Idaho Code § 42-3506
There shall be three (3) members of the Columbia Compact Commission from the state of Idaho. They shall be appointed by the governor with the consent of the senate and shall hold office at the pleasure of the governor. The terms of each of the initial three (3) members shall begin at the time of appointment, provided said compact shall then have gone into effect; otherwise, shall begin upon the date which said compact shall become effective. The term of one (1) of said three (3) commissioners first appointed shall be two (2) years, one (1) shall be four (4) years, and one (1) shall be six (6) years; and their successors shall be appointed by the governor with the consent of the senate for terms of six (6) years each. Each commissioner shall hold office until his successor shall be appointed or qualified. Vacancies occurring in the office of any such commissioner for any reason or cause shall be filled by appointment by the governor with the consent of the senate for the unexpired term. Any appointment made by the governor while the senate is not in session shall be effective as a temporary appointment until the next meeting of the senate when the governor shall present to that body his nomination for the office.
Idaho Code § 42-3506