Easegill Hydrology

Posted by Swaledale Outdoor Club on 2009-10-04

John G and I met in Bernies with a few ideas and a selection of ropes in the car. I’d been carefully studying various web sites for the previous few days, trying to anticipate how much rain was likely to fall overnight prior to the trip. There was reasonable consistency at around 3mm.

On the drive over to Ingleton I’d already ruled out Sell Gill wet route and Top Sink as the streams were gushing off the higher fells. Local reports were that it had been ‘quite wet’ during the night. We agreed on a pull through Pool Sink and set off for the cave. We got a good drenching on the walk over and noted that there was quite a lot of surface water, but that the peat (which had dried out over the preceding month) had absorbed very little.

We descended to the dry stream bed at County Pot. I was surprised to see the stream running a short distance upstream of County, but apparently sinking. Strange, I thought, I didn’t know there was a sink there. Suddenly it dawned; we had arrived just as the flood pulse was making its way downstream. This was something I’ve wanted to observe for a long time, but it was completely unexpected. We watched as the leading edge worked its way downstream over the dry rocks; the flow behind it steadily increasing. It was a fairly gentle spectacle, but amazing to watch.

We continued upstream and within a few minutes the stream was in spate and we were both silently assessing the wisdom of a Pool Sink descent. The normally dry entrances to Corner Sink and Slit Sinks were swallowing large volumes. When we arrived at Pool Sink the pool was full with the level just a few inches below the entrance. The main inlet is in the stream bed further upstream and would be taking a huge flow, so we had a rethink. We decided to return downstream and follow the pulse. It had made it as far as the deep pool at Cow Dubs. This was slowly rising, but it would take a while to overflow, so our thoughts returned to underground.
 

We met another group who had just rigged the County pitch, asked if we could use their ladder and decided to follow the Manchester Bypass to Stop Pot. On the way we took the very low crawl to Carrot Chamber and enjoyed the formations

We found the route to Holbeck Junction negotiable (keeping a little higher than normal in a couple of places) and then investigated the lower reaches of Pool Sink as far as Spiral Staircase Passage via high level routes in Green and Smelly Passage. This repeated some of the ground John and I had explored many years previously when trying to make sense of the survey in this complex area and finding the connection with the Borehole (not an option today with a powerful flow gushing out of it).
 
On our return we visited Straw Chamber and the passages beyond (john pointing out a couple more Easegill links), and then took the Four Ways Chamber route to Wretched Rabbit Passage and the surface. The stream had subsided slightly and the sky was clearing for the return walk. To quote John; “A most satisfactory way of spending an afternoon.”

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