THOUSANDS of fish have died after suffocating in a frozen lake.
The fish are thought to have been starved of oxygen after ice up to 18 inches thick formed at Mount Pleasant Lake, Fatfield, Washington, during the extreme cold spell over Christmas and New Year.
The Washington and Harraton Angling Club, which leases the site from Sunderland City Council, only recently made the shocking discovery after the slow thaw.
Dead carp, roach and eels have been spotted under the ice.
Wheatley Smith, club chairman, said: “It looks as if there are thousands of dead fish down there. It’s not just the smaller ones. There are some that weigh between six to 10 pounds.
“Nobody realised how thick the ice was. It’s only been in the past week or so that we’ve been able to see through it.
“We now think it was up to 18 inches at one point.”
Mr Smith, who lives nearby and has looked after the lake for more than 30 years, said he had never witnessed such a scene at the site.
“There was no way to break through the ice,” said the 63-year-old. “I tried using a hammer to smash through it when I found out what had happened, but it was no good. Even at the edges it was too thick.
“I’ve never known anything like it. We’ve had freezes in the past, but nothing as bad as this.
“There was also a public safety issue in that had we broken up the ice, then someone might have fallen through it if they’d tried to walk across it.”
Once the club has carried out the grim job of removing the dead fish, the lake is expected to be re-stocked in the coming months.
Club secretary Dave Hancock, 62, from Shiney Row, said: “We’ve lost a lot of fish. God knows how much it will cost to re-stock the lake.”
The Environment Agency today confirmed it had been alerted to the incident and was investigating.
A spokeswoman said it was likely the fish had died because of a lack of oxygen.
“Rotting vegetation and dead fish would also strip oxygen from the water, which makes it more difficult for anything to survive in the winter,” she added.