When do you need a Flood Risk Assessment?
A Flood Risk Assessment (FRA) shows the council that a new building will be safe from flooding and won't make flooding worse for anyone else. Leave it out when it's needed and your application will be held up or refused.
Do you need one?
The quickest way to find out is to look your address up on the Environment Agency's flood map for planning. You'll normally need an FRA if:
- the site is in Flood Zone 2 or 3
- the site is a hectare or more, even in Flood Zone 1
- the council has identified the area as having drainage problems
- you're changing the use to something more vulnerable, like turning a shop into flats
Householder extensions in Flood Zones 2 and 3 usually need one too, but it can be a much shorter document.
What goes in it
It sets out where the flood risk comes from (rivers, sea, surface water, groundwater or sewers), how high the water could get, and what the floor levels of the new building will be. It also covers how the building will cope with water if it does get in, how people would get out safely, and how rainwater from the site will be dealt with.
Think about it early
It's much easier to raise a floor level or change a material at the design stage than after the drawings are done. We prepare FRAs alongside the planning drawings so the two match.
If you're not sure whether your project needs one, ask us.
