Swildon's Water Levels...

[mrodoc]

I cannot say its every trip I was more assiduous in my younger days and now again.  I wish I had started even earlier as my first trips would have been in 1965. The only thing I have extant from the period is a school essay 'Stuck in the Bunghole' describing a trip into Holwell Cave when we took some cousins caving and one didn't like it all!

Old Ruminator's memory is selective. He and Rose still chunter on about another cousin's black bra and that was forty years ago!

 

[The Old Ruminator]

Oh no Peter. It wasnt a miracle after all. Does that mean 45 years of religious fervor is for nothing? I still remember it differently as I am sure we took the ladders for the 40 and made the decision at the last minute. In any case you should not have been drinking in the Queen Vic aged 17. I am surprised you can even still read your logs after Peter Rose and I vandalized them. As for your cousin's underwear. Nope does not ring a bell with me. Let it be known that the only accident I ever had in relation to Swildons was falling down Mr Maine's barn stairs. Still this tomfoolery is way off topic. I think I might advise folk to give Swildons a miss this weekend.

 

[egons pete]

Remember July 68 very well walked over to swildons entrance it was just a whirlpool of brown water could not see the entrance at all. Decided to return home to portishead road across velvet bottom impassable turned back, blurring ton coombe impassable etc etc etc took many hours to eventually return what a day!

 

[jasonbirder]

T'was nice and sporty yesterday...lots of water in the streamway...(wouldn't advise for novices etc)
Surprisingly not much bailing to be done on the round trip...but Sump 1 felt quite snug...don't know if recent weather has washed lots of gravel in

 

[Rich West]

On July 10th 1968 a post work drink in Clifton was cut short when the flat roof collapsed under the weight of water. I set off for home in Hallatrow at about 7:30pm and, after becoming stuck in floodwater just outside Whitchurch and after being overtaken by the army in an amphibious truck, eventually made it as far as Pensford by 10:30 only to find that the road bridge had been washed away and many peoples houses devastated. After a night stuck in the car I eventually got home via Keynsham, where 3 people had drowned, at 4:30pm the next day, more than 20 hours after leaving Bristol. The most vivid memories of my first post-flood trip in Swildons are the loss of the Forty, the huge ammount of rock that had been moved downstream and the strange sight of masses of hay high up in many parts of the cave. How lucky that this storm did not hit at a weekend.
Enclosed is a link to some excellent photographs of the devastation around Cheddar:-
http://www.northsomersettimes.co.uk/home/flood_gallery_1968_1_1451589?id=23&storyId=1

 

[The Old Ruminator]

Excellent images Rich. I think the exposed pipe was close to Reservoir Hole.

 

[Rich West]

The floods coming down Velvet Bottom & Longwood ripped up vegetation which then caused damming at various obstructions & drystone walls. When the volume became too much these failed in succession sending pulses on down valley to the next obstruction causing another failure. The combined streams rushed into the Gorge at the Blackrock junction, surged down the road and scoured the deep holes at the edges of the road that can been seen in the photographs. I think that left the pipe, which delivered water from the reservoir, hanging in "mid-air". Did this fracture under its own weight and release the whole contents into the deluge which engulfed the lower Gorge?

 

[cap n chris]

The breaching of the road causeway at Charterhouse may have been the main catastrophic failure initiating the subsequent domino effect you neatly outline Rich.

 

[Hughie]

Thanks for posting those pics, Rich. I've lived just outside Blackford for 47 years, and not seen those pics before. I would have been two and a half at the time. At that time the levels and moors just south of Blackford would of been heavily populated with livestock, and I remember my father telling me of how all the local farmers worked together to shift as many of the animals to safer higher ground. In severe weather the area can flood extremely quickly - during the wet season last year (after a 3 incher) - we had to move a bunch of cattle fairly quickly, and the field went from being very wet to completely submerged within about 40 minutes.

