The area that I usually hunt is about a 200 foot stretch of river (the river is probably 10-20 feet wide in most places). It ranges anywhere from 3 inches to 5 feet or so, and has a decent current. I'd say average depth is 2 feet, and my preferred depth is 2-3 feet.
I like rivers because I need no tools. I just hold my detector by the shaft, about a foot or two from the coil, and lay down and swing, digging all repeatable tones (I set iron disc to 40 and turn on iron audio on my AT Pro). I use my hand as a fan to kick up dirt and the current carries the dirt and rocks away. It works pretty quickly and I can usually retrieve targets in 10 seconds or less.
I was thinking next year that I would pick up a second propointer and waterproof my current one, and also make myself some kind of pick to help get through some of the rocky areas.
edit: forgot to say I use a mask + dry snorkel and the waterproof headphones.