Experts at Polypipe, the UK’s leading manufacturer of plastic sustainable drainage and water management products, have designed a bespoke drainage system for David Wilson Homes’ new development Ashcroft Place, in Thundersley, Essex.

Working closely with the project’s Main Contractor J L Knight, Polypipe was able to provide an effective and easy to install drainage solution, quickly gaining Section 104 approval from the local water authority.

Polystorm-R modular cells, Ridgistorm-XL large diameter pipe and a Hydrobrake flow control unit were all utilised on the site to form a number of attenuation tanks to store surface water and then gradually release it back into the sewer system.

A total of 2,790 Polystorm-R Cells were used to create 5 separate attenuation tanks for the site, with a combined capacity to store up to 558m³ of stormwater. Ridgistorm-XL pipes in 750mm and 900mm diameters, were utilised as single straight runs under the road and 1200mm diameter Ridgistorm-XL pipes were specified by the side of the road to form a bespoke multi-leg pre-fabricated attenuation tank. The completed system has a total length of 650m and was designed in accordance with the Specification for Highway Works and Sewers for Adoption.

Matthew Smith, Buyer at J L Knight, said: “The large scale of this project required a tailored approach, and that’s exactly what Polypipe delivered. By utilising various stiffness classes of Ridgistorm XL we were able to overcome the issue of varying loading and ground conditions, and by combining this with Polystorm-R cells the site is now protected against both 1 in 30 Ridgistorm-XL and 1 in 100 storm events.”

Emma Nicholls, Marketing Manager at Polypipe Civils, added: “Working on a site of this size put our experts’ knowledge to the test. Using their in-depth knowledge - both of drainage systems and water companies’ requirements – the build was completed quickly and economically utilising the wealth of water management solutions available within the Polypipe’s range of attenuation systems, which is the widest available in the UK market.”

Date: 25 March 2015