Lafleche Dam Low Level Outlet Conduit Remediation
The Lafleche Dam in southwestern Saskatchewan was originally constructed in 1958. The dam’s reservoir (Thomson Lake) is used for municipal water supply, irrigation and recreation. The dam offers flood protection, and its low level outlet conduit is needed for reservoir management and riparian flow passage.
In 2018, an inspection of the conduit revealed severe deterioration of the pipe which presented a significant dam safety risk due to internal erosion. KGS Group developed a solution using an array of innovative conduit replacement and rehabilitation methods, including trenchless technologies such as slip-lining, Cured in Place Pipe (CIPP) replacement. The work required excavations and other construction activities at the toe of the in-service dam which necessitated a comprehensive dam safety surveillance program. KGS implemented a state-of-the-art instrumentation plan with telemetry to monitor the performance of the dam during critical high risk construction stages.
The project was completed on schedule and within budget just before winter onset, under a relatively short construction season. The low level outlet was returned to full service in September 2022 following final commissioning of the new slide gate and the cathodic protection system.