Restoring a Clarifier Outlet Line Without Excavation
Overview
A major U.S. industrial facility discovered that a clarifier outlet line was both leaking and obstructed. Continued operation created the risk of wastewater escaping into the surrounding soil, but the line ran beneath a concrete clarifier where conventional excavation would have required disruptive and difficult civil work.
Motivo removed the obstruction and rehabilitated the existing pipeline using a cured in place pipe liner, or CIPP. The work was completed in approximately two days for $110,000, with no excavation and no facility downtime.
The Challenge
The clarifier outlet line was an important part of the facility’s wastewater infrastructure. The obstruction restricted flow through the system, while the leaking pipe created the potential for wastewater to discharge into the surrounding ground.
The location made a conventional repair especially difficult. Because the line ran beneath the concrete clarifier, excavating and replacing it would have required extensive work around or beneath the structure. This would have increased the cost and duration of the project while creating additional disruption to wastewater operations.
The facility needed a solution that would remove the obstruction, stop the leakage, and restore dependable flow without disturbing the clarifier above the pipe.
The Solution
Motivo first removed the material obstructing the line so the pipe could be properly evaluated and prepared for rehabilitation. Inspection of the cleaned pipeline confirmed that it could be restored in place rather than excavated and replaced.
Motivo then installed a structural CIPP (Cured-In-Place-Pipe) liner inside the existing pipe. The liner was inserted through the available access, expanded against the interior of the host pipe, and cured to form a new structural pipe within the original line. Because the liner was installed from inside the existing pipeline, the concrete clarifier and surrounding ground remained undisturbed. The completed liner sealed the leaking pipe and restored a clear path for wastewater to move through the outlet line.
The Result
Motivo restored the clarifier outlet line to service in approximately two days. The obstruction was removed, the leaking pipeline was structurally rehabilitated, and the facility regained dependable operation of an important part of its wastewater system.
The project was completed for $110,000 without excavation or facility downtime. By rehabilitating the pipe in place, the facility avoided disruptive civil work beneath the concrete clarifier and the cost and uncertainty associated with excavating around a major structure.
A Practical Alternative to Excavation
Wastewater and drainage lines frequently run beneath tanks, clarifiers, buildings, concrete slabs, roadways, and other structures that make conventional excavation difficult. In these situations, even a relatively small pipeline problem can create major operational and environmental consequences. CIPP allows many gravity pipelines to be rehabilitated from the inside using existing access points. By creating a new structural pipe within the existing line, the process can restore integrity and flow while avoiding excavation, demolition, and lengthy interruptions to facility operations.