20080162 Ver 1_More Info Received_20080313

ECS CAROLINAS, LLP
Ldp Geotechnical • Construction Materials • Environmental
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cue s
Ms. Sue Homewood
NCDENR, Division of Water Quality
585 Waughtown Street
Winston-Salem, North Carolina 27107
Reference: Permit Application -Additional Information Request
Approximate 7.7 Acre Tract -Highway 16
Wilkesboro, Wilkes County, North Carolina
ECS Project # G-14464
DWQ#09-0160 pg- o~ t, a/~d
Dear Ms. Homewood: I
March 12, 2008
!-° ~ ~~~~
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MAR, 1 3 20~$
~~3eFi4< '•P~AI'EF<GUAUTtl
~~,~=TIAP~!l3S a.NL SfCRAaWAfE~2 ~3FL4tJCN
ECS Carolinas, LLP (ECS) received a letter from the NC Division of Water Quality that indicates that the
above referenced application has been put on hold as incomplete (Letter Dated March 3, 2008). The
purpose of this letter and the attached information is to provide you with the requested information so that
the permitting process can proceed.
1. "Please submit documentation to justify the southern most (second) driveway and on NC
Highway 16 and parking area immediately adjacent to the driveway. The location of this
driveway requires stream impacts that it appears could be avoided with minimal changes to the
project layout."
The second driveway is the primary driveway that must be used for the proposed development. The first
driveway is an entrance only (not clarified in the initial application) and does not provide an exit from the
site to NC Highway 16. We've included a drawing with arrows showing the traffic direction into the site.
A school is located on adjacent property east of the site. The entrance to the school is the intersection of
NC Highway 16 and NC Highway 18. This intersection is extremely congested for two hours of the da
during the school year. As you will notice, both of the primary driveways are located as far from the
intersection, in the interest of safety and to avoid additional congestion. The secondary driveway located
closest to the intersection is an entrance only that will be used primarily by vehicles that will be dropping
off passengers at the site. They will still be required to exit onto NC Highway 16 or NC Highway 18,
depending on the direction they are driving. For the site to be suitable for its proposed use, the primary
driveways must remain in their current locations.
2. "Please provide a Stormwater Management Plan in accordance with requirements outlined on the
Division's website: htt ://h2o.enr.state.nc.us/ncwetlands/stormwater and a.html "
We've included as attachments the required stonnwater forms.
4811 Koger Boulevard • Greensboro, NC 27407 • [phone] • Fax [phone]

f
Response to Request for Additional Information
Wilkesboro, North Carolina
ECS Project 09-14464
March 12, 2008
Please contact us at [phone] if you have any questions concerning this permit application or if
there is a need for additional information.
Sincerely,
ECS CaROLiNas, LLP
Michael T. Brame
Senior Environmental Scientist
cc: Ian McMillan
2

Permit Number:
(to be provided by DWQ)
Drainage Area Number: ~
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 ^ 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, the plants on the
vegetated shelf and perimeter of the basin 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 plants on the vegetated 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 m;n;m;zed 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 roblem:
The entire BMP Trash/debris is resent. 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 a lication.
Vegetation is too short or too Maintain vegetation at a height of
lon a roximatel six inches.
Form SW401-Wet Detention Basin I&M-Rev.2

Permit Number:
(to be provided by DWQ)
Drainage Area Number:
BMP element:
The embankment Potential roblem:
Shrubs have started to
row How I will remediate the roblem:
R
g emove 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 re air.
The outlet device Clogging has occurred. Clean out the outlet device. Dispose
of the sediment off-site.

The receivin
wate The outlet device is dama ed Re air or re lace the outlet device.
g
r Erosion or other signs of Contact the l
l NC
oca
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 ~ feet in the main pond, the
sediment shall be removed.
When the permanent pool depth reads ~ feet in the forebay, the sediment
shall be removed.
Sediment Removal
Bottom
BASIN DIAGRAM
BIZ in the blanks)
p Permanent Pool Elevation {E~,'
~~ "~~ ` Pe anen Pool ~
' - - - - - - - - - - - - - - - - - Volume Sediment Removal Elevation- " `~ ~~~
~A~9.~` -ft Min. --------------------- I-.. --- -------~
Sediment Bottom Elevation ~'' ~~"'~~ `~ "~'
Storage
FOREBAY MAIN POND
Volume
1-ft
Storage
Form SW401-Wet Detention Basin I&M-Rev.2

