Author Topic: Thrupe Lane Swallet  (Read 12479 times)

Offline nice but damp

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Thrupe Lane Swallet
« on: September 15, 2014, 06:24:33 pm »
Has anyone got any news regarding an update on how things are going with Thrupe after it was closed dues too flooding etc?

I had a look on the CSCC web site, but could find nothing on there mentioned since last year.

Cheers
Tim


Offline Cap'n Chris

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Re: Thrupe Lane Swallet
« Reply #1 on: September 15, 2014, 07:23:51 pm »
It is being worked this week, so I understand. An update on access will be forthcoming in due course.

Offline nice but damp

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Re: Thrupe Lane Swallet
« Reply #2 on: September 15, 2014, 08:27:03 pm »
Thanks Cap'n ...much appreciated.
Wish I was closer to help!......I may be over again in the next few weeks (during the week), if so, I'll give a shout out if help is still needed.

How much work has got to be done, do you know?

Tim

Offline Cap'n Chris

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Re: Thrupe Lane Swallet
« Reply #3 on: September 15, 2014, 09:24:08 pm »
ATLAS are the people to contact! (I just heard about it today as had volunteered to assist if diary allows, which it sadly doesn't this week).

Offline nice but damp

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Re: Thrupe Lane Swallet
« Reply #4 on: September 15, 2014, 10:01:55 pm »
Thanks Chris....I'll get in touch with them  :thumbsup:

Tim

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #5 on: September 15, 2014, 11:34:42 pm »
Ah, update, yes!
Not much to say at the moment, except that the Thrupe stream has temporarily been diverted to leave the entrance of Thrupe Lane Swallet dry. A temporary stemple has been installed in the adit above the entrance shaft to which we will attach a pulley for hauling up bags etc. So Wed evening, about six of the ATLAS team are going to start clearing out washed in stream debris etc. We will concentrate on the Ferret Run and below, this Wednesday, probably leaving the assault on Bamboo Aven area (down the Railway Series) for another day since that is far less stream dependant. A couple more hands could be useful on Wed evening. PM me if interested in assisting.

Maj.
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Offline nice but damp

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Re: Thrupe Lane Swallet
« Reply #6 on: September 16, 2014, 03:06:44 pm »
Hi Maj,

Many thanks for the update on the situation.

We come on over to Mendip pretty regular, so, when I am next on my way, I will PM you before hand and see if I can be of any help.
As I live in West Wales, it's a bit tricky for this week, but I'll check with "she, Who must be obeyed!" as to when we are due over next.

Thanks again for the update

Tim


Offline Thrupeman

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Re: Thrupe Lane Swallet
« Reply #7 on: October 13, 2014, 03:31:14 pm »
There seems to have been a bit of a lack of up to date info on whether Thrupe Lane Swallet has been re-opened or not. I'm happy to report its open for business once again!

The clearing operation on Wed 17th Sept resulted in several bags of washed-in debris, comprising mostly of logs and branches being hauled up to the surface from the start of the Ferret Run.

The bottom of  Perseverance Pot was found to have silted up causing the connection through to Slit Pot to be more constricted.

Cowsh Crawl had also silted up and was a duck about 2ft -3ft deep with about 1ft of air space. Some initial work has been done here to lower the water level by excavating the floor on the far side but a lack of suitable digging tools on the night resulted in only a few inches drop in the water level.

Most of the flood stream appears to have flowed down Bridge Rift & Avalanche Pot - this hasn't been checked as yet.

Its assumed that the cave beyond Butts Chamber has not been adversely affected by the flood.

The Railway Series and Plaster Passage, near the cave entrance, had obviously taken a big stream and was well scoured out and washed clean.  As a result the 'Sand Crawl' before Bamboo Aven was completely choked with sand and much effort was expended in bagging up as much as possible and hauling it to the surface.  Much sand remains, although the way is now open and its a case of pushing through as before.

The route into High Atlas via Chimney Pot was not checked but was assumed to be open as the flood had flowed across Bleak Hall and on down the Old Wells Road. This was completely blocked at approx 1/3 of the way down thus losing the further reaches of the OWR and the Bone Aven extension.

