Somebody help me visualize what 400GPM would like like.

Would a 4" diameter hose running a solid stream of water be accurate? 6" hose?

I'm envisioning about (8) 55 Gallon drums being filled, or emptied, in a minute.

Excerpt from Robert Crais' "The Monkey's Raincoat:"
"She took another microscopic bite of her sandwich, then pushed it away. Maybe she absorbed nutrients from her surroundings."