Missions of the Irrigation Association are stipulated in the following:
1.The initiation, improvement, maintenance, and management of farmland irrigation operations;
2.Precautionary and rescue measures in the event of disasters and threats on farmland irrigation operations;
3.The raising of expenditure and institution of funds for farmland irrigation operations;
4.Research and development projects for the interests of farmland irrigation operations;
5.The collaboration with government over land, agricultural, and industrial policies, and rural village development programs;
6.Affairs and projects consigned by supervising authorities.

In regard to construction lots necessary for the establishment or improvement of irrigation facilities, the Irrigation Association shall lease, or buy, from land owner or other encumbrancers; if both parties fail to reach an agreement, the Irrigation Association shall ask supervising authorities to collect the lots in conformity with the law.　If the lots are publicly owned, the Irrigation Association shall apply for a lease or purchase plan.
For lots originally used for irrigation projects, they shall be put to use as of old.　During such periods, land taxes on the lots shall be exempted.

The Irrigation Association shall proceed with any measurement and investigation project for the purpose of establishing irrigation facilities.　If, during such, measurement and investigation projects require the removal of any obstacles, the Irrigation Association shall notify local county (or municipal) administrations, informing land owners or occupants for removal of the obstacles.
Should accidents result from the aforementioned obstacle removal, land owners or occupants shall ask for indemnity.　Supervising authorities shall mediate disagreements should there be any controversies.

The Irrigation Association shall report to supervising irrigation authorities to handle any mishaps in accordance with Water Act, Article 76, and detailed prescriptions in the event of floods, draughts, or natural disasters.