Readers of Trout in Dirty Places will probably remember that this is the stretch of the Colne which has been hit by an almost unbelievable sequence of pollution incidents in the past few years – most recently the massive fire at the Grosvenor Chemicals works at Linthwaite on 24 May 2010, which needed more than 100 firefighters to bring it under control, and spilt fire foam mixed with a noxious cocktail of chemicals into the Colne and adjacent Huddersfield Canal.
According to this archived report from the Huddersfield Daily Examiner, 4 Improvement Notices covering chemical storage and drainage were issued to Grosvenor Chemicals in 2011, and we’re still awaiting details of any Environment Agency prosecution.
But it’s encouraging that the EA think the river is recovering strongly enough to support a major restocking programme of 0+ grayling genetically sourced from the wider catchment’s stocks:
The young grayling are nearly five months old and have been bred and grown at the Environment Agency’s fish farm at Calverton in Nottinghamshire.
The eggs come from adults caught from West Yorkshire’s River Calder back in March 2012, and the young fish, known as fry, have been grown in a specially designed system that ensures they can thrive in the River Colne.
5,000 grayling were also stocked in June last year, while our EA contacts have assured us that trout will recolonise naturally from the river’s headwaters (so won’t be compromised by introducing farmed-fish strains, in line with the National Trout and Grayling Strategy).
Meanwhile, the great community engagement work of the local Greenstreams project continues. And we live in hope that tighter regulations as a result of the 2010 fire can finally help the Colne to break the curse of its riparian chemical factories, and recover its status as one of the world’s best urban fisheries…