C.R.S. § 31-23-213

When a commission has adopted a major street plan for the territory within its subdivision control, or any part thereof, as provided in section 31-23-208 , and has filed a certified copy of such plan in the office of the county clerk and recorder of the county in which such territory or such part is located, no plat of a subdivision of land within such territory or such part shall be filed or recorded until it has been approved by such commission and such approval entered in writing on the plat by the chairman or secretary of the commission.