Beverley Brook mystery solved

On 29 July a major fish kill occurred in Beverley Brook. A large stretch of the brook was impacted including the sections through Richmond Park and Barnes. Between 400 and 500 dead fish were recorded in the affected stretch.

The Environment Agency responded to the incident and have have now produced their report. They concluded that the deaths were caused by the extended period of hot dry weather which was then followed by significant rainfall on the 28 and 29 July.

Prolonged dry weather in urbanised catchments leads to a build-up of contaminants from roads, in addition to organic matter such as leaves, silts and sewage from misconnected properties. All of these materials connect in the surface water drainage system and are released as run-off into rivers during significant rainfall.

The higher temperatures increase the breakdown of organic matter and low flows provide less dilution of the run-off. This can result in a rapid drop-off of oxygen levels which can cause widespread fish mortality. This has been the case in Beverley Brook. 

See the full report plus other local Environment Agency initiatives HERE.