Costco, Norfolk

Flood Prevention

Norfolk’s first Costco entrusts flood risk alleviation to SDS GEOlight®

Overview

Costco’s first warehouse in Norfolk is being developed at Broadland Business Park, Postwick, creating a major new retail destination serving businesses and members across East Anglia. The 5.5-hectare development includes a 13,342m² warehouse, extensive parking, a fuel filling station and EV charging facilities.

SDS was appointed to provide a high-capacity underground attenuation solution to manage significant surface water runoff while satisfying planning requirements and protecting the surrounding area from increased flood risk.

What We Did

SDS supplied three GEOlight® attenuation tanks, providing a combined underground storage volume of more than 2,760m³.

The modular geocellular system provides high-volume storage beneath operational areas, maximising valuable surface space for customer parking and site infrastructure. Its light weight yet structurally robust design also provides the strength required beneath heavily trafficked areas.

The attenuation tanks temporarily store stormwater during peak rainfall events before releasing it at a controlled rate into the wider drainage network. A specialist filter tank was also incorporated within the GEOlight® system to provide treatment to stormwater runoff.

Results

The GEOlight® system forms a key part of the site’s approved surface water management strategy, helping to satisfy planning requirements while managing runoff from the warehouse, extensive hardstanding, parking and fuel filling station.

With more than 2,760m³ of underground attenuation capacity, the solution provides long-term flood risk resilience while making efficient use of the site’s available space.

The project demonstrates the suitability of GEOlight® for large-scale commercial developments where high-capacity attenuation, robust construction and effective surface water management are essential.

SDS provided a robust and efficient underground attenuation solution for the Costco Norwich development. The GEOlight® system delivered the required storage capacity while integrating seamlessly with the wider construction programme, helping us achieve a reliable long-term surface water management solution for this complex commercial project.

– Ed Carr, Project Manager, R G Carter