NCDOT is upgrading the U.S. 401 intersection in Raleigh to ease traffic congestion. The $45.3 million project includes a continuous flow intersection and reducing left turn conflicts, benefiting the 73,000 daily motorists. Construction challenges include subsurface rock removal and bridge extensions. Completion is expected by 2027.
NCDOT photo
Work included 54-in. diameter drilled shafts; columns were formed and poured; existing caps were extended and poured; and crews were pouring the bridge deck extensions as of early April.
In an effort to ease congestion and improve traffic, construction crews in Wake County, N.C., are upgrading the intersection of U.S. 401 at Ligon Mill Road and Mitchell Mill Road in Raleigh. Work on the $45.3 million project began in 2023.
"When we add the continuous flow intersection, it will reduce traffic delays," said Kim Deaner, North Carolina Department of Transportation (NCDOT) communication officer. "We will be able to move large volumes of traffic through the intersection faster and more safely."
Improvements at the intersection of U.S. 401 and Perry Creek Road also are being made. The section of U.S. 401 in this area sees an average of 56,000 vehicles daily. Additionally, feeder roads such as Perry Creek Road, Mitchell Mill Road and Ligon Mill Road collectively contribute to an additional 17,000 vehicles on average each day.
NCDOT photo
Traffic is heavy during the morning and evening commute. U.S. 401 serves as a main corridor from northern towns and counties, creating heavy traffic volumes during the morning and evening commutes but also throughout the day.
According to David Moore, NCDOT district engineer, keeping the community informed is critical.
"We often get questions about the project due to frustrations related to the construction process. We try to address each question in a way that helps the public understand how the final design will affect and benefit them."
Lane closures have been common, but U.S. 401 hasn't closed for any length of time to cause major delays. Project phasing helps reduce the impacts to the traveling public during commuting times.
Conti Civil LLC of Edison, N.J., serves as contractor on the project, which has its fair share of challenges.
"This area is notorious for a lot of subsurface rock," said Moore. "Crews spend a lot of time removing this rock by blasting and other manual methods in areas where blasting is not able to be done. This has affected grading operations, drainage work and noise wall installations."
Workers are focused on completing Phase I, which involves building and connecting the newly realigned Ligon Mill Road to U.S. 401 just north of its original location. The widening of the bridges over the Neuse River also is under construction.
"The existing bridge structures are being widened to provide additional 12-foot lanes and 10-foot multi-use walkways," said Moore. "This had to begin in the river by constructing causeways that would provide a dry area to begin the substructure work.
Work included 54-in.-diameter drilled shafts; columns were formed and poured; existing caps were extended and poured; and crews were pouring the bridge deck extensions as of early April.
NCDOT photo
Transforming Perry Creek Road at U.S. 401 into a reduced conflict intersection also takes time and patience.
"This intersection will function as a superstreet type design, which reduces the left turn conflicts that are typically encountered at a more traditional intersection," he said. "This design will only allow right turn movements from Perry Creek Road and will allow traffic to free flow on the main U.S. 401 corridor when traffic volumes are lighter but will also be signalized for times when traffic is heavy and is backing up on Perry Creek and at the U-turn locations north and south of the intersection."
Reconfiguring the existing Mitchell Mill Road intersection with U.S. 401 as a continuous-flow intersection will benefit motorists as well.
"This intersection reconfiguration will separate the southbound 401 left turn movements from the through movement prior to the intersection," he said. "This will allow the left turn movement to function concurrently with the free flow of both northbound and southbound 401."
Much of the finished work includes the drainage and wet utilities in preparation for the tie-in of the realigned Ligon Mill Road and widening of northbound and southbound U.S. 401.
NCDOT photo
"Our biggest drainage opportunity for this project was a dual 78-inch pipe operation that began with a directional boring operation under the intersection of U.S. 401 and Ligon Mill Road," said Moore. "The boring was a requirement of the contract to prevent major roadway shutdowns and to reduce impacts on traffic.
"Once the boring operation was completed, the remaining sections of the 78-inch pipes were installed using trenching and shoring operations to excavate for the pipe placement. Once operational, this dual 78-inch system will be used to relocate a stream that eventually feeds into the Neuse River."
The total amount of dirt being moved on the project is approximately 94,000 cu. yds.
Equipment on the job includes Cat 325 and Volvo 245 excavators; a Cat 304 mini-excavator; Cat 950 and John Deere 93 front-end loaders; two John Deere 333 skid steers; and a Link-Belt 238 crane.
Main construction items remaining include the tie-in of the new Ligon Mill Road alignment; completion of the widening on northbound and southbound U.S. 401; completion of the new Mitchell Mill alignment; and completion of noise walls along U.S. 401.
Moore said as each day passes, it's satisfying to witness the changing landscape.
"During the life of any project, there are many questions and complaints about construction and the actual need for improvements," he said. "Once construction is complete, we often hear from some that have complained during the construction phase that they are very happy with the results. The positive follow-up from the public is really appreciated."
All work should be completed by 2027. CEG
Cindy Riley
Birmingham, Ala., native Cindy RIley originally planned on a career in law, but during her sophomore year in college realized journalism was her true calling. A magna cum laude graduate of Samford University, Riley first worked in radio and TV. Named Best News Anchor, Best News Reporter and Best Investigative Reporter by the Associated Press, she interviewed numerous personalities, ranging from Dr. Henry Kissinger and President Bush to Michael Jordan and Captain Kangaroo.
As a print journalist, Riley has covered a variety of topics, including construction, business, health and the arts. In addition to CEG, her work has appeared in special reports for USA Today and the L.A. Times. Other publications have included New South Magazine, Portico, Thicket, Alabama Heritage, B-Metro, Business First and Birmingham Business Journal.
Read more from Cindy Riley here.
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