Further work in Penyghent Pot
Thursday, 13 October 2005

Penyghent Extensions: flooding

The dangers of flooding in the Living Dead Extensions were unknown at the time that the report appeared in the ULSA Explorations Journal II in 1989. It is now known that these extensions fill to the roof in only moderate floods. The bivi camp at Norman Bates Motel above Eerie Pot was washed away three times between February 1991 and 1994 ! Floods of this severity are perhaps something of a rare event, but parties anticipating a trip into the further reaches of the cave should be fully aware of the flood hazard.

MINOR EXTENSIONS

Several minor discoveries were made during ULSA’s innumerable visits to Penyghent Pot up to 1994 during the dying days of the exploration of the Living Dead Extensions. Many of these are located in the “old cave”, ie the section of cave known up to 1986 before the first major ULSA extensions in the Friday the 13th Series. Although all these discoveries are only minor in nature, they have never been written up, and the combined length of the new passages extend the known cave in Penyghent by a total length of about 560m (including the known passage in Spike Pot prior to 1994). The present length of the cave is therefore about 5.65km (3.51 miles).

These small extensions consist of the following:

?Old cave?

? Twin Falls Pitch
? ?False? Spike Pot Inlet – head of first pitch
? ?True? Spike Pot Inlet (connection to Spike Pot)
? Hunt Pot Inlet ? attempted connection to Living Dead Extensions
? Hunt Pot – extension 1
? Hunt Pot – extension 2
? Upper Main Stream Passage avens
? Upper Main Stream Passage inlet
? Blind Pot Series
? Eerie Pot
? Downstream Sump

Living Dead Extensions

? Acieed Aven
? Better Dead Than Welsh
? Cholera Canal
? Too Long Gone

Twin Falls Pitch

On the 24th September 1989, Jon Watt investigated a low bedding plane on a shelf just upstream of the 1st pitch (“Twin Falls”). A dig through soft flowstone allowed a route to be forced along a very low crawl for about 15m. The passage ended at a choked, but strongly draughting bedding plane located just below an area of shakeholes on the surface.

?False? Spike Pot Inlet – head of first pitch

A rather squalid inlet passage joins the main Penyghent Pot passage at the head of the first pitch (“Twin Falls pitch”), the water from this inlet forming the second waterfall at the pitch (the other fall being the water from the entrance crawl).

This passage is referred to as the ?Spike Pot Inlet? in Northern Caves, and on the ULSA 1989 PYG Pot survey, because in 1954 Arthur Gemmell carried out a dye test which established that the water in this inlet cames from a small stream sink located at NGR SD in a shallow valley SSW of the Penyghent Pot entrance and NE of Spike Pot (Gemmell, 1954). ULSA surveyed the inlet in 1972 to where the passage was found to end at a low section choked with cobbles.

In May 1990 Andy Tharratt dug his way through the cobbles at the upstream end of the inlet to gain a further 30m of awkward passage ending at a slab blocking further progress. The slab has not been passed as yet, but the passage can be seen to continue beyond.

?True? Spike Pot Inlet (connection to Spike Pot)

The true inlet for the Spike Pot water is a bedding plane at floor level under the true left wall of Easy Passage, about halfway between the 1st pitch and the 2nd pitch, just upstream of some dry oxbows on the true left of the passage. It is actually fairly obvious since it is the only active inlet on the true left side of this passage (the water was used as a regular carbide rewatering stop on the way out from Living Dead Extension exploration trips but the inlet was missed completely until 1994).

Spike Pot was dug open over various trips in November 1994 by Paul Monico, Andy Tharratt, Malcolm Bass, Julian Clamp, Isabelle Grieve, and Simon Yearsley. PM, MB, and SY reached ?the end? of Spike Pot (as described in Northern Caves) on 19 Nov 1994, a low airspace area over shingle in a flat out bedding plane that was easily bulldozed into new ground. PM and AT dug this new ground a week later, and in early December 1994 PM, MB, SY, and JC pushed on through an enlarging bedding crawl to ultimately emerge in the main PYG streamway. Total new passage (from memory) was about 100m.

Hunt Pot Inlet ? attempted connection to Living Dead Extensions

Attempts to establish an easy route into the Living Dead Extensions proved frustratingly unsuccessful.

The dig in Hunt Pot Inlet at the vocal connection with The Living Dead Extensions was dug extensively between July 1989 and May 1990. Several tons of boulders were excavated and blasted from a heavily shattered rift aligned on a fault, until access was gained to a short crawl leading into second rift running parallel to the original dig site. At its most advanced stage the dig was located directly over and only 1.5m vertically above the passage in The Living Dead Extensions. Unfortunately the heavily shattered nature of the dig caused serious stability problems and this resulted in several major collapses. An indication of the quantity of rock that fell from the roof can be gained from the size of the rift along which the dig was located. Originally this was less than 1.8m high: by May 1990 it had increased to over 9m in height. Several major collapses occurred (the most severe of which lasted for over an hour!) and the dig was finally abandoned when one ULSA member had a rather fortunate escape. The continuing exploration of The Living Dead Extensions up to 1994 thus took place via The Highway to Hell.

