Irish Water said it has incident plans in place and crews on standby to deal with the effects of Storm Ophelia.
"Irish Water recognises that the predicted conditions are likely to result in power outages at critical water and wastewater installations which could compromise service delivery. Heavy rainfall may also increase the risk of flooding," the company said.
"Power outages may impact the operation of our water treatment plants which would compromise the safety of drinking water. Where risk arises, working with the HSE, Irish Water will impose precautionary Boil Water Notices as necessary.
"Irish Water is collating information on outages and other issues and will be updating our website constantly during this crisis. We envisage that crews will be unlikely to be able to respond to breakdowns in plants until it is safe to do so and this may lead to a loss of service for a period. However Irish Water and Local Authorities crews will respond as quickly as possible to restore services when it is safe to do so.
"If you have issues with your water supply please view our service supply map on water.ie, visit twitter at @IWCare or call us on 1850 278 278. We would appreciate if members of the public would only call if there is an emergency as there are staff shortages in our call centre in Cork today. If there is a high volume of calls there may be some delay in getting through, we are grateful for your patience and cooperation."