Flood Risk Assessments if You’re Applying for Planning Permission

Do I need a Flood Risk Assessment as Part of my Planning Application?

This question is frequently asked by clients who are developing land or extending an existing property.

If you are developing land either for commercial, residential, or an extension to an existing property, you need to have a clear understanding of the impact your development will have. As part of the planning application process, you will need to complete all the necessary risk assessments to make sure your planning application has the best possible chance of being approved.

A flood risk assessment is required when making a planning application for a development that is located in the floodplain or in an area affected by flooding.  If you don’t include a flood risk assessment or your flood risk assessment is not satisfactory, then your planning application may be refused by your local planning authority.

What is a Flood Risk Assessment (FRA)?

As a planning applicant, you may need to carry out a flood risk assessment for your proposed development site. But you may be unsure why you need a FRA as your development site is not near a river or at immediate risk of flooding.

It is becoming increasingly important to get advice from a flood risk consultant in the early stages of the planning process. By understanding the flood risks of your development site at an early stage in the planning process you may save yourself a lot of time and money. Without a FRA you may not get your planning permission and your project could be delayed or worse still require new plans and designs for planning permission to be granted.

A Flood Risk Assessment, also known as a FRA, is a report that details the main flood risks to a development site. The FRA is frequently needed as part of the planning application for development. Your local planning authority may be refused your planning application if you don’t include a FRA or isn’t detailed and completed correctly.

So it is essential to identify if your development site lies in a flood risk zone early in your planning application preparation.

Find out more about Flood Risk Assessments (FRA)

Take a look at some of the questions we are frequently asked

When do you need a Flood Risk Assessment?

Ideally, a FRA should be completed as part of your pre-planning process, so that architectural designs for the development can include any design changes to your scheme.

If your development site is greater than 1 hectare or in a sensitive location, you must submit a Flood Risk Assessment as part of your planning process.

But how do you know where the flood zones are and what you need to submit? At Earth Environmental we can support your planning process and give you quality advice.

The scope and details of the Flood Risk Assessments will vary depending on the size and topography of the site, and which Flood Zone the site lies within.

You need to undertake a flood risk assessment for most developments within one of the flood zones.

This includes developments:

• in Flood Zone 2 or 3 including minor development and change of use
• more than 1 hectare (ha) in Flood Zone 1
• less than 1 ha in Flood Zone 1, including a change of use in development type to a more vulnerable class (for example from commercial to residential), where they could be affected by sources of flooding other than rivers and the sea (for example surface water drains, reservoirs)
• in an area within Flood Zone 1 which has critical drainage problems as notified by the Environment Agency

When you don’t need an assessment?

You don’t need to undertake a flood risk assessment for a development that’s less than 1 ha in Flood Zone 1, unless it could be affected by sources of flooding other than rivers and the sea, for example surface water drains.

It is important to note that surface water drainage can have an important impact on your development’s flood risk and it is prudent to discuss this early in the planning process.  A surface water drainage strategy is a report detailing how surface water can affect a site and surrounding areas. It establishes how water can behave on a site, and estimates the surface runoff rate, viable flow pathways and likely sub-surface infiltration.

What about minor developments do they need a Flood Risk Assessment?

Minor developments are unlikely to raise significant flood risk issues unless:

• they would have an adverse effect on a watercourse, floodplain or its flood defences;
• they would impede access to flood defence and management facilities, or;
• where the cumulative impact of such developments would have a significant effect on local flood storage capacity or flood flows.

Flood Risk Mitigation

Earth Environmental & Geotechnical can also provide independent, professional advice to insurance companies, property owners, the construction industry, architects, and property developers who wish to mitigate and reduce the impact of flooding. Flood risk mitigation focuses on decreasing the consequences of floods through measures inside the vulnerable area. Flooding in the UK is increasing in frequency and having a greater impact. We can help you understand the source of the flooding and the pathway. We can then advise on mitigation design and steps to take to reduce the impact of the flooding.

Who provides Flood Risk Assessments?

You will usually need a flood risk specialist like Earth Environmental & Geotechnical to complete the flood risk assessment for you. You may consider doing it yourself if it’s for a simple, low-risk development, for example, a house extension in a non flood risk area. But you also need to consider the surface water drainage issues and check if your development site is in an area identified as having critical drainage problems.

Earth Environmental & Geotechnical can provide all the services required to ensure your planning application, whatever the development needs, is supported by the correct risk assessments and documents that you will require at the early stages of the planning process.

Earth Environmental & Geotechnical ensure our Flood risk Reports adhere to the current national planning policy (NPPF (PPS25), SPP, TAN 15, PPS-15) 

Earth Environmental & Geotechnical has extensive experience in supporting planning applications and geotechnical services for a wide range of sectors including, residential housing, commercial, recreational, utilities, local authorities, and infrastructure.

Contact us to discuss your development and if you need a Flood Risk Assessment