High levels of manganese reported in Cork water supplies

Water test results for Cork city show five exceedances of manganese levels recorded over a three-week period in January.

Water was tested in Gardiner’s Hill, Gurranabraher, Dillon’s Cross, Ballintemple, Montenotte, Douglas and Thomas Davis Bridge between January 6-27. The regulatory level of manganese is 50 µg/l, yet five instances above this were discovered, including two which far exceeded double this level.

The highest levels recorded were 124 µg/l at Thomas Davis Bridge on Monday, January, 27 and 121 µg/l at Gurranabraher on Wednesday, January 15.

In both Gardiner’s Hill and Dillon’s Cross on Monday, January 13 the level of manganese was 51 µg/l, while it was 54 µg/l in Gurranabraher on Wednesday, January 8

Exceedances

Previous results show eight exceedances in Gardiner’s Hill, including 186 µg/l at the end of August and 128 µg/l in September. There were eight exceedances at Thomas Davis Bridge, including 166 µg/l in September; 130 µg/lin October, and 121 µg/l in August.

There were three previous exceedances in Gurranabraher, including one of 141µg/l in August, as well as four exceedances in Dillon’s Cross and one in Montenotte.

Sinn Féin TD for Cork North Central, Thomas Gould, said: “In Gurranabraher, there was no test carried out in the entire month of January that showed a safe level of manganese in the water.

“They took a test on the 15th January that was 142% above the Drinking Water Regulations and didn’t take another test in the area for the rest of January.”

He called for a Do Not Consume Notice to be issued if the situation continues, noting that the five most recent exceedances now make 29 tests from the end of August to the end of January supplied by the Lee Treatment Plant that show unsafe levels of manganese.

“The water may be safe leaving the plant but it is not safe by the time it reaches people’s homes and businesses - and that is all that matters”, Mr Gould said.

'Ducking and diving'

He accused Uisce Éireann of “ducking and diving” on the issue.

“I met them on February 14. They told me they would send me the January testing results that evening with locations. Instead, it has taken a month to get this information. They are refusing to face scrutiny at a public meeting of Cork City Council.”

An Uisce Éireann spokesperson told The Echo that they have a dedicated taskforce working on Cork city water and a new manganese removal system was installed at the Lee Road Water Treatment Plant in December.

“Following a notified exceedance of manganese at a customer tap, which is normally isolated to that network, Uisce Éireann commence an investigation and typically undertake reactive flushing works. Manganese is a naturally occurring metal that is found in many soils, lakes and rivers." 

While a small amount of manganese is good for human health, the HSE advise that exposure to high manganese levels on an ongoing basis in drinking water can be a risk to health. All exceedances are notified to the EPA and HSE,” they added.