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Flood risk assessment

Published: 2020-01-27 Updated: 2020-01-27 Subject: Planning, Planning checklist

Planning application - local requirement

When this requirement applies

A Flood Risk Assessment is required if the proposed development falls within a flood zone (as defined by the Environment Agency). Flood zones are classed as 1 to 3 for the purposes of planning decisions, with zone 3 identifying areas with the highest risk of flooding from rivers or the sea. You will need to submit a Flood Risk Assessment with your planning application if your development is one of the following:

In Zones 2 or 3

  • All applications, including minor development and change of use

In Zone 1

  • Developments covering more than a hectare (ha) within the zone
  • Developments where there are additional flooding risks (such as from reservoirs and surface water drains), and the proposal involves building new dwellings, or change of use to residential
  • All applications in an area where there are critical drainage problems (as notified by the Environment Agency)

What the assessment should include

There is detailed advice about what your assessment should include, depending on the type of development you are proposing and the flood zone rating of the site. Follow the flood zone classification and the Environment Agency's Flood Risk Standing Advice below to find the specific information for your application.

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