Witt explained that if too much concrete was poured and without any joints or cracks, the dam would be under an enormous amount of pressure that could eventually force a complete breakdown.
It may surprise both locals and tourists alike that Ameren Missouri’s Bagnell Dam, at 2,543-feet long, 148-feet tall and constructed with tons of concrete, has its fair share of cracks, large and small.
A popular photo recently shared in the Facebook group, Lake Area Happenings, showed one of these cracks on the outside of the dam walls that concerned some citizens, while others assured the group the crack had been there for decades.
Some of these cracks, which appear to be several feet in length, even have vegetation growing in and around them, but what you can’t see is Ameren’s daily, quarterly and yearly efforts to monitor and inspect these cracks for leakage and movement.
Warren Witt, Director of Hydro Operations at Ameren Missouri, said the electric company would actually be concerned if there were no cracks in the concrete dam. Witt said the dam was designed with specific joints built in, because concrete expands in the summer and shrinks in the winter.
“All concrete dams have cracks,” Witt said. “Earth-bound dams are the ones you have to worry about the cracks, you don’t want any. For concrete, you need them to avoid contraction.”
Witt explained that if too much concrete was poured without any joints or cracks, the dam would be under an enormous amount of pressure that could eventually force a complete breakdown.
By monitoring the cracks with electronic devices and regular Federal Energy Regulation Commission assessments, the engineers at the dam know exactly how much water is leaking and whether or not the crack is growing bigger.
To prevent additional leakage, Witt said, Ameren installs and regularly replaces inner-tube-like water stoppages inside the cracks and joints, which are quite effective at stopping further water flow.
So while Ameren is fully aware of the cracks, you don’t have to worry about the dam collapsing because of them.