Problem: The Barkley Dam Power Plant in Grand Rivers, Kentucky, faced a serious issue when groundwater began leaking into the powerhouse tunnel through eight rigid steel conduits. These conduits had been installed by an electrical contractor, but the steel couplings became compromised, allowing water to seep into the conduits and the tunnel. This posed a significant risk to the power plant’s operations, requiring an immediate and effective solution to stop further water intrusion. The conduits in question were extremely narrow, with diameters ranging from only 1 to 2 inches. This small size made accessing and lining the pipes extremely challenging. Additionally, the conduits were located 350 feet from the tunnel entrance, complicating access and debris removal during cleaning.
Solution: To resolve the issue, NuFlow Services utilized NuDrain CIPP technology, which involved lining the conduits to create a watertight barrier. The conduits were first cleaned using high-pressure air abrasive blasting with a silica carbide aggregate. Evacuating the debris posed a challenge due to the 350-foot distance from the tunnel entrance, but a 2-inch suction hose was used to successfully remove the debris. Once the cleaning was complete, eight NuDrain liners were consecutively installed within the leaking conduits. To successfully rehabilitate the pipes, the application and curing pressures exceeded 100 psi, ensuring a durable, watertight seal despite the challenging pipe configuration.
Result: All conduit lines were fully lined, and the tunnel wall was sealed effectively, addressing both the initial groundwater intrusion and the unexpected tunnel wall leak. The electrical contractor was highly satisfied with the innovative and swift solution provided by NuFlow Services. The final inspection by the U.S. Army Corps of Engineers confirmed the repair met all standards, with no wrinkling in the conduit bends and minimal loss of internal diameter, ensuring the cables had sufficient space to pass through. 866-430-2134; www.nuflow.com
