Pushing upstream and downstream Elk River

I know I’ve skipped a couple of trips on here, including some nice photos from Scrubby Creek and Shade of Death. However the excitement of the Elk push dives this weekend is going to post first and I will have to get back to the Scrubby Creek shots for you at a later date. The Elk project has been going on for just over two years now and it seems that at times we’ve been making a lot of effort for very little progress. This weekend we put in a lot of effort and got great new cave in return.

It was a three day weekend in Victoria so we planned for an easy day Saturday, a downstream push on Sunday and then a clean up day on Monday. The proposal for the “easy day” was to carry in the gear in preparation for Sunday and then go and have a quick look at the upstream sumps. I hadn’t previously dived upstream and from descriptions it sounded both relatively short and had stalactites. This was a good enough reason to drag the real camera through for some piccies without the pain of taking it downstream.

The three of us headed upstream together. I was only using 3L tanks while Ken and Steve were on 7Ls and 5Ls respectively. The low, flat, shallow passage took some difficult manoeuvring of the camera and I was glad not to be lumping large tanks as well. The photos from here are deceptive – while the water was clear, it was only clear very briefly. Even the ripples from our movement through the water would disturb the silt on the walls ahead of us. As I turned to take photos of Ken I was looking at the camera through a cloud of silt. In most cases I was shooting blind and hoping there was clear water in front of the dome.

The shimmering “surface” above in the top photo is also a lie as you can see by the angle of Ken’s head. In most cases this is less than an inch of air pooled against the roof. I was relatively buoyant and none of us was wearing fins, so it wasn’t the most elegant progression down the passage. After the first short sump and a second long sump we reached an airspace with some nice decorations. I dropped my tanks and we had a short photo session before I left Ken and Steve to continue into the third sump.

As it turned out I should have continued, because they reached the end of the line and then the end of the cave very shortly after. The upstream low flat passage turned into a series of rimstone pools progressing upwards. After some difficult wriggling over limestone they emerged into a large aven with an estimated 7m height. The water in the passage was coming from a hole about half way up the aven in a waterfall. With sheer sides getting up there is going to be a bit of a mission so they surveyed their way home. The discovery is interesting because we’re not aware of any surface features in that area that may correspond to the aven underground.

It was a slightly longer day than anticipated but we were still back at Homeleigh by 9pm. On Sunday morning we were getting changed at the Potholes Carpark when we took a short break to corral three escapee horses back into a paddock. After that excitement we were in the cave by 10.30am and headed straight for the end. For this trip we were carrying two 9L carbon fibre tanks and I had the small camera. The intention was to put Steve in sump 7 with the two 7L steel tanks that were already in the cave. We also carried in another 6 lumps of lead to weigh the carbon fibre tanks down with.

Along the way we dropped two of Ken Smith’s famous pingers into sumps 3 and 4. The one in sump 3 was located by the dry support team and found to be within 2m of the estimated surveyed location, which is a great credit to the survey work done by those who came before and Peter’s mapping work. The pinger in sump 4 was sitting under 115m of rock cover and very close to the fenceline around the Potholes Reserve. The rock depth at the edge of pinging range and the electric fenceline interference made detection impossible, so we were unable to confirm the position of sump 4 against the survey.

The trip was uneventful and after spending five very chilly hours shivering at the edge of sump 5 I watched Steve re-emerge triumphant. After laying a further 110m of line underwater he surfaced into a small chamber. Crawling forward wearing four tanks, the small chamber became a very large chamber. Steve ditched the tanks and headed forward to explore and survey. Several waterfalls to be down climbed indicate that sump 7 is still perched and not yet at the level of the Murrindal River. The estimated drop across the chamber is 20m. At the far end there was a small pool which presumably leads into sump 8.

With time ticking by Steve surveyed the chamber to reveal a total length of 145m. He then headed out and the three of us carried four tanks back to Uncle’s Aven, to emerge at 2.30am. With our adventurous morning persuading horses off the highway the chamber has been named The Hall of the Crazy Horse. And now we have some time to plan the next expedition and work out how we’re going to get multiple people through sump 7 to support a dive into sump 8. Huge thanks to all of those who helped out both this weekend and along the way so far. Without a very large number of helping hands these push dives would be impossible and your help is deeply appreciated.