A burst has occurred on a mains water pipe delivering water from the Pollan Dam to South Inishowen.
Crews working on behalf of Irish Water and Donegal County Council are on site and are working as a matter of priority to repair the burst as quickly as possible.
As a result of this incident, a number of areas will be without water, including Fahan, Burnfoot, Inch Island, Bridgend, Muff, Burt, Mullaney and parts of Newtowncunninghan.
Properties located at higher levels in the Lisfannon, Newtowncunningham, Manorcunningham, Carrigans and St Johnston areas are likely to experience water outages and other houses in those areas may experience reduced pressure or loss of water.
Irish Water apologises to all customers for the disruption caused by this incident.
Updates on the disruption will be provided as soon as they are available on the service and supply section of the Irish Water website, www.water.ie or by calling 1850 278 278 for information.