Every so often in the riverbed are little thatch huts housing water powered grinding wheels. They are communal property and well maintained.
Instead of a rolling wheel crushing the grain, a smaller, rough wheel spins horzontally over another similarly sized one. The top wheel has a hole in the center where grain is fed in from a hopper, and the ground meal comes out the side from between the two stones. This particular hut had two grinding wheels, one was grinding corn, the other rice. One family was grinding meal and enjoying the nice weather while the water did their work.