Bamboo water wheel irrigating rice fields at Mai Chau

A bamboo water wheel is being used to irrigate rice fields at Mai Chau. The current of the stream turns the large wheel. Curved bamboo slats set at the circumference of the wheel lift water from the stream and, as the wheel turns, dump water into a bamboo pipe that leads to another field needing water.

Wet-rice farming requires that plants stand in water during early stages of their growth. The water then must be drained away before the rice fully ripens for harvesting. Bamboo wheels such as the one shown here aid this process of water management in places where the slope of the land does not allow good water movement to occur only with gravity and dykes that can be opened and closed for drainage between adjacent fields.