Catchment News

Environmental sensitivity mapping: supporting assessments and planning decisions in Ireland

The Strategic Environmental Assessment (SEA) Directive requires the assessment of potential environmental impacts resulting from the implementation of plans (e.g. river basin management plans, county development plans) and programmes (e.g. for waste management). The overall goal of SEA is to support sustainable development by incorporating environmental considerations into decision-making.

This is commonly done by determining the vulnerability or sensitivity of the areas likely to be affected by the plan/programme. Informed by this, recommendations are made to avoid or mitigate any potential significant environmental effects. Environmental sensitivity describes the susceptibility of natural resources (e.g. habitats, water bodies) to human-induced changes such as landuse modifications that may cause their degradation. Analysing a region’s characteristics that make it susceptible to change provides a valuable starting-point in plan-making, helping to direct developments to the most appropriate location.

The growing availability of spatial data and technological developments are resulting in a greater uptake of online GISbased decision support tools in planning and decision-making. Building on these advancements, a team of researchers led by UCD School of Geography, in collaboration with the All-island Research Observatory (AIRO) at Maynooth University, have developed an Environmental Sensitivity Mapping (ESM) web-tool to support SEA and planning decisions in Ireland.

Figure 1. Strategic Environmental Assessment (SEA) thematic groupings of data
on the left menu, and bedrock aquifer map showing detailed attribute information
through a pop-up query window.

The ESM web-tool centralises access to well over 100 environmental datasets grouped by SEA themes, including water, allowing planners to rapidly and efficiently examine environmental considerations within their plan area. It also includes a bespoke and innovative analytical widget that enables creating plan-specific environmental sensitivity maps, without the need for specific GIS skills or expertise. Users can select a range of datasets from each SEA theme to include in the analysis (Figure 1), as relevant to the plan/programme under assessment. These datasets can be weighted to determine their relative importance and, in this way, capture stakeholder concerns/opinion (for example, on the importance of protecting nutrient sensitive water bodies), facilitating public consultation requirements in SEA. The final output provides an environmental sensitivity index map for the selected area (Figure 2) – which can help anticipate potential landuse conflicts to inform planning decisions.

Figure 2. Sample Environmental Sensitivity Map (ESM) for the Shannon Estuary. The ESM widget allows creating sensitivity maps at a water management unit level. This particular map has been created using the environmental variables shown in the map layout below (Figure 3).

The ESM web-tool is a publicly available, robust and innovative solution that can lead to more effective environmental assessments and, in turn, better plan-making in Ireland. It has already informed the National Planning Framework and the Regional Spatial and Economic Strategies, as well as various other applications at local level.

Ainhoa González

Learn more:

For more information on the web-tool, project background and
informative video on GIS and SEA, visit – see
Start Mapping to access the web-tool.

Acknowledgements: The ESM web-tool is a collaborative public
sector data project between UCD School of Geography (concept and
design) and AIRO (analytics and mapping). The research was funded
and supported by the Environmental Protection Agency and the
web-tool is hosted by the Ordnance Survey Ireland on their GeoHive,
the State Geospatial DataHub.

Figure 3: Sample Environmental Sensitivity Map (ESM) layout illustrating the environmental criteria brought into the sensitivity analysis. These criteria are to be contextualised to the issues of the plan/programme under assessment for a meaningful analysis.

Who is involved?

Quite simply, everyone in Ireland has a role to play. This can be from something as simple as making sure you don’t pollute your local stream, or a local community working together to establish a Rivers Trust to enhance the rivers and lakes in their area, to a Government Department or Agency helping a Minister implement a new policy to help protect and enhance all our water bodies.

This website has been developed and is maintained by the Environmental Protection Agency, and is a collaboration between the Department of Housing, Planning and Local Government, the Environmental Protection Agency, and the Local Authority Waters Programme.


Local Authority Waters Programme

The Local Authority Waters Programme coordinates the efforts of local authorities and other public bodies in the implementation of the River Basin Management Plan, and supports local community and stakeholder involvement in managing our natural waters, for everyone’s benefit.


Environmental Protection Agency

The EPA is responsible for coordinating the monitoring, assessment and reporting on the status of our 4,842 water bodies, looking at trends and changes, determining which waterbodies are at risk and what could be causing this, and drafting environmental objectives for each.


Department of Housing, Local Government and Heritage

The Department is responsible for making sure that the right policies, regulations and resources are in place to implement the Water Framework Directive, and developing a River Basin Management Plan and Programme of Measures to protect and restore our waters.