OKTIBBEHA COUNTY — A report from Mississippi Engineering Group says the Oktibbeha County Lake Dam has a solid core and mostly in shape, but it still needs some repairs.
Due to heavy rains, the possibility of a breaching dam in early 2020 forced several citizens to evacuate their residences, but the lake has had issues for several decades, Oktibbeha County board of supervisors board attorney Rob Roberson told The Dispatch. That launched a now two-years-long debate over how to correct the issues, including a proposal from engineer Clyde Pritchard to spend $8 million replacing the structure.
To determine the status of the dam, the board contracted with Flowood-based Pickering Engineering Firm, a business included in larger engineering company Mississippi Engineering Group, in July to conduct a study, which was presented at Tuesday’s board meeting.
Subcontracting with Starkville-based Burns Cooley Dennis Inc., Mississippi Engineering conducted a geotechnical analysis to ensure the dam was up to the Mississippi Department of Environmental Quality standards, a hydraulic analysis to see the probable maximum flood and a dam inundation analysis, which estimates the dam breach parameters.
MEG engineer Bill McDonald said while there are a few places throughout the dam’s core that may be “soft,” the geotech analysis, which evaluates the instability and structure of the embankment, found that the dam is overall safe and would not lead to failure.
“For the most part, the embankment soils were stiff, strong, the kinds of soil you want to effectively form an impermeable barrier, but there are some soft, moist spots,” McDonald said.
While the dam is not close to breaching, the report proved the dam is not up to MDEQ standards, such as having continuous mudslides and the risers, pipes used to set the primary water elevation, not being up to par. MDEQ Chief of Dam Safety Division William McKercher, who attended Tuesday’s meeting, said another issue that needs to be addressed is a log that has wedged itself between the low level outlet pipe, keeping the flow of water from draining all of the way down, which in turn, is why water levels of the lake become so high after heavy rainfall.
While the overall study has been completed, McDonald said he cannot yet give the board a cost estimate because his company is waiting on the final report, and the design work for the dam project would essentially outline how much it would cost.
“We have performed all of the analyses, and now we’re putting that report together, and we are putting that report together by the end of the month,” McDonald said. “Our suggestion (for the board) is that we review that report with MDEQ to make sure that it has satisfied their requirements and their parameters for the things that need to be evaluated, and in concurrent with that, we suggest we review it (with the board).”
Roberson said if he were to guess a price, he could see the repairs estimating around $2 million to $4 million.
District 3 Supervisor Marvell Howard represents the area around the lake and said he is probably the closest resident to the bottom of the dam. While the analysis showed the dam, for the most part, has a strong core, it is still considered high-hazard because two bores were said to be soft, potentially putting residents at risk.
“I understand that 90-percent of that core is in good shape, but there’s that little bit of a percentage that is questionable,” Howard said.
After the county receives the final report, the next step it must take is create a design plan for repairs of the dam. McDonald said MEG does not typically design high-hazard dams, but it has the capability and availability to do so. The county must soon vote on if it will continue to contract with MEG to develop the design or find another company who has dealt with several high-hazard dams in the past.
“We would say, ‘OK, based on this, this is what it would take to design this,’” McDonald said. “This is what it would take for the schedule and the scope of the design and budget for doing that. We would present that to you in February as the immediate next step to keep that project moving.”
While MDEQ does not dictate how the lake must be designed, McKercher said the state must approve the design plan for it to be implemented. Because Mississippi Engineering conducted the analysis, he said it might be easier for the county to contract with the company again because Mississippi Engineering will be familiar with all of the study’s findings.
“In evaluating who is going to be doing the design work, there is certainly some concern,” McKercher said. “… if you look at having a different firm come, they would be able to take those models, and they would be able to use that work, but at the same time, if they’re putting their professional engineering stamp on it, and they’re saying the design is by their specifications, they’re going to want to go through and double check to make sure it matches.”
McKercher said he wanted the initial design plans completed by Feb. 28, but he said he will push that deadline to a later date. Roberson said he would like to begin design work soon to avoid pushback from potential rain.
“When we get into that wet season, we’re not going to be able to go forward with that,” Roberson said.
County court judge qualifying begins
Oktibbeha County will officially have a county court come November.
Due to Oktibbeha County having more than 50,000 people according to the 2020 census, the county is required to establish a county court. After Mississippi Gov. Tate Reeves issued a proclamation Tuesday morning giving consent for a county court, the board of supervisors approved the creation of the court on Tuesday.
Attorneys wanting to run for county court judge have until Feb. 1 to qualify for the position through the Mississippi Secretary of State Office website or at the Oktibbeha County Courthouse.
The general election will be Nov. 8.