Flooding can cause widespread economic and social damage, so the control of flood risk is often vital to a project’s long-term success. On brown and green field sites that are initially identified by a Flood Risk Assessment as being at risk of flooding, mitigation measures need to be incorporated into the design to allow for extreme climatic events such as severe storms, prolonged rainfall or tidal surges.

Using detailed hydrological modelling, our water engineering team assesses the feasibility and type of flood mitigation required to meet a client’s aspirations for the site, following this with a detailed design specification. Thanks to our methodical – and environmentally sensitive – approach to the management of flood risk, many ‘problem’ sites are able to obtain planning consent and realise their development potential.
 
There are a variety of mitigation techniques available depending on the nature of the risk. The introduction of protective structures can affect the physical balance, so careful parameters have to be set for their design. Flood defence measures can include river and coastal erosion protection schemes, river flow attenuation, strengthening of waterfront walls and banks, in-channel gates and weirs and flood-resilient building design.
 
Sustainable flood protection should tackle the legacy of previous development in areas of high flood risk in a variety of ways, not always involving an engineered solution. ‘Hard’ defences such as river walls may not always be a suitable long-term solution – flooding is a natural occurrence that is sometimes better contained and managed using ‘soft’ techniques, for example by enhancing existing flood meadows and salt marshes.

Buro Happold has extensive experience in the management of water issues in a range of challenging environments around the world. Our projects have ranged from waterside and coastal developments to complex urban regeneration schemes sited on flood plains. Working closely with bodies such as the Environment Agency, our in-depth assessments and sustainable designs help clients make the most of the many commercial opportunities that waterside and redevelopment sites present.