Colo. Rev. Stat. § 31-12-406
The governing body of the consolidated city or town may pass, at the first meeting or as soon thereafter as possible, a resolution adopting in a body the ordinances of some one of the cities or towns forming the consolidated town or city as such ordinances existed at the date of consolidation. Upon the passage of the resolution, the whole of the ordinances of the city or town so designated as they existed at the date of consolidation shall become the ordinances of the consolidated city or town in the same manner as if they had been regularly passed and published by the governing body of the consolidated city or town and shall so remain until amended or repealed. They shall also make appropriation, by ordinance, for the expense of the then unexpired portion of the current fiscal or municipal year.
C.R.S. § 31-12-406
This section is similar to former § 31-8-307 as it existed prior to 1975.