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UK 'set to see more sinkholes' as climate change leads to drier summers and wetter winters

A 30ft-deep sinkhole opened up High Wycombe. Photo: Steve Parsons/PA Wire

Sinkholes like those that have recently opened in Ripon, High Wycombe and the Peak District will become more frequent due to the effects of climate change, a leading academic has said.

Natural sinkholes are caused as softer soluble rock and sand is washed away by water.

In some areas vertical gaps in the limestone bedrock have become filled with sand and soil over thousands of years., when this is removed by water sinkholes open up.

The recent increase in the number of sinkholes is due to the severely wet winter which has raised the water table, meaning more is washed away causing instability.

A sinkhole also opened up in the central reservation of the M2 in Kent. Credit: Highways Agency

The wetter winters predicted by climate change will see changes in the water table that could cause more sinkholes, according to Dr Nigel Woodcock from the Department of Earth Sciences at Cambridge University.

Sinkholes can also be caused by the erosion of layers of salt in the ground, which is what Dr Woodcock believes may have caused the Ripon sinkhole.

Watch the British Geological Survey explanation of how these sinkholes happen:

As well as becoming more commonplace in the future, in the shorter term Dr Vanessa Banks from the British Geological Survey (BGS) says we should expect more sinkholes as the ground remains saturated.

The ground is saturated at the moment, in certain parts of the country, and where it's saturated, it will remain saturated for some weeks, if not months.

And gradually the situation will improve, but in the short term I suspect there will be more of these incidents being reported.

– Dr Vanessa Banks, British Geological Survey
The house over a sinkhole in Ripon. Credit: Anna Gowthorpe/PA Wire

Dr Woodcock has called for greater regulation of developers to help stop homes being built on sinkholes.

In lots of cases developers should be required, more than they currently are, to take into account the local geography.

We know where the limestone areas are, detecting sinkholes is costly but developers should be required to do it.

Where areas of instability are identified before building steps can be taken to patch the ground and strengthen it to stop possible sinkholes opening up.

Areas of limestone that are likely to see sinkholes. Credit: British Geological Survey

Most natural sinkholes, those caused by erosion and not old mine shafts or wells, do not usually tend to spread sideways after the initial fall.

However, as mines fall in whole galleries can become weakened and the holes can spread.

Once a sinkhole has opened it can be filled in again, however this can be an expensive process. This is usually done by simply filling the hole in with concrete, although it could take as many as 50 concrete trucks to carry enough to fill an average hole completely.

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