Rainwater Interception System

Rainwater Interception System for Commercial and Public Buildings roofs and podiums

As space becomes even more limited in the urban environment we need to look to more sustainable ways of managing the flow of rainwater. By using Polypipe water management and source control systems for roofs and podiums, in conjunction with trusted Terrain drainage systems, building services designers can utilise these areas to integrate effective water management at source and control the flow of water at a designated rate into the below ground drainage system.


Dealing with Rainwater run-off


Reducing rainwater run-off adds significant value to Sustainable Urban Drainage Systems (SUDS). By intercepting rainwater at source, it can be used as a resource. The majority of rainfall events in the UK may be less than 5mm in depth, however on the occasions when the depth is much higher, existing systems can struggle. In order to cope with heavier rainfall, you’ll need surface-based systems to provide storage, treatment, flow control, evaporation and passive irrigation. Each of these systems is critical to the performance of source control drainage systems.


The Rainwater Interception System comprises of the following components:


  • High strength modular cells
  • Robust geotextiles (to provide treatment)
  • Geomembranes
  • Rainwater outlets incorporating flow control devices and engineered Terrain Soil and Waste PVCu and HDPE systems


It can enhance the effectiveness of both ‘green’ and ‘brown’ roof applications, and can even provide a ‘blue’ roof attenuation system. Due to the inherent strength of permavoid modular geocellular units, this system can be incorporated into a wide range of SUDS solutions.


To find out how our Rainwater Interception System could benefit your commercial building please call our Technical Team on 01622 795200.

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For further information please see our Applications & Benefits and Roof Applications pages.


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Tall Buildings Brochure

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Rainwater interception system

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If you’re looking for sub base applications please see our Civils and Infrastructure pages