Understanding and assessing flood risk
Check if a flood risk assessment is needed
A flood risk assessment (FRA) is required for all development (including change of use):
- within flood zones 2, 3 or 3b
- within flood zone 1 with a site area of 1 hectare or more
- within areas with critical drainage problems
- within flood zone 1 where your LPA's SFRA shows it will be at risk of flooding from rivers or the sea in future
- that increases the vulnerability classification1 and is in flood zone 1 where your LPA's SFRA shows it is at risk from other sources of flooding
If a FRA is required, the LPA can refuse planning permission if you don’t provide one, or if the FRA you provide is inadequate.
- https://www.gov.uk/guidance/national-planning-policy-framework/annex-3-flood-risk-vulnerability-classification