The construction of viaducts included the northern and southern sections of the Red Line and a section of the Green Line. 

Work on Doha Metro's viaducts first started in August 2015. Since then a total of 8.7km of viaducts has been completed, made up of 2,293 segments erected by five launching gantries. These generally span around 80m in length and have a total weight of approximately 381t; they are used so that viaduct erection can continue with minimum disruption to traffic.

Qatar Rail managing director and chairman of the executive committee, Abdulla Abdulaziz Al Subaie said, "I am delighted to be present to witness this significant milestone as the final segment was lifted in to place, completing all viaducts across the Doha Metro Project. Completion of the elevated viaduct sections is yet another important accomplishment following the tunnelling completion of the Doha Metro project. The viaduct completion is key, as its lines connect to significant landmarks such as Al Rayyan Stadium, Lusail Stadium, and Al Wakra City, as well as Qatar University and Lusail City in the west. In addition, it provides what will be important links between Doha, The Mall of Qatar, and Al-Riffa area. Overall completion of Doha Metro now currently stands at 51%." 

The first phase of the Doha Metro is expected to be complete in 2020, when the project's 37 metro stations are expected to be in operation, with an average journey time of two minutes between adjacent stations.