Flooding from Tropical Storm Helene in 2024 exposed risks of aging dams in Western N.C. and Eastern Tenn. Focus on better forecasting, dam modifications and removals to enhance flood management strategies, as costly dam projects are unlikely. Collaborative efforts needed for flood-resilient communities.
George Budak photo —via Facebook
The flooding caused by Tropical Storm Helene in 2024 underscored the dangers of aging dams and flood-control infrastructure in Western North Carolina and Eastern Tennessee.
The flooding caused by Tropical Storm Helene in 2024 underscored the dangers of aging dams and flood-control infrastructure in western North Carolina and eastern Tennessee.
Leading up to the September 2024 storm, some signs already indicated that something more needed to be done before the next natural disaster strikes, Carolina Public Press (CPP) reported June 2, 2025.
A substantial number of aging dams are in poor condition throughout the state with a risk of failure, posing a significant hazard to property or life if they fail. The cost of repairing them is often prohibitive. Instead, dams no longer serving a purpose remain in place despite disrupting a river's flow, impacting the ecology and posing a public risk as they degrade.
In the hours after Helene's rampage through western North Carolina, Erin McCombs, the southeast conservation director for Washington, D.C.-based American Rivers, found a scarce sliver of cell service near her home in Asheville. Her first instinct was to search online for reports of failed dams.
"A lot of the initial reporting was that many major dams had failed," McCombs told CPP, a nonprofit investigative news service in Raleigh.
However, most of those reports were untrue as North Carolina documented 41 state-regulated dams that failed or had significant damage from Helene.
The powerful storm underscored the weaknesses of aging dams in the state's mountainous region and the need for updated flood management strategies.
While large-scale dam projects are unlikely, experts are focused on better forecasting, targeted dam modifications and, in some cases, dam removals. With climate change driving more extreme flooding, communities at risk will need to rethink how to protect lives and property beyond traditional infrastructure.
Dams in Way of Helene's Wrath
One dam at risk of failure during Helene was the Swannanoa River's Lake Craig Dam, 3.5 mi. east and upstream from downtown Asheville.
Nearly 30 in. of rain fell in portions of the Swannanoa's headwaters, raising its level 6 ft. above its record and overwhelming the river. Rushing through a confined and winding channel, the unprecedented flooding scoured the landscape, uprooted trees, claimed lives and destroyed structures.
Debris hauled by the floodwaters collected against the century-old Lake Craig Dam, which also serves as a bridge. Originally used as an Asheville water source in 1886, the dam was increased in size in the 1920s to form a recreational lake and to generate electricity. The reservoir, however, was drained in 1952, but the dam structure remained in place, with water flowing through open spillways.
According to the Association of State Dam Safety Officials, dam failures often occur when water flows uncontrollably over or around a structure due to inadequate spillway design or debris blockage.
When asked by CPP, a spokesperson for the state's Department of Environmental Quality (NCDEQ) was unable to provide an inspection report for the Lake Craig Dam. During Helene, an earthen embankment on the structure's south side was washed out, taking with it a portion of the bridge.
In the case of Lake Craig Dam, McCombs said that "the river found its way," carving a new path by eroding the riverbank and cutting through the dam and bridge, sweeping debris downstream.
"Rivers need room to move," she said. "When we can remove restrictions, communities are safer."
Among other nearby dams damaged during the storm were the Lake Louise Dam in Weaverville and the Lake Tomahawk dam in Black Mountain. Both were overtopped by water and are considered "intermediate" or "high" hazard class dams.
A high hazard dam is a dam that can cause significant property damage or loss of life if it fails or malfunctions. This does not mean that the dam is at a high risk for failure, although it could be. The designation only means that any failure would be catastrophic, CPP noted.
Harnessing Waterways Helped Modernize South
In the early 20th century, the Southern Appalachians experienced a surge in dam construction, driven by the belief that managing the region's abundant rainfall and flowing streams could fuel economic growth by generating hydroelectric power, managing floods and providing recreation.
Hydroelectric systems were central to the south's modernization, supplementing coal power and enabling urban expansion. The era saw the rise of large-scale water infrastructure projects built by two federal agencies, the U.S. Army Corps of Engineers (USACE) and the Tennessee Valley Authority (TVA). Combined, they constructed dams, reservoirs and canals — all aimed at controlling floods and droughts while powering the textile, tobacco and furniture industries.
But plans to develop a major TVA water control initiative on the French Broad River basin never came to fruition, leaving unanswered the question of how such a system might have fared during Helene.
In 1966, the TVA proposed 14 dams on tributaries of the upper French Broad, 74 mi. of channel improvements and a 1.4-mi.-long of levee along the river in Asheville. The waterway flows through four counties in Western North Carolina from its headwaters in Transylvania County, eventually spilling into the Tennessee River.
