20180871 Ver 1_SMP_20180622

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Sti)1't73tiVrd1PF Highway Stormwater Program
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STORMWATER MANAGEMENT PLAN �'-�---•
(Version 2.08; Released April 2018) FOR NCDOT PROJECTS
WBS Element: 17BP.14.R.122 TIP No.: B870137 County�ies): Transylvania Page 1 of 3
General Project Information
WBS Element: 17BP.14.R.122 TIP Number: 6870137 Project T pe: Brid e Replacement Date: 5/18/2018
NCDOT Contact: Rand Hene ar, PE Contractor I Desi ner: Ra'ender Gaddam, PE, CFM
Address: 1020 Birch Ridge Rd. Address: 1520 South Blvd, Suite 200
Raleigh, NC 27610 Charlotte, NC 28203
Phone: [phone] Phone:[phone]
Email: rhene ar ncdot. ov Email: ra'ender. addam rsandh.com
Cit ITown: Brevard Count ies : Trans Ivania
River Basin s: French Broad CAMA Count ? No
Wetlands within Project Limits? No
Pro'ect Description
Pro'ect Len th lin. miles or feet : 470 ft. Surroundin Land Use: Steep Hills, Residential, and Woods
Proposed Pro'ect Existin Site
Pro'ect Built-Upon Area ac. 0.2 ac. 0.2 ac.
Typical Cross Section Description: Two 10 ft. lanes with a 6 ft. grassed shoulder with guardrail, and two 10 ft. lanes with a 3 Two 9.0 ft. lanes on the approach with a 3 ft grassed shoulder, and two 9 ft. lanes with
ft. grassed shoulder without guardrail. a 1 ft. shoulder on the bridge.
Annual Avg Daily Traffic (veh/hr/day): Desi n/Future: 560 Year: 2025 Existin : 280 Year: 2011
General Project Narrative: This is a bridge replacement project on East Fork Rd. over Bradley Creek. The existing bridge is 1 span @ 20' -8" timber floor on timber joist. The proposed stucture is a 22' 1"
(Description of Minimization of Water X 6' 6" Aluminum Box Culver, buried 1 foot. No deck drains are necessary. The improvements include roadway grading, widening, shoulder widening, roadway drainage and
Quality Impacts) excavation.
Waterbody Information
Surface Water Body (1): Bradley Creek NCDWR Stream Index No.: 6-6-5
NCDWR Surface Water Classification for Water Body Primary Classification: Class C
Supplemental Classification: Trout Waters (Tr) (HQW)
Other Stream Classification: None
Impairments: None
Aquatic T&E Species? Comments:
NRTR Stream ID: Buffer Rules in Effect: N/A
Project Includes Bridge Spanning Water Body? No Deck Drains Discharge Over Buffer? N/A Dissipator Pads Provided in Buffer? N/A
Deck Drains Discharge Over Water Body? N/A (If yes, provide justification in the General Project Narrative) (If yes, describe in the General Project Narrative; if no, justify in the
(If yes, provide justifcation in the General Project Narrative) General Project Narrative)

1[s�;k Y�r'7W Nor[h Carolina Department of Transportation �`
5l (}Yt t 14 Vi1?PC
� , Highway Stormwater Program ��'�
STORMWATER MANAGEMENT PLAN �`~-
(Version 2.08; Released April 2018) FOR NCDOT PROJECTS
WBS Element: 17BP.14.R.1 TIP No.: B870137 County�ies): Transylvania Page 2 of 3
Swales
Station & Coordinates Surface Base Front Back Dreinage Recommended Actual Longitudinal Rock BMP
Sheet (Road and Non Road Water Width Slope Slope Area Treatm't Length Length Slope Q2 V2 Q10 V10 Checks Associated w/
No. Pro'ects Bod ft H:1 H:1 ac ft ft % cfs f s cfs f s Used Buffer Rules?
� L 11+00 RT (1)Bradley 0.0 4:1 2:1 0.28 28 235 0.70°/ 0.9 1.0 1.2 1.1 No No
L 13+35 RT Creek
Additional Comments

I li�ll"�v�1�' North Carolina Department of Transportation �
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,� , Highway Stormwater Program ,��
STORMWATER MANAGEMENT PLAN �"f=�''
(Version 2.08; Released April 2018) FOR NCDOT PROJECTS
WBS Element: 176P.14.R.122 TIP No.: B870137 County(ies): Transylvania Page 3 of 3
Bridge to Culvert Avoidance and Minimization
Proposed Structure Summary
Sheet No. & Station Sheet No.: 4 Station: -L- 13+14 Number of Barrels: 1
Drainage Area (ac or sq mi : 1.62 Sq. Miles Barrel Width/Diameter ft): 22'-1"
Surface Water Body: 1 Bradle Creek Barrel Hei ht ft : 6'-6"
Culvert T e: Aluminum Box Culvert w/ Headwalls Culvert Len th ft 54'
Avoidance and Minimization Efforts: The culvert is to be buried 1' and will have sills and baffles which will help it imitate the existing stream.
(Bridge to Culvert)
Stream Slope Fish andlor Aquatic Life Passage
Existing Average Stream Slope (%): 1.20 % Existing Low Flow Channel Dimensions Trapeziodal, with a channel bottom 8' to 9'
Proposed Culvert Slope (°/a): 1.20 % in the Stream: wide. Side slopes vary, but are typically around
Culvert Burial 2:1 on both sides. Normal water depth
Proposed Culvert Burial Depth (ft): �� estimated to be 3" to 4".
Existing Streambed Material: Coarse Sand, Small Pebbles and Rocks Proposed Low Flow Dimensions Same as existing, though the 8' width is held
Through the Culvert: throughout
Proposed Sills/Baffles: Yes, the slope here warrants sills and baffles
Existing Low Flow Velocities in the 1.60 ft/s
Stream (fUs):
ropose ow ow e oci ies roug
the Culvert (ffJs): 1.66 ft/s
Alternating Low Flow Sills/Baffles: No, the channel is straight through this section
of stream
Culvert/Stream Alignment
Stream Patterns Upstream and Downstream of There are bends in the stream both upstream and downstream.
the Culvert that Could Affect Fish Passage and
Bank Stability:
Bed Forms Impacted by Culvert (riffles, pools, None
glides, etc.):
Low Flow Floodplain Bench Required? Yes The proposed culvert is wider than the stream, so a bench is required
(provide justification)
Bends at Inlet/Outlet? Yes The stream has bends in the project vicinity but the culvert is skewed to align as best as possible
(describe culvert alignment with stream)
Stream Realignment Necessary? (provide No
justification)
Bank Stabilization: Class "I" Rip Rap on banks
Outlet Velocities
Natural Stream Channel 2-yr Velocity (ft/s): 5 Natural Stream Channel 10-yr Velocity (ft/s): 5.4
Proposed Culvert 2-yr Outlet Velocity (ft/s): 5.1 Proposed Culvert 10-yr Outlet Velocity (ft/s): 6.4
Roadway Geometric Considerations
Evaluate/Describe Roadway Geometric Constraints:
No significant geometric constraints