A staple of Logan Martin Lake is fishermen casting lines, skiers plying the waters and “grouting.”
Logan Martin Dam is built over karstic bedrock prone to erosion by water over long periods of time. The solution is to drill a series of holes through the dam’s foundation to the limestone and dolomite bedrock, and inject “grout” under pressure – in Logan Martin’s case, a cutting-edge mixture of cement, engineered additives and water. Together, the completed holes create a “curtain” to block seepage and fill voids in the bedrock.
Like skiing and fishing, grouting has been done off and on since the dam was finished in the 1960s, said Richard Mickwee, Dam Safety and Surveillance supervisor for Southern Company Generation Hydro Services.
“In 1991, we started a more intensive remediation program, which is called the Logan Martin Deep Grouting Project,” Mickwee said. “The grouting associated with this work is among the deepest in the world, and dam safety at Logan Martin is being enhanced daily by this effort.”
Grouting at Logan Martin Dam is recognized not only for its achievements in dam safety improvement but also for innovations in grouting that have been developed and tested there, Mickwee said.
The grouting project is overseen by the Federal Energy Regulatory Commission (FERC) and its staff of safety inspectors, as well as by a third-party board of consultants who are recognized experts in grouting, geology and dam safety. This oversight is in addition to that by Southern Company engineers and specialists who monitor the dam daily.
“Once the end of the current project has been reached,” Mickwee said, “Alabama Power has pledged to maintain the on-site infrastructure, equipment and personnel needed to continue the grouting for the foreseeable future. This grouting may be targeted at a specific location needing bolstering or for a new program identified by our rigorous dam safety surveillance and monitoring program.”
Mickwee emphasizes the dam is judged safe by Alabama Power, FERC and third-party dam experts.
“We constantly inspect and monitor the facility to ensure its safety now and for generations to come,” Mickwee said. “Alabama Power is committed to this effort. Nothing is more important than the safety of the public on our lakes and downstream of our dams.”