MAR-11-2008 TUE 10 20 AM Carolina Realty Incorp FAX N0. 13368381988
ainlt. i. 1UUd 3: h9NM ECS N0.311 i P. 4/~
Permit Numbor:
(fo 6eprovlded byDWQ)
I acb~owlodge and egroe by my si®natuco balaw that. I em responsible for zhe
perForrnrotee of the maiatmartoc procedures listed ebova I agree to notify DWQ of say
problems with. tl~ system ar prior to my ehartges to the system or responsible party.
Projocrname: IRa /"L''I~~~ '~~'~iR~T~~
B.l~" drainage area riamber: „~
P. 02
PriAt name: ~ ~
'Title: Gv~7/E ~
e Arlr.re• I ~ ~b f_it rdf1/i~2 ~. Cff ~l /~ /eo~9 n , U/ C lCf16D ~eo~li~ C - ~~9 ~
- ~/~ ~.~ ~ X36 ' / ~~{ .. /Ol / / cc //
Signature;
Date:~~~ d ~'
Note: 7be 1t~xUy reapor<siblc pally ~QUId Hat be a hameownets aaaocietian unlosa aioro t4aa SO% of
the lot+ have boon sold and a residoAt of the subdi'viaion Das been Hamad Ne prealdegt,
~, Gt opine ~ , ~ ie ~ ~rnu`1, a I~Iotary Public for the State of
e S County of D~. ~Cc/0/In do hereby certify that
~Q.. _ ~~eV s personslly appaazcd befoxd the this
day of 1~i4/QL~ ~ ~ ~, and acknowledge the due execution of the
forgoing wvt detention basin maintenennae requireimants. Wittuss my band sad official
seal,
..._--- -
NADINE A. l,lE6ERMA
NOTARY PU9LIC
WILKES COUNTY, NC
u Commission Expires; 811,___ ~_~~
sn~
My oommissioa expires v ~ ~D/'~
GZC~K-e-
Form SW40t•Wet Dotention Basta l~M-Rev,Z

Permit No.
(to be provided by DWQ)
lll. REQUIRED 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.
?~1.,~,` ':`, ~`~ ~ 1. Plans (1" - 50' or larger) of the entire site showing:
- Design at ultimate build-out,
- Off-site drainage (if applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
-Basin dimensions,
-Pretreatment system,
- High flow bypass system,
-Maintenance access,
~~- -~ ~~ ~~ ``.l~ecot'~ed drainage easement and public right of way (ROV1~,
~ ._., .
- Overflow device, and
-Boundaries of drainage easement.
,.~9' u ~ (~'~~ 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing;
-Outlet structure with trash rack or similar,
-Maintenance access,
-Permanent pool dimensions,
-Forebay and main pond with hardened emergency spillway,
-Basin cross-section,
-Vegetation specification for planting shelf, and
-Filter strip.
:-~~~! ~..-. ~`'`~~ 3. Section view of the dry detention basin (1" = 20' or larger) showing:
- Side slopes, 3:1 or lower,
-Pretreatment and treatment areas, and
-Inlet and outlet structures.
' } .~ ~ ~~` 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
y ~...a., -..,,`
~j~_~ '' g' ' 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for Forebay,
to verify volume provided.
-~ ~-'~ 6. 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.
7. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
~. ? 8. The supporting calculations.
' •~ ~_ ~ ~ ~ 9. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
. _ •~'
10. A copy of the deed restriction.
Form SW401-Wet Detention Basin-Rev.1 Part III. Required Items Checklist, Page 1 of 1

