Statement re interagency collaboration - River Blackwater investigation

Wednesday, August 27h, 2025: Inland Fisheries Ireland(IFI), Cork County Council, the EPA, the Marine Institute, and Uisce Éireann are working together to advance the ongoing investigation of fish mortalities on the River Blackwater.

Potential actions to progress the investigation have been discussed, including testing riverbed sediment, analysis of fish mortalities to identify potential harmful substances, and sampling of macroinvertebrates. 

Additional macroinvertebrate sampling will now be executed to try identify where a waterborne irritant may have entered the water.

Cork County Council, the EPA, and IFI will extend this work this week to further assess water and habitat quality overall.

A meeting of all organisations involved was requested by the Minister of State for Fisheries and the Marine, Timmy Dooley TD to enhance State agency collaboration to establish a cause for fish mortalities in the River Blackwater catchment.

IFI, which is coordinating the interagency group, will continue to inspect the affected channel and tributaries for dead or affected fish, and will be liaising closely with all State bodies on the matter.

Agencies are also reviewing historical data to see if any reports received in recent months may be relevant to the incident.

The results of all further testing will be shared once evidence is gathered and analysed.

All five State agencies will continue to meet to respond to the incident.