In all, the sprawling project would have captured a total of 19,200 acres of water, created 6,700 acres of lake area and 183 mi. of shoreline. Its purpose would not have been to generate power, but rather to promote recreation, attract industry, provide drinking water and control floods.
By the TVA's estimate, the project would have yielded $143 million in benefits with construction costs equal to $96 million at 1966 price levels; in today's dollars, the project's benefits would be worth $1.4 billion and nearly $1 billion in costs.
For perspective Hurricane Helene caused more than $60 billion in damages.
But the project never came to be.
Fierce resistance from a strong coalition of residents allied with the fledgling environmental movement, and aided by the National Environmental Policy Act of 1969, led the utility to abandon the plans in 1972.
However, the 92-year-old TVA is still tasked with providing flood control.
James Everett, senior manager of the agency's River Forecast Center, has spent nearly two decades overseeing the complex web of rivers and dams. When Helene unleashed its fury on the region, he and his team faced one of their greatest tests.
"An event like this one was staggering," Everett said. "The people in these communities, they're our neighbors, friends and relatives."
From their centralized forecast center on the ninth floor of the TVA's headquarters in Knoxville, Tenn., engineers face multiple computer monitors analyzing incoming data from gauges, computer radars and measure river flows, lake levels and forecasts.
Covering the wall facing their workstations is a wall-to-wall digital map displaying data for the entirety of TVA's Tennessee River system that includes 49 dams spanning the 41,000-sq.-mi. watershed that encompasses five states from southwestern Virginia to western Kentucky where the Tennessee River meets the Ohio River.
The system of tributary dams, Everett said, operates like a tree in which its main trunk, the Tennessee River, branches upstream into dozens of watersheds, including the French Broad, as well as hundreds of smaller streams and creeks.
During Helene, TVA engineers conducted real-time simulations to predict runoff and manage water releases, keeping a close watch on the tributary dams taking the brunt of the storm. Among them were Douglas Dam on the French Broad near Dandridge, Tenn., and the Nolichucky Dam due south of Greeneville, Tenn., both of which experienced record floods during Helene.
Douglas Lake did not reach its capacity, but during Helene on the evening of Friday, Sept. 27, 2024, the TVA issued a "condition red" precautionary public warning that the Nolichucky Dam could fail. Flood water spilled over the dam's top and eroded its abutments — the earthen material on the edges of the structure.
The TVA issued the warning out of an abundance of caution given the unprecedented magnitude of the storm and the massive volume of floodwater it unleashed, marking the first time in the agency's history that such a warning was released.
Thankfully, the TVA's flood control system in East Tennessee performed exactly as intended, according to Everett. Without the capacity to capture flood water in Douglas Lake, it is likely many cities and towns would have faced costly flooding.
"Before TVA was here, floods that would have run rampant through communities like Elizabethton, Chattanooga, Knoxville, Lenoir City [in Tennessee and] Florence [and] Muscle Shoals [in Alabama] were buffered against Helene, which is remarkable given the size of the storm," he said.
TVA modeling allowed Everett's team to estimate that flood control efforts prevented roughly $400 million in damage to communities downstream. About 90 percent of those avoided losses were in Knoxville and Chattanooga, two of the region's most flood-prone cities on the Tennessee River.
He said, however, that TVA's damage estimates only account for potential structural loss and do not capture the full scope of a flood's impact, including potential lives lost.
Despite the benefits of the agency's flood control operations, they could not prevent severe flooding in portions of east Tennessee, such as Erwin and western North Carolina where intense rainfall fell beyond the reach of TVA's dam and reservoir system.
Costly Dam Projects May Be Hard Sell in Future
Everett and his TVA team are part of a workforce of 7,500 employees who provide power to 7 million people across seven states and oversee river management infrastructure that generates more than $12 billion in annual revenue on the 652-mi. river system.
However, dams are costly to construct and difficult to maintain. Altering a river's natural flow can have significant environmental consequences. Managing a system as complex as what the TVA oversees is no easy task.
CPP noted that since government agencies now face mounting pressure to downsize operations rather than expand them, it is not likely that western North Carolina will see big — or even small — TVA-style flood-control system anytime soon.
The sprawling TVA system, built during one of the most ambitious dam-building campaigns in United States history, is considered complete. No plans exist to build additional dams on tributaries of the French Broad, Everett said.
Instead, the TVA is doing things within its current mandate, such as refining forecasting tools, improving flood response, stewarding shorelines and promoting stream biodiversity.
