Colo. Rev. Stat. § 37-90-132
The board of directors may levy and collect annually taxes necessary to finance the activities of such district to the amount of not more than two mills on the dollar of the valuation for assessment of all taxable property within the district. It shall, in accordance with the schedule prescribed by section 39-5-128, C.R.S., certify its mill levy to the board of county commissioners of the counties wholly or partially within the district, who shall extend the same on the county tax list, and the same shall be collected by the county treasurer in the same manner as state and county taxes are collected. In addition, annually the board of directors of the district may assess and certify a special assessment on all water wells, except those wells described in section 37-90-105, in the district not to exceed fifteen cents per acre-foot of the maximum annual volume of the appropriation of each such well. Said assessment shall be collected by the county treasurer in the same manner as other special assessments. It is the duty of the board to apply for and to receive from the county treasurers all money to the credit of the district.
C.R.S. § 37-90-132