SuDS Surface Water Drainage Strategy & Flood Risk Assessment
Civilistix Consulting Engineers were appointed to prepare a detailed Drainage Strategy and Flood Risk Assessment as well as a Civil Engineering Site Appraisal to support a planning application for a 200-bed hotel and multi-storey car park at the existing Birmingham NEC site.
We innovatively integrated SuDS drainage features into the highly urbanised site masterplan proposals without compromising the level of urbanisation the developer wished to achieve whilst simultaneously keeping all stakeholders happy including the Lead Local Flood Authority, ensuring planning was passed first time round.
Our SuDS design included permeable paving to all hardstanding areas, a large central dry swale which highway gullies directly discharged into, and geo-cellular storage to accommodate the residual attenuation volume required.
Due to the proposed hotel and multi-storey car park footprints being located on top of existing 1200mm and 450mm surface and foul water sewers respectively, for development to be deliverable it had to be demonstrated how diversions could satisfactorily occur. To this end, we prepared detailed diversion plans and hydraulic models to demonstrate how flow velocity, flow capacity and cover and bedding to sewers within the diverted state would not be compromised from the levels achieved from the existing scenario.