New Stream Sump. A series of four dives were made into the previously unexplored sump at the end of New Stream Passage. The sump starts at a deep flooded rift which bottoms out at 35 ft. A comfortably sized tube leads off, meandering gently down dip for 450 ft. reaching a depth of 55 ft. at a cross rift where a small tube leads to the left. A layer of more cloudy water at roof level indicates the addition of a small inlet flow down the cross rift. The murky water flowed out entirely down the small tube, which was explored for only thirty feet or so. The way to the left in clear water was followed for 30 ft. to the bottom of a boulder slope aligned on the same cross rift as the inlet. The boulder slope was found to be very unstable, consisting of rounded stream-washed cobbles banked up by flood water into a slope of 60° or so, with only about 18 in. of space between them and the roof. Passing this will be a risky business, as a trundle could quite easily bury the diver.
R.J.S.
Aim: to extend the system downstream.
Three dives were made into the main downstream series. A line was laid through sump 1 which was found to be about 60 ft long and largely clear, apart from the odd tree trunk or so. Sump 2 was rigged with free diving lines although one bolt remains to be put in to make free diving possible with complete safety. The sump is done in three parts of 4 feet, 8 feet and 10 feet and the bolt remains to be placed in position between the 8 & 10 foot sections, where the diver surfaces in deep water. In the third downstream sump, previously dived but not passed by Alf Latham (NL.24:19) air space was reached after 90 ft. (27 m) and about 100 ft. of large river passage was explored to Sump 4, which was passed after 10 ft. to yield a further 50 ft. of smaller river passage leading again to the inevitable sump.
It was with hopes high for a link with New Goyden Pot that Sump 5 was explored, but unfortunately a boulder slope similar to that encountered in New Stream Sump was discovered, this time at only 30 ft. depth and some 90 ft. into the sump. This must be within feet of the upstream passage in New Goyden Pot discovered and explored by Alf Latham (NL.32:18).
R.J.S.
The Main Stream Passage extension found on 16th April, 1977 (NL.45:13) was surveyed to B.C.R.A. Grade 5.
Aim: to climb up into the roof tube between Main Stream sumps 2 and 3. Scaling poles were carried through the sumps and N.R. was poked up into the roof. Two possibilities were looked at, but the way on in each case was found to be silted up.
The Well: This was dived to see if any way off could be found apart from the suspected connection through to the sump in Cap Left Crawl. The passage off to Cap Left Crawl was located but was not forced as it became very low. Nothing else was found.
October Passage: A dive to investigate the "diminishing" air space at the end of October Passage. The sump is a very narrow rift with the roof dipping gently down. After 25 ft. of painful progress with no sign of the roof lifting a return was made. At the furthest point reached the floor had dropped down about 5 ft. and it was possible to stand up.
R.J.S.
Aim: to check main stream lines after winter flooding.
The sump 1 line was found to be OK but in sump 2 the lines had come adrift. The first section of 4 ft. now has no line. In the second and third sections, previously lined as one, the line had snapped and is now some ten feet short. No new lines were put in here, as the sump is easily done without a line by people who have been through previously. The third sump was found to be lined for 40 ft. only and so the remaining 50 ft. was replaccd and retied downstream. In sump 4 the line had broken but was not replaced as enough remains to act as a guide. The line in sump 5 had broken some 50 ft. in and had become entangled in the debris slope at -25 ft. This was untangled and belayed off to a handy bucket.
R.J.S.
Aim: to try and pass sump 5.
Both divers proceeded to sump 5 without incident and J.T.G. dived on into the sump alone. He tied on at the bucket at -25 ft. and proceeded to search the right hand side of the sump to try and find an alternative way on past the boulder slope found by R.J.S. on 16.4.77 (NL.45:13). Unfortunately no alternative could be found and J.T.G. tied off to a boulder after laying a further 30 ft. of line towards the boulder slope.
Aim: R.J.S. to have a try at sump 5.
J.T.G's. findings of 30th May were rapidly confirmed and R.J.S. soon found himself at the foot of the familiar boulder slope at -25 ft. Cautiously squeezing up between the roof and the large poised boulders he found that the passage enlarged suddenly in a flooded bedding at -15 ft. This was followed for 100 ft. to a second and less stable boulder pile. This was passed in the same way as before and a large lake air bell reached. After dekitting, a climb out of the water was found to lead to a roof bedding and inlet cascading in from a rift above. This was choked 10 ft further up. Back in the lake the way on was noted as an inviting sump at -8 ft. heading due south, but as he was unsure of the return the diver decided to devote his remaining air to getting back safely. It is not clear whether this is the air bell reached by Alf Latham from New Goyden Pot (NL.32:18) or not.
Aim: to dive sump 6 found on 23rd June
Both divers reached the air bell after sump 5 without incident and J.T.G. confirmed R.J.S's. finds of the 23rd. R.J.S. then dived into Sump 6 following the right hand wall. After 20 ft. the roof lowered over boulders and the way on consisted of a series of squeezes beneath ribs of rock between parallel joints. Unsure as to whether the easiest way had been followed the diver returned and tried following the left hand wall. Both this and a third attempt in the centre of the passage revealed similar results. The passage is about 15 ft. wide and extremely low and the slit leads one to suspect that it is not the correct route. It is possible that an alternative route exists in sump 5 bypassing the air bell. Discussions with Alf Latham have established that this is not the air bell he reached from New Goyden Pot (NL.32:18)
Aim: to resume exploration of New Stream Passage Sump by checking lines laid on 2nd to 30th March 1977 (NL.45:12).