At the time of writing most of the Thrupe stream has been diverted into the Hobnail Hole dig area resulting in a completely dry TLS entrance shaft for a change.  Some water has now started flowing along to TLS as well but is sinking earlier along the cliff face leaving the entrance shaft still dry.

Enjoy!

Clive

Offline nice but damp

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Re: Thrupe Lane Swallet
« Reply #8 on: October 13, 2014, 05:19:56 pm »
Thanks for the update Clive, it's much appreciated

Unfortunately, My wife's ill health has dictated that we haven't been over to Mendip recently, so I  haven't been able to offer my assisitance.

To you and all the team involved, a huge well done and a big thank you to you all  :bow:  :beer2: :clap2: Without cavers like yourselves, where would we all be!
A Brilliant job well done too.

Thrupe is one of my Favourite trips on Mendip, so am glad it's back open for business

Many thanks guy's and Gals <;-0)

Tim

Offline Thrupeman

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Re: Thrupe Lane Swallet
« Reply #9 on: October 17, 2014, 05:26:25 pm »
Thanks for the kind comments Tim....

Since writing that TLS is open again, we have been at work in Hobnail Hole close by.  The recent rains have caused the stream to rise appreciably so much so that that our work underground in Hobnail would have been under a waterfall!  So, we have dammed off the route the stream was taking into Hobnail and returned it to its normal flow to the TLS entrance area.

This is only a temporary dam and would easily be removed by a party wanting to go down TLS but it would, of course, mean damming and diverting the full Thrupe stream back into Hobnail which would be a bigger job.

So at the moment its a very wet descent of the lower part of the TLS entrance shaft again.....

We have now broken up and removed the large boulders which had fallen from the cliff-face into the streambed by the TLS entrance.  Furgling with a long bar caused the whole stream to dive underground at this point but that was only temporary.  This didn't seem to affect the flow of falling water into the TLS shaft though.

More news as and when!

All best

Clive

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #10 on: January 09, 2015, 05:49:03 pm »
A couple of videos of TLS entrance yesterday.





Maj.
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Offline Hunter

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Re: Thrupe Lane Swallet
« Reply #11 on: January 09, 2015, 06:04:56 pm »
Looks a bit damp!

Offline nice but damp

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Re: Thrupe Lane Swallet
« Reply #12 on: January 10, 2015, 02:17:20 am »
Great little vids Maj....

Certainly looks slightly interesting on the entrance eh!

That must have been pretty awkward to clear with that flow of water to deal with!

Great work peeps

Tim

Offline Laurie

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Re: Thrupe Lane Swallet
« Reply #13 on: January 10, 2015, 02:29:06 am »
Didn't Dave King have something to do with it?
......or am I crap with facebook?
MNRC

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #14 on: January 10, 2015, 09:27:17 am »
You're not wrong there Laurie.

Maj.

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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #15 on: June 16, 2015, 08:14:20 pm »
Thrupe Lane Swallet update.

ATLAS are still currently digging Hobnail Hole therefore the Thrupe stream is still entering Thrupe Lane Swallet. Since the stream level is very low, although a little showery the Ferret and Perseverance Pot are passable at present without the need to divert the stream.

Over the last couple of years the stream has deposited a large quantity of gravel and cobbles on the far side of Cowsh Crawl, turning what used to be a damp muddy crawl into a duck with barely enough space to keep your head above water.
On Friday 12th June three members of ATLAS/MNRC descended Thrupe Lane Swallet and cleared a large quantity of gravel etc. from beyond Cowsh Crawl to increase the air space. Two large boulders weighing in at a guesstimated total of 2 tons that had allowed the gravel bank to build up were also moved. Cowsh Crawl, although it will remain as a Duck in all but drought conditions, is unlikely to develop into a sump which was a possibility before if left unchecked.

Most of the gravel, cobbles and rocks shifted were either stashed just beyond or washed down Bridge Rift. There will however be some gravel and possibly the odd cobble that didn't quite make the descent, but still intends to. A few flood pulses should help them on their way. In the mean time care should be taken if planning to descend Bridge Rift and Avalanche Pot.



Maj.

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Offline Cap'n Chris

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Re: Thrupe Lane Swallet
« Reply #16 on: June 16, 2015, 08:33:59 pm »
 :) Brilliant! - definitely needed doing! Well done. Any photos?

