SILT HAPPENS - 2/15/2000

I tell this story in hope that it will enlighten divers not to make the same mistakes that I have experienced in my diving adventures.

It was a sunny spring morning that I learned many valuable lessons which have nourished my diving education. A perfect day for diving, the temperature was in the mid 80’s with no bugs, the weather dry, so the long dirt roads to The Nest were in good condition for a welcome change. The basin of the 200’ diameter pond was crystal clear.

Bob and I had made our plans for a leisurely scooter dive in an offshoot tunnel of the downstream section of Eagle’s Nest. We descended to 30’ where we hung our oxygen cylinders on the tree in the basin before dropping through the vertical entry that opens into the main ballroom. Descending down the line, we hit the top of the debris cone at 125’, which was our drop for Nitrox cylinders. After clipping the cylinders to the line, we trimmed out on our scooters and headed west to the downstream tunnel. During this scooter dive, Bob and I received an education on the need of redundant buoyancy and the need for a less narcotic gas for our chosen depth.

About eight minutes into the dive, at a depth of 230’,  I looked back just in time to see Bob and his scooter plummet into the silt floor. I was only about 20’ ahead of him, but before I could reach him, the silt from his impact had zeroed the visibility. The guideline I had to follow ran near the ceiling, which was about 10’ off the floor. Fortunately, Bob went down directly under the line, and I was able to quickly locate him from his bubbles. I descended down the bubble trail to find him buried in silt so deep he couldn’t find the bottom. Bob had pulled the corrugated hose from the bladder of his BC, and was waving it, when I got to him, to show me what had happened.

At this time, I should fill you in on a few details. He was wearing one single-bladder BC, a wetsuit, and double 104 cylinders. He also had a negative scooter attached to him, and was breathing air at 230’. After not being able to repair the BC, I had him unclip his scooter and hold onto me as I fully inflated my drysuit and BC. This was just barely enough lift to get us out of the silt. We ascended to the ceiling and relocated the guideline. Holding Bob by his manifold with one hand,  I was able to trigger my scooter with the other to literally "drag" us out of the silt-out. It wasn’t long before I realized that we had another problem.

With all the distraction, I had picked up the guideline in the prop of my scooter. By this time, I had gotten Bob to clear water and somewhat stable bottom, so I signaled him to exit in front of me while I pulled the line from the prop. Bob exited in front of me, and I rejoined him at the mound. Luckily ,at this time, we had 3/8" rope as a downline from the tree in the basin to the top of the debris cone. The heavy rope was a welcome site and assisted in our ascent from the cave. Upon surfacing, Bob made several generous offers of his gratitude which I promptly rejected. However, the following day, after further consideration, I approached Bob about these generous offers only to find that they had been rescinded.

The following day I returned and recovered the abandoned scooter. Approaching the crash scene, I could only see about six inches of the shroud of a six foot scooter sticking out of the silt. The extraction from its burial site in the cave proved uneventful. If you get the opportunity to dive the downstream tunnel, the remnants of "The Trench" are still visible today.

The first lesson we learned was the need for redundant buoyancy control devices at depth. The second lesson was the need for a less narcotic breathing mixture. At that time, helium and decompression tables were not readily available. With advances in today’s diving technology, and mixed gas availability, it is not practical or safe to dive air at that depth. I’ve always said, "You can get away with a multitude of sins until something happens". This incident could have very easily led to tragic results for both of us.