Too much water. Not enough water. These seemingly opposing challenges are becoming defining issues for the built environment. As the Environment Agency warns of a potential five billion litre-per-day water deficit by 2055, the UK is also experiencing increasingly intense rainfall events that place growing pressure on drainage infrastructure. The result is an emerging challenge for architects and designers: creating developments that can cope with both flood risk and water scarcity.
In response, sustainable drainage systems (SuDS) are increasingly being viewed as more than a flood management tool. They are becoming a cornerstone of climate-resilient design, helping developments manage water quantity, improve water quality, and support wider environmental outcomes.
Water as a resource
SuDS have become a fundamental part of modern developments, helping to manage surface water runoff while reducing pressure on historical drainage networks. However, their role extends far beyond simply controlling the quantity of water leaving a site.
At their core, SuDS are built around four key principles: water quantity, water quality, amenity and biodiversity. These pillars collectively encourage a more holistic approach to drainage design, ensuring that developments not only reduce flood risk but also create healthier, more resilient environments.
For architects, this philosophy presents an opportunity to integrate water management into the wider design narrative of a project. Rather than viewing rainfall as something that needs to be removed as quickly as possible, SuDS encourage designers to consider how water can contribute to placemaking, ecological enhancement and long-term climate resilience.
From quantity to quality
Managing water volumes remains a fundamental part of SuDS design. Engineered systems such as attenuation tanks play a vital role in reducing flood risk, slowing runoff and protecting public drainage infrastructure from increasingly intense rainfall events.
As development sites become more constrained and project requirements more complex, there is also growing demand for solutions that provide flexibility without compromising performance. Solutions such as Aquacell NG, Wavin’s latest attenuation tank, have been developed with this in mind. Its modular design enables systems to be adapted to suit the specific requirements of a project, helping designers create tailored drainage strategies that respond to individual site conditions.
However, the ability to retain water is only one part of the wider challenge.
As interest grows in making better use of rainfall within developments, increasing attention is being paid to the quality of the water entering these systems. After all, retaining water for longer becomes significantly more valuable when that water is cleaner and better suited to supporting wider environmental objectives.
As surface water moves across roads, car parks, roofs and other hard surfaces, it can collect sediments and pollutants before entering drainage infrastructure. Without appropriate treatment, these contaminants can affect the performance of downstream drainage assets and limit opportunities for water reuse and reduce the environmental value that SuDS can deliver.
The introduction of Wavin Certaro Lamella Hydrodynamic Separator (HDS) reflects the industry’s growing focus on water quality as a critical component of sustainable drainage. The advanced separator filters water from drains before it enters accompanying attenuation tanks, capturing finer particles and significantly improving the quality of stored water to make it cleaner and safer for potential reuse.
By combining lamella technology with hydrodynamic separation, Wavin’s new HDS delivers high-performance sediment separation within a compact footprint. This makes it particularly well-suited to locations where space is limited but the need to improve water quality is urgent. Designed to help the industry meet stricter environmental standards without compromising space or budget, this HDS is also cost-effective, quick to install, and simple to maintain – making it a smart, sustainable choice for modern drainage infrastructure.
Closing the water loop
The future of sustainable drainage lies in recognising that water is a resource, not a waste product.
Effective SuDS are not simply about removing water. They are about managing it in a way that supports resilience, environmental performance and long-term value.
For architects, that means considering water quantity and water quality together from the earliest design stages. By taking a more holistic approach, developments can move closer to a genuinely circular water strategy, unlocking greater value from surface water while creating places that are better prepared for a changing climate.
For more information on Wavin’s latest SuDS offering, visit wavin.com/gb/solutions/urban-climate-resilience
By Blair McDonald, Commercial Manager for Urban Climate Resilience at Wavin