LISFLOODFP

LISFLOOD-FP is a two-dimensional hydrodynamic modelling framework used for simulating flood events in rivers and floodplains. The FP suffix denotes floodplain capabilities. It is part of the LISFLOOD family of models developed by researchers and practitioners to support flood risk assessment and planning.

The model solves the depth-averaged shallow water equations on a grid using a finite-volume or finite-difference scheme, with explicit time stepping. It includes source terms for bed slope, bottom friction (often Manning's n), river channels, and optional rainfall–runoff input or deficit; a wetting–drying algorithm handles expanding and contracting flood extents.

Inputs include high-resolution topography from digital elevation models, river network geometry, roughness coefficients, boundary conditions, and hydrographs. Outputs consist of flood extents, water depths, velocities, and discharge along channels, suitable for generating hazard maps and for scenario analysis. The model can represent complex features such as embankments, bridges, and culverts.

LISFLOOD-FP has been used for national and regional flood risk assessments in multiple countries and is incorporated into academic research and governmental flood planning workflows. It is designed to handle large, real-world domains and supports parallel computation on modern hardware.

Related topics include LISFLOOD (the broader modelling framework), shallow water equations, hydraulic modelling, and flood hazard mapping.