Renowned developers Taylor Wimpey called upon Polypipe Civils & Green Urbanisation [Polypipe CGU] to provide an engineered drainage solution, designed to work with a sloping gradient found on the site of a new luxury residential development.

Set in the idyllic countryside town of Houghton Regis, the Regent’s Place large-scale residential development comprises of a mix of 180 two, three and four bedroom houses, nestled in a tranquil area that offers stunning views of the landscape.

The landscape surrounding the development features a large public open space with limited footprint for drainage design and sloping gradients. Taking on the challenge, Polypipe CGU worked closely with Taylor Wimpey and consultant engineers JPP Consulting to design a stormwater solution, which incorporated staggered legs to take site conditions into account, that also met site requirements and adopted elements laid out under Section 104 agreement for approving water company, Anglian Water.

The attenuation tank supplied for the project boasts a 3m diameter offset RidgistormCheck Vortex Flow Control Chamber which controls discharge water from the tank at an agreed rate of 10 litres per second, so the local watercourse is not overwhelmed. To control additional flow when required, the chamber also features a penstock flow control.

Ridgistorm-XL - Housing - Residential Section 104 - Taylor Wimpey Regents Place Houghton Regis - Image 5.JPG

The development required a below-ground stormwater solution able to store up to 2,052m³ of surface water run-off to cater for both ‘1 in 30’ year and ‘1 in 100 plus 30% climate change’ year storm events.

Polypipe CGU supplied more than 500 metres of Ridgistorm-XL to form 14 pipe runs in 2100mm diameters. The Polypipe CGU technical team engineered designed the pipe to ring stiffness SN2 to meet the ground conditions, burial depths, native soil pressures and loading on site. The system was tested to pass required deformation and buckling checks in accordance with BS EN 1295-1.

Accompanying the pipe runs, the Ridgistorm-XL system incorporated 34 pre-fabricated modularised fittings which included 90° bends and ‘F’, ‘T’ and double ‘T’ fittings to fit the limited on-site dimensions perfectly.

The socket and spigot nature of these engineered fittings kept jointing to a minimum allowing for easy pipe alignment and speedy installation using electro-fusion jointing. This, in turn, significantly reduced on-site installation time and cost.

Polypipe CGU has worked on many residential projects in the past and understand the implications surrounding routine maintenance work. In order to make maintenance work less strenuous and overall safer for installers, Polypipe CGU supplied 10 RidgistormAccess Manholes in 1200mm and 1800mm diameters to assist workers with easy access to a pipeline.

Keith Millard, Senior Engineer at Taylor Wimpey, said: “Polypipe CGU designed the required stormwater attenuation system to not only fit the available area, but also saved us time and costs on the installation by delivering the system and fittings as one piece modular units ready to install.”