Permit No.
(to be provided by DWQ)
~ OF W A T~9
~ ~
}
~
NCDENR y
~`
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information.
I. PROJECT INFORMATION
Project name
Contact person
Phone number
Date
Drainage area number
II. DESIGN INFORMATION
Site Characteristics
Drainage area ~ ftZ
Impervious area ~ -"' '- 7 y " ftZ
impervious ~ p
Design rainfall depth I in
Storage Volume: Non-SR Waters
Minimum volume required •~ ~~ ft3
Volume provided ft3
Storage Volume: SR Waters /,
~ ; :k
1-yr, 24-hr runoff depth in
Pre-development 1-yr, 24-hr runoff _
__ _ °3
Post-development 1-yr, 24-hr runoff _
___ft3
Minimum volume required _
_
ft3
Volume provided ft3
Peak Flow Calculations
Is pre/post control of the 1-yr 24-hr peak flow required? (Y or N)
~
^
1-yr, 24-hr rainfall depth in
~
Rational C, pre-development (unitless)
Rational C, post-development ___.__(unitless)
Rainfall intensity:1-yr, 24-hr storm inlhr
Pre-development 1-yr, 24-hr peak flow - ft3/sec
Post-development 1-yr, 24-hr peak flow ft3lsec
Pre/Post 1-yr, 24-hr peak flow control ft3lsec
Basin Elevations
Basin bottom elevation ~ 1 ? ~ • ft
Sediment cleanout elevation ft
Bottom of shelf elevation ft
Permanent pool elevation '.. t ?' . _: ft
Top of shelf elevation ~ ~, '. , ' ft
Temporary pool elevation ft
Volume and Surface Area Calculations
SAIDA ratio , , (unitless)
Surface area at the bottom of shelf J i ter.' ftZ
Volume at the bottom of shelf ! =1 ft3
Permanent pool, surface area required ftZ
Permanent pool, surface area provided ftZ
Permanent pool volume - ft3
Average depth for SAIDA tables __~ ft
Surface area at the to of shelf
P I Z
) _____ ft
Volume at the top of shelf ft3
Form SW401-Wet Detention Basin-Rev.3 Parts I. & II. Design Summary, Page 1 of 2

Permit No
(to be provided by DWQ)
III DESIGN INFORMATION I
Forebay volume ft3
Forebay % of permanent pool volume /S
Temporary pool, surface area provided `r ft2
Drawdown Calculations ~,
Treatment volume drawdown time days
Treatment volume discharge rate ~ ft31s
Pre-development 1-yr, 24-hr discharge - ft31s
Post-development 1-yr, 24-hr discharge ft3/s
Additional Information
Diameter of orifice in
Design TSS removal
Basin side slopes :1
Vegetated shelf slope ~~ ~ 1
Vegetated shelf width ft
Length of flowpath to width ratio ~ ~ 1
Length to width ratio `~~ .= :1
Trash rack for overflow & orifice? ~ (Y or N)
Freeboard provided ~ ft
Vegetated filter provided? (Y or N)
Recorded drainage easement provided? (Y or N) C ~~ ra r''ti °- ~: ~ }
Capures all runoff at ultimate build-out? { (Y or N)
Drain mechanism for maintenance or emergencies
Form SW401-Wet Detention Basin-Rev.3 Parts I. & II. Design Summary, Page 2 of 2

CAVANAUGH
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WWW.CAVANAIJGHSCLLITIaNS.COM

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PERMANENT WET DETENTION POND DESIGN - RISER/BARREL
Revised 109-2008
WILKES COUNTY
PROJECT: Ira Myers INDEX NO: 11,07.067
CHECKED BY:
LOCATION: NC 16 & NC 18 IN WILKES COUNTY DATE: January 09,2008
REVISED:
TOTAI SITE AREA =
PROPOSED BUILT UPON AREA =
FUTURE BUILT UPON AREA =
TOTAL ON-SITE BUILT UPON AREA =
PERCENT BUILT-UPON =
ON-SITE DRAINAGE AREA TO POND =
ON-SITE BUA TO POND =
)NSITE %BUA FOR POND SUB-BASIN =
OFF-SITE DRAINAGE AREA TO POND =
TOTAL WATERSHED AREA TO POND =
bISTURBED AREA =
WATERSHED =Yadkin River
CLASSIFICATION : WS - C
(GWAIWCA} = GWA
7.72
6.95
0.00
6.95
90.03%
7.50
6.95
92.67%
0,00 MAX. OFF-SITE B.U.% = 25%
7.50
7.00
PERMANENT SEDIMENT STORAGE
PERMANENT WATER QUALITY
COMPOSITE B.U. % _
DEPTH {minimum 3 feet)
SAlDA (Figure 5.6.2)
TEMPORARY WATER QUALITY
PRINCIPAL SPILLWAY
TYPE
DESIGN STORM
RAINFALL INTENSITY
RUNOFF COEFFICIENT
EMERGENCY SPILLWAY
TYPE
DESIGN STORM
RAINFALL INTENSITY
RUNOFF COEFFICIENT
POND DATA
ELEV. @ BOT. OF POND = 1125.5
ELEV.@ BOT. OF PSS = 1125.5
ELEV. @ BOT. OF PWQ = 1127
ELEV. (aZ NORMAL POOL = 1131
ELEV. @ TOP. OF RISER = 1133
ELEV. @ EMER, SPILLWAY = 1133.5
ELEV, @ TOP OF DAM = 1134.5
INVERT OF BARREL = 1125,5
0.5 acre-inch per disturbed acre
0.125 acre-In per total drainage area
92.67 percent
6.0 feet
3.1 percent
1.O rainfall to be controlled
corrugated aluminum
X reinforced concrete
10 year
5.46 inches per hour
0.9
X grass lined
rip-rap lined
100 year
7.32 inches per hour
0.9
SURFACE AREA = 260D
SURFACE AREA = 2600
SURFACE AREA = 3614
SURFACE AREA = 10455
SURFACE AREA = 14240
(ELEV. @ BOT. OF POND= 1125.50 SURFACE AREA = 2600
ELEV. @ NORMAL POOL = 1131.00 SURFACE AREA = 10455
ALLOW 75% OF BASIN VOLUME TO WQ ORIFICE _

