Wales • TAN15 2024 • DAM Zones B, C1 & C2

Flood Consequence Assessments Wales (TAN15)

Expert FCAs under TAN15 (2024) for planning applications across all Welsh LPA areas, satisfying NRW and local planning authority requirements.

TAN15 2024 specialists
All Welsh LPAs
NRW compliant
DAM B, C1 & C2
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Flood Consequence Assessments for Planning in Wales

Planning applications in Wales that fall within Development Advice Map (DAM) zones B, C1 or C2 require a Flood Consequence Assessment (FCA) under Technical Advice Note 15 (TAN15, 2024). An FCA is the Welsh equivalent of a Flood Risk Assessment in England, but follows the specific methodology and policy requirements set out in TAN15 rather than the English NPPF.

We prepare Flood Consequence Assessments for planning applications across all local planning authority areas in Wales, including those in the jurisdiction of Natural Resources Wales (NRW) — the statutory consultee for flood risk in Wales. Our FCAs are written to satisfy TAN15 and the specific requirements of your Welsh LPA.

TAN15 flood risk mapping and Development Advice Map for Wales

The revised TAN15 (2024) introduced significant changes to flood risk policy in Wales, including a new DAM classification system. If you've received conflicting advice about whether TAN15 or the old flood zone system applies to your site, contact us for clarity.

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TAN15 DAM Zones Explained

The 2024 Development Advice Map (DAM) classifies land in Wales into four zones based on flood probability from rivers and the sea.

Flooding in Wales during Storm Callum — TAN15 flood risk areas

DAM A — Low Flood Risk

Land at low risk of flooding from rivers or the sea. No Flood Consequence Assessment is required for development in DAM A. Planning can proceed without flood risk evidence (subject to surface water drainage requirements).

DAM B — Medium Flood Risk

Land with a medium probability of flooding. A Flood Consequence Assessment is required. Most development types are acceptable in DAM B subject to demonstrating the consequences of flooding are acceptable and the development won't increase flood risk elsewhere.

DAM C1 — High Flood Risk

Land at high risk of flooding. A Flood Consequence Assessment is required and development is limited to specific use types. Highly vulnerable development (e.g. residential) is only acceptable in exceptional circumstances. Both flood consequence and justification tests apply.

DAM C2 — High Flood Risk (Functional Floodplain)

The highest flood risk zone — land that regularly floods or is designed to flood. Development is generally restricted to water-compatible uses and essential infrastructure. Most new development is inappropriate in DAM C2.

What's Included in a TAN15 Flood Consequence Assessment

Flood inundation affecting properties in Wales
  • DAM zone classification and flood probability assessment
  • Identification of all flood sources — river, tidal, surface water and groundwater
  • NRW flood map interrogation and data requests
  • Flood depth, velocity and hazard assessment for the design flood event
  • Climate change assessment in accordance with TAN15 and UK Climate Projections
  • TAN15 justification test (DAM C1 and C2) where required
  • Flood consequence assessment for residents, users and the site
  • Finished floor level and threshold recommendations
  • Safe access and egress assessment for all return periods
  • Flood resilience and resistance measures specification
  • Surface water drainage strategy in accordance with SuDS Wales requirements
  • NRW and Welsh LPA-ready FCA report ready for planning submission

Welsh LPA Areas We Cover

We prepare Flood Consequence Assessments for planning applications across all Welsh local planning authorities, including:

North Wales

  • Gwynedd Council
  • Isle of Anglesey County Council
  • Conwy County Borough Council
  • Denbighshire County Council
  • Flintshire County Council
  • Wrexham County Borough Council

Mid & West Wales

  • Ceredigion County Council
  • Powys County Council
  • Pembrokeshire County Council
  • Carmarthenshire County Council
  • Neath Port Talbot County Borough

South Wales

  • Cardiff Council
  • Vale of Glamorgan Council
  • Bridgend County Borough Council
  • Rhondda Cynon Taf CBC
  • Merthyr Tydfil CBC
  • Caerphilly CBC
  • Newport City Council
  • Monmouthshire County Council
  • Blaenau Gwent CBC
  • Torfaen CBC
  • Swansea Council

Frequently Asked Questions

What is a Flood Consequence Assessment in Wales?
A Flood Consequence Assessment (FCA) is the Welsh equivalent of a Flood Risk Assessment in England. It is required under Technical Advice Note 15 (TAN15, 2024) for planning applications in Wales where the development site falls within a Development Advice Map (DAM) zone — specifically DAM B, C1 or C2. The FCA must demonstrate that the consequences of flooding are acceptable and that the development will not increase flood risk elsewhere.
What is TAN15?
Technical Advice Note 15: Development, Flooding and Coastal Erosion (TAN15) is Welsh Government planning guidance that sets out policy for developments in flood risk areas in Wales. The revised TAN15 was published in 2024 and introduced a new DAM classification system replacing the old Zone A/B/C system. TAN15 applies to all planning applications in Wales where flood risk is a material consideration.
What are DAM zones under TAN15 2024?
The 2024 DAM (Development Advice Map) uses four zones: DAM A (low risk, no FCA required), DAM B (medium risk from river or coastal flooding, FCA required), DAM C1 (high risk, limited types of development acceptable, FCA required), and DAM C2 (high risk, functional floodplain, most development inappropriate). The zones broadly correspond to the Environment Agency's Flood Zones in England but use different criteria and flood probability thresholds.
Do I need a Flood Consequence Assessment or a Flood Risk Assessment?
If your development site is in Wales, you need a Flood Consequence Assessment (FCA) under TAN15. If your site is in England, you need a Flood Risk Assessment (FRA) under NPPF. We prepare both FCAs and FRAs, and cover development sites across all of England and Wales.
Do you cover all Welsh LPAs?
Yes — all 22 Welsh local planning authority areas. We also cover NRW consultations and prepare the full FCA documentation required for submission alongside your planning application.

Trusted by Developers, Architects & Planning Consultants

★★★★★

“Antony was great to work with when we needed a Flood Risk Assessment and Emergency Flood Plan. As an architect I would definitely use FRE Consultants again — professional and produced reports within a good time frame.”

Arkhi Architects
Architect, England
★★★★★

“The service received was great and at a competitive cost. We were granted planning after first submission.”

Holly Addison
Homeowner
★★★★★

“Fast, technically thorough and understood exactly what the LLFA needed. Approved without any queries. Highly recommended for any flood risk or drainage work.”

Planning Consultant
East Midlands

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