Recently opened after just 10 months from start to finish, the newly built 80,000 sq ft Tesco Superstore in Hanley, Staffordshire is another feather in the cap for contractors VINCI Construction UK– part founded on the steel Twinstore stormwater attenuation system recently innovated and patented by Tubosider. VINCI Construction UK’s Retail & Interiors Division are industry specialists in supermarket construction (with several more projects already on the books for next year), but this has been their first with Twinstore, says project manager Rob Symons.
“Although a crate system was specified on the tender drawing, we soon recognised that Tubosider had devised a steel tank based solution with the potential to save us and the client a significant amount of time, money and aggregate to install it with – all told, around 15% less cost than projected.”
Originally designed to better thermoplastic chambers on void performance and space with, patented Twinstore tanksare now winning out over conventional systems by achieving gross volume through a combination of pipe structure and void ratio in the backfill. Severn Trent Water stipulate particularly high attenuation levels and extremely strict outflow and hydroflow rates.
Installed over 50 yards away across an access road, the 2200 m³ (77692 ft³) tank serving the new £50 million store meets the attenuation needs of a 720 bay car park. For easy inspection and maintenance, it is constructed in eight legs of 1800mm helibore pipe fitted with strategically placed manholes for access. Doubling the size of the old store and creating 300 new jobs, including its petrol station, the new store took a record seven days to fill.
“Quality is a priority for Tesco in all of its operations, and VINCI Construction UK will certainly be recommending Tubosider for future stores,” says Rob Symons. “Furthermore, their support is excellent, from design and procurement through to delivery. And although they recommended a named drainage contractor to install our first system, we soon recognised it is quite straightforward and needs no special expertise – in future we will be doing it all ourselves.”