Flooding and flood risk

Brent has two main rivers, the River Brent and the Wealdstone Brook. The areas next to these rivers form part of a natural flood plain.

Out of the estimated 118,500 properties in Brent, approximately 1,390 are potentially at risk of river flooding at least once every 100 years, and 2,000 properties are at risk of flooding once every 1,000 years.

Brent is also susceptible to flooding from different sources such as high intensity rainfall. The areas of flood risk tend to be located within the highway.

Brent has 27 critical drainage areas. Instances of sewer flooding are generally higher in the north of the borough than in the south.

Am I in a flood risk area?

To find out which fluvial flood zone your property is in, visit the Flood Risk Assessment map on the GOV.UK website and search using a place name or a postcode.

What is a Flood Risk Assessment?

Certain planning applications must be accompanied by a Flood Risk Assessment (FRA).

The FRA ensures the land or property is suitable for the proposed development. It shows how flooding to and from the development will be managed and mitigated, both now and in the future, taking the impacts of climate change into account.

If your application requires a FRA, you may need to contact a consultant to prepare it for you.

Do I need a Flood Risk Assessment?

You will need a FRA for development proposals:

• more than one hectare (ha) in flood zone 1
• of any size including change of use within flood zones 2 or 3
• less than 1 ha in flood zone 1 including change of use in development type to a more vulnerable class where they could be affected by sources of flooding other than rivers
• in an area with critical drainage problems 

The GOV.UK website has further guidance on when a FRA is needed. Further details on sources of flood risk, including surface water flood zone 3 which covers extensive areas in Brent and FRAs, can be found on the West London Strategic Flood Risk Assessment website.

If your application requires a FRA, and you do not submit one, your application will not be validated.

How is the Environment Agency involved?

We consult the Environment Agency (EA) on certain applications within fluvial flood zones 2 and 3, as well as any application over one hectare in flood zone 1, and smaller applications in flood zone 1 which are in areas that have critical drainage issues.

Should your application be referable to the EA, we will issue the consultation.

View the EA's information on the flooding implications of different applications

View the EA’s information on how to prepare for a flood and the EA flood line number

Other flood risk studies and strategies for Brent

• Strategic Flood Risk Assessment Level 2 (2020)
• Strategic Flood Risk Assessment Level 2 Appendix B (site assessments) (2020)
• Flood Risk Sequential and Exceptions Test update
• Surface Water Management Plan (.pdf, 3.14MB)
• Surface water management plan appendices (.pdf, 5.33MB)
• Flood risk management strategy. (.pdf, 1.72MB)