SuDS should be treated as an early design input on development in Manchester, not a final drainage calculation. Manchester development is frequently delivered on tight urban and brownfield plots. SuDS therefore works best when drainage, landscape, highways and ground investigation are coordinated early, before the developable area and finished levels are fixed.
What matters on a Manchester site
- whether brownfield conditions make infiltration unsuitable or require further investigation
- how runoff will be restricted where a sewer or watercourse discharge is proposed
- safe exceedance routing through dense layouts
- opportunities to combine attenuation, water quality and amenity within limited space
The current drainage framework
For development in England, the 2025 National Standards for Sustainable Drainage Systems set out a runoff hierarchy and design expectations covering flood risk, water quality, amenity and biodiversity. Local planning and flood-risk requirements still need to be addressed for the individual site.
National Standards for SuDS provides the national framework; the project still needs a site-specific strategy and evidence appropriate to the proposed development.
Where infiltration testing fits
If infiltration is being relied upon, testing should be located and designed around the proposed drainage features rather than used as a generic site-wide assumption. Where previous land use or made ground could affect water quality, review the ground-risk information alongside the drainage proposal.
What to send us
Send the site boundary, proposed layout, levels or topographical survey where available, drainage concept, planning or flood-risk comments, and any previous ground investigation. We can then identify whether infiltration testing, drainage support or linked environmental work is needed.
View SuDS, drainage and flood support · View infiltration testing · Ask about a Manchester project