20190992 Ver 1_Avoidance and Minimization_20190723

The NCDOT is committed to incorporating all reasonable and practicable design features to avoid and
minimize jurisdictional impacts, and to provide either on -site or compensatory mitigation of all
remaining, unavoidable jurisdictional impacts. Avoidance measures were taken during the planning and
NEPA compliance stages; minimization measures were incorporated as part of the project design.
Avoidance and Minimization
All jurisdictional features were delineated, field verified and surveyed within the right of way for U-2719.
Using these surveyed features, preliminary designs were adjusted to avoid and/or minimize impacts to
jurisdictional areas. NCDOT employs many strategies to avoid and minimize impacts to jurisdictional
areas in all of its designs. Many of these strategies have been incorporated into BMP documents that
have been reviewed and approved by the resource agencies and will be followed throughout
construction. All wetland areas not affected by the project will be protected from unnecessary
encroachment. Individual avoidance and minimization efforts are detailed below for the project. Site
specific measures are detailed by name and impact sheet number for ease in identification in the plan
set.
General Avoidance and Minimization Efforts
• NCDOT will minimize long-term water quality impacts using the most recent Best Management
Practices for Protection of Surface Waters, as identified in the Federal Aid Highway Program
(FHPM) and North Carolina Administrative Code, Chapter 4.
• Sediment and erosion control measures will accommodate a 25- year storm event.
• NCDOT will avoid placing erosion control devices in wetlands.
• Special sediment control fence will be used at wetlands and low areas along the standard silt
fence.
• Guardrail with 2:1 slopes was utilized throughout the project to minimize impacts to streams and
wetlands.
• Riprap will only be placed in the bed of the channels during stabilization of outlet structures as
necessary to prevent further degradation of the stream systems. These locations are illustrated on
the attached plans.
• Dry detention basins have been proposed at specific locations along the project.
• Ditches have been designed to meet grass swale criteria to the maximum extent practical. These
are summarized in the Stormwater Management Plan.
• Ditches and pipes that outlet adjacent to wetlands have been designed to have non -erosive
velocities.
• Provided larger rock (Class I/ Class II) at ditch tie-ins with jurisdictional features to provide
increased stability at locations with greater volumes and high velocities.
• Interchanges were reconfigured to minimize the overall footprint as much as possible and
therefore reduce jurisdictional and right of way impacts.
Avoidance of Jurisdictional Resources
• Impacts have been avoided for SA, SB, SD, SC, SG, SF, SH, SU, SV, SN, SQ, SY, SZ, SAA, SK, SI, SJ, SM,
SAP, SAO, WA, WB, WD, WE, WL, WM, WG, WN, WQ, WS, WT, OWF, OWE
• Impacts to buffers of SAE, SAF, SAG, SAH, SAI, and SAJ are avoided.
• Pond OWC is being impacted by a City of Raleigh project. NCDOT does not anticipate impacts to
OWC due to roadway construction.

Avoidance/Minimization of Impacts to Stormwater Control Measures
Existing Stormwater Control Measures (SCM) were avoided to the extent practical throughout the
project.
New stormwater management controls were added to meet the requirements where existing SCM
were impacted due to construction.
Site Specific Minimization Efforts to Jurisdictional Resources
• At SE, a box was used to dissipate energy flows in the system (Permit Drawing Sheet 11 of 48).
• SO will be daylighted for 8251f with slopes and guardrails used to minimize impacts (Permit
Drawing Sheet 17 of 48).
• The Ligon Street Bridge alignment along with retaining walls, and noise walls have been
incorporated to minimize impacts to the apartment complex adjacent to Ligon Street and stream
SO and SN. (Permit Drawing Sheet 18 of 48).
• 2:1 slopes with barriers will be used to minimize impacts to SC, with outlet protection embedded
to natural stream elevation (Permit Drawing Sheet 21 of 48).
• The interchange was reconfigured north of Wade Avenue to avoid a culvert extension on SC
(House Creek), therefore minimizing the overall footprint and reducing jurisdictional impacts (Plan
Sheet 40).
• Retaining walls have been designed to eliminate permanent impacts for SX (Walnut Creek), as well
as a Class "I" Rip Rap in the stream bed for SAK to minimize stream erosion (Permit Drawing Sheet
11 and 12 of 48).
• Included a retaining wall at the Jones Franklin Road interchange quadrant D to avoid
encroachment on Lake Johnson Park and Walnut Creek and to minimize impacts to WL (Permit
Drawing Sheet 12 of 48).
• Steepened and reinforced 1.5:1 slopes and barriers in the vicinity (Permit Drawing Sheet 14 of 48)
of ST (Simmons Branch) will be used to minimize impacts to:
o Utilities
o Kaplan Park
o ST, WF, and OWC; impacts to SV were eliminated
Avoidance/Minimization of Human Environment Im
• NCDOT chose a best -fit alignment for the widening of 1-440 that avoids encroaching on Kaplan
Park, Method Community Park, the Berry O' Kelly School Historic District, and the historic Oak
Grove Cemetery.
• Five residential relocations were avoided by replacing the Athens Drive bridge at its current
location.
• Melbourne Road:
o Three residential relocations were avoided by replacing the Melbourne Road interchange
at its current location.
o Revised design of the Melbourne Road bridge from three lanes to two lanes at request of
City of Raleigh to be more context -sensitive to the surrounding neighborhood.
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o Included retaining wall along westbound 1-440 and the Melbourne Road off ramp to avoid
impacting several apartment buildings.
• Right of way impacts to Meredith College, University Club, and greenway have been reduced by
revising the design of the Wade Avenue Interchange. On Meredith College's main campus, the
commuter parking lot is avoided and impacts to the athletic field are reduced.
• Included retaining walls to avoid impacting existing noise walls located on cut slopes along
southbound US 1/64 south of Walnut St and along westbound 1-440 between Lake Boone Trail
and Wade Avenue.
• Shifted the Ligon Street alignment to avoid encroachment to historic Oak Grove Cemetery.
• Included retaining walls for the bridge approaches east of 1-440 for the Ligon Street Bridge to
minimize impacts to adjacent NCSU research facility and Method Townes townhome
development.
• Included a retaining wall at Museum Park to minimize encroachment onto this Section 4(f)
resource.
• Extended a wall along Jones Franklin Ramp A to minimize impacts to the Waters Edge Business
Park.
• Boring large culverts/pipes at Jones Franklin and Western Boulevard reduces the need for multiple
traffic shifts and improves safety during construction in lieu of doing construction phase boring.
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