APIPa 0.0872 ft
q= ..32.2 Posz::::
h=... 1.06.. ft......
VII. Swale Drainage Calculations.:
The following calculations use Darcy's law to calculate the time (in hours) that it will take for the Swale
upslope of the level spreader to naturally drain: based on the permeability of. the in-situ soils..::::
a) Surface Area Draining to In-Situ Soil, A =. L*W., ft2
L = Level spreader length, ft ............................................................................
W:=: Width. of swale upslope of level spreader, ft
L= 28.13. ft
W = 3.. ft
A= 84.40. W.::::
b) Groundwater Flow:, Q (K*I*A)/43200 cfs Darcy's Law:
K = Average coefficient of permeability, in/hr [4 in/hrbased on Pacolet Loam soils from 0 to 8 inches in depths
based on the Johnston County Soil Survey (NRCS)
i = Hydraulic gradient [assumed. to equal 1]
:::
A= Surface area draining to in-situsoil, ft2
K = 4 in/hr
A = 84.40. ft'
4= 0.0078 cfs.:...
c) Volume Draining to In-Situ Soil, V = d*A, ft2
d = Depth of water draining to in-situ soil, in
A = Surface area draining toxin-situ soil, ft::::
d= 6in
:A= .:84.40. ft'.....
V=.::42.20. ft'
d) Time to Drain the Swale = V/Q. sec
V = Volume drained, ft3
Q= Groundwater flow, cfs
V= 42.20. ft`.::::
Q = 0.0078 cfs
Td= 5400. s
:::::..... Td=... 1.50.. hr
Check: Since the water held in the swale after the level spreader has been activated will naturally drain In less than 24
hours, no:underdrain will be necessary.::::
Page 5:: DA 5
: :::
Level Spreader Design Spreadsheet
DA:#6.
Taft Woods
S&EC:Project No. 9197.D1
1. Determine Contributing Impervious Area and Iin/hour Discharge Rate
1. Weighted Rational Coefficient, C = E]C*%A;]:
C = Rational coefficient for development area
A =Area
.:Total Drainage Area : 1.62 acres
Development Area (it') Area (ac.) % Area Rational C % Area * C
Lots-Impervious (roof, parking, etc. 1128.87 0.026 1.6% 0.95 0.015
Lots- Forested 0.000..0000.0% 0.15 0.000:::
Lots - Lawn (maintained grass) : 7995.63 0.184 11.3% 0.2 0.023
Impervious (Roads) 25334.48 0.582 35.9% 0.95 0.341
Road Easements (maintained grass) 36199.08 0.831 51,2% 0.2 0.102
total::. 70658.06: 1..622::: 0.481::::
::::... weighted rational coefficient, C= 0.481.:
impervious: drainage area26463.35 ft2
total drainage area =:.... 70658.06. ft2
2. Discharge Rate, Q CYA, cfs
Rational Equation, Applied Hydrology by Chow, pp. 497
:.C = Weighted: rational coefficient
i= Rainfall: intensity
A = Drainage area, ft2
C .0.481
i = .::1.00 in/hour::
A=...1.62acres
.................................
::::.::.... Q=... 0.78 cis....
II. Sizing the Forebay:
Forebay Area, Atorahay 0.2%(A;m,) ft
A;mp.= Contributing impervious area, ft?
A;mp = 26463.35 ftz
Aforenay =: 52.93 ft2.... :.....
III. Determine Level Spreader Length & Slope Check
**Choose one of the following,. a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation `--13 feet of /eve/ spreader per 1 cis of flow
b: Forested with little/no ground cover: vegetation and 50-foot vegetated buffer::: : :. '--65 feet of level spreader per 9 cis of flow
c: forested with little/no ground cover. vegetation and 900-foot vegetated buffer '--50 feet of level spreader per 1 cis of flow
d: Forested with little/no ground cover vegetation and 150-foot vegetated buffer '--40 feet of level spreader per 1 cis of flow
.:Cover; b : (a, b,: c, or d from above)
Total discharge, Q= 0.78 cfs.::::
Length of level spreader = 50.70 ft
Check: Lever spreader is within allowable length requirements of greater than 13 feet and less than 130 feet.
Pagel. DA6 :::
s.= Slope of ground downslope of level spreader = [Elev.ujs-Elev.o18]/L, Wit
:Elev:ws =. Elevation at level: spreader, ft
Elev.pjs.=. Elevation at stream bank .(or: at the edge of a: 50' vegetated buffer or filter strip), ft
L = Length: from level spreader to stream (or edge of 50' buffer or filter strip), ft
Elev.ois = 193.53 ft
Elev.ois : 186,96 ft

.................................
L=111.49..it
..........
........
........
...................
s=0.0589 ft/ft.:..
.:Check: Slope is less than 6%.
IV. Determine Bypass Channel Design Flow (Riprap Lined or Grass Swale)
1. Time of Concentration, T, = 0:0078*Lo.riS"" min
:Kirpich Equation, Applied Hydrology by Chow, pp. 500:::
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (ft)
S= Average: slope =:H/L(ft/ft)::
L= 1197.4 ft.::::
H 67.0 ft.::::
S ...:0,056 ft/ft::
T°=...5.55 min
2. 10-Year Storm Intensity. i1o based on Intensity-Duration-Frequency (IDF) Table
{o =.10-year. intensity that occurs at the time of concentration, T,;
TABLE 1.INPUT
. .Location. :Taft Woods East.::
Duration: 2 yr : .:100 yr Source

.......................
(in) (in)
..........
........
........
...................
5min 0.48 0.81 NOAA Hydro 35
15 min::: 1.03: 1.88NOAA Hydro 35
60 min::: : 1.83 3.80 NOAA Hydro 35
24 hr.... 3.70 830 USWB TP 44
TABLE 2. DEPTH:- DURATION -. FREQUENCY TABLE 3.:INTENSITY : - DURATION -: FREQUENCY
Duration 2 yr : 10 yr:: .100 yr 2 yr 10 yr 100 yr
H-1 *:. (in) :.(in) (in) : Duration (in/hr).. . (in/hr).. (in/hr)
5min * 0.48: 0.60 0.81 5min 5.80 7.22 9.68
10. min0.81: .:1.05144::: 10. min 4.83 6.28 8.64
15 min * 1.03.... 1.36.... 1.88 15 min 4.12.. .. 5.42... . 7.52 ..............
30 min 1.42: 1.97 2.82.:: 30 min 2.84 3.94 5.64
60. min:*:: 1.83: 2.613.80::: 60. min 1.83 2.61 3.80
2. hr *....... 2.04.... 2.94.... 4.30 ............... . 2. hr 1.02.. .. 1.47... . 2.15..............
3 hr:* 2.24: 3.26 4.79.:: 3.hr 0.75 1.09... . 1.60
6 hr * 2.77 4.09 6.05.:: 6. hr 0.46.. .. 0.68... . 1.01
12 hr:*::: 3.23: 4.827.1$::: 12 hr 0.27 0.40 0.60
24 hr *....... 3.70.... 5.56.... 8.30 24 hr 0.15.. .. 0.23... . 0.35 ..............
From Eqs. 111-(1-3), p.Ill-(4-5), Stormwater Management: Volt Intensity= Depth / Time
Urban Hydrology. B.H.Bradford, N.S.Grigg, L.S. Tucker
::.Tc = 5.55 min
3. 10.-Year Discharge Rate, .Qio=C*ilo*A, cfs.:

:......................
C= Weighted rational coefficient
..........
........
........
..................
iio= Rainfall intensity associated with 10-year storm,in/hour
A = Drainage area, ftz
C= 0881
110 =.::7.22 in/hour
:A=1.62 .acres::
Q10 5.63 cis....
Paget. DA6 :::
V. Bypass Channel Specifications
1. Calculated Depth of Flow using Normal-Depth Procedure:
s:=: Channel slope = (Elev.ws-Elev.ors]lL,: ft/ft
.:Elev.,, = Elevation: at level spreader, ft
:Eiev:o/s = Elevation at stream bank, ft
L= Length of channel from level spreader to stream, it
Elev.u, = : 193.5 ft
Elev.ois=. .:188. ft
L=94. ft
s=0.0585 ftlft .:...........................................................................
2. Bypass Channel Dimensions (for trapezoidal channel)
a) Cross-sectional Area, A. = QJON., ftz
Qio = 10-year design flow, cfs
V, Chosen to be less than the maximum allowable channel velocity, 5 fps for the10•yr event according to the NC Erosion &
Sediment Control: Planning and Design Manual: table 8.05a for a Bermudagrass: lined channel
Qio= 5.63: cfs
Va= 4.8. fps.:::
Ax = ..1.17 ftz
b) Working Constant, wi = M :2*vJl+M21
M = Side slope ratio (H:V)
:::
M 3 HIV
-3.32 : (will: always be negative)
c) Working Constant, w2 = Ax/[[(V3*n)/(1.49,,?)]3?2]
Ax =.Channel cross-sectional: area, ft2
Va:=: Chosen to be less than the maximum allowable velocity
n:=. Manning's: roughness coefficient [0.030 for grass-lined{ 0.033 for riprap-lined (Applied Hydrology by Chow, Table 2.5.1, pp. 35)]::::
s:=: Channel slope, ft/ft
Ax 1.17 ft2
Ve 4.8 fps::::
n=0:030
:............................................................................
s=0.0585ft/ft
w2=...4.65
d) Depth of Flow; d = [-w2 +'v w22+4wrAx)]/2wj, it wi Working constant
w2 Working constant
Ax=: Channel cross-sectional area, ft2
w, =...-3.32
w2= 4.65
A. 1.17 ft2
d .:0.331 ft.....
e). Bottom Width of Channel, B = Ax/d - M'd,:ft
Ax:=:Channel cross-sectional area, ftz
d = Depth of flow, it M = Side slope ratio (H:V)
Ax= 1.17 ft2
d= 0.331 ft
M= 3HAV::
B 2.56 ft
Page 3: :DA6 :::
f) Top Width of Channel, t = B+(2*d*M), ft
B = Bottom width of channel; ft
:d=Depth offlow, ft t.:
M = Side slope ratio (H:V)
B = 2.56 ft
d... 1
: d = 0.331 ft
M= 3H:1V.... M.::::
t=...4.54 ft ............................. fir.:- g -Ni:.................................
3. Velocity Check:::
a): Wetted Perimeter, P.=: B+2dVfM2+ll, ft
B = Bottom width: of channel, ft
d = Depth of flow, ft
M=Side slope ratio(H:V) .............................................................................
B= 2.56 ft
..............................................................................
d= 0.331 ft
M= 3H:1V.::
P-4.65 ft.....
b) Hydraulic Radius, R = A/P
A. Channel cross-sectional area, ft2
P = Wetted Perimeter, ft
A*= 1.17 ft?
P=...4.65 ft.....
:R 0.253 ft
c) Bypass Channel Velocity, v = (1..49/n)*R"Si/2,fps
--velocity must be less than 5 fps according to E&S Control Planning and Design Manual - Grass-Lined Channels
:n= Manning's: roughness: coefficient [0.030 for grass-lined; 0.033 for riprap-lined (Applied: Hydrology by Chow, Table 2.5.1, pp. 35)]::::
R = Hydraulic radius, wetted cross-sectional area (A) / wetted pereimeter (P), ft::::
s= Channel slope,.fUft
..............................................................................
n= 0.030 R= 0.253 ft
S= 0.059 ft/ft.
V=...4.80.. fps..
Check: Velocity Is within allowable maximum velocity for Bermudagrass: lining. Atemporary lining of erosion control
matting will be used for stabilization until grass is established.
For this depth, the resulting shear stress is then:
Shear Stress, T= y d s 1 b/ ft
y = Unit weight of water, 62.4 Ib/ft3
d= Flow depth, ft
s: = Channel: gradient, Wit
y = 62.40 Ib/ft3
d=....:0.33 ft ...........................................................................
S = 0.059 : fUft
:.T= 1,2: Ib/ft'.
This shear stress is under the permissible unit shear stress (2 lb/f?) for synthetic mat (erosion control matting) as stated in the NC
Erosion & Sediment Control Planning and Design Manual, Table 8.05g:
VI. Flow Splitter (Forebay) Specifications
Using the orifice equation, Q= Cd*A*(2*gxh)(p2) a) Pipe Cross-sectional Area, Apj, = [7/4]d2, ft2
d = Diameter of pipe from forebay to flow splitter, in
d= 4. .inches.:
Ap[, 0.0872 ft2
Page 4 DA 6 ::
b) Head Above Bypass Pipe, h = [(Q/(Cd*A))z]l2*g ft
(solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
Q = Discharge, cfs (1 in/hr discharge)
Cd = Discharge coefficient [0.6 for sharp-edged orifice]
Ap;pe Pipe cross-sectional area, ft
g Gravitational acceleration fUsz
h=height of water above the orifice (head), ft
Q = 0.78 cfs
Cd= 0.6:
Ap,, = 0.0872 ftz
g = 32,2 ft/sz....
h= 3,45. ft
VIL. Swale Drainage Calculations
The following calculations use Darcy's law to calculate the time (in hours) that it will take for the swale
upslopeof the level spreader to naturally drain based on the permeability of the in-situ soils.
a) Surface Area Draining to In-Situ Soil, A= L*W, ftz
L:=: Level spreader length, It W = Width of swale upslope of level spreader, it L = 50.70 ft
..............................................................................
W._....3....ft
A = 152.11 ftz.:...
b) Groundwater Flow, Q=(K*i*A)/43200,cfs Darcy's Law
K = Average coefficient of permeability, in/hr.[4 in/hr based on Pacolet Loam soils from 0 to 8:inches in depth]
based on the Johnston County Soil Survey (NRCS)
= Hydraulic gradient [assumed to equal 11
A = Surface area draining to in-situ soil:, ft`.::
K= 4 in/hr.::
i 1..
A 152.11 ftz.....
:Q 0.0141 cis
c) Volume Draining to In Situ Soil, V d*A, ftz
d= Depth of water draining to in-situ soil, in
A = Surface area draining: to in-situ soil. It d= 6. in.
A= 152.11 ftz.::::
V 76.06. ft3.....
d) Time to Drain the Swale = V/Q, sec
V = Volume drained, ft'
Q = Groundwater flow, cfs
V = 76.06 ft3
Q=0.0141 cfs::::
Td= 5400 S
Td= 1.50 hr
Check: Since the water held in the Swale after the level spreader has been activated will naturally drain in less than 24
hours, no underdrain will be necessary..::
Page 5: DA6 :::
Level Spreader Design Spreadsheet
DA:#7.
Taft Woods
S&EC:Project No. 9197.D1
1. Determine Contributing Impervious Area and linihour Discharge Rate
1. Weighted Rational Coefficient,: C = F[Ci*%A;]
.
Q= Rational coefficient for development area
A =Area
Total Drainage Area = 2.80 acres
Development Area (ftz) Area (ac.) %Area RationalC %Area *C
Lots-.Impervious (roof, parking, etc.) 8103.61 0.186 6.6% 0.95 0.063
Lots- Forested .1285.00: 0..0291.1% 0.15 0.002:::
Lots - Lawn (maintained grass) : 47433.05 1.089 38.9% 0.2 0.078
Impervious (Roads) 23541.84 0.540 19.3% 0.95 0.183
Road Easements (maintained grass) 41531,08 0.953 34.1% 0.2 0.068
total:: 121894.6: 2.798::: 0.394:::
weighted rational coefficient, C= 0.394.:
impervious: drainage area 31645.45 ft2
total drainage area =.... 121894.6. ft
2. Discharge Rate, Q= C*i*A, cfs
Rational Equation, Applied Hydrology by Chow, pp. 497
:.C = Weighted rational coefficient
:i p Rainfall intensity
A = Drainage area, :ft
C 0.394
1_... 1.00 in/hour ................................ ..........................................
A = ...2.80 acres
::::.::.... Q=...1.10 cfs....
it. Sizing the Forebay:
Forebay Area , Ato,ebay = 0.2%(A;m,) ft2
Aim, = Contributing impervious area, ft'
Amp. = 31645.45 ft2
Afor , =: 63.29 ft2 :.....
III. Determine Level Spreader Length & Slope Check
**Choose one. of the following,: a-d
Level Spreader Design Guidance by DWQ
a: Grass or thick ground cover vegetation '--13 feet of level spreader per 9 cfs: of flow:
b:: Forested with littlelno ground cover: vegetation and 50-foot vegetated buffer '--65 feet of level spreader per 1 cfs of flow
c: Forested with littlelno ground cover. vegetation and 1 00-foot vegetated buffer '--50 feet of level spreader per 1 cis of flow
d Forested with little/no ground cover vegetation and 150-foot vegetated buffer '--40 feet of level spreader per 1 cfs of flow
Cover: : b : (a, b,: c, or d from above)
Total discharger Q= 1.10 cfs.::::
Length of level spreader = 71.70: ft
Check: Lever spreader is within allowable length requirements of greater than 13 feet and less than 130 feet.
.::::...Page 1: DA?
s = Slope of ground downslope of level spreader = [Elev.us-Elev.ms]/L, ft/ft
:Elevuis = Elevation at level: spreader, ft
Elev.u s =. Elevation at stream bank (or at the edge of a.50'' vegetated buffer or filter strip), ft
L. = Length from . level spreader to stream (or edge of 50' buffer or filter strip), ft
Elev.us = 182.22
Elev.,s = 180.55
L=82.64 .................................... ......... ......... ........ ...................
:. .....s=0.0202
:Check: Slope is less than 6%.
IV. Determine Bypass Channel Design Flow (Riprap Lined. or Grass Swale)
1. Time of Concentration T. = 0.0078*L 1.77S-1,111, min
Kirpich Equation, Applied Hydrology by Chow, pp. 500:
L = Flow length from headwater to outlet (ft)
H = Elevation difference from headwater to outlet (ft)
:S= Average. slope s=.H/L(ft/ft)::
L=969.6 ft.::::
H=:. 59.0 ft.::::
S= 0.061..ft/ft ................................ ......... ......... ........ ...................
TO-...4.57 min:..
2. 10-Year Storm Intensity; 110 based on Intensity-Duration-Frequency (IDF) Table
i{o =90-year intensity that occurs at the time of concentration, T.
TABLE1:INPUT:
.: :Location: :Taft Woods East:::
:Duration: 2 yr : 100 yr:: Source

