David Wilson Homes’ large-scale Ashcroft Place development in Thundersley, Essex, required a bespoke Sustainable Urban Drainage System (SuDS) to meet Section 104 requirements. As water management experts, Polypipe Civils & Green Urbanisation [Polypipe CGU] was able to provide an effective and easy-to-install solution for the project’s main contractor, J L Knight, which quickly gained Section 104 approval from the local water authority.

Polystorm-Xtra and Polystorm-R modular cells, Ridgistorm-XL large diameter pipe and a Stormcheck flow control unit were all utilised on site, forming a number of attenuation tanks to store surface water to ensure it can be gradually released back into the sewer system.

A total of 2,790 Polystorm-R cells were used to create five separate attenuation tanks for the site, with a combined storage capacity of up to 558m³ of stormwater, while Ridgistorm-XL pipes in 750mm and 900mm diameters were utilised as single straight runs under the road, with 1200mm diameter Ridgistorm-XL pipes installed by the side of the road to form a bespoke multi-leg, pre-fabricated attenuation tank.

Polystorm Xtra - Housing - Attenuation - David Wilson Homes Kiln Road Essex -Image 11.jpg

Polypipe CGU designed and manufactured Ridgistorm-XL in a variety of stiffness classes in order to overcome the issue of varying loading and ground conditions. Taking this approach, and by combining this with Polystorm-Xtra and Polystorm-R cells, means that the site is now protected against both ‘1 in 30’ and ‘1 in 100’ storm events.

The completed Ridgistorm-XL large diameter pipe system has a total length of 650m and was designed in accordance with the Specification for Highways Works and Sewers for Adoption.