[mlhpdx]

What’s large? I’m not sure the creeks and swimming holes I frequented in my youth would qualify.

Also, the post isn’t about swimmable water—it’s a cautionary tale about how little it takes to drown. I can confirm that as one winter my neighbor drown in a shallow mud puddle off his back porch. He had a non-fatal heart attack and fell into it unconscious.

[kulahan]

Large is exactly 20910 liters or more per square foot, absolute cutoff, and if you go even one under it's no longer large.