20190849 Ver 1_SMP_20190625

t-li9)lwa:ty North Carolina Department of Transportation
`.atUU7'A1XV.W'T Highway Stormwater Program
STORMWATER MANAGEMENT PLAN
(Version 2.07; Released October 2016) FOR NCDOT PROJECTS
WBS Element: 17BP.14.R.179 TIP No.: SF-440247 County(ies): Henderson Page 1 of 2
General Project Information
WBS Element:
17BP.14.R.179 ITIP Number: SF-440247 Project Type: Bridge Replacement Date: 1/24/2018
NCDOT Contact:
Marc Shown, PE
Contractor / Designer:
Richard Bollinger, PE
Address:
1020 Birch Ridge Rd.
Raleigh, NC 27610
Address:
8601 Six Forks Rd. Suite 260
Raleigh, NC 27615
Phone:
[phone]
Phone:
[phone]
Email:
mshownpncdot.gov
Email:
Richard. BolIingerCa)_rsandh.com
City/Town:
N/A
County(ies):
Henderson
River Basin(s):
French Broad
I CAMA County?
No
Wetlands within Project Limits?
No
Project Description
Project Length (lin. miles or feet):
0.105 mi. Surrounding Land Use: lWoods
Proposed Project
Existing Site
Project Built -Upon Area (ac.)
0.3 ac.
0.3 ac.
Typical Cross Section Description:
Two 10' lanes with 3' shoulders (6' with gaurdrail)
Two 10' lanes with 4' to 6' shoulders
Annual Avg Daily Traffic (veh/hr/day):
Design/Future: N/A Year: N/A
I Existing: 120 Year: 2000
General Project Narrative:
(Description of Minimization of Water
Quality Impacts)
This is a bridge replacement project. Existing bridge 247 is 1 @ 18'-6". Proposed culvert 247 is a 20' x 5' 3-Sided Culvert with headwalls. The 3 sided culvert will be set back
from the banks, and will impact the stream much less than a 4 sided culvert. There are no proposed inlets or pipes, and there is only one ditch that will need to be modified due
to the proposed design. This ditch outlets into the stream, but rip rap is to be used on the banks to reduce the velocity and provide improvements from existing conditions.
NCDOT will attempt to avoid and minimize impacts to streams to the greatest extent practicable during project design.
Waterbody Information
Surface Water Body (1): Shoal Creek
NCDWR Stream Index No.:
6-38-23-4
NCDWR Surface Water Classification for Water Body
Primary Classification:
Class C
Supplemental Classification:
None
Other Stream Classification:
None
Impairments:
None
Aquatic T&E Species?
No Comments:
NRTR Stream ID:
N/A (no NRTR for this project)
Buffer Rules in Effect: N/A
Project Includes Bridge Spanning Water Body?
INo
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
General Project Narrative)
(If yes, provide justification in the General Project Narrative)

1 [i11�1'i1i' North Carolina Department of Transportation
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„ Highway Stormwater Program
STORMWATER MANAGEMENT PLAN
(Version 2.07; Released October 2016) FOR NCDOT PROJECTS
WBS Element: 1713P.14.R.1 i TIP No.: SF-440247 County(ies): Henderson Page 2 of 2
Bridge to Culver Avoidance and Minimization
Proposed Structure Summary
Sheet No. & Station ISheet No.:
4 Station:
12+20.50 -L-
Number of Barrels:
1 1
Drainage Area (ac or sq mi):
0.79
Sq. Miles
Barrel Width/Diameter (ft):
20'
Surface Water Body:
(1)Shoal Creek
Barrel Height (ft):
5'
Culver Type:
3-Sided Culvert
Culver Length (ft)
52'
Avoidance and Minimization Efforts:
(Bridge to Culver)
The proposed 3-Sided Culvert will act more as a bridge than a culvert, providing a setback from the stream banks in most spots. This culvert as
been designed a little taller than it generally would have, in order to keep the culvert length shorter. This keeps the inlet and outlet as far away from
the bends in the stream as possible, making a channel relocation unneccesary.
Stream Slope
Fish and/or Aquatic
Life Passage
Existing Average Stream Slope
1 1.25
%
Existing Low Flow Channel Dimensions
in the Stream:
Trapeziodal, with a channel bottom 8' to 10'
wide. Side slopes vary, but are typically around
2:1 on both sides. Normal water depth
estimated to be 8" to 1'.
Proposed Culver Slope
1 1.25
%
Culver Burial
Proposed Culver Burial Depth (ft):
N/A
Existing Streambed Material:
Coarse Sand, Small Pebbles and Rocks
Proposed Low Flow Dimensions
Through the Culver:
Same as existing
Proposed Sills/Baffles:
N/A (no culvert bottom)
Existing ow Flow Velocities in the
Stream (ft/s):
1.20 ft/s
Proposed ow ow velocities I hroUgh
the Culver (ft/s):
1.20 ft/s
Alternating Low Flow Sills/Baffles:
N/A (no culvert bottom)
Culver/Stream Alignment
Stream Patterns Upstream and
Downstream of the Culver that Could
Affect Fish Passage and Bank Stability:
There are bends in the stream both upstream and downstream.
Bed Forms Impacted by Culver (riffles,
pools, glides, etc.):
None
Low Flow Floodplain Bench Required?
(provide justification)
No
Bends at Inlet/Outlet?
describe culvert alignment with stream
Yes
Culvert sized and aligned such that bends at inlet and outlet will be minimized.
Stream Realignment Necessary? (provide
justification)
No
Bank Stabilization:
Class "II" Rip Rap, 30' Upstream and 25' Downstream
Outlet Velocities
Natural Stream Channel 2-yr Velocity (ft/s):
4.4
1 Natural Stream Channel 10-yr Velocity (ft/s):
6
Proposed Culver 2-yr Outlet Velocity (ft/s):
4.4
jProposed Culver 10-yr Outlet Velocity (ft/s):
6.2
Roadway Geometric Considerations
Evaluate/Describe Roadway Geometric Constraints:
Phased construction to be used during bridge removal and culvert installation.