Plastic drainage chamber cuts costs and annoyance

Tom Shelley reports on a dramatic reduction in time, cost and trouble by making prefabricated in plastic instead of steel and concrete

A large, bespoke plastic construction for a town drainage system has been made and installed in the centre of a city roundabout in such a way as to minimise disruption to traffic and won a prize for its installers. Had it been made in steel and concrete in the normal way it would have weighed around 100 tonnes instead of just less than four and its installation would have caused considerable inconvenience to the local populace and businesses. Utility contractor Mott MacDonald Bentley was handed the challenge coming up with a way of undertaking some major waster water infrastructure upgrade work will minimising disruption to the local residents of Baildon on the outskirts of Bradford. In order to fulfil the goals of the project, to was decided to relocate a combined storm overflow chamber (CSO) into the centre of the 21m diameter Towngate roundabout. The key to success was a prefabricated plastic 'LightSpeed CSO' made by Newport based manufacturer Asset Management. The completed unit is 2.5m in diameter and 7.5m long and is made of high density polyethylene (HDPE) using 'Weholite' structured wall technology developed by the Finnish company, KWH Pipe. The idea won the contractors a 'Best in Class' award at the Yorkshire Water Business Excellence Awards. The concept is currently being spearheaded by the Welsh Water Capital Alliance in South Wales before its gradual introduction across the UK. It is expected to reduce the overall costs of constructing CSOs by around 30%. The technology is appropriate for pipe based constructions from 400mm to 3m in diameter. Asset International KWH Pipe