20151048 Ver 1_Sill and Baffle Design_20151226

Carpenter,Kristi
From:Davis, Mark S
Sent:Monday, October 26, 2015 2:00 PM
To:'Lori Beckwith ([e-mail])'; Chapman, Amy; Carpenter,Kristi;
Barnett, Kevin; Jason Mays ([e-mail]); Chambers, Marla J
Cc:Deyton, Joshua B; Hill, Mark E
Subject:Bridge No. 107 on SR 1214 over Mountain Creek - Graham County - Sill and Baffle
Design
Attachments:Bridge No. 107 - Graham County - Bridge to Culvert Avoidance and Minimization
Form.pdf; Bridge No. 107 - Graham County - Sill and Baffle Design.pdf
Follow Up Flag:Follow up
Flag Status:Flagged
Ladies and Gentlemen,

Attached is the correct sill and baffle design for the subject bridge NW 14 permit application I submitted on
10/6/15. Please disregard “Detail D” on Plan Sheet 4. The Culvert Survey and Hydraulic Report (page 5) is correct. I
have also attached the Bridge to Culvert Avoidance and Minimization Form for your information. If you have any
questions, please advise.

Thanks, Mark

Mark S. Davis

Environmental Supervisor

NCDOT/Division 14 Office

828 586 2141 office

282 508 9670 mobile

[e-mail]

253 Webster Road

Sylva, NC 28779

Email correspondence to and from this address is subject to the

North Carolina Public Records Law and may be disclosed to third parties.

Email correspondence to and from this sender is subject to the N.C. Public Records Law and may be disclosed to third parties.
1

I Ii�;E71�'�]V North Carolina Department of Transportation � �
:�iiUl`1]�1�1i�t1t('C I
„�- .- Highway Stormwater Program �;'
STORMWATER MANAGEMENT PLAN —'��
(Version 2.02; Released April 2015) FOR NCDOT PROJECTS
WBS Element: 17.BP.14. TIP No.: R.90 County(ies): Graham Page 2 of 2
Bridge to Culvert Avoidance and Minimization
Proposed Structure Summary
Sheet No. & Station Sheet No.: 4 Station: 12+66.58 Number of Culverts: 1
Drainage Area (ac or sq mi): 2.8 Sq. Miles Culvert Width/Diameter (ft : 12
Surface Water Body: 1 Mountain Creek Culvert Height (ft): 4
Culvert T e: Reinforced Concrete Box Culvert Culvert Length ft 69
Avoidance and Minimization Efforts: The length of the culvert was minized to the maximum extent possible given the curve of the roadway and the skew of the stream.
(Bridge to Culvert)
Stream Slope Fish and/or Aquatic Life Passage
Existing Average Stream Slope (°/a): 2.69 % Existing Low Flow Channel Dimensions 10' to 12'
Proposed Culvert Slope (%): 2.�� % in the Stream:
Culvert Burial
Proposed Culvert Burial Depth (ft): 1.5
Existing Streambed Material: sand, gravel with medium boulders Proposed Low Flow Dimensions Low flow sill is in the center of the culvert. The
Through the Culvert: low flow sill is 8' wide.
Proposed Sills/Baffles: A low flow sill is created through the center of the
culvert. This low flow sill is 0.5' lower than the high Existing Low Flow Velocities in the
flow sill. Stream (ft/s): 7'6
ropose ow ow e oci ies roug
the Culvert (fUs): 9'�
Alternating Low Flow Sills/Baffles: The low flow sill is in the center of the culvert
all the way through the culvert. The sill does
not alternate through the culvert.
Culvert/Stream Alignment
Stream Patterns Upstream and Downstream The stream is relatively shallow in normal flow conditions and rocking which may prevent spme fish passage during normal flow.
of the Culvert that Could Affect Fish
Passage and Bank Stability:
Bed Forms Impacted by Culvert (riffles, a small riffle
pools, glides, etc.):
Low Flow Floodplain Bench Required? No No floodplain bench is provided
(provide justification)
Sharp Bends at Inlet/Outlet? No There is a bend (not sharp) just upstream of the inlet of the culvert. The culvert has been placed in alignment with the existing
(describe culvert alignment with stream) stream so that existing flow patterns are maintained.
Stream Realignment Necessary? (provide No The culvert is aligned with the direction of flow in the stream therefore no stream realignment is necessary.
justification)
Bank Stabilization: The only bank stabilization required is riprap at the headwalls of the inlet and outlet of the culvert.
Outlet Velocities
Natural Stream Channel 2-yr Velocity (ft/s): 7.6 Natural Stream Channel 10-yr Velocity (ft/s): 9.6
Proposed Culvert 2-yr Outlet Velocity (ft/s): 9.1 Proposed Culvert 10-yr Outlet Velocity (ft/s): 10.4
Roadway Geometric Considerations
Evaluate/Describe Roadway Geometric Constraints:
The roadway is on a curve at the location of the proposed culvert as well as the stream is not perpendicular to the roadway. This creates a longer culvert than would be necessary if the roadway
was straight and the stream was perpendicular to the roadway.

