lady with umbrella walking down flooded street

Fully compliant Flood Risk Assessments (FRA) for planning

A Flood Risk Assessment (FRA) is typically required as part of the planning process for new development or where alterations to existing buildings or infrastructure in areas at risk of flooding. The need for an FRA is determined by the Environment Agency, local planning authorities, or the relevant regulatory bodies. An FRA is typically necessary in the following circumstances:

  • Development in the Flood Zone: If your proposed development is located in a flood risk area designated as Flood Zone 2 or 3, you will need to provide an FRA.
  • Development Size: The size and scale of the development can trigger the requirement for an FRA. Large developments, such as housing estates or industrial complexes, are more likely to require an assessment.
  • Proximity to Watercourses: Developments located near rivers, lakes, or the coast are more likely to be subject to flood risk assessments due to the increased potential for flooding.
  • Change of Land Use: If your project involves a change of land use, such as converting agricultural land into residential or commercial use, it may trigger the need for an FRA.
  • Local Planning Policy: Local planning authorities may have specific policies or guidelines regarding Flood Risk Assessments that could apply to your development.
  • Infrastructure Projects: Major infrastructure projects, like roads, bridges, or railways, which could impact flood risk in the area may require an FRA.




 Is a Flood Risk Assessment necessary on your project?

Consult with one of Flume's flood risk consultants to determine whether a Flood Risk Assessment is necessary for their specific development or project. Our flood risk consultants are here to guide you through the process and provide the necessary assessments and expertise to help you make informed decisions about flood risk management for your project.

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Our approach to Flood Risk Assessment

Our flood risk consultants have extensive experience working with the Environment Agency to ensure a smooth approval process. At Flume, our commitment is to deliver compliant, efficient, and affordable solutions for our clients. Our pragmatic approach to engineering solutions ultimately improves your chances of obtaining planning consent, avoiding costly design changes and additional planning applications.



 A full breakdown of our flood risk management services includes:




Frequently asked questions

Do I need a Flood Risk Assessment?

Since the implementation of new regulations in April 2015, an increasing number of planning applicants have found it necessary to conduct a Flood Risk Assessment (FRA) when undertaking property development and construction projects. To ensure a comprehensive assessment covering all critical aspects, it is advisable to engage a flood risk specialist or engineer to perform the assessment. Failing to complete a flood risk assessment before submitting your planning application can result in an application being refused. Furthermore, if your property site is situated in a Flood Zone, an FRA is typically mandatory, even for minor developments like householder extensions.

How are flood zones (in England) classified?

There are four classifications for flood zones;

Zone 1 areas have a low probability of flooding. More specifically, they have a 1 in 1000 chance of flooding annually. Land within Flood Zone 1 is categorised as not being within the floodplain, and outside Flood Zones Two and Three.

Zone 2 areas have a medium probability of flooding; that is between a 1 in 100 and 1 in 1000 chance of river flooding annually, or a 1 in 200 to 1 in 1000 annual probability of sea flooding.

Zone 3a areas have a high probability of flooding; that is a 1 in 100 chance of river flooding or a 1 in 200 chance of sea flooding.

Zone 3b areas are within the ‘functional floodplain’. This is where flood water is stored in the event of sea and river flooding. These areas are typically noted as having a 1 in 20 annual probability of flooding.

Do I need a Flood Risk Assessment?

In Flood Zones 2 or 3, a Flood Risk Assessment is mandatory for all properties. Properties in Zone 1, with a low probability of flooding, typically do not require a mandatory Flood Risk Assessment. However, it's important to note that property developers working in Flood Zone 1 may still need to address flood risk concerns if the site resides in a Critical Drainage Area (CDA), as defined by the Environment Agency or Local Authority.

For Zones 2 and 3, even minor developments and changes in property or land use require a Flood Risk Assessment. For instance, if a developer intends to convert a commercial building into a residential dwelling, they must assess how this change will impact flood risk to both site users and how this might impact third-party flood risk.

Contact one of our flood risk consultants to explore how our flood risk team can meet your specific needs and project goals.



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