SuDS and Flood Risk: What Architects Need to Know
Architects are entering a new era of responsibility. With the planning system tightening its environmental focus in 2025, flood risk and sustainable drainage systems (SuDS) are no longer side notes in design. They now sit at the heart of planning approval, shaping whether a project moves forward or stalls.
The new National Flood Risk Assessment (NaFRA2) is redrawing the flood map, identifying more areas at risk from rivers, seas and surface water. At the same time, the National Standards for SuDS, introduced in June 2025, have elevated drainage to the level of critical infrastructure. Local Planning Authorities are responding with stricter scrutiny and expect architects to front-load water management and climate resilience into their designs from the very beginning.
For architects, this means SuDS can no longer be treated as an afterthought. Designs must now actively manage rainfall, improve water quality and deliver ecological and social value. Rain gardens, green roofs, swales and permeable paving are expected to feature in early-stage concepts. Detailed surface water management plans, complete with calculations, flow controls, attenuation features and maintenance strategies, are becoming core requirements.
Recent projects highlight the risks of doing too little. In Ipswich, a new aquatics centre faced objections because its drainage relied only on permeable paving and an attenuation tank. The scheme was deemed insufficient for biodiversity and amenity value, falling short of the higher bar now set by planning authorities. This case shows clearly that tokenistic drainage solutions will no longer pass muster. Multifunctional SuDS that deliver resilience, environmental value and placemaking benefits are the new expectation.
The opportunity for architects lies in embracing this shift. Embedding SuDS design from the earliest planning stage, using NaFRA2 data to assess flood risk accurately and demonstrating resilient layouts are all steps that strengthen both design quality and planning success. Resilient buildings might include raised habitable spaces, flood-compatible ground floors or landscape strategies that double as natural drainage systems. By engaging with specialists early, architects can anticipate objections and unlock creative, water-sensitive solutions.
Ultimately, 2025 marks a fundamental change in planning practice but it is also a chance for architects to lead. Our consultants are here to support your projects and ensure they are compliant, resilient and ready for planning approval.
Who to Contact:
Emily Challender
Emilychallender@geosmartinfo.co.uk
01743 664098
www.geosmartinfo.co.uk
