Colo. Rev. Stat. § 37-4-115
In case any property within or without any district is benefited, which for any reason was not appraised in the original proceedings, or was not appraised to the extent of benefits received, or in case any person or public corporation makes use of or profits by the works of any district organized under articles 1 to 8 of this title to a degree not compensated for in the original appraisal, or in case the directors of the district find it necessary subsequent to the time when the first appraisals are made to take or damage any additional property, the directors of said district, at any time such condition becomes evident, shall direct the board of appraisers to appraise the benefits or the enhanced benefits received by such property, or such damages or value of property taken, and the proceedings in articles 1 to 8 of this title for appraising lands not at first included within the boundaries of the district shall in all matters be conformed to, including notice to the parties; or the board may, at its discretion, make settlement with such person or public corporation for such use, benefit, damage, or property taken.
C.R.S. § 37-4-115