20171353 Ver 1_SW Plan_20171023

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S1o►111Wat�1' Highway Stormwater Program
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STORMWATER MANAGEMENT PLAN _.
(Version 2.07; Released October 2016) FOR NCDOT PROJECTS
WBS Element: 17BP.2.R.78 TIP No.: SF-530055 County(ies): Lenoir Page 1 of 1
General Project Information
WBS Element: 17BP.2.R.78 TIP Number: SF-530055 Project Type: Brid e Replacement Date: 7/17/2017
NCDOT Contact: Paul (Andy) Jordan, P.E. Contractor / Designer: Kimley-Horn & Associates
Address: NCDOT Hydraulics Design Unit Address: 421 Fayetteville Street
1020 Birch Ridge Drive Suite 600
Raleigh, NC 27610 Raleigh, NC 27601
Phone: [phone] Phone: [phone]
Email: paiordan(�a ncdot.qov Email: dan.robinson c(il.kimlev-horn.com
CitylTown: Bethel County(ies): Lenoir
River Basin(s): Neuse CAMA County? No
Wetlands within Project Limits? No
Project Description
Pro'ect Len th lin. miles or feet : 082 miles Surroundin Land Use: Rural
Proposed Pro'ect Existing Site
Project Built-Upon Area (ac. 0.3 ac. 0.2 ac.
Typical Cross Section Description: 2@ 11' wide lanes with 4' 6" paved shoulders and 1' 3" metal rails 1@ 25.33' wide bridge
Annual Avg Daily Traffic (vehlhr/day): Desi n/Future: NA Year: 2040 Existin : 1700 v d Year: 2011
General Project Narrative: The bridge replacement on SR 1324 (Kennedy Home Road) conveys Whitelace Creek from West to East and ultimately drains into the Neuse River. The existing bridge ,
(Description of Minimization of Water overall length (OAL) = 31' and width 25.33' will be replaced with a bridge having an OAL = 50' and width = 33'. The new bridge is wider than the existing bridge to provide the
Quality Impacts) required shoulders and lane width necessary for roadway and drainage. The roadway is being widened to provide the 11' travel lanes for safe travel and to accomodate a bike
route. The proposed bridge and roadway improvements minimized the existing overtopping condition and will now convey the 100 yr storm event through the provided bridge
opening.
An existing ditch was filled by the widened typical section from station 13+80 to approximately 14+50 Lt. The existing roadway is normal crown and drains to the existing ditch,
however the proposed design is superelevated away from the ditch and the existing ground adjacent to the new fill slope drains away from the roadway into the farm field. This
proposed condition eliminates the need for replacing the ditch. No new roadside ditches were introduced as part of this project.
Runoff from the bridge is captured on the low side of the bridge in shoulder berm gutter and traffic bearing 2GI's on the north eastern quadrant of the road. The 15" pipe system
is designed to outfall into an existing roadside ditch (with rip rap outlet protection) outside of buffer zones 1 and 2. The existing vegetated ditch will treat the minimal increase in
impervious area from the bridge widening.
Whitelace Creek is a NON-FEMA stream that is shown on Flood Insura�ce Rate Map (FIRM) panel 372035S400J, dated April 16, 2013. The Whitelace Creek area is located
within the Neuse River Special Flood Hazard Area outer floodplain fringe and the existing bridge 55 is not included in the effective Neuse River HEC-RAS model. A hydraulic
analysis on Whitelace Creek was performed to assess the potential flood level increases associated with this project. Based on this analysis, the proposed bridge replacement
project was not shown to cause an increase in the design year or base flood year levels along the study reach of Whitelace Creek.
Waterbody Information
Surface Water Body (1): Whitelace Creek NCDWR Stream Index No.: 27-76
NCDWR Surface Water Classification for Water Body Primary Classification: Class C
Supplemental Classification: Nutrient Sensitive Waters (NSW)
Other Stream Classification:
Impairments: None
Aquatic T&E Species? No Comments:
NRTR Stream ID: Buffer Rules in Effect: Neuse
Project Includes Bridge Spanning Water Body? Yes Deck Drains Discharge Over Buffer? No Dissipator Pads Provided in Buffer? No
Deck Drains Discharge Over Water Body? No (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)