AROUND 1,000 fish have been killed due to contamination in a stream caused by a collapsed sewer.

Members of the public called Bexley Council after noticing hundreds of dead fish in the water leading into Danson Park Lake in Bexleyheath.

Investigations by Thames Water discovered the problem was caused by the collapse of one of its sewers in Welling, resulting in sewage finding its way into the surface water drains which feed into the park.

Steve James, who was walking his dog at the time, said: "I could see some dead fish in the stream which was worrying.

"I'm massively concerned. There's very little, if anything, to say what's happened up there."

The 43-year-old, of Merlin Road North, Welling, added: "Dogs run around by the water. I'm not sure what effect it will have on the animals."

Officers were also brought in from the Environment Agency and have been finding it difficult to assess the scale of the damage due to sewage fungus covering the bed of the water.

Up to 1,000 dead fish, around 10cm in length, were removed and oxygen was added to the water.

Environment Agency area base controller Jonathan Taylor said: “This is a serious incident and our officers have been on site over the weekend placing booms to stop the spread of the pollution.

“The Environment Agency will continue to oversee the clean-up of the incident with Bexley Council and Thames Water. The investigation is ongoing and we have no further details at this stage.”

As a precaution the council has suspended all fishing and water sports in the lake until further notice, following the incident on November 26.

A Thames Water spokeswoman said: "We got to the lake as quickly as possible to reduce the impact, and have been working with the Environment Agency to clean up the stream and pump air back into it.

"Any incident that harms wildlife is deeply regrettable."

To report pollution incidents, call the Environment Agency’s emergency hotline on 0800 807060.