Meanwhile, Nicolas Zegre, a forest hydrologist of West Virginia University (WVU), warns that flooding in Southern Appalachia is becoming a growing crisis as climate change increases the frequency of extreme rain events, such as Helene and February 2024's floods in eastern Kentucky.
Catastrophic flooding in southern West Virginia in 2016 was partially mitigated by the USACE's Summersville Dam on the Gauley River, which prevented severe flooding in Charleston, Zegre said.
But the devastation in eastern Kentucky in 2025 and North Carolina in 2024 are a stark picture of the problem that dams alone cannot solve, such as averting flooding and landslides in communities at the headwater level in small coves and along creeks that seldom flow.
Dams, while valuable, Zegre said, are not a silver bullet.
"Dams have a lifespan — maybe 50 years," he said. "They serve a purpose, but they aren't the ultimate solution."
In Appalachia, communities are scattered across remote valleys and steep terrain.
"You can't put a dam in every holler," Zegre said. "When we're talking about protecting people and property, we have to think beyond hardened infrastructure."
There Are Potential Options
One of the watersheds hardest-hit by Helene in the western part of North Carolina was the Swannanoa River in Buncombe County, the scene of widespread devastation.
Efforts to manage floodwaters along the river have been a topic of ongoing discussion over many years, but high costs consistently hinder progress.
The USACE released a report in August 2017 analyzing potential solutions for the flooding problems in the watershed. Known as a Section 205 study, the 1948 Flood Control Act authorizes the agency to study, design and construct small flood control projects in partnership with state and local governments.
The feasibility study made in partnership with the City of Asheville recommended flood risk management alternatives for the Swannanoa River in response to damages from two tropical storm systems in 2004 resulting in $54 million in damages to public facilities.
Among the alternatives studied was a dry dam on the Swannanoa at the campus of Warren Wilson College, 7 mi. east of downtown Asheville. Dry dams are designed to temporarily hold and control floodwaters to reduce downstream flooding.
Various designs were considered and an analysis suggested the dam could significantly reduce the flood risk. But, Michael Davis, a USACE public affairs specialist, told CPP that higher than expected projected costs were beyond the program's funding limits.
Another project considered were improvements to the Lake Craig Dam. The report examined the possibility of upgrading that structure and rehabilitating its spillway to better match the normal flow of the river.
According to the report, USACE engineers said a large storm event would likely cause the structure to breach. The proposed modifications to the dam, though, also exceeded funding limits due to costs associated with the project.
The final recommended plan included a channel modification project in Biltmore Village along the Swannanoa, 2 mi. south of downtown Asheville, Davis said. Once again, due to budgetary challenges and decreased revenue during the COVID-19 pandemic, city officials ended up terminating the effort.
He added that the potential exists for a new feasibility study to address flood risks on the French Broad River. In an email to CPP, Davis explained that for a study to move forward it would require funding from Congress and a non-federal sponsor, such as a state or local government, to share the project's cost.
Removal of One Dam Likely Averted Disaster
Still, some costly flood mitigation projects, including dam removals, are moving forward across the mountain region.
In June 2024, three months before Helene cut its destructive path through the Tarheel State, McCombs of American Rivers and Watauga River Keeper Andy Hill watched as a Caterpillar excavator dug its mechanical thumb into the 100-year-old Shull's Mill Dam near the site of a former lumber town on the Watauga River.
Located 7 mi. from Boone, this marked the beginning of a roughly two-week process to demolish the dam and restore the river's natural flow.
According to Hill, taking out the century-old Shull's Mill Dam was done just in time as it would likely have failed during Helene.
"When a dam is removed, the river can flow naturally, allowing floodwaters to disperse their energy and velocity more gradually," he said. "We're learning from these kinds of devastating hurricanes. There are things we can do to set ourselves up to be more resilient in the future."
The Shull's Mill Dam project was part of an expansive effort to remove obsolete and aging dams throughout the United States. The old structure was one of roughly 27,000 dams throughout the state — many of which, McCombs said, are no longer serving a useful purpose.
And American Rivers is not acting alone, although it is a leader in the movement to remove dams and hopes to raze 30,000 nationwide by 2050.
The U.S. Infrastructure Investment and Jobs Act of 2021 included $75 million to remove high-hazard dams in which a failure could cause loss of life.
The removal of aging dams is just a singular component of a much larger reckoning for flood-prone communities in southern Appalachia and throughout the nation. Communities also must consider where to rebuild homes and infrastructure, how to best steward streambanks and which policies to select, such as zoning rules and construction standards.
Building more flood-resilient cities and towns, however, requires collaboration between community advocates, federal funding, state agencies and local governments, each with their own incentives, priorities, timelines and constraints.
A significant hurdle to confront future flood waters is finding common ground among them to minimize future costs and to protect lives.
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