When one speaks of inches of water column, the diameter of that water column doesn’t really matter, does it? If P = pgh (where p=density) and P = F/A, then because pressure is per unit area…the diameter of that water coumn doesn’t matter, right?
So, whether a 5-ft column of water in a pipe or 5-ft column of water in a 55-gal drum, the water pressure at the bottom is the same, correct? (Note: 1 psi = 2.31 ft x 12 in/ft = 27.72 in)
I saw a mill pond in Connecticut a few years back where the damn had been modified to make the reservoir a bit deeper. On a 50 foot wide dam, they ran a string of 2X10’s flat across the top, bolted them on, and nailed some more 2X10"s perpendicular to the first set. It worked. The pond was hundreds of feet long.