This photo was taken in 2008, and shows Joyce Lundberg entering a deep pool in the main Deer Cave stream. This was the only place in the cave where we really had to get wet much above the knees.
Of note, this photo was taken about 400 meters from the rear entrance to the cave as seen in the background (that's a quarter mile away!).
And, we were there, in this fantastic giant cave, to do some science. If you have an interest in stromatolites, then you should read about what we discovered and learned about such from the trip at:
Sorry this is not the whole article, but the abstract does give a lot of details.