As architects, we spend a sizeable amount of our time dealing with planning applications but what challenges do we face with our designs? We are going to take a look at some of the most common challenges we face over a series of blogs and in today’s blog, we specifically look at the impact of flood zones.
As part of our initial RIBA Stage 0-2 of the architectural process (client brief to concept design), we carry out a number of checks which include determining which flood zone a proposed project falls within. Flood zone 1 indicates an area that is least likely to flood (with 0.1% chance of flooding), flood zone 2 indicates an area with a low risk of flooding (0.1%-1% from rivers and 0.1%-0.5% from the sea) and flood zone 3 indicates an area which is more likely to flood (1% or greater risk from rivers and 0.5% or greater risk from the sea).
Flood zone 3 is split into two separate categories, Flood Zone 3A and Flood Zone 3B. Properties located within flood zone 3 are required to submit a flood risk assessment as part of any planning applications to determine if the site falls under either flood zone 3a or 3b. We work in partnership with civil engineers who then produce a flood risk assessment which also reviews the flood risk to the specific location itself and proposes any possible mitigation. If a project falls within flood zone 3b planning would not be permitted as it would be classed as a more vulnerable development within the functional flood plain. Evidence is therefore required in the flood risk assessment to confirm how a site has been established as sitting with flood zone 3a.
We would always advise that you seek advice from a civil engineer if your site is located within a flood zone to determine which zone applies and the viability of your project within a flood area.