PPG Change: Flooding and the Sequential Test

In September 2025, the Government updated its Planning Practice Guidance (PPG) on flood risk.

These changes clarify how the Sequential Test — the process for steering new development to the areas of lowest flood risk — should be applied.

For town and parish councillors, this update is especially relevant when reviewing planning applications or shaping a Neighbourhood Plan.

What’s changed in the PPG

1. All Sources of Flooding Count

The Sequential Test must now consider all forms of flood risk, not just rivers or the sea.That includes surface water, groundwater, reservoirs, canals, and drainage systems, as well as future climate change impacts.

2. Limited Exception for Surface Water

If a site-specific Flood Risk Assessment (FRA) proves that people and property will be safe from current and future surface-water flooding for the development’s lifetime, through its layout, design and mitigation measures (i.e, it addresses any risk identified by the Environment Agency mapping) — and there’s no increase in risk elsewhere — the Sequential Test does not have to be applied. However, this applies only to surface water and only when the evidence is clear and robust.

3. A Proportionate ‘Area of Search’

The PPG now says the search area for alternative, lower-risk sites should match the scale and type of development.For small schemes or village infill, the search area should usually be limited to the settlement and its immediate neighbours, not an entire district.

4. Clarifying “Reasonably Available”

Alternative sites count as “reasonably available” if they are:

• Suitable for the proposed use

• Capable of meeting the same need

• Realistically deliverable in the same timeframe. Ownership doesn’t matter, and two or more smaller sites can be combined to meet the same need.

5. Housing Shortfall ≠ Flood Risk Exemption

A lack of five-year housing land supply does not remove the need for the Sequential Test. Flood safety still takes priority.

How can your Council apply this knowledge?

When your council comments on planning applications or develops a Neighbourhood Plan, use the updated guidance to:

✅ Scrutinise Flood Risk Assessments: Make sure they include all flood sources, not just rivers or seas.

✅ Challenge “No Sequential Test Needed” Claims: If developers rely on the surface-water exception, ensure clear evidence on climate change allowances, safe access/egress, and proof that no extra risk is created elsewhere.

✅ Ensure a proportionate search area: The catchment area should always be appropriate to the nature and scale of the proposal and the settlement it is proposed for.

✅ Question Site Dismissals: If alternatives were rejected because they’re not owned by the applicant, remind planners that ownership doesn’t matter under paragraph 28.

✅ Strengthen Neighbourhood Plans: Apply the all-sources approach to site selection and record your reasoning clearly — this will help your Plan withstand scrutiny at examination.