Description: In an effort to reduce the stormwater runoff and sewage overflow during periods of heavy rain, the Municipal Authority of Westmoreland County embarked on an $8M expansion at the New Stanton Wastewater Facility which included construction of a 4.25 MG precast post-tensioned CSO tank designed and constructed by Dutchland, Inc.

To maximize the space utilization under tight site constraints resulting from high-voltage electrical power lines, the 4.25 MG precast CSO tank is designed in a trapezoidal shape. The footprint of the tank measures 122’ by 192’ by 80’ by 186’ and includes a sloped base slab for drainage and wash down. The most efficient tank design to accommodate the slope was a uniform 2’ thick base slab cast on an angle with wall heights varying from 37’ to 33’. The CSO tank also includes an elevated splitter box that protrudes above the walkways that will split flows into two chambers.

Dutchland manufactured 192 wall panels, 36 walkways, 6 walkway beams, 4 roof panels, 5 columns, and 3 beams for the CSO tank. The on-site construction time for the tank was completed under 12 weeks.