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #17 on: May 10, 2016, 07:44:31 pm »
The situation in Thrupe Lane Swallet remains pretty much the same. In winter and during wet weather there is quite a large stream flowing down the entrance shaft making it impassable. But at present there is a small stream flowing down. It is probably passable but this will depend upon the stream flow and the weather conditions at the time and how wet you're prepared to get.

The ATLAS diggers are still currently digging Hobnail Hole each week during the day, usually Fri or Sat, but occasionally Thurs or Sun. The Thrupe stream can be diverted down Hobnail Hole, but we would first ask if you could let the ATLAS diggers know. There are a number of active ATLAS members spread across the Mendip clubs, so it shouldn't be difficult to contact one of us. If we know in advance we may be able to divert the stream for you before an intended trip. It only take 5-10 mins to divert the stream and again to divert it back after your trip. 

Under no circumstances should the stream be diverted down Hobnail Hole if the Hobnail Hole gate is open. Hobnail Hole can easily be seen as you cross the stile in the dry stone wall between the layby and copse. It is a horizontal grill on the opposite bank of the stream, with the sole of a hobnail boot attached to the tree that over hangs the entrance :).

The work we carried out to Cowsh Crawl in June last year has worked well. On a recent trip the duck had been reduced to a 150mm deep puddle, although its depth may fluctuate it should not now sump and is unlikely to reach a depth of 300mm even with a large stream flowing down the entrance shaft and on down
Perseverance Pot.

Maj.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #18 on: May 24, 2016, 06:27:19 pm »
Last night (Monday 23rd May) three member of ATLAS descended the entrance of Thrupe Lane Swallet after first diverting the stream down Hobnail Hole. The team headed off down Plaster Passage into the Railway Series. Note that the remains of the old wooden tramway mentioned in MU5 no longer exist due to have been washed out by the various floods in recent years.

As expected the sand crawl approach to Bamboo Aven was once again blocked with gravel and silts (previously cleared to a caveable size in Oct 2014). After about an hours digging, this was once again passable. This now means that High Atlas is again accessible, entrance stream conditions permitting.

The route on through Bleak Hall and down the Old Wells Road is much as reported back in Oct 14. Approximately the last 3-5m of the end of the OWR (not 1/3 of the way down as previously reported) remains silted up with a small air space where a small stream will occasionally flow, and there by blocking the way on to Bone Aven. This could potentially be dug out in the future, although any spoil would probably need to be hauled back to Bleak Hall to prevent it washing back in during future flood events. Even then, future floods may still wash in mud and silts that line parts of the OWR.

Final task after exiting TLS was to divert the stream back down Hobnail Hole.

Maj.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #19 on: December 29, 2016, 01:36:26 am »
Update re Thrupe Lane Swallet.

The recent flooding has once again overwhelmed Thrupe Lane Swallet totally submerging the entrance. Thrupe Lane stream also washed a lot of shingle and silt down stream and deposited it in the depression and approach to TLS to a depth of about 1ft. Over the last few weeks members of ATLAS plus friends spent a couple sessions diverting the stream down Hobnail Hole and clearing the debris from the the approach to TLS. Further clearing is still required and ATLAS have scheduled another session for Fri 30th Dec.

We have currently left the stream flowing down Hobnail Hole which means TLS entrance is dry and accessible therefore open for caving. I dare say in a few weeks time we will recommence with stabalisation work in Hobnail Hole and will send the stream back down TLS. If I remember I will update when we do, but I would recommend getting in touch to confirm the latest state of play if you are planning a trip later in January and beyond.

Without carrying out this clearance the TLS gate may become blocked and access very difficult.



Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #20 on: April 05, 2017, 02:39:29 pm »
Update regarding Thrupe Lane Swallet (TLS).
As you will find there is an article in the latest copy of Descent (255) about the digging of Hobnail Hole which now connects with TLS. The break through point is in Upper Butts' Chamber. To get down from Upper Butts' Chamber into Butts' Chamber requires climbing down one of two routes, both of which are over unstable boulders (the floor of both Butts' and Upper Butts' Chambers consist of one large boulder slope). The preferred route to the right (left is more exposed and loose) involves climbing over three boulders, the centre one of which is bridged across the other two with a large cavity below and behind. From below it would be obvious that care would be required, but from above you wouldn't be aware of the perched nature of the boulders until it's too late. We are currently building up the cavity below with cemented rocks and a steel beam (steel beam due to be installed tonight) to stabalise the boulders.
Hobnail Hole won't be available for general trips until the stabalisation work is completed. Since Hobnail is visible from the road and has a tempting fixed ladder and vertical free climb below, the plan is to fit a CSCC padlock to keep access for cavers as easy as possible (the status quo will remain for TLS gate).
 
TLS is still taking the full stream at present.
The stream can be diverted down Hobnail Hole to allow access to TLS, but we would kindly ask if you could contact us first (one of the ATLAS diggers) if you would like a trip down TLS since we are usually working down Hobnail Hole on a Fri or Sat daytime and at present on a Wed evening too, days and times may change. We may even be able to divert the stream for you prior to a trip which would give the Ferret Run and Perseverance Pot longer to drain/dry out.
If you would like to lend a hand with the cementing etc. or our other project to re-open Bone Aven down the Old Wells Road, please get in touch, you will be more than welcome.

Thanks,
Dave.
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Offline mikem

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Re: Thrupe Lane Swallet
« Reply #21 on: April 05, 2017, 03:34:24 pm »
Dave, are you there over the Easter weekend?

Mike

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #22 on: April 05, 2017, 06:07:23 pm »
Not sure what our plans are yet, but I'm sure if you wanted a trip over Easter between us we can timetable ourselves accordingly.

Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #23 on: April 09, 2017, 12:18:04 pm »
Thrupe Lane Swallet over the Easter period.

The ATLAS Diggers will be continuing the work in Hobnail/Upper Butts' Chamber during the afternoon on Fri 14th April. When finished for the day the stream will  be diverted down Hobnail Hole and left as such until our next session on the evening of Wed 19th April.

This will mean that Thrupe Lane Swallet will be accessible during that period for any trips, weather permitting (a trip is already planned for approx 11am Sat morning). If you are planning a trip whilst the stream is entering Hobnail Hole it would be advisable to take a spade in case the dam has previously  been breached and requires a little fettling. Also we would not recommend a trip down Thrupe Lane Swallet if rain is forecast as the stream running along side the road that enters the depression and subsequently Hobnail Hole or Thrupe Lane Swallet, can react quickly and could breach the dam making an ascent of Perseverance Pot extremely aquatic if not impassable, The Ferret Run and the entrance climb will also be very aquatic.

Please do not climb above the obvious stabilisation works at the top of Butts' Chamber.  There is no restriction on access to the usual route to the Marble Streamway and ATLAS Pot.

Hobnail Hole is still undergoing stabalisation works and therefore is not yet available for general trips.

Thanks,
ATLAS.
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Offline Frigbob

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Re: Thrupe Lane Swallet
« Reply #24 on: May 16, 2017, 02:57:35 pm »
Hi Dave,
What is the likely access situation for TLS this weekend (Saturday 20th May)? Thinking about a trip down High Atlas, weather permitting. Don't want to upset any digging plans or infrastructure.
Thanks,

Tim.

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #25 on: May 16, 2017, 09:20:18 pm »
Hi Tim & anyone else interested in a trip down this magnificent Mendip cave.

Since the stream level is currently low we have diverted the stream down the Hobnail channel. This doesn't impede Atlas diggers access to Butts' Chamber via Hobnail Hole. Therefore so long as the stream is not overwhelming the dam, the entrance to Thrupe Lane Swallet is dry and accessible.

So have a good trip on Saturday.

Parking might be a little tight in the layby this Sat since we will be there too, so can I suggest you park towards one end or the other of the layby to maximise available parking space. But do ensure you are in the layby since quite often there are very large tractors roaming the area and they might take a fancy to the odd wing mirror ot two. If the layby is full, we can overflow into the yard just beyond the layby on the same side of the road (remember to close the gate when leaving).


The usual Atlas culprits will be luncheoning in or by the Ferret Shed on Sat before heading underground, loaded with cement and gravel etc for the continuing stabalising of the boulders in Butts' Chamber. The end is in sight and we hope it's not too long before we fit a CSCC padlock to Hobnail Hole entrance gate - watch this space! 

