For the second successive week, freak weather has caused alarm and widespread flooding in parts of Ireland, with August set to go down as the wettest in living memory.

Notices to householders to boil their drinking water were issued by several councils amid fears that floods as rivers burst their banks may have contaminated supplies.

In the midlands, parts of Portarlington were flooded, and in Carlow more than 100 residents were moved from their homes by boat and heavy tractor units.

In the north west, emergency services were called out to clear massive landslides near Arigna on the Sligo-Roscommon border that cut off a mountain road and a scattered community for a night. Householders queued in the streets of Sligo Town and the nearby village of Rosses Point on Tuesday for special day-long deliveries of drinking water by firemen amid fears of contamination in the public supply system.

The emergency service was put into operation after freak weather and flooding when rivers burst their banks, caused discoloration in the water and raised concern over the normal supply.

Local council chiefs said tests on the discolored water proved negative for microbiological contamination, but the emergency measure was introduced as a precaution until the discoloration has abated.

Carlow was the worst hit, and Environment Minister John Gormley visited the town to pledge that a much-delayed $42 million contract for flood defenses for the town would proceed as quickly as possible.

Having toured the area and spoken to some of the flood victims, Gormley said it was clear that climate was changing, weather patterns were changing and Ireland will see more rainfall in future. He said, "As a consequence, we have to plan accordingly, and that is why in the next few weeks I will be issuing new guidelines in relation to flooding, and I hope that in the future building on flood plains will become a thing of the past."

At one stage the waters in Carlow reached six feet where the River Barrow burst its banks and flooded three new apartment blocks. The electricity supply to the apartments was cut off for safety reasons and residents evacuated.

One evacuated couple, Ger Scully and Barbara Brennan, who live with their child in one of the ground-floor flats said they were going to move away from the area.

"This is the second time this happened this year. All our belongings are destroyed. We have been out buying clothes for the baby. We just cannot live here any more. We will have to move," Brennan said.