Irish Water has extended the national hosepipe ban for another month, until August 31.
Night time restrictions in the Greater Dublin area have also been extended for another two weeks.
Irish Water says the situation will remain critical up to and possibly beyond mid-August.
It comes as Met Éireann has issued a status yellow rainfall warning for Leinster, Cavan, Monaghan, Donegal and Waterford, which comes into effect at 9pm.
But Kate Gannon from Irish Water says it is not enough to restore supplies.
She said: “We would really need 2-3 weeks of heavy rainfall to get our sources back up.
“One weekend of rain, even if it is a lot of rain will not give us enough water that we need nationally to help all our sources recover.”