ELEV. @ BOT. OF PSS = 1125.50 SURFACE AREA = 26D0
ELEV. @ BOT. OF PWQ = 1127.00 SURFACE AREA = 3614
VOLUME PROVIDED =
'ERNiANENT WATER QUALITY SURFACE AREA REVD 1012!
NORMAL POOL ELEVATION = 1131.0
SURFACE AREA PROVIDED = 1045
Ol
REQUIRED
Rv= 0.884
VOLUME REQUIRED = 24067
ELEV. @ BOT. OF 7W0 = 1131.00 SURFACE AREA = 10455
ELEV. @ TOP OF TWQ = 1133.00 SURFACE AREA = 14240
VOLUME PROVIDED =
DESIGN STORM PEAK FLOW =
HEAD ABOVE TOP OF R1SER =
ELEVATION AT TOP OF RISER = `'D'tl
0.50
1133,00
BARREL: BARREL SIZE USED (in) = 15.00
ELEVATION AT TOP OF RISER = 1133.00
ELEVATION OF BARREL INVERT = 1125.5
RISER: RiSER(AREA) =1.5 TIMES AREA OF. 15.00
MIN. RISER DIA. = 18.37
RISER DIA,USED = 48
VATER QUALITY RELEASE HOLE
ELEV, @ BOT. Of WATER QUALITY RELEASE HOLE = 1131.Oi
flAXIMUM RELEASE RATE _ '
AINIMUM RELEASE RATE _
AAXIMUM HOLE SIZE = 0.03554112 2.5
AINIMUM HOLE SIZE = 0.014216448 1.6
!, @ TOP OF RISER = 1133.00
!, (m' BOT. OF PSS = 1125.50
50
7
H = ,
AREA OF R1SER = 12.6
VOLUME OF RISER = 94'2
AREA OF BARREL = 1.2
EXPOSED LENGTH 10.00
VOLUME OF BARREL = 12.3
WEIGHT OF WATER DISPLACED = 6646.82
FACTOR OF SAFETY (10%) 7311,51
OLUME OF CONCRETE ANCHOR = 83'6

Table of Contents
Hydraflow Nydrographs by Intelisolve
Ira Myers FiNAl.gpw
Friday, Jan 11 2008, 10:10 AM
Hydrograph Return Period Recap ...................................................................... 1
10 -Year
. 2
Summary Report .................................
.............................................. .................................
3
...............................................
orts
h R ..................................
..........................
ep
Hydrograp 3
...................
stormwater
voir
2
R ..................................
...................
,
eser
,
Hydrograph No. 4
..........................
rt . ...................................
.
..................................................
Pond Repo
100 -Year
5
............................. ...................................
Summary Report ....... .. 6
orts ........................................
h R
d .................................
ep
rograp
Hy 6
Hydrograph No. 2, Reservoir, stormwater ..................................... ...................................
.........................
t ................................... 7
.....................................................
Pond Repor

nywauvw nyu~~yiaN~~~ ~r ......~......
Hydrograph Return Period Recap

nyu~ai wrr ~ ~r~~~y.aN..~.,~ .............._
Hydrograph Summary Report

3 I
Hydrograph Plot
Hydraflow Hydrographs by Intellsolve Friday, Jan 11 2008, 10:10 AM
Hyd. No. 2
starmwater
Hydrograph type =Reservoir Peak discharge = 0.14 cfs
Storm frequency = 10 yrs Time interval = 1 min
Inflow hyd. Na. = 1 Max. Elevation = 1132.84 ft
Reservoir name =detention Max. Storage = 23,059 cult
Storage Indication method used.'
Q {cfs)
40.00
30.00
20.00
10.00
0 00
Hydrograph Volume = 17,819 cult
stormwater
Flyd. No, 2 --10 Yr
A I_~ _ ~-i_ i _TI
i
Q (cfs)
40.00
30.00
20.00
10.00
0.00
0 5 10 15 19 24 29 34 39 44 48
Time (hrs}
Hyd No. 2 Hyd No. 1

