Using SUDS to manage pollutants

Sustainable drainage systems (SUDS) offer a useful mechanism for managing pollutants on-site and removing the burden for treatment in the wider water system.

Bristol Business Park sustainable drainage system. Photo by Stephen McLaren.

Sustainable drainage systems (SUDS) can work by filtering out pollutants through a series of features such as balancing ponds and catchment basins. They can most effectively be designed at the neighbourhood scale.

Actions that can support surface water management at the neighbourhood scale include:

• retrofit catchment basins to allow some drainage into planting areas which can perform natural filtering roles
• adequate source control/pre-treatment in SUDS requirements to ensure clean water flows for all new development or redevelopment
• the combined and storm sewer ceasing to receive run-off wherever possible and only at ‘greenfield rate’ (the site should have the equivalent run-off as if it were a greenfield) in the future
• surface watercourses replacing below ground systems wherever possible to allow informal policing of run-off discharge and to provide surface cleaning in wetlands and natural watercourses.
• a clear SUDS planning, design, construction, adoption and maintenance sequence for all development.

Such actions should inform local planning guidance and wider water management strategies.

Priority: encourage sustainable water use
Tags: water, neighbourhoods