The water industry is unusual in the plethora of parties who play a role in the management of foul, rain and storm water. But this challenge can best be met by partnering with a supplier with experience of all, argues Marshalls Civils & Drainage managing director Paul Curtis.
In a bid to improve flood resilience and water quality, the UK Government has confirmed (January 2023) that all new developments in England will need to be fitted with sustainable drainage systems (SuDS).
The Department for Food, the Environment and Rural Affairs (DEFRA) has confirmed that this mandate is in the pipeline and will be implemented through changes to the 2010 Flood and Water Management Act. The aim is to alleviate pressures on drainage and sewerage systems by ensuring that natural drainage patterns can be better replicated in developed areas, through measures including permeable surfaces.
Late 2022 was marked by increasingly common weather practice – droughts followed by flooding. The first three quarters were the driest on record since the summer of 1976, according to the Met Office. This prompted interventions from water companies, with most regions declaring drought.
This meant that when heavy rain did arrive in the last quarter of 2022, soils were so dry the water could not be absorbed in enough time and flooding occurred in several regions – in Dorset in October, November and December. November also saw flooding in Tenby, Wales; Angus, Scotland; and Nottingham, Loughborough, Coventry, Wolverhampton and Wiltshire in England. The year ended with severe flooding in Dumfries, Scotland.
In December 2022, the UK Green Building Council wrote to Prime Minister Rishi Sunak noting that at least 3.2 million properties are at risk of surface water flooding in the UK and that floods already cost an average of £1.3 billion per year in damages alone. It reminded the Prime Minister to heed the Government’s own Climate Change Risk Assessment, which recognises flood risk as the UK’s highest-level climate threat.
So, it’s obvious that the issue of water management in the UK is of vital interest to all of us. But it’s a complex and diverse issue.
With National Highways responsible for the water management of roads and highways, the Environment Agency responsible for rivers, coastal and open water courses, and UK water companies for the water management of homes, sewers, public realm and infrastructure projects, there is an incredibly diverse range of needs and wants.
While Scotland has one publicly owned water and sewage company (Scottish Water), there are 18 water companies in England and Wales, 10 of which have licenses to provide water and sewage services, with the remainder providing water services only.
So, finding a supplier that offers trusted long-term solutions to multiple aspects of water management – flood protection, stormwater, rainwater harvesting and wastewater treatment – would go a long way to countering this.
The impact of flooding in particular can be devastating to both individuals and communities, as well as having social, economic and environmental consequences. So, reducing the risk and mitigating the impact through suppliers that can visualise and implement the bigger picture should take priority.
Couple this prolonged rainfall with an ever-increasing population, with more and more vehicles clogging up the road network, and the fact that many existing water management systems, some of which were built in Victorian times, need replacement, and you have a “Perfect storm” waiting to happen.
Add that the decreasing availability of land to build on means that new housing developments and infrastructure are being built on flood plains and flood risk areas and the menace only grows. Developers and stakeholders should be building with a mindset that flooding WILL happen at some point, rather than it MIGHT.
DEFRA’s White Paper “Water for Life” estimates an average 800 years’ service life requirement for sewers in England, so it’s obvious there is an urgent need for long-term drainage solutions.
This is where water management systems manufacturers that can offer end-to-end integrated water management solutions, with products and systems that intercept, infiltrate, attenuate, treat, convey, release and protect from surface, flood, foul and stormwater drainage, come into their own.
Just because their remit includes all of these factors doesn’t make them jacks of all trades. Many have grown their business by acquiring specialist suppliers, rather than choosing to grow organically and learn new practices along the way, and are therefore uniquely placed to help customers in every factor of their water management strategy, from pre-planning design to the supply and installation of products.
Early engagement in projects often means they can offer an integrated water management design to please all stakeholders, by saving on times and costs. This can include permeable paving and CKD products, through to below ground drainage solutions, including sealed manholes.
DEFRA’s sustainable drainage systems review looks to ensure such systems are designed to reduce the impact of rainfall on new developments by using features such as soakaways and permeable solutions, reducing the overall amount of water that ends up in the sewers and storm overflow discharges.
The agency is now preparing to launch a consultation on the changes to fine-tune its approach. Mandates are then set to come into effect in 2024. In the meantime, the department will assess potential burdens on developers and how they should be managed, including improving SuDS-related skills across the built environment sector.
It has heard evidence that there are not, at present, specific regimes to check whether developers have constructed SuDS as agreed. It is, therefore, seeking to move past its current “planning-led” approach with non-statutory technical standards and increased checking rules and maintenance rules for developers.
It is also proposing that the requirement for SuDS to be fitted in new developments is broadened as currently it only applies to developments of more than ten homes. A broadening would cover smaller developments, and developments in urban areas for non-domestic use.
It has not yet assessed the topic of retrofitting SuDS in existing developments. The Department claims this lies beyond the remit of the legislation and regulation set to be changed.
