Plans to build a €500m sewage treatment plant in north Dublin have been approved by An Bord Pleanála.
The decision follows months of objections from locals who have warned that the huge new plant will have a “catastrophic effect” on residents and wildlife in the region.
The development includes a new sewage treatment plant just off the Malahide Road, an orbital sewer from Blanchardstown and an outfall pipeline through the Baldoyle Estuary into the Irish Sea.
Residents have warned that the plant will be four times the size of Croke Park and will have the capacity to pump 300 million litres of water a day into the sea off Ireland’s Eye.
Sabrina Joyce-Kemper, spokeswoman for the ‘Solution not Pollution’ campaign, said residents are ready to take legal action to block the plans.
"We accept that the sewage network is under pressure and we are willing to help Irish Water find another solution, but this isn't it,” she said.
“Our experts have come up with a very workable solution and we believe they need to consider more sustainable and modern alternatives.”
Irish Water said the amount of wastewater generated in the Greater Dublin Area in the next 30 years is likely to increase by 30% due to population growth and increased commercial activity.
It said adequate wastewater treatment capacity is vital in terms of protecting public health, safeguarding the environment and facilitating social and economic growth.
The utility’s Head of Asset Management Seán Laffey said the project is “vital for residential and commercial development across north Dublin and south Fingal.”
“New homes and businesses can only be built with new wastewater infrastructure to support them,” he said.
“GDD will also alleviate pressure within the wider wastewater network.
“It will help to ensure that the wastewater generated every day in our homes, schools and workplaces is treated safely, in compliance with the EU and national wastewater treatment regulations.”
The new pipeline will run from Blanchardstown to a new pumping station at Abbotstown and on to the new treatment plant.
The sewage will be pumped from the plant into the Irish Sea through a 6km pipeline through the Baldoyle estuary.
‘Solution not Pollution’ spokesman Philip Swan said the Dublin coast is already under huge stress.
“We utterly reject this decision,” he said.
“This plant will treat sewage for over half the population of Ireland – discharging waste into a 20km stretch of water in Dublin Bay.
“Over 30,000 people have objected to this plant because it poses risks to people’s health and to the physical and marine environment of Dublin Bay on which fishing and tourism depend.”
Ms Joyce Kemper said the campaign has the support of a “panel of experts, marine and microbiologists” all of whom “agree this plan will kill life in the sea.”
“Heavy metals will accumulate in shellfish; habitat will be destroyed, during both the construction process and operational stages.
“We aren't just being NIMBY [Not In My Back Yard] about this.
“It’s not just our back yard – this is the Irish Sea we are talking about, it’s everyone’s back yard.
“The sea is a finite resource and deliberate pollution not only impacts habitats and marine life – but tourism, fishing and human health.”
Campaigners are also calling on Irish Water to reveal the full cost of the project.