Sal had been wanting to go down Wellgill for a while now with a
view to heading up stream and digging the shale fall to lower the water backed
up behind it. For a Sunday we started relatively early and were down by the
shaft top by around 10:30. The top was rigged and I abseiled down, followed by
Sal and Karli. On the way down the oxygen dropped sharply to the 18% mark at
the bottom, this was the same as a couple of years back, so no worries about
that. We headed upstream doing a duck walk - 600m of it, with the last 150m or
so being the lowest. Thankfully the level has one redeeming feature and that is
that there are joints in the arching where you can stand up straight every so
often.
After an period of time that felt like hours of back torture, but
really only probably around 25 minutes we exited the arching and into the
section of shale fall. The fall is about 50m long and the shale is the slabby
sort that tends to stay together and is easy to break up. We had a pick and a
folding shovel with us and we set to work making a channel that snaked over the
fall. Oxygen was 16%. An hour or so of digging soon made an impact and the
water was starting to flow more freely through the fall. We had lunch and noted
that oxygen was 14.5%. Once fed and watered we carried on with progressing the
channel, eventually having it running over the full length of the fall with the
water draining away quite happily. It was interesting to note that the oxygen
level went up as more water was drained. At first we thought that air might be
coming through, but that soon was put to bed and the explanation must have been
that oxygen was being released from the water as it flowed through the channel.
As a result of this it reached to just under 16%.
In all we lowered the
water level around 20cm, and we think that another 20cm can be achieved again
by deepening and widening the channel. Would this be enough to be able to go up
stream? With time getting on we packed up and headed back towards the shaft
bottom, not relishing the 600m duck walk, which turned out to be that little
bit harder now with more water in it. Karli prusikked up first, 7 minutes to do
60m - ahhhhh. I knew I was going to be much slower and so did Sal, we managed
around 20 minutes each. |
