SuDS in England from 2026: what changes for drainage product specification

What actually changed

• National standards (2025). Defra published national standards for sustainable drainage in June 2025 (updated July 2025). They replace the thin 2015 non-statutory technical standards with standards on runoff destination, everyday and extreme rainfall, water quality, amenity, biodiversity and whole-life maintenance.
• Planning policy (August 2026). Policy F8 of the revised NPPF asks for drainage designed in accordance with those standards, and a SuDS statement is listed as a national validation requirement.
• Schedule 3 — still not commenced in England. The statutory SuDS approval body regime from the Flood and Water Management Act 2010 is in force in Wales but not in England; the government has said a decision will be made "in due course".

What it means on site

Because the standards push water to be managed close to where it falls, designs lean more heavily on infiltration where soils allow, attenuation where they do not, and permeable surfaces instead of piped-only solutions. Expect more specifications for:

• geocellular attenuation and soakaway modules with defined load classes;
• permeable gravel/grass grids for parking and access;
• green and blue roofs, and therefore drainage/retention boards;
• maintenance access — inspection modules and silt management.

Procurement checklist

1. Get the load class and cover depth from the drainage designer before comparing module prices.
2. Ask suppliers for test reports (vertical and lateral load) and any third-party approvals your adopting authority expects.
3. Confirm wrap type — geotextile for infiltration, geomembrane for attenuation.
4. Plan maintenance access — it is part of the standards, not an extra.