Groundwater data and maps include:
County Groundwater Protection Scheme Reports
Groundwater Body Descriptions
Groundwater Flood Data
Groundwater Karst Data
Groundwater Recharge
Groundwater Resources (Aquifers)
Groundwater Vulnerability
Groundwater Wells and Springs
Group Scheme and Public Supply Source Protection Areas
Hydrostratigraphic Rock Unit Groups
Open Topographic Data Viewer (Lidar)
Subsoil Permeability
A Groundwater Protection Scheme provides guidelines for the planning and licensing authorities in carrying out their functions, and a framework to assist in decision-making on the location, nature and control of developments and activities in order to protect groundwater.
Groundwater Protection Schemes are county-based projects that are undertaken jointly between the GSI and the respective Local Authority.
The reports summarise the hydrogeology, aquifers, groundwater vulnerability and the groundwater use in a county at the time of the study.
Groundwater Water Quality Reports give an overview of the main water quality issues in each county at the time of reporting.
Groundwater bodies are subdivisions of large geographical areas of aquifers so that they can be effectively managed in order to protect the groundwater and linked surface waters.
The winter of 2015/2016 saw the most extensive groundwater flooding ever witnessed in Ireland. The lack of data on groundwater flooding and fit-for-purpose flood hazard maps were identified as serious impediments to managing groundwater flood risk in vulnerable communities. Geological Survey Ireland - in collaboration with Trinity College Dublin and Institute of Technology Carlow - initiated the groundwater flood project GWFlood to address these deficits. The resulting project products include a Groundwater Flood Maps Viewer showing historic and predictive groundwater flood maps, a Groundwater Level Data Viewer showing live groundwater hydrometric data and a comprehensive project report available below.
Karst is a landscape with distinctive landforms that develop on rock types that are readily dissolved by water. In Ireland, karstification mostly occurs in limestone regions.
This karst dataset contains mapped karst landforms in Ireland including: boreholes, caves, dry valleys, enclosed depressions, estavelles, springs, superficial solution features, swallow holes and turloughs. It is displayed as point features, locating the centre (or, in the case of a cave, the entrance) of the karst landform, and records details of the landform’s dimensions and functioning.
Coordinate System: Irish Transverse Mercator / ITM
Karst Traced Underground Connections
Water tracing involves ‘tagging’ water to see where it goes. The karst traced underground connections dataset is an inventory of known water dye trace studies and results in Ireland. It is displayed as straight-line paths from input to emergence, with an arrow indicating direction of flow.
Coordinate System: Irish Transverse Mercator / ITM
The groundwater recharge map provides an estimate of the average amount of rainwater that percolates down through the subsoils to the water table over a year. Scale: 1:40,000
Coordinate System: Irish Transverse Mercator / ITM
An aquifer is an underground body of water bearing rock or unconsolidated materials (gravel or sand) from which groundwater can be extracted in useful amounts.
There are two main types of aquifer in Ireland – bedrock aquifers, and sand and gravel aquifers (<5%).
GSI Aquifer classesare divided into three main groups based on their resource potential (Regionally or Locally important, or Poor), and further subdivided based on the type of openings through which groundwater flows (through fissures, karst conduits or intergranular). There are nine aquifer categories in total.
Aquifers Bedrock
In bedrock aquifers the groundwater is stored in and travels through fractures, joints and other weaknesses in the rock.
This is a polygon dataset containing nine Bedrock Aquifer classes. Scale: 1:100,000
Coordinate System: Irish Transverse Mercator / ITM
Aquifers Sand and Gravel
In sand and gravel aquifers groundwater is stored and flows between the sand and gravel grains.
This is a polygon dataset containing two Sand and Gravel Aquifer classes. Scale: 1:40,000
Coordinate System: Irish Transverse Mercator / ITM
The Groundwater Vulnerability map outlines how susceptible areas are to groundwater contamination. Scale: 1:40,000
Coordinate System: Irish Transverse Mercator / ITM
This dataset contains records of boreholes, dug wells, springs, and ground site investigations.
Coordinate System: Irish Transverse Mercator / ITM
Groundwater sources, particularly public, group scheme and industrial supplies, are of critical importance in many regions.
Public Supply Source Protection Areas
The dataset comprises Source Protection Areas (SPAs) around groundwater abstraction points that are managed by Irish Water to supply Public Water Supply Schemes across Ireland. The objective of the SPAs is to provide protection by placing tighter controls on activities within all or part of the zone of contribution (ZOC) of the source. The Zone of Contribution (ZOC) is the land area that contributes water to the well or spring. Scale: 1:15,000 – 1:20,000
Coordinate System: Irish Transverse Mercator / ITM
Source Protection Zone Reports
Group Scheme Preliminary Source Protection Areas
The dataset comprises Zones of Contribution (ZOC) to groundwater abstraction points that supply Group Water Schemes across Ireland that are affiliated to the National Federation of Group Water Schemes and that supply more than 15 people. The ZOCs are preliminary protection areas around groundwater abstractions, but are not full Source Protection Areas.
Scale: 1:15,000 – 1:20,000
Coordinate System: Irish Transverse Mercator / ITM
This Hydrostratigraphic Rock Unit Groups map is a reclassification of the 1:100,000 bedrock geology map into 27 ‘Rock Unit Group’ categories that, within them, have similar hydrogeological properties. Scale: 1:100,000
Coordinate System: Irish Transverse Mercator/ITM
The Open Topographic Data Viewer provides access to processed LiDAR data in raster format from Geological Survey Ireland, Department of Culture, Heritage and the Gaeltacht, Discovery Programme, Transport Infrastructure Ireland and New York University.
The aim of this viewer is to host LiDAR from all interested government and non-government organisations and to build up a mosaic of available data across the country.
The high resolution raster data in the form of Digital Terrain Models and Digital Surface Models can be downloaded from the viewer.
The Groundwater Subsoil Permeability map classifies how easy water can infiltrate subsoils downwards at any point in the land surface. Permeability across the country is classified as either ‘High’, ‘Moderate’ or ‘Low’. This map is used to determine groundwater vulnerability categories. Scale: 1:40,000
Coordinate System: Irish Transverse Mercator / ITM