Defra mandates SuDS

The mandatory inclusion of sustainable drainage systems (SuDS) in all new developments has been approved following a review by the Department for Environment, Food and Rural Affairs (Defra), with implementation expected from 2024.

SuDS have been highlighted as a key way to address the pressures of climate change, population growth and urbanisation as well as reducing surface water flood risks and prevent sewer networks from being overwhelmed.

Government has agreed to implement Schedule 3 of the Flood and Water Management Act, which also removes developers’ automatic right to connect surface water runoff to the public sewer network. Going forward, connection will be conditional upon the drainage system being approved before construction work begins.

The water sector, which has long campaigned for SuDS to be mandated and an end to the automatic right to connect, has warned the move does not go far enough and called for more action to be taken based on recommendations by the Storm Overflows Taskforce.

Secretary of state for Defra, Therese Coffey, said the move will “maximise the opportunity to improve the resilience of our infrastructure and environment response to climate change whilst realising many other benefits”.

Government will now consider how to implement Schedule 3 in England, which has been in place in Wales since 2015. Current planning policy requires SuDS to be included in flood risk areas and major developments over 10 homes unless there is clear evidence this would be inappropriate. However a 2020 review, ahead of Defra’s decision today, concluded the planning-led approach was not working.

The report also stressed that successful implementation of Schedule 3 “will require professionals with the skills and knowledge to design, construct, assess and maintain SuDS.”

It recommended that actions need to be taken to make sure knowledge, skills and capabilities to deliver and maintain SuDS are developed and shared.

The water sector has long been calling for mandatory SuDS to be implemented. A spokesperson for trade body Water UK, described it as “a welcome step forward and something the industry has been pushing government to implement for some time.”

However, they added there is more to be done: “This is only one of several vital policy changes recommended by the government’s Storm Overflows Taskforce to accelerate the improvement of overflows. Alongside the £56 billion of new investment from water companies, Government must implement all of the taskforce’s recommendations if we are to truly transform the health of our water environment.”

Last month, the National Infrastructure Commission (NIC) gave government a series of recommendations to mitigate the risk of surface flooding, including to implement SuDS.

Commissioner Jim Hall said of today’s report: “Making sustainable systems the default for new developments and introducing a more consistent approach to design will help address the problem at source. It makes both economic and environmental sense and, while we await further details and the outcome of the forthcoming consultation, this is undoubtedly a positive move which we hope can be brought into practice as soon as possible.”

Defra’s long-awaited response following a consultation last year was also welcomed by Philip Dunne, chair of the Environmental Audit Committee, who said: “Our drains and sewers are spilling under significant pressure, exacerbated by new housing developments having the automatic right to connect to the sewerage system. It is absolutely right that the Government leaves no stone unturned to address the major and complex challenge of easing pressure on the system.

“Its intent for new developments to include sustainable drainage systems is absolutely the right direction, and was a key recommendation in our report that considered water quality. Developers must not simply have the right to connect to an overloaded sewerage system and not contribute to improvements.”