SUNDAY EDITION: Kentucky's push to upgrade dams lacks enforcement plan
State faces challenges as it seeks to ensure dams can handle extreme storms.
Thursday, June 5th 2014, 5:36 pm EDT by
LOUISVILLE, Ky. (WDRB) – Nearly half of the high-hazard dams in the Louisville area inspected within the last year failed to meet requirements for safely storing and passing massive amounts of rainfall, Kentucky Division of Water records show.
Four of the nine dams were out of compliance with rules meant to ensure that the structures can withstand a torrential storm, and regulators have ordered the dams’ owners to make upgrades.
Kentucky’s dam safety branch is increasingly focusing on whether dams can handle extreme -- and possibly unprecedented -- amounts of rainfall. Scarcely mentioned before 2013, “hydraulic capacity” now occupies its own place in inspection reports.
Within the past year, the Division of Water began mandating that inspectors review dams' capacities, said Shane Cook, engineering supervisor of the Division of Water’s dam safety and floodplain compliance section.
In the past, Cook said, determining whether dams were in compliance depended on the individual inspectors and “whether or not they looked at it.”
More dams could be violating the requirements, since most of the region’s 24 high-hazard dams haven’t been inspected since 2012 – including 10 in Jefferson County. Those dams are due for their routine biennial reviews this year.
analysis of inspection records obtained under an open-records request, and interviews with engineers, dam experts and safety advocates, raises questions about how the state is proceeding as it requires dam upgrades:
-There is no enforcement strategy.
Cook said the Division of Water hasn’t decided how long to give owners to bring their dams into compliance “since we just started the program.” As a result, some high-hazard dams that inspectors have flagged as deficient could linger without improvements for years.
-Building a new spillway or making other changes may be cost prohibitive, and the state offers no dedicated funding source.
“There do need to be some conversations – policy conversations – about how these things get paid for in the future,” said Lori Spragens, executive director of the Association of State Dam Safety Officials.
-The current Kentucky standards may change.
Cook said he would like Kentucky to join Ohio and other states that have revised their precipitation thresholds, although such a study hasn’t been budgeted. “I don’t want to make somebody do a $10 million capital construction until I know what the study is – which may be two years from now,” he said.
Asked why the state is requiring dam owners to meet standards that may not last, Cook said: “If I don’t send letters out saying that, I’m just ignoring the issue, and also I’m not giving them the chance to do the planning.”
High-hazard dams aren’t necessarily unsafe, but the classification means property damage and even death are likely if the structures fail.
At least 400 dams failed or almost failed between 1990 and 2010 in the United States, killing 16 people, according to the dam safety association. Two dams failed in Kentucky during that time: A Boone County dam partially collapsed in 1993, stranding residents and damaging roads, and a Martin County coal slurry dam broke in 2000, polluting the Big Sandy and Ohio rivers.
In Iowa, Lake Delhi Dam didn’t meet the state’s capacity requirements when it failed in 2010 during a flood, according to a consultant's report.
Ideally, dams that aren't compliant should be brought up to code “as soon as possible,” said Michael E. Kalinski, a University of Kentucky civil engineering professor.
“It should be a concern because those criteria are in place to protect the public,” Kalinski said. “If we know about it and we don’t do anything about it – that’s kind of a problem.”
The Division of Water has notified owners of four dams – Lake Nevin Dam and the Bullitt County Sportsmen’s Club Dam in Bullitt County; Harmony Lake Dam in Oldham County; and Wallitsch Dam in Spencer County – that they must make upgrades. The state hasn’t taken any enforcement actions.
Inspectors concluded Lake Nevin Dam at Bernheim Arboretum and Research Forest was in good condition during a September 2012 inspection. But the dam’s ability to hold and process 13.5 inches of rain in a six-hour period represents less than half the amount required by state regulations.
Such design concerns only became an issue after several buildings were built downstream, forcing inspectors to give the dam a high-hazard classification. A house and a fire station could be flooded if the dam breaks, according to a state analysis.
