By Sarah Clarke and James McNaney
Over the last decade there has been an average of more than one pollution incident every day in Lough Neagh and its tributary rivers, UTV can reveal.
Almost 4,000 pollution incidents were reported by the Department of Agriculture and Rural Affairs over the last decade.
UTV's Up Close: What Lies Beneath has uncovered the extent of the ecological crisis facing Northern Ireland's largest body of water and the UK's largest freshwater lake.
Figures revealed in a Freedom of Information Act show the extent of pollution into the lough and the rivers that feed into it between 2012-2022.
There were 3,837 pollution incidents reported by the department in this time frame, which averages out to more than one per day.
These incidents lead to 44 fish kills, of which 24 were classed as major.
The health of Lough Neagh became the subject of widespread public debate in Northern Ireland over the summer of 2023, after several algae blooms threatened livelihoods and wildlife.
Mark Tierney of the Ulster Angling Federation says he has witnessed a pollution incident and reported it to the environment agency.
"They came out, in reasonably good time, investigated, contacted me back to say it wasn't excessive discharge.
"Now the water was pure orange. So my argument is, if it wasn't in excess of discharge consents, why are the discharge consents allowed to be that high?
"Because it was obvious to anyone that the river wasn't fit for habitation for juvenile fish or entomology.
"There's pollution incidents that wipe out fly life: fly life is every bit as important as the fish.
"The flies are the blood, the bare bones of what we need for our fish, that's their main diet."
Up Close: What Lies Beneath airs on UTV on Thursday 16 November at 10.45pm. The programme was produced and directed by Brendan Mc Court and is presented by UTV reporter Sarah Clarke. It will be available online here.
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