TAN 15 suspension allows for clarification of new policy

The Welsh Government’s 18-month suspension of the revised Technical Advice Note 15 provides an opportunity to clarify this key policy, which has implications for both local planning authorities and developers.

Written by George Baker | Associate Director

Suspension of TAN 15 update

Just weeks after publication of the much-anticipated update to Technical Advice Note 15 (TAN 15), the Welsh Government announced an 18-month suspension of the new policy. To allow local planning authorities time to fully consider the impact of climate change projections.

It is hoped that this delay will allow the Welsh Government time to publish further guidance and issue several clarifications to the policy. In an article for the Royal Institution of Chartered Surveyors (RICS), Associate Director, George Baker shared details of these clarifications – and highlighted areas where more information may still be needed.

Adoption of risk based approach

The new TAN 15 moves away from the precautionary approach taken in the 2004 version, focusing instead on risk-based, plan-led decision making and climate change resilience.

With an estimated 245,000 properties in Wales already vulnerable to flooding, this change in strategy will be critical in limiting the impact of climate change and ensuring the future resilience of development.

To coincide with the publication of the revised TAN 15, a new Flood Map for Planning (FMfP) was published. To fully understand the implications of TAN 15, we need knowledge of the differences between the new FMfP and the Development Advice Map (DAM), which it replaced.

Flood Map for Planning (FMfP) implications

One of the key differences is again the adoption of a more risk-based approach to decision making. Whereas DAM had a single flood risk zone, the FMfP has two flood risk zones. These support the new TAN policy, which reflects different levels of flood risk. The FMfP zones also make allowances for the effects of climate change over the next century.

The other notable change is that the FMfP incorporates flood risk from surface water and small watercourses, in addition to that from rivers and sea. Development proposals will need to include a more comprehensive assessment of flood risk.

Consequences for future development

The new TAN 15 and associated mapping now means that large areas previously designated as being at little or no risk of flooding are now in the highest risk category. In the future, there may be a greater number of instances where flood risk concerns prohibit development and re-development plans. This may have significant implications in some areas for the growth and sustainability of existing communities. Including in some cases, development that could make these communities more resilient to the effects of climate change and flooding.

Whilst the update has clarified some elements of TAN 15, it remains clear that significant change is coming to flood risk and development policy. It is advised that planning and property professionals seek the advice of a flood risk consultant as soon as possible if they find that a site is in a flood zone.

Advice for planning authorities and developers

The updated Welsh Government guidance outlined that for the purpose of revised development plans, planning authorities should be using the new TAN 15. As highlighted in George Baker’s article, the new guidance advises:

  1. Development should be directed away from areas at risk of flooding
  2. A renewed emphasis on preparing Strategic Flood Consequence Assessments (SFCAs) with local authorities expected to prepare these by the end of November 2022
  3. Undeveloped, greenfield floodplains should be safeguarded from development
  4. Development in at-risk areas is only allowed on brownfield land
  5. Some forms of development are more appropriate than others in areas at risk of flood
  6. Development in flood risk areas requires justification tests to be completed
  7. If development is justified in an at-risk location, a Flood Consequences Assessment (FCA) is required to show that flood risk can be safely managed
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Want to know more?

For more information about the updated policy, please get in touch with George Baker.


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