�
�PAM1N 6Y :
NOTES
NATIVE IAATERIAL EXCA4ATE0 FROIA THE EXISTING STREAIA BE�
OR FLOOD PLdIN AT THE PROJECT SITE DURING CULVERT
CONSTRUCTION SHALL BE STOCKPILED AND LATER PLACE� IN
THE PROPOSE� CU�VERT BETYIEEN SILLS TO PROVIOE A CONTINll0U5
LOW R01Y CHANNEL NATIVE IdATERIAL IS Sl1BJECT TO APPROVAL
BY THE ENGINEER AND IAAY BE SUBJELT TO PERlAIT LONDIiI0N5.
THE STOCKPILED NATIVE IdATERIAL SHALL BE PLACE� AS SHOWN
IN THE °PLAN OF FLOOR SILL LAYOUT° SKETCH TO PROVIDE A 1'-6"
DEPTH LOYI FLOW CHANNEL BETYIEEN LOYV FLOW SILLS. AND SHALL
BE PLACED TO THE DEPTH OF 2'-0"BETWEEN HICH F1.01'I SILL.
SUPPLEIAENTAL STONE OF $IhIILAR CHARACTERISTICS OF THE NATIVE
lAATERIAL IAAYBE USED AS NECESSARY IYITH APPROVAL BY ENGINEER.
TNE ENTIRE COST OF WORK REOIIIRED TO PLACE THE EXCAVATE�
MATERIAL SHALL BE INCLUDEO IN THE CONTRACT LUMP SUlA
PRICE BID fOR CULVERT EXCAVATION.
THE ENTIRE COST OF WOFK REOUIRE� TO CONSTRl1CT THE SILL$
SHALL BE INCLUDED IN THE VCRIOl15 PAY ITEMS.
TOP OF LOYI FLOW SILLS SHOULD lAATCH STREAlA BED ELEVATION
IN LOW FLOYI CHCNNEL OF STREAld.ITHALWECI
DO NOT SET ELEVATION OF HIGH SILL ABOVE BANK FULL.
NlllABER OF SILLS DETERA4NED BY THE ENCINEER.
ELEVATION
LOOKING 001'INSTREAlA
��
�1
STAGE 1 QUANTITIES
CLASS A WNCRETE
BARREL c�i I.I926 CY/FT 30.8 LY
WINGS, ETC. T.T CY
SILLS 1.5 LY
TOTAL 40.0 C7
REINFORCINC STEEI.
BARREL & SILLS 6 639 LBS.
VYINGS,ETC. 322 �BS.
TOTAL 6.956 185.
CULVERT E%CAVATION W!.!P 50lA
FOUNDATION COND.lAAi'L 25 TONS
STAGE 2 QUANTITIES
c�nss n coucRErE
BARREL fJ 1.1926 CY/FT 5L5 CY
WINGS. ETC. 7.7 CY
SILLS 21 CY
TOTAL 61.4 CT
REINFORCING STEEL
BARREL G SILLS IOA56 LBS.
YIINGS,ETL. 322 LBS.
TOTAL IO.7i8 L85.
NLVERT EXCA4ATION WMP Sll1A
FOUNDATION COND.IAAT'L q� TONS
' LAYERS OF 30 LB.
t00FING FELT TO
'REVENT BONDING ITYP.)
D01'IELS
EA. END)
OOWE�S
� °6 �OWEL ITYP.) AT
A IdA%. SPdCING OF 9'-0"
2 LAYERS OF 30 LB.
ROOFING FELi TO
� PREVENT BONO ITYP.)
SECTION THROUGH SILL
! DOIYELS ldAY BE PUSHED INTO GREEN CONCRETE
AFTER SLAB HAS BEEN FLOAT FINISHED
DaIE �
CULVERT SILL DETAILS
�
—�,
\.'
�NATIVE l.IAiERIAL IN
HICH FL01'1 SILL
0 LOYIIFLOWQSIRLAL IN
L-
�
LOW FLOYI
CHANNEL
^J
CULVERT
a a
Oj ' '
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L-
BAFFLES
13 LOCATIONS)
ITYPJ
PLAN OF FLOOR SILL LAYOUT
LOW FLOY/ SILLS DENOTED BY CROSSHATCHED AREA.
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EA. EN011
PROJECT NO 17BP.14.R,90
- � GRAHAM
� COUNTY
�---_ S7aTION: 12+66.58 -L-
�ESIGN ENGGIEER OF FECOFO:
DAiE:
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Transporlatlon 8 Infrasimcture
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Cary, KC 2]513 - 919.6I9.0035
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DEPARTMENT OF TRANSPORTATION
PlLE1Pi
SINGLE 12FT. X 4FT.
CONCRETE BOX CULVERT
STAGES 1 & 2
BILL OF MATERIAL
9Yi 011Ft I C-6