5 min 0.48: 0.81 NOAA Hydro 35
15 min 1.031.88 : NOAA Hydro 35
60 min::: : 1.83. 3.80 NOAH Hydro 35
24 1 ..3.70: 8.30 USWB TP 40 ........... ......... ......... ........ ...................
. :TABLE 2. DEPTH:- DURATION -: FREQUENCY TABLE 3. :INTENSITY - DURATION: -:FREQUENCY:
Duration... 2 yr 10: yr 100 yr 2 yr 10 yr 100 yr
H-1 * (in) (in) (in) Duration (in/hr) (in/hr) (in/hr)
5 min* : 0.48 0.60 : 0.81 5 min 5.80 7.22 9.68
10 min 0.81.... 1.05.... 1.44 10 min .... ....4.83.. .. 6.28... . 8.64 ..............
15min* .. 1.03: 1.36 1.88.:: 15 min 4.12 -5.42 ... .7.52
30 min... 1.42 1.97 2.82 30 min 2.84 3.94 5.64
60 min* 1.83 : 2.61 : 3.80 60: min 1.83 2.61 3.80
2. hr *....... 2.04.... 2.94.... 4.30 ............... . 2. hr 1.02.. .. 1.47... . 2.15..............
3 hr:*2.24: 3.26 4.79.:: 3.hr 0.75.. .. 1.09... . 1.60
6 hr * 2.77 4.09 6.05 6 hr 0.46 0.68 1.01
12 hr:*3.23: 4.827.18::: 12. hr 0.27 0.40 0.60
24 hr ........ 3.70.... 5.56.... 8.30 24 hr 0.15.. .. 0.23... . 0.35 ..............
From Eqs. p.lll-(4-5), Stormwater Management: VoLl Intensity= Depth /Time
Urban Hydrology. B.H.Bradford. N.S.Grigg. L.S. Tucker
T,- 5.00 min
3.
.:
10-Year Discharge Rate, 010 = C*iio*A, cis
C= Weighted rational coefficient
i1o= Rainfall intensity associated with l 0-year storm, in/hour
A = Drainage area, ftz
C= 0.394
i1q =7.22 in/hour
:A=2.80 acres
:.. Q10 7.97 cfs....
Page 2: DA7
V. Bypass Channel Specifications
1 . Calculated Depth: of Flow using Normal-Depth Procedure
s: Channel slope = IElev.ws-Elsv.?;s1/L,: ft/ft
:Elev.urs = Elevation at level: spreader, ft
Elev.Djs =. Elevation at stream bank ft
:L:=. Length of channel from level: spreader. to stream, ft:::
Elev.urs 182.5 ft
Elev.ois 181: ft
L=65.02..ft ..............................................................................
a = 0.0231 ft/ft
2. Bypass Channel Dimensions: (for trapezoidal channel)
a) :Cross-sectional Area A. = QlOfVz, ft2
4,0 4 10-year design flow, cfs
V, =:Chosen : to be less than the maximum allowable channel velocity,: 5 fps for the:10-yr event according to the NC: Erosion: &
Sediment Control: Planning and Design Manual table 8.05a for a Bermudagrass: lined channel:::
Qm = 7.97 cfs
`r = 3.7: fps
Ax=...2.15 ft2.::::
b) Working Constant, w, = M - 2*vf1+M21
M= Side slope ratio (H : V)
M 3H.1V:::
w" 3.32 (will. always be negative)
c) Working Constant, w2 = Ax/[I(V,*n)/(1.49i,9)13Ml
Ax =:Channel cross-sectional. area ft2
V, :Chosen to be less than the maAmum allowable velocity
n = Manning's: roughness coefficient [0.030 for grass lined; 0.033 for riprap-lined (Applied Hydrology by Chow, Table 2;5.1, pp. 35)
s.=. Channel slope, fUft
A.= 2.15 ft2
V. 3.7 fps
n = 0.030
a= 0.0231 ft/ft
w2=...6.27
d) Depth: of Flow, d I-%+4w22+4w,A.)]/2w,:, ft
w,:=: Working constant
w2 Working constant
Ax =Channel cross-sectional area, ft2.::::
W, =...-3.32
w2-...6.27
A. 2.15 ftz
d ...:0,452 ft
e) Bottom Width of Channel; B = Ax/d - M*d, it A. Channel cross-sectional area, ft2.::::
d=Depth of flow, ft M = Side slope ratio (H:V)
Ax= 2.15 ft2
d= 0.452 ft
M 3 H[1V::
B=...3.41..ft ..............................................................................
.::::...Page 3: DA7
f) Top Width of Channel, t =. B+(2.d.M), ft
B = Bottom width of channel, ft d:=. Depth of flow, ft
M = Side slope ratio (H V) 14 t ?'I::
B= 3.41 ft.::::
d= 0:452 ft d
::.....t.=... 6.12...ft..... M.::::
Im B ?I
3. Velocity Check
a) Wetted Perimeter, P =. B+2difM2+11, ft
B = Bottom width of channel, ft
d=Depth of flow, ft M= Side slope ratio (H:V)
B=...3.41. ft.::::
d= 0.452 R.::::
M= 3H1V::
P=...6.27..ft ..............................................................................
b) Hydraulic Radius. R = A/P
k =:Channel cross-sectional: area, ft2.::::
:P = Wetted Perimeter, ft
A, - 2.15 ft2
P6.27 ft.....
:. R= 0.343 ft ..............................................................................
c) Bypass Channel Velocity, v = (1:49/n)•RM'Su2 fps
'--velocity must be less than 5 fps according to E&S Control Planning and Design Manual Grass-Lined Channels
n= Manning's:roughness coefficient [0.030 for grass-lined; 0.033 for riprap-lined (Applied: Hydrology by Chow, Table 2.5..1, pp. 35)]
::::
R = Hydraulic radius; wetted cross-sectional area (A) / wetted pereimeter (P), ft
:s= Channel slope, ft/ft
n- 0.030
R= 0.343 ft.::::
s=0.023 ft/ft
V = .::3.70 fps
Check: Velocity is within allowable maximum velocity forBermudagrass lining. 'A temporary lining of erosion control
matting will be used for stabilization until grass is established.
For this depth, the resulting shear stress is then.
Shear Stress rT = Yds, Ib/ft?
:y.= Unit weight of water, 62.4 lb/ft3
d=: Flow depth:, ft
s:=. Channel gradient Wit
.::::
y= 62.40 Ib/ft3.
d= ...0.45 R.:
s = 0.023 : ft/ft:
T= 0.7: lb/ft':
This shear stress is under the permissible unit shear stress (2 lb/ft2) for synthetic mat (erosion control matting) as stated in the NC
Erosion :& Sediment Control Planning and Design Manual,: Table 8.05g.
VI. Flow Splitter (Forebay) Specifications
Using the orifice equation, 0:=: Cd'A*(2*g'h)(1/2) a). Pipe Cross-sectional Area, Apipe=[u/4]d2,. ft2.
d: = Diameter of pipe from forebay to flow splitter, in.::::
d= 4 inches.:
Apipe _ 0.0872 ft2....
Page 4: :.DA7
b) Head Above Bypass Pipe, In [(Q/(Cd`A))2]/2*g, it (solving for head above pipe that will be equal to the elevation of the bypass channel invert above the pipe to the level spreader)
Q = Discharge, cfs (1 in/hr discharge)
Cd = Discharge coefficient 10.6 for sharp-edged orifice]
Apip. =Pipe cross-sectional area, ft2
g = Gravitational acceleration, ft/s2
h Height of water above the orifice (head), it
Q= 1.10 cfs
Cd= 0.6
Apipe = 0.0872 ft`.::::
g= 322: fVs2....
h=...6.90. ft ..............................................................................
VII: Swale Drainage Calculations
The following calculations use Darcy's law to calculate the time (in hours) that it will take for the Swale
upslope of the /eve/ spreader to naturally drain based on the permeability of the in-situ soils.
a) Surface Area Draining to In-Situ Soil, A L*W, ft2
L = Level spreader length, ft
W = Width of swale upslope of level spreader, it
L 71.70 ft
W.=....3....ft ..............................................................................
:::: :..... A.=..215.09. ftz
b) Groundwater Flow, Q = (K*i*A)/43200 cis
Darcy's Law
K = Average coefficient of permeability, Whir [4 in/hr based on Pacolet Loam soils from o to 8 inches in depth]
based on the Johnston County Soil Survey (NRCS)
i Hydraulic gradient [assumed to equal 11
A:= Surface area draining to in-situ soil, ft2
K= 4.. in/hr.::
i 1::
A .::215.09 ft2.....
Q=0.0199 cfs .:...........................................................................
c) Volume Draining to In-Situ Soil, V = d*A, ft2
d= Depth of water draining to in-situ soil, in
A= Surface area draining: to in-situ soil, ft:::
d= 6. m.::::
A = 215.09 ft2.....
V=107.55 ft3
d) Time to Drain the Swale = V/Q, sec
V= Volume drained, fta
Q = Groundwater flow, cfs
V = 107.55 ft3
Q=0.0199..cfs .............................................................................
Td= 5400 s.::::
Td= 1.50 hr
Check: Since the water held In the swale after the level spreader has been activated will naturally drain in less than 24
hours, no underdrain will be necessary,
Page 5: :DA7 :::
SOIL & ENVIRONMENTAL CONSULTANTS; PA
ATTACHMENT II
NCDENR LEVEL SPREADER, FILTER STRIP, AND RESTORED RIPARIAN BUFFER
SUPPLEMENT WORKSHEETS

kTx
A
MCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION AP PLICATION FORM
LEVEL SPREADER, MITER "IP AND REST ORED RIPt"M aN BUFFER UtrPPLENIENT
This form must be filled out, printed and submitted
.... ....
ed hours :. kb' em e .........
I. PAOdEOT INFORMATION
Project name Taft Woods East
.
.. .
Contact name pa:acca Pefe-on
Phone number (919) 84,,-5900
....Date January 22, 202
Drainage area number
rl. DESIGN INFORMATION
For Level Spreaders Receiving Flow From aBLIP
Type of BMP.
Drawdown flow from the LIMP.: efs::
For Level Spreaders Receiving Flow from the Drainage Area
....Drainage area.: 218.518 ftz
.....Impervious surface area ............. ........ pS 59 ftz.
....Percent impervious 0.26
....Rational C coefficient 0 39:a
Peakilowfrom the l in/hrstorm 1.971477824 cfs
Time of concentration .. rain
....Rainfall intensity, 10-yr storm 7.22 in/hr
Peak flow from the l 0-yr storm 14.23406989 cfs
Where Does the Level Spreader Discharge?
To a bioretention cell? N (Y or N)
To a wetland? IN , (Y or N)
To a filter strip or riparian buffer? Y (Y or N) : v-
....Other (specify)::
Filter Strip or Riparian Buffer Characterization (if applicable)
....Width of grass.: 0. ft
....Width of dense ground cover 0 ft
....Width of wooded vegetation.:: 50 ft
....Total width :5G ft
Slope (from level lip to to top of bank) _ 4:75 %
.....Are any draws present?.:.:: N. (Y or N) :........... ................................
Level Spreader Design
Forebay surface area 1127 so ft
Feet of level lip needed per eta 65 ft/cfs
Answer W' to one of the following. :..
Length based on the 1 in/hr storm? `f (Y or N)
Length based on the 10-yr, 24-hr storm? N ; (Y or N)
Length based on the BMP discharge rate? N (Y or N)
..Design flow 1'.97 cis
Is a bypass device provided? " (Y or N)
::: Form SW401-Level Spreader,. Filter Strip, Restored Riparian Buffer-Rev 2::: Parts I. and II. Design Summary, page 1 o1`2'. :: :
.::Length of the level Ilin 1283 ft :: ... ,,.
Are level spreaders in series?:: Nil : (Y or N)
Bypass Channel Design (if applicable)
Does .the: bypass discharge through a:wetland? : N (Yor:N)
Does the:channel enter the stream at an angle? Y
Dimensions of the channel (see diagram below):
M 3 :ft
8 '"-'69 ft
W 10 34 :fl
y 0.292 ft
Peak: velocity in the channel: during the 10-yr,:24-hr storm 5 cfs::
Channel lining material bermudagrass; naldng
1 1
°---'--- --------*
M M.
D
:::. Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2.:: Parts L and 11. Design Summary,. page 2 of.2. :: :
&,._RIEQUIRED ITEMS CHECKLIST,
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information, This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No. s scale w i 0 nor e sen? 1 1 F} s 1 cw d«?d
a, l? cv is c3nC'_\ d,raw;n ?s .: ?tq SY ¢Q? is nc F
_ f 1lp 1. Plans (9=53 or a ger) of the entire site showing v „v \e , cam- s u??1e e F?\ s4 met av
Design at ultimate build-out bz r0wd?c
Off-site drainage (if applicable)
Delineated drainage basins(iridude-Rational-Ccoefficlent-penbasi)his aS ,r clvded in }v
-Forebay(ifapplicable), «kczche S c< lc?la 'anS,
- High flow bypass system,
- Maintenance access,
=x drainage easement and public right of way (ROW), and
- Boundaries of drainage easement.
__ fk tl? 2. Plan details ( -30-er4acge:) for the level spreader showing t 4 s scnl? aa? ,vl c\c c Lam^?t y'`y
- Forebay (if applicable), L? cr S ?:nc\c r? ce StruC1?<v
- High flow bypass system; dmwan js ??s sal r (s : c?
One foot topo lines between the level lip and top of stream bank; v s;b\e , ?paev zv?k 1
drainage easement, and S4 st ?cr Uva v?i3z,
(? p Design at ultimate build-out.
t S I l4 6-11.o 3. Section view of the level spreader (i1'=-2 LeHPrger) showing iDeN(,N'? \ qo?- { 0 5 . \? .
- Underdrain system (if applicable);
- Level lip;
- Upslope channel, and
Downslope filter fabric.
SJ\ J U Q. 1I 4. A-date stamped photograph of the filter strip that clearly shows the type of vegetation that is present
??. A rI c.}P_ S-Fr,..rn? ?5 r?oT orT +"C pMo-Fro , hc?,.?evC'r, ?i\ a 1r\G" S : :
taken cxc to i?1o9,. vo/Sa 10-4
5. An assurance that the installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
3 . 1 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized:
6-5 \ l 7. The supporting calculations.
_ fk4..a i3. A copy of the signed and notarized inspection and maintenance (10) agreement.
9. A copy of the deed restriction. k
Sc s C) Lt C_?rreu?}y nd CCn v CT U av v Co SSG oYti s?rv`i?n
?cr,' AAc R ' le.jt\ Syw''?c ?: GYS kA-T6 `=hhe.o;'
::: Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2 ::: Part III page 1 of 1: ::

