Another issue... is a pool this deep feasible? I've never heard of a pool being much deeper than 20 feet or so (NASA has a deep pool for weightless training) other than the HMS Dolphin. I have done a number of google searches looking for other deep pools and found nothing. I can't think of any reason actually building the pool wouldn't be possible. Actually lining the shaft to prevent leaks might be hard though. How wide were you thinking this deep area would be? And what about insurance?
I've dreamed about a pool like this too. If you ever get it completed, you'd better invite us all out for a BBQ.
