Dáil Éireann debate -
Wednesday, 6 Mar 1996

Vol. 462 No. 6

Written Answers. - Dublin Bay Pollution.

Ivor Callely

Question:

41 Mr. Callely asked the Minister for the Marine the estimated amount of sewage that will be dumped or pumped, treated or untreated, into Dublin Bay in 1996; the likely impact of this sewage; and if he will make a statement on the matter. [5061/96]

Minister for the Marine (Mr. Barrett)

I wish to inform the House that the Department of the Marine controls dumping of sewage sludge at sea and the Department of the Environment controls pumping of sewage into the sea.

Under the Dumping at Sea Act, 1981, the Minister for the Marine may grant or refuse to grant a permit authorising dumping at sea operations. Dublin Corporation currently holds an annual permit granted by my Department permitting the disposal of up to a maximum of 340,000 tonnes of sewage sludge at sea during 1996 with a maximum of 2,000 tonnes to be dumped per day. Three trips are normally made to the site per week with approximately 2,000 tonnes being disposed of on each trip. The dump site is located some 14 miles south-east of the Kish Lighthouse in Dublin Bay.

The dump site is dispersive in nature and monitoring carried out in 1993 revealed that there was no significant impact on sediment fauna in the area. According to international practice, monitoring of such sites is recommended at approximately five year intervals and the site will be resurveyed in 1998. Under present disposal conditions environmental problems are not anticipated at this site.

This is the only authorised dumping of sewage sludge at sea in Ireland. The dumping of sewage sludge at sea will be prohibited internationally under the Convention for the Protection of the Marine Environment (OSPAR) from 31 December 1998. The new Dumping at Sea Bill, 1995, will prohibit such dumping after that date. Dublin Corporation's plan for alternative disposal methods has been approved by the Department of the Environment and work on the implementation of the plan to switch to land based disposal after 31 December 1998 is on target.

Discharges of sewage into the sea from land are controlled by the Department of the Environment which has advised me that Dublin Corporation estimate that approximately 333,000 cubic metres per day of sewage is pumped into Dublin Bay. Of this figure, approximately 67,000 cubic metres per day is untreated, the balance (266,000 cubic metres per day) receives primary treatment.

The bulk of Dublin's waste water is discharged at two locations, Ringsend and Howth. No treatment is provided at Howth other than the screening of the discharge, while primary treatment is provided at Ringsend which also serves Dún Laoghaire. The sludge arising from the primary treatment process is thickened prior to dumping in other parts of Dublin Bay.

EU Directive 91/271/EEC, the EU Urban Waste Water Treatment Directive, was adopted in 1991 and came into force on 30 June 1993. The directive sets down minimum requirements and standards for the collection and treatment of sewage. Under the requirements of the Environmental Protection Agency, 1992, (Urban Waste Water Treatment) Regulations, 1994, which transposed the mandatory requirements of EU Directive 91/271/EEC into Irish law, Dublin's sewage discharges must receive secondary treatment by the year 2000.

Dublin Corporation is at present planning the construction of expanded facilities at Ringsend treatment works to provide secondary treatment and sludge treatment and management to comply with the year 2000 deadline. It is currently estimated that the cost of these works will be in excess of £200 million. The works are being funded with the assistance of the EU Cohesion Fund.