Val,
It's been a while, (about 23 years) but as I recall the piers at Des Sub piers Norfolk, Va. were about ten feet above the water.
The pier, on my modules, usually has a 137' coastal freighter moored alongside, and it's 6' above high water.
Over in Waukegan, the sea wall, where the gypsum freighters moor to unload, is about 5' above water level.
Tyson's point is probably the best, set your tanker "in" the water, and see where the pier should be to look the best. There is no fixed, or standard height for a pier.
Now, for a truly "educated" guess.....sail an iceboat past the pier, shoot a radar range to determine your distance from the pier, with a sextant, shoot the angle to the top of the pier, and using trigonometry determine the height, then add the distance from the surface of the ice to eye level when the angle was taken, and you'll have the true height of the pier.
Of course, after that smart *** answer, you'll probably opt for the "one shot altimeter" approach, where you push me off the pier, record the time it takes for me to hit the ice, and then using the formula for the acceleration of gravity, you can determine the height of the pier.
