When you're looking to build or extend, especially in areas that might be prone to flooding, there's a crucial step many people aren't fully aware of: the flood risk assessment. It sounds a bit daunting, doesn't it? But think of it less as a bureaucratic hurdle and more as a sensible conversation about protecting your future project and the surrounding community.
Essentially, the Environment Agency in England has laid out guidance to help planning applicants understand and address potential flood risks. This isn't about scaring you, but about ensuring that development happens in the safest possible places. They've categorized areas into Flood Zones 1, 2, 3, and 3b, each with varying levels of flood risk. You can usually find this information through a 'flood map for planning'.
One of the key concepts you'll encounter is the 'sequential test'. The idea here is straightforward: steer development towards areas with the lowest flood risk first. It's like choosing the safest route when you're driving somewhere new. If there are lower-risk sites available, your proposed development might be steered towards those instead. This test is particularly important for larger developments or those with vulnerable elements, and it applies if your site falls into Flood Zone 2 or 3, or even certain parts of Flood Zone 1 if local data suggests a future risk.
However, not every project needs to go through this rigorous process. For instance, simple householder developments like extensions, conservatories, or loft conversions are generally exempt. Small non-domestic extensions (under 250 square metres) and most changes of use also fall outside the sequential test requirement. There are also specific exemptions for developments solely at risk from surface water flooding, provided a site-specific assessment confirms it will be safe.
If your development does require a sequential test, the advice is to engage with your Local Planning Authority (LPA) early on. They can help you define the 'area of search' for alternative sites and guide you on what information to include with your application. You might even need to identify other 'reasonably available' sites yourself, perhaps those currently on the open market.
Should your development pass the sequential test, you might then need to consider the 'exception test'. This is a further layer of scrutiny, particularly for developments classified as 'highly vulnerable' in Flood Zone 2, or 'more vulnerable' and 'essential infrastructure' in Flood Zone 3a or 3b. The exception test has two parts, ensuring that the development provides wider sustainability benefits and is also safe from flooding throughout its lifetime.
Beyond these tests, the guidance also touches on what to include in your flood risk assessment, whether you need a Sustainable Drainage Systems (SuDS) strategy, and how to get planning advice. It's all part of a comprehensive approach to ensure that new developments are resilient and safe, considering not just current risks but also those that might emerge in the future due to climate change. It’s about building with foresight, ensuring peace of mind for everyone involved.
