Over last weekend, many people availed of the fine spring weather. For those living beside Dublin Bay, the value of the amenity was plain to see. Thousands were out walking the coastline. Many recreational users took to the water; sailing, paddle boarding or kite surfing – some even swam. And yet they had no indication of a pollution incident unfolding in the nearby Liffey estuary.
At 9am on Saturday a large discharge of sewage sludge occurred at Poolbeg outfall due to a tank failure at Irish Water's waste water treatment facility in Ringsend. An aerial photograph taken using a drone, published by The Irish Times on Tuesday, confirmed the discharge was continuing eight hours later.
Irish Water alerted the EPA on Monday, some 48 hours after the incident. In all that time no public alert was issued. It was Tuesday before EPA inspectors were on site, investigating the circumstances and taking water samples. It adds up to a wholly unacceptable response by the utility, which has since apologised. The question has to be asked, however, if the public would have known about the discharge were it not for the actions of an amateur photographer.
In the 1980s when raw sewage flowed out from this same location, it was said it headed straight out to sea on release and posed no health risk, though bathing water samples were show to have high levels of E. coli. The environmental group Coastwatch used a dye study and 5,000 marked sticks to demonstrate sewage could travel to Dollymount beach in 3.5 hours.
The plant has been upgraded since, and Irish Water has consistently underlined the need for it to be upgraded again at a cost of €400 million to cater for a regional population of 1.9 million. In the meantime, excessive levels of nitrogen and phosphorus are still being discharged into an internationally important biosphere on a continual basis. The latest incident underlines the need to speed up works at the plant and for a dependable and prompt public alert system for all major infrastructure operating close to the Dublin Bay.