By Brad Johnson
Register-Herald Reporter
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Improvements and repairs planned at Bluestone Dam over the next 10 years will make the structure safer, but new operating procedures could lead to increased flooding in some areas downstream from the dam, officials said Thursday at a public meeting in Hinton.
“We’ve received the funding we’ve needed to do the upgrades and repairs to the project thus far, and we don’t see any reason why we won’t continue to see that funding stream,” Col. Robert Peterson, commander of the U.S. Army Corps of Engineers’ Huntington District, said.
“We were lucky to report that we did not have areas of concern because of last week’s weather event,” Peterson said in reference to the flooding that took place in Raleigh County and other areas over the weekend. “Our economists have estimated that this structure prevented $32 million in damages” between March 5 and March 15, he said.
Peterson said the dam, finished in 1949, needs upgrades to handle the type of “maximum flood” that the federal government has been focused on since 2005’s Hurricane Katrina.
Currently, there is a 4.7 percent chance that the dam could experience excess water elevations — 1,494.9 feet above sea level and higher — that could threaten the structure’s stability, Peterson said.
By next year, following the current phase of improvements, that probability will hopefully be down to 1.7 percent, as the excess elevation would have to be at least 1,514.4 feet.
“We’re going to buy down the risk by raising the maximum flood control by 20 feet by installing 50 more anchors at the base of the structure,” Peterson said.
The colonel said the risk probability will hopefully be brought down to 0.02 or 0.01 percent around 2020, following all the planned improvements.
The highest “pool of record” — the highest water elevation ever recorded at the dam — was 1,506 feet during the 1960 flood. By next year, the dam should be able to safely handle a repeat of that elevation, he said.
Peterson pointed out that the dam’s operations have been modified because of water elevation concerns. In a serious weather event, if the water behind the dam is rising, “we’ll be discharging as much as we can as fast as we can” in outflow downstream, he said.
“We will not destroy the integrity of this dam if at all possible, so we are going to outflow, and it could cause impacts... it could cause flooding downstream,” Peterson said. “But the feeling is, we’re not going to cause catastrophic failure of that dam.”
He said a water control gauge about 200 meters upstream of the Route 20 bridge records what the outflow and elevation of water is downstream from the dam. When the gauge reaches 10.7 feet, that is considered the “impact stage” of outflow, and dam officials don’t want to release more water than that.
“We just can’t hold more than we safely think we can,” Peterson said.
In January the gauge reached 10.6 feet; this past weekend, the gauge topped at about 10.2 feet, Peterson said.
“If you were impacted by those events, that’s nothing that is probably going to go away,” he said. “You probably need to take the necessary steps to ensure that your property isn’t affected.”
During a question and answer session, Gary Wheeler, a former Summers County sheriff, told Peterson that he owns a building which flooded this year for the first time since he bought in more than 15 years ago.
“It filled up with 32 inches of muddy water and filth,” he said. “Now I basically have a piece of property that’s not useable. So we’re just going to have to get used to living with this?”
“I’m afraid so,” Peterson said. “What you’ve seen in January and this past week can continue to be expected with the normal operations of the dam. And it’s really up to those county flood control managers to ensure that people don’t build structures within those flood areas.”
For more information, contact the Huntington District public affairs office at 304-399-5353.
— E-mail: bjohnson@register-herald.com
