In March 2019, the N.C. Department of Transportation selected a design option called Alternative 7 for intersection improvements to U.S. 401 at Ligon Mill Road and Mitchell Mill Road.
This decision was made based on the analysis of project impacts and comments received from the public, stakeholders and agencies at a Dec. 4, 2018 public meeting, various other meetings, and a public comment period that ended Jan. 5, 2019.
In 2020, additional traffic studies indicated improvements were warranted at the Perry Creek Road intersection to improve traffic flow along the U.S. 401 corridor. NCDOT decided to extend the project limits to include improving the intersection at Perry Creek Road and U.S. 401.
The extended project area does not add additional lanes to U.S. 401. The only construction outside of the existing footprint is the addition of three U-turn sections in the vicinity of Harnett Drive, where the footprint would be widened to create slightly better U-turns. No additional through lanes will be added near Perry Creek Road. Postcards notifying residents within the project study area of the Perry Creek Road addition were distributed Jan. 7, 2022.
Alternative 7 would involve building a "continuous-flow" intersection with Mitchell Mill Road and an "offset tee intersection" with Ligon Mill Road. An offset intersection is two tee intersections with the two streets intersecting with the main road at different points.
Ligon Mill Road would be realigned to cross U.S. 401 approximately 1,500 feet north of the current intersection, offsetting the intersection of Ligon Mill Road with U.S. 401 from the Mitchell Mill Road intersection with U.S. 401. The existing Ligon Mill Road intersection would be removed, but portions of existing Ligon Mill Road would stay in place to provide access to properties on the west side of U.S. 401.
All movements from and to Ligon Mill Road would be accommodated at the new Ligon Mill Road intersection with U.S. 401. The existing Mitchell Mill Road intersection with U.S. 401 would remain in place and would be configured as
a "continuous-flow" intersection
A continuous flow intersection is one at which left turns from the main road cross over the opposing travel lanes ahead of the intersection and travel on a separate roadway to the side street. The left turns can then move at the same time as the through traffic on the main road.
Traffic wishing to turn left from southbound U.S. 401 onto eastbound Mitchell Mill Road will turn left onto a connector road to be built east of U.S. 401. The connector road — which would intersect with U.S. 401 between the Mitchell Mill Road and Ligon Mill Road intersections — would allow left turning traffic from southbound U.S. 401 to turn onto eastbound Mitchell Mill Road at the same time without stopping through traffic on U.S. 401 at the Mitchell Mill Road intersections.
Right turns from westbound Mitchell Mill Road onto northbound U.S. 401 would use the connector road to access northbound U.S. 401.
Left turns from westbound Mitchell Mill Road onto southbound U.S. 401 and right turns from northbound U.S. 401 onto eastbound Mitchell Mill Road would continue to be made at the existing Mitchell Mill Road intersection with U.S. 401.
At Perry Creek Road, the existing intersection will be revised to become a “reduced conflict intersection" with median U-turns. Although the existing traffic patterns will change, drivers will be able to use the road after the improvements are completed.
For traffic turning from U.S. 401 onto Perry Creek Road, drivers will be able to use the existing left turn lanes once these improvements are completed and it will be similar to the existing configuration.
For traffic on Perry Creek Road, the intersections will be reconfigured to only allow right turns onto U.S. 401. For eastbound Perry Creek Road, all drivers will turn right onto southbound U.S. 401. Drivers wishing to continue eastbound on Perry Creek Road or to access northbound U.S. 401 will be required to make a U-turn at a traffic signal that will be installed 1,500-feet south of the U.S. 401 intersection with Perry Creek Road.
For westbound Perry Creek Road, all drivers will turn right onto northbound U.S. 401. Drivers wishing to continue westbound on Perry Creek Road or to access southbound U.S. 401 will be required to make a U-turn at a traffic signal that will be installed 800-feet north of the U.S. 401 intersection with Perry Creek Road.
Additional information on how reduced conflict intersections work can be found here.