THE ENVIRONMENTAL PROTECTION Agency (EPA) is investigating a fault at the Ringsend wastewater treatment plant that caused sewage to be discharged into the Liffey estuary over the weekend.

Irish Water has said that the failure of a tank led to the incident and that it is also investigating what happened.

The wastewater plant treats approximately 40% of the country’s sewage and Irish Water said today that the fault caused the untreated sludge to be discharged at about 9am on Saturday.

An amateur photographer using a drone spotted the effluent on Saturday evening, bringing the matter to public attention. 

The sewage at Dublin's South Bull Wall. Eoin O' Shaughnessy / dublincityshots Eoin O' Shaughnessy / dublincityshots / dublincityshots

The sewage entered the water at Poolbeg, about 1 km from the wastewater treatment plant. The faulty tank is now being repaired.

“The EPA is investigating this incident and inspectors are carrying out a site inspection to determine the cause of the incident and to monitor the discharge,” the agency said in a statement today.

Our priority is to ensure that Irish Water completes the corrective actions needed to bring the discharge under control and to protect the Lower Liffey Estuary. 

Irish Water said in statement this afternoon that the plant is currently operating above capacity:

In order to treat the increasing volumes of wastewater arriving at the plant to the required standard and capacity, Irish Water is investing over €400 million in the staged upgrading of Ringsend Wastewater Treatment Plant to allow the wastewater of an additional 400,000 population equivalent.

Green Party representatives have been critical of Irish Water’s response and the lack of a public warning about the incident.

“Two days after a major pollution incident, the company seems to have no clear detail on the failure of their plant. That is not acceptable,” councillor Claire Byrne said today. 

Party leader Eamon Ryan TD said that more details need to be released about what happened.

“The unexplained failure led to a massive volume of raw sewage being released into the bay. That bay has been recognised by UNESCO as an internationally important biosphere but we are not providing the protection it deserves. Seeing the lower reaches of the Liffey full of our own excrement is a sickening disgrace,” he said.