Irrigation
Farmers start moving water to the crop instead of moving the crop to the water.
- When
- Known to
- ± 500 years
- Era
- Neolithic, Holocene
Simple canal irrigation appears in Mesopotamia and the Zagros foothills by the sixth millennium BCE, allowing cultivation of land that rainfall alone cannot support. It is the technology that opens the southern Mesopotamian alluvium — extraordinarily fertile, almost rainless — and it changes society as much as agriculture: canals must be dug and maintained collectively, water must be allocated, and disputes must be settled. Irrigated land also salinises, which is a slow poison to the systems built on it.