All change for development and flood risk policy in Wales

Today the Welsh Government released their much anticipated update to planning policy advice for development and flood risk in Wales (TAN 15).

The new policy will come into effect on from the 1st December 2021, after which all planning determinations will have to be made on the basis of the new TAN 15 and the new Flood Map for Planning (FMfP).

TAN 15 provides planning advice that informs local development plans and decisions on planning applications in areas at risk of flooding and coastal erosion. It will be used by the Welsh Government, local planning authorities and developers to direct development away from areas at risk of flooding and coastal erosion.

The previous version of TAN 15 was ground breaking when it was first published in 2004. Wales was the first UK nation to introduce flood zones to guide planning decisions. However, since JBA undertook an independent review of TAN 15 in 2018 it has become increasingly apparent that TAN 15 needed a comprehensive update to reflect our current understanding of flood risk, climate change and sustainable development. Not least because of the massive improvements in flood modelling data, such as JBA’s work on Flood Risk Assessment Wales.

Consideration of climate change has always been part of TAN 15, but there have been loopholes in how this was handled. The new TAN 15 corrects this through the development of the UK’s first national flood map that includes allowances for climate change. Additionally, for the first time the Flood Map for Planning includes consideration not just river and sea flooding, but flooding from surface water and small watercourses.

TAN 15 is clear that new developments of homes, emergency services, schools and hospitals and other highly vulnerable land uses, must not be located in areas of high flood risk without strong flood defences. For all development in areas of low risk and areas protected by strong flood defences, and for less vulnerable developments in areas at high risk of flooding, securing planning permission will be dependent on passing the acceptability tests in TAN15. These tests include providing justification for the location in a flood risk area, being on brownfield land and being resilient in the event of a flood.

TAN 15 is also clear that constructing new engineered defences to enable greenfield development is not an appropriate nor a sustainable approach to addressing flood risk.

‘JBA have been a keen and active consultee in the development of the new TAN 15. We welcome a great many of the changes, particularly the clarity around climate change and the adoption of a risk based and plan led approach. However, the devil is in the detail, so we hope that Welsh Government and Natural Resources Wales will remain engaged in improving guidance and working with the development sector to achieve the goals of safe and sustainable development in Wales.’       

George Baker, Associate Director, JBA Consulting

The new TAN 15 is also accompanied by new guidance on climate change. This new guidance includes a new section on rainfall intensity and revisions to sea level rise allowances based on the most up to date assessment of how climate may change in the UK over the 21st Century as presented by UK Climate Projections (UKCP18). Although these changes are generally modest, this latest science for sea level rise is not yet captured in the new Flood Map for Planning. This goes to illustrate our ever changing understanding of flood risk and climate. Such changes will be handled by twice yearly updates to the Flood Map for Planning and a process of Flood Map Challenge. The Flood Map Challenge process is a formal process to submit and agree updates to the flood map based on newer and more detailed flood modelling work.

Want to know more?

If you need help navigating development and flood risk policy in Wales, please get in touch with George Baker.



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