Thames Water is to pay almost £100,000 after allowing sewage to escape from a blocked sewer in south-east London.

The utility will pay £80,000 to the South East Rivers Trust to make improvements to a local river and pay the Environment Agency's full costs for the investigation of almost £20k.

The incident occurred in 2013 when 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.


It is believed the sewage killed 20 stickleback fish and hundreds of invertebrates.

Jamie Lloyd, a land and water officer for the Environment Agency in south-east London, said: "A lack of maintenance by Thames Water over an extended period of time was to blame for this incident.

"Tree roots were allowed to grow into the sewer unchecked, resulting in fat and sewage solids causing a complete blockage. Sewage backed-up and was sent with some force through two manholes, triggering significant pollution. Thames Water compounded the pollution by failing to clear the sewer quickly after the Environment Agency reported the incident to them."

Thames Water has since installed equipment to monitor sewage levels in its sewer network, near to where the blockage occurred. The company has also relined the sewer to help prevent roots entering the pipes again.

The South East Rivers Trust, which helps communities look after rivers, will use the money to install a fish pass on the River Cray at Bexley, allowing various types of fish to swim upstream.

(CM/MH)