Bernheim executive director Mark Wourms said his organization’s research shows the highest rainfall in the area over a six hour period is about 12 inches. But the state requirements are much higher, so officials ordered Bernheim to bring the dam into compliance.
Wourms estimates it could cost as much as several hundred thousand dollars to upgrade the dam.
Bernheim has proposed lowering an area in the northwestern corner of the 32-acre lake to “spread out the overflow” in the event of heavy rains – essentially acting as an emergency spillway. Wourms said negotiations with state officials are ongoing.
“From an organizational perspective, a not-for-profit organization who is here to connect people with nature – that’s a hard thing to kind of have hanging out there,” Wourms said.
In March, the state advised Beam Global that it must improve the Bullitt County Sportsmen’s Club Dam because it can pass roughly 22 inches in a six-hour period, or about six inches less than the county requirement.
A nearby house and first floor of a bourbon warehouse could be inundated if the dam breaches, according to the Division of Water.
A Beam spokeswoman said in a statement that the state's calculations are incorrect and that it is working to resolve the dispute. A state spokeswoman responded by saying:
"The Division of Water is always open to resolving any disagreements regarding inspection reports with dam owners through discussions and re-inspections."
State inspectors noted in inspection reports in 2012 and 2013 that Harmony Lake Dam in Goshen, Ky., failed to meet the state’s standards and ordered it upgraded.
The dam’s capacity is about 25 percent of the county requirement.
The Oldham County Environmental Authority, which owns the dam, has no plans to make any changes, chairman Horace Harrod said in emailed responses to questions. Harrod said his organization disagrees with the state’s classification, which he claims is based on a “faulty” 1985 analysis.
Harrod also said the Division of Water hasn’t responded to his organization's 2011 analysis that purportedly shows no homes are at risk if the dam breaks. A division spokeswoman said a state analysis completed this year shows two houses could be inundated if the dam fails.
Privately-owned Wallitsch Dam can handle eight inches of rain in a six-hour period, or 20 inches below the Spencer County requirement. The state has ordered changes to the dam, even as a spokeswoman acknowledged that a trailer in the potential path of flood waters “may be abandoned and not livable now.”
The dam’s owner did not return a phone call seeking comment.
Kentucky’s regulations for high-hazard dams are based on the maximum “probable” rainfall in a six-hour period. Cook said the state uses calculations based on federal studies done decades ago and are considered “worst-case” scenarios.
“The guidelines that we use are so extreme,” he said. “Have you ever known of it to rain 28 inches in six hours in your lifetime?”
Cook said other states are weighing changes to their regulations based on new studies. The updated research has led to the six-hour rainfall amounts being lowered by as much as nine inches, he said.
State officials say the National Weather Service and National Oceanic and Atmospheric Administration are discussing a nationwide study of maximum rainfall thresholds, and Cook said Kentucky would like to adjust its standards, which would have to then be modified in state regulations.
For now, the Division of Water hasn't set aside money for such a study.
Gordon Garner, the former director of the Metropolitan Sewer District in Louisville, said unpredictable weather ought to be factored into any revisions.
“I would also consider this a potential issue for … Kentucky or any other state to be looking at in the context of climate change and the documentation that’s there,” Garner said. “The standards we used to use for rainfall frequency and duration are obsolete.”
Projections by the U.S. Environmental Protection Agency, for example, suggest heavier downpours are possible in the southeast and Midwest in the coming years as a result of climate change.
Derek Guthrie, executive director of the Kentucky Society of Professional Engineers, said it’s prudent to reconsider data that goes back decades.
He described designing dams, stormwater systems and other facilities based on coping with massive rainfall amounts a “raging debate” among engineers.
“The likelihood of something like that ever occurring is obviously very remote, but when it does it’s very catastrophic,” Guthrie said. “So you’re balancing policy issues with what may be ultimately fiscal realities.”
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