C.R.S. § 37-84-106
37-84-106. Bridges over ditch - maintenance
37-84-106. Bridges over ditch - maintenance. All bridges constructed over any ditch, race, drain, or flume crossing any public highway, street, or alley, after construction, shall be maintained by and at the expense of the county or municipality in which such ditch, race, drain, or flume may be situated.