I-Team: N.C. has 5,600 dams. What happens if one bursts?

<b>I-Team:</b> N.C. has 5,600 dams. What happens if one bursts?

I-Team: N.C. has 5,600 dams. What happens if one bursts?

by JEREMY MARKOVICH / NBC Charlotte

WCNC.com

Posted on November 25, 2013 at 7:01 PM

Updated Monday, Nov 25 at 7:21 PM

An NBC Charlotte analysis found that for 2/3 of the state's most potentially dangerous dams, nobody's sure where the water would go.

ROCKINGHAM, N.C. – The first thing you notice are the tree stumps.

Ledbetter Lake was created in 1880, when they dammed up Hitchcock Creek a few miles north of Rockingham. The dam powered the Ledbetter Mill, at the east end of the lake. It once spun yarn. Now it’s been made into condominiums with a view of the water.

Now, that water is nearly gone. Left behind are old tires, mud, and some empty cans of Budweiser that were enjoyed a generation ago. And, there are hundreds of tree stumps, exposed for the first time in years.

Frank Parker wants the water back for his granddaughter. “She hadn’t seen anything but mud,” he says.

Parker, now 63 with an ever-present ballcap and white beard, has lived on Ledbetter Lake his entire life. His roots are so deep that he lives on Frank Parker Road, which was named for his father (“Best man that ever was,” Frank says). In July 2012, somebody noticed water leaking out from a crack in the concrete. By the time state inspectors got there the next day, another leak had popped up.

So they drained the lake.

Parker formed a corporation to buy the dam a few years ago, after the prior owner’s plans for a hydroelectric power station went bust.

Now, he’s trying to get other homeowners to help pitch in to fix the dam. If they don’t, the lake won’t fill back up, and the lakefront property won’t be lakefront anymore. Parker says that’s affecting home values, and sales.

“Until people are assured there’s gonna be water,” he says, “they just ain’t gonna buy.”

Frank Parker can point out the flaws in his dam. From the bank of the stream below it, next to the old mill that’s been converted into condos, you can see a crack in the 133-year-old brick and concrete. He thinks it’ll cost $1.5 million to fix the Ledbetter Dam. 

The dam is important, but the water is what Parker wants back.

“That’s mine and the people’s incentive,” Parker says. “We want our children and grandchildren to enjoy it the way we have.”


 An interactive map of every dam in North Carolina. High hazard dams are shown in red.

Dams Everywhere

The dam at Ledbetter Lake is one of 5,625 state-recognized dams in North Carolina. Some are tall and made from concrete, like the 150 foot Appalachia Lake Dam on the Tennessee border.

Some are small and earthen, like an embankment at the foot of the Ocracoke Island Lighthouse. Some fall under the jurisdiction of federal agencies like the Tennessee Valley Authority, which is responsible for inspecting and maintaining the 450-foot-tall Fontana Dam in western North Carolina, the tallest in the state.

Others are under the watch of the Federal Energy Regulatory Commission, which is responsible for many of Duke Energy’s dams along the Catawba River. But the vast majority, about 88 percent, are regulated and inspected by the state.

More than 1,300 dams, including Ledbetter, are considered to be high hazard dams. High hazard doesn’t mean a dam is in bad shape, rather it means that if the dam were to fail, the rush of water and debris could cause a lot of property damage, the loss of a major road, or, most importantly, lead to death.

An analysis by NBC Charlotte found that two-thirds of all high hazard dams in the state do not have emergency action plans, or EAP’s, which detail what to look for in an emergency, who to contact, and how to operate. They show what areas would be inundated during an emergency, and they’re what county emergency managers would use to develop an evacuation plan. “EAPs are the single most important tool to have when there’s an emergency,” says Steve McEvoy, North Carolina’s state dam engineer.

They’re also, in most cases, not required. The state can force dam owners to submit EAPs when new dams are built, or when old dams are repaired.

