Environment Agency: Find out when you need to do a flood risk assessment as part of your planning application, how to do one and how it’s processed.

https://www.gov.uk/guidance/flood-risk-assessment-for-planning-applications

Contents

1. When you need an assessment
2. When you don’t need an assessment
3. When to follow standing advice
4. How to do an assessment
5. Get information to complete an assessment
6. Contact the Environment Agency

As a planning applicant, you may need to carry out a flood risk assessment for your proposed development site. Guidance for local planning authorities can be found in the guide on reviewing flood risk assessments.

You’ll usually need to pay a flood risk specialist to carry out the flood risk assessment for you, but you may be able to do it yourself if it’s for a simple, low risk development, eg a house extension. If you’re unsure, contact the Environment Agency for advice.

Your planning application may be refused by your local planning authority if you don’t include a flood risk assessment or if it isn’t satisfactory.

https://www.gov.uk/guidance/flood-risk-assessment-for-planning-applications