In order to improve the environmental conditions for the more than seven million inhabitants of the Colombian capital, Bogotá, work is underway to prevent untreated water being fed into the Bogotá, Fucha and Tunjuelo rivers. Modern sewers are being constructed to collect the sewage and channel it to two treatment plants.
Six EPB Shields in total as well as one AVN600XC set to to work for several sections of the large-scale project between 2000 and 2012. Almost 40 kilometers of sewage tunnels were produced either by pipe jacking or with segmental lining. The constrction companies opted for moulds and segment handling equipment by the Herrenknecht subsidiary Formwork.
The front-runner is an EPB Shield (EPB3750AH, diameter: 4,520mm) that delivered 896 meters of tunnel within one months. After only 18 months, 9.5 kilometers of tunnel had been excavated - much earlier than expected despite challenging spatial curve drives.