Environmental specialists working on the Bandon River flood relief project in the West Cork town have said they raised concerns with the company who subcontracted them about the porous nature of a haul road the night before it suddenly drained, leading to stricken fish become trapped.

An environmental health and safety officer for one of the three contracted firms being prosecuted for an alleged fish kill has said staff were incensed by an Inland Fisheries Ireland description of their actions as “panicked”.

A court has heard concerns that major drainage works on the Bandon River could be delayed unless an action brought by Inland Fisheries Ireland against three contractors on the project is resolved.

Three companies working on one of the biggest drainage projects in Europe have appeared in court on charges linked to a fish kill and disturbing spawning beds.