The amount of PSI that it takes to raise 1 foot of water is 0.433 PSI.
In every foot of water there are around 0.433 lbs per square inch or psi of pressure.
The reason there is around 0.433 pounds per square inch or psi in every foot of water is due to the eight of the water column that is above a given point.
Water also weighs around 62.4 lbs per cubic foot.
At sea level, the atmospheric pressure is around 14.7 psi.
So at 1 foot deep, the total pressure would be 14.7 + 0.433 which equals 15.133 psi.
In order to find out the pressure that is exerted by a column of water, you divide the weight of the water by the area that it's acting on.
So because we're looking at pressure per square inch or psi, you would divide the weight per cubic foot by the number of square inches in a square foot (144).
And for every additional foot of depth of the water you add another 0.433 psi to the total pressure.