Utah Code § 73-6-1

For the purpose of preserving the surplus and unappropriated waters of any stream or other source of water supply for use by irrigation districts and organized agricultural water users, or for any use whatsoever, when in the judgment of the governor and the state engineer the welfare of the state demands it, the governor by proclamation may, upon the recommendation of the state engineer, suspend the right of the public to appropriate such surplus or unappropriated waters.