What is a sinkhole and are they caused by bad weather?

By Emma Bowden, PA

A sinkhole has opened up on a residential road in Essex after Storm Ciara swept across the UK with strong gales and heavy downpours.

A motorist had a lucky escape when his Toyata car fell into a huge sinkhole on Hatch Road in Brentwood, which led to the evacuation of six properties in the early hours of Monday morning.

The wild weather also saw a huge sinkhole open up in a garden in Belfield, Rochdale.

What is a sinkhole?

A sinkhole, sometimes called a doline, is a hole in the ground usually formed when water dissolves an underlying layer of rock.

As the rock dissolves, spaces develop underground, causing the land on the surface to collapse into the hole underneath.

Some sinkholes are created slowly, while others can suddenly appear.

The later is referred to as a “drop out” sinkhole, according to the British Geological Survey (BGS), which they refer to as the “more spectacular collapses”.

They have both natural and human causes and can vary in width and depth, ranging from a slight depression to a huge hole – swallowing parts of roads, or even buildings.

What can trigger a sinkhole?

(PA Graphics)

Sinkholes can form following heavy rain or surface flooding, BGS said.

This is because these factors can cause an increase in erosion underground, as well as weakening the land above.

But they can also be triggered by leaking drain pipes, burst water mains or irrigation, while construction works and mining can also be a factor.

The BGS said areas that are prone to sinkholes include parts of Wales, the Peak District and the northern Pennines including the Yorkshire Dales.

One of the UK’s most sinkhole-prone areas is Ripon, a city in North Yorkshire, because it sits on a layer of “gypsum” – a water-soluble rock.