Mistake

R-2615, US 421/US 321 Improvements
Watauga County
Project Overview
The proposed improvements involve widening two-lane US 421/US 321 in Vi1as, an unincorporated
community west of Boone. The roadway generally follows Brushy Fork Creek in a mountain valley. Its
elevation varies, but it generally ranges from 2,740 to 3,420 feet. Figure 1 illustrates the project location.
Figures 2A-2B, Environmental Features Map, illustrate the project study area.
The widening is anticipated to result in a multi-lane roadway, though typical section(s) to be considered are
under development. The project extends from the US 421/US 321 split to SR 1107 (NC 105 Bypass), a
distance of approximately 3.5 miles. No bridges exist along the project corridor, though two culverts and
several pipe replacements or extensions are anticipated.
The project is state-funded. A combined State Environmental Assessment / Finding of No Significant
Impact will be prepared.
Purpose and Need
The project is needed to address increasing peak hour congestion along the US 421/US 321 corridor.
Commuter traffic into Boone from western Watauga County, Ashe County, and Mountain City, Tennessee
is growing in response to employment growth in Boone. Traffic from US 421 northwest of the project
accounts for approximately two-thirds of the US 421/LJS 321 volume within the project limits.
Traffic counts taken in 2018 indicate the current volume on the roadway ranges from 14,000 AADT to
15,100. By 2045, the project design year, traffic volumes along the project corridor are expected to increase
to between 18,200 to 19,600 AADT. (Figures 3A-3B provide the existing and design year traffic
estimates.) Additional capacity along the corridor is needed to accommodate this increased traffic volume
and achieve a Level of Service (LOS) D or better in the project design year.
Crash data obtained and analyzed for the project provide additional evidence of the congestion currently
experienced along the corridor. Figure 4 illustrates the locations and type of crashes along US 421/US 321
during the five-year analysis period. Rear-end and lane departure crashes are by far the most common crash
types, at 45 percent and 24 percent, respectively. This is indicative of congestion exacerbated by left-
turning vehicles. A summary of the corridor's crash rate compared to the statewide average for similar
roadways is provided in Table 1, below. The crash rate for the corridor is higher than the statewide average
for comparable roadways.
Table 1. Crash Rate
Category
Total
Fatal
Non-Fatal
►n: US 4211US 321 from US 321 to SR 1107 (NC 105 Bypass)
Crashes Crash Rate Statewide Average Crash Critical Crash Rate
Rate
267
98
229.72
0.00
77.94
183.55
1.48
56.35
206.64
4.02
69.37
Note: Compared to Statewide Average Crash Rates for US Routes with 2 lanes (2015 - 2017). The cross section does vary,
but two lanes is the prevailing cross section.
Another desirable outcome of the project is to meet the need for bicycle accommodations along US 421/US
321, as identified in the High County RPO Comprehensive Transportation Plan.

Therefore, the primary purpose of the project is to upgrade the existing roadway with improvements that
will provide additional capacity to alleviate congestion and accommodate growth in traffic along the
corridor.
Natural Environment
Surface Waters
Figures SA-SH provided more detailed information on streams preliminarily identified within the project
area. Approximately 25,6601inear feet of streams have been identified, including 3 named streams and
numerous unnamed tributaries. The named streams are listed in the table below. No streams in the project
area are classified as DWR Trout Streams or Designated Public Mountain Trout Streams. (Please note that
many unnamed tributaries shown on the environmental features map are identified as wetlands, based on
National Wetlands Inventory mapping.)
Table 2.
ct Study Area Streams
Named Streams
George Branch
Brushy Fork
Linville Creek
Stream Index Number
8-15-10-2
8-15-10
8-15-10-1
Water Quality Classification
C
C
C
In addition, at least 28 unnamed tributaries, lephemeral stream to Brushy Fork Creek, and 2 unnamed
tributaries to George Branch occur in the project study area.
Approximately 2 acres of wetlands have been preliminarily identified in the study area. Their locations are
also provided on Figures 2A - 2H.
Protected Species
The table below lists the threatened and endangered species for Watauga County. Preliminary field survey
results indicate that no habitat for the listed species exists within the project study area.
�ble 3. Federal Threatened and Endangered Species (Watauga County), as of June 27, 2018
Common Name Scientific Name Federal Status Record Status
Carolina northern flying Glaucomys sabrinus coloratus Endangered Current
squirrel
Gra bat M otis risescens Endan ered Probabl /potential
Vir inia bi -eared bat Co norhinus townsendii vir inianus Endan ered Current
Rusty-patched bumble bee Bombus affinis Endangered Historic
Spruce-fir moss spider Microhexura montivaga Endangered Current
Road mountain bluet Hedyotis purpurea var. montana Endangered Current
Spreading avens Geum radiatum Endangered Current
Northern long-eared bat Myotis septentrionalis Threatened Current
Blue Ridge goldenrod Solidago spithamaea Threatened Current
Bog Turtle Glyptemys muhlenbergii Threatened (S/A) Current
Heller's blazing star Liatris helleri Threatened Current