The Emisor Oriente Tunnel (TEO) is one of the largest deep drainage systems in the world with 62 km length and a 7 m diameter tunnel. Prefabricated reinforced concrete voussoirs were built (more than 22,000 rings) among two precast plants and the definitive lining used reinforced concrete placed on site. The first shields were designed and built in Mexico for the drilling and construction of tunnels using a 3 m diameter Caldwell shield with a sloping starting edge and two oscillating cutter systems with three arms each, which allowed the manual placement of temporary support metal rings. Considering the clayey soil conditions of Mexico City’s Valley, Earth Pressure Balance (EPB) method was used (Herrenknecht and Robbins tunneling machines) to maintain the frontal pressurization and stabilize the terrain combining the tunneling process with the controlled extraction of the excavated material. The project benefits more than 20 million inhabitants of the capital, mitigates the risk of flooding and increases the capacity of lead and convey sewage up to 150,000 l/s. For the construction were built 25 access wells (25-145 m depth), were used 142 thousand tons of steel, 1,300,000 m3 of concrete, 4,700,000 m3 of materials were excavated and more than 4,000 people worked 24 h. TEO is not only an example of a tremendous infrastructure work, but also a successful long-term project with wide inter-institutional cooperation and a great social impact that fostered local employability, learning capabilities for precast, water awareness and environmental mitigation measures.