Heartened by the discovery of Smegmire Pot (1) various members of the club stepped up their search for an entrance to the system that lies beyond the ends of Redmire and Smegmire pots. It soon became obvious that there was little chance of finding another top entrance, partly due to the lack of major stream sinks, and partly due to the poor landowner/caver relations in the area which really precluded digging on a large scale. In view of this, Rob Shackleton suggested an exploratory dive in Birks Wood Cave, the resurgence for the system.

This was accomplished on 25th April 1976 with the aid of Bob Mathews. Rob dived at the end of the canal parallel to the main streamway (2) and passed a constricted 10m sump to a very small airbell. Snagging of the base fed line forced a retreat but a return was made on 7th May when, on a solo trip, Rob passed another constricted sump of 5m to a large airbell and a further sump of 12m. The inviting trickle of the streamway brought visions of a walking sized streamway, but the appearance of another sump restored perspective. This sump (sump 4) was dived a couple of days later and revealed 20m of rather desperate underwater passage to an airbell and a tight squeeze through which could be seen a larger airbell. A visit was paid the following weekend, but the arrival of a flood pulse led to a rapid retreat from the cave.

It was decided that a further trip was needed to investigate the possibilities of the airspace beyond sump 4, so on 19th June Rob, accompanied this time by Julian Griffiths dived through to sump 4. Rob proceeded into the sump but was brought to an abrupt halt when a boulder fell out of the roof onto him. Thoroughly disillusioned with the tightness and instability of the place, the line was pulled out and the pair returned to sump 3. Before going out though, Julian had a look at the rift off to one side of the streamway between sumps 3 and 4. Much to his surprise, it went: a rather tight abandoned streamway was followed for 60m to a 5m drop down to sump. Elated by their discovery, the pair exited, making arrangements to return the following weekend with a smaller bottle.

The task of dragging the bottle up to this next sump (sump 4A) proved rather arduous as the dimensions of the bypass are not generous. However, Rob dived the sump and surfaced after 25m at the bottom of a 5m climb up to a similar deserted streamway. This he followed for about 75m, meeting the main streamway again in the process. Another sump (sump 6) lay ahead: no belay could be found for the line so a return was made. Not surprisingly, Rob and Julian were back in Birks Wood the following weekend, having borrowed another 15 cubic foot bottle. Both reached sump 6, which was emitting loud glooping noises in the very low water conditions. It turned out to be a low free dive of just over one metre. On the other side, the streamway came trickling out of a high narrow rift passage. Diving gear was quickly abandoned, the cave had at last gone 'big'. First impressions of the Birks Wood Cave system were not favourable: 100m of tight streamway being followed by some tight and awkward rift passage. 150m from sump 6 though, the cave relented a little and 300m of varied streamway led to the base of a 10m pitch. This was freeclimbed and the stream passage at the top followed for about 30m before a decision was made to turn back.

Due to a dearth of 15 cubic fortnights foot bottles and a holiday in Ireland, it was not until the end of August that another visit was paid to the cave. This time Rob, Julian and Andy Nichols all reached the previous limit of exploration, a ladder being rigged on the 10m pitch to ensure that it would be passable in wetter conditions. Beyond, the streamway soon developed into a low canal passage with 30cm of water, 60cm of air. This continued for about 100m until a sump was reached. A cursory inspection revealed a duck off to one side, but after only 10m, this again sumped. The appearance of this sump was rather surprising in view of the fact that it is 600m from and 45m above sump 6. Fortunately, however, the sound of falling water could be heard from through the sump, but no usable airspace could be detected so an exit was made.

Two weekends later Rob, accompanied by Julian, passed this sump (sump 7, a 5m freedive). On the other side a low crawl led to the base of a boulder choke. Climbing up through this, a large chamber was entered with the stream coming down a 10m waterfall. As this was clearly not freeclimbable, the pair surveyed their way out, surfacing early on Sunday morning after 14 hrs underground. The general waterlevel was much higher on this trip and the bedding plane crawls between sumps 5 and 6 were largely full of water. This necessitated another half metre sump and a 6m duck. It is obvious that this section of passage floods readily in wet weather.

To date no attempt has been made on the final waterfall. Events at Ribblehead occasioned a switch away from Wharfdale and there has been a natural reluctance to return - the proximity of the caves to the road and catering and accomodation provided by Jack and Muff at Sphagnum Nook (Winshaw Gill) are very persuasive factors in Ribblehead's favour, nevertheless there remains over 2000 feet to be discovered in Birks Wood leading up to Redmire. Climbing the thirty foot pitch will be a fairly strenuous proposition - apart from the strenuous nature of the trip up there, one cannot relish the thought of bolting in such a wet and windswept place. However there seems no reason why this passage should not be negotiable, and a through trip could well be something more than a pipe dream.

Hydrology

The Birks Wood system or Redmire system (as it has been more usually referred to) has long been predicted. Dye tests by the CPC on the Redmire stream in the late 1960s established that Redmire went to Birks Wood rather than to Birks Fell and that hence a system parallel to and to the South West of Birks Fell Pot must exist. The discoveries outlined above have merely confirmed this.

In any description of the cave one is naturally led to compare it with Birks Fell. Both are essentially long streamways formed along a single joint line, Birks Wood being far tighter than Birks Fell due to its smaller surface catchment area. Nevertheless, in both caves, high rift passages predominate. The main difference is that whereas Birks Fell cuts down through a shale band in its lower reaches (below Elbow Bend), Birks Wood resurges on it. In this sense, Birks Wood can be directly associated with Hermits Cave, the old resurgence for Birks Fell Cave, which also lies on the shale band.

The two main inlets to the system are Smegmire and Redmire pots. Redmire itself is fed by two surface streams, one entering just past the entrance crawl, the other below the pitch. The latter is one of the two sinks that lie between Redmire and Smegmire. The second sink must enter Redmire in or beyond the sump. Smegmire, as Redmire, has two inlets. One is met at the bottom of the entrance climb and corresponds to the sink about 20m upfell from the entrance. The second is in a shallow valley along the fell towards Firth Gill and appears through the roof towards the end of the cave.

There are no other major sinks between this last sink and Firth Gill that feed the system. However, about 20m along the fell from this sink lies a shakehole aptly referred to as Quagmire in view of the large quantities of mud present. Hammering and voices at the end of Smegmire can clearly be heard in this shakehole and it is probable that Quagmire lies slightly beyond the final choke in Smegmire. Some desultory digging was done, but conditions were far from ideal and when Birks Wood was extended, the dig was abandoned. It has since collapsed and been filled in. If a concerted dig were possible at this point it might provide a top entrance to the Birks Wood system.

Note.

This is by way of being a preliminary article on the Birks Wood system. It is hoped that a period of drier weather will allow a continuation of exploration and the completion of the survey. As it stands, Birks Wood can rightly take its place among the major systems in Wharfedale. Constituting one of the most consistently awkward caves in the area, its length approaches 1000m, with the possibility of a mile of passage in all.

Julian Griffiths

References:

1. Cambridge Underground 1976 pp 34-6
2. Craven Pothole Club Journal 1971
also CDG Newsletters No. 40 July 1976 No. 41 October 1976