Angkor Hydraulic System

Timeline

1. c. 800–1000Plains surrounding the Tonlé Sap · CambodiaKhmer rulers began building barays (artificial reservoirs) and feeder canals on the Angkor plain, converting seasonal floods into controllable irrigation water and supporting the expansion of the early capital.
2. c. 1100–1200Around Angkor Thom · CambodiaMonarchs such as Jayavarman VII expanded the East and West Barays and a complex canal network; the hydraulic system reached its peak in scale and organizational capacity, supporting settlements of up to a million people and large-scale temple construction.
3. c. 1261–1270Hydraulic installations in the Angkor region · CambodiaDuring the reign of Jayavarman VIII, the empire continued to maintain and partially rebuild existing barays and canals, with the hydraulic system still meeting the capital's agricultural and religious water needs.
4. c. 1350–1400Angkor plain · CambodiaThe eastward shift of the political center, warfare, and climate change combined to interrupt maintenance of the large-scale hydraulic works; the reservoirs silted up, and the population and agricultural carrying capacity of the Angkor region declined markedly.