The savannah villages unique feature of having extra farmland poses quite the issue whenever the terrain is not perfectly flat. A water source is often left exposed, which destroys the farmland and creates burdensome waterfalls. Additionally, water will not move when it should upon generation, as shown in one of the two images, though I believe that is a seperate bug entirely.

To reproduce, simply go a savannah village and look for this issue, as it occurs in nearly every single one.