Hundreds of trout have died in a pollution incident on the Pill River in West Somerset.

A mystery pollutant has wiped out the entire fish population on a four mile stretch of river between the village of Withycombe and Blue Anchor near Minehead. Environment Agency officers have been on site recovering dead fish and taking water samples. It is thought the fish were killed by a chemical – possibly a pesticide or sheep dip.

The first dead trout were found on Sunday afternoon at a holiday park in Blue Anchor. Agency officers discovered hundreds of casualties as they began their investigation. Samples have been send to the Agency’s laboratory at Starcross near Exeter for analysis. Officers are working their way up the catchment and concentrating their efforts on the area upstream of Withycombe on the Brendon Hills.

Most of the casualties were between 6 – 8 inches in length and included bullheads as well as trout. Close inspection of the fish suggests they have been dead for 2 – 3 days.

‘Judging from the number of fish killed, we believe it was some kind of toxic chemical. It must have been pretty nasty because it also wiped out a lot of the invertebrate life in the stream. In all likelihood, it was probably a pesticide or sheep dip,’ said Jim Grundy for the Environment Agency, who confirmed that as part of their investigation, officers would be visiting local farms.