Advanced Solvers

Developed for nearly 50 years, Flood Modeller’s solvers are some of the fastest and most robust solutions available. It makes them an ideal choice for a wide range of applications, from site specific studies to modelling entire catchments or countries.

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Open channel modelling (1D)

Our industry-leading 1D river solvers allows you to simulate flows and levels in open channels, floodplains, reservoirs, and estuaries. They are capable of modelling subcritical, supercritical, and transitional flow regimes, they can be confidently applied to a wide range of applications, from steep river flows to tidally influenced estuaries. Find out more

Urban drainage and stormwater modelling (1D)

Our 1D urban solver allows you to confidently model drainage and sewer systems to assess extreme events. You can also combine surface and sub-surface flow to obtain a detailed and integrated understanding of flood risk in urban areas and develop integrated catchment-based solutions. Find out more

Overland, surface water and direct rainfall modelling (2D)

Flood Modeller provides four powerful CPU and GPU enabled 2D solvers which have been specifically designed to accurately undertake local and catchment scale modelling, surface water analysis, flood mapping, embankment and asset failure assessments, and a wide range of other applications. Find out more

Integrated modelling (1D/2D)

All our solvers can be dynamically linked to simulate integrated models where multiple sources of flooding are present. 

Modelling river systems, surface water or urban drainage networks separately can provide important insights but can often make it very difficult to represent the combined flood risk accurately. 

With Flood Modeller, you can use the 1D river solver to model river channels, or its 2D solver to model surface water flow, whilst linking to the 1D urban solver to model the interaction with and the impact on the drainage network. It allows for a better understanding of flood risk and enhances decision-making.

Water quality modelling (1D)

The 1D water quality solver simulates advection/diffusion of conservative and decaying pollutants, water temperature, cohesive sediment transport, interaction of quality determinands with sediments, phytoplankton and pH.

It can be used in conjunction with a full hydrodynamic simulation to simulate water quality processes in detail or can be driven by Flood Modeller’s hydrological routing results for less detailed applications.

It solves the 1D advection-diffusion equation and any biochemical equations required. 


Model boundaries are represented by concentration-time or concentration-flow relationships. Pollutants can also be introduced at or removed from any point in the model.

Sediment transport modelling (1D)

The 1D sediment transport solver predicts the sediment transport rates and patterns of erosion/deposition in river channels. It has been applied to many natural and engineered channels and has been used to study sedimentation problems for both uniform and graded sediments.

It includes six sediment transport equations and can predict sediment transport rates, bed elevations and amounts of erosion or deposition throughout a channel system. This is achieved by using the Flood Modeller’s 1D solver to calculate the hydraulic variables of flow, stage, velocity at each timestep.

Various options are provided within the solver, including specification of dredging, cohesive sediment transport and rigid beds.