Clonakilty Drainage Scheme (Carberry-Muskerry Wastewater Treatment Plant)

Client: EPS Pumping and Treatment Systems
Services: Temporary works design, supply and installation of ground support system

The Carbery/Muskerry Wastewater Treatment Plants DBO (design, build and operate) and O&M (operate and maintain) Contract for €6million is primarily a contract to carry out upgrade works to the existing wastewater treatment plant in Clonakilty, providing a treatment capacity of 20,500PE (population equivalent). It also includes the construction of a storm water retention tank and upgrade works to the existing Pumping Station at Long Quay.

Working for EPS, Trench Control designed and installed an octagonal cofferdam to suit the profile of a very constrained site in order to facilitate the construction of a storm holding tank approximately 24m in diameter. The temporary works included sheet piling and internal bracing for a total excavation depth approaching 4m. The internal bracing worked primarily in hoop compression to eliminate any internal raking or flying shores providing a clear working space for the construction of the tank. Groundwater control was a critical issue at the site because of the permeable gravels prevalent across the site and so installation accuracy of the sheet piles was crucial the success of the project.