Pond Report
Hydraffow Hydrographs by lntelisolve Friday, Jan 11 2008, 10:10 AM
Pend No. 1 -detention
Pond Data
Pond storage is based on known contour areas. Av erage end area me#hod used.
Stage !Storage Table
Stage (ft) Elevation (ft} Contour area (sgft} Incr. Storage {tuft) Total storage (cult)
0.00 1131.00
00 1132.00
1 10,455
12,825 0 0
11,640 11,640
.
00 1133.00
2 14,241 13,533 25,173
.
00 1134,00
3 15,729 14,985 40,158
.
3,50 1134.50 16,500 6,057 46,215
Culvert /Orifice Structures Weir Structures
CA] [B] [C] [D] [A] [B] [Cl ID]
Rise {in) = 15.00 2.00 0,40 0.00 Crest Len {ft) = 4.00 10.00 0.00 0.00
Span {in) = 15.00 2.00 0,00 0.00 Crest EI. {ft) = 1133.00 1133.50 0.00 0.00
No. Barrels = 1 1 0 0 Weir Coeff. = 3.33 3.33 0.00 0.00
Invert EI. {ft) = 1127.00 1131 .00 0.00 0.00 Weir Type =Riser Rect --- •--
Length (ft) = 10.00 0.00 0,00 0.00 Multi-Stage =Yes No No No
Slope (%) = 0.30 0.00 0,00 0.00
N-Value = .013 .013 .000 .000
O 'f C ff = 0 60 0 60 0.00 0.00
rl . oe .
Multi-Stage = nla Yes No No Exfiitration = 0.000 inlhr (Contour) Tailwater Elev. = 0.00 ft
iJola: CulvarUOrifice outRows have bean analyzed under inlet and outlet control.
Stage (ft)
4.00
3.00
2.00
1.40
0.00
0.00 5.00
Total Q
Stage !Discharge
Stage (ft)
4.00
3.00
2.00
1.00
0,00
10.00 15.60 20.00 25.00 30.00 35.00 au.uu 4a,uu vu.vb
Discharge (cfs)
4

Hydrograph Summary Report

Hydrograph Plot
Hydrafiow Hydrographs by Intelisoive
Hyd. No. 2
stormwater
Hydrograph type =Reservoir
Storm frequency = 100 yrs
Inflow hyd. No. = 1
Reservoir name =detention
Friday, Jan 11 2008, 10;10 AM
Peak discharge = 3.10 cfs
Time interval = 1 min
Max. Elevation = 1133.36 ft
Max. Storage = 30,621 cult
Storage Indication method used,
Hydrograph Volume = 24,512 cuff
stormwater
Q (cfs} Q (cfs)
Hyd. No. 2 -- 100 Yr
0
60.00
50.00
40,00
30.00
20.00
10.00
0 00
50.0
50.00
40,00
30.00
2a.oo
10.00
0,00
6 I
0 5 10 15 19 24 29 34 39 44 4t5
Time (hrs}
Hyd No. 2 Hyd No. 1