MAL
WNW
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION AP PLICATION FORM
L W
E =1 UEI S1?F?? z R.
[I .R:S NIP A,%!D P"-ST
O?"ED rr, ?P' "1'N BiJF FM.i 'UF'PLEf,1EE[`P'
This form must be filled out, printed and submitted.
tho'Oii 4flwd 2..0Checkill (ir'wPi f coif ......d d Ski m e? aki . a/f oible o , .yed e :. , ddn?
[1, PROJECT INFORMATION
Project name TT. Wood? East
Contact name Rebacca Peterson
....Phone number:: (>•19) 846-5009
....Data January : 22, 2096
....Drainage area number DA eJ
1. 'iDESIGN INFORMATION
For Level Spreaders Receiving Flow From aBMP

.
Type of Mid

..
Drawdown flow from the BMP.: cis
.
For Level Spreaders Receiving Flow from the Drainage Area
....Drainage area.: 5303 e fts.:
Impervious surface area.:::: 14,314 ... fps
....Percent impervious 027 : (`L'i
....Rational C coefficient C...^.
Peak flow from the l 9n/hr storm: 0.492956841 cfs
....Time of concentration min
....Rainfall intensity, 10-yr storm 7,22 in/hr
Peak flow from the l 0-yr storm 3.559148393 cis
Where Does the Level Spreader Discharge?
To a Noretention cell? N :. (Y or N)
To a wetland? N (Y or N)
To a filter strip or riparian buffer? Y
.. . .... . .. .
(Y or N) T.,
..Other (specify)
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass.. it
.::Width of dense ground cover Cr it
Width of wooded vegetation... 50 it
.....Total width.... SD it
Slope (from level lip to to tap of bank) 5.98 %
..Are any draws presents N (Y or N)
Level Spreader Design
Forebay surface area 28:6 sgit
Feet of level lip needed per cis 65 fdcfs
Answer "Y" to one of the following
Length based on the 1 in/hr stormy Y (Y or N)
Length based on the 10-yr, 24-hr storm? .N (Y or N)
Length based on the RMPdischarge rate? N (Y or N)
Design flow O.49 cis
Is a bypass device provided? :Y (Y or N) "K
:: Farm SW401-Level Spreader, Fiiter Strip,. Restored Riparian Buffer Rev 2::: Parts I. and II. Design Summary, page 1 of 2. :: :
Length of the level lip ..32.05 ft Eet ; ra !. Il r y.'
....Are level spreaders in series?. N (Y or N)
....Bypass Channel Design (if applicable).
Does the bypass discharge through a wetland? N (Y or N)
Does the channel enter the stream at an angle? V
Dimensions of the channel (see diagram below):
M 3 ft
B 22; ft
Wc,21 fl
y o:922 ft
Peak velocity in the channel during the 10-yr, 24-hr storm 4.5 cis
Channel lining material . berr ddttgmss r marlin,
t v
------------- --------------
M M
8 m
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer Re,2 Parts I. and II. Design Summary, page2 of 2
Rt1JIREl}rITEN1S..HDKL(ST ... .. i
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No. ?- T is scare wr\l, na} rzr SCnch\ ({ c Sk«n c c
S 0. "e2 cte C??cr? dsci.w?nc,S . ?? -Fh?S SheR'r t5 ?lc?
-_ zl o 16 1. Plans ( 50 er Ia feF) of thes(entire site showing:
c? S U \e rn e t \ s1 ?E u vn
Design at ultimate build-out, e o? dzd
- Off site drainage (If applicable),
-Delineated drainage basins(inek,deRationalGcoefficientpenbasin), This tS ;ruadded i
- Forebay (if applicable),Fcch?d c is\a h ?nS.
- High flow bypass system;
- Maintenance access,
+i -Reecrded drainage easement and public right of way (ROVE, and
pp Boundaries of drainage easement.
IL_ t? file 2. Plan details (1" = 30' or larger) for the level spreader showing
- Forebey (if applicable),
High flow bypass system;
One foot topo lines between the level lip and top of stream bank
t- Reeerded drainage easement, and
- Design at ultimate build-out.
ti ! t c lh 3. Section view of the level spreader (1?- rfarger) showing. ?i+a ! vi,-'r Aro s> c<v\?
Underdrain system (if applicable),
- Level lip;
Upslope channel, and
Downslope filter fabric,
4. A-date-stamped photograph of the filter strip that clearly shows the type of vegetation that is present.
i'? no+ off. +Y V_ T_A
`v re T? zv, ? oraro?
ssurance fhaf the in stalled system will meet design specifications upon initial operation once the
5. An assurance`
O project is complete and the entire drainage area is stabilized
t J r 13e 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized:
W 7. The supporting calculations.
J k & A copy of the signed and notarized inspection and maintenance (I&M) agreement.
9. A copy of the deed restriction. A
S ?c- is ?o+ cvrre 4y dew ccs iCi c ?u Tcrv ??5 vc,?c? s??e vs Un
{e k4 2S? leue\ S?v e ?LVS Czn i p r 2 cu cC
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2 Part III, page 1 of 1

NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CE RTIFICATION AP PLICATION FORM
L EV I SPREADER, , FILTER Sit A IP €hiN REST ORED R11PAR11A ? BUFFz.R SUPPl ElA NT
This form must be filled out, printed and submitted.
hert1 ....P stbe ;:', s ao plit tall
L PROJECT INFORMATION
Project name Tag Woods Cast
.
.. .
....Contact name q dhe= Petersen
....Phone number:: 1919) A46.5900
....Date .,anuar{'?2 2008. ...
Drainage area number DA d3:.
L' DESIGN INFORMATION
For Level Spreaders Receiving Flow From aBMP
....Type of BMP. War 80^J
Drawdown flow from the BMP.: cfs::
For Level Spreaders Receiving Flow from the Drainage Area
, C' . ,
)z ' . rori, CSC'
Drainage area.: lid .. semi.,.,. •nr'„e -rn,'
Impervious surface area.:::: fts.. 'a r.,.(.,.ms> .'?.
Percent impervious r"I

:.....................
Rational Ccoefficient
.?r.°:,rj ,,.r., .r;.?"Ircsr,,;
Peak flow from the l In/hrstorm .. cfs .,^r;:
Time of concentration min
....Rainfall intensity, 10•yr storm. - in/hr .3` 11 5
Peakilow from the 10-yr storm cfs ,! I
....Where Does the Level Spreader Discharge?
To a bioretention cell? N (Y or N)
Toawetland?.: N (YorN)
To a filter strip or riparian buffer? Y (Y or N)
....Other (specify}
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass.: it
Width of dense ground cover 0 ft
Width of wooded vegetation::: 51 ft
.... Total width: 50 ft
Slope (from level lip to to top of bank) 4,62 %
.. Are any draws present? IN (Y or N)
Level Spreader Design
Forebay surface area sq ft:
Feet of level lip needed per cfs 65 R/cfs
Answer "Y" to one of the following.
Length based on the lin/hrstorm? .:::: N (Y or N)
Length based on the 10-yr, 24-hr storm? N (Y or N
Length based on the BNP discharge rate? Y (Y or N
Design flow _ 2 cfs
Is a bypass device provided?.. y (Y or N) Sf;
:: Form SW401-Level Spreader, Filter Strip,: Restored Riparian Buffer- Rev.2::: Parts I. and II. Design Summary, page 1 of 2: :: :
Length of the level llp 130 it :: :::: :::: '. •,I, -': :::: :::: ::::
Are level spreaders in series?.: N (Y or N)
Bypass Channel Design (if applicable)
Does the bypass discharge through a wetland? (Y or N)
Does the channel enter the stream at an angle?
.......................................................................................................
Dimensions of the channel (see diagram below):
M :ft:
g :fL:.
W f4::
y f4::
Peak velocity in the channel during the 1 0-yr, 24-hr storm cfs
Channel lining material
M..::
8.::
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2 Pans 1. and It Design Summary, page 2 af 2
tA, *3
Ill REWIRED. ITEMS CHECtCCIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification,
Page! Plan
Initi Is Sheet No. Z 7%? s scale wiU' lob r--?e_«scncbl?i Ft\- cn s «n i« d
3??2 ?onsl-YUCttcrn d?c?wtn?s. i`r -t?n?s Slne.e-F?'s n?-F
S LI cI to 1. Plans (*-58'-o-IargeK) of the entire site showing: v s v \e c s ? e M e z ?\ s4 ?? } cr?v
- Designatultimatebuild-out, be prc\J 6de
- Off-site drainage (if applicable),
- Delineated drainage basins (ineWe-Ratieeal GCOefficlent-per-basin), `his s r c\vde<? \ c -4 L
ereeav f f appfeable), kF«ch?5 c ?lC \ h ?S_
- Maintenance access, +"-:s cif z ?
t -s Regarded drainage easement and public right of way (ROVE, and
Boundaries of drainage easement.
2. Plan details (1 3t oHarger) for the level spreader showing:
?S c 0? \\
Forebay (if applicable), r i? 5 : iit?\'J a :>4 ;x?c e v
cc<i4Fucicn z <\?5,
_High flow bypass system,
One foot topo lines between the level lip and top of stream bank; ?'°' she tF i5 nc i vtS\ u
-A 'k? -Rceerded drainage easement and c>?p \e. nex i w\ vie ? cc en k z
-Design at ultimate build-out p nvid?c .
14 Ita 3. Section view of the level spreader (x-26-a-lamer) showing. i.)`kc i\ r)(A ?-t -Cc ke
Underdrain system (if applicable);
Level lip
Upslope channel and
- Downslope filter fabric.
2 S(' AW. IS. 4. A-date-stamped photograph of the filter strip that clearly shows the type of vegetation that is present.
A -io}'e-..S-?wv?? is no+ on +Me- p4?a}-o lno..,.;e?ler, e?11 pho-tOS
wZ?'V, ta. v1 cam 10 /'31 C9 cr vo/3110?
5. An assurance that the Installe system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
l 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
I-4 'DA"; .r drainage area is stabilized:
7CS n 1 5 g 5 U 7. The supporting calculations.
R S P FF 8. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
9. A copy of the deed restriction -k
S CG s ncr c rre?Ny ??de ccn rc?? 0 ?e?Forv co?Sucficr s?rvi? ?1
:. 'S'e'v! ?V ?.Q.SZ. te?.l e-k S7V Z.CLCSGVS ?YIC? '?h12\C- r'?>1aVY`1'o YlChA1C?:S.
his S penal rtes ve\ o4- -4ie SFor v watt plc ?.
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2 Part ill, page 1 of t ::: :

ATA t

MCDENR
STORMWATER MANAGEMENT P ERMIT APPLICATION FORM
401 CERTIFICATION AP PLICATION FORM
IH -P.-RL-XL`L. , FILTER STRIP AND REST ORED RiPMI`Y9AN BUFFER ISSUPPL M NT
This form must be filled out, printed and submitted.
T.?te . ilod Sam ch °st (Pad fll) raw be pM''tDd, Frlfed obf .... ...
J tPP ....w.....
L <PROJECT INFORMATION..
Project name ?. Taft Woods East
.. .
....Contact name.: Reriecea Peic°rsor.
....Phone number ,9191 &405900
....Date Janmry 22,2008
---
Drainage area number DA#4
H. DESIGN INFORMATION
For Level Spreaders Receiving Flow Froma UP
....Type of BMP.
Drawdown flow from the BMP.: efs::
For Level Spreaders Receiving Flow from the Drainage Area
Drainage area.: 48.413 ft,::
Impervious surface area 13;140 ft2
..Percent impervious 0.27
....Rational C coefficient 7.402
Peak flow from the 1 In/hr storm 0.446786639 efe
Time of concentration min
....Rainfall intensity, 10-yr storm 7.22 inlhr
Peak flow from the 10-yr storm 3.225799534 eta
Where Does the Level Spreader Discharge?
To a bioretention cell? N (Y or N)
To a wetland?.: N (Y or N)
To a filter strip or riparian buffer? Y (YorN) r ,a,r ;rr„., ., t., s°'O° ..r... °11, ?c' ^;.
....Other (specify)
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass:: C : ft
Width of dense ground cover C. it
Width of wooded vegetation: 5- ft
....Total width: 50 ft
....Slope (from level lip to to top of bank) 01
%
....Are any draws present?.:::: N (Y or N)
Level Spreader Design
Forebay surface area 26.3 sq it
Feet of level lip needed per cis 65 ft/cfs
Answer Y' to one of the fallowing.
Length based on the 1 in/hr storm? Y, (Y or N)
Length based on the 10-yr, 24-hr storm? N (Y or N)
Length based ontheBMPdischargerate? N (YorN)
....Design flow. 045.... ofs
Is a bypass device provided? Y (Y or N) r;!
::: Form SW401-Level Spreader,. Filter Strip, Restored Riparian Buffer Rev 2::: Parts I. and II. Design Summary, page 1 of 2:
.::Length of the level lip It ..
Are level: spreaders to series?:: N : (Y or N)
Bypass Channel Design (if applicable)
Does the bypass discharge through a wetland?: IN (Y or N)
Does the channel enter the stream at an angle?
Dimensions of the channel (see: diagram below):
M :ft
B 2.-9 : ft
W 4.te it y 0.329 : if Peak velocity in the channel: during the 10-yr, 24-hr storm f'3. i : cfs::
Channel lining material hermudavass ?? Inatii.ng
f 0________ _----------p
t
M :M:
------------------
Form SW401-Level Spreader, Filter Strip, Featured Riparian Buffer-Rev.2.:: Parts I. and 11. Design Summary, page of 2: :::
---------------------------
Please indicate the page or plan sheet numbers where the supporting documentation can be found An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No. -.Cole will not reclscv ably } Ck-) skcvnclc.?6
H 4 la 1. Plans (4-3OLor4arper-) of the entire site showm 9' c: a's ?P\e e ?
, ' s ??j mevrt?\ s?,?e4- ccvrl
- Designatultimatebuild-out, be Prov6AEd
- Off-site drainage (if applicable),
Delineated drainage Basins(ineG.ide-Rational-Geoefficient-peFbasin) -LVA s v- 0lcivdid ic? WI
_ Forebay (if applicable), «FF t ch S c ic?\ t c 5.
High flow bypass system.
- Maintenance access,
ke Reeerded drainage easement and public right of way (ROM and
Boundaries of drainage easement.
IRS I(p 2. Plan details (1" = W or larger) for the level spreader showing.
- Forebay (if applicable),
- High flow bypass system;
- One foot topo lines between the level lip and top of stream bank,
,f-* drainage easement and
nn - Design at ultimate build-out
?l _ I # ll2 3. Section view of the level spreader (d"- r) showing 'he'r tit0 rxA- k- sot -?9-
Underdrain system (if applicable),
- Level lip
- Upslope channel and
Downslope filter fabric.
AIA _E: 4. A-date-sfariftped photograph of the filter strip that clearly shows the type of vegetation that is present
.- R Ac??eis noz rn1: +Y,e P1?a-1-o v.? ever a\t phc S ::
10 5, An assurance that the Insl Ied syste will meet design specifications pon initial operation once the
project is complete and the entire drainage area is stabilized:
13 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
(} drainage area is stabilized:
L? ?1 1°5'DNi 7. The supporting calculations.
JLS rp PM- 8. A copy of the signed and notarized inspection and maintenance (Al agreement.
_ 9. A copy of the deed restriction. 1' S sec- 1s C) & C_ xr Aiy u?deY ccnaYC C? F? e?Form c nS{ruC\ c s" vCS or
?cV }4i i-Se 1e,?21 s'p??eaa ?x> end Th2?c ???vrh???ncu?c?LS.
h s s sera, c5 oval u? e- SFo?rnwc t?v plc n.
Form SW401-Level Spreader, Filter Strip Restored Riparian Buffer-Rev .2 Part ill page 1 of 1

HCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION AP PLICATION FORM
f Eu LSPREADER , Fil R STRIP 'AND REST ORED RIPARIAN Bi SUPPLEMENT
This term must be filled out, printed and submitted
.
.. .
. €fi ..
. ant`
..... ......... .. F' rr o lt?ms Che . I I } r ..:
L' PROJECT INFORMATION
Project name Tag Wood= An
Contact name:: "abecaPeteleon
Phone number:: i9191 n4a Ae00
Date January 22.208
Drainage area number
Jr. DESIGN INFORMATION ,I
For Level Spreaders Receiving Flow From a BMP
Type of BMP.
Drawdown flow from the BMP cis
For Level Spreaders Receiving Flow from the Drainage Area
Drainage area 40,522 it'
Impervious surface area '-4,334
0 fla
Percent impervious .35
....Rational C coefficient 0'.451
Peak flow from the 1 in/hr storm 0.432569559 cfs
Time of concentration min
....Rainfall intensity, 10-yr storm 7;22 in/hr:
Peak flow from the l 0-yr storm 3.123152218 cis
Where Does the Level Spreader Discharge?
To a bioretention cell? N (Y or N)
To a wetland? N D or N)
To a filter strip or riparian buffer? Y (Y or N) .,? .. ., ....., ., .,
....Other (specify)::
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass.: e it
Width of dense ground cover e it
Width of wooded vegetation.:: 50 it
Total width.::: 50 it
Slope (from level lip to to top of bank) 4.3 %
....Are any draws present?.:::: N (Y or N)
....Level Spreader Design.
Fort surface area 28..7 so ft.
Feet of level lip needed per cis 65 fycfs
Answer Y' to one of the following:
Length based on the I in/hr stormy Y : (Y or N)
Length based on the 10-yr, 24-hr storm? N : (Y or N)
Length based on the BMP discharge rate? N : (Y or N)
....Design flow a:42 cfs::
Is a bypass device provided? Y (Y or N) T,;1
::: Form SW401-Level Spreader, Filter Strip, Rest ored Riparian: Buffer Rev 2::: Pads I. and II. Design Silmmarypage 1 of 2
Length of the level lip 28,1.....3 ft
Are level spreaders in series?:: N : (Y or N)
Bypass Channel Design (if applicable)
Does the bypass discharge through awelland?. N : (Y or N)
Does. the channel enter the stream at an angle? Y
Dimensions of the channel (see: diagram below):
M....... :3 f[ ...................................................
B 2 .2i ft
W I% ft
y 0.28E ft
Peak: velocity in the channel. during the 10-yr,:24-Fr storm 35 cfs
Channel lining material bermudagrazs -mattllog
_.m..?:.. ?------?
ra .:_...... ..................
I ¢ -------------
----------
M p
M
B
:. Form SW401-Level Spreader,. Filter Stnp, Restored Riparian Buffer Rev 2:. :. Parts I. and II. Design Summary, page 2 of 2
GI[.. f2EtgUIREp [T08 C.HE KU8T '
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
I ls Sheet No. s sc to w111 rot else c hl l 4 I? cn 5 «v 1t?d
SS mnsFrv C?-iC? dsc wtn?5 i. -1h?S Sy?eQ-F is nr.?k
1. Plans (4z-6044arger-) of the entire site showing v s \e s v??\eme R\ s4z??? cry
Design at ultimate build-out, ?e my ded
Off-site drainage (if applicable),
-Delineated drainage basins(ifelude-RatienalGGoefficientpeHiasin{Fln(s tS r?cWded iC? WJ?L
-Forebay(ifapplicable), «c c\ ?S c«lc?\ F cns,
High flow bypass system,
Maintenance access,
911 - Raserded drainage easement and public right of way (ROW), and
- Boundaries of drainage easement:
<& p 2. Plan details (1" = 30 or larger) for the level spreader showing.
Forebay (if applicable),
- High flow bypass system,
One foot topo lines between the level lip and top of stream bank,
*,Y, -Reperded-drainage easement and
- Design at ultimate build-out
_1 ?5! 14 c; ih 3. Section view of the level spreader (1r -z M er) showing 17e}a \ d oN- -b SGU\l4.
Underdrain system (if applicable),
Level lip;
- Upslope channel, and
- Downslope filter fabric.
q ?t 4. A dale stamped photograph of the filter strip that clearly shows the type of vegetation that is present
A d ??-? 2.:-ra??z.c>r? , s 3 o?l v" ' akl tnowever ?1 t ptnc?S : :
5. An assurance thaTthe installed system will imeet design specifications upon Initial operation once the
project is complete and the entire drainage area is stabilized.
?J 3.U4 t,la 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized.
nn1 /?_ t° a D1?5 7. The supporting calculations.
1?SV (k' : 5 8. A copy of the signed and notarized inspection and maintenance (AM) agreement.
9. A cony of the deed restriction.
G Is pct G? r?n1 y Le dew conk ccv 4vForm c oSCt c s? x vi-Zs c'n
?!?- 4-?ri?Se 1e?2\ sp?ea?e?rs ?za?? +h?,?r ?^p????-+er?c;.??ces
? -r}?ls ?s F7erd?c\c? ?: cv?l o? -\4?e S-F-orn?.,uct-FeV ?\c`vi.
Form SW401-Level Spreader Filter Strip Restored Riparian Buffer-Rev 2 Part III page 1 of 1

aAg t.?
r
r
'4d
NCDENR
STOPMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION AP PLICATION FORM
LEVEL SPREADER PIL I R STRIP AND REST ORED 5SIPA'PI'D BUFFER SUPPLEMENT
This form must be filled out, printed and submitted.
Do Rog a gns ,..Atl rt'h'flrnwWlePa fin
Ad.;. edf : ,k g akv o0b'Aft df. ... W'.-
!I. PROJECT INFORMATION
Project name Tait Woods East
....Contact name Rebecca Peterson
Phone number:: i9t9i 846-.5500
....Date iar.1ay22 ?C07
....Drainage area number
L r'pESION INFORMATION
For Level Spreaders Receiving FloW From:a B41P
....Type of 8MP
Drawdown flow from the BMP:: cfs
For Level Spreaders Receiving Flow from the Drainage Area
Drainage area.: 70038 ft2.:
Impervious surface area 26,463 ft2
Percent impervious 0,37 :(.Ta=}`f
....Rational C coefficient OA81
Peak flow from the l In/hr storm 0.780222635 : cis
....Time of concentration min
Rainfall intensity, 10-yr storm 7.22 : In/hr:
Peak flow from the 10-yr storm 5.633207428 cis
Where Does the Level Spreader Discharge?
To a bioretention cell? N :. (Y or N)
To a wetland?.: N (Y or N)
To a filter strip or riparian buffer? Y (Y or N) I ,a,:, f ar° ? ri(; !hw? 7:
....Other (specify)
Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass.: ft
Width of dense ground cover:: it
Width of wooded vegetation::: bo : it
....Total width:::: 53 ft
....Slope (from level lip to to top of bank) ..589 : %
....Are any draws present? .:::: N (Y or N)
Level Spreader Design
Forobay surface area 52,9 art it ;'K
Feet of level lip needed per cfs 65 fJcfs
....Answer "Y" to one of the fallowing.
Length based on the 1 in/hr storm? Y (Y or N)
Length based on the 10-yr, 24-hr storm? N (Y or N)
Length based on the BMP discharge rate? N (Y or N)
Design flow 878 cis
Is a bypass device provided?.. ?.Y (Y or NI ",Y :..........................................
Form SW401-Level Spreader, Filter Strip,. Res tored Riparian Buffer Rev 2 Pads and 11 . Design Summary, page 1 01`2
'
.::Length of the level lip 50.32 ft CK.
Are level spreaders in series?:: N (Y or N)
.::Bypass Channel Design (if applicable)
Does the bypass: discharge through a wetland? N. (Y or. N)
.::Does the channel enter the stream at an angle?
Dimensions of the channel (see diagram below):
8 `Ls f[.:
W .42„4 ft
y 0.83i ft
Peak velocity in the channel. during the 10-yr,:24-hr, storm 4.8 cis
Channel lining material hermudagrass / ratting
M
::: Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer Rev 2 Parts and II. Design Summary, page 2 of 2'
-D # la
n
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No. Tviis stole wi11- of ?z cvc\?l ( ?} cn s? v dr ?d
sf ?ns c? dre w•nr?s ??' +h?S S`? -k' iS nu-F
J J _ 41 I r 1• Plans (d 5(i orlarger)ofthe?entire2siteteshowing: owing v s \e o' surn\eme t\ s4 ?e? co-
Design at ultimate build-out, bz cv dP
Off-site drainage (if applicable),
Delineated drainage basins (ir;elude-Rational--Goefficient-per-basin), finis ;nclvd.?d Ln V"-Je
U}F ch.2) c lc?to \ nS
Forebay (if applicable),
High flow bypass system,
Maintenance access,
- Reeerded drainage easement and public right of way (ROW), and
Boundaries of drainage easement.
?Sf lb G? l(0 2. Plan details (42--- frer4aW) for the level spreader showing: W :A\ nc-?
-Forebay(ifapplicable), recti cnab\? P(? cost= cktvd
High flow bypass system; s cc; scrvC? cn drew wa,-
- One foot topo lines between the level lip and top of stream bank,"_
v? -Reeerded-drainage easement, and s ptale ve?}<z\ stn s- c=ti
n /} - Design at ultimate build-out. 6c p
IL ,Jt_ !"I lto 3. Section view of the level spreader ( ge) showing ?` ?;\ o? }b \ ? -
- Underlain system (if applicable),
- Level lip;
- Upslope channel; and
- Downslope filter fabric.
A 4. A-dal photograph of the filter strip that clearly shows the type of vegetation that is present
A cyc?{ e :S+ckm? is nog- ix1: rho-t-o, V\ci"JeQ r: _\A ptAo'-WS
I.,J P.rQ, t0.?.zVl ot? ?0 /31G?. r.^?. to/31/p-}
5. An assurance that the Installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
_ f3 ?? tla 6. A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized;
i°57R to 7. The supporting calculations.
8. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
9. A copy of the deed restriction. -A sL
# S-t=C- nc c? renNy ?v ?e? can?rCc ke dorm CcvnSch sv x v`s\Gn
QeY- njpse leie_k Sp 2c -Irs cxnd T?ztr r Pwr ercv?ces.
Th(s s -(jex-\A N \CS c.?rovCk a? -thy sl o? v wa p1G?n
Form: SW401-Level Spreader, Filter Strip Restored: Riparian Buffer-Rev2 Part Il 1, page l of 1
bqW
,

WDENR
STO RMWATER MANAGEMENT P ERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
LEVEL SP,._AD®R.. IL I R1 STRIP AND REST ORED 1FIPARIMN ISM, ER SUPPLElulENT
This form must be filled out, printed and submitted.
(S ;fit {a f?tff mthe vst?d
111-P ROdEGT INFORMATION J
Project name Taft VyJ ods Casa
Contact name:: reb^?ca Fehdso^:..
Phone number ,91gt a4s"9i,0 .. ...........
Date darurrv22 2008
-
Drainage area number DA'/ u
II, DESIGN INFORMATION
For Level Spreaders Receiving Flow From a: BMP
:Type of :BMP:::
Drawoown flow from the BMP:: cfs::
For Level Spreaders Receiving Flow from the Drai nage Area
Drainage area:: 121,895 fe::
Impervious surface area 31.5d5 ftz::
..:::Percent impervious ...0.26 : (.ZL- ir)
Rational C coefficient 6:394
Peak flow from the 1 Whir storm .:1.102539715 : cfs::
Time of concentration min
Rainfall intensity, 10-yr storm:: 722 in/hr:
Peak:flow from the 10-yr storm 7.960336745 : cis::
.::Where Does the Level Spreader Discharge?
To a bioretention cell? N (Y or N)
To a wetland?:: N (Y or N)
Toafilter strip orriparian buffer? :'e (YorN) ?.<.?,(rn.l-i-§.
,. ..

: :::: ::::
Other (specify)
.......
.::Filter Strip or Riparian Buffer Characterization (if applicable)
Width of grass:: n If
Width of dense ground cover:: ft
Width of wooded vegetatiod to : ft
Total width::: :50 : ft
Slope (from level lip to to top of bank) Z02 : %
Are any draws :present? .:::: N : (Y or N) ;,(::
Level Spreader: Design
Forebay surface area E3.3 : sq ft: 0
Feet of level lip needed per cfs 65 : ft/cfs:
Answer "Y" to one of the following.
Length based on the 1: inshr storm? Y (Y or N)
Length based on the 10-yr, 24-hr storm? N (Y or N)
Length based on the BMP: discharge rate? N mm (Y or N)
Design flow ::: i.1 : cfs:
Is a bypass device provided?:: Y : (Y or N) T
Form SW401-1-evel Spreader, Filter Strip, Restored Riparian Buffer Rev.2 Parts 1. and 11. Design Summary, page 1 of 2
Length of the level lip 711 ft L r ,I s: ...* ..:
Are level spreaders in series?:: N (Y or N)
....Bypass Channel Design (if applicable).
Does the bypass discharge through a wetland? N (Y or N)
Does the channel enter the stream at an angle? Y
Dimensions of the channel (see diagram below):
M :......3 ft::
B 3,1 ft
W G'.1; ft
y ...0.452 ft.:
Peak velocity in the channel during the 10-yr, 24-hr storm 3,; ofs
....Channel lining material oermudfiglass ; rreaiirg
t '
M
Form SW401-Level Spreader, Filter Strip, Restored Riparian Buffer-Rev.2 Parts 1'. and 11. Design Summary, page 2 of 2
17H *s ?
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No. L- r s sc le wl\1; no} ?easrnchl l} sF«v clctird
Sj7 thie2 citesho
1: Plans (A ar FargeF) of the entire site showing:
ing: vrs e ; o s u \e e t \ s\ ?e? c u
_ - Design at ultimate build-out, b e- p<-Dv6d2d
- Off-site drainage (if applicable),
Delineated drainage basins(inelude-Ratienal-Gcoefficient-per-basin), 1n Es ,rlclUded +r\ ?L
- Forebay (if applicable); acch2d c nlc?\ x c S:
- High flow bypass system,
Maintenance access;
- Reoerded drainage easement and public right of way (ROV), and
- Boundaries of drainage easement.
I ?r 11 ? is 2. Plan details ( =39 eHa geF) for the level spreader showing: \ 4'iis ` €' ?2 uo \\ 4??'
- Forebay (if applicable), r°Z exie hl.? A4-?$ co stczv dca d
- High flow bypass system, Stz? co\cvl cwcCk?v c? r v ncJs .
'J 01
- One foot topo lines between the level lip and top of stream bank, r`cl" e r
- Resor9ed drainage easement, and s ?»1e mex?+o 1 s4 ?t cc?n L
Design at ultimate build-out, u lctd .
14"a? lta 3; Section view of the level spreader (1= ?9 ?Na ges) showingkvl\ nG? o cct\C.
- Underdrain system (if applicable),
- Level lip
- Upslope channel and
- Downslope filter fabric.
f ? Lt
4. A-date-stamped photograph of the filter strip that clearly shows the type of vegetation that is present
A: dC.Ve S'cc?? iS noT ac+V- c ?4io-\"ta, ant -+ever, ?tiSt p4w`K?S ::
-9 \0 I a; G-4
5. An assurance thaEthe Installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
3 cF IL 6; A construction sequence that shows how the level spreader will be protected from sediment until the entire
drainage area is stabilized.
G) t_5 ?Dk - 7. The supporting calculations.
kk: & A copy of the signed and notarized inspection and maintenance (I&M) agreement:
9. A copy of the deed restriction.
SLir,C rs cicr c??'zu?-Ky ??n?ew ccn?C-? 1-:, ??r?ort?n cc*nS?ci?c? su?x>rv?s\c^n
e k4 xSe le ZA srp rs ,,tncl, =nz\r pwr+e ?czs.
?h s aS 7er-c?tr\c, evert ?? Vne- si o wee F? pie ?'
::: Form:SW401 Level Spreader, Filter Strip, Restored Riparian Buffer-Rev .2 Part III, page 1. of 1 : : :
SOIL & ENVIRONMENTAL CONSULTANTS, ISA
ATTACHMENT III
FILTER STRIP, RESTORED BUFFER, AND LEVEL SPREADER INSPECTION
MAINTAINANCE AGREEMENTS

