The simple law of gravity means if you take your water bottle and pour it out, the water will fall to the ground, right?
Not always, no.
Let’s just say you’re a tourist at Hoover Dam. Let’s just say you decide to empty your water bottle out into the dam below. What happens next is rather curious, is it not?
So how does this happen? Leslie Hutchings, who posted the first video to her Instagram feed, explained that it’s the updraft from the dam below that causes the water from her bottle to flow upwards instead of down. When the wind hits the wall of the dam (pictured below), it needs somewhere to go and moves up.