 

[Rich West]

The Cap'n is correct - the major surge would have been caused by the catastrophic failure of the road causeway at Charterhouse. Each failure acted as a domino effect on the downstream obstructions - This happened to the north of Mendip where there were no collapses of a comparable size to the one at Velvet Bottom but many vegetation / stone-wall / fencing dams which burst in succession causing, for instance, the Pensford bridge failure, and my having to spend a hungry, cold, wet night in the back of my van.
There are many historic photographs and memories recorded in the journals of the major Mendip clubs. One which is easily accessible is that of the Mendip Caving Group:- http://www.mendipcavinggroup.org.uk/sections/upperflood/history_02.html
For a definitive account of this event try:
"The Great Storms and Floods of July 1968 on Mendip"
by Jim Hanwell & Malcolm Newson
Wessex Cave Club Occasional Publication Series 1 Number 2 October 1970

 

[The Old Ruminator]

Another factor was straw from fields and loads of leafy branches which blocked rivers then gave way under the pressure of water. Possibly a winter flood with the same rainfall would not have been so catastrophic. There may have been additional run off with the drier ground.

 

[The Old Ruminator]

As a local historian and collector of images I have photos of other disastrous floods.

Taunton was badly flooded in 1960 ( I remember it well ). Flood relief schemes stopped that reoccurring in 1968. The villages on the moors were deluged in 1927 when the Tone/Parrett burst its banks at Curload. Other flood episodes have continued back through time. Essentially flood episodes are not unusual they form part of our inherent cycle of weather patterns which can reach extremes from time to time. More often than not this is exacerbated  by modern farming methods and large scale developments. There was also the extreme weather event in North Devon in 1952.

The worst post-war flooding disaster in Britain took place in the North Devon village of Lynmouth in 1952, in a tragedy which claimed 34 lives.

The flooding occurred on 15 August 1952, after nine inches of rain fell in the space of 24 hours.

The downpour caused a wall of water to surge down from Exmoor onto Lynmouth. The East and West Lyn rivers, which drop down from Exmoor, were swollen even before the storm.

Again a very localised event.

So to get back to the theme of the thread. There will be another such event on Mendip sometime in the future. Lets hope it will be well forecast and nobody is down Swildons. When I took my power boat exam the first question they asked was " what is the weather forecast ?" If you couldn't answer that you failed straight away. Perhaps cavers should be a little bit more careful in that respect.

 

[Rich West]

I well remember my parents horrified reaction to the Lynmouth floods as we had been holidaying in a caravan above the town only the week before.
However - Old Ruminator is wrong re the worst post-war flood - a massive storm surge hit the east coast on January 31st 1953 and caused the deaths of over 300 people in Lincolnshire, Norfolk, Suffolk & Essex.

 

[tony from suffolk]

Post The Flood it was sobering to see how high the floodwater came in Swildon's. The bits of straw and grass, which incidentally remained visible for months (if not years), showed the extent, with places like the Old Grotto flooding to the roof.

A grim reminder of what can happen and why it would be wise to follow Old Ruminator's advice on checking the weather forecast.

 

[The Old Ruminator]

Post The Flood it was sobering to see how high the floodwater came in Swildon's. The bits of straw and grass, which incidentally remained visible for months (if not years), showed the extent, with places like the Old Grotto flooding to the roof.

A grim reminder of what can happen and why it would be wise to follow Old Ruminator's advice on checking the weather forecast.

Copied and pasted a quote Rich which was correct at the time. As we can see these events are not really uncommon at all.

 

[And]

Went down Swildon's on Saturday and water levels were higher than average, but not that high. I saw water coming in from places I hadn't seen before though: down from Tratman's Temple and also pouring out of the dig before Sump 1. Maybe it always comes out of these places and I hadn't noticed or I forgot as I haven't been there in a while.

Here are a couple of interesting links on the floods of 1968:
Footage from the BBC http://www.bbc.co.uk/news/uk-england-bristol-18790002

and an interesting article from the Environment Agency http://www.publow-with-pensford-pc.gov.uk/pub/backlook/env_agency_leaflet.pdf

 

[Les W]

Went down Swildon's on Saturday and water levels were higher than average, but not that high. I saw water coming in from places I hadn't seen before though: down from Tratman's Temple

Water flows from Tratman's Temple in higher than average water conditiond quite often.

and also pouring out of the dig before Sump 1.

This is Priddy Pool Passage and it always flows from here although you might not notice it as it flows under a boulder to get to the stream. This is the water from the Black Hole series.

 

[bagpuss]

I've not been up on Mendip since before Christmas - what's it like flooding wise there at the moment? Has anyone been in Swildon's this week? Hoping to head there Friday day time, will assess what it's like on the day - it's looking dry Thursday, and dry Friday so I imagine the water will be at it's peak tomorrow after all the rain this evening. If anyone visits tomorrow can you report back please? Only looking to bimble round the upper series.

Thanks