- Launched during the Department's Diamond Jubilee Celebration (60th anniversary) on January 1, 1992.
- The wave represents the five main functions of the Department of Irrigation and Drainage, namely irrigation, drainage, river engineering, coastal engineering and hydrology.
- The wave shape represents a dynamic Department, committed to progress unimpeded by obstacles in providing comprehensive services.
- The wave changing from blue to green signifies agricultural progress amidst the beauty of Nature, the result of harmonious integration between engineering work and the environment in line with the motto:
"Water and Its Environment, Our Heritage."
