The Kentucky River Lock and Dam No. 9 provides the primary water source for more than 325,000 people. It was a century old. And it was definitely in need of some inspection.
Over a decade ago we performed water supply studies that identified a water deficit in the basin during severe droughts. Recent drought conditions, closure of many of the original navigational locks, and growing stability concerns of the lock and dam structures have prompted several projects on the Kentucky River to address these issues and protect the water supply for the next generation.
The Kentucky River Authority brought us in, and we assessed the structure. We looked at the above-water conditions, conducted dive inspections, and took samples (rock and concrete) from the lock walls, main and auxiliary dams, and other structures.
We evaluated multiple dam raising alternatives and developed concepts for the highest rated options. To narrow those options down, we conducted a flood study of the river and a structural analysis of the lock and dam components.
A new dam, immediately upstream of the existing structure, was constructed. Renovations included scour and slope protections and a conveyance system to transfer water from upper to lower pools in droughts. We used in-the-wet construction to reduce costs, risks, project duration, and environmental impacts. These solutions will protect the water supply of seven nearby communities for 50 years or more.