Angkor Khmer Hydraulic Irrigation System

Timeline

1. c. 900–1050Angkor region · CambodiaSuccessive monarchs built reservoirs and diversion channels around Angkor, using monsoon rainfall and the seasonal rise and fall of the Tonlé Sap to regulate water supply and expand irrigable rice fields.
2. 1161–1170East Baray and the area around Angkor Thom · AngkorIn the 1160s large barays such as the East and West Barays and the canal network operated in full, supplying irrigation water to hundreds of thousands of residents, monks, and artisans in the Angkor metropolitan area and supporting dense temple construction and urbanization.
3. c. 1181–1220Angkor metropolitan area · CambodiaDuring Jayavarman VII's reign hydraulic facilities were further maintained and expanded; newly built public buildings such as hospitals and postal relay stations also depended on a stable water supply, and the system reached its peak scale.