A week after the new NPPF made Defra’s National Standards the named rulebook for sustainable drainage, the paperwork has caught up. Tucked into the Chief Planner’s Planning Update Newsletter of 18 August 2026 is a practical announcement that will touch almost every planning application with drainage implications: the Environment Agency has published national SuDS Strategy Templates, produced with CIRIA, the Association of SuDS Authorities (ASA), Arup and a working group of SuDS practitioners.
The stated aim is disarmingly simple: help applicants “submit the right information on SuDS first time”, and make it easier for local planning authorities and Lead Local Flood Authorities to check whether a proposed drainage system has been designed in accordance with Defra’s National Standards for sustainable drainage systems.
Two templates, picked by scale
To reflect the proportionate approach in the new National Planning Policy Framework, there are two versions:
- a SuDS Strategy Template for Major Development — broadly, schemes of 10 or more homes or the non-residential equivalent; and
- a SuDS Strategy Template for Non-major Development — everything smaller, where a full major-scheme strategy would be overkill.
Applicants are told to pick the template that best fits the scale of the proposal, and to download it fresh each time from the Planning Portal or the CIRIA website so they’re always working from the latest iteration rather than a saved copy.
Why this matters more than it sounds
Templates are rarely news. This one is, for two reasons.
First, the Environment Agency is explicitly encouraging LPAs and LLFAs to adopt the national templates and drop locally produced versions. Anyone who submits drainage strategies across several authorities knows the current reality: each LLFA has its own pro-forma, its own appetite for detail and its own pet requirements. A single national format — like the standardised decision-making policies in the new NPPF — is aimed at squeezing out exactly that local variation.
Second, a standard form cuts both ways. It tells you precisely what to include, and it makes what’s missing impossible to hide. Expect the template to walk through the things the National Standards already ask for: where your site sits on the discharge hierarchy (reuse, then infiltration, then a watercourse, then a surface water sewer, with a combined sewer strictly last), the evidence behind that choice, runoff rates, storage volumes, the treatment train and the maintenance arrangements. A drainage strategy that asserts “infiltration is not viable” without percolation test results to show for it is going to look thin in a box that asks for the data.
For anyone sizing soakaways, that means the familiar routine — trial pits and infiltration testing to BRE Digest 365, storage checked across a range of storm durations at the design return period with a climate change uplift — is no longer just good practice. It’s the evidence the checking officer’s form now expects to see, in the place they expect to see it.
Free SuDS training for planners
Alongside the templates, the Environment Agency and the Town and Country Planning Association have launched a free, interactive e-learning module on securing good SuDS through planning, developed with experts from ASA and with input from CIRIA and CIWEM. It’s aimed at planners and flood-risk practitioners, self-paced, and open to anyone to register. If the person determining your application has just done a course on what a compliant SuDS strategy looks like, it’s worth knowing what they were taught.
The bigger picture
This lands as part of a deliberate sequence. The August 2026 NPPF’s policy F8 requires SuDS on all development with drainage implications to be designed in accordance with the National Standards; Schedule 3 of the Flood and Water Management Act stays uncommenced, with the government betting instead on this strengthened planning-led approach. Named standards, a national submission format, trained checking officers — the direction is consistent, and it all points to drainage strategies being marked against a rubric rather than negotiated case by case.
The practical advice is unchanged but sharper: test early, and test properly. An infiltration rate assumed at layout stage and disproved at discharge-of-conditions stage still means a redesign — only now the gap will be visible on a standard form at validation rather than surfacing quietly later.
SoakMonkey runs the BRE Digest 365 soakaway method in your browser — infiltration rate from your percolation results, storage sizing tested across storm durations, and a Building Control-ready report to drop straight into your SuDS strategy. Sizing on screen is free; the PDF export is £25 +VAT (£30 inc VAT).
And if a planning condition is asking for a SuDS strategy to the National Standards and you’re not sure how your site will behave, get in touch — a trial pit and an hour of sizing usually settles it.
Sources: Planning Update Newsletter, 18 August 2026 — Letter from MHCLG to Chief Planning Officers, GOV.UK · National standards for sustainable drainage systems (SuDS), Defra, GOV.UK · Introduction to SuDS for Planners (free e-learning), TCPA