Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, what assessment the Environment Agency has made of the impact of historic highway drainage systems on downstream flooding and water pollution.

Environment Agency (EA) water quality monitoring programmes identify where ‘urban and transport’ inputs are having a potential impact on a waterbody. Water quality monitoring data is publicly available here: Water Data Explorer | Engage Environment Agency. Highways authorities should address outfalls with the potential to pollute.

Water and sewerage companies in England and Wales are currently developing their first statutory Drainage and Wastewater Management Plans (DWMPs), due to be published in 2027/28. These strategic plans identify risks to the companies’ drainage and sewerage networks and set out solutions for how those risks will be mitigated, including environmental risks, which could have implications for highways inputs.

The EA also works with National Highways to assess the impacts of highway drainage on downstream flooding and water quality. They are working together to deliver actions in the National Flood and Coastal Erosion Risk Management (FCERM) Strategy Roadmap. This includes delivering multi-benefit, nature-based solutions that reduce flood risk, improve water quality and enhance biodiversity. The EA supports this through its flood investment programmes, catchment partnerships and use of national flood risk mapping to help target priority locations and future investment.