A Otago dairy company that let cow effluent leak into the Pomahaka River last year will have to pay $39,000 in fines.
Balclutha dairy company Greg Cowley Limited had pleaded guilty to discharging dairy farm effluent onto land in circumstances where it might enter water.
The charge was brought by the Otago Regional Council after an inspection of the farm last April.
A failure with an irrigation machine had caused effluent to spread over most of a large paddock.
The discharge was identified as being 'moderately serious', meaning it was an unintentional, but careless.
The Otago Regional Council says the prosecution is a good result for the environment.