Percolation Tunnels
Please click here to download the Percolation Tunnels SUDS Brochure
Underground drainage system
Designed to work in conjunction with RainRetain rainwater harvesting systems, these multi-purpose tunnels act as a soakaway, or surface water run-off, to replace conventional drainage systems. The system is made up of one tunnel module or several, and two end plates, so it can be sized exactly to meet the required volume.
Why choose WPL percolation tunnels?
WPL percolation tunnels are space saving and cost efficient. They also help contribute to Sustainable Urban Drainage Systems (SUDS) by helping to return run off to the natural environment at, or near, its source.
Benefits
- 300 litres of water storage per unit
- Three-dimensional percolation
- Made from 100% recycled polypropylene
- Lightweight construction
- Easy to handle
- Stackable (up to 40 tunnels per palette)
- Minimal footprint reduces ground excavation
- Fast and easy installation - no need for heavy equipment
- Flexible - combine multiple modules to achieve required volume
- Can be used for attenuation or soakaway applications
WPL's percolation tunnels are suitable for installation under pedestrian or vehicle loading areas (shown below). They can be installed both under lawn (providing there is a minimum of 25cm of earth covering without traffic load) or under a hard standing (providing there is a minimum of 50cm of earth covering with traffic load).
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Dimensions and technical specifications


For RIBA NBS Plus Specification Downloads please click here
Here to Help
We hope you can find everything you need here on our website but if you have any questions, please don't hesitate to call us on 023 92242 600 or email enquiries@wpl.co.uk – we'll be happy to help.











