How deep are the pools on wipeout?

One pool looks like it's 16 feet deep, the pool with the spinning gyro, usually found in the second round. The individual stands are 10 feet high. That part looks shorter than the part in the water, so I estimate that the water may be 16 feet deep. For safety, the pools have to be at least 12 feet deep to break a 10 foot fall. I suspect that some pools are only 3 or 4 feet deep. The pool in the final round may also be 16 feet deep, to break the high jump falls. Safety has to play a role, like the public pools when it comes to falling in the water. That's my guess. Anyone else want to comment?