Freshwater and Marine

The EPA works with others to monitor and assess the health of our rivers, lakes, estuaries and coastal waters under the Water Framework Directive.

Water quality in Ireland

What do you need to know about water quality?

Water Quality in Ireland

Clean water is essential for people, wildlife and the environment. While many of Ireland's waters remain in good condition, the overall quality of our rivers, lakes, estuaries and coastal waters has declined in recent years.
Just over half  of our surface waters are in satisfactory ecological health - being in either good or high ecological status. Excess nutrients, particularly nitrogen and phosphorus from agriculture and wastewater, remain the main pressure affecting water quality.

 

Read more about the EPA's assessments of water quality and agriculture.

Nitrates and phosphorous

Excess nutrients, particularly nitrogen and phosphorus, remain one of the main pressures affecting water quality in Ireland. Nutrients from agriculture, wastewater and other human activities can enter rivers, lakes, estuaries, coastal waters and groundwater. When nutrient levels become too high, they can cause excessive growth of algae and aquatic plants, reducing oxygen levels and harming aquatic life such as insects and fish.

Water quality monitoring shows that nutrient levels remain too high in many parts of the country, particularly in areas vulnerable to nitrogen losses. While some local improvements have been recorded, overall water quality has shown little improvement in recent years. Continued action to reduce nutrient losses is needed to protect and restore water quality.

 

Read the latest Monitoring & Assessment: Freshwater & Marine Publications | Environmental Protection Agency

 

 

What's being done?

The Water Framework Directive

Our rivers, lakes, estuaries, coastal and groundwaters are assessed under the EU Water Framework Directive (WFD). This EU law came into effect in December 2000. Having a single European framework to assess water quality allows us to compare our results across Europe.

Our surface waters are classified into five quality classes (status) under the WFD: High, Good, Moderate, Poor and Bad.

"High" is when the water is unpolluted, and "Bad" is when the water is highly polluted. Our ground waters fall into two quality classes (status) under the WFD: "Good" and "Poor".

The WFD allows us to see where actions are needed to achieve "Good" status or to protect "Good" or "High" status where it already exists. It also helps us identify what actions need to be taken. We can restore rivers to Good and High status by using targeted actions and measures to reduce the impact of human activities.

The River Basin Management Plan

The River Basin Management Plan outlines Ireland's policy response to the challenge of protecting and restoring water quality. The plan is published on a 6 year cycle by the Department of Housing, Local Government and Heritage. It includes targeted actions and measures to protect and restore water quality.

Learn about the River Basin Management Plan 2022-2027

Featured reports on Freshwater & Marine

in: Freshwater & Marine
Bathing Water Quality in Ireland in 2025 Front Cover
Bathing Water Quality in Ireland 2025

Bathing Water Quality in Ireland 2025

The EPA Bathing Water report sets out bathing water quality at Ireland's beaches during the summer of 2025 bathing water season.

Cover image for the EPA report “Water Quality in 2025: An Indicators Report”. The image shows a clear coastal landscape with rocky shoreline in the foreground, shallow tidal pools, and calm blue sea stretching towards distant mountains under a bright, cloudless sky. A small wooded headland appears on the right. The EPA (Environmental Protection Agency) logo is positioned at the top.
Water Quality in Ireland 2025 - An Indicators Report

Water Quality in Ireland 2025 - An Indicators Report

This report looks at how Ireland’s water quality has changed in 2025, using the latest monitoring data for rivers, lakes, groundwater, estuaries and coastal waters.

water quality NP 2025 report cover
Water quality monitoring report on nitrogen and phosphorus concentrations in Irish waters 2025

Water quality monitoring report on nitrogen and phosphorus concentrations in Irish waters 2025

This report provides an update on the results of water quality monitoring to support the assessment of the impact of the nitrates derogation on Irish waters, as required under Regulation 39 of the European Union (Good Agricultural Practices for the Protection of Waters) (Amendment) Regulations.

Water quality In Ireland 2019-2024 Cover
Water Quality in Ireland 2019-2024

Water Quality in Ireland 2019-2024

This report sets out the latest assessment of the health of Ireland’s rivers, lakes, canals, groundwaters, transitional (estuaries) and coastal waters.

The cover of the report 'Irelands National Water Quality Monitoring Programme 2022–2027' . The image on the front is of a small ribbed inflatable boat beside a large lake with small mountains in the background.
Ireland’s National Water Quality Monitoring Programme 2022–2027

Ireland’s National Water Quality Monitoring Programme 2022–2027

The main purpose of the programme is to provide a coherent and comprehensive national overview of the ecological and chemical status of surface waters (rivers, lakes, transitional and coastal waters) and the quantitative and chemical status of groundwaters.

FAQs about freshwater & marine

in: Freshwater and Marine

The EPA works with others to monitor and assess the health of our rivers, lakes, estuaries and coastal waters under the Water Framework Directive.

FAQs on freshwater & marine

Learn more about water quality in Ireland - watch talks from the 2024 EPA Water Conference