Note: May 31 is National Dam Safety Awareness Day, recognized annually by FEMA to spotlight the benefits that dams and their safe operation can provide to communities. Today, we look back (and to the future) on the topic of dam safety in North Carolina with WithersRavenel co-founder and Executive Vice President, Sam Ravenel, PE.
When Sam Ravenel graduated from North Carolina State University with an engineering degree in 1974, working with dams was not on his radar.
Ravenel started working for the state on erosion control out of a regional office in Charlotte, putting his education and interest in stormwater and environmental engineering to work. The state didn’t place much emphasis on dam building or safety at the time.
Then came Feb. 22, 1976. An earthen dam failure on the Buncombe-Haywood county line killed four members of a Newfound community family, carrying one of the bodies three miles. That got the state’s attention.
“The legislature said that we can’t have this,” Ravenel said. “Suddenly there was a lot of emphasis on dam safety, federal funding. We went from no dams to nothing but dams.”
Soon Sam Ravenel had a different role with the state of North Carolina – inspecting dams. While his experience was limited, Ravenel dove headlong into the challenging new job. After a few years and a few hundred dam inspections, he became the state’s Assistant State Dam Safety Engineer in Raleigh.
Improving safety and a serendipitous meeting
When Ravenel went to Raleigh, he was busy with inspections while helping the state write new rules and regulations on dams. The rules have been modified over the years, but a lot of the groundwork Ravenel and his colleagues laid in the 1970s underpins the state’s dam safety framework today.
Ravenel came across some dams in the late 1970s that were in dire shape.
“I remember looking at a dam, walking around it. As you put your foot down, the water was pumping up under your feet.” Ravenel recalled a small hotel directly under the dam, and was grateful that his work with the state was helpful in this instance and others.
“In the early days there were a lot of marginal dams,” he said. “I think we did a lot of good.”
Another memorable moment from working in Raleigh was meeting another young state engineer who was set up just down the hall: Tony Withers.
“We both left the state offices in 1980 for other work, then we came back together in 1983,” Ravenel said. The young company Withers & Ravenel, now WithersRavenel, had dam safety and engineering as part of its foundation.
Costly to repair
A challenge for dam owners through the years has been rehabilitation expenses. Ravenel recalls many instances when a farmer had a dam he considered a resource, only to have someone place a home somewhere beneath it, turning the dam into a liability. Suddenly, a low-hazard dam becomes a high-hazard dam, changing the rules for the farmer. And for a dam that needs fixes, rehabilitation costs can reach hundreds of thousands of dollars.
“It doesn’t do us any good to study dams if we can’t afford to fix them,” he said. “Funding of repairs is the Achilles heel of the (existing) program.”
Today, most dams Ravenel encounters on the job are older dams that happen to be where a new subdivision is being built. Repair costs remain an issue.
“There’s pressure on us to come up with a cost-effective way to repair these dams, so you have a safe dam that protects the homeowners’ association,” he said.
And forget about building dams. Changes in water quality and other rules have made new construction uncommon.
“In the ’70s we were building dams and draining swamps,” Ravenel said. “Today we are draining dams and building swamps.”
Changing technology, dam work today
One of the biggest changes in dam safety from an engineering evaluation standpoint has been in technology, specifically computational power.
Ravenel recalls the 1970s, and walking to the state administration building to run an analysis.
“You’d get your computer cards in, then wait in line for an answer,” he said. If you got one card out of order? Start all over again.
Today, Ravenel enjoys sitting at his desk doing analyses, with an abundance of resources at his fingertips.
“We’ve went from a horse and buggy to jets,” he said.
Having that “jet” power is important today, as Ravenel and other WR engineers work on a current contract for the state evaluating dams on a short timeline. With dam failures in recent years following hurricanes, North Carolina enlisted WithersRavenel and a handful of other firms to quickly evaluate high-hazard dams across the state before hurricane season ramps up.
But even with the increase in technology, there’s still no substitute for experience. That’s one of the many reasons why Ravenel loves working with dam safety: he enjoys the creativity and problem-solving.
“There’s more individuality in the design,” he said. “It’s still the Wild West. We’re always looking for new, innovative ways to skin the cat. I have more fun with dams than anything I do.”
Our services, dam rules
WithersRavenel provides a range of dam design and rehabilitation services as part of our Stormwater Division. Visit the North Carolina Division of Energy, Mineral, and Land Resources’ website for more information on dam safety and regulations in North Carolina.