Monthly Hydrology Bulletin

The EPA publishes a monthly Hydrology Bulletin which provides a factual summary of river flows, lake levels and groundwater levels for the previous month and also includes a comparison to historic monthly values. 

The EPA runs a national hydrometric monitoring programme which measures the flow in rivers, lake levels and groundwater levels at a network of over 350 stations across Ireland.  The data is used for environmental assessment, research, and regulatory purposes.

The bulletin contains river flow and water level graphs for a sample of surface water and groundwater hydrometric stations across Ireland. The bulletin also contains maps which show how flows and levels at stations across the country compare to the average for the month.

Learn more:

Download the latest Monthly Hydrology Bulletin:–assessment/freshwater–marine/hydrology-bulletin/

Further details of the hydrometric stations and data downloads can be obtained from and

About the National Hydrometric Programme

In this video we follow the Hydrometric and Groundwater Unit in their mission to measure and monitor Ireland’s water levels and flows.

The Hydrometric Programme is a national programme for the collection, analysis and distribution of data on water quantity. The EPA is required to prepare this programme by the Environmental Protection Agency Act (1992).

Hydrometric data gathered by this programme include flows and water levels of rivers and canals, lake water levels, groundwater levels (and flow from springs) and water levels in the sea.

The Hydrometric Programme is carried out with co-operation between:

Working together with the organisations above ensures an efficient service to the various local authorities, government agencies, consultants, private industry and the public.

The EPA reviews the Hydrometric Programme and the hydrometric network every five years. You can download the National Hydrometric Monitoring Programme 2022-2027.

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.