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 that runs off from a site, allowing natural processes to break down pollutants.
Types of SUDS
- Source control measures deal with run-off at, or close to, the surface where rainfall lands.
- Site control measures manage the surface water run-off from larger areas, such as part of a housing estate, major roads or business parks. The run-off from larger areas can be channelled to a site control measure using swales (shallow drainage channels) or filter drains.
- Regional control measures downstream of source and site controls deal with the gathered run-off from a large area. These systems use the same principles as smaller scale SUDS, but can cope with larger volumes of water. Rainwater that passes through small SUDS can feed into larger SUDS which deal with the gathered run-off from a wide area. It is best to connect the flows between SUDS components with swales, filter drains or ditches and avoid the use of pipes.
Benefits of SUDS
The benefits of SUDS include:
- preventing water pollution
- slowing down surface water run-off and reducing the risk of flooding
- reducing the risk of sewer flooding during heavy rain
- recharging groundwater to help prevent drought
- providing valuable habitats for wildlife in urban areas
- creating green spaces for people in urban areas
You can use the following SUDS techniques:
- green roofs - see green roofs in sustainable drainage systems
- permeable surfaces - see permeable paving in sustainable drainage systems
- infiltration trenches
- filter drains and filter strips - see filter strips and filter drains in sustainable drainage systems
- swales - shallow drainage channels - see swales in sustainable drainage systems
- detention basins, purpose built ponds and wetlands - see detention basins, ponds and wetlands in sustainable drainage systems