Sustainable Drainage Systems
Sustainable drainage systems (SuDS) are a natural approach to managing drainage in and around properties and other developments. SuDS work by slowing and holding back the water. In order to reduce run-off a series of drainage techniques are employed to reduce discharge flow rates and volumes. This reduces pollution and the potential for flooding as well as having amenity and wildlife benefits.
It is important to incorporate a SuDS approach into the original design and layout of a proposal.
Sustainable drainage techniques can be employed in all schemes and the National Park Authority will look for these in application proposals. However, since 6 April 2015 Local Planning Policy and decisions on Major Developments (10+ dwellings, 1,000sqm of floorspace or 0.5ha) there is a requirement to ensure that sustainable drainage systems for the management of run-off are incorporated into the development, unless demonstrated to be inappropriate. The current requirement to prioritise the use of SuDs for all development in areas at risk of flooding still applies.
The SuDS approach will differ with each application and the circumstances of each site.
The implementation of SuDs and their maintenance “to a minimum level of effectiveness” throughout its lifetime are controlled through the planning system. Applications which incorporate SuDs schemes will need to set out how they will be maintained and by which body during their lifetime so that the system continues to provide effective drainage.
Guidance on SuDS can be found from many sources and advice should be taken from Drainage Engineers.
The Authority has adopted the West of England Sustainable Drainage Developer Guide (Somerset area of the National Park) and Sustainable Drainage Systems Guidance for Devon, as technical guidance to assist developers, planners, designers and consultants on the requirements for the design of sustainable drainage systems (SuDS) in the respective areas of the National Park. These documents do not form part of the statutory development plan, but may be a material consideration in the determination of planning applications.
More information about SuDS can also be found on the Susdrain website