How this precaster in the South stepped up to help rebuild vital infrastructure and restore communities after the natural disaster
When Hurricane Helene tore through eastern Tennessee in September 2024, it didn’t just damage roads. It severed lifelines. Route 321 near Butler, Tenn., suffered a massive washout that cut off residents from schools, hospitals and jobs. The Tennessee Department of Transportation needed a solution that was both immediate and permanent.
The answer came in the form of 408 feet of custom-engineered reinforced concrete pipe, designed to withstand 47 feet of fill depth. And Permatile Concrete Products had less than 90 days to make it happen.
Racing Against Community Need
“Highway 321 runs between Tennessee and North Carolina. It was impassable due to flooding and caused major detours between Boone, N.C., and areas of Tennessee,” Hank Rainero, vice president of sales at Permatile, said. “Having reliable transportation corridors is one of the basic necessities for people to conduct their lives. Therefore, time was of the essence to help these communities get back as quickly as possible.”
The project’s scale was staggering: a double run of 120-inch-diameter, specially designed reinforced concrete pipe, each section weighing approximately 26,000 pounds. At 10 feet in diameter, these weren’t standard highway culverts. These custom-engineered structures were designed to withstand burial depths well beyond typical specifications.
“The original corrugated culvert was totally washed out,” John Rainero, vice president of engineering and construction, said. “The Tennessee Department of Transportation and the contractor determined replacement with concrete pipe would be the best material to provide a resilient, sustainable and permanent solution.”
With the pipe designed to sit under 47 feet of cover, the immense structural loads would be far beyond any standard highway specification. The vertical pressure alone would create enormous demands before accounting for traffic loads from a state highway.
Engineering Under Pressure
Each pipe section required special design shop drawings stamped by Permatile’s in-house professional engineers. The company’s design incorporated the necessary reinforcement and wall thickness, along with proper bedding instructions for contractors to achieve the required performance. The solution used a multi-pronged approach that combined internal and external joint systems to ensure the 408-foot run would remain resilient against future soil shifts or extreme weather events.
But engineering the pipe was only half the battle. The hurricane had affected Permatile’s entire workforce and region.
“This hurricane event in some way or another impacted all of Permatile’s employees and everyone else in our region,” Hank said. “Whether it was washed out roads, fallen trees, loss of power, damage or loss of residences, or obviously in the worst scenario, the loss of life.”
Despite these challenges, the team mobilized quickly.
“We were a little bit lucky that our immediate area didn’t sustain much damage,” John said. “Northeast of us and southeast of us, there was a lot of devastation 15 miles as the crow flies. Butler is in an area between the two where there was a whole lot of damage.”