Colo. Rev. Stat. § 37-21-102
The board of directors shall hold a regular meeting in the office of the drainage district on the first Tuesday in January, April, July, and October and such special meetings as may be required for the proper transaction of business. Special meetings shall be called by the president of the board or any director. All special meetings of the board shall be held at locations which are within the boundaries of the district or which are within the boundaries of any county in which the district is located, in whole or in part, or in any county so long as the meeting location does not exceed twenty miles from the district boundaries. The provisions of this section governing the location of meetings may be waived only if the proposed change of location of a meeting of the board appears on the agenda of a regular or special meeting of the board and if a resolution is adopted by the board stating the reason for which a meeting of the board is to be held in a location other than under the provisions of this section and further stating the date, time, and place of such meeting.
C.R.S. § 37-21-102