[boccaff]

TL;DR, simpler mechanics for the irrigation system.

The circular pattern comes from the area irrigated by the simplest configuration of a center-pivot [0], which is a fixed point in the center to access water. "Non-circular" area require linear/lateral movement "center-pivots" that require a way more complex control system, or some kind of booster to cover the "corners of a square".

[0] https://en.wikipedia.org/wiki/Center_pivot_irrigation

[aivisol]

I think this is not what parent asked. The question was why circles are arranged in square grids but not in haxagons. Which is great question, and I would like to know the answer too.

[wiredfool]

I suspect it's because the land ownership is mostly rectangles, as are the adjoining roads.

[danuker]

The "circular" is clear. But the "square grid" part is not. Why are the circles arranged in a square grid instead of a hexagonal one? Is it property definition difficulty?