Guidance On The Permeable Surfacing Of Front Gardens
To reduce the flooding impact and subsequent pollution of watercourses, new legislation was introduced on 01.10.2008. It is now a requirement that planning permission is required for the construction of a new impermeable driveway, or an extension to an existing impermeable driveway when the surface exceeds five square metres and any surface water is discharged directly on to, or into the public highway. The exceptions to this are:
The new or replacement driveway uses a permeable (or porous) surfacing. This can be gravel, permeable concrete or clay block paving or porous asphalt, with permeable resin bound surfacing included in this.
If the rainwater is directed to a lawn or border to drain into the garden naturally, or directed towards a suitably designed soakaway within the property’s boundary.
Three Key Principles of SuDS and Permeable Paving
To improve water quality
Water quality is improved by filtering pollutants from the water flowing through the system.
To reduce water quantity
The quantity of water flowing into drainage systems and watercourses is reduced by imitating the natural processes of normal water flow. Large volumes of water are dealt with by keeping surfaces clear of standing water and slowly releasing water into the ground, or into traditional systems but at a controlled rate.
To benefit biodiversity/amenity
Sustaining the local water table helps to maintain flora and fauna, and local amenities improve as permeable paved surfaces carries out the necessary drainage function whilst still providing usable spaces such as car parks.