Sequential Test Failed, Appeal Allowed: What Yatton Means for Planning

What makes this decision especially noteworthy is the Inspector's detailed and critical engagement with both the Sequential Test and Exception Test under national policy, and the nuanced conclusions reached in the context of significant housing shortfall and site-specific flood risk conditions.

The Sequential Test: Not Always Fatal

One of the most striking aspects of the ruling is the Inspector's treatment of the Sequential Test. It was accepted that the proposal did not pass the Sequential Test, even in the context of an allocated site. However, the Inspector took guidance from the Mead judgment ([2024] EWHC 279), which established that failure to comply with the Sequential Test is not necessarily fatal to an application.

The Mead decision clarified that paragraph 162 of the NPPF is deliberately broad, requiring decision-makers to exercise judgement in identifying what constitutes "reasonably available" and "appropriate" alternative sites. It also confirmed that general housing shortfalls are not, in themselves, a reason to bypass the Sequential Test — but that where there is a specific, evidenced need for a particular form or timing of development, this may legitimately influence the assessment.

Crucially, Mead emphasised that the NPPF is not a rulebook. As Mr Justice Holgate stated:

The judgement made clear that failure to apply the Sequential Test in a textbook manner does not automatically equate to unlawful decision-making, provided that the overall planning balance has been properly considered.

In the Yatton appeal, the Inspector acknowledged the failure of the Sequential Test but emphasised that it did not, in itself, justify a refusal. The Inspector considered that a rigid application of the test, in the face of urgent housing need and the site’s relatively low flood hazard (with a long lead time to flood onset), would be disproportionate. This aligns with the principle from Mead that flood risk policy should be applied with flexibility and discretion, especially where other material considerations weigh heavily in favour of development.

The Exception Test: Robust and Site-Specific

Turning to the Exception Test, the Inspector found that both limbs were satisfied. The scheme was judged to offer clear sustainability benefits that outweighed the flood risk, including the delivery of up to 190 much-needed homes in an area facing a significant housing shortfall.

Importantly, the Inspector was satisfied that the development could be made safe for its lifetime. While the access road was at risk of flooding, the proposed homes themselves were not. The flood modelling also demonstrated that it would take approximately 42 hours from first high tide to flooding during a 1 in 200 year post-2080 design storm event. Additionally, the scheme would not increase flood risk elsewhere, and the site was not considered at risk of sudden inundation.

The Inspector gave weight to the design approach, which included elevated finished floor levels, attenuation measures, and a strategy for safe access and egress during flood events. Emergency services confirmed they could reach the site if necessary. These elements demonstrated a proactive and informed response to site-specific flood risk.

This careful consideration of flood dynamics and the mitigation measures proposed ultimately tipped the balance in favour of granting permission, reflecting the pragmatic policy interpretation encouraged in Mead.

Implications for Planning Practice

This decision sends a clear message to developers, local authorities, and planning consultants: flood risk policy, while robust, is not absolute.

For practitioners, there are a few key takeaways:

• The Sequential Test remains a vital part of the decision-making framework, but failure to pass it does not automatically preclude development.
• The Mead judgment continues to shape how Inspectors interpret flood risk policies in the context of housing need and site specifics. It supports a flexible, case-by-case assessment rather than an inflexible rule-based approach.
• Exception Tests must be underpinned by robust, evidence-based assessments that clearly demonstrate safety and no off-site harm.
• The deliverability of sustainable development in areas of flood risk will be increasingly scrutinised on a case-by-case basis, particularly as climate data and housing pressures evolve.
• Planning Practice Guidance (PPG) should not be treated as overriding the NPPF, but rather as supplementary — the Mead ruling confirmed the need for flexibility and realism in applying both.

At Unda, we regularly assist clients in navigating the complexities of flood risk planning policy, from Sequential Test to in-depth FRA preparation. This appeal decision reinforces the value of early and thorough flood risk analysis in the planning process — and the need to understand the policy not as a barrier, but as a framework for informed and resilient development.