Regards,
Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #26 on: May 20, 2017, 09:13:34 pm »
Hi,

The ATLAS diggers were at it again down Hobnail Hole to continue cementing the boulders between Upper & Lower Butts' chambers. With the Hobnail channel currently taking all of the stream, the entrance to Thurpe Lane Swallet was very dry. We did experience a slightly drippier run down through Hobnail to reach Butts', but not enough to cause a problem even on our exit after some heavy rain fall on the surface.

Whilst underground I took a look at Cowsh Crawl and as expected this was dry with no water entering from Perseverance Pot at all.

So at present, further rain fall permitting, now is a good time to take a trip down the Marble Streamway to Atlas Pot via the Ferret Run & Perseverance Pot. But obviously bearing in mind any anticipated rain fall and the likely hood of the dam being overwhelmed or breached.

Dave.
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Offline obelix

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Re: Thrupe Lane Swallet
« Reply #27 on: July 28, 2017, 05:18:24 pm »
I left a rope behind on Thursday, 25m of white 10.5mm, just inside the entrance. If someone does this trip in the next few days and lives in or near Bristol, or Shipham, or Yate please collect it and pm me by Sunday night and I will collect it from you and be very grateful.
Otherwise please leave it there as I can collect it on Monday.

Even after lots of showers the entrance was really dry, not even a puddle between Slit and Perseverence, or Cowsh crawl, though there was  enough water for entertainment in Marble streamway and Atlas.  The Surface dam and drain working really well and giving confidence for a really tiring trip.
Thank you diggers.

Offline mikem

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Re: Thrupe Lane Swallet
« Reply #28 on: July 28, 2017, 07:08:10 pm »
No sign of water in West Twin Brook, so although the showers are heavy they are not overflowing the aquifer...

Mike

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #29 on: July 29, 2017, 06:36:06 pm »
Hi Obelix,

I gather the rope have currently been put in the Ferret Shed, our ATLAS diggers store etc.
I'm about on Mendip and will be over that way tomorrow (Sunday) morning, so I can either leave them where you caa gain access to them or I can bring them back to the MNRS (Green Ore, near the Plough Boy pub) whichever is easiest for you.

Cheers,
Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #30 on: July 30, 2017, 09:26:54 am »
Hi Obelix,

PM's sent yesterday and today.

Cheers,
Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #31 on: July 31, 2017, 05:33:09 pm »
Hi,

On Sunday I found myself over East Mendip, not really much of a surprise, but whilst heading home I drove through a torrential downpour. So I thought it an idea to go and have a look at the TLS stream. Initially the stream was only slightly up and the full flow still happily disappearing down the Hobnail sink, but then it changed quite dramatically over the next half hour or so. The stream came up and started to find ways around the dam and  sinking below the cliff face some 5m short of TLS entrance shaft. The level carried on rising and soon the dam and the sink at the end of the Hobnail channel were overwhelmed. The stream then reached the TLS gate and any debris leaves & twigs etc that washed down started to block up the gate and before long the level was 3/4 up the gate.
Although TLS is now more accessible, a careful check of the weather forecast is a must. The stream can respond quickly and make Perseverance and the entrance pitch impassable.
Hopefully some photos below.

Dave.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #32 on: January 28, 2018, 12:32:53 am »
Hi,

Update on Thrupe Lane Swallet & Hobnail.
As soon as I receive a new CSCC padlock it will be fitted to the Hobnail entrance grill, but in the mean time 
I wouldn't consider a trip down either at present until the weather improves and stream levels drop and some clearance work carried out.
A few photos taken Sat 27th Jan.


Dave.


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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #33 on: March 05, 2018, 07:03:29 pm »
Re Hobnail Hole:

This does not have a CSCC padlock on it as yet. There was a plan to put one on before Xmas, but it was felt best to wait for imminent new padlocks. Since Xmas there has been substantial flooding, covering Hobnail Hole and blocking the entrance to Thrupe Lane Swallet. Also Hobnail Hole is currently under a 4ft snow drift, so Hobnail still remains unavailable until substantial clearance work has been done.

