A day-long sewage leak polluted a Dublin beach by more than 100 times the Blue Flag standard, it has emerged.
Water quality tests revealed the E.coli contamination in Balbriggan was five times the upper limit for safe bathing waters - but 100 times the top marks for cleanliness. Another bacteria of the gut that causes severe gastroenteritis, called enterococci, was 10 times recommended levels.
An investigation is under way into how an alarm failed to warn engineers that human waste was flowing unnoticed into the Irish Sea from an unmanned pumping station for 26 hours.
The Environmental Protection Agency said: “The fact that this occurred at all shows there was a failure in the wastewater treatment plant system.” It is working with Fingal County Council (FCC) to determine the cause of the incident, its impact, and what measures can be taken to stop it happening again.
Council chiefs said the test results indicated significant contamination of the bathing water by faecal material on Tuesday and backed its decision to close the beach to bathers.
“We have continued to sample water quality at the beach and it will remain closed until the samples taken return values that are within the European Bathing Water Quality Mandatory Limits,” it added.
Quality levels at a nearby Blue Flag beach in Skerries - where a second pumping station was also out of action for two hours on Tuesday - are safe, tests showed.
The alarm was raised when a member of the public spotted human waste washed up on the beach at Hampton Cove in Balbriggan on Tuesday afternoon. It later emerged Isaac’s Bower pumping station had stopped working more than a day earlier due to power cuts from bad weather.
Council chiefs admitted it was not possible to accurately measure the exact amount of sewage discharged, but it was believed to be in the region of 3,500 cubic metres of waste.
Lar Spain, a senior engineer with the council, said it was also not yet known why a back-up power supply for the alarm failed. There was no on-site generator. “Unfortunately, with reduced staff numbers we have to rely on instrumentation to warn us when these things happen, and if that instrumental fails it leaves us on the back foot,” he said.
Kevin Tolan, chairman of Balbriggan Chamber of Commerce, warned the same could happen again as the station tries to cope with the town’s population which almost doubled during the building boom.
“Balbriggan is a working fishing port and to have raw sewage flow into the sea for 26 hours in 2012 is totally unacceptable,” he said. “We want to know what emergency reactions plans they had in place to deal with it, why the alarm didn’t go off and what happened to the back-up system.”
Campaigners against a giant sewage plant in the Fingal area also claim the pollution shows engineers and technology cannot stop an environmental disaster.
Brian Hosford, chairman of Reclaim Fingal Alliance, said if a larger plant was built, a bigger catastrophe could happen. “We believe a monster plant will have a detrimental effect on communities, the farming, horticulture and fishing sectors, and destroy an environmentally sensitive coastline, which has several areas of special protection,” he said.
Fingal County Council said larger plants had a significantly higher level of engineering resilience, with on-site power generation and overflow storage capacity.
PA