Huge sinkhole in Surrey street

I heard it was built on top of an old quarry. You would have thought people would do their homework but probably more bank handers from developers wanting to build on cheap land and make a massive profit...

I have driven around the diversion today absolute nightmare. I had an appt in the next town . People have been evacuated from the nearest houses and don’t know when they can go back. One guy had only been in his new house a week and now can’t live in it! Terrible for those who live there. A damn nuisance for us who live nearby too

My house builder had to go down over 3 metres to reach solid rock. Many old houses were built without footings and could indeed slide away

That area has a deep chalk layer, covered with a thin clay, studded with flint. Increased CO2 in the atmosphere, mixes with rain and slowly, over 20-30 years, seeps through the clay and erodes the chalk underneath, after a while, the resulting hollow can’t support the weight and it all collapses. Going to be an increasingly common issue. Retired environmental scientist.

We lived in the local area for @ 40 years, in Caterham and Warlingham, just up the road. There is a large network of caves locally, probably where your daughter went, Litterpicker.
The road itself is part of the road network that joins the M25, very busy with heavy vehicles.

Smintie

That area has a deep chalk layer, covered with a thin clay, studded with flint. Increased CO2 in the atmosphere, mixes with rain and slowly, over 20-30 years, seeps through the clay and erodes the chalk underneath, after a while, the resulting hollow can’t support the weight and it all collapses. Going to be an increasingly common issue. Retired environmental scientist.

I remember reading about it, it's rather interesting. I also read about building on old garbage dumps causing similar issues of subsidence.

On the news a minute ago. It’s right next to a lot of new build properties. The tarmac layer of road was very think. All pipes were exposed. It’s going to take weeks apparently while they investigate. It’s a road in constant use, a busy road which leads to the M25. Heavy Lorrie’s thunder up and down every day. It’s a pretty little village but the traffic is heavy.

Tarmac layer very thin. It should have said.

When they were widening the M25 about 10 years ago, roughly between junctions 16-19, north of the river, they were having to put in metal shuttering to contain the cuttings because before they did it, you could see that the chalk of the Chilterns was absolutel riddled with solution holes some 10 feet or more wide and going down up to 30 feet

The solution holes had filled up with sand and gravel over thousans/millions of years and unless the shuttering was there the filling sof these holes would subside and slumo onto the road.

We have sunk into a nation of sinkholes by the looks of it. This was on Sky News tonight.

news.sky.com/story/what-causes-sinkholes-and-why-are-they-popping-up-in-the-uk-13312658

Grandma70s

Doesn’t the Bible have something to say about the foolishness of building a house on sand?

Yes, Grandma, it does! You are a lady after my own heart.

Unfortunately, a lot of people do not read the Bible anymore, and civil servants, including the Planning authorities, if they did ever read it, got no further than "Let not thy left hand know, what the right hand doeth." Or was it the right hand that was to be kept in ignorance?

I presume those quarry caves and mine-workings must be under the M25 also (Godstone being to the South, and Caterham to the North)

Grandma70s

Doesn’t the Bible have something to say about the foolishness of building a house on sand?

Ha - was coming here to say exactly the same!

If you look closely at the video there is a torrent of water running underneath, as thought there is a stream/river under the road. Maybe a bit misleading, but I'm pretty sure its because the houses were built on unsuitable ground rather than fracking as another previous poster said

TopSec

If you look closely at the video there is a torrent of water running underneath, as thought there is a stream/river under the road. Maybe a bit misleading, but I'm pretty sure its because the houses were built on unsuitable ground rather than fracking as another previous poster said

It started with a burst water main.