There is a plan to have a working day or weekend over there before Mendip Cave Fest to get TLS and Hobnail open for business. A rough plan is to light a BBQ and ask cavers to come over and have a social working day or two to get it all cleared.

Will post details when a plan is made.

But an idea of numbers of interested cavers would be useful  :)


Maj.
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Offline Maj

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Re: Thrupe Lane Swallet
« Reply #34 on: April 15, 2018, 02:19:06 pm »
Latest update:-

With the recent bad weather it has been difficult to arrange a weekend to clear Thrupe Lane Swallet entrance. But last weekend four members of MNRC (Nick P, Ian B, Mark C & Dave K) spent a few hours carrying out some clearance work.
 
The Hobnail stream channel was partially cleared allowing the stream to be diverted down Hobnail Hole. This then enabled the clearing of TLS gate and dig out a lot of the silts, shingles & sludge that had been deposited in front of of the entrance. In all a guestimated 1 tonne of debris was shoveled and ferried up the steps in dustbins and deposited clear from where it might get washed back in. 

There is still a lot more to clear in due course, but for the time being TLS is open for business (in time for Mendip Cave Fest) weather and stream conditions permitting. 

Hobnail Hole now has a CSCC padlock on the gate and is also open subject to weather and stream conditions.

WARNING Both Hobnail & TLS can be become very aquatic and impassable when water flowing down.

Note also that we had cleared TLS gate of debris last weekend and left the stream flowing down the Hobnail channel for a TLS trip on Friday. The rain on Tues night was enough to breach the dam and wash more debris towards and half covering TLS gate.

WARNING The stream can react quickly to rainfall, I have watched the level rise from nothing entering TLS to a raging torrent in about 1/2 hr of heavy rain (scroll up to earlier post).

For information on Hobnail Hole see article in Descent issue 255 (Apr/May 2017) "Cobbling it All Together"
If planning on a trip down either Hobnail Hole or TLS, bear in mind you may need to clear debris from either gate and the Hobnail channel grill, possibly rod through the Hobnail Channel grill (5ft length of angle iron behind green shed, longer bar or drain rods might be useful), rebuild dam/divert stream.

To ensure other cavers that may arrive after you have begun your trip don't divert the stream down the entrance you have descended, leave the gate open. Although TLS entrance is free climbable, it is best laddered or SRT'd, as this will give a better indication that there is a party down there. I'd also recommend you think about a few "what ifs" ie someone fly tips grass/hedge cuttings up stream that may then wash down and block either TLS gate or Hobnail channel grill (this has happened). Kids playing in the stream, changing the course of the flow (this has happened on another dig less than a mile away). Leave a robust ETO, or you might consider someone on surface watch.
 
If you would like any further info about TLS, consult MU5.
For further info on Hobnail (kit requirements etc), feel free to contact myself or one of the ATLAS diggers.

Dave.
Confucius say "War does not determine who is right, war determine who is left."

Offline tim.rose2

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Re: Thrupe Lane Swallet
« Reply #35 on: November 28, 2019, 09:19:08 pm »
Anyone able to give a current update on Thrupe?  Is the cave accessible / what are current water levels like?  Considering a trip on Sunday as there's only a bit of light rain on Saturday forecast between now and then at the moment.  Would be looking at the usual trip down Perseverance pot, marble stream-way and atlas

Plan B is go play somewhere else! 

Thanks in advance.

Offline mikem

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Re: Thrupe Lane Swallet
« Reply #36 on: November 28, 2019, 10:55:27 pm »
Wookey was relatively wet tonight, which ain't a good sign for Thrupe...

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #37 on: November 29, 2019, 09:51:53 am »
The gate on Thrupe Lane Swallet is half choked with stream washed debris and will require clearing before access gained. The Hobnail channel requires digging out again as it will every couple of years, although it can still currently take a stream.

A trip down TLS will depend on a couple of things:-
1. Whereabouts the surface stream is sinking.
2. Which route ie Railway Series or Perseverance/Slit Pot.

The stream sinks in various locations between the Ferret Shed and TLS gate which include:-
Hobnail Channel, large depression to the right of the stream (facing down stream), where the stream first meets the cliff face, under the rock & log dam by the cliff face, various points along the cliff face before it reaches the gate. 

