Aquatic research informs policies and practices to reduce pollution from road run-off



Having the tools to identify where additional mitigation measures are needed, which both the environmental regulators and the highways authorities trust, is immensely valuable. For example, it will ensure that protection of the water environment is properly taken into account in developing the UK government's programme for roads in England.

Phil Chatfield, Environment Agency

Water pollution in England and Wales costs around £1.3 billion a year, to which road run-off is a major contributor. Many pollutants such as toxic heavy metals are washed off roads and into surrounding waterways, poisoning aquatic wildlife. A series of studies have investigated how and to what extent this road run-off impacts aquatic ecosystems.

From the basis of an initial study on stream ecosystems along the M1 commissioned and funded by oil company Castrol, more site-specific studies have been conducted by Professor Lorraine Maltby and her team for the Highways Agency and Environment Agency. These studies demonstrated that deposits of pollution washed off roads cause the most serious ecological impacts in aquatic environments.

This has highlighted the need for monitoring and control of this major source of water pollution, and has guided the Highways Agency, responsible for the UK’s 4300 miles of roads, in working to reduce the environmental impact of road run-off. Cost-effective management solutions have been developed, which take into account how the properties of different waterways influence the impact of the pollution.

New policies and practices to mitigate the impact of road run-off are in place, and influential documents and assessment tools are being utilised internationally to determine the ecological risk and appropriate action.