Ogof Carreg Lem Reopened

Ogof Carreg Lem Reopened

Last Updated: 9th Feb 1998
6th April 1997
21st April 1997
6th May 1997
28th May 1997
1st June 1997
9th February 1998

On Sunday 6th April 1997, the entrance choke at Ogof Carreg Lem was passed, regaining access to the chamber below.

The site was originally opened in the early 1980's by Pete Francis and others from SWCC. After a couple of years of hard work a collapse in the entrance choke sealed the cave and those involved had a very lucky escape. Details of the original dig and a discussion of the potential of the area can be found in SWCC newsletters 97 and 106.

After being shown the site by Toby Dryden during the Winter of 1996, I managed to bully a few people into accompanying me to the site with a view to re-opening the choke. On 1st January 1997, the project kicked off with a vengeance. Since then, almost every weekend has seen an enthusiastic group of cavers struggling up Mynydd Ddu under the weight of scaffold bars, clips, timber and tools. The team has involved a very varied range of abilities from experienced cave diggers to those just out for a walk but willing to help out with the carrying and some of the most dedicated team members are still provisional members of SWCC. The project has also involved others from outside the ranks of the club.

The re-opening of the entrance choke has taken 101 man-trips and the project has consumed large quantities of scaffolding, partly funded by SWCC. The entrance chamber beyond the choke is quite large and is a tantalising clue to what might lay beyond the previous limit of exploration. The original explorers were stopped by a tight bedding plane but digging technology has advanced and it should now be possible to bypass this obstacle into passage beyond. There are also other sites in the cave that may warrant digging. Some work is anticipated before we are able to reach the bedding plane as the cave takes large quantities of water from the surrounding catchment area and flood debris washes in.

The team has high hopes of entering the missing miles of passage to the west of the Dan yr Ogof system.

For the time being, those wishing to visit the site are requested to join the digging team on one of our regular weekend trips, rather than doing their own thing.

Everyone is welcome, whatever their ability. We usually meet at SWCC on Sundays at 10am. There are only two rules for digging at Ogof Carreg Lem: Have fun and make it 'Tim Sized'. See you on the mountain!

Tim Long.


The Carreg Lem Team (phase 1) has been:

Name Affiliation Digging Trips
Adrian ? B&DAC 1
Ali Garman SWCC/MCC/DD 12
Andrew "Roger" Gardner SWCC 5
Andy Harp SWCC/BUSS 2
Ben Lovett MCC/DD 5
Claire Hicks SWCC 2
Daniel Carter (Junior) 4
Dominic Wade SWCC 2
Dudley Thorpe SWCC 3
Gary Evans SWCC 3
Huw Jones MCC/BCC 1
John Wills B&DAC 5
Jon Jones SWCC/MCC/DD 9
Julian Carter SWCC 10
Kevin Munn SWCC/MCC/DD 1
Louise Maurice SWCC 1
Mal Jones ? 1
Malcolm Stuart MCC 1
Mandie Edgeworth SWCC/UWCMCC 1
Martin Groves SWCC 7
Pat Hall SWCC 2
Rhys Williams SWCC 2
Sam Jones (Junior) 6
Tim Long SWCC/MCC/DD 15
Will Knight DD 1

Total man-trips since 1st January 1997 102


Previous limit reached

The last two weekends have seen teams going in on both Saturday and Sunday. Initial progress found the cave still more or less open as far as the lowest part of the cave, where a low mud filled crawl had become silted in again.Work started to reopen this section which leads to the previous limit of the cave where the 'prime' lead is to be found - a stream crosses the walking size passage to disappear into a low bedding. Meanwwhile closer to the entrance Ben and Andy have been putting some effort into the left hand series, where a tight pot gains a small stream. Some progress ahs been made, but some blasting is required.

On Sunday 20th April a small team managed to dig through the low crawl to gain the original end of the cave. Ogof Carreg Lem is now officially full length again (plus a few meters more). The low crawl is yet to be made big enough for the larger members of the team, so some more work is required yet ! The bedding plane lead has now been reached and the site looks good. The team now needs to apply the delights of Bosch and Bang technology - just watch this space.

A few notes about the cave if your thinking of a visit; the cave is actually more pleasant than expected, though quite 'sporting' ! There are a series of U tubes which have to be negotiated which are 'tidal' due to the gravel etc in them. The larger members of the team seem to be constantly digging these out ! After the U tubes some pleasant walking passage is reached (with the odd flat out crawl and squeeze here and there!) before reaching the low mud filled crawl. This is currently a bit tight towards the end, but the floor can be easily dug out. At the end of this you pop out into a lovely walking sized passage. There are some nice formations and the draft disappears down the bedding with the stream.

