Flood Risk Assessment
FRAA site-specific assessment of all sources of flood risk to and from a development site, required to support planning applications in areas at risk of flooding.
A Flood Risk Assessment is a technical document prepared by a qualified engineer or flood risk consultant to evaluate the likelihood and consequences of flooding at a proposed development site. FRAs are required under the National Planning Policy Framework (NPPF) for all development proposals in Flood Zones 2 and 3, and for sites larger than one hectare in Flood Zone 1.
The assessment considers all sources of flood risk, including fluvial (river), pluvial (surface water), tidal, groundwater, sewer, and artificial sources such as reservoirs and canals. It evaluates both the risk to the proposed development and any impact the development may have on flood risk elsewhere.
A comprehensive FRA typically includes:
- A review of existing flood risk data from the Environment Agency and Lead Local Flood Authority
- An assessment against the site’s vulnerability classification
- Application of climate change allowances to future flood levels
- Determination of appropriate finished floor levels with freeboard
- Demonstration that the Sequential Test and, where necessary, the Exception Test have been satisfied
- A surface water drainage strategy, often incorporating SuDS
Aegaea delivers flood risk assessments supported by in-house hydraulic modelling capability, ensuring technical rigour and faster turnaround. Our FloodMetric platform provides instant pre-screening to identify constraints before the full assessment begins.