The upgrade of the Ringsend WwTW, one of the largest in Europe, demonstrates how constrained wastewater assets can be intensified to deliver significant capacity and performance gains under strict TOTEX and land limitations. The facility has been expanded from approximately 1.6M to 2.4M PE within a fixed footprint, while meeting tightened discharge standards for nitrogen, phosphorus, and suspended solids.

Conventional sequencing batch reactors were retrofitted to aerobic granular sludge and hybrid configurations, enabling process intensification and improved treatment performance. The result is an advanced secondary treatment through a suite of double decker SBRs boasting the largest Nereda installation in Europe.

Biosolids treatment at Ringsend has also received substantial investment and innovation which includes thermal hydrolysis treatment, in-series anaerobic digestion, and struvite recovery. This overhaul of the full sludge treatment process ensures all biosolids produced are suitable for reuse in agriculture.

The project demonstrates how integrated process, structural, and hydraulic innovation can unlock latent capacity in existing assets while controlling both CAPEX and OPEX. These principles are directly applicable to the UK water sector, where AMP8 investment pressures demand scalable, low-footprint, and cost-efficient solutions to enhance resilience and accelerate delivery.