The line was still in place at base and was followed to the base of the sump pool at -35 ft. unobstructed except for a few bundles of weed which were cleaned. In the continuation the line was found to have broken after 150 ft. and so fresh line was laid for 100 ft. to a section of old line which lasted for 50 ft. Short of air the diver returned to base.
Aim: to continue laying fresh line in New Stream
From the previous limit 50 ft. of new line was laid to some old line which lasted for 10 ft. Tying on again, 120 ft of new line was laid to the base of the boulder slope at which point the diver ran out of line. A quick look at the boulders revealed an inviting but unstable way on upwards.
Aim: to attempt to pass the boulder slope
The diver proceeded to the slope without incident and began tentatively to enlarge the route. Gradually gaining in confidence the diver continued digging for about 10 minutes with boulders and shingle cascading down in an amazing avalanche. Finally the route appeared to be large enough and the diver swam cautiously through keeping close to the roof. After about 10 ft he reached the top of the slope and emerged into a large flooded shaft with a shingle and boulder floor at -50 ft. and crystal clear visibility. Ascending slowly amidst confusing ribs of rock protruding from the sides of the shaft a halt was called at -20 ft. where the route appeared to narrow down and the diver got the impression that he had ascended on the wrong side of one of the flakes. Short on air and unsure as to the stability of the route back the diver hastily returned. In fact the route as engineered appears to be quite stable enough, as long as the diver is not too negatively weighted.
Aim: to check the lines in New Stream Sump and lay some thicker new line in preparation for an attempt to extend the sump.
Previous exploration: See NL.45:12, 49:16.
61m of thick line was laid into the sump from base. The old line, which was broken in several places, was removed.
Aim: to extend the sump.
A 152m line reel was taken into the sump and 91 m of new line laid from the limit of 4th July to the boulder slope. A few seconds of gardening and the diver was able to mole his way through into the shaft leading upwards. Unfortunately a large flake of rock has fallen down since last year and appears to be supported only by a piece of rather rotten-looking wood jammed across the passage a few metres up from the boulder floor. After examining the situation more closely the diver decided that he could not be sure as to the stability of the flake, which appears to be some 3 m long and divides the shaft roughly into two. It will be best to leave things to settle down after a few floods, before trying to squeeze past this obstacle. Most annoying !
Aim: to explore the undived Old Year Inlet Sump.
The sump starts as a promising looking pool, from which issues the stream which eventually feeds New Stream Passage. R.J.S. located the continuation as a small tunnel at -1.5 m depth. This was found to be body-sized and half full of silt which quickly blacked out all visibility. The tube was explored for only a few body-lengths and could be felt to continue with similar dimensions and no evidence of a breakthrough. A return was deemed to be prudent, as only a single valve was being used.
R.J.S.
Aim: to resume exploration of the downstream sumps (NL 49:15)
The large air bell between sumps 5 and 6 was soon reached. R.J.S. then dived into Sump 6, again following the right hand wall. This time he surfaced in a large low air bell after 12 m. The sump is low but quite easy. Sump 7 led off from the far side of the air bell. Following the left hand wall R.J.S. passed a tight squeeze to enter a rock floored bedding with minimal air space. Unsure of his return he turned back. Total length of dive approximately 15 m. The main stream sweeps over to the right in this sump in a low wide bedding. This was examined and was found to be impassably low after 15 m. Back in the air bell, though, a roof passage was noted. A climb of five metres led to a fine 2 x 1 m phreatic tube. After 80 m an area of cross rifts leading to static sumps was encountered. Just before this on the left another phreatic passage entered. This was followed for 50 m to a choke and small stream.
J.T.G.
Aim: to dive the static sumps found 28.9.80
Although there are a number of pools in the cross rifts, there appears to be only one proper sump. J.T.G. kitted up and dived. The sump started as a joint above a low bedding plane. The roof joint soon petered out and the diver was forced down into a low bedding covered in copious quantities of fine silt. After 30 m he surfaced in what appeared initially to be an air bell. Closer inspection though revealed a large streamway. Evidently the diver had blundered into the stream that runs from New Stream Sump in Goyden to Main Inlet in New Goyden. Upstream sumped immediately, while downstream 50 m of walking passage ended in a deep rift sump. The extensions were surveyed on the way out and predictably were found to head into the big blank area between Goyden and New Goyden. Exactly where we're not quite sure, as the compass we were using has subsequently been found to be of variable polarity. Plan opposite page 13.
J.T.G.
Aim: to dive the upstream sump of the extensions reported in NL.58:13. The upstream sump proved illusory and J.T.G. led through a 2 m. long duck into a large chamber with a lake as its floor. At the far end of this the bedding plane closed down and a rift in the floor led down to -6 m. This was followed in a northerly direction for 15 m before the way on was not apparent. R.J.S. also had a look at this and made another 3 m. of progress at a different level but again the way on was not obvious. The visibility was good throughout, indicating that we were still in the main flow and it may be that the main way on is through boulders in the floor.
J.T.G.
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