Concerns over Dublin Bay dumping plan

Major environmental concerns have emerged over plans to dump hundreds of thousands of tonnes of tunnelling waste in Dublin Bay.

Dublin City Council has published a notice that it had applied for a licence for the project which would see up to 824,000 tonnes of “spoil” – mainly crushed rock – dumped at a location 3km off Howth Head.

If licensed, spoil material bored from the ocean floor will be taken by barge to the dumping site and disposed of at the rate of one to two loads a day over three years beginning in 2014. Council officials say this type of material had been dumped near the Burford Bank site in the past and the project posed no environmental threat.

A licence application has been forwarded to the Environmental Protection Agency, details of which have now been published. The material would be the by-product of a 9km tunnel bored to extend the Ringsend waste water treatment plant and expand its capacity from a population equivalent of 1.64 million to 2.1 million.

However Independent councillor Mannix Flynn said the plans would spark a massive political backlash. “It’s akin to landfill and that has to be frowned upon. It is general disregard for a universally accepted beauty spot,” he said.

Dangerous impact

It has raised considerable concern at the country’s largest diving club, the Curragh Sub Aqua Club in Sandycove, Dublin, which said it would have a dangerous impact on water visibility and wildlife. The council said the site in question, which reaches an average depth of 19m (62ft), is not used by divers.

But dive instructor and former engineering consultant Peadar Farrell, who is to formally object to the project, said the drilled limestone would form a “cake” on the ocean floor and disperse for miles underwater.

An Bord Pleanála has previously said it was satisfied the dumping would not impact on six special protection and conservation areas in the surrounding coastline.

However Mr Farrell said water visibility is affected by dumping at sea or through pipe laying and that the club had previously lost a member as a result.

“Diving in such conditions is dangerous and the dive is usually cut short when the two divers lose each other and have to surface.”