Neb. Rev. Stat. § 70-620.01

In districts receiving annual gross revenue of less than forty million dollars, a general manager may be employed on such terms as the board deems advisable. He or she shall be chief executive officer of the district and, subject to the control of the board of directors, shall manage, conduct, and administer the affairs of the district in an efficient and economical manner. In those districts receiving annual gross revenue of forty million dollars or more, a chief executive officer, who shall be designated as general manager if the board appoints a president of the board or as president if the board appoints a chairperson of the board, may be employed on such terms as the board deems advisable and, subject to the control of the board of directors, shall manage, conduct, and administer the affairs of the district in an efficient and economical manner.