Development and flood risk

Flood risk is an issue that you need to consider if you're planning any new development or changing the use of an existing development.

One of the main aims of the planning process is to avoid inappropriate development in areas at risk from flooding and to direct development away from areas of highest risk.  Where development is necessary, it's important to make it safe without increasing flood risk elsewhere.

Flood risk areas

There are three different types of flood risk areas:

  • Zone 1 - low probability of flooding
  • Zone 2 - medium probability of flooding
  • Zone 3 - high probability of flooding

The overall aim should be to steer new development to flood zone 1. Where there are no reasonably available sites in flood zone 1, determining planning applications for development at any particular location should take into account the flood risk vulnerability of land uses and consider reasonably available sites in flood zone 2, applying the exception test if required. 

Only where there are no reasonably available sites in flood zones 1 or 2 should the suitability of sites in flood zone 3 be considered, taking into account the flood risk vulnerability of land uses and applying the exception fest if required.  

For more explanation of the different flood risk areas and flood risk in general, check the technical guidance of the National Planning Policy Framework or contact the Environment Agency.

Check if a proposed site falls in a flood risk area

Before submitting a planning application for any type of development, check the Environment Agency's flood risk maps and general flooding information to see if the site falls within a flood risk area.

Flood risk assessment (FRA)

You'll need to submit a flood risk assessment with a planning application where the application's for:

  • a development proposal on a site of one hectare or more in flood zone 1
  • all proposals for new development located in flood zones 2 and 3

If you don't submit a flood risk assessment where one is required, we may invalidate your planning application.