As RTÉ News reports, failure of a processing tank at the locally controversial site led to the overflow, which Irish Water confirmed was from an outfall 1km from the plant in the Lower Liffey Estuary in Dublin Bay, around 9am on Saturday (23 February).
Irish Water says the discharge of ‘activated sludge’ — which “does not pose the same risk to public health or the environment as a raw sewage discharge would” — lasted for around 20 minutes.
But drone images captured on Saturday evening showed the persistence and extent of the pollution incident beside the Great South Wall.
The Ringsend wastewater treatment plant is reportedly running at 20% above capacity as it treats two-fifths of all wastewater in Ireland.
As such, its standard discharge “does not comply with the Urban Wastewater Treatment requirements”, according to an Irish Water statement which also confirmed that the EPA conducted an audit of the affected site yesterday (Tuesday 26 February).