Hunt Pot Inlet – extension 1

After the vocal connection with the Living Dead Extensions in June 1989, Paul Monico took a wrong turn on his way back through Hunt Pot Inlet and entered low crawl off an oxbow on the western side of the main passage. The passage had obviously not been entered before as the floor was covered with delicate rock flakes that broke under the caver’s weight. After negotiating a crawl for about 120m, the roof lowered to create a 4.5m long duck with about 7.5cm of airspace. Encouraged by the shouts of Andy Tharratt who was in the main passage, the duck was braved and found to emerge in another oxbow which in turn led back into the main passage. This previously unknown and rather obscure oxbow totals about 137m in length; it seems likely that it has only become exposed since the water level in Hunt Pot Inlet dropped when the sump stopped flowing in the mid 1980s.

Hunt Pot Inlet ? extension 2

In March 1990 Paul Monico and Dave Brock made a small extension off the short oxbow at the upstream end of Hunt Pot Inlet. This oxbow was formerly submerged and formed the right hand of the two Hunt Pot Inlet sump pools. When the Hunt Pot Inlet sump stopped flowing in the mid 1980s the water level fell by 1.8m and the sump retreated by over 30m; the right hand sump was thus exposed as a dry oxbow.

Sliding up and over a cobble bank on the northern side of the oxbow led into a wide but low, silty bedding heading in a northerly direction. After passing through a pool, a low wet section was encountered where the way forward continued with a squirm between a mass of fallen flakes. Further progress was halted at a fallen block although the passage could be seen to continue beyond. The offending block was removed a week later to gain a further 4.5m of very low and miserable wet passage with a rapidly diminishing airspace. To date this has not been forced to a definite conclusion, the total length of the passage from Hunt Pot Inlet being approximately 46m. The passage is interesting as it trends in a north – north easterly direction, i.e., towards Hunt Pot and may possibly be an inlet into the former Hunt Pot Inlet sump. Further progress would probably necessitate the use of a bottle.

Upper Main Stream Passage ? avens

In October 1989 Adrian Mellor and Malcolm Bass bolted up two of the three large avens in the Upper Main Stream Passage. One gave access to 6m of short passage, the other was found to close up completely. The third and final aven was partially climbed, the ascent being completed months later by pswire , Martin Kocsis and Paul Finch.

Upper Main Stream Passage ? inlet

In March 1990 Jon Watt found an active inlet off an oxbow that was not marked on the 1972 ULSA survey. The passage was a comfortable crawl followed for 15m until the wet nature of the passage prompted a retreat. It was pushed to a conclusion and surveyed a week later, the passage proving to be an unknown oxbow off another oxbow. The surveyed length is 76m.

Blind Pot Series

This rarely visited part of the cave was surveyed by ULSA in 1974. During this 13+ hour survey trip Dave Brook entered a low crawl south west of the Helix Series which was followed to a point where the way on was partially blocked by flowstone. Due to its particularly squalid nature, the passage was not surveyed to the usual ULSA standard (in fact it wasn’t surveyed at all!); as a result it appears on the 1989 ULSA Penyghent survey as a sketch
only.

In 1990 Nick Walmsley spent a couple of trips attempting to establish the destination of the passage. On the second occasion vocal contact was made with Dave Kapur who was then situated in the oxbow off Psycho Crawl. The two cavers estimated themselves to be only 10m apart but the low nature of the passage has prevented a physical connection. The crawl thus appears to be yet another oxbow perched on the complex Hunt Pot Inlet / Friday the 13th / Living Dead Extensions level.

Eerie Pot

An examination of the south east end of the bottom of Eerie Pot by Andy Tharratt revealed a traverse over deep water into a previously unknown section of walking-sized passage. This was followed for approximately 35m to a deep-looking, 1.8m square sump. The sump remains undived but from its position it seems likely that it probably connects with one or more of the undived flooded pots in the Blind Pot Series; if this is the case the sump almost certainly acts as a flood overflow carrying flood water from the Blind Pot series into the main Eerie Pot sump (which in turn almost certainly connects with the main downstream sump).

Eerie Pot

Part way down the Eerie Pot pitch there is a low bedding plane passage in the wall which was originally noted by ULSA members during a survey trip in 1973. This squalid little passage remained unentered until April 1991 when Andy Tharratt investigated and found a low crawl heading in a direction. The passage was followed for only 15m to a duck with around 7.5cm of airspace; to date the passage has not been forced to a conclusion.

