An Bord Pleanala confirmed earlier this week that a decision on the monster sewage treatment plant in Clonshaugh has been deferred for three months.

A ruling on the controversial €500 million Irish Water project was due on June 28 but this has now been put back until Friday, September 27.

A spokesperson for the planning appeals board said the inspector was still compiling a report on the massive development, dubbed the Greater Dublin Drainage Project, on the back of a four-day oral hearing held in March.

Objectors have welcomed news of the delay as they continue their opposition to the project which would see an outfall pipe located just 1km off Ireland’s Eye.

As reported in Dublin Gazette, locals have vowed to intensify their campaign against the plant and are prepared to take their case to the European courts if necessary.

Environmentalists and marine experts have warned that the plant could have catastrophic consequences for Dublin Bay – putting at risk its status as the only UNESCO Biosphere in a capital city in the world.

In addition to the thousands of submissions warning against the project, a ‘Solution Not Pollution’ petition online has garnered more than 4,000 signatures.

Microbiologist Edward Bourke also warned that building a pumping station and sewage storage tanks at Abbotstown in Blanchardstown, close to the national sports campus, a hospital and a hospice, raised a number of concerns.

He said: “The scheme has the potential to cause dreadful odours particularly at the tanks at Blanchardstown and at the treatment plant at Clonshaugh.

“There are few controls on these odours other than in terms of planning permission and specific tests for odour and specific odour mitigation measures are largely ignored.

“When tanks are forcefully aerated, they can throw up spray and unless this is properly filtered this can contain bacteria and viruses which can be windborne for significant distances.”

Meanwhile, the Environmental Protection Agency (EPA) is set to conduct an inspection at the Ringsend wastewater treatment plant after a brown plume discharged into Dublin Bay.

Irish Water informed the EPA about the plume on Tuesday but reported no malfunction at the plant and said the facility