Implement 2010 flooding law to ease flood risk and sewage spills, experts tell government

A little-known piece of legislation which Ministers have repeatedly resisted implementing since 2010 should finally be brought into effect in the face of growing flood risk and sewage pollution, more than 40 expert bodies, academics and delivery organisations told Prime Minister Rishi Sunak in a letter on Tuesday.

The group represent expert bodies in town and country planning, construction, drainage, water and environmental management and landscape architecture. They are joined by organisations representing water companies, water customers, environmental NGOs and leading academics in the field.

The Flood and Water Management Act was passed into law in 2010 after serious flooding in the summer of 2007 left 55,000 properties under water and more than half a million without power and mains water.

Yet Schedule 3 of the Act prescribing sustainable drainage systems (SuDS) in new developments was never implemented. Ministers feared the standards and approach it prescribed would hold back the pace of housing delivery and repeatedly resisted taking it forward.

These concerns are misplaced, the signatories argue: SuDS are not difficult to design or build, just different. If incorporated into plans from the outset SuDS can be cheaper to build and manage because they’re not buried underground. And over the decade since the Act was passed the climate, pollution and nature-decline pressures SuDS can manage have ramped-up fast.

Alongside setting mandatory standards for delivery and adoption of SuDS in new developments, Schedule 3 would also end an automatic right builders have to connect into existing sewers. A conditional, SuDS-first approach would ensure new sites don’t overwhelm sewers already nearing capacity with rainwater running off new hard surfaces.

SuDS use ponds, planters, green roofs, tanks, soak aways, tree pits, permeable paving and other structures to manage surface water sustainably. Alongside managing flash flood risk and making sewage spills less likely, SuDS can clean up polluted water running off roads, help bring nature back to towns and cities (and count within government’s ‘biodiversity net gain’ policy) and provide more attractive, heatwave-resilient places to live for local people.

Government has encouraged more SuDS through the planning system since 2014 but this has been based around weak, voluntary standards and no mechanism for their ongoing maintenance once a development is completed. SuDS which have been built are often badly designed and not maintained, meaning they don’t provide the wide-ranging benefits they could to environment and local communities. Last week the government’s own infrastructure advisors recommended the Schedule should finally be implemented.

As the Environment Act passed through parliament last year, Ministers confirmed government would look again at implementing the Schedule. A decision was initially promised by the end of October, but more recently delayed until sometime ‘this Autumn’.

It follows a decade-long debate between policy-makers and practitioners over the importance of SuDS and whether delivery mechanisms worked or not.

A formal approach to implementing SuDS in new development was recommended in the independent Pitt Review of the summer 2007 floods. This was taken forward in the Act with lead local flood authorities gearing-up to act as ‘SuDS approving bodies’.

In 2014 however, housing secretary Eric Pickles announced SuDS would not be taken forward through the Flood and Water Management Act 2010 but instead through the planning system.

In 2016 following amendments tabled by peers and supported by CIWEM, clause 171 of the Housing and Planning Act 2016 required government to carry out a review of the effectiveness of planning policy and legislation in relation to SuDS and development.

In 2017 CIWEM’s ‘Big SuDS Survey’ and ‘A Place for SuDS’ report set out the evidence-base against the effectiveness of the planning-led approach to deliver multi-functional SuDS.

Philip Dunne MP’s Sewage (Inland Waters) Bill 2019-21 championed implementation of Schedule 3 as the Environment Bill 2021’s focus on storm overflows and sewage pollution grew. The resulting Storm Overflows Discharge Reduction Plan confirmed government would publish its review of whether to implement Schedule 3 of the Flood and Water Management Act 2010 in Autumn 2022.

In November 2022 government adviser The National Infrastructure Commission recommended that Schedule 3 should be implemented by the end of 2023.

Terry Fuller, CIWEM’s Chief Executive said: “SuDS were recognised as delivering crucial and wide-ranging benefits in new developments all the way back in 2010. Since then, backward thinking and policies have meant more than 1.5 million new homes have been built in a way which doesn’t manage water well. Meanwhile, climate change-driven extreme weather advances and sewers are full to overflowing.

More than a decade on, it’s time government acknowledged what was known in 2010 and finally brought this piece of law into effect.”

Philip Box, Public Affairs and Policy Advisor at the UK Green Building Council said: “Flooding increasingly represents a serious risk to communities and our built environment across the UK, including across new development. This will continue to get worse as our climate changes.

It is vital that the Government now enacts Schedule 3 of the Flood and Water Management Act 2010 to avoid condemning us to higher future flood risk. This will be essential to ensure sustainable drainage systems (SuDs) of sufficient quality become the norm across new development in England.

UKGBC and our members have long-supported and highlighted the benefits of SuDs, as when well-designed, they can be crucial to delivering a wide range of benefits, from protecting new development to enhancing biodiversity net gain.”

Dr Louise Walker, Senior Research Manager at CIRIA said: “Good management of surface water presents huge opportunities to reduce pollution, reduce flooding, increase biodiversity, and provide beautiful blue and green spaces with all their health and wellbeing benefits.

CIRIA and susdrain have years of accumulated knowledge to prove it. These opportunities have been overlooked for 12 years. Climate change should now be considered in every legislative decision made. Implementation of Schedule 3 is a prime opportunity to adapt by having good surface water management in all new developments. It would be reckless to miss yet another opportunity.”

Graham Fairhurst, Chair of Susdrain said: “Susdrain represents the wide stakeholder community which has the body of knowledge to make this happen and is ready to play its part.

SuDS are critical to our ability to address the impacts of climate change. All we need is the underpinning legislation in place to enable this to happen.”