Report: MS Dam Likely to Fail
In Starkville, Mississippi, county officials recently urged residents in the area to evacuate as a precaution for the possible failure of the Oktibbeha County Lake dam.
In mid-January, the dam had experienced extremely high-water levels from heavy rainfall—causing the lake to nearly double in size to about 900 acres of surface area—and after an inspection by the county’s engineer, was reported that the infrastructure could fail at any time.
Built in the 1960s, the Oktibbeha County Lake dam is located in rural northeastern Mississippi, roughly 8 miles northwest of Starkville.
According to reports, an inspection of the structure in 2016 was reportedly rated “fair.” However, a report in February 2019 revealed ongoing seepage problems that the Oktibbeha County Board of Supervisors—the dam’s owner—said it was unable to fix due to financial costs. These issues later grew and were the cause of a landslide, occurring just feet away from the road above.
Oktibbeha County Lake dam failure 'imminent,' evacuations encouraged https://t.co/OcVYagHsx7— Marguritte Tackett (@Marguritte) January 14, 2020
County engineer Clyde Pritchard reported that Oktibbeha County had been seeking money to repair the infrastructure since a 2014 inspection, but the price tag was estimated to cost $8 million.
Following the report and the dam’s most recent inspection, emergency officials urged nearby residents to evacuate the area as a precaution. Should the dam fail, the damage would be enough to close nine highways and impact roughly 130 property addresses (some of which have multiple homes on the property), according to Oktibbeha County Emergency Management Agency Director Kristen Campanella.
The emergency plan also mentioned the evacuation of 108 structures in the event of a breach. As a means to avoid a total catastrophe, Campanella added that a community safe room was set up as relief until a Red Cross shelter could be put together at a local church.
Last week, the Board of Supervisors held an emergency meeting, where a plan was revealed by Pritchard that insisted that the lake needed to be pumped out by the U.S. Army Corps of Engineers in order to prevent a breach. The plan was unanimously approved by the Board, with all supervisors present.
To make matters worse, just hours after the Board’s decision, a new sinkhole was discovered near the dam, measuring four feet wide and three feet deep. Although there was no water discovered in the sinkhole, the following morning Pritchard performed an additional inspection. He found that neither the sinkhole nor the sliding ground on the dam had experienced any changes.
Since the plan’s approval, the Board has contracted with equipment rental agency Herc Rentals after receiving bids from multiple companies.
As reported by The Dispatch, a set of pumps were delivered from Birmingham, Alabama, to the Oktibbeha County Lake dam on Jan. 17, where a portion of County Lake Road between Riviera Road and Walter Bell Road was closed indefinitely during installation that same evening.
During installation, county officials installed three 8-inch pipes and one 10-inch pipe to siphon water off the lake—a procedure that should decrease the amount of time it takes to lower the lake’s overall water levels.
Pritchard estimates that it will take anywhere from 22-24 days to lower the water level of the lake by five feet, assuming that the area doesn't receive any additional rainfall and the USACE pumps are able to maintain draining the lake at 25,000 gallons per minute.
The Emergency Management Agency also intends to place sandbags along County Lake Road to divert for rainwater and stop a mudslide on the levee from progressing. Once enough water has been pumped out of the lake, workers have been instructed to demolish the dam’s riser—a structure that keeps water inside the reservoir.
Oktibbeha Sheriff's Captain Brett Watson reports that already, through just the use of the pipes installed at the levee last week, the water level in the lake has decreased by two feet.