Development of estuary morphology models

Flood risk management in estuaries needs well-validated models to predict morphology. The UK Estuaries Research Programme (ERP) addresses the challenge of predicting longer-term morphological changes. Project FD2107 in ERP aimed to enhance “Hybrid” models combining elements and advantages of “top-down” and process-based “bottom-up” approaches. Developments include:
- an Analytical Emulator based on 1-D hydrodynamics;
- a Hybrid Regime model combining 1-D hydrodynamics, regime relations and evolving cross-sections;
- Morpho-SandTrack: 2-D hydrodynamics, sediment dynamics and particle-tracking to change morphology;
- a Realignment model with 2-D flow and waves to spread sediment and predict local changes;
- ASMITA (pre-existing) now in Matlab, evolving the size of aggregated intertidal areas and channels;
- an inverse model evolving depth in 2-D by a diffusion equation plus “source” based on past changes.

Applications to eight varied UK estuaries and different scenarios identified impacts, sensitivities, respective merits of the models and good practice for morphological predictions.