Neb. Rev. Stat. § 2-32,102

The State of Nebraska may enter into agreements for the purpose of providing interstate cooperation and coordination in matters relating to natural resources with two or more of the following states: South Dakota, North Dakota, Montana, Wyoming, and Colorado. These states have cultural, economic, social, agricultural, and natural resources similarities as evidenced by such states' (1) past affiliations in interstate organizations such as the Old West Regional Commission and the Missouri River Basin Commission and (2) identity as reclamation states in the Upper and Lower Regions of the United States Bureau of Reclamation.