What survey do I need for a flood risk assessment?

A flood risk assessment typically requires a topographic survey of the site and its surrounding area — capturing ground levels, contours, drainage features, watercourses, culverts, flood plain extents and all features relevant to surface water flow. For sites adjacent to or including watercourses, a bathymetric survey capturing riverbed levels, channel cross-sections and flow profiles may also be required. The level of detail depends on the type of FRA — a Level 1 screening assessment requires less survey data than a Level 2 or Level 3 detailed assessment. We advise on the right survey scope for the FRA type at the time of enquiry.