Julian Carter (21 st. of April 1997)


Update from Tim

Since the last report from Jules that the original limit of exploration had been regained, several trips have concentrated on widening the bedding planes at the end of the right hand series. This is reported to be progressing well. A sample of rock from the base of the bedding plane has been identified as honeycomb sandstone, which is very good news indeed. This quartzite sandstone bed could be as little as 1m thick and below it lies the beds that contain most of Dan yr Ogof. There are areas in DYO where the passage breaks through the honeycomb sandstone (e.g. Dali's Delight area) so there is every reason to expect a way through. However, there are several ways into the bedding plane and it is not yet clear which will be the most productive to push - investigation is ongoing.

There are several other sites that warrant serious investigation and these projects are also ongoing. There is plenty to do and anyone is welcome to join the digging team - get involved or miss out on Wales' next major cave discovery!

See you on the mountain.

Tim (6th May 1997)


Another Update from Tim

After a couple of weeks of inactivity, we returned to commence work on the near bedding plane. The spoil from the large boulders obstructing the bedding plane was cleared and the first charge was set.

I had a look down the far bedding plane as far as I could thrutch (yuck). There is a very tantalising sound of trickling water in there somewhere!

Personally, I think it is still worth pursuing both bedding planes, because it seemed to me that there is a small anticline between them and I'm far from certain that they dip in the same direction. Also, there is a solid rock wall between the two. I think we need a few more trips before we can make a decision. If we take plenty of chemicals, we should be able to work on both.

The end of the far bedding plane is not quite 'Tim sized' so next person in, please try to make it a little wider.

The start of the right hand series, where the water sinks, has yet to be looked at. This is an easy day's digging for someone who doesn't want to negotiate the entire cave. Dudley and I are quite interested in having a look at this area, any other takers?

I still want to do a full-blown dye trace to DYO, with charcoal bags at strategic points within DYO, not just at the entrance. Does anyone wish to do this or shall I involve Bill G?

It was nice to have one of the original Carreg Lem diggers, Steve West, on the digging team. After several months with a bad back, Steve has returned with a vengeance with two reasonable digging trips in a row. It would be even better if the other original diggers would follow his lead and get back down the cave.

See you on the mountain.

Tim 28th May 97


From Jules

Arrived at the 'near' bedding plane. Plan was to clear the debris from the previous weeks blasting activity. the job was a good one and it took myself, Ben and Ali quite a while to shift the debris.

Once cleared we found the blast had taken advantage of a bit of a cross joint in the roof giving us about 2m entry. However prospects did not look brilliant. Virtually no draft and the bedding closes to a 15cm gap.

Thus went to have a look at the far bedding. The stream was very low. Spent some time clearing the results of the previous blasts and chiselling loose stuff out of the roof. Decided to head slighty right to where the roof rises a bit and we could see some small stals. Between us we drilled 6 and a half holes which Ali had loadsof fun knitting together in the confined space - the roof of the bedding looked as though it had Christmas decorations when he'd finished. All suitably frozen from laying down in a small stream for X amounts of time with a noticable draft we exited. I must add that we must remind Ali to charge his lamp - on entering the cave it become clear that his photon power was not what it should be !! but it's very difficult to get the lamp out of the car together with a charger.........

The bang was suitably set off and out we went to meet Huw Jones wandering about the entrance chamber.

The far bedding I feel is the better option - it's taking a draft and a regular stream which you can hear flowing.

Viva la Black Mountain

Julian Carter (1st June 1997)


From Tim

Progress at Ogof Carreg Lem has proved disappointing and the team has set a deadline, after which if no obvious way on can be seen, the bedding plane will be declared "dead". Another team may care to take up the challenge; at least the cave is open for anyone who cares to try. We are still looking at the area surrounding the bottom of the boulder choke at the entrance and the ajoining entrance into the 'right hand series'.

Disillusioned with Carreg Lem, the team has turned attention to another SWCC vintage dig at Ystradfellte, known as Ogof Pwll Derw. That famous old man of the hills, Toby Dryden, fount of all ex-SWCC digs, led the first expedition to this site, which is situated near the bottom of a large shakehole (Pwll Derw) that swallows a lot of water in wet wether. To date, work has concentrated on stabilising the old dig with scaffolding and cement and reopening the entrance after some movement caused it to be plugged by a 1-ton boulder.

Pwll Derw is a promising site, with the water having been traced to the Hepste resurgences over 3 Km away and a good draught. The digging is, however, somewhat interesting and not for the faint hearted. Anyone brave enough is very welcome. Don't spread this around, but it's a good site for a picnic and a few beers, BBQs are forecast in the summer months.

See you in the pit!

Tim Long. 9th Feb 1998

To which Jules replied "Not everyone is dis-illusioned with Carreg Lem!!! - I would have been up there last week if it hadn't been for a missing caver!! Carreg Lem ain't dead yet by a long way..... Love to all - Jules"


See Newsletter 123 2003 for the latest update on Carreg Lem!