Improving the certainty of flood estimates with new data on towns and cities
This project used new data about urban development to create a new tool (URBEXT2000) for the Flood Estimation Handbook (FEH).
Documents
If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email: defra.helpline@defra.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.
Details
The methods in the Flood Estimation Handbook (FEH) are widely used for estimating flood in the UK. The tools use catchment descriptors, which measure physical and climate-related aspects of the catchment, but these do not take the growth of towns and cities into account. This urbanisation can often have a considerable effect on how floods happen downstream. The new FEH catchment descriptor defining urban extent (URBEXT) provides a way of taking account of this effect.
The land cover data used as the basis for URBEXT during the FEH research programme was based on satellite imagery taken around 1990. The release of the Centre of Ecology and Hydrology Land Cover Map 2000 provided an opportunity to bring this data up to date. The project developed a new index based on the new data (URBEXT2000) and created new FEH procedures based on URBEXT2000.
These important improvements to key elements of the FEH procedures and software will reduce the uncertainty of flood estimates. It’ll also improve industry standard procedures for estimating flood in the UK.
This project ran from 2003 to 2005 at a cost of £74,939.