Tuesday, July 24, 2007
Soils and flooding - key research from 1999 not followed up.
The ‘current floods’ referred to in that release were the June Events in the North.“After the severe floods of November 1999” says Dick Thompson, NSRI Director “and with the help of the Environment Agency, we looked at the soils within affected catchments and found many to have poor structure.
“Soils were waterlogged on their surface but dry to five cm depth beneath and were not absorbing the rain falling on them. We recommended further field-based investigation to establish properly the link between field soil conditions and flooding.
"Seven years on”, he continued “a field-based study has yet to be commissioned and damaging floods appear even more frequent."
Soil scientists at NSRI believe that the severity of the weather may only be part of the story.
The majority of rain, probably 90%, falls on open countryside where the soil and
vegetation absorb rainwater before it is discharged slowly to the river network.Flooding occurs when the rainfall exceeds the ability of the land to absorb and retain it. Compact or 'capped' soils have much reduced infiltration capacities and rainfall runs off into the rivers more readily. This sort of uncontrolled run-off is a cause of local flash flooding. It needs to be established in detail whether such effects have contributed to the current floods.
Another NSRI initiative was launched on 18th July. Planning authorities and others concerned about flood risks for specific development sites may be interested in Cranfield’s new ‘Soil Site Reporter’ database and information service,
The Soil Site Reporter is a new, easy-to-use, soil reporting tool which produces site-specific soil information with maps and soil descriptions.
As the national authority on the sustainable management of soil resources for England and Wales, NSRI holds a vast collection of soils information, now available in a matter of minutes with the input of a grid reference or post code.
Each report, downloadable in pdf format, provides detailed information on the expected soil conditions at the site and outlines interpretations of the suitability for different uses. It also details a variety of environmental issues such as the potential of damaging ground movement or pipe corrosion, and the ease with which chemicals can leach into groundwater or runoff into rivers.
Please note I am not in any way connected with Cranfield University still less of NSRI – I only report with local pride something of national impact with clear relevance to very serious developments.
Labels: Cranfield, development control, Floods, Soils