Modelling how water on the surface and below it contributes to floods

This project created and tested models to predict floods from a combination of high water levels below the surface and runoff from near the surface.

• From: Flood and Coastal Erosion Risk Management Research and Development Programme and Department for Environment, Food & Rural Affairs
• Published: 11 February 2021

• Category: Understanding risks from all sources of flooding
• Topics: Flood forecasting, Hydrology, Modelling, Surface water, Understanding physical processes
• Project status: Completed
• Project code: FD0425
• Date of completion: 31 March 2000

Documents

Modelling floods from combined surface and subsurface sources - final report (36.5 KB) WORD

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Details

This research explored methods of modelling floods where water, both above and below the surface, contributes to the flow of the river. It provided a tool to explore flooding from high water levels under the surface and runoff near the surface.

Surface and subsurface water contributes to floods through complex hydrological processes, but the modelling can handle most catchments for the purposes of estimating how often floods might happen. All models explored as part of this project were ‘continuous simulation’ models.

A project database of surface and subsurface hydrology was established to test the models. 21 catchments in southern and eastern England were chosen based on areas with significant occurrence of subsurface water.

The modelling aimed to improve estimates of how often floods might happen to help with planning flood defences.

This project ran from 1997 to 2000 at a cost of £180,000.

Published 11 February 2021