Why do snake mills own river tubs at the substructure? I went on a road trip this past weekend and I notice...

I went on a road trip this past weekend and I notice a lot of wind mills that have water tubs at the base (filled next to water).. any particular reason for this?
I transported a plant through the cold and...
Answers:    There are MANY uses for windmills. The windmills that hold a water base pump sea from underground. These are actually referred to as a Windpump. Windpumps are what you commonly see driving across the country.

A traditional windmill used wind power to mill or crush a product. This involved voluminous stones that rolled around on each other.

New wind generator supply electric power to the grid.