pointless unless you know the exact sqftage
But close enough to come up with an answer.
Actually running the falls is where the most evaporation will take place, as much as 20-50 times or more then when the water stands still.
Think about it. When the water stands still, the air directly at the surface is saturated with the vapor. That limits the amount of water that can be lost do to evaporation. Kinda like putting a thermal blanket on a swimming pool.
Now, add either wind or water movement, and that blanket is now gone. Add a lot of churn like you would see in a large falls, and you have a tremendous amount of surface area, much higher than the actuall square footage. Might be as much as 3 times the surface area quoted above when you figure in the water that is saturated with bubbles. And all that air is not loaded with moisture, and is now taking water from the pond. Couple that with a slow wind of 15-25MPh and you have a tremendous amount of water being carried from the pond.
As for leaks in the falls, there would be signs of leaks, especially since it has been fairly dry over the last few weeks.
He was terrified at the sound of that type of loss. Bottom line is that the cost of the water per month will be about 15-18 dollars added to the current water bill.
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