Thanks for the notification.
I had figured that the sumps between the downstream end of upstream BPoW and the upstream end of the downstream section of the cave would be open after the prolonged dry spell we?ve had, so had planned to go there and check them out. Saturday (6/5) we set off down, via the two scrappy little pitches that take you to Long Gallery and then to the stream, where a bit of easy hands and knees crawling leads to the first sump. Sure enough, when we reached the first sump (am I right here; are there two sumps, or is it one with an air-bell?) it was totally dry, a phreatic tube about 1.2 m in diameter that dips a bit (as you would expect). After a few metres you come to the second sump (or second part of the only sump), but here there is a ~3 m slope to descend before you encounter another ~1.2 m diameter tube. Obviously the floor here can?t be solid rock ? unless there are tiny cracks and fissures that can only transmit a small amount of water ? I think that the downstream passage must be maybe 4 m tall, but crammed with rubble of one sort or another (see diagram below). On Saturday there was not quite enough water left to come over the top of one?s wellies.
Anyway, once through the sump(s) we continued to the upstream sump and out via the Gour Chamber, to complete an entertaining little round trip tha?ts only possible in dry weather (for mere mortals).
Here are some snaps:
The 'first sump' encountered:
BPoW 'first sump' encountered by
John Forder, on Flickr
The second sump:
BPoW 'second sump' encountered' by
John Forder, on Flickr
Schematic diagram:
BPoW Sumps schematic by
John Forder, on Flickr
I see the last one has been truncated ? there should be a bit more on the right.