Sewage likely to be released into Dublin Bay for some time to come
Analysis: Clonshaugh treatment facility will ease pressure on Ringsend, but more capacity will be needed
Poolbeg Ringsend water treatment facility in February. Photograph: Eoin O’Shaughnessy/Dublin City Shots
It is by far the largest sewage treatment works in the State, catering for 40 per cent of waste water generated in Ireland, yet for many years Irish Water’s treatment plant in Ringsend has been unable to cope with that load.
It means partially treated sewage is frequently discharged into Dublin Bay. There are particular difficulties after periods of high rainfall – which are predicted to become more frequent due to global warming.
Inevitably, the plant does not comply with Environmental Protection Agency (EPA) and EU standards and is increasingly incurring the wrath of the European Commission. This week the EPA, in its latest report on waste-water treatment performance, criticised the pace at which Irish Water is fixing deficiencies in treatment infrastructure as raw sewage continues to be released into the environment at too many locations. The Ringsend facility was very much in its sights.
It opened in 2003 with a capacity to cater for a population of 1.64 million. It now serves an average population of 1.9 million, which can increase up to 2.3 million during busy periods. Waste water released from the overloaded plant into the Lower Liffey Estuary will continue to breach treatment standards until the plant is upgraded to provide additional treatment capacity – and that won’t be all done until 2025 at the earliest.
Construction work began in 2018 to provide additional treatment capacity at Ringsend for an extra 400,000 people. It is due to be completed in 2020. Further work to bring treatment capacity up to a total of 2.4 million people is due to begin in 2021. Irish Water, however, recently revised the expected completion date for this from 2023 to 2025.
Even that capacity may be inadequate, given current loads can peak at 2.3 million, more extreme weather events will test the system, and the Dublin region is set to see the most pronounced population growth in the country – Irish Water says its calculations are based on Dublin’s population increasing by 450,000 to 2.35 million in 2040.
Irish Water has factored in projected population growth and increased commercial activity, which means wastewater generated in the greater Dublin area will increase by more than 50 per cent during the next 30 years. Having adequate treatment capacity is vital to protect public health, safeguard the environment and facilitate social and economic growth in the capital.
The irony, however, is the utility faces major difficulties in getting planning approval for infrastructure projects designed to improve treatment of waste water and enhance bathing waters in rivers and the sea. They inevitably face large numbers of objections, if not legal challenges.
There were 14,000 objections to the Greater Dublin Drainage (GDD) project, which includes a large treatment works at Clonshaugh and which was granted permission by An Bord Pleanála on Wednesday. It will serve north Dublin and south Fingal by 2026 and ease pressure on Ringsend as it will cater for a population of 500,000.
The north-western parts of the Ringsend catchment will be diverted to the new plant, freeing up capacity and alleviating pressure within the existing drainage system and at the treatment plant.
Noel Byrne of the EPA’s management of waste water enforcement team acknowledges the quality of the treated waste water going into the bay will improve as upgrade works proceed, though Ringsend “is not expected to start meeting the required standards until the end of 2022 at the earliest”.
With the Clonshaugh facility coming on stream he is hopeful it will provide the necessary headroom for the Dublin region. Given population projections, however, it is probable that at some point Ringsend will need even further expansion, he concedes.
The poor performance of the plant is such that the possibility of substantial fines under the EU Waste Water Directive lurk in the background. If there is further slippage in that 2022 compliance date, the Commission is likely ask the EU Court to impose substantial fines, he adds.
Irish Water has signalled intent. Its investment in wastewater infrastructure will be almost €400 million in 2020, matching investment in drinking water for the first time. This, it says, coincides with more projects such as Ringsend and GDD moving from the design and planning stages through to construction.