Photograph - Flooding at Fleet Lane, Bredon. December 2012

Flooding at Fleet Lane, Bredon. December 2012.

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 FEH methods 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 techniques.

Cost Effective

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 contact us.

Further Details

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 of copies.

Payment − Our quotation will set out the payment terms and we accept payment by cheque or direct transfer via Internet banking.

Quotation − Please contact us 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.


Drainage for New Developments

Expert Witness

Flood Risk Assessments

Flood Consequence Assessments


River Modelling

About Morton-Roberts

Recent Projects

Contact Us for Further Details