A new 23-home housing development, where we have been providing Civil and Structural Engineering support, is nearing completion. Manor Green, located in the South Norfolk village of Hales, has been hailed a Sustainable Drainage (SuDS) success. The SuDS has been designed and approved through the Section 38 process to the satisfaction of Norfolk County Council Highways and LLFA Departments.

What are SuDS?
SuDS are a solution within construction to allow natural drainage and encourage infiltration of surface water to help prevent flooding and pollution risks that can arise from urban run-off.

Often swales and filter strips are incorporated in SuDS design which can be covered by grass or other natural coverings such as wildflowers to allow for an eco-friendly solution. The filter strips remove silt found within the water before it reaches the swale to prevent it from clogging up. Swales are shallow channels that allow for water to be collected before it filters through to the ground underneath.

SuDS at Manor Green
At Manor Green, we opted for filter strips and swales covered by grass along the edge of the paving to enable water on the highways to be naturally filtered away. The surface water, once captured within these swales, then either absorbs naturally into the surrounding ground or down into a perforated pipe. The pipe then directs the remaining water into two soakaways within the housing development.

The Future of Sustainable Drainage
SuDS is a sustainable drainage solution which moves away from the traditional approach, that would generally have surface water run-off going through underground pipes and into large storage tanks.

SuDS offers significant advantages over conventional pipe drainage systems. Flood risk is reduced by attenuating the rate and quantity of surface water run-off from a site, which therefore promotes groundwater recharge and improves water quality and amenity.

Planning Policy requires all future housing developments to incorporate SuDS within their plans to help tackle the effects of climate change and to protect our environment.