Flood Consequence Assessments
Important part of the planning process
Flood Consequence Assessments (FCA's) are an important part of the planning process and are mandatory for all new developments in Wales within zone C
areas. These areas are shown on the Welsh Government's development advice map (DAM) and include areas predicted to be at risk of flooding more frequently
than once in 1,000 years. FCA's examine if a proposed development itself will be affected by flooding and also if the development will cause or increase
flooding elsewhere. FCA's are only applicable in Wales, the corresponding document in England is the
Flood Risk Assessment.
The Welsh Government's guidance document, Technical Advice Note 15 (TAN15), sets out the requirement for site specific FCA's. The requirement to
examine the consequences of flooding for up to the 1 in 1,000 year return period (0.1% AEP) is particularly onerous.
Breadth of study
The work required for an FCA depends on the particular site and on the information available from Natural Resources Wales. In some cases, to fulfil
the requirements of TAN15, it may be necessary to use
to assess the flood flows in the watercourse and then to use
1D river modelling
to assess the extent of flooding.
Flow over floodplains or overland flow may also require the use of
2D flood modelling
When carrying out an FCA study we aim to provide a report which is cost effective by making the best use of the existing information and by being
proportionate to the degree of flood risk. At the same time the document should be robust and reliable. For further details please
Areas covered − Our office is in Cardiff so we try to concentrate our FCA work within the south Wales area.
As well as the cities of Cardiff, Swansea and Newport this includes the main towns of Llanelli, Port Talbot, Bridgend, Merthyr Tydfil, Caerphilly, Abergavenny and
Monmouth together with the surrounding areas.
Scope of Report − As part of the FCA we would normally consult with Natural Resources Wales and the
drainage section of the council. Unfortunately this can be a protracted process and is likely to set the timescale for the whole FCA. We feel that this
is important since it allows the FCA to address any objections before planning permission is applied for. This may also save you time and expense later.
The quotation will give our best estimate of the scope of an FCA to cover your needs. During the course of a study, occasionally,
new information may indicate that additional work is called for. In this case we will discuss this with you before incurring extra costs.
Deliverables − We will send a PDF copy of the completed report via e-mail. We do not normally supply a paper
copy of the report.
Copyright − The report will be protected by copyright but we give you permission to produce an unlimited number
Payment − Our quotation will set out the payment terms and we accept payment by cheque or direct transfer via
Quotation − Please
for a free no obligations quotation for a Flood Consequence Assessment (FCA) tailored to your specific site and needs.
This will give the cost, an estimate of how long it would take and detail the scope of the report.