1st stage free flow

I was planning to do a multiple stage, solo dive push to possibly explore some new passage in the Luraville Spring system. I went this dive alone cause of the nature of this system. There are many low nasty spots that are always blasted out, so I preferred not to have somebody else in my wake. I had made a set up dive the previous day putting two stage bottles below the Escape Hatch. I had done this because the Escape Hatch requires negotiating two major restrictions that tanks must be removed to pass through. The Hatch is a sinkhole entrance, so I had entered from closest downstream entrance and placed the bottles in the main passage just after the restrictions.

I started my dive through the Hatch so that I would cut off 1200' of passage, which I would have had to swim coming from the closest downstream entrance. I picked up my two stages and started off the first one. Luraville Spring has a floor covered with fine silt and clay, so when I dropped my stages, I had no choice but to place them gently in this muck. I went on switching to my primary sidemount bottles. I didn't find any new passage to explore, and turned around on thirds to come out. There is not a substantial flow, so I used almost the second third on the way back. When I picked up the first stage, there was considerable silt and clay inside the first stage of the regulator and it had gotten lodged around the diaphragm. This caused the regulator to freeflow from the first stage, which most divers had never even heard of. I still had over 2/3's left in this stage bottle, so I decided to breathe from the 1st stage instead of heading into the reserve in my primary bottles. If my last stage bottle would also fail, I preferred to have this extra reserve for that possible situation. Also, there is still plenty of air in this malfunctioning tank, I wanted to try and use it first. I turned the tank valve on and off and breathed from the first stage. This was not the most comforting situation to be in, so I sped up as fast as I could go, which is not easy to do in a cave that is only 5' tall in spots. I got back to my next stage bottle and quickly got onto it. Luckily this one was working properly and I continued my way out of the cave with no other problems.

My lesson for this dive was to install cold water/environmental kits on all my first stages to keep debris away from the spring and diaphragm.