Colo. Rev. Stat. § 37-20-110
When the prayer of the petition is that a drainage system be established without holding an election and it appears that a large portion of the land which will be benefited by the proposed drainage system is unoccupied land or so many of the owners of land to be benefited thereby are not residents upon the land that an election would be impracticable or would entail an undue expense, the board of county commissioners is authorized, at any regular or special session, to cause a system of drainage to be constructed and to exercise all the powers conferred upon boards of directors of drainage districts, and to continue to exercise the powers and perform the duties of boards of directors until a petition is presented signed by the owners of the larger portion of the lands, or their duly authorized agents, praying that an election may be called to elect directors for the district. Then the board of county commissioners shall call an election for that purpose and as soon as the result of said election is determined, the board of county commissioners shall cease to have or exercise the duties of directors of a drainage district.
C.R.S. § 37-20-110