Flood Map for Planning / Development Advice Map

Development Advice Map

The Development Advice Map and associated planning policy TAN15: Development and Flood Risk is the current framework for assessing flood risk to and from new development.  

The Development Advice Map is used as a screening tool by Local Authorities to understand where further assessment of flooding may be needed.

(Right click on the map button to open it in a new tab)

 

Flood Map for Planning

A revised TAN15 is due to be implemented in June 2023. This will be supported by the new Flood Map for Planning, which includes climate change information to show how this will affect flood risk extents over the next century. It shows the potential extent of flooding assuming no defences are in place.

The Flood Map for Planning has no official status for planning purposes until June 2023. However local authorities must review their Strategic Flood Consequence Assessments by November 2022 in line with the new TAN15 and Flood Map for Planning.

Natural Resources Wales may also use the Flood Map for Planning data as the ‘best available information’ on flood risk to inform our planning advice.

More information on the formal implementation of the new TAN15 and Flood Map for Planning is set out in the Written Statement from the Welsh Government

The Flood Map for Planning has two views: 

• Basic - this includes enough data for high level screening against TAN 15
• Detailed - this includes extra detail that can be used for Flood Consequences Assessments

(Right click on the map button to open it in a new tab)

 

For present day, defended flood risk, view our Flood Risk Assessment Wales map. This map has no official status for planning purposes, as it does not consider the impact of climate change in the future. Together the two maps form the Wales Flood Map. 

What do the map layers mean? 

The Flood Map for Planning has the following layers, which show the potential extent of flooding, assuming no defences are in place:

Rivers – Flood Zone 2

Areas with 0.1% to 1% (1 in 1000 to 1 in 100) chance of flooding from rivers in a given year, including the effects of climate change. 

Rivers – Flood Zone 3

Areas with more than 1% (1 in 100) chance of flooding from rivers in a given year, including the effects of climate change. 

Rivers & Sea – Flood Zone 2

The combined 0.1% risk of flooding from rivers and the sea including climate change.

Rivers & Sea – Flood Zone 3

The combined 1% risk of flooding from rivers and the sea including climate change.

Sea – Flood Zone 2

Areas with 0.1% to 0.5% (1 in 1000 to 1 in 200) chance of flooding from the sea in a given year, including the effects of climate change.

Sea – Flood Zone 3

Surface Water and Small Watercourses – Flood Zone 2

Areas with 0.1% to 1% (1 in 1000 to 1 in 100) chance of flooding from surface water and/or small watercourses in a given year, including the effects of climate change.

Surface Water and Small Watercourses – Flood Zone 3

Areas with more than 1% (1 in 100) chance of flooding from surface water and/or small watercourses in a given year, including the effects of climate change

TAN15 Defended Zones

Area that benefit from Risk Management Authority flood defences with the following minimum Standard of Protection:

• 1 in 100 year (present day) for rivers
• 1 in 200 year (present day) for the sea

For flood defences built from 2016 onwards there must be allowance for climate change and design freeboard. 

Recorded Flood Extents

Areas that are recorded as having flooded previously.

Flood defence location

More information about the location and standard of protection of formal flood risk defences.

Flood risk from reservoirs

More information about reservoir flood risk.

Main rivers

More information about main rivers. If a planning proposal is next to a main river, you may need a permit in addition to planning permission. 

NRW Local Model Manager

Areas where NRW holds detailed local flood models, which may be useful to help inform a flood consequences assessment to support a planning application. Contact datadistribution@naturalresourceswales.gov.uk to ask for access to this data. 

Shoreline Management Plans & coastal erosion

More information about Shoreline Management Plans and coastal erosion. You will need to consider these plans for coastal development proposals. Erosion rates on the map are for short, medium and longer term periods. These are based on ‘confidence bandings’ (of 5%, 50% and 95%) and follow the current Shoreline Management Plan policies.

