.jpg)
Moores Creek Dam Issue Found In December
Lexington City Council Feb. 27 voted to move forward with an engineering study at Moores Creek Dam to attempt to determine the cause of the sinkhole that was discovered in December.
“Nobody’s told us, ‘You have to do this’ yet, [but] if we don’t do it soon, I think that will be forthcoming,” City Manager Tom Carroll explained to Council. “I’d rather get in front of it and be proactive, working with our regulators and DCR (Department of Conservation and Recreation), than wait.”
The cost for the study is $170,000, with additional costs being required in the future to take any recommended actions to address the sinkhole.
The city has applied for a grant to cover up to 50 percent of the cost of the study. Patrick Madigan, the city’s director of public works informed Council at that meeting that the application had passed the first two review phases. It had not progressed further in the process as of this past Monday afternoon. In addition to studying the dam and its infrastructure to potentially determine the source of the water that caused the sinkhole, the study will also provide the city with engineering data of the dam and what it’s comprised of at each level, and will also calculate the stability of the dam.
Madigan also noted at the meeting that this is not the first time a sinkhole has occurred at the dam. On July 13, 1977, a 12- to 15-foot wide sunken area, approximately 4-6 inches deep, was discovered after a 10-foot drop in the water level in the reservoir over the weekend of July 8-11. The source of the leak was determined to be in one of the concrete pipes that serves as outflow from the dam, which was repaired. Additional sunken areas were discovered in the same area on Aug. 1 of the same year, with the cause being determined to be another of the pipes leaking.
In an effort to determine if that was the source of the water that caused this sinkhole, the water level of the reservoir was being lowered at a rate of 6 inches per day, but recent rainfall and snow melts have refilled the reservoir at a higher rate than the water was being let out.
“That would be at least another data point,” Madigan said. “Maybe not a smoking gun, or maybe a smoking gun to see if it’s the same problem that happened before.”
Madigan told The News-Gazette in an e-mail on Monday that the water is still being lowered at a rate of 6 inches per day and the reservoir is currently 5 feet below its average level.
David Sigler made the motion to approve spending the funds on the study and the application for the grant. Marylin Alexander seconded the motion, which passed in a 5-0 vote. Chuck Smith was not in attendance at the meeting.
The 4-foot-by-4-foot sinkhole has not grown in size since it was first discovered in December, and the water flowing through it has remained clear. Officials with the city, the Virginia Department of Conservation and Recreation and the Timmons Group – the engineering consultants that are advising the city – do not feel there is any immediate danger of the dam failing.