Permit Number:
(to be provided by DWQJ
Drainage Area Number: DA # 1
Fitter Strip, Restored Riparian Buffer and Level Spreader
Inspection and. Maintenance Agreement
I will keep a maintenance record on fl- is BivhP. This maintenance record will be kept in a
log in a known set location. Any deficient BMW elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the Blvil.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
- Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary,
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater than 10 Inch (or 1.5 inches if in a Coastal County),
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: flow I will remediate the problem:
The entire filter strip Trash/debris is present. Remove the trash/ debris.
s stem
The flow splitter device "the flow splitter device is Unclog the conveyance and dispose
(if applicable) clogged. of any sediment off-site.
The flow splitter device is Make any necessary repairs or
damaged. replace if damage is too large for
re air.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer 1&M-Rev.2 Page 1 of 3
BMP element: Potential problem: How l will remediate the problem:
The swage and the level The Swale is dogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
lime anda one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swage or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control:
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material.
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove: the gully, and then: plant a: :
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed:
Plants are dead, diseased or Determine the source of the
dying, problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet. 401 Oversight Unit at 919-733-1786:
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 2 of 3
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. 1 agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible parry.
Project name: Taft Woods East, Level Spreader Design
BMP drainage area number: DA #1
Print name: Lauraleen. LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court, Clayton, NC 25727
Phone: [phone]
Signature:
Date: Zy ?7
Note The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
114b,, S. 25//t i4ftn , a Notary Public for the State of
?Qti d 1 eMI_lxl County of &? n do hereby certify that
p, ?l personally appeared before me this
day of o !? and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires, F
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&,vl-Rev.2 Page 3 of 3
Permit Number:
(to be provided by DWQ)
Drainage Area Number: DA #2
Filter Strip, Restored Riparian Buffet and Level Spreader
Inspection and Maintenance Agreement
I will keep a maintenance record on this BNIP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary.
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater than 1.0 inch (or 1.5 inches if a Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How will r, mediate the problem:
The entire filter strip Trash/ debris is present. Remove the trash/ debris.
system
The flow splitter device The flow sputter device is Unclog the conveyance and dispose
(if applicable) clogged. of any sediment off-site.
The flow sputter device is Make any necessary repairs or
damaged. replace if damage is too large for
repair.
Form SwU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page I of 3
BMP element: Potential problem: low I will remediatethe Tblern:
The swale and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
time anda one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material.
The alter strip Grass is too short or too long Maintain grass at a height of
if applicable), approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time ferfilizer application.
Sediment is building up on Remove the sediment and
the filter strip, restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water:
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet. 401 Oversight Unit at 919-733-1786.
Form SWU40i-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 2 of 3
Permit Number:
(to be provided by DVIQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
BAIP drainage area number: DA #2
Print name: Lauraleen, LLC c/o George Schlecht
Title: Manaeer
Address: 3515 Oucen Anne Court, Clayton. NC 25727
Phone: [phone] - -74
Signature:
Date: Z / 5A
Note: The legally responsible party should not be a homeowners association unless more than 50%e of
the lots have been sold and a resident of the subdivision has been named the president.
1, ?. 111no p q , a Notary Public for the State of
11 , County of ZO-hn-,-,4DY1 do hereby certify that
6pome' eWA.P,6t personally appeared before me this
day of, I y'7and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
NVitness my hand and official seal,
SEAL ?°
My commission expires__ tP fu t k.ru 00//
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 3 of 3
Permit Number:
(to be provided by DWQJ
Drainage Area Number: DA #3
Filter Strip, Restored Riparian Buffer and Level Spreader
Inspection and. maintenance Agreement
I will keep a maintenance record on this BMP: This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
- Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to groin as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary:
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 224 hours
after every storm event greater than 1.0 inch (or 1,5 inches if in a Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How I will remediate the problem:
The entire filter strip Trash/debris is present. Remove the trash/ debris.
s stem
The flow splitter device The flow splitter device is Unclog the conveyance and dispose
(if applicable) clogged. of any sediment off-site.
The flow sputter device is Make any necessary repairs or
damaged. replace if damage is too large for
repair.
Form SWU4Ql-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 1 of 3
BM PP element: Potential' roblem: flow l will remediate the problem:
The sw ale and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed remove the gully, and then
reestablish proper erosion control.
_
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and them plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabiiize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet. 401 Oversight Unit at 919-733-1786.
Form S WU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 2 of 3
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
BMP drainage area number; DA #3
Print name: Lauraleen, LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court, Clayton, NC 25727
Phone: [phone]
Signature: f i -v
Date: i zr 9',14 7
Note:. The legally responsible party should not be a homeowners association unless more than 50% of
the tots have been sold and a resident of the subdivision has been named the president.
1,///t1 A`fp" 1 a Notary Public for the State of
e Di l n z, > County of foh n n do hereby certify that
apnMO, Se,Iie t personally appeared before me this
day oQpti aWW7 and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires D
Form SXArU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&clvt-Rev.2 Page 3 of 3
Permit Number:
(to be provided by DWQ)
Drainage Area Number: DA #3
Wet Detention Basin Inspection and. Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public; and the removal efficiency of the BMP.
The wet detention basin system is defined as the wet detention basin,
pretreatment including forebays and the vegetated filter if one is provided.
This system (check one):
? does R does not incorporate a vegetated filter at the outlet.
This system (check one).
? does ? does not incorporate pretreatment other than a forebay.
Important maintenance procedures:
Immediately after the wet detention basin is established; lmdscaping plants, the
pla is en the vegetate she f and perimeter of the bas should be watered twice
weekly if needed, until the plants become established (commonly six weeks):
- No portion of the wet detention pond should be fertilized after the first initial
fertilization that is required to establish the landscaping plants an the vegetate
shelf.
Stable groundcover should be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
If the basin must be drained for an emergency or to perform maintenance, the
flushing of sediment through the emergency drain should be minimized to the
maximum extent practical.
- Once a year, a dam safety expert should inspect the embankment.
After the wet detention pond is established, it should be inspected once a month and
within 24 hours after every storm event greater than 1,0 inches (or 1.5 inches if in a
Coastal County). Records of inspection and maintenance should be kept in a known set
location and must be available upon request:
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential roblem: How I will remediate the problem:
The entire BMP Trash/debris is present. Remove the trash/debris.
The perimeter of the wet Areas of bare soil and/or Regrade the soil if necessary to
detention basin erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Form SW401-Wet Detention Basin I&M-Rev.2
Permit Number::..
(to be provided by DWQ)
Drainage Area Number: DA #3
Vegetation is too short or too Maintain vegetation at a height of
long. approximately six inches.
BMP element: Potential problem: How I will remediate the problem:
The inlet device: pipe or The pipe is clogged. Unclog the pipe. Dispose of the
swale sediment off site:
The pipe is cracked or Replace the pipe.
otherwise damaged.
Erosion is occurring in the Regrade the swale if necessary to
swale. smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
The forebay Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design depth for possible. Remove the sediment and
sediment storage. dispose of it in a location where it
will not cause impacts to streams or
the BMP:
Erosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
revent future erosion problems,
Weeds are present. a Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
_ the lams rather than spra in
The °t? _
Best professional practices Prune according to best professional
landscaved vegetation show that pruning is needed practices
to maintain optimal plant
health.
Plants are dead, diseased or Determine the source of the
dying: problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary__
Weeds are present. Remove the weeds, preferably by
hand. If pesticide is used, wipe it on
the plants rather than spraa T
The main treatment area Sediment has accumulated to Search for the source of the
a depth greater than the sediment and remedy the problem if
original design sediment possible. Remove the sediment and
storage depth. dispose of it in a location where it
will not cause impacts to streams or
the BMP:
Algal growth covers over Consult a professional to remove
50% of the area. and control the algal growth.
Cattails, phragmites or other Remove the plants by wiping them
invasive plants cover 50% of with pesticide (do not spray).
the basin surface.
Form SW401-Wet Detention Basin i&M-Rev.2
Permit Number:
(to be provided by DWQ)
Drainage Area Number: DA #3
BMP element: Potential roblem: How 'I will remediate the problem:
The embankment Shrubs have started to grow Remove shrubs immediately:
on the embankment.
Evidence of muskrat or Use traps to remove muskrats and
beaver activity is present. consult a professional to remove
beavers:
A tree has started to grow on Consult a dam safety specialist to
the embankment. remove the tree.
An annual inspection by an Make all needed repairs.
appropriate professional
shows that the embankment
needs repair.
The outlet device Clogging has occurred. Clean out the outlet device. Dispose
of the sediment off-site.
The outlet device is damaged Repair or replace the outlet device.
The receiving water Erosion or other signs of Contact the local NC Division of
damage have occurred at the Water Quality Regional Office, or
outlet. the 401 Oversight Unit at 919-733-
1786.
The measuring device used to determine the sediment elevation shall be such
that it will give an accurate depth reading and not readily penetrate into
accumulated sediments.
When the permanent pool depth reads 8.0 feet in the main pond, the sediment
shall be removed.
When the permanent pool depth reads 1.0 feet in the forebay, the sediment
shall be removed.
BASIN DIAGRAM
(fill in the blanks)
0 Permanent Pool Elevation 189.0
Sediment \Rmoval El. 189.0 ? reerman . t Pool
e SechmentRemovalElevahon18i.0 Volume
Bottevation 187.0 n. ------------- --------- -- --= ---- - ement Bottom Elevation 180.0 1-ft n:
Storage: Sediment
Storage
FOREBAY MAIN POND
Form SW401-Wet Detention Basin I&M-Rev.2
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
BMP drainage area number: DA 93
Print name: Lauraleen, LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court, Clayton, NC 25727
Phone: [phone]
Signature:
Date: n O
Note:: The legally responsible party should not be a. homeowners: association unless more than 50% of::
the lots have been sold and`aresident of the subdivision has been named the president.
I, /?da_ 5 __. L ffindlb-er 1aNotaryPublicfortheStateof
No r46 C nn_Lt f) IQA_County of 70kl f); On do hereby certify that
C:5 eDT-Qe, C SCI-) I Q 7? r personally appeared before me this, a1
day of and acknowledge the due execution of the
forgoing wet detention basin maintenance requirements. Witness my hand and official
seal, t/
LLille
?.?
J RY li e
V
?JoN CO`
14\\
SEAL
My commission expires
Form SW401-Wet Detention Basin 1&M-Rev.2
Permit Number:
(to be provided by DWQ)
Drainage Area Number: DA #4
Filter Strip, Restored Riparian Buffer and Level Spreader
Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BIVIP.
Important maintenance procedures:
Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
- Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary:
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater than 1.0 Inch (or 1.5 inches if in a'Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: Hose I will remediate the problem:
The entire filter strip Trash/debris is present. Remove the trasb/debris.
system
The flow splitter device The flow splitter device is Unclog the conveyance and dispose
(if applicable) clogged. of an sediment off-site.
The flow sputter device is Make any necessary repairs or
damaged. replace if damage is too large for
re air
Form SWU401-Level Spreader, Fitter Strip, Restored Riparian Butler I&M-Rev.2 Page I of 3
BMP element: Potential problem: How I will remediate the problem:
The swale and the level The swaleis clogged: with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut; eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed if: water until it is established. Provide
lime anda one-time fertilizer
application.
Trees or shrubs have begun Remove them
to grow on the swale or just
dov7mlo e of the level li .
The bypass channel Areas of bare soil and/or Regrade the soil ff necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control:
Turf reinforcement is Study the site to see ff a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material.
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). a roxj tel three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying: problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species: possible. ff pesticide is used, do not
allow it to get into the receiving
water:
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet. 401 Oversight Unit at 919-733-1786.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&hl-Rev.2 Page 2 of 3
Permit plumber:
(to be provided by DWQ)
I acknowledge and agree by my signature below that 1 am responsible for the
performance of the maintenance procedures fisted above. i agree to notify DWQ`of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
BMP drainage area number: DA #4
Print name: Lauraleen, LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court, Clayton, NQ 25727
Phone: [phone]
Signature
Date: i s-?
Note:. The legally responsible parry should not be a homeowners association unless more than 50%0 of
the lots have been sold` and a resident of the subdivision has been named the president.
I> t ?ix ?. /fir o(?D l l a Notary Public for the State of
a phi nib, , County of _J h do hereby certi?ty that
(-Pr)rne, Sa WeGh personally appeared before me this
day of71) b , and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires 1°e tVb- m1/
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer 1&M-Rev.2 Page 3 of 3
Permit Number:
(to be provided by UWQ)
Drainage Area Number:_ DA #i5
Filter Strip, Restored Riparian Buffer and Level Spreader
Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BPfP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
- Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NTIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary:
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after event storm event greater than 1.9 inch (or 1.5 inches if in a Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potentialproblem: Flow will remediatethe roblem:
The entire filter strip Trash/debris is present. Remove the trash/ debris.
system:.
The flow spiitter devise The flow sputter device is Unclog the conveyance and dispose
(if applicable) clogged. of an sediment off-site.
The flow sputter device is Make any necessary repairs or
damaged. replace if damage is too large for
re air:
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 1 of 3
BMP element: Potential roblem: How 1 will remediate the problem:
The swale and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip, sestabilize the soil with vegetation if
necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed
_
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species, possible. If pesticide is used, do not
allow it to get into the receiving
water:
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
f outlet. 401 Oversight Unit at 919-733-1786.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 2 of 3
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. 1 agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
B11P drainage area number: DA #5
Print naive: Lauraleen. LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court, Clayton, NC 25727
Phone: [phone]
Signature:~
Date: 7
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, , , F /l n a Notary Public for the State of
?69h AV b,_, County of Jo x d , do hereby certify that
601"I s personally appeared before me this _
day of y G )Dog and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires rP'_brLk&r-tq 4,
cam!
Form TWO I -Level Spreader, Filter Strip, Restored Riparian Buffer I&IM-Rev.2 Page 3 of 3
Permit Number:
(to be provided by D?yQ)
Drainage Area Number: DA #6
Filter Strip, Restored Riparian Buffer and Level Spreader
Inspection and Maintenance Agreement
l will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BIMP.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
- Once a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimum pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary;
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after evety storm event greater than 1.0 inch for 1.5 inches if in a Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How twill remediate the problem:_
't'he entire filter strip Trash/ debris is present. Remove the trash/ debris.
stem
The flow splitter device The flow sputter device is Unclog the conveyance and dispose
(if applicable) clogged. of an sediment off-site.
The flow sputter device is Make any necessary repairs or
damaged. replace if damage is too large for
repair.
Form SWU401-Level Spreader, Filter Ship, Restored Riparian Buffer I&M-Rev.2 Page l of 3
BivtP element: potential problem: flow I will remediate the problem:
The swage and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
lime anda one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material.
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabilize the soil with vegetation if
necessary. Provide lime and a one-
: :time fertilizer a lication.::: :
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time.
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water:
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet: 401Oversight Unit at 919.733-1786:
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 2 of 3
Permit Number:
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify LWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, Level Spreader Design
BMP drainage area number: DA #6
Print name: Lauraleen. LLC c/o George Schlecht
Title: Manaeer
Address: 3515 Queen Anne Court. Clayton, NC 25727
Phone: [phone]
Signature:-
Date: i f -7
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, S /fr ob n a Notary Public for the State of
L?L1County of 11 do hereby certify that
g? 9QA) f e A t personally appeared before me this
J , and acknowledge the due execution of the
day of "9Y1Do
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
SEAL
My commission expires FP_6, t t c !j
Form SXVU401-Level Spreader, Filter Strip, Restored Riparian Buffer Ik&M-Rev.2 Page 3 of 3
Permit Number:
(to be provided by DWQ)
Drainage Area Number: DA #7
Filter Strip, Restored Riparian Ruffer std Level Spreader
Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
- Immediately after the filter strip is established, any newly planted vegetation
will be watered twice weekly if needed until the plants become established
(commonly six weeks).
Croce a year, the filter strip will be reseeded to maintain a dense growth of
vegetation
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the vegetation.
Two to three times a year, grass filter strips will be mowed and the clippings
harvested to promote the growth of thick vegetation with optimism pollutant
removal efficiency. Turf grass should not be cut shorter than 3 to 5 inches and
may be allowed to grow as tall as 12 inches depending on aesthetic requirements
(NIPC,1993). Forested filter strips do not require this type of maintenance.
- Once a year, the soil will be aerated if necessary;
- Once a year, soil pH will be tested and lime will be added if necessary.
After the filter strip is established, it will be inspected quarterly and within 24 hours
after every storm event greater thane't.0 inch (or 1.5 inches if in a Coastal County).
Records of inspection and maintenance will be kept in a known set location and will be
available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BIYIP element: Potential problem: How I will remediate the rnblem:
The entire filter strip Trash/debris is present. Remove the trash/ debris.
system
The flow splitter device The flow splitter device is Unclog the conveyance and dispose
(if applicable) clogged. of an sediment off-site.
The flow splitter device is Make any necessary repairs or
damaged. replace if damage is too large for
, repair.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I& M-Rev.2 Page 1 of 3
BMP element: Potential problem: How I will remedlate the problem:
The swale and the level The swale is clogged with Remove the sediment and dispose
lip sediment. of it off-site.
The level lip is cracked, Repair or replace lip.
settled, undercut, eroded or
otherwise damaged.
There is erosion around the Regrade the soil to create a berm
end of the level spreader that that is higher than the level lip, and
shows stormwater has then plant a ground cover and
bypassed it. water until it is established. Provide
lime and a one-time fertilizer
application.
Trees or shrubs have begun Remove them.
to grow on the swale or just
downslo e of the level lip.
The bypass channel Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then
reestablish proper erosion control.
Turf reinforcement is Study the site to see if a larger
damaged or ripap is rolling bypass channel is needed (enlarge if
downhill. necessary). After this, reestablish
the erosion control material
The filter strip Grass is too short or too long Maintain grass at a height of
if applicable). approximately three to six inches.
Areas of bare soil and/or Regrade the soil if necessary to
erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Sediment is building up on Remove the sediment and
the filter strip. restabilize the soil with vegetation if
0 necessary. Provide lime and a one-
time fertilizer application.
Plants are desiccated. Provide additional irrigation and
fertilizer as needed.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application.
Nuisance vegetation is Remove vegetation by hand if
choking out desirable species. possible. If pesticide is used, do not
allow it to get into the receiving
water.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality local Regional Office, or the
outlet: 401 Oversight Unit at 919-733-1786.
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer IP, M-Rev.2 Page 2 of 3
Permit Number
(to be provided by DWQ)
I acknowledge and agree by my signature below that I am responsible for the
performance of the maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Project name: Taft Woods East, evel Spreader DesigLI
BI VP drainage area number: DA #7
Print name: Lauraleen, LLC c/o George Schlecht
Title: Manager
Address: 3515 Queen Anne Court Clayton, NC 25727
Phone: [phone]
Signature: /-?
Date: 7
Note: The legally responsible party should not be a homeowners association unless more than 50% of
the lots have been sold and a resident of the subdivision has been named the president.
I, > °a /11n tL, a Notary Public for the State of
_ (1d /?f?y1 , County _'b nAt6_ n do hereby certify that
Pm 1 ?Gt personally appeared before me this
day of eA blr_, J , and acknowledge the due execution of the
forgoing filter strip, riparian buffer, and/or level spreader maintenance requirements.
Witness my hand and official seal,
anrv /
My commission expires 1-a of to Y abll
Form SWU401-Level Spreader, Filter Strip, Restored Riparian Buffer I&M-Rev.2 Page 3 of 3
SOIL, & ENVIRONMENTAL CONSULTANTS, PA
ATTACHMENT IV
RIPARIAN BUFFER AUTHORIZATION PRE -CONSTRUCTION NOTICE

