Upgrade to Chrome Upgrade to Firefox Upgrade to Internet Explorer Upgrade to Safari
7th January 2022

TAN 15: The new climate change policy for developers

Future developments in Wales will have to consider flooding and coastal erosion risk caused by climate change during planning in a UK first policy due to be implemented by the Welsh Government.

What is the policy?

The new planning policy advice is known as Technical Advice Note 15 (TAN 15). It will inform future development plans and decisions on planning applications in areas at risk of flooding or coastal erosion.

Developers will now have to work with flood risk and coastal erosion maps that show current risk levels and predict the future risk posed by climate change.

These maps will be consulted by the Welsh Government and local planning authorities at the planning application stage to direct developments away from areas at risk of flooding or coastal erosion in the future.

The Flood Map for Planning is published by Natural Resources Wales and will be updated in May and November every year to reflect the latest modelling and data on flood risks.

When does it come into force?

The current Flood Map for Planning is available now so developers and planning authorities can prepare ahead of the policy coming into effect.

When TAN 15 is implemented, Natural Resources Wales will host the new Flood Map for Planning which will include climate change information to show how this will affect flood risks over the next century and the potential extent of flooding if no defences are in place.

Originally due to start on December 1 2021, the new TAN 15 planning rules have been suspended by the Welsh Government and will not be implemented until June 1 2023.

The suspension will provide Local Authorities with ample time to review the Strategic Flood Consequences Assessments for their respective areas and develop a more detailed understanding of the consequences of flooding.

Why is TAN 15 being introduced?

Climate change is seriously affecting the world, and we’re seeing the results of it in Wales as flood risk and coastal erosion is continually increasing. Across Wales, over 245,000 properties are at risk of flooding from rivers, the sea and surface water and almost 400 properties are also at risk from coastal erosion. Serious floods are becoming more frequent and communities are suffering as a result.

TAN 15 allows developers to see which areas will be prone to flooding in the future as a result of climate change, so they can avoid developing these areas and therefore prevent any damage to communities.

What does it mean for developers?

The responsibility is being passed to developers who must weigh up the risk using the maps and include any necessary additions to ensure planning approval.

TAN 15 is clear that new developments of homes, emergency services, schools and hospitals must not be located in areas of high flood risk without strong flood defences. If a local planning authority approves any scheme against this advice, the Welsh Government is able to decide the application directly.

From June 1 2023, all planning applications awaiting a decision, and all new planning applications, will be assessed against the new advice and map.

Where do I go for more information?

You can visit Natural Resources Wales to view the current Flood Map for Planning and other useful tools for flood risk management.

Our Partners


Subscribe to our mailing list to get a monthly update and to find out news that matters to you.

  • This field is for validation purposes and should be left unchanged.