Pond Report
Hydraflow Hydrographs by Intefisolve Friday, Jan 11 2008, 10;10 AM
Pond No. 1 -detention
Pond Data
Pond storage is based an known contour areas. Average end area method used.
Stage 1 Storage Table
Stage (ft} Elevation (ft) Contour area (sgft} Incr. Storage (tuft) Total storage {tuft)
0,00 1131.00
00 1132.00
1 10,455
12,825 0
11,640 0
11,640
.
00 1133.00
2 14,241 13,533 25,173
,
00 1134.00
3 15,728 14,985 40,158
.
3.50 1134.50 16,500 8,057 48,215
Culvert 1 Orifice Structures
CA] [g] [~] CDl
Rise (in) = 15.00 2.00 0.00 O,DO
Span {in) = 15.00 2.00 0.00 0,00
No. Barrels = 1 1 0 0
invert EI. {ft) = 1127.00 1131.00 0.00 0.00
Length (ft) = 10.00 0.00 0.00 0.00
Slope (%) = 0.30 0.00 0.00 0.00
N-Value = .013 .013 .000 .000
Orif. Coeff. = 0.60 0.60 0.00 0.00
Multi-Stage = n/a Yes No No
Weir Structures
[Al [Bl IC] [D]
Crest Len (ft) = 4.00 10.00 0.00 0.00
Crest EI. (ft) = 1133.00 1133.50 0.00 0,00
We[r Coeff. = 3.33 3.33 0.00 0.00
Weir Type =Riser Rect --- ---
Multi-Stage =Yes No No No
Exfiltratlon = 0.000 inlhr (Contour) Tailwater Elev. = 0.00 ft
Note: CulverUOrifice outflows have baen analyzed under inlet and oupet control.
Stage (ft)
4,00
3.00
2;aD
1.00
0.00
0.00 5.00
Total Q
Stage t Discharge
SEage (ft)
4.00
3.00
2A0
1.00
O.OD
10.00 15.00 20.00 25.00 30.00 35.00 40,00 45.uu nu.u0
Discharge {cfs)
7

Notes: For Multipie Culverts use 1.25 times diameter of pipe
For Outlets on slopes greater Phan 10% use next higher equation number
If "Special" appreas in the results box, another method should be used for design
NC DOT Rip-Rap sizes used (T=1.5*Dmax}

Appendices
N]GW YORK DOT DTSSIPATOR METHOD
rOR USE I]V DEI:INED CI{ANNELS
(Sotu'ce: "Bank and channel lining procedures", New Yoffie Department
of Transportation, Division aF Design and Construction, 1971.)
Note: To use the fol3owing chart you must lenow:
(1) Q full capacity
(2) Qto
(3} V full
(4) Vta
where Q =discharge in cfs and V =Velocity in FPS.
F,STIMATIU]V OF STONE SIZE ANA DIMENSIONS FUR
CULVERT APRONS
Step 1) Compute Flow velocity Vo at culvert or paved channel outlet.
Step 2) Far pipe culverts Do is diameter.
For pipe arch, arch and box culverts, and paved channel outlets,
Do--Ao, where A.~ cross-sectional area of flow at outlet.
For multiple cu]verts, use Do=1,2.5xDo of single culvert.
Step 3) Far apron grades of lt7% or steeper, use recommendations
For next higher•zone, (Zones 1 through C}.
25
20
N 1E
a
~_
U
O ~~
0' S' 10' i r ~„
DIAMETER (Ft.)
Figure 8.UGb.1
r
i
8.Ob.5
t'Lcv. 123

0
APRON MATERIAL rHOr~cr cuvaRr ro rpEVertr scoUR
HOLE USE l2 ALWAYS
~j Lz
3TONE FILLING (F{NE} CL A 3 x Do 4 x Da
STONE FILLING (LIGHT) CL. B 3 X Do B X Do f
STONE FILLING (MEDIUM) CL.1 4 x Do 8 x Do
STONE F1t.LlNG (HEAVY) CL,1 4 x Do 0 x Do
STONE. FILLING (HEAVYI CL 2 5 x Do 10 x Do
S70NE FILLING (HEAVYI CL, 2 6 x Do 10 x Do
R+aY DISSIPATpRS, S7lLLING
~O
E
I
L
LA
O
NE).
S
IZ
FIGER S
Ra~IN
o
R
Fig. 8.06.b,2
Width = 3 timrs pipe dia. (tninJ
DE'1'ERMINATIDN OF STONE SIXES FOR DUMPEII STOKE
CKANNEL LININGS 'AND REVETMENTS
Step 1) tlse figure 8.U6.b.3 to determine maximum stone size (e.g. for 12
Fps=20" or SSO lbs.
Step 2) Use figure 8.06.b.4 to determine acceptable size rflnge for stone
(for 12 FPS it is 125-5001bs, for 75% of stone, and the maximum
and minimum range in weight should be 25-5001bs,)
Nate: In determining channel velocities for stone Linings and revetment, use
the following coefficients of roughness:
Diarrteter Mannin's M~• thiclQ-ess
(inches} "n" of lining (inches
Fine ~ 3 0,031 9 12
Light 6 0.035 12 18
Medium 13 0.040 18 ~'
Heavy 23 0.044 30 36
(Channels) (L3issapatara)
s.a6.6
Rev. 1?/93

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