The challenge
In a wastewater treatment plant, concrete is not judged on strength alone. The tanks have to stay watertight and withstand permanent contact with sewage, and their tolerances are set not by the contractor but by the equipment that will sit on them — a scraper bridge forgives nothing. The programme was not ours either: we worked as structural subcontractor inside the main contractor’s schedule, with the process and M&E crews waiting on each structure in turn.
Our solution
We organised the structural work by structure rather than by trade, so each tank was handed over complete and released immediately for its equipment. The circular tanks were reinforced and poured in continuous phases, the rectangular walls formed with steel formwork that gives a repeatable finish, and in parallel we built the service buildings, the village pumping stations and the rising mains — so the plant would not sit waiting for the network that feeds it.
