About 90kg (200lbs) of dead fish have been removed from a canal after a sodium cyanide leak in Walsall that experts fear could have “devastated the aquatic ecosystem” in the area.
A 1km stretch of the waterway remains closed to the public after the chemical spill from a metal finishing company, Anochrome. The spill was declared a major incident last week.
Walsall council said testing had shown a 300-metre stretch of the canal was affected by the spill and 90kg of fish carcasses were removed from the canal over the weekend.
“There have been significant numbers of fish killed, but the impact on the wider ecology is not yet known,” the council said.
“Chemical testing will continue on a daily basis, and we are monitoring water levels. Although we hope cyanide levels will fall, we are exploring all potential remediation techniques that may be required in the future.”
Temporary dams have been installed on either side of the affected red zone, where high levels of sodium cyanide and zinc cyanide were recorded.
The Canal & River Trust is trying to raise £10,000 for the cleanup, describing the spill as “extremely distressing” and likely to cause great harm to local wildlife.
The charity’s senior ecologist, Paul Wilkinson, said: “The spillage has been contained to a relatively small area, but the impact on wildlife remains to be seen.
“Sadly, we expect the aquatic ecosystem will have been devastated or lost for the section the pollution has passed through, from the smallest invertebrates right up to the otter that has a territory through that section. Without natural balance, invasives and algae will quickly take over: the impacts could take years to fully recover.”
The charity said “over 100 juvenile fish and dozens of big fish” had been killed, and the number was expected to rise.
The council said the water quality along stretches of the canal, which had been closed in the aftermath of the spill, were within public health guidelines and normal activities could resume. It advised the public not to remove or eat fish from the waterways.
The Environment Agency said it was investigating Anochrome after the spill and described the level of pollution as “unacceptable”.
Symptoms of sodium cyanide poisoning can include nausea, weakness, aches and loss of consciousness. The public has been urged to avoid direct physical contact with canal water along the affected stretch.
