There’s no easy way to aggregate all previous Irish Water prosecutions for pollution. Here’s a couple of examples from this week:
Irish Water pleads guilty to polluting habitat of endangered mussel in Co Cork
Ammonia and orthophosphate discharges from firm’s Boherbue plant at multiples of permitted levels
‘Third-world’ water treatment plant dumped five swimming pools of raw sewage into river
Irish Water was fined €7,000 and agreed to pay costs
https://www.irishexaminer.com/news/courtandcrime/arid-40708463.html