A pollution incident in south-east London has left Thames Water handing over 10s of thousands of pounds to an environmental charity.

After the company allowed sewage to escape from a blocked sewer in 2013, Thames Water will give £80,000 to the South East Rivers Trust to make improvements to a local river. It will also pay the Environment Agency’s full costs for the investigation of almost £20,000.

In October 2013, an underground sewer pipe in Chislehurst became lodged with tree roots, fat, oil, grease and other debris. The build-up forced sewage above ground, flooding a field and two streams, before entering the River Shuttle.

Officers from the Environment Agency believe the sewage, which killed as many as 20 stickleback fish and hundreds of invertebrates, could have been flowing for several days. The effect of the pollution on water quality and river habitats was seen over several miles.