Downstream Sump

Dave Brock continued the work begun by Adrian Mellor in the downstream sump in the early 1990s. The sump was explored for a distance of 215m and attained a maximum depth of -36m. Many dives took took place, although several were abandoned due to rather unfortunate circumstances. One in particularly notable fiasco developed when the rock bridge over the sump collapsed due to the excessive weight of sherpas. The sump pool turned into a maelstrom of panic as several hundred weight of rock and sherpas landed on the diver’s head. Two of the sherpas narrowly avoided being dragged into oblivion as the perch to which they were attached sank into the depths, complete with the end of the diving line and all the decompression kit !

Cholera Canal

This canal is the northerly continuation of Paradise Lost and was reported in the ULSA Explorations Journal II as becoming too low for further progress. However, low water conditions in May 1990 enabled Malcolm Bass and Paul Monico to progress a little further to a point around 80m from Paradise. Here a large mud bank prevented access to a continuing low airspace canal but to the left a large sump appeared to lead off under the left hand (north) wall.

This “find” proved remarkably convenient as it provided a satisfactory explanation as to the source of the water flowing through Cholera Canal, Paradise Lost and the Too Long Gone streamway. Sadly, however, this illusion was to be shattered [exactly] three year later when Malcolm Bass returned to dive the sump. Taking advantage of a set off bottles which had languished here for over two years, a dive in the sump found only a blind silty undercut with no submerged continuation. The diver returned the 80m distance back to Paradise by swimming along the canal; no other inlet were noted.

Acieeed Aven

This initially promising-looking cross joint aven adorned with a large flowstone formation was climbed by Malcolm Bass in May 1990. The aven is completely blocked by flowstone at a height of 11m.

Better Dead Than Welsh

This is a low crawl leading off from Relief Junction at the start of the “larger” stuff in the Living Dead Extensions. It was first entered in 1988 and followed for 12m to a junction. To reach this point involves some several hundred metres of continuous flat-out crawling and as a result the passage remained a loose end until March 1990, the prospect of further crawling being sufficiently off-putting to deter even the most determined explorer snapping up one of the unexplored loose ends in this remote area of the cave.

The passage remained a loose end until March 1990 when Andy Tharratt finally forced it to a conclusion. At the junction 12m from Relief Junction, the right hand branch proved to be an oxbow leading towards a short passage “upstream” of Relief Junction i.e., beyond Relief Junction on the route to the choked vocal connection with Hunt Pot Inlet. The left branch led through two very low ducks to emerge in Turkey Tweezer Passage.

Too Long Gone

Work at the extremity of the system concentrated on a small passage located about 1m above the normal water level at the west end of the Too Long Gone Sump.

Known as the “sump tube”, the passage consists of a tight and very awkward sideways crawl through which an enticing roar of water can be heard (presumably the Too Long Gone water beyond the current limit of exploration). Over several trips by various cavers involved in the exploration of the Living Dead Extensions up to 1994, a too narrow passage was enlarged with the aid of a lumphammer and ultimately forced to a constriction about 35ft from the Too Long Gone sump. It is an exceptionally tight and awkward passage, and is only fully accessible to smaller cavers. The narrowness of the passage at the far end (if you can even get there) prevents any real progress from being made as it is not really possible to dig it. The enticing roar of water does however remain ?..

Dye Testing

Efforts to establish the source of the water in The Living Dead Extensions proved embarrassingly unsuccessful. Since 1989 several tests by Paul Monico and Andy Tharratt (with the help of others) using optical brightening agents (OBA) resulted in failure, mainly due to floods washing the detectors away. A partially positive result was obtained in 1990 when traces of OBA were picked up on detectors placed in Cholera Canal and Too Long Gone, retrieved a few weeks after a large quantity of dye had been hurled down Hunt Pot.

Sadly, however, this test is by no means conclusive and to date the source of the water still remains unproven. Current thinking still suggests the water is that which used to flow to Hunt Pot Inlet (i.e., the water from Hunt Pot and Hull Pot – both positively tested to Hunt Pot Inlet – and possibly Little Hull Pot). Several good reasons indicate this may be the case. Firstly, the quantity of water is roughly about the same as used to flow out of Hunt Pot Inlet before it ceased flowing; secondly, on warm days the water in Cholera Canal is noticeably warm, as indeed did the water in Hunt Pot Inlet on similar occasions; thirdly, and perhaps most importantly, this theory offers a remarkably tidy explanation of what happens to the river that used to flow through Hunt Pot Inlet!

This work was mostly done in 1989ish-1994ish
Please note that although I have posted this material it was sent to me by Paul Monico.
Add comments