The "diving board with handrails all around" is north of the airport terminal. There are actually two of them, side by side, with splendid views into Pueblo Canyon. I've wondered for years about the origins of these "viewing platforms and what they were used for.
The "storm drain pipe from airport fence into Pueblo Canyon" is actually part of the trail, i.e., you have to step across the very top of it. There is a wooden fence at this very steep drop off along the trail. I always admire the steep way down but don't think I'll take it.