Night-time water restrictions will be put in place from 10pm to 5am across the city centre and in 33 suburbs in Dublin and Wicklow from Monday.
Pressure will be cut across these areas for seven hours each night, with some households having only a "trickle" at the kitchen sink for these times.
Most of the affected suburbs are on the southside of the city, with just nine northside suburbs due to be hit with restrictions. While the restrictions will stretch through south Dublin all the way to Bray in north Wicklow, Beaumont will be the most northerly suburb affected.
Water restrictions in the greater Dublin area will be reviewed in a week by Irish Water.
The company said the restrictions will be reviewed next Monday. This morning senior management met to discuss the water network difficulties, brought on by the recent high temperatures and sustained drought.
The management team reviewed supply levels to over 100 under-pressure water schemes across the country.
Since a critical high point in late June, where demand outstripped the supply capacity of the Dublin network, the amount of water being drawn down by homes and businesses has declined.
A national ban on households using their garden hosepipe introduced at the start of the month is in place until the end of July.
The greater Dublin water network can supply 610 megalitres of treated water a day. Some 590 megalitres was used on July 3rd; this dropped to 568 m/l a day by July 9th and was down to 559 m/l yesterday.
Some 3,500 restaurants stand to be affected by the Dublin night time water restrictions. Most residential suburbs affected are in Dublin, but Bray, Co Wicklow, is also included in the conservation measures.
Pressure will be cut to homes and businesses for seven hours each night from 10pm until 5am, Irish Water has said. Most customers will experience low night-time pressures but “no loss of supply”.
Supply to some customers on high ground and at the remote end of networks may reduce to a “trickle” at the kitchen sink.
Irish Water have said a sustained period of rainfall over two weeks would be needed to address supply problems. The knock-on effects of the drop in supply due to the exceptional period of warm weather may affect the water system into the autumn.
The next level of restriction would see the reduction in supply extended from 9pm to 7am, but Irish Water said this is not currently planned.
