What is flood modelling?

Flood modelling is the use of specialized computer software to simulate how water moves across a landscape during extreme weather events. In the UK planning context, it is used to provide the technical evidence required for a Flood Risk Assessment (FRA), especially when official Environment Agency maps lack the detail needed for a specific site.

How it is utilized

1D Modeling: This represents the river or stream within which a developer is proposing to build. The goal of the 1D modeling is to determine the water level and flow rate.

2D Modeling: This uses a digital terrain model to illustrate where floodwater will spread over the land, as well as determine flood depths and velocities at specific areas of buildings.

Why it is needed

Standard flood maps can be very general. The customization of modeling allows developers to test mitigation options such as testing whether raising finished floor levels will create an additional threats.