Irish Water has confirmed that the countrywide hosepipe ban introduced earlier this month will remain in place until the end of August.

Night-time pressure restrictions in the Greater Dublin area will remain in place for another two weeks.

The utility company said it is the view of the water engineering experts within local authorities and Irish Water that the situation will remain critical up to and possibly beyond mid-August.

The Board of Irish Water reviewed the latest available data on water usage and the condition of the raw water sources around the country and confirmed the hosepipe ban until 31 August.

The most severe conditions continue to be in the east and south, where the rivers, lakes and groundwater tables are at record lows, Irish Water said in a statement.

Latest Office of Public Water data shows over half of rivers are at levels that were previously unheard of in July, it added.

It comes as a status yellow rainfall warning has been issued for 16 counties as the recent sunny spells looks set to break.

Thundery downpours may bring up to 40mm of rainfall to all of Leinster, Cavan, Monaghan, Donegal and Waterford.

The warning comes into effect at 9pm today and will be in place until 9am on Saturday.

Met Éireann figures show that in the east of the country only about a quarter of the rainfall usually expected for the three months of May, June and July has fallen so far this year.

Irish water is particularly concerned about the implications if larger amounts of rain do not fall soon. 

The company is engaged in ongoing contingency planning with regard to what actions it may have to take if the situation does not change.

It is keen not to disrupt the business, hospitality or tourism sectors during the first two weeks of August, which is the peak tourism season. 

Irish Water is planning to review the night-time water restrictions in the Dublin area when the two-week period is over.

The company is also growing increasingly concerned about the low level of water in the Poulaphouca Reservoir, one of the three key reservoirs supplying the population of Dublin with drinking water sourced from the River Liffey.

It is also concerned about the risks posed by the lack of rain and water flow for the waste water systems.

The lack of water means that a build up of rags and grit and other debris in some locations may result in localised blockages and drain overflows if heavy downpours of rain occur in the coming days.

Looking ahead, Irish Water is also becoming quite concerned about the fact that schools and colleges - which are very heavy users of water - will be reopening before the end of August and this will place an even greater demand on the water system which may not have recovered by that stage.

Soil moisture deficit data from Met Éireann indicates that in many parts of the east as much as 90mm of rainfall would still be required to replenish the soils before the water would start to fill up into the reservoirs. 

Yet the total amount of rainfall recorded at Met Éireann's synoptic weather station in Dublin's Phoenix Park has amounted to just 50mm since the start of May, which is a three-month period. 

All of this suggests that heightened concerns about the supply of water to the Greater Dublin region are now likely to persist for many weeks ahead regardless of what happens with the weather.