Flood risk and drainage impact additional guidance

This summary explains how we manage flood risk and drainage in new developments. It supports national planning policy and helps developers design safe and sustainable sites. The latest detailed guidance document is available to download.

Who this guidance is for

  • Developers and agents
  • Architects and engineers
  • Landowners and householders
  • Planning officers and consultees

Why flood risk matters

Flooding can damage property, disrupt communities and harm the environment. Our aims are to:

  • Prevent building in areas at risk of flooding
  • Reduce flood risk to existing developments
  • Ensure drainage systems are sustainable and well-maintained

Key principles

The core principles are:

  • Consider flood risk early in the planning process
  • Use sustainable drainage systems (SuDS)
  • Avoid increasing flood risk elsewhere
  • Maintain access to watercourses
  • Allow space for natural water movement
  • Work with the water environment, not against it

Download the latest in-depth guidance

Page last modified: 16 September 2025