Toxic pollution that has killed around 50,000 fish along a Wolverhampton canal has spread more than 30 miles, anglers said today.
Pollution which started from a Severn Trent sewage plant in waterways on the Pendeford-Oxley border is now being detected in Market Drayton, although it is no longer strong enough to kill any fish after being diluted by environment bosses.
News of the pollution comes after anglers finished compiling a dossier of evidence about the chemical spillage along the Shropshire Union and Staffordshire & Worcestershire canals.
They will be handing the dossier over to Fish Legal, which fights against water pollution across the country. It could lead to legal action being taken against Severn Trent Water, which has already confirmed the source of the problem was its Barnhurst sewage plant near Autherley Junction in Wolverhampton, where ammonia is reported to have been discharged into the canal network after leaking into the treatment works.
The contamination began on April 18 and since then thousands of dead fish such as pike and bream have been removed from the canals. British Waterways has been pumping clean water into contaminated stretches of canal from the Belvide Reservoir at Penkridge in a bid to dilute the pollution.
Alan Gough, of Wolverhampton Angling Association, said today: "The Environment Agency is still monitoring the pollution levels and where it has travelled. Some is being detected as far away as Market Drayton although it is no longer strong enough to kill any of the fish.
"We have completed a dossier of evidence about the events since the contamination which we will be presenting to Fish Legal at the weekend."
The pollution came just days after the canal network was re-stocked with around 6,000 fish to entice more anglers.
The canals are soon set to become a hive of activity as the host of the First Division National angling competion, which Mr Gough described as the "Premier League" of the fishing world. More than 400 anglers are set to descend on a stretch of the Staffs & Worcester Canal through Wolverhampton, Penkridge and Stafford for the contest on August 8.
Mr Gough said it had been feared that the competition would be under threat following the far-reaching pollution. But he insisted the competition would definitely still be going ahead as planned because the contamination had been successfully diluted.
"As well as the initial pollution, these sorts have things have consequences that last," said Mr Gough.
"People were getting worried that the pollution had decimated the fish pollution further down the canal but it is not the case and the competition will still go ahead as planned."