NPPF August 2026: What Changed for Flood Risk & Drainage

The headline: flood risk now has its own chapter, and more sites need an FRA

On 17 August 2026 the Government published a new National Planning Policy Framework for England, replacing the December 2024 version in full. It applies to planning decisions from that date — including applications that were already submitted but not yet determined. For anyone building, converting or developing where there is any flood risk, the changes are significant enough that reports written against the old Framework can now look out of date.

Having spent years reviewing applications from inside a Lead Local Flood Authority, my reading is that the direction of policy hasn't shifted — flood risk hasn't been relaxed — but the way it is organised, referenced and evidenced has. Applicants who understand the new structure will find it easier to get through; those still quoting the old paragraph numbers will find themselves asked to resubmit.

What's actually changed

1. A dedicated flood risk chapter, with coded policies F1 to F9

Flood risk and coastal change now sit in their own chapter — Chapter 18, "Managing flood risk and coastal change" — as nine numbered policies, F1 to F9. The whole Framework has been restructured so that every policy carries a code, with a clearer split between the policies used to prepare local plans and the national decision-making policies applied to individual applications. For an FRA that means a defined set of national tests to address head-on, rather than a scattering of paragraphs.

2. The flood zones and vulnerability tables are now inside the Framework

A new Annex F carries the flood zone definitions (including the Zone 3a / 3b split), the flood risk vulnerability classification and the zone-compatibility table. Until now these lived only in Planning Practice Guidance; giving them a place in the Framework itself puts them on a firmer policy footing.

3. Policy F4 — a Flood Risk Assessment on more sites

This is the change most likely to catch people out. The new wording requires an FRA wherever a site is at risk of flooding from any source, now or in the future — not just where it sits in Flood Zone 2 or 3. In practice that pulls in Flood Zone 1 sites shown at risk of surface water on the Environment Agency's Flood Map for Planning, as well as the familiar over-one-hectare trigger. It is no longer safe to assume that "Zone 1" means "no assessment needed".

4. Policy F5 — the Sequential Test, and a new route for surface-water-only sites

F5 clarifies when the Sequential Test is required and introduces an important route: where a site is at risk solely from surface water, the Sequential Test need not be applied if the FRA demonstrates that occupants will remain safe for the development's lifetime and that flood risk will not be increased elsewhere. Surface water still has to be assessed and managed — the change is about whether the sequential exercise itself is triggered. F5 also confirms that specified householder development, small non-residential extensions and certain changes of use are exempt from the Test.

5. Policies F6 and F7 — the Exception Test and lifetime safety

F6 governs development in Flood Zones 2, 3a and 3b, including when the Exception Test applies and what it must show: wider sustainability benefits that outweigh the risk, safety for the development's lifetime, and no increase in flood risk elsewhere. F7 sets out what "safe" means in practice — placing the more vulnerable parts of a scheme on the lower-risk parts of the site, managing residual risk, providing safe access and escape, and building in resistance and resilience. An FRA that simply states the flood zone will not meet F7; it has to explain what the risk means for this proposal and how it is managed.

6. Policy F8 — SuDS to the National Standards, on all development

F8 is the one developers and their drainage engineers should read twice. Sustainable drainage must now be designed in accordance with the National Standards for Sustainable Drainage Systems (2025), incorporated proportionately to control run-off rates and reduce volumes, and — where possible — deliver water quality, biodiversity and amenity benefits too. Maintenance arrangements must be in place for the lifetime of the development, and LLFA advice must be taken into account on major schemes. F8 also discourages culverting open watercourses without compelling reasons, and encourages restoring culverted channels where that would not increase flood risk. Under the National Standards, expect the upper-end climate change rainfall allowance and an urban creep allowance on impermeable areas to be the norm.

What hasn't changed

It is worth being clear about this, because there is some alarm around. The flood zones on the Flood Map for Planning are unchanged. The Environment Agency's climate change allowance percentages are unchanged — that guidance sits outside the Framework and was last revised in 2022; what has changed is the weight placed on getting them right. The Framework did not bring Schedule 3 of the Flood and Water Management Act into force — that remains a separate matter. And the national SuDS Strategy Templates announced by the Chief Planner on 18 August 2026 are implementation guidance to make submissions consistent, not additional policy.

What it means for you

Homeowners and small projects

If you are extending or converting in Flood Zone 2 or 3 you will still need an FRA, though the Sequential Test will usually not apply to a householder extension. The new wrinkle is surface water: if the Flood Map shows your Zone 1 property at surface water risk, expect the council to ask for an assessment where it previously might not have. A proportionate FRA deals with this quickly.

Developers and landowners

Two practical shifts. First, more sites need an FRA, so build it into feasibility rather than discovering it at validation. Second, SuDS to the National Standards is now the baseline on every scheme — which means allowing space for drainage features early, designing to the upper-end climate allowance, and having a credible maintenance and adoption plan from the outset. Retrofitting drainage into a fixed layout is where schemes lose time and money.

Architects and planning consultants

Update your planning statements and consultant briefs to the new policy codes — F5, F7 and F8 in particular — and check any FRA or drainage strategy already prepared against them. A report written to the December 2024 Framework isn't automatically wrong, but an officer will notice it references superseded policy, and that is an easy reason for a request for further information.

Applications already in the system

Because the new national decision-making policies became material considerations on 17 August 2026, an application submitted before that date but not yet decided may be assessed against them. That does not mean every live application needs a new FRA — but it is worth checking whether the evidence already submitted still answers the questions the new policies ask.

The view from the other side of the desk

When I sat in the LLFA, the applications that sailed through were the ones where the flood and drainage evidence answered the policy tests directly, in order, with numbers. The new Framework makes that easier, because the tests are now explicit and coded. The applications that stalled were the ones that described a site's flood zone and stopped. Under F4, F7 and F8 that approach will stall more often. If you have a scheme in the pipeline, the sensible move is a quick review against the new policies before submission — it is far cheaper than a refusal.

Sources: National Planning Policy Framework (GOV.UK) · National Standards for Sustainable Drainage Systems (GOV.UK). Policy references should always be checked against the current published Framework.

Check your scheme against the new NPPF

All Services & Resources

Everything you need for flood risk, drainage and environmental planning consultancy across England and Wales.