Akwa Dig Update, 8 June, 2002

Chuck Wilkinson works inside the cofferdam at Akwa Cave

It could be a wrap for the Akwa dig. We were very lucky this weekend to have a nexus of two critical components on hand and available to work. The first was Rick Orbin's hammer drill, which allowed us to set rebar into the bedrock. The second was Barry Horner's masonry experience, which we put to use on the cofferdam.

On Friday evening, Rick Orbin, Chuck Wilkerson and I hauled about 200 gallons of clay in five gallon buckets and dumped them in front of the coffer dam. This succeeded in filling the leak that was allowing the pond water to escape underneath the cofferdam's concrete foundation. We tamped everything tightly in to place and were pleased to see the water had risen noticeably by the next morning.

On Saturday we started early and by lunchtime Barry had set every cinder block available and used all of our cement in doing so. Hats off to Barry, he does very clean work. The landowner even said so. If the water rises to meet the new top of the cofferdam, we'll have succeeded in deepening the pond by two feet or so. At present, the pond is about 8 inches deeper than when we started.

A new challenge was realized however when the water levels rose to a certain point. Just as Tom Barton had suggested some weeks ago, the pond has begun to leak in a new location. We haven't located the leak precisely but did narrow it down to an area obscured with grass.

Clay in front of the cofferdam effectively stopped leaking water.

We hope that the leak will seal itself with silt in the next few days, but failing that we'll attempt a second clay patch and hope for the same success as before.

Finally we were prepared to push the cave and see where it would take us. With some effort we were able to push in to the top of a dome. Leaning out over the drop we could see a floor some distance below, and the sound of falling water was quite audible. This sound would turn out to be the water leak from the pond above, coming in via another route.

We rigged a rope to the haul point on my truck's frame. It then snaked its way into the entrance and to the top of the drop. At that point we rigged a redirect using rebar from our construction project. This worked nicely and helped hold the rope out of the narrowest part of the drop.

Barry Horner made short work of the cinder block part of the construction.

I was given the honors and suited up to do the drop. While the pit is fairly narrow at the top and could be chimneyed, it bells out farther down and required a descender to get safely to the bottom. I jumped on rope and slowly crept to the bottom, taking it all in as I went.

Once on the floor I asked Rick to lower one end of my survey tape and we measured the drop. From the redirect point to the floor of the pit was 32 feet. This would prove to be the longest distance in the cave.

The pit's floor plan is ellipsoid. A narrow lead at one end of the ellipse heads back toward the entrance and moves intermittent air. This is probably just air from the entrance above. A lead at the other end of the ellipse narrows down to a two-inch crack that bends out of sight. The sound of falling water (from the pond above) issues from that crevice. There was no discernable air movement in this lead.

View looking up from the floor of the Pit in Akwa Cave. Rick Orbin is visible at the top.

A final lead exists at floor level where the rope drops from the rig point above. A small drain takes the water that comes in the entrance and carries it down dip and away. It's a very small lead that didn't seem to have any real airflow or much potential.

Ever the surveyor I conducted a one man mapping session as I climbed the rope and returned to the entrance. We cleaned up our mess and calculated the material needed to raise the cofferdam to its desired height. If the pond stops leaking, we will raise the dam a little higher. But either way, it looks as if Akwa is a done deal.

The downstream drain at the bottom of the drop in Akwa Cave