Colombia dual carriageway concession awarded A key Colombian dual carriageway concession has been awarded. Road Structures / January 29, 2021 1 minute 10 seconds Read SHARE A key Colombian highway concession package has been awarded – image courtesy of © Indos82, Dreamstime.com The contract for the construction, operation and maintenance of Colombia’s Doble Calzada Oriente (DCO) dual carriageway has now been awarded. The concession package will be handled jointly by three firms, Conconcreto, Castro Tcherassi and Procopal. The companies have stakes of 60%, 30% and 10% ...