Frankham was commissioned to undertake a full Flood Risk Assessment (FRA) for a mixed-use development including a social club and houses. An FRA is a study of the levels of risk from all potential sources of flooding (plus any historic flood events), which is then measured against National Planning Policy strategy guidelines and acceptable parameters for developments of different types.
Due to proximity to the River Thames, the development was located in a Flood Zone 3a, a higher-risk category The Flood Zone types are as follows: 1 (low probability), 2 (medium probability), 3a (high probability) and 3b (the functional floodplain).
Under the National Planning Policy Framework (NPPF), only certain ‘lower vulnerability’ building uses are permitted in such Flood Zones due to the potential harm a flood could cause. Although the development was located in a Flood Zone 3a, the ground floor use (social club) was a lower vulnerability type than the houses above, and since these floors were above the flood level the development was deemed suitable for the flood zone. The site was also protected by the existing flood defences, including the Thames Barrier.
We provided key design advice on flood mitigation and a full breakdown of flood risk types likely to affect the development. We concluded that the development type was suitable for the flood zone and this was used to support the planning application.