Yes, many rural houses in Ireland are supplied by a private well or a group water scheme rather than the public mains, and this is generally acceptable to planning authorities provided a safe, adequate water supply can be demonstrated. Planning applications for a house on a private supply typically require evidence such as a well report or connection confirmation from a group scheme.
It is common in rural Ireland to build and live in a house that is not connected to the public mains water supply, relying instead on a private well, a group water scheme (a shared local supply, often run by a community group or co-operative), or occasionally rainwater harvesting supplemented by another source. Local authorities generally accept this where mains water is not available or not economically feasible to extend to the site, but the planning application will usually need to demonstrate that a safe and sufficient water supply is achievable.
For a private well, this typically means providing information on the well's location relative to sources of contamination such as septic tank percolation areas, farmyards or other wells, along with evidence of adequate yield and, in many cases, a water quality/potability test once the well is drilled. Planning conditions commonly require the well to be positioned a minimum distance from any wastewater treatment system on the site or on neighbouring land, reflecting guidance on separation distances between wells and septic tanks.
Where a group water scheme serves the area, the applicant usually needs to show that connection to the scheme is available and that the scheme operator has confirmed capacity; this is often simpler than developing a new private well. In all cases, the choice of water source interacts closely with the site's wastewater treatment arrangements, since both need to be designed and positioned together to avoid contamination risk, and this is typically assessed as part of the planning application by the local authority.