Research has identified a Chingford road as one of the highest contributors to river pollution and poor water quality in London

Pollution from the surface of the North Circular in Chingford is posing a significant risk to rivers, a study has found

Research funded by City Hall, Transport for London and the Environment Agency, found the road is one of the worst in London for polluting rivers.

The data shows roads where heavy goods vehicles (HGVs) regularly apply their brakes are often the worst affected, usually around junctions, roundabouts and traffic lights.

This is the first time that dedicated research has been carried out to identify sources of this specific type of pollution, known as road run-off.

Mayor of London, Sadiq Khan said: “We’re working with partners to find solutions that prevent water contamination, but the government must step up to provide the Environment Agency and highways authorities with the appropriate funding for these measures to properly protect the capital’s rivers.”

Road run-off occurs when pollutants that settle on the surface of the road - such as residue from oil spills, as well as tyre and brake wear from vehicles - build up during dry weather and are then washed into rivers and streams when it rains.

Toxic metals, hydrocarbons found in fuel and other pollutants washed into water pose a significant threat to river health.

Road run-off can carry over 300 pollutants, killing fish and even discolouring water turning the river water black.

Rob Shore, Head of UK Programmes at wetland charity WWT, said: “It is clear that road runoff is a major source of river pollution across the UK, especially in our urban areas, killing aquatic wildlife and making our towns and cities less hospitable for people.

“We welcome the report’s investigation into this important issue, and strongly support the report’s recognition of wetlands and sustainable drainage systems as a key part of the solution. Creating new urban wetlands will capture run-off before it gets into our rivers whilst providing a range of other benefits such as flood alleviation, wildlife habitat and improvements to air quality”.