A SINN FEÍN TD said he was informed today by Irish Water that there were “unacceptable levels of manganese” at the Lee Treatment Plant and that this made its way into customers taps.

Irish Water last week released a statement saying it had begun work to clear a build-up of sediment from old cast iron pipes to address water discolouration, but Thomas Gould said he was informed by Irish Water that manganese is the “key concern”.

Gould said he had “no choice but to walk out of today’s meeting” with Irish Water after he was informed of the presence of manganese. 

In a statement to The Journal, Irish Water said it met with Cork-based Oireachtas members today to update them on measures being taken to tackle water discolouration.

Irish Water said that monitoring of the raw water source, and treated water from the Lee Road Water Treatment Plant, indicated “raised levels of manganese” from 27-31 August.

Irish Water added that “in line with standard procedures, it consulted with the HSE and communicated to the EPA”.

Irish Water said the HSE did not recommend any restrictions on the water supply but requested further testing.

“Ongoing monitoring at the water treatment plant since the weekend has shown a downward trend in the levels of manganese,” said the Irish Water spokesperson.

“Sampling is ongoing and we are continuing to share the results and liaise with the HSE.”

‘Naturally occuring’

Manganese is a silver-grey metal that occurs naturally in soil, water and rocks.

It is an important element in our diets and small amounts are necessary for good health.

These small amounts typically come from foods such as nuts, grains and beans.

However, high manganese levels on an ongoing basis in drinking water can be a risk to health and in Ireland, there is a manganese limit of 50 micrograms per litre of water.

Above this level, manganese can affect the colour and taste of water and you should not drink water with manganese levels above 80 micrograms per litre of water on an ongoing basis.

While the regulatory level in Ireland is 50 micrograms per litre, there is currently no scientific evidence suggesting any adverse health effects at levels of up to 80 micrograms per litre.

In a statement today, Sinn Féin TD for Cork North Central Thomas Gould said that for months, constituents have been “faced with dirty brown water coming from their taps”.

He added that he was today briefed that “last week, water with unacceptable levels of manganese left the Lee Treatment Plant and came out to customers taps in Cork city and particularly on the Northside of Cork”.

Irish Water issued a statement last week stating that it had begun a “targeted flushing programme in a number of areas across Cork City in response to increased reports of discoloration”.

It added that this “programme involves isolating and flushing small sections of the water network to clear any build-up of sediment from the old cast iron pipes”.

However, Gould today said that this discolouration “wasn’t just caused by sediment and rust in the pipes”.

Irish Water advised people to not drink discoloured water but Gould said the company “couldn’t even tell me if customers who are blind or vulnerable were notified of this potentially dangerous water coming through their taps”.

Gould also remarked that “no alternative water supply was offered”.

Irish Water advised, in the statement on its website last Friday, that in the event of discolouration, running the tap for up to 20 minutes will usually restore water to a clear colour, at which point it is safe to drink.

Gould called on the HSE and the EPA to “immediately clarify what they knew about the situation last week and what actions they took to protect the ordinary people of Cork”.