The Magic Number

Can DEFRA get Schedule 3 over the line and make 2024 the year of Biodiversity and SuDS?

At the beginning of last year, the UK government finally announced their ‘commitment’ to implementing Schedule 3 of the Flood and Water Management Act 2010. As Spring appears, and the storms show no signs of abating, will this commitment ever become a reality? Gordon Brown was Prime Minster when DEFRA began drafting the first metric for Biodiversity Net Gain, and there have been five Ministers for the Environment since 2020; the SuDS community has been patiently waiting for action. What does Schedule 3 even mean? We don’t have all the answers at R-LA, but we hope we might shed some light on the whole matter. 


What is schedule 3? A Potted History of Policy
Schedule 3 was a framework for the approval and adoption of sustainable drainage systems (SuDS) for new developments that was written into the Flood and Water Management Act 2010. However, it was never implemented in England. SuDS were redirected to the National Planning Policy Framework (NPPF) where they have been encouraged but not enforced. A Jenkins Review in 2020 raised concerns about unsatisfactory standards of design and construction, and of the difficulties of ensuring proper maintenance once the developer had left the site.  

In January 2023, the government announced its ‘commitment’ to implementing Schedule 3 in the UK. This would mean that SuDS would become the default option for surface water drainage on new developments (more than 10 houses). Schedule 3 would remove a new development’s previously automatic legal right to connect surface water drainage to nearby sewage infrastructure. The design, construction, operation and maintenance of these systems would be approved by a SuDS Approving Body (SAB) before any construction on site.  

Why is it important?
As landscape architects, we believe this is a crucial step for all developments to help relieve the pressures of climate change, reduce surface and sewer flood risk, improve water quality and harvest rainwater to meet current and future population demands.

Flooding in the UK
Whilst flooding seems to be constantly in the news at the moment, we have always talked about the risk from rivers, seas and groundwater. What has changed over the last decade is the risk of surface water flooding; when all four risks are at play, landscapes can be dealing with unprecedented volumes of water. 

Cast your minds back to the summer of 2007, when the UK suffered what was reported to be the worst flooding since records began with some corners of the country receiving four times the average amount of rain. Surface water and river flooding affected more than 55,000 homes and businesses across the country, 7,000 people were rescued, 17,000 families had to leave their homes and 13 people died (Environment Agency, 2007). The economic damage of these floods is thought to have been between £2.5 billion and £3.8 billion, (Defra, 2010).

This national catastrophe sparked a review ( Pitt Review 2008 ) into the country’s management of flooding. The review went on to identify SuDS as an effective way to reduce the risk of surface water flooding and the burden on sewer systems. Despite this, Schedule 3 fell away from the Flood and Water Management Act, which was passed in April 2010.