Flood risk and drainage

The effects of climate change, population growth and urbanisation are placing significant pressure on the effective management of surface water. Changing patterns of rainfall and a growing area of impermeable development are giving rise to high rates and volumes of surface water run-off. Conventional drainage systems constructed from constrained networks of underground pipes and storage tanks are struggling to cope with overwhelming quantities of surface water run-off, resulting in problems such as flooding and pollution.

 Planning Policy Statement 25 (PDF 4.7MB) sets out Government policy on development and flood risk. Its aims are to ensure that flood risk is taken into account at all stages in the planning process to avoid inappropriate development in areas at risk of flooding, and to direct development away from areas of highest risk. Where new development is necessary in such areas, policy aims to make it safe, without increasing flood risk elsewhere, and, where possible, reducing flood risk overall. For more information, please click on the links below.