You need to consider flood risk 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 the risk of flooding elsewhere.

Types of flood risk area

There are three types of flood risk area:

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

New development should be steered towards flood zone 1. If there are no reasonably available sites in flood zone 1, the determining of planning applications 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. This should take into account the flood risk vulnerability of land uses, applying the exception test if required.

For more details about flood risk areas and flood risk in general, see 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 assessments

You need to submit a flood risk assessment with your planning application if it's for:

• a development 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.