Once you're talking volume, things start scaling cubicly. It's not intuitive to most people that a cubic meter of water weights a ton. It's certainly not intuit

Once you're talking volume, things start scaling cubicly. It's not intuitive to most people that a cubic meter of water weights a ton. It's certainly not intuitive how to compare say, the Hoover Dam to a 7.5km long (but skinny) reservoir. This massive reservoir could be about 50 by 50 by 50 meters. Or 10 meters deep, and 120 meters square. Which is in a lot of water, in a sense. But compared to the Hoover Dam, which is 2,600,000 cu of concrete (and about about 300 million times the capacity of the Japanese reservoir, if you're including Lake Mead) it's not very big. Note - I might have made a huge mistake somewhere here. It's hard to tell when you start cubing things, because intuition starts breaking down.