1. Processing
1. Check all of the approval(s) requested for this project:
Section 404 Permit ?I Riparian or Watershed Buffer Rules
Section 10 Permit ? Isolated Wetland Permit from DWQ
401 Water Quality Certification ? Express 401 Water Quality Certification
2. Nationwide, Regional or General Permit Number(s) Requested: N/A
3. If this notification is solely a courtesy copy because written approval for the 401 Certification
is not required, check here: ?
4. If payment into the North Carolina Ecosystem Enhancement Program (NCEEP) is proposed
for mitigation of impacts, attach the acceptance letter from NCEEP, complete section VIII,
and check here: ?
5. If your project is located in any of North Carolina's twenty coastal counties (listed on page
4), and the project is within a North Carolina Division of Coastal Management Area of
Environmental Concern (see the top of page 2 for further details), check here:
[l. Applicant Information
1. Owner/Applicant Information
Name: Lauraleen LLC (Attn: George Schlecht)
Mailing Address: 3515 Oueen Ann Drive
Clayton, N.C. 27527
Telephone Number: 919-427-8056 Fax Number: 919-553-9196
E-mail Address: N/A
2. Agent/Consultant Information (A signed and dated copy of the Agent Authorization letter
must be attached if the Agent has signatory authority for the owner/applicant.)
Name: Rebecca Peterson PE
Company Affiliation: Soil & Environmental Consultants, PA
Mailing Address: 11010 Raven Ridge Road
Raleigh, NC 27614
Telephone Number: [phone] Fax Number: [phone]
E-mail Address: [e-mail]
Page of 9
III. Project; Information
Attach a vicinity map clearly showing the location of the property with respect to local
landmarks such as towns, rivers, and roads. Also provide a detailed site plan showing property
boundaries and development plans in relation to surrounding properties Both the vicinity map
and site plan must include a scale and north arrow. The specific footprints of all buildings,
impervious surfaces, or other facilities must be included. If possible, the maps and plans should
include the appropriate USGS Topographic Quad Map and NRCS Soil Survey with the property
boundaries outlined. Plan drawings, or other maps may be included at the applicant's discretion,
so long as the property is clearly defined. For administrative and distribution purposes, the
USACE requires information to be submitted on sheets no larger than 11 by 17-inch format;
however, DWQ may accept paperwork of any size. DWQ prefers full-size construction
drawings rather than a sequential sheet version of the full-size plans. If full-size plans are
reduced to a small scale such that the final version is illegible, the applicant will be informed that
the project has been placed on hold until decipherable maps are provided.
1. Name of project: Taftwoods East-Section 2
2. T.I.P. Project Number or State Project Number (NCDOT Only): N/A
3. Property Identification Number (Tax PIN): 1689-73-8518&1689-94-4588
4. Location
County: Johnston Nearest Town: Flowers
Subdivision name (include phase/lot number): Taftwoods East-Section 2
Directions to site (include road numbers, landmarks; etc.): The site is located north of
Motorcycle Road (S.R. 1704 and is approximately 1,000 feet northwest of the intersection of
Motorcycle Road and Highway 42 in Flowers N.C.
5. Site coordinates, if available (UTM or Lat/Long): 35.6556-N . 78.3648-W
(Note - If project is linear, such as a road or utility line, attach a sheet that separately lists the
coordinates for each crossing of a distinct waterbody.)
6. Property size (acres): t 126 acres (proiectarea t 83 acres)
7. Nearest body of water (stream/river/sound/ocean/lake); UT to Mill Creek
8. River Basin; Neuse (03-04-02 27-39 WS-IV NSW)
(Note this must be one of North Carolina's seventeen designated major river basins. The
River Basin map is available at http://h2o.enr.state.nc.us/adlli!l/mas/.)
9. Describe the existing conditions on the site and general land use in the vicinity of the project
at the time of this application: A majority of the site is currently wooded and undeveloped,
with exception to the "Existing Section One" area on the southwest portion of the site.
Page 2 of 9
10. Describe the overall project in detail, including the type of equipment to be used: The
proposed project is a residential development Riparian buffer impacts will be the result of 6
bypass channels associated with level spreaders
11. Explain the purpose of the proposed work: The purpose of the residential subdivision is to
provide needed housing to meet the growing demands for this area. The purnose of the level
spreaders is to provide diffuse flow for stormwater that has been concentrated as a result of
the development Riparian buffer authorizations will be necessary for bypass channels on 5
of the 7 proposed level spreaders
IV. Prior Project 141story
If jurisdictional determinations and/or permits have been requested and/or obtained for this
project (including all prior phases of the same subdivision) in the past, please explain. Include
the USAGE Action ID Number, DWQ Project Number, application date, and date permits and
certifications were issued or withdrawn. Provide photocopies of previously issued permits,
certifications or other useful information. Describe previously approved wetland, stream and
buffer impacts; along with associated mitigation (where applicable). If this is a NCDOT project,
list and describe permits issued for prior segments of the same T.I.P. project, along with
construction schedules. A 401 Water Quality Certification was issued by DWQ on October 15,
2007 permitting 258 linear feet of perennial stream impacts 11,686 square feet of Zone 2 Neuse
buffer impacts and 7,374 square feet of Zone 1 Neuse buffer impacts NCEEP issued an
acceptance letter to receive payment for compensatory mitigation for the 258 linear feet of
perennial stream impacts On October 1 2007, S&EC requested authorization from the US
Army Corps of Engineers (USAGE) to utilize a Nationwide Permit 29 for the above referenced
stream impacts. A Notification of Statutory Status for this request was submitted to the USAGE
on November 20, 2007 Photocopies of all issued permits and other useful information are
attached.
V. Future Project Plans
Are any future permit requests anticipated for this project? If so, describe the anticipated work,
and provide justification for the exclusion of this work from the current application.
There are not future permits known to be required at this time.
VI. Proposed Impacts to Waters of the United StatesMaters of the Stale
It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
wetlands, open water, and stream channels associated with the project. Each impact must be
listed separately in the tables below (e.g., culvert installation should be listed separately from
riprap dissipater pads). Be sure to indicate if an impact is temporary. All proposed impacts,
permanent and temporary, must be listed, and must be labeled and clearly identifiable on an
accompanying site plan. All wetlands and waters, and all streams (intermittent and perennial)
should be shown on a delineation map, whether or not impacts are proposed to these systems.
Wetland and stream evaluation and delineation forms should be included as appropriate.
Photographs may be included at the applicant's discretion. If this proposed impact is strictly for
Page 3 of 9
wetland or stream mitigation, list and describe the impact in Section VIII below. If additional
space is needed for listing or description, please attach a separate sheet.
1. Provide a written description of the proposed impacts: There are no proposed facts to
jurisdictional waters within this application request
2. Individually list wetland impacts. Types of impacts include, but are not limited to
mechanized clearing, grading, fill, excavation, flooding, ditching/drainage, etc. For dams,
s arately list impacts due to both structure and floodin .
Wetland Impact Type of Wetland Located within Distance to Area of
Number Type of Impact (e.g., forested, marsh, 100-year
ai n
F [
Nearest
Stream Impact
(acres)
(indicate on map) herbaceous; bog, etc.) (yes/n
yes/no) (linear feet)
N/A N/A N/A N/A N/A N/A

Total Wetland Impact (acres) N/A
3. List the total acreage (estimated) of all existing wetlands on the property: <1 acre
4. Individually list all intermittent and perennial stream impacts. Be sure to identify temporary
impacts. Stream impacts include, but are not limited to placement of fill or culverts, dam
construction, flooding, relocation, stabilization activities (e.g., cement walls, rip-rap, crib
walls, gabions, etc.), excavation, ditching/straightening, etc. If stream relocation is proposed,
plans and profiles showing the linear footprint for both the original and relocated streams
must be included. To calculate acreage, multiply length X width, then divide by43,560.
Stream Impact
Perennials
or Average Impact Area of
Number : Stream Name : Type of Impact . Stream Width Length. Impact
(indicate on map) Intermittent? Before Impact (linear feet) (acres)

N/A N/A N/A N/A N/A N/A : N/A..
Total Stream Impact (by length and acreage) N/A
5. Individually list all open water impacts (including lakes, ponds, estuaries, sounds, Atlantic
Ocean and any other water of the U.S.). Open water impacts include, but are not limited to
fill, excavation, dredging, flooding, drainage, bulkheads, etc:
Open Water Impact ea of
Type of Waterbody

Site Number Name of Waterbody

(if applicable)
Type of Impact
(lake, pond, estuary, sound, bay,: pact
:
(indicate on map) ocean, etc.) res)

