In a significant step toward building climate-resilient communities, the UK government has issued comprehensive National Standards for Sustainable Drainage Systems (SuDS)—a milestone for planners, developers, engineers, and environmental professionals. These standards represent a shift from traditional drainage to a natural, multi-functional approach that puts sustainability and environmental performance front and center.
Why These Standards Matter
Surface water runoff—if poorly managed—can lead to flooding, water pollution, and loss of biodiversity. The new standards guide the design, construction, and maintenance of SuDS to ensure that water is managed where it falls, mimicking natural processes and delivering multiple long-term benefits.
Applicable to new developments (greenfield and brownfield), these standards do not target retrofits directly, though they may serve as a helpful framework. Importantly, the standards apply to uncontaminated rainwater runoff, with stricter controls for higher-risk land uses.
The Structure of the Standards
The framework consists of seven integrated standards:
- Runoff Destination – Follows a priority hierarchy: from rainwater reuse to infiltration, then to water bodies, sewers, and lastly, combined sewers.
- Interception of Everyday Rainfall – Encourages solutions like green roofs and permeable paving to manage the first 5mm of rain on-site.
- Management of Extreme Rainfall – Requires robust flood protection designs accounting for climate change and urban creep.
- Water Quality – A SuDS management train must reduce pollutant loads to protect ground and surface waters.
- Amenity – Promotes green, usable public spaces with dual functions such as recreation and drainage.
- Biodiversity – Designs must enhance ecological networks and support habitat creation.
- Construction and Maintenance – Systems must be buildable, maintainable, and durable over the lifecycle of the development.
Each standard is backed by a suite of principles and detailed requirements, including risk assessments, stakeholder collaboration, and long-term maintenance planning.
What we belive is Missing
Firstly, scanning through the online document there is mention of needing oil interceptors on high-risk sites, however no mention of the greater and ever-present risk to SuDS from firewater, the potentially toxic and highly pollutive runoff from firefighting. This is where the document should be linked to CIRIA 736F and other similar documents that deal with the risks from spills and firewater and the call for pollution containment systems such as the EIL Flapstopper.
Secondly, there is no mention of Smart SuDS. This is where the performance of an existing SuDS feature, or a new one is optimised to improve storage and control the time of the discharge to ensure that it doesn’t coincide with the peak flows in the receiving water. This typically comprises of a downstream sensors and real-time telemetry linking back to a control actuator such as RDNs Wastewater Flow regulatorwhich through its solar operability ticks one of the standards big boxes in the area of net zero.
From Regulation to Real-World Impact
Back to the Standards. Tehese standards are more than just regulatory guidance—they are a blueprint for integrating water into the fabric of urban life. SuDS designed under these standards offer:
- Reduced flood risk
- Improved water quality
- Urban cooling and greening
- Enhanced biodiversity
- Community wellbeing
Critically, early engagement with planning authorities and other stakeholders is essential. The standards align with planning policies, biodiversity net gain (BNG) requirements, and regulatory frameworks such as the Environment Act 2021 and Flood and Water Management Act 2010.
Final Thoughts
The message is clear: water is not waste—it’s a resource. By adopting SuDS in line with national standards, we can build developments that are resilient, sustainable, and nature-positive.
What is missing the benefits and advantages of Smart SuDS in reducing cost and improving the impact on receiving waters with respect to flooding. Then there is firewater this needs to be added to all risk assessments and the fitting of appropriate containment systems fitted to protect SuDS.
As urban pressures grow and climate risks intensify, SuDS are not just good practice—they’re essential infrastructure.