Permeable Paving Simplifies SuDS
Recent innovations with concrete block permeable paving help meet regulatory requirements for sustainable drainage systems (SuDS) while cutting costs and maximising development potential.
By its very nature, concrete block permeable paving is uniquely placed to help meet the multifunctional requirements for SuDS on developments. Its capability to attenuate water flow during rainfall for gradual discharge is well known. But it also provides a fresh opportunity to meet the need for water retention on site – a key element of any SuDS scheme – without additional land-take.
This is achieved by designing with distinct storage ‘compartments’ of permeable paving using straightforward orifice flow controls, that are accessible for observation and adjustment if needed, on the outlets. This enables water storage to be deployed around a site, with flow controls demonstrating compliance to local planning authorities as part of the SuDS design approval process.
Additional storage on valuable land, with associated excavation and construction costs, is avoided and SuDS requirements on high-density urban schemes can be met without expensive storage structures. This approach is also useful for controlling flows to maximise permeable paving storage on sloping sites or to increase treatment times, optimising removal of pollutants within the pavement.
After more than two decades of use, concrete block permeable paving has proved to be a predictable, reliable, and low-cost SuDS technique. Of course, it provides the hard surfaces needed on any project – whether for traffic (including HGVs), parking, pedestrians, or play – but it also creates an inherent drainage system, addressing both flooding and pollution issues by attenuating and cleaning water runoff at source. Concrete block permeable paving can simply enable infiltration to the ground where conditions allow or, more commonly, collect water for transmission to other SuDS features along the ‘management train’ or to conventional drainage.
The National Planning Policy Framework now requires sustainable drainage (SuDS) on new developments of 10 or more dwellings and equivalent non-residential or mixed developments in England. SuDS are also a firm regulatory requirement elsewhere in the UK and local policies spell out what planning authorities expect from sustainable drainage. Designers, developers, and local authorities are increasingly making use of concrete block permeable paving as an essential SuDS technique.
The latest developments with SuDS and urban design are summarised in Interpave’s new ‘Hard Landscape Today’ brochure and a video which dramatically demonstrates the performance of concrete block permeable paving. Both are available via www.paving.org.uk where you can also request regular e:Bulletins from Interpave.
This editorial was brought to you by Interpave, Stand Number F270