n /a
?a
a /a
n/a
Total Open Water Impact (acres)
6. List the cumulative impact to all Waters of the U.S. resulting from the project
Stream Impact (acres): 0
Wetland Impact (acres): 0
Open Water Impact (acres): 0
Total Impact to Waters of the U.S. (acres) 0
Total Stream Impact (linear feet): 0
Page 4 of 9
7. Isolated Waters
Do any isolated waters exist on the property? F;J, Yes ? No
Describe all impacts to isolated waters, and include the type of water (wetland or stream) and
the size of the proposed impact (acres or linear feet). Please note that this section only
applies to waters that have specifically been determined to be isolated by the USACE.
There are no impacts proposed to any solated waters onsite.
8. Pond Creation
If construction of a pond is proposed; associated wetland and stream impacts should be
included above in the wetland and stream impact sections. Also, the proposed pond should
be described here and illustrated on any maps included with this application.
Pond to be created in (check all that apply): ? uplands ? stream ? wetlands
Describe the method of construction (e.g., dam/embankment, excavation, installation of
draw-down valve or spillway, etc.): N/A
Proposed use or purpose of pond (e.g., livestock watering, irrigation, aesthetic, trout pond,
local stormwater requirement, etc.): N/A
Current land use in the vicinity of the pond: N/A
Size of watershed draining to pond: N/A Expected pond surface area: N/A
VII. Impact Justification (Avoidance and Minimization)
Specifically describe measures taken to avoid the proposed impacts. It may be useful to provide
information related to site constraints such as topography, building ordinances, accessibility, and
financial viability of the project. The applicant may attach drawings of alternative, lower-impact
site layouts, and explain why these design options were not feasible. Also discuss how impacts
were minimized once the desired site plan was developed. If applicable, discuss construction
techniques to be followed during construction to reduce impacts:
Six _(0 of the seven (7) pro osed level spreaders were designed to provide diffuse flow for storm events 0to and including the 1 in/hrintensity. The current BMP manual requires a _
bypass channel to convey flow resulting from intensities greater than 1 in/hr up to and including
the 10-3r event to through the buffer to the stream. The bypass channel is not necessary if the
level spreader can be desi ng ed to provide diffuse flow for events up to and including the 10-31
event, fiow_ever, none of the level spreaders could be designed for this flow without exceeding
the maximum lengths as defined in the BMP Manual. One (1) level spreader could not be
designed to provide diffuse flow for the irv'hr intensity without exceeding the maximum length
so a wet detention pond has been designed to capture and release stormwater to this level
spreader at the rate associated with the maximum length This pond has enough storage to store
and release the 10-yr event to the level spreader at Yhs rate so no bypass channel is needed for
this drainage area (0) The level spreader located in Drainage Area #2 is located 50' upslope of
a natural swale that is not a buffered stream therefore the bypass channel will not have any
buffer impacts associated with it
VIII. Mitigation
DWQ - In accordance with 15A NCAC 2H .0500, mitigation may be required by the NC
Division of Water Quality for projects involving greater than or equal to one acre of impacts to
Page 5 of 9
freshwater wetlands or greater than or equal to 150 linear feet of total impacts to perennial
streams:
USAGE - In accordance with the Final Notice of Issuance and Modification of Nationwide
Permits; published in the Federal Register on January 15; 2002, mitigation will be required when
necessary to ensure that adverse effects to the aquatic environment are minimal. Factors
including size and type of proposed impact and function and relative value of the impacted
aquatic resource will be considered in determining acceptability of appropriate and practicable
mitigation as proposed. Examples of mitigation that may be appropriate and practicable include,
but are not limited to: reducing the size of the project; establishing and maintaining wetland
and/or upland vegetated buffers to protect open waters such as streams; and replacing losses of
aquatic resource fimetions and values by creating, restoring, enhancing; or preserving similar
functions and values, preferable in the same watershed.
If mitigation is required for this project, a copy of the mitigation plan must be attached in order
for USACE or DWQ to consider the application complete for processing. Any application
lacking a required mitigation plan or NCEEP concurrence shall be placed on hold as incomplete.
An applicant may also choose to review the current guidelines for stream restoration in DWQ's
Draft Technical Guide for Stream Work in North Carolina, available at
http://h2o.eiir.state.nc.us/ncwetlands/strmgide,litml.
1. Provide a brief description of the proposed mitigation plan. The description should provide
as much information as possible; including; but not limited to: site location (attach directions
and/or map, if offsitc), affected stream and river basin, type and amount (acreage/linear feet)
of mitigation proposed (restoration, enhancement, creation, or preservation), a plan view,
preservation mechanism (e.g.; deed restrictions; conservation easement, etc.), and a
description of the current site conditions and proposed method of construction. Please attach
a separate sheet if more space is needed.
Because no impacts are proposed to jurisdictional waters, no stream or wetland mitigation is
proposed Additionally, the riparian buffer impacts proposed are considered "allowable"
therefore, no riparian buffer mitigation is proposed. Please see Section X.3 for details.
2. Mitigation may also be made by payment into the North Carolina Ecosystem Enhancement
Program (NCEEP). Please note it is the applicant's responsibility to contact the NCEEP at
[phone] to determine availability, and written approval from the NCEEP indicating
that they are will to accept payment for the mitigation must be attached to this form. For
additional information regarding the application process for the NCEEP, check the NCEEP
website at ham://h2o.enr state.ncusiwrp/index.htm. If use of the NCEEP is proposed, please
check the appropriate box on page five and provide the following information:
Amount of stream mitigation requested (linear feet): n/a
Amount of buffer mitigation requested (square feet): n/a
Amount of Riparian wetland mitigation requested (acres): n/a
Amount of Non-riparian wetland mitigation requested (acres): n/a
Amount of Coastal wetland mitigation requested (acres): n/a
Page 6 of 9
IX. Environmental Documentation (required byDWQ)
1. Does the project involve an expenditure of public (federal/state/local) funds or the use of
public (federal/state) land? Yes ? No
2. If yes, does the project require preparation of an environmental document pursuant to the
requirements of the National or North Carolina Environmental Policy Act (NEPA/SEPA)?
Note: If you are not sure whether a NEPA/SEPA document is required, call the SEPA
coordinator at [phone] to review current thresholds for environmental documentation.
Yes ? No ?
3. If yes, has the document review been finalized by the State Clearinghouse? If so, please
attach a copy of the NEPA or SEPA final approval letter. Yes ? No
X. Proposed Impacts on Riparian and Watershed Buffers (required by DWQ)
It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
required state and local buffers associated with the project. The applicant must also provide
justification for these impacts in Section VII above. All proposed impacts must be listed herein,
and must be clearly identifiable on the accompanying site plan. All buffers must be shown on a
map, whether or not impacts are proposed to the buffers. Correspondence from the DWQ
Regional Office may be included as appropriate. Photographs may also be included at the
applicant's discretion.
1. Will the project impact protected riparian buffers identified within 15A NCAC 2B 0233
(Meuse), 15A NCAC 2B .0259 (Tar-Pamlico), 15A NCAC 02B.0243 (Catawba) 15A NCAC
2B .0250 (Randleman Rules and Water Supply Buffer Requirements), or other (please
identify )? Yes J2?j No ?
2. If "yes", identify the square feet and acreage of impact to each zone of the riparian buffers.
If buffer mitigation is required calculate the required amount of mitigation by applying the
buffer multipliers.
Drainage Area #1
Zone* Impact (Temporary")
square feet Multiplier Required
Mitigation
1 389 N/A N/A
2 227(30) N/A N/A
Total 616(30) N/A
Drainage Area #4
Zone* Impact (Temporary**)
square feet Multiplier Required
Mitigation
1 387 N/A N/A
2 `4 - 83 (165) N/A -N/A
Total 470 (165) N/A
Page 7 of 9
Drainage Area #5
Zone* Impact (Temporary**) Multiplier Required
square feet Mitigation
1 647 N/A N/A
2 112 (213) N/A N/A
Total 759 (213) N/A
Drainage Area #6
Zone* Impact (Temporary**)
square feet Multiplier Required
Mitigation
1 851 N/A N/A
2 101 (167) N/A N/A
Total 952 (167) N/A
rain age Area #7
Zone* Impact (Temporary**)
square feet Multiplier Required
Miti ation
1 782 N/A N/A
2 188 (308) N/A N/A
Total 970 (308) N/A
Total
Zone* Impact (Temporary**)
square feet Multiplier Required
Mitigation
1 3056 N/A --NA
2 711 (883) N/A N/A
Total 3767 (883) N/A
* Zone 1 extends out 30 feet perpendicular from the top of thenear bank of channel; Zone 2 extends an
additional 20 feet from the edge of Zone 1:
** Temporary impacts will occur during construction of the bypass channels. All areas
impacted during construction will be stabilized and revegetated.
3. If buffer mitigation is required; please discuss what type of mitigation is proposed (i.e.,
Donation of Property, Riparian Buffer Restoration / Enhancement, or Payment into the
Riparian Buffer Restoration Fund). Please attach all appropriate information as identified
within 15A NCAC 213 ;0242 or .0244, or .0260. Riparian buffer impacts proposed are the
result of bypass channels required for level spreaders per the BMP Manual and should be
considered "allowable" therefore mitigation is not proposed
X1. Storrnwater (required by I WQ)
Describe impervious acreage (existing and proposed) versus total acreage on the site. Discuss
stormwater controls proposed in order to protect surface waters and wetlands downstream from
the property. If percent impervious surface exceeds 20%, please provide calculations
demonstrating total proposed impervious level. The overall planned impervious area for
Page 8 of 9
Taftwoods-Section 2 will be less than 15%specifically 14.6%. The proiect is located in
Johnston County and will have to adhere to the Johnston County Stonnwater ordinances.
Additionally, this project is located with Watershed Water Supply IV, NSW waters and subject
to Phase II Post-Construction requirements all DWQ delegated programs to Johnston County.
XII. Sewage Disposal (required by D WQ)
Clearly detail the ultimate treatment methods and disposition (non-discharge or discharge) of
wastewater generated from the proposed project, or available capacity of the subject facility.
The project will use individual septic systems.
X171. Violations (required by DWQ)
Is this site in violation of DWQ Wetland Rules (15A NCAC 2H .0500) or any Buffer Rules?
Yes ? No ?
Is this an after-the-fact permit application? Yes ? No
XIV, Cumulative Frupacts (required byDWQ)
Will this project (based on past and reasonably anticipated future impacts) result in additional
development, which could impact nearby downstream water quality? Yes El No
If yes, please submit a qualitative or quantitative cumulative impact analysis in accordance with
the most recent North Carolina Division of Water Quality policy posted on our website at
httpJ h2o.ennstatemc.us/newetlands. If no, please provide a short narrative description: The
proposed project does not require a 401 Water Quality Certification or Isolated Wetlands Permit,
therefore, according to the NCDWQ Draft Internal Policy, a qualitative or quantitative impact
analysis should not be required.
XV. Other Circumstances (Optional):
It is the applicant's responsibility to submit the application sufficiently in advance of desired
construction dates to allow processing time for these permits. However, an applicant may
choose to list constraints associated with construction or sequencing that may impose limits on
work schedules (e.g., draw-down schedules for lakes; dates associated with Endangered and
Threatened Species, accessibility problems, or other issues outside of the applicant's control).
n/a
t
gg ?f p
Applicant/Agent's Signature Date
(Agent's signature is valid only if an authorization letter from the applicant is provided.)
Page 9 of 9
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\NA Michael F. Easley,. Governor
William G. Ross: Jr., Secretary 3 North Carolina Department of Environment and Natural Resources
Coleen H. Sullins, Director
Division of Water Quality...........
October 15, 2007
DWQ Project # 07-1653
Johnston County
Mr. George Schleeht t.
_r
Lauraleen, LLG
3515 Queen Ann Drive
Clayton, NC 27527 a
Subject Property: Taftwoods East-Section 2
Ut to Mill Creek [030402,27-39, WSN, NSW]
Approval of 401 Water Quality Certification and Authorization Certificate per the Neuse River
Buffer Protection Rules (15A XCAC 2B.0233) with Additional Conditions
Dear Mr. Sclecht:
You have our approval, in accordance with the attached conditions and those listed below, to place fill
within or otherwise impact 258 linear feet of perennial stream and 11,686 square feet of Zone 1 Neuse
River basin protected riparian buffer, and 7,374 square feet of Zone 2 Neuse River basin protected
riparian buffer, as described in your application dated October 1, 2007, and received by the Division of
Water Quality (DWQ) on October 1; 2007, to construct a residential development. After reviewing your
application; we have decided that the impacts are covered by General Water Quality Certification
Number(s) 3631 (GC3631). The Certification(s) allows you to use Nationwide Permit(s) NW29 when
issued by the US Army Corps of Engineers (USACE). In addition, you should obtain or otherwise
comply with any other required federal, state or local permits before you go ahead with,your project
including (but not limited to) Erosion and Sediment Control, and Non-discharge regulations. Also, this
approval to proceed with your proposed impacts or to conduct impacts to waters as depleted in
your application shall expire upon expiration of the 404 or CAMA Permit,
This approval is for the purpose and design that you described in your application. If you change your
project, you must notify us and you may be required to send us a new application. If the property is sold,
the new owner must be given a copy of this Certification and approval letter and is thereby responsible for
complying with all conditions. If total fills for this project (now or in the future) exceed one acre of
wetland or 150 linear feet of stream, compensatory mitigation may be required as described in I SA
NCAC 2H .0506 (h). This approval requires you to follow the conditions listed in t11e attached'
certification and any additional conditions listed below.
The Additional Conditions of the Certification are:
1 Impacts Approved
The following impacts are hereby approved as long as all of the other specific and general
conditions of this Certification (or Isolated Wetland Permit) are meta No other impacts are
approved including incidental impacts:
W?cnne?ehhCarojina
401 Oversight/Express Review Permitting Unit r/VatllYa ly
1650 Mail Service: Center, Raleigh, North: Carolina 27699-1650
2321 Crabtree Boulevard; Suite 250; Raleigh; North Carolina 27604
. ::Phone. [phone] / FAX [phone] / Internet: httt??7/h2oenrstate.ncus[ncwetlands
Lauraleen, LLC
Page 2 of 5
October 15, 2007
Type of Impact Amount A lived Units Plan Location or Reference
Stream - perennial 258 linear feet) PCN 2 e 4 of 10
Buffers Zoned 11,686 (square ft. PCN age 7 of 1A
Buffers Zone 2 7,374 (square ft.) PCN page 7 of 10
2. No Waste, Spoil, Solids, or Fill of Any Kind
No waste, spoil, solids, or fill of any kind shall occur in wetlands; waters, or riparian areas beyond
the footprint of the impacts depicted in the Pre-Construction Notification. All construction
activities, including the design, installation, operation, and maintenance of sediment and erosion
control Best Management Practices, shall be pert'ormed so that no violations of state water,quality
standards, statutes, or rules occur,
3. Erosion and sediment control practices must be in full compliance with all specifications governing
the proper design, installation and operation and maintenance of such Best Management Practices in
order to protect surface waters standards:
a. The erosion and sediment control measures for the project must be designed, installed,
operated; and maintained in accordance with the most recent version of the North Carolina
Sediment and Erosion Control Planning and Design Manual.
b. The design, installation, operation, and maintenance of the sediment and erosion control
measures must be such that they equal, or exceed, the requirements specified in the most
recent version of the North Carolina Sediment and Erosion Control Manual. The devices
shall be maintained on all construction sites, borrow sites, and waste pile (spoil) projects,
including contractor-owned or leased borrow pits associated with the project.
c. Sufficient materials required for stabilization and/or repair of erosion control measures and
stormwater routing and treatment shall be on site at all times.
4. Sediment and Erosion Control Measures
Sediment and erosion control measures shall not be placed in wetlands or waters to the maximum
extent practicable. If placement of sediment and erosion control devices in wetlands and waters is
unavoidable, they shall be removed and the natural grade restored within six months of the. date that
the Division of Land Resources has released the project;
5. Culvert Installation
All work in or adjacent to stream waters shall be conducted in a dry work area. Approved BMP measures
from the most current version ofNCDOT Construction and Maintenance Activities manual
(http;//www.nedot.orp/d6h/operationsBMP manual/downloadBMP Manual.odfl::
such as sandbags, rock berms, cofferdams and other diversion structures shall be used to prevent
excavation in flowing water.
Culverts required for this project shall be installed in such a manner that the original stream profiles
are not altered. Existing stream dimensions (including the cross section dimensions, pattern; and
longitudinal profile) must be maintained above and below locations of each culvert. Culverts shall be
designed and installed to allow for aquatic life movement as well as to prevent head putting of the
streams. If any of the existing pipes are or become perched, the appropriate stream grade shall be re-
established or, if the pipes installed in a perched manner, the pipes shall be removed and re-hnstalled
correctly.
Lauraleen, LLC
Page 3 of 5
October 15, 2007
Culvert(s) shall not be installed in such ? manner that will cause aggradation or erosion of the stream up
or down stream of the culvert(s): Existing stream dimensions (including the cross section dimensions,
pattern and longitudinal profile) shall be maintained above and below locations of each culvert:
Therefore, you must provide plans with adequate details that indicate that the current stability of the
stream will be maintained or enhanced.. You must receive written approval from this Office for the
above plans before the culvert(s) is installed. Culvert(s) must be installed according to approved plans;
Placement of culverts and other structures in waters, streams, and wetlands must be placed below the
elevation of the streambed by one foot for all culverts with a diameter greater than 48 inches, and 20
percent of the culvert diameter for culverts having a diameter less than 48 inches, to allow low flow
passage of water and aquatic life. Design and placement of culverts and other structures including
temporary erosion control measures shall not be conducted in a manner that may result in dis:
equilibrium of wetlands or streambeds or banks, adjacent to or upstream and down stream of the
above structures. The applicant is required to provide evidence that the equilibrium shall be
maintained if requested in writing by DWQ.
The establishment of native, woody vegetation and other soft stream bank stabilization techniques
must be used where practicable instead of rip rap or other bank hardening methods. If rip-rap is
necessary; it shall not be placed in the stream bed, unless specifically approved by the Division of
Water Quality.
Installation of culverts in wetlands must ensure continuity of water movement and be designed to
adequately accommodate high water or flood conditions.
Upon completion of the project, the Applicant shall complete and return the enclosed "Certificate of
Completion" form to notify NCDWQ when all ,work included in the §401 Certification has been
completed. The responsible party shall complete the attached form and return it to :the 401/Wetlands
Unit of the NC Division of Water Quality upon completion of the project. Please send photographs
upstream and downstream of each culvert site to document correct installation along with the
Certificate of Completion form:
6. Protective Fencing
The outside buffer, wetland or water boundary and along the construction corridor within these
boundaries approved under this authorization shall be clearly marked with orange warning fencing
(or similar high visibility material) for the areas that have been approved to infringe within the
buffer, wetland or water prior to any land disturbing activities;
7. Compensatory Mitigation Using the Ecosystem Enhancement Program (EEP)
Mitigation must be provided for the proposed impacts as specified in the table below. We
understand that you wish to make a payment to the Wetlands Restoration Fund administered by
the NC Ecosystem Enhancement Program (EEP) to meet this mitigation requirement. This has
been determined by the DWQ to be a suitable method to meet the mitigation requirement. Until
the EEP receives and clears your check (made payable to: DENR - Ecosystem Enhancement
Program Office), no impacts specified in this Authorization Certificate shall occur. The EEP
should be contacted at [phone] if yop have any questions concerning payment into a
restoration fund. You have 60 calendar days from the date of this approval to make this
payment. For accounting purposes, this Authorization Certificate authorizes payrnent into
the Wetlands Restoration Fund to meet the following compensatory mitigation
requirement::::
Lauraleen, LLC
Page 4of5
October 15, 2007
Mitigation 8. Protective Fencing
The outside buffer, wetland or water boundary and along the construction corridor within these
boundaries approved under this authorization shall be clearly marked with orange' warning fencing
(or similar high visibility material) for the areas that have been approved to infringe within the
buffer, wetland or water prior to any land disturbing activities;
9; Certificate of Completion
Upon completion of all work approved within the 401 Water Quality Certification or applicable
Buffer Rules, and any subsequent modifications, the applicant is required to return the attached
certificate of completion to the 401 Oversight/Express Review Permitting Unit, North Carolina
Division of Water Quality, 1650 Mail Service Center, Raleigh, NC, 27699-1650.
Violations of any condition herein set forth may result in revocation of this Certification and may result in
criminal and/or civil penalties. The authorization to proceed with your proposed impacts or to conduct
impacts to waters as depicted in your application and as authorized by this Certification, shall expire upon
expiration of the 404 or CAMA Permit.
If you do not accept any of the conditions of this Certification (associated with the approved wetland or
stream impacts), you may ask for an adjudicatory hearing. You must act within 60 days of the date that
you receive this letter. To ask for a hearing; send a written petition, which conforms to Chapter 150B of
the North Carolina General Statutes to the Office of Administrative Hearings, 6714 Mail Service Center,
Raleigh, N.C. 27699-6714. This certification and its conditions are final and binding unless you ask for a
hearing.
Any disputes over determinations regarding this Authorization Certificate (associated with the approved
buffer impacts) shall be referred in writing to the Director for a decision. The Director's decision is
subject to review as provided in Articles 3 and 4 of G.S. 150B.
This letter completes the review of the Division of Water Quality under Section 401 of the Clean Water
Act and the Neuse riparian buffer protection rule as described within I SA NCAC 2B .0233. If you have
any questions, please telephone Cyndi Karoly or Ian McMillan at 919-733-1786.
Sincer >
6? Coleen H. Sullins, Director
Division of Water Quality
CHS/ijm
Enclosures: GC 3631
Certificate of Completion
NCDWQ 401 WQC Summary of Permanent Impacts and Mitigation Requirements
cc: USAGE Raleigh Regulatory Field Office
Lauren Witherspoon, DWQ Raleigh Regional Office
.............................................. .........................................................
T e of lm act Com ensatorv Re aired ' River and Sub-basin Number
: Stream - erennal 258 (feet Neuse/03020201
Lauraleen, LLC
Page 5 of S
October 15, 2007
DLR Raleigh Regional Office
File Copy
Central Files
Debbie Edwards,,S&EC, P.A., 11010 Raven Ridge Road, Raleigh, NC 27614
:::: :::: :::: :::: :::: :::: Filename:071fii8TaftwoodsEastSection2(lohnstonj40: `.?lBit:::: ::::
NNA Michael F. Easley, Governor
William G. Ross Jr, Secretary
North Carolina Department of Environment and Natural Resources
Coleen H. Sullins, Director
. Division of Water Quality
North Carolina Division of Water Quality
401 Water Quality Certification
Summary of Permitted Impacts and Mitigation Requirements
In accordance with 15A NCAC2H.0500, Mr. George Schlecht and Lauraleen; LLC, have permission to fill or
otherwise impact 258 linear feet of perennial stream and 11,686 square feet of Zone I Neuse River basin protected
riparian buffer, and 7,374 square feet of Zone 2 Neuse River basin protected riparian buffer, to construct the
proposed residential development at the site, which is located near Flowers, Johnston County, North Carolina. All
activities associated with these authorized impacts must be conducted with the conditions listed in the attached
Permit transmittal letter. TIES CERTIFICATION IS NOT VALID WITHOUT THE ATTACHMENTS.
.......................................................................................................
COMPENSATORY MITIGATION REQUIREMENTS, ECOSYSTEM ENHANCEMENT PROGRAM
DWQ PROJECT 2007165$
LOCATION: Flowers
COUNTY Johnston
BASIN/ SUB BASIN Neuse/03020201
As required by 15A NCAC 2H.0500, and the conditions of this Certification, you are required to compensate for
the above mitigable impacts through the restoration, creation, enhancement or preservation of wetlands, surface
waters and riparian buffers as outlined below prior to conducting any activities that impact or degrade the waters of
the state:
Note: Acreage requirements proposed to be mitigated through the Ecosystem Enhancement Program must be
rounded to one-quarter acre increments and linear foot requirements must be rounded up to the nearest
foot according to 15 2R.0503(b):
Impacts Mitigation
258 LinearFeet of Perennial Stream 258 Linear Feet of Perennial Stream
One of the options you have available to satisfy the compensatory mitigation requirement is through the payment of
a fee to the Wetlands Restoration Fund per NCAC 2R.0503. If you choose this option, please sign this form and
mail the form along with a copy of your 401 Certification or Buffer Approval to the Ecosystem Enhancement
Program at the address below. An invoice for the appropriate amount of payment will be sent to you upon receipt
of this form. PLEASE NOTE, THE ABOVE IMPACTS ARE NOT AUTHORIZED UNTIL YOU RECEIVE
NOTIFICATION THAT YOUR PAYMENT HAS BEEN PROCESSED BY THE ECOSYTEM ENHANCMENT
PROGRAM.
Signature Date
ECOSYSTEM ENHANCEMENT PROGRAM
1652 Mail Service Center
RALEIGH, N.C. 27699-1652
[phone]
Filename: 07165STaftwoodsEastSmtion2(Johnston)401_NBR_EEP
N,o°?EthCarolme
401 Oversight/Express Review Permitting Unit J/VlltlftYll?l,J
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North: Carolina. 27604
Phone[phone]/ Fax[phone]
:::: Internet, http://www.newaterquality.org
S i:t & Environmental ental onsulta ts, .'A
11010 Raven Ridge Road - Raleigh, North Carolina 27614 d: Phone: [phone] - Fax:: [phone]
www.SandEC.com
November 20, 2007
S&EC Project # 9197.W4
US Army Corps of Engineers
Attn: Mr. Thomas Brown
6508 Falls of the Neuse Rd., Ste. 120
Raleigh, NC 27615
RE: Notification of Statutory Status of Request for NWP ##29
Taftwoods East-Section 2
Clayton, Johnston County, North Carolina
Dear Mr. Brown:
On October 1, 2007, S&EC requested authorization from the US Army Corps of
Engineers (USAGE) to utilize Nationwide Permit (NWP) 29 to provide needed housing
to meet the growing demands for this area. The purpose of the road crossings is to
provide access to otherwise inaccessible portions of the property. Proposed impacts total
258 linear feet of perennial stream and no wetland impacts. At this time, 50 days have
lapsed since the US Army Corps of Engineer's receipt of the complete preconstruction
notification. To paraphrase the Federal Register (Vol. 67, No. 10, section 13.a,1), the
permittee may begin the proposed work if the USACE has not sent any written notices
(i.e. the permit itself or any notice of an incomplete submittal, etc.) within 45 days of the
District or Division Office of the USACE receiving the complete permit application
therefore, according to the aforementioned regulation the client may proceed with the
proposed activity as depicted in the submitted permit application and in compliance with
the NC-Division of Water Quality's 401-Approval.
Sincerely,
Debbie Edwards
Environmental Specialist
= Mr. George Schlecbt (Lauraleen, LLC)
Attachments
1, Copy of NWP General Conditions, Section 13
2. Copy of USACE signed receipt of the completed PCN application
Charlotte Office :::: :::: :: :::: :: :::: :::: :::: Greensb9 Office
236:LePhillip Court, Suite C :::: :::: :::: :::: :::: :::: :::: 3817-ELawndale Drive
Concord, NC 28025 Greensboro, NC 27455
Phone: [phone] Phone: [phone]
P.— 19nA% a0n_odn6:: Rw.::: MKfAn_401C