Challenging our flood maps 

Find out more about our flood risk mapping information, including guidance about:

Challenging our flood maps

Developing your own hydraulic models

Modelling for Flood Consequence Assessments

Map updates

We update the Flood Map for Planning on behalf of the Welsh Government every year in:

• late May
• late November

We list these updates below but only include changes to: 

• Rivers Flood Zones
• Sea Flood Zones
• Rivers and Sea Flood Zones
• TAN15 Defended Zones  

Contact us about about updates to other layers in the areas below.

May 2022 update

Published 30 May 2022.

PDF Map books show the detail of the changes. These maps show the difference in flood extents between the March 2022 and May 2022 publication. 

Updates to TAN15 Defended Zones:

1. A new Sea TAN15 Defended Zone was created for Aberaeron.
2. A Sea TAN15 Defended Zone was removed at Marshes, Newport.

Updates to Rivers Flood Zones:

1. River Daron at Aberdaron
2. River Cresswell at Begelly
3. River Hoddnant at Boverton
4. River Wye at Builth Wells
5. River Towy at Carmarthen
6. Nant y Glasdwr at Cwmffrwd
7. River Giedd at Cwmgiedd
8. River Tawe at Cwmtwrch
9. River Rhythalit at Cwm Y Glo
10. River Aman at Glanamman
11. River Western Cleddau at Haverfordwest
12. River Ganol at Llandudno Junction
13. River Towy at Llandeilo
14. River Llanfairfechan at Llanfairfechan
15. River Ceunant at Llanfihangel y Creuddyn
16. River Morlais at Llangennech
17. River Dulais at Llanwrda
18. River Dovey at Machynlleth
19. Melincourt Brook at Melincourt
20. River Pennal at Pennal
21. River Solva at Solva
22. River Aeron at Tal Sarn
23. Lledan Brook at Welshpool
24. River Taf at Whitland

March 2022 Update

Published 17 March 2022. This was a delayed publication from November 2021.

Updates to TAN15 Defended Zones:

1. A River TAN15 Defended Zone was removed at Llangennech
2. A River TAN15 Defended Zone was removed at Ponthir
3. A Sea TAN15 Defended Zone was created at Crofty

Updates to Rivers Flood Zones:

1. River Adda at Bangor on Dee
2. River Cadnant at Caernarfon
3. River Severn at Caersws
4. River Dee at Corwen
5. River Wnion at Dolgellau
6. River Henddol at Fairbourne
7. River Cegidog at Ffrith
8. River Cegidog at Llandrillo
9. River Lliw at Llanuwchllyn
10. River Rheidol at Aberystwyth
11. River Loughor at Ammanford
12. Nant Dyfatty at Burry Port
13. River Cadoxton at Cadoxton
14. Morlais River at Crofty
15. River Towy at Llandovery
16. River Teifi at Llandysul Pentre Cwrt
17. River Rhymney at Llanederyn
18. River Usk at Llanfoist
19. River Llwyd at Pontypool, Cwmbran and Ponthir
20. Ogwr Fawr at Ogmore Vale
21. River Ewenny at Pencoed
22. River Tawe at Pontardawe
23. River Dutlais at Pontardulais
24. River Avan at Port Talbort
25. River Cynffig at Pyle
26. River Neath at Resolven
27. River Cynin at St Clears
28. Rivers Ely and Taff at Cardiff
29. River Rhymney at Ystrad Mynach
30. Pant Basin at Merthyr Tydfil
31. River Alyn at Rhydymwyn

GIS data

If you need to download GIS data, many of the map layers can be downloaded from DataMapWales.

Acknowledgements

Contains Natural Resources Wales information © Natural Resources Wales and database right. All rights reserved. Some features of this information are based on digital spatial data licensed from the UK Centre for Ecology & Hydrology © UKCEH, the Environment Agency © EA and Getmapping Plc and Bluesky International Limited [2015]. Defra, Met Office and DARD Rivers Agency © Crown copyright. © Cranfield University. © James Hutton Institute. Contains OS data © Crown copyright and database right. Land & Property Services © Crown copyright and database r