May 2007

July 2007 | home thanetonline.com michaelsbookshop.com Click here for books about The Isle of Thanet Dangerous cliff ?

this link takes you to the rest of my Pleasurama site this link takes you to my previous correspondence

My attempts learn about the Pleasurama project have lead me into a dialogue with Thanet District Council about their website and the way they pass on correspondence to councillors. Click on the links above to read the correspondence.

May 2007

During my ongoing dialogue about the Pleasurama development one aspect has been my concern about the safety of pile driving next to the cliff, it has become necessary to make my point more clearly to those involved.

There are two areas that I am concerned about, the first being the voids next to Welling ton Crescent the largest being Wellington Caves which are very big stretching back at least to the road. The only collapse that I have been able to obtain photographs of is that on the West cliff in 1947, the cave there was much smaller than Wellington caves but the pictures ckick here give you some idea of what happens when one of these old caves collapses.

The other area that I am concerned about is the other side of the lift where the cliff wall has split and looks to be moving out from the cliff the only pictures of this type of collapse I have managed to find so far is when the cliff wall collapsed at Pegwell in 1947 click here fortunately there weren't any houses in front of it like there are in Ramsgate. You can see that a collapse of this sort could have a considerable impact on Kent Terrace.

If any of you who could provide pictures of some of the other Ramsgate cliff collapses it would be helpful in getting the point across.

There is a dialogue about this going on Cllr Dr Simon Moors Thanet Life Blog should any of you wish to comment, you can even do so anonymously click here.

Courtesy of the Margate Museum

In a message dated 09/05/2007 11:51:49 GMT Standard Time, AGreg115 writes:

Michael,

The two collapses that you show pictures of are not due to the presence of caves,(in fact caves actually help to prevent the collapses you show).

They are collapses due to water seepage from inadequate drainage at the top.

Rainwater ingresses the top of the chalk (rainwater is in reality a mild form of carbonic acid) , and gradually eats away at the chalk, causing weaknesses that result in spectacular collapses. The collapse at Fan Bay near Dover, was the biggest I have seen.(C 1994).

Caves help the situation as they drain the rainfall away naturally.

Ken

Ken thanks for your prompt and helpful reply, I too have read quite a bit about this subject. It looks like the area behind the site has had serious problems with water seepage see seismic survey http://www.michaelsbookshop.com/Survey/ it would seem the chalk is in a pretty bad way. The problem mostly relates to where cliff top areas are concrete or tarmac surfaces, when cracks form in the surface much more water goes through the crack causing the chalk under it to be damaged and the washed away. This eventually causes water channels to the ceiling of the cave below a honeycomb effect. Where the ground above a cave is porous and the chalk is in good condition a ventilated cave below is of benefit keeping the chalk dryer than it would otherwise have been. My knowledge of Wellington caves is fairly sketchy based mostly on the borough surveyor’s map for 1939 the cliff where they are is about 17 meters high and I think the caves are at the bottom suggesting that there is about 14 meters of chalk that is probably fairly damaged above them. If a collapse occurs it will be interesting to see how much of the crescent comes down.

The area behind Kent terrace is showing signs of instability caused by water seepage the concrete cliff wall is cracked and part of it has moved away from the cliff face. The backs of the houses are next to the damaged cliff face.

I am told that the intention is to pile drive first and repair what collapses afterwards, I think independent reports from a geologist and a civil engineer could be worth considering, as being much cheaper for ratepayers in the event of litigation following a possible collapse, it would be better if the experts paid the bill rather than us.

At the moment it seems that TDC is saying to the developer it’s safe but not telling me what this assumption is based on. Of course if you can send me a copy of a letters from qualified experts saying that it is indeed safe I will stop making any fuss about this aspect of the development.

I have as I said put up our correspondence at http://www.michaelsbookshop.com/tdc/id35.htm Michael

In a message dated 09/05/2007 13:15:40 GMT Standard Time, lauraprobert@btinternet.com writes:

Brilliant research - just shows you we can't take anything for granted - my hope is that the first burst of the pile driver will set off a collapse like that so that they have to stop building - we can but live in hope.

Laura this is fine as long as the evacuate Kent Terrace and the south-western end Wellington crescent first. Michael.