Only one beach in Northern Ireland missed the minimum standard for bathing water quality this year, it was revealed today.
Ballyholme, Co Down, was the sole failure as improved results saw 23 areas reach mandatory limits.
Northern Ireland Water (NIW) director George Butler said he was pleased to see progress despite the wet summer.
"Whilst these results demonstrate that our investment in wastewater systems is making a difference, we acknowledge that there is still work to be done."
The Northern Ireland Environment Agency recorded results from June to mid-September this year. It found 10 beaches met the stringent guideline standard. The number reaching the mandatory standards increased from 21 in 2007.
Mr Butler said Ballyholme was affected by the summer's poor conditions.
"Heavy rain increases run off from roads, land and the sewerage system into streams which then discharge on to the beach," he added. "We have commenced a £3.5 million project to improve the sewerage network in Ballyholme that will bring significant benefits, including improving bathing water quality in the area."
He said NIW planned to invest £490m by 2010 on improvements to the sewerage network and water treatment works.
Work is being carried out on treatment works on the north coast, Belfast north shore, Larne, Portaferry and north Down.
PA