If all the stream is sinking before the rock & log dam it doesn't seem to enter the entrance shaft and Ferret Run and hence Perseverance should be okay.
As soon as the stream goes beyond the rock & log dam this water emerges in bottom of the entrance shaft and will make perseverance wet at best and impassable at worst.

If planning a trip down TLS I would recommend ensuring that a reasonable dam is re-established diverting all of the stream down the Hobnail Channel but also suitable to cope with any increase due to further possible run off.
This time of year I would also recommend rigging a ladder down into King Cobble Hall by entering Hobnail Hole, such that if you find on your return Perseverance is too wet to climb you have an alternative exit. Hobnail will remain passable albeit wet for a couple of short climbs except under extremely wet conditions.

The Railway Series remains accessible provided the entrance pitch is not impassable due to water flowing through the gate and straight down the entrance.


Another interesting point of note is that since the stream no longer goes through the pipe under the road before the Ferret Shed, Chimney Pot (up slope from Bleak Hall on route to Wuthering Heights etc) seems to now be permanently dry. Making trips to High Atlas and Wuthering Heights more reliable.

Hope this helps,
Maj.
 
Confucius say "War does not determine who is right, war determine who is left."

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #38 on: November 29, 2019, 09:54:43 am »
To add:-
We have had a lot of rain in the last few days.
I can pass by TLS later today and update stream conditions accordingly.

Maj.
 

Confucius say "War does not determine who is right, war determine who is left."

Offline tim.rose2

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Re: Thrupe Lane Swallet
« Reply #39 on: November 29, 2019, 10:29:57 am »
Thanks for the info Maj.
Sounds like it's best left until the spring if the entrance needs clearing and streams redirecting.  We won't have time this coming Sunday as I've a deadline to get home.
For future reference, is Hobnail fitted with the new or old CSCC keys?
Will go with plan B this weekend.
Cheers
Tim

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #40 on: November 29, 2019, 01:15:02 pm »
Hobnail has new CSCC padlock fitted.
 
See CSCC website for list of caves with new padlocks fitted.

http://cscc.org.uk/wiki/doku.php?id=news:start   
 
But the recommendation is still to take old and new keys in case padlocks changed since list last updated. 
 
Maj.
Confucius say "War does not determine who is right, war determine who is left."

Online Alex

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Re: Thrupe Lane Swallet
« Reply #41 on: November 29, 2019, 01:34:19 pm »
Just saying.... the stream would flow a lot more freely without a gate  :chair: :tease:
Anything I say is represents my own opinion and not that of a any club/organisation that I am a member of (unless its good of course)

Offline mikem

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Re: Thrupe Lane Swallet
« Reply #42 on: November 29, 2019, 05:41:57 pm »
& all the debris would block up the passage again, which is a lot harder to clear than the gate...

Offline Maj

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Re: Thrupe Lane Swallet
« Reply #43 on: November 30, 2019, 11:41:17 am »
Indeed, without the gate debris washed down the stream, which has included in the past leylandii cuttings fly tipped into the stream along the road as well as autumn leaf fall and various branches, logs, twigs etc. would find itself washed straight down the cave and potentially cause issues within as it has done in the past. The ATLAS team plus other Mendip cavers have put in an awful lot of time and effort to maintain access to TLS by keeping the stream clear and clearing the entrance gate, digging out the Hobnail channel etc when practicable. When you approach TLS, before reaching the steps down to the entrance on the right you may sometimes notice a large mound of mud, silts and composting material that has been cleared from the entrance.

If anyone is interested in assisting with the next clearing session feel free to get in touch  :) If I remember I will post details here, although sometimes it is at short notice being weather and ATLAS team availability dependent.

Think of the gate as more of a hinged grill to catch debris. There is no lock on the  ̶g̶a̶t̶e̶  grill so no key required for access, no restriction for access, no permission required,  just swing the grill to one side and retain with hook on chain. But please remember to unhook and close the grill after a trip.

Hobnail Hole does however have a CSCC padlock (keys readily available) on its gate since this is visible from the lay by when the foliage is low and with a square stone built entrance shaft with  fixed ladder could be too inviting to the un-aware.

Maj.
Confucius say "War does not determine who is right, war determine who is left."

 

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