2090: Federal Register/Vol. 67, No.:10/Tuesday, January 15, 2002/Notices
management requirements). Another
important component of water quality : endspp.html and http://www.nfms.govl
prot_res/esahome.htmi respectivel written notice from the District or
Divisi
E
i

management is the establishment and
maintenance of vegetated buffers next to y.
12. Historic Properties. No activity
which may affect hi
t
i on
ng
neer; Subsequently,: the
permittee's right to proceed under the

open waters, including streams (refer to
General Condition: 19 for
vegetated s
or
c properties
listed, or eligible for listing, in the
N
ti
l NWP may be . modified, suspended, or
revoked only in accordance with the
.
buffer requirements for the NWPs). a
ona
Register of Historic Places is :.
authorized, until the District En
i procedure set forth in 33 CFR

This condition is only applicable to g
neer
has complied with the provisions of 33 330.5(d)(2).

projects that have the potential to affect
water quality. While a
propriate
CFR part 325, Appendix C. The :
pros
ecti
r (b) Contents of iNctification: The
notification must be in writing and
p
measures must be taken, in most cases p
ve pe
mittee must notify the
District Engineer if the authorized include the following informations
it is not necessary to conduct detailed
studies to identify such measures or to activity may affect any historic
properties listed, determined to be (1) Name, address and telephone
numbers of
prospective
ro
e
t
require monitoring.
10. Coastal Zone Management. In eligible, or which the prospective
permittee has reason to believe may be ed p
j
c
(3)
Location
on ri the proposed project;
o
ct{
u
ie
p
roposed
certain stafes, an individual state coastal eligible for listing on the National p
rpo
je
project; the pr
the
r
se;
purpo and
direct
zone management consistency
concurrence must be obtained or waived Register of Historic Places, and shall: not
begin the activity until notified by the o
s env
indirect
the prof ct would environmental effects
cause; any other
the project gio
(see Section 330.1(d)). District Engineer that the requirements a
N l
Regional General Permit(s); or
It. Endangered Species, (a) No

t of the National Historic Preservation Act ividtal Pe
be individual
s used or t
d to
e use
to
th
i

ac
ivity is authorized under anv NWP
which is likely to jeopardize the
continu
d
have been satisfied and that the activity
is authorized. Information on the
l
:
i of the
au
or
ze
any part d he:
proposed
activity.
Sketchketchs project be any
Sketches should b
r
id
wh
d
e
existence of a threatened or ocat
on and existence of historic w
e p
t
p
h
ov
e
en.
endangered. species or a species:
:.proposed for such designation; as resources can be obtained from the State
Historic Preservation Office and the a
t
e a
necessary to show that the activity
complies with the terms of the NWP
identified:under : the FederalEndangerd :NationalRegister:ofHistoricPlaces(see (Sketches

i
usually cl the p
rojectand
Species Act (ESA), or which will 33 CFR 330.4(8)). For activities that ma
may naqui
esult lt
when provided ded resu in a quicker
destroy or adversely modify the critical affect historic properties listed in, or decision J;
habitat of such species. Non-federal eligible for listing in, the National (4) For N
7, i2,
14,13, 21,
l
38,
permittees shall notify the District Register of Historic Places, the a
s
39, 41, 42,
the
and
PCN must also
Engineer if any listed species or : notification must state which historic : include a include delineation eat
nelineation of affected special
designated critical habitat might be property may be affected by the tal s
aes, including (ing wetlands,
affected or is in the vicinity of the proposed work or include a vicinity vege
ed
vegetated shallows (e.g., submerged

project, or is located in the designated
critical habitat and shall not begin work
map indicating the location of the
historic property. aquatic
vegetation; plexesss beds); and
riffle and pool complexes (see paragraph
on the activity until notified by the
District Engineer that the requirements
Distri
ne
h t the requi
m 13. ;Jotitcation.
(a) Timing; where required by the.:: 13fti):
(5) For NWP 7 (Outfall Structures and
of the
ESA h
eb
re
satisfied
that terms of the NWP, the prospective Maintenance), the PCN must include
the activity is authorized: For activities Permittee must notify the District information regarding the original
that mayaffect Federally-listed
that ma
ederal y: Engineer with a preconstruction design capacities and configurations of
enad orth
endangatened
species or notification (PCN) as early as possible. those areas of the facility where
designated critical
habitat
the The District Engineer must: determine. if maintenance dredging or excavation is
notification must
, the name(s) of
t inclu the notification is complete within 30 proposed;
the endangered
threatened species
re days of the date of receipt and can (6) For NWP 14 (Linear
that may be affected
the proposed
a
th
e
opos request additional information Transportation Crossings), the PCN
work
that utilize the
desigd
r
critical habitat that may be affected b
necessary to make the PGN complete
prospective
per
mt e
must include a compensatory mitigation
Proposo
offset porn
losses of
y
the proposed work. As a result of formal r
e does not provide all of f!
state
waters of the US and o statement
or informal consultation with the FWS then the
E ginee d Information,
?ct how
m losses
f
ll

or NMFS the District Engineer may add
species-specific regional endangered ootify e p
ospective
permittee
a
to notification is still waters o
the
US wil
be
d to
the maximum extent practicable;
species conditions to the NPVPs.
(b) Authorization of an activity by
y y a nd
in
complete
Will no co and the PCN review process
v
no
not commence
until all of the For NWP 21:( must Coal Mining
the PCN include
Activities),

NWP does not authorize the "take" of a
threatened or endangered species as
i
q
requested ct has been received
information
by the District EngSag{Weer. Tha ff
st
Office o of f Surface e Mining Mining
approved mitigation plan, , if if applicable,

defined under the ESA. In the absence prospective pormitteealia not beetn To be authorized by this NWP, the

of separate authorization (e.g.; an ESA
Section 10 Permit, a Biological Opinion the a ivi
1 nti notified in writing by the :
i District Engineer must determine that
the activity complies with the terms and

with "incidental take" provisions
etc
) D
strict Engineer that the activity may conditions of the NWP and that the
,
.
from the USFWS or the NMFS, both
lethal and non-lethal "takes" of proceed under the NWP with any
special conditions imposed by the adverse environmental effects are
minimal both individually and

protected species are in violation of the
ESA. Information on the location of District or Division Engineer; or
(2) If notified in writing by the District cumulatively and must notify the
project sponsor of this determination in

threatened and endangered species and
their critical habitat can be obtai
d or Division Engineer that an Individual
permit is required; 'or
: writing,
(6) For NWP 27: (Stream and Wetland
ne
directly from the offices of the USFWS (3) Unless 45 shave passed from
the Distri
t n5
d. ,'s Restoration), the PCN must include

and NMFS or their world wide web
pages at httpa1www,fws.gov1r9endspp1 gme"
receipt of the
c
completo "t{fication and the
pros
tive documentation of the prier condition of
the site that will be revelled by the
pec
permittee has not received permittee;
101
0 ate
PROGRAM..
September 26, 2007
George Schlecht
Lauraleen, LLC
3515 Queen Anne Drive
Clayton, NC 27527
Project: 'Paftwoods East County: JO STON
The purpose of this letter is to notify you that the North Carolina Ecosystem Enhancement Program (NCEEP) is willing to
accept payment for impacts associated with the above referenced project. Please note that this decision does not assure that
the payment will be approved by the permit issuing agencies as mitigation for project impacts. It is the responsibility of the
applicant to contact these agencies to determine if payment to the NCEEP will be approved.
This acceptance is valid for six months from the date of this letter and is not transferable. Uwe have not received a copy of
the issued 404 Permit/401 Cectification/CANA permit within this time frame, this acceptance will expire. It is the
applicant's responsibility to send copies of the permits to NCEEP. Once NCEEP receives a copy of the permit(s) an invoice
will be issued based on the required mitigation in that permit and payment must be made prior to conducting the authorized
work. The amount of the In Lieu Fee to be paid to NCEEP by an applicant is calculated based upon the Fee Schedule and
policies listed atwww.nceep.net.
Based on the information supplied by you the impacts that may require compensatory mitigation are summarized in the
followin table.
NEUSE
03020201 Stream (feet) Wetlands (acres) Buffer I
(Sq.FtJ Buffer Fl-
(Sq.Ft:)
Cold Cool Warm Riparian Non-Riparian Coastal Marsh
Impacts 0 0 258 0 0 0 0 0
Credits 0 0 1,056 0 0 0 0 0
Upon receipt of payment, EEP will take responsibility for providing the compensatory mitigation. If the regulatory agencies
require mitigation credits greater than indicated above, and the applicant wants NCEEP to be responsible for the additional
mitigation, the applicant will need to submit a mitigation request to NCEEP for approval prior to permit issuance. The
mitigation will be performed in accordance with the Memorandum of Understanding between the N. C. Department of
Environment and Natural Resources and the U. S. Army Corps of Engineers dated November 4, 1998.
If you have any questions or need additional information, please contact Kelly Williams at [phone].
Sincerely,
r
Wi ' in D. Gilmore,
irector
cc: CyndiKaroly, NCDWQ Wetlands/401 Unit
Thomas Brown, USACE-Raleigh
Lauren Witherspoon, NCDWQ-Raleigh
Debbie Edwards, agent
File
LIMA
kutor f ? t. qeg... Pro ig Oar Scat
EM
North Carolina Ecosystem Enhancement Program, 1652 Mall Service Center, Raleigh, MC 27699-1652 / 919-715-04761 w Av.nceep.net
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