Families in a west Dublin housing estate were told to prepare for evacuation this morning after a burst water main flooded the streets.
Rapidly rising water invaded the porches of some houses and submerged the gardens of the Ashwood Estate in Clondalkin at around 5.30am.
Four cars were also wrecked by flood water in the dramatic incident.
Only when the water was covering the doorsteps of some homes and lapping at the front doors was disaster avoided and the mains supply turned off, more than an hour after the fault was spotted.
Several units of Dublin Fire Brigade as well as gardai worked to stop the rising water and alert locals.
The Fonthill Road was also shut to traffic as rising water flooded it and diversions were put in place from 7am.
In a major clean-up operation, fire brigade crews worked up to their waists in water to clear blocked drains to try to drain the estate of flood water.
Only then could work begin on trying to find the source of the mains fracture.
Locals told of how the rising water caused a power cut, and gardai had to bang on their doors to wake them and tell them to prepare to leave their homes.
"I didn't know what was happening when I saw them at my door at that hour, and then I saw the flood water rising rapidly," said Michael Roche.
"I put a sheet of wood across my front door and the water still got into my porch, he added.
Worst affected were the Lawlor family next door, whose cars were destroyed.
"We live at the end of the road in the lowest part, and the water just came up the driveway and into the porch," Tony Lawlor told the Herald.
"We've had trouble with drainage in this part of the estate for years but I've never seen it fill up this quick," he added.
"The storm drains are probably all blocked with leaves, but when it rains heavily they get backed-up. Something needs to be done to make them drain faster," Tony explained.
Kirsty Bang lives across the road from Tony, and she too said she had to watch helplessly as the water level rose.
"The gardai called at around 6.30am and we watched as the water kept getting higher," she said. "It came right over the top step and we had to put towels and blankets against the front door in case it got higher, but thankfully it didn't.
"Our back garden was totally submerged, the wheelie bin was floating around at one stage and there was nothing we could do," she added.
Workmen using spades, brushes and poles worked to unclog the storm drains and slowly the water started to drain away.
A large tanker was then supplied by South Dublin County Council to suck up the remaining water before pumping it down a nearby manhole where it flowed away.
But the clean-up operation for the residents was likely to take some time.
"I suppose I'll have to get in touch with my own insurance company about the damage to the cars in the driveway," said Tony Lawlor.
"I'm not sure if that will affect the no-claims bonus or not. It's a nightmare," he added.
Irish Water was contacted by the Herald this morning and a spokesperson said it was investigating the incident and could not comment until more information was available.