Sustainable drainage systems and the law

sustainable urban drainage system

As a result of factors including urbanisation, climate change and increased house building, flooding is becoming a more regular occurrence in the UK. As a result, the government is looking at ways to mitigate the risk of flooding.

In England, this includes the implementation of Schedule 3 of the Flood and Water Management Act 2010. The framework of Schedule 3 makes the right to connect surface water run off to the public sewer system conditional upon the drainage system being approved before construction work begins.

A review published in early 2023 recommended a mandatory approach to sustainable drainage systems to new developments that will reduce the risk of flooding and associated pollution, and these recommendations are likely to be implemented from 2024.

Alleviating the pressure on traditional drainage and sewerage systems reduces the impact of flooding and helps to keep rivers clean and at a manageable level.

New building developments are known to be one of the reasons for increased surface flooding and sewer pollution. These developments are often built on land which historically provided a permeable surface area, such as woodland, countryside and soil. Such areas would have helped to absorb surface water, thus slowing down the rate at which it entered water courses.

The Department for Environment, Food and Rural Affairs (DEFRA) says that a new consistent approach to sustainable drainage systems (known as SuDS) will be incorporated into new developments. These can include permeable surfaces, soakaways, grassy areas and wetlands. Water reuse systems that store surplus water, such as water tanks and butts, can also be incorporated, to allow water to be re-used, to reduce pressure on the water supply.

A public consultation will now take place before final decisions are made on the scope, threshold and process, as well as the impact these changes will have on developers.