Kai Qu
Digging waterways and ditches.
Kai Qu refers to digging waterways and ditches, with the purpose of directing water flow for irrigation, drainage, or transportation. Water conservancy projects are vital to agricultural societies, and the smoothness of ditches directly affects the harvest of fields. Because it involves digging earth and altering water flow, traditional date selection pays special attention to it, choosing days that are suitable for earth-moving and favorable for water-related activities. Modern equivalents include engineering projects such as digging irrigation canals, drainage ditches, or water diversion channels.