Tesco and others

Background to specification

It may have taken years to gain planning approval, but the £35 million redevelopment of the Northampton site formerly occupied by St Edmund’s Hospital is progressing at a rapid pace – with part of the groundworks taking a fraction of the time expected by locally based contractors Gladstone Construction.

The scheme will see the refurbishment and re-use of some existing buildings, converting the Grade II Listed former Northampton Workhouse building into office accommodation for small businesses, to create a high quality mixed-use development, including a 110-bedroom retirement village, together with shops and facilities for residents.

Like every aspect of the new development, the choice of stormwater attenuation system was designed to reflect innovative thinking in design and materials, with a strong emphasis on new technology and recyclables. Occupying one quarter of the site will be a new Tesco Express with sewers and utilities running beneath the carriageway.

Key criteria

“The carriageway is not adopted by Anglia Water, meaning stormwater must be managed and released into a 9 inch pipe to the main road – which would have cost us weeks if we had used a concrete system,”
says Gladstone director Lee Dicks.

“Using Tubosider’s galvanized steel pipe was a complete eye-opener and had a huge impact on the speed and convenience of installation. It was our first experience of their system, but the first of many, I’d say. The whole system came ready-made to install, with ladder and hydrobrake fitted – you just could not ask for more.”

Solution and benefits

Instead of Lee’s estimate of three weeks to construct a concrete system with a manhole and walled hydrobrake chamber at each end, Gladstone installed two Tubosider tanks of 1200mm diameter in just three days – one to dig out, one to put the sections in place and one to concrete the base.

“And if we’d followed their guidance in full, we’d have saved on the concrete base – Tubosider tanks just need to be backfilled with gravel,” says Lee. “Still, we are absolutely delighted to now know how effective a solution they are.”

The first phase of the Rochmills development should be completed early in 2012, with Tesco taking 85 per cent of the new retail space. Derelict since the hospital closed in 1998, the whole four-acre site should be completed by 2016.