Cueva de la Marniosa – Terminal Sump 2 dive

Gareth had been having trouble sleeping over the few days previously, possibly due to the heat. This meant going on a push trip to the end of Cueva Marniosa to the Terminal Sump 2 would not be sensible. Josh was still determined to go but was not keen on the idea of a solo trip to the end (with or without dive kit), based on various reports of the cave suggesting a hard trip was in order (see reports from Boothroyd et al.). Therefore Josh persuaded Arwel to join him since Arwel, despite not being a cave diver, had previously passed Sump 1 without issues to help Gareth in the 80m aven beyond. Thankfully Arwel agreed and an uneventful trip down to Sump 1 was had in good time (45 mins) where both dived through, Josh carrying a bag with SRT kits plus other bits and bobs in a Daren drum (floaty!). On the other side Arwel started to brew a hot chocolate whilst Josh sorted equipment for the Sump 2 dive, including a makeshift dive harness (etriers), a single full 3L cylinder (one of two left on that side of Sump 1 by Josh two days prior), some bolting kit and general dive accessories.

The journey down to the limit explored by Josh on a solo trip two days before was much nicer this time, with company, and the obstacle turned out to be an awkward squeeze between a fallen block and the passage wall (which Arwel climbed on the way back, whereas Josh squeezed back up). After this, relatively pleasant stream passage with the usual climbing, traversing, rifts and stooping was followed for some time, via some large chambers, passing a sump pitch to the left noted on the survey, to the 14m pitch into the “bear pit” obstacle. This area had been the site of frustration for multiple previous explorers, as evidenced by equipment left behind, including Brian Judd’s lead and diving cylinders. Multiple lengths of rope were left on or near the pitch, and the first attempt to descend by Josh was shaken by one of the Y-hang “anchors” failing, when a natural rock flake inconveniently broke away. During the subsequent fall/swing encountered by Josh, an impact onto an extended left arm caused some pain and aches for the remainder of the trip. The anchors were re-rigged and the pitch descended into a large resurging pool, likely the regained streamway after it is lost in one of the aforementioned chambers. A swim across this and a short section of walking passage lead to a tight rift and a climb above.

This area is not well represented on the survey, no climb is specified in this large walking section however having communicated with MadPhil Rowsell previously, who had bolted up this climb, Josh was aware that a rope should be nearby. This was found to be about 4m up, anchored to a bolt. Josh went back to cut a short section of excess rope from the bottom of the previous pitch before Arwel, being by far the better climber, clipped it onto the 4m bolt and continued up, carefully, to the top. Midway AR found another rope from across the void attached to the rope he was climbing, which turned out to be the main hang rope installed by MadPhil for the pitch after climbing the corner. This ascending pitch is around the same height as the previous descending pitch (15m or so) and is not on the survey, despite having been climbed by the 80’s explorers (dive line was found above and below the pitch).

There are a couple of ways on at the top, and given the inconsistency of multiple descriptions a long while was spent looking around for what matched the descriptions and survey best. A retreat to the bottom of the pitch to explore the rifts below was carried out, to cover all routes, until after a discussion on whether to continue or not, it was decided to choose the ongoing large passage at the top (which didn’t match survey direction or description). This continued into sharp, snaggy, nasty traversing at high level and became obvious that it was the way, where there was no possibility of staying at the same height, with lots of up and down climbing on extremely weak and sharp rock (a fall would NOT be conducive to life). A point high up, on an S-bend was reached where progress began to look bleak and dangerous. More discussions were had where Arwel seemed happy to turn around, with Josh agreeing subject to one more attempt to bottom the rift. This turned out to be fruitful, where an exposed, cautious, but relatively straight-forward series of descents led to rifted streamway and eventually the difficult, tight, friable jagged rifts that were expected based on prior reports.

With the bag of dive gear, the journey through this rift had to be methodical, slow and careful. Everything snagged, at all levels, with multiple restricted and resistive climbs up and down, chest-tight squeezes and a deep pool midway through, requiring a cold swim across. Finally the rift widened slightly, leading to a boulder choke (easily passed) and more pleasant streamway. This got appreciably easier until stomping streamway lead off, with periodic obstacles, to the final chamber with the large, clear blue Terminal Sump 2 at the far end.

Without wanting to waste time, Josh kitted up into his dive kit and entered the water, buoyant, using two compact reels (i.e. search reels) as dive line. The crystal clear underwater passage dipped gradually down to a shallow 5m depth, where it continued to an elbow. Surface was visible ahead and was reached after approximately 25-30m, using both reels with only a metre to spare to tie off on the far side. Approximately 40m of open, lightly cascading stream passage was explored, after removing some kit, to a calcite/mud climb on the right and rifted stream passage on the left. The climb was pushed until it became too exposed for the divers’ situation, but was seen to choke ahead. Down on the left, a very short foray into the narrow stream passage saw an ongoing rift continuation, relatively pleasant with no sign on an imminent sump. Aware that Arwel was waiting on the far side and would be getting cold/feeling isolated, Josh began a return. The security of the join between the two line sections was inspected once more, in doing so, due to very positive buoyancy, Josh found himself stood upside down near the far side of the elbow of the sump with feet on the roof and head on the gravel bottom – an amusing situation in such a place. The line was left in place, and an exit was made to a pleased Arwel.

The trip back to Sump 1 was a long, uneventful journey, where Arwel got a brew on and heated some ration packs, while Josh prepped all kit for bringing back through the sump (it was at the time improbable that either Gareth or Arwel would return with Josh to Sump 2, hence all kit was due to exit from the diver-only section of the cave). This included all kit used to aid the aven downstream, plus cooking and excess dive kit. This amounted to three large bags for Josh to exit with, which were tied together and made as neutral as possible for the return, which was successful and unhindered. AR being uncomfortable in deep canals (which are extensive on the exit side of Sump 1) continued through after the dive to warm up at the dryer Sump 1 dive base, whilst Josh ferried the remainder of kit through the canal and up the cascade to meet him. Kit was then sorted, a brew was heated, and a further uneventful exit was made, reaching the surface 16 hours after entering the cave (at least 12 of which beyond Sump 1). Thanks to Arwel for enduring yet another Marniosa Sump 1 cave dive!