Colo. Rev. Stat. § 31-21-303
Nothing in this part 3 shall release or discharge any special assessment which is a lien on or against any property. Any municipality issuing bonds under this part 3 shall be subrogated to the rights of the holders or owners of the outstanding special assessment bonds or obligations paid. If, after the issuance of bonds authorized by this part 3, the delinquent or defaulted special assessments, or any part thereof, are collected and the special assessment bonds or obligations payable out of the particular special assessment fund have been redeemed by means of bonds issued under this part 3, the amounts so collected shall be used to pay the principal of and the interest on the bonds authorized and the tax levies therefor shall be reduced in a like manner.
C.R.S. § 31-21-303
This section is similar to former § 31-21-304 as it existed prior to 1975.