Industry pressure paves way for implementation of sustainable drainage

While attention might have been focused on the 99 flood warnings issued by the Environment Agency ahead of the bad weather, there’s a ray of sunshine ahead for the water industry.

After a decade, the government has finally announced it will implement a new approach to sustainable drainage, with the aim to reduce flood risk and clean up rivers.

The sector urged Prime Minister Rishi Sunak, in an open letter last month, to finally commit to implementing Schedule 3 of the Flood and Water Management Act 2010. It looks like they listened.

The new approach to sustainable drainage systems (SuDs) will, according to the government, “reduce the risk of surface water flooding, pollution and help alleviate the pressures on our traditional drainage and sewerage systems”.

The ICE has been supportive of this move for a long time and believes it will be a positive step for in managing flood risk. Let’s talk about why.

What is Schedule 3?

The implementation of Schedule 3 provides:

• a framework for the approval and adoption of drainage systems;
• a SuDs approving body within unitary and county councils; and
• national standards on the design, construction, operation and maintenance of SuDs for the lifetime of the development.

Why is this important?

SuDS use nature-based processes to hold back rain in green features often soaking into the ground rather than contributing to the already overwhelmed drainage system.

The other magical thing is that the process of infiltration traps most of the pollutants in the soil, cleaning the water before it enters the water environment.

The concept has been around a long time - the design of the Dunfermline East Expansion system in Scotland started in the early 1990s.

In England, there’s been a non-statutory approach to encouraging SuDS through the planning system since 2014, but this hasn’t brought about the level of installation required.

Urgent action required

As England is set to see further flooding in February due to a global weather phenomenon called La Niña, coupled with pressure to reduce sewer spills to rivers, urgent action is required.

We need to build as much infrastructure capacity to hold back as much rainwater as possible. Of course, this is only part of the toolkit to solve these interrelated problems.

It’s more difficult to retrofit SuDS in existing cities, though this is an approach increasingly taken by local authorities and water companies to address these challenges.

For example, in Counters Creek in London where below ground storage was incorporated into parking bay design.

What is the expected impact of schedule 3?

The implementation of Schedule 3 will mean we’ll be able to maximise the opportunity of providing capacity in our system when any development occurs.

It will also remove builders’ automatic right to connect new developments with the drainage system, making it conditional on incorporating SuDS as part of the design and identifying the long-term maintenance provision.

Next steps

The government’s agreement to implement the schedule is not the end of the road for our involvement though.

Later in 2023, there will be a consultation on the details of the requirements.

As an industry, we need to engage with this to ensure it’s not possible to use loopholes to avoid this requirement.

We also want to see the standards maximise the benefits these systems can bring to both the drainage network and the design of our communities.

Find out more about Schedule 3