Care urged in managing effluent
Chief environment adviser Sean Regan said the recent wet weather has greatly increased the effluent volume by silage crops.
This year, each tonne of silage could produce up to 30 litres of effluent.
“With up to 20 million tonnes of silage being made nationally over the coming months, we are looking at up to 600 million litres of effluent. This highlights the need for careful management,” he said.
Mr Regan said silage effluent is a vicious pollutant. Unless it is managed carefully it can have devastating effects on fish life and water quality.
Major strides had been made in recent years in reducing the proportion of fish kills caused by farming.
Of the 53 fish kills recorded last year, nine were agriculture-related. This was the lowest proportion in a decade.
“While this is very welcome, continuing vigilance, particularly during silage making, is essential,” he said.
Mr Regan said water levels in rivers and streams are generally low in summer. The warm temperature reduces oxygen levels.
If silage effluent enters a stream or river, it leads to a rapid increase in bacteria and other micro-organisms who use up the available oxygen.
“As fish breath in more water in an attempt to survive, they also take in more of the poison,” he said.
