Future-Proofing Planning Applications: How Flood Risk Policy Is Likely to Evolve

Flood risk planning policy in England has never been static. However, over recent years there have been many changes to how national planning policy addresses climate change, surface water flooding and the long-term resilience of new development. For architects and planning consultants, understanding the direction of travel is becoming just as important as understanding current requirements.

The recent consultation on a revised National Planning Policy Framework (NPPF), draft text published in December 2025, provides a valuable insight into how flood risk and drainage policy may continue to tighten. While consultation drafts do not carry policy weight, they signal future expectations that local planning authorities, Lead Local Flood Authorities and statutory consultees may begin to apply in practice before formal adoption.

This article explores what future updates to flood risk policy are likely to focus on, what this could mean for Flood Risk Assessments and surface water drainage design, and why early, policy-aligned advice is increasingly critical to reducing planning risk.

Evolving Policy Context

The current NPPF already requires development to be steered away from areas at highest risk of flooding through the Sequential Test, and where necessary, the Exception Test. It also places a clear emphasis on ensuring that development is safe for its lifetime, without increasing flood risk elsewhere, and where possible, reduces overall flood risk.

The December 2025 NPPF consultation document builds on this foundation, with stronger language around climate resilience, surface water management and adaptation to future flood risk. While detailed wording may change before adoption, several themes are consistent with other recently published government guidance.

In general, there is a growing emphasis on climate change allowances being treated as a baseline rather than a sensitivity test. The Environment Agency’s climate change allowances for flood risk assessments have been in place for several years. However, the NPPF consultation (along with other recent planning guidance) signals that accounting for upper-end allowances will become an expectation for certain development types, particularly where land use vulnerability is high or the consequences of failure are significant.

Surface water flooding is also more explicitly recognised as a planning issue. The consultation aligns with existing Planning Practice Guidance, which already highlights surface water as a major source of flood risk nationally, particularly in urban areas. This reinforces the role of sustainable urban drainage systems as an essential element within development proposals rather than an optional design feature.

A common theme through the NPPF consultation document is greater emphasis on site-specific flood risk assessments and surface water drainage strategies being proportionate to the scale, nature, and location of a development.

What Tighter Policy Could Mean For Flood Risk Assessments

As policy evolves, Flood Risk Assessments are likely to be scrutinised more closely for both technical robustness and policy alignment. A compliant FRA will increasingly need to demonstrate not just that risks have been identified, but that a development is safe for its lifetime without increasing flood risk elsewhere.

Key areas of focus are likely to include clearer justification of site selection in relation to flood risk from all sources, more detailed assessment of escape routes, greater consideration of surface water risk, and stronger evidence that mitigation measures will remain effective over the lifetime of a development.

Sequential and Exception Test reporting is also likely to become more of a common requirement with Planning Officers likely to expect a transparent narrative explaining why a site is appropriate in flood risk terms, particularly for major or sensitive developments.

It will become increasingly important to understand the risk of flooding at, and surrounding, a site from project inception so that any risks can be managed appropriately within effective development design.

FRAs that are prepared late in the design process often struggle to influence layout, levels and land use distribution. As expectations rise, this reactive approach will increase the risk of objection, redesign and delay.

Implications For SuDS and Surface Water Drainage Strategies

The direction of policy also points towards more ambitious expectations for sustainable drainage. National standards already require peak flow control and appropriate volume management, but emerging policy language places greater emphasis on multifunctional SuDS that deliver wider benefits.

Drainage strategies for all development types are increasingly expected to demonstrate how surface water runoff is managed for exceedance events, how flows are routed safely during extreme rainfall, and how systems will be maintained over the long term. Climate change allowances are likely to be applied more consistently, reducing the scope for under-designed systems.

The CIRIA SuDS Manual remains the primary technical reference, but local interpretation by LLFAs is becoming more aligned with national policy objectives. Early understanding of local requirements, combined with a strong policy narrative, can significantly improve the prospects of approval.

Reducing Planning Risk Through Early, Policy-Aligned Advice

One of the clearest messages from evolving flood risk policy is the value of early engagement. Aligning site appraisal, development layout and drainage design with both current and emerging policy expectations can materially reduce planning risk.

For architects and planning consultants, this means treating flood risk and drainage as formative design inputs rather than validation exercises. Early advice allows constraints to be identified before they become a problem and enables a clear policy narrative to be developed alongside the design.

As national planning policy continues to evolve, schemes that demonstrate foresight, resilience and alignment with the direction of travel are more likely to progress smoothly through the planning process.

If you have a project and would like any flood risk or drainage advice to help future-proof your planning application, please contact info@geoson.co.uk or call us on 01174 414993.