A disruption to the water supply is expected across Mahon, Blackrock and Ballintemple on Wednesday night.
Irish Water is carrying out water main improvement works on the Skehard Road.
As a result, there may be a disruption to water supply from 11.30pm on Wednesday until 4am on Thursday morning.
Homes and businesses in Mahon, Ballintemple, Blackrock, Beaumount, Monahan Road and The Marina could be impacted.
Following these improvement works water supply may take two to three hours to return as water refills the network.
Irish Water said the disruption is unavoidable as the watermains in the Skehard Road area do not allow isolation from the primary trunk main and therefore to allow new water mains to be connected to the network a greater area shutdown is required.
Until full supply is resumed Irish Water advises customers to:
Switch off any gas, oil or electrical appliances that you use to heat your water such as an immersion heater.
Not use central heating systems while the water is off
Avoid flushing the toilet
When the water is restored it is advisable to:
Slowly run the cold water kitchen tap until the water clears
Do not use your washing machine, dishwasher, shower or similar appliance until the water clears.