Dam inspectors also ask dam owners to voluntarily submit EAPs, and point them to a template they can download from the state website. The Ledbetter Dam didn’t have an EAP, but will be required to have one before the lake can be refilled.

The average North Carolina dam is 50 years old, and a third of the state’s dams are older than that. Many of those dams now need repairs—in the 1960’s, many used corrugated metal piping which has a lifespan of roughly 50 years. McEvoy said it was an inexpensive alternative, often used for spillways that’s now no longer allowed.

The corrugated piping is, in many cases, decaying. And many dams that weren’t considered to be high hazard now are, simply because people are filling up farm fields with houses and now live downstream.

”There’s a lot of dams built before there were a lot of regulatory standards,” says Mark Ogden, a project manager with the Association of State Dam Safety Officials.

“North Carolina is unique because we’ve been growing non-stop for the past 50 years or so,” says Clark Barineau, from the American Society of Civil Engineers. “Some dams that weren’t high hazard now are because of the growth.”

The ASCE, in its most recent Report Card for America’s Infrastructure, gave North Carolina’s dams a D grade. “Infrastructure is always forgotten until it fails,” Barineau says. “Our inability to invest in our dams is really an inability to acknowledge the problem.”

Admittedly, dams do not fail often. The last major failure in North Carolina came in 2003, when an earthen dam near Hope Mills burst after eight inches of rain. Nobody was hurt, but the resulting flooding emptied the lake, displaced 1,600 people, and caused $2.1 million in damage. A $14 million concrete dam built to replace it failed in 2010, just 18 months after it was finished. The town is currently suing the contractors.

More recently, heavy rains in May caused the overtopping of dams controlled by Duke Energy on the Catawba River. The water flooded houses and roads around the river, but the dams themselves did not fail. Duke has filed emergency action plans for its dams. Those plans, as well as most emergency action plans, are not public. The state cites security reasons.

Still, McEvoy and others find the lack of emergency action plans disturbing, especially in a state that has the second-highest number of high hazard dams in the country (only Missouri has more, according to the Army Corps of Engineers).

“Our weakest point,” McEvoy says, “is our lack of emergency action plans for all of our high hazard dams.”


If the Paradise Point Dam were to fail, the homes on the right of the pond would be cut off. (Picture: Bing Maps)

Questions at Paradise Point

Brett Bumeter knows a little something about dam failures. His grandfather built a pond decades ago.

“The first time he built it, he dug it a little too deep,” he says. It was about 40 feet to the bottom. The earthen dam he built quickly became saturated. One day, there was a storm.  “The dam disintegrated,” he says, “and the water rushed down through the woods.”

The second time around, Bumeter’s grandfather made the pond only 20 feet deep, to keep too much water from soaking through the clay.

Now, Bumeter lives below a dam, a half-mile away from his house. He remembers running across the top of a dam in his neighborhood last year. The heavy rains had soaked not only the earthen dam that holds back the pond above his house, but also the road that runs across its top. “Normally blacktop’s hard as a rock,” he said, “but it got so super saturated that it felt like I was running on a sponge.”

Bumeter’s home is in Paradise Point, a lakeside neighborhood south of Belmont. It’s at the end of a cove, built on an old landfill that just out into Lake Wylie. The house itself sits above the spot where the creek meets the lake.

If something happens to the dam, there would be no way to drive out of the neighborhood. “We could hike out,” Bumeter said, “but that’s not going to help you with a car.”

There would be a lot of mud and silt, he thinks. The rush of water would probably cut a chunk out of the embankment behind his shed. It would knock over trees. It might take out a chunk of his yard.

Or it could hit one of the boulders near the creek bed and cut through the neighborhood, on the way to Lake Wylie. He’s not sure. Nobody’s really sure.

The Paradise Point dam is listed as a high hazard dam in a database maintained by the North Carolina Division of Environment and Natural Resources. It has no emergency action plan listed.

It was also given a poor rating by state inspectors in 2012, meaning the owner, whoever that is, needs to address some of the problems. If, eventually, the state can't find the owner, or if the nobody fixes the dam, state regulators would drain the pond. 

