We’re proud to be part of this ambitious project that’s tackling the impact of climate change and population growth. One of the UK’s largest retrofit sustainable urban drainage systems (SuDS), it reduces flood risk for 90,000 people by creating 30 million litres of surface water storage, enhancing amenity spaces for residents and boosting biodiversity for wildlife.
Built
84
interventions with a water storage capacity of 2,031,750 litres
Contract value:
£31 million
"Bringing Kier in as contractors, with the local authorities, Mansfield District Council, Nottinghamshire County Council who contributed so much from a land or approvals point of view – that integrated project team being together really helped us to deliver such a massive project in such a short space of time."
Adam Boucher, Lead on Mansfield Flood Resilience Green Recovery Project, Severn Trent
Sustainable flood resilience
Diverting and slowing down surface water eases the pressure on existing drainage and combined sewer systems reducing flood risk in urban areas where surface water can collect quickly causing drains to overflow. A mosaic of interventions including raingardens, bioswales and detention basins was built across Mansfield to capture and slow surface water flow.
A network of green infrastructure
Appointed to the client’s programme in 2023, the priority was validating the outline design to ensure implementation at scale. Our comprehensive site investigations included determining soil conditions through detailed testing and using Kier’s underground utility clash detection platform QuikSTATS to speed up and inform decision-making. We created topographical surveys and built 3D CAD models. As a result of our approach, fewer interventions had to be built to still capture the required volume of surface water, reducing disruption and delivering best value.
Nature based solutions
As well as providing the vital link between Kier Design, our in-house design function, and other design houses, we built 84 interventions with a total water storage capacity of 2,031,750 litres. The rain gardens have been planted with a careful selection of herbaceous ornamental plants and grasses and the wildlife mix used includes more than 27 species. Our final intervention for the scheme was completed in March 2025.
Residents share their reflections on the impact of this scheme in this short film:
