The main business of this Office is to take the order of Water Resources Agency, Ministry of Economic Affairs, in charge of conducting the planning, design, new construction and maintenance of water conservancy in Yilan county with detailed as follows:
1.Planning：
The planning works contain hydrology data surveying, investigation, testing, analysis and planning of river drainage and jetty administration projects. There are 12 rainfall gauge stations and 8 water level-discharge stations and 45 groundwater observation wells in this region.
2.Flood Control：
This Office is in charge of the administration works and examination, maintenance and management of structural things for river conservancy of the river under the control of central government; as for the administration works and examination, maintenance and management of structural things for river conservancy of the river under the control of local government will be conducted by local government, and assisted by this Office in technology.
3.Irrigation & Drainage：
The irrigation and drainage works inside of Yilan county is conducted by Yilan irrigation Association, as for the area drainage works is managed and maintained by local government; however, this Office will be in charge of planning, design, construction of large work, and after completion, which will be managed by Yilan Irrigation Association or local government.
4.Jetty Construction：
This Office is in charge of planning, design, construction, reinforcement, and management.
5.River Management：
Survey and delimit the areas for management. Delegation of planting sand mining, in charge of water gate, patrol the river area, punishment of illegalities, etc.
6.Flood Prevention & Control：
If there is accident emergency happened in the flood season, the flood evacuation and rescue works should be conducted by the local government. We will offer the technology and equipment assistances. By the way, we implement relevant training and education programs.
7.Propaganda Works：
Create a water culture that both blends well with local heritage and features, and encourage community participation to achieve the ultimate goal of water sustainability.