Gaston County alone has 126 registered dams. “It does seem like a lot,” says Tommy Almond, Gaston County’s Emergency Management Director.

He knows where every dam is in his county. From a computer terminal at his office, he quickly pulls up a map and data about the dam at Paradise Point.

“There may be 3 or 4 homes that may be impacted,” he says. “The worst case for Paradise Point is that it could take out the road that serves the many homes back in there. It could isolate those homes until DOT gets a temporary bridge built in.”

In his 17 years on the job, Almond has only dealt with one dam failure; in 1997, an embankment at a small private pond near Bessemer City gave way and flooded the woods. If a failure were to happen today, Almond could pull up his map and figure out who might be in the path of the rushing water.

It's an educated guess, he says. “There’s never really been a complete survey done on downstream inundation,” he says. “We don’t have the technology at the local level to do inundation mapping, per se.”

A man who was volunteering his time to make inundation maps has since died, and nobody else has picked up the project since. Of Gaston County's 126 dams, Almond’s office only has three emergency action plans on file. Two come from Duke Energy dams on the Catawba River—the other is for a dam at Poston Park in Lowell. 

Back at Paradise Point, Bumeter isn’t too worried about the dam. So far, the only thing he’s noticed is extra silt running down the creek.

Over time, it’s extended his yard further into the lake. What does worry him is a multitude of storms and soggy years in the future—years that could lead to a soggy roadway and a soggier dam. “I don’t think it would take that much more of an event to do that same thing to that dam again,” he said.


The Ledbetter Dam, as seen from above when the lake was full (Picture: Bing Maps)

The Inspector


Brad Cole doesn’t like snakes. He ran into a cottonmouth earlier in the day, at another dam. Cole likes to get his dam inspections done earlier in the year. When it gets too warm, they come out.

Cole, an engineer in NCDENR’s Fayetteville office, is at Ledbetter on a warm day in mid-May to give the dam its annual inspection. Since the lake behind it is dry, Cole doesn’t think the dam has gotten any worse. 

“I wouldn’t think it would be bursting tomorrow. It showed itself that,” he says. “It’s something that needed to be looked at, and looked into, and once the engineers started doing their analysis, they found bigger problems that what’s on the surface.” 

He climbs up a series of ladders to get a closer look at the top of the dam.

“There in the corner of where you see the spillway wall and the corner of this box structure, where those two meet is where the problem lies,” he says.

Over the next half-hour, Cole and an assistant walk to the other side of the dam, where an earthen embankment usually holds back water from the lake.

He sticks a rod into the ground to check for dampness. Most earthen dams have a little bit of water seeping out of the bottom he says. Many dam owners have a problem keeping four-wheelers off of the top. Those four-wheelers can lead to erosion.

With so many inspections, it can be hard to keep up.

“We have 2,100 sediment inspections, 300 mining inspections and about 300 dam inspections. That’s with a staff of seven,” Cole says about his Fayetteville office, “That is a challenge.”

His office laid off two inspectors earlier this year because less money was coming in from sediment and erosion fees, a direct result of the housing downturn across the country.

Still, Cole and other colleagues across the state manage to inspect every high hazard dam once a year. That goes above and beyond North Carolina law, which requires high hazard dams to be inspected every two years.

“Most dams are not in a state of repair,” Cole says as he walks across the top of the Ledbetter Dam. “Most are in good shape.”

Many of the ones that aren’t, like Ledbetter Dam, are being repaired. Parker says he hopes he’ll be able to raise enough money for the repairs from homeowners who used to be lakeside.

He's also filed an emergency action plan with the state, a requirement before he can start filling the lake up with water. The engineering costs for the EAP were about $20,000, Parker said. If he can line up the rest of the engineering and the contractors, everything could be fixed by next summer.

“If there’s anything positive about this catastrophe, it’s brought people together,” he says. “We know people now that we didn’t know, and I feel that when we do get water, we’re gonna appreciate it more."

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