John Terence Curtis, of Roanhead Farm at Dalton-in-Furness, pleaded guilty to causing polluting matter to enter a tributary of the Duddon Estuary, which in turn flowed onto the beach at Sandscale.

Jane Morgan, prosecuting for the Environment Agency, told the court that following a report from a member of the public, an Environment Officer discovered a black smelly discharge flowing from a stream onto the beach.

The bed of the stream and the vegetation in it were black and a scummy layer was present on the surface. The bed was also covered in a grey fungus, the water smelt like slurry and the sand on the beach was black.

The officer traced the pollution upstream 500m to Roanhead Farm. Mr Curtis told the Agency that he had spread the farmland two to three weeks previously with slurry, silage liquor and parlour washing from the farm’s slurry tank. He believed this had entered a land drain connecting to the stream.

Mr Curtis had previously been investigated for offences of causing polluting matter to enter controlled waters and has received warning letters from the Agency. In January 1999 he received a warning letter following a fish mortality which occurred following slurry spreading to land. In November 2001 he received a further warning letter in connection with another pollution incident.

Environment Officer Jon Turner said: "Discharges can cause serious damage to our streams and rivers and so good management of farm effluents is essential. We advise any farmers who spread muck to create a buffer strip to avoid runoff and to avoid spreading it when conditions are particularly wet."