A report launched by Stormwater Shepherds and CIWEM shines a light on the toxic cocktail of pollutants that runs off the UK’s road network and into our rivers and water sources every time it rains.

The pollution comes from tyre particles, fuel spills and other vehicle fluids, road surface fragments, sediment and herbicides. These contain heavy metals and toxic chemicals such as polyaromatic hydrocarbons (PAHs) which have shown to be carcinogenic and hormone disrupting to aquatic life.

There are likely 100s of thousands, if not millions, of highway outfalls across the country discharging this toxic mix into the water environment. Yet these outfalls are unmonitored and largely uncontrolled, despite the control of pollution from National Highways’ road network being a statutory duty.

The lack of routine monitoring of these outfalls by the Environment Agency, National Highways and local highway authorities means that their impact on aquatic ecosystems and human health is not well understood.

With sewage dominating political and media attention this pollution has been flying under the radar.

Other polluting discharges to water must be controlled under the Environmental Permitting Regulations subject to a sequence of tests being met. Yet highway outfalls are not permitted, due to a voluntary agreement between the Environment Agency and National Highways.