Independent Senator Victor Boyhan, has called on Irish Water to confirm if they deliberately released overflow valves at their Ringsend treatment plant last week.

Due to heavy rainfall, an overflow from the Ringsend sewage treatment plant caused a no-swim notice to be put in place across the entire south Dublin coastline.

“Due to adverse weather conditions during a yellow weather warning event, there was a stormwater overflow from Ringsend Wastewater treatment plant,” Irish Water said in a statement.

“The stormwater overflow operated in compliance with regulations and was fully screened and settled.

“Dublin City Council and Dun Laoghaire – Rathdown County Council, in consultation with the Health Service Executive, put bathing prohibition notices in place at a number of beaches,” it said.

Dun Laoghaire-Rathdown County Council said on Sunday, 9 June, water quality tests had come back for Seapoint Beach, Sandycove Beach, the Forty Foot bathing area, Killiney Beach and White Rock Beach and it is now safe to bathe to in the waters.

“Serious questions have to be asked as to the Ringsend Treatment Plants capacity to deal with waste,” said Boyhan.

“And as to why excessive rainwater is entering the system necessitating valves to release contaminated water into the sea and potentially impacting on people’s health and the environment.

“I am calling on Irish Water “to come clean” and explain what actually happened and did they release effluent into the sea because of capacity issues at the plant.”

Senator Boyhan said he was seeking all the facts and assurances that problems at the plant will be addressed and public representatives will be kept informed.

Irish Water said sewage overflows at the Ringsend wastewater treatment plant happen around 15 times a year, “but mostly in winter, outside the bathing season, when the rainfall is heavier.”