Reviews of urban linear drains
Introduction
Line 3 of the Mexico City Metro is one of the twelve Metro lines in the capital of Mexico. It was inaugurated on November 20, 1970 and is the third line to join the system. It is made up of 21 stations and 23.6 kilometers of tracks. It covers the mayorships Gustavo A. Madero "Gustavo A. Madero (Mexico City)"), Cuauhtémoc "Cuauhtémoc (Mexico City)"), Benito Juárez "Benito Juárez (Mexico City)"), Álvaro Obregón "Álvaro Obregón (Mexico City)") and Coyoacán. It corresponds to seven Metro lines and its distinctive color is olive green.[2] In 2022 it was the second busiest line on the network, with more than 164 million passengers.[3].
History
Construction
The construction of line 3 of the Mexico City Metro was contemplated in the initial project of the network, along with lines 1 and 2.[4] It was planned by engineer Bernardo Quintana Arrioja, founder of Empresas ICA; financed by the Department of the Federal District through a loan granted by the French government; and it was entrusted to the Collective Transportation System, a public body created to manage the metro.[5][6].
The original project for line 3 contemplated connecting the Basilica of Guadalupe, in the north of the city, with the Churubusco area to the south. However, the northern layout of the route was discarded because it would interfere with the operation of the feeder drains of the Gran Canal del Desagüe "Gran Canal del Desagüe (Mexico City)"), one of the main engineering works that prevents the flooding of Mexico City. The connection with the Basilica of Gudalupe was replaced by a route to the Tlatelolco area. Several of the initially planned stations changed names when the project was implemented. The "Martínez de la Torre" station was renamed Guerrero "Guerrero (station)") and the "Morelos" station was renamed Juárez "Juárez (station)").[7].
The construction was done through open-air excavations. Due to the nature of the soil, abundant in water tables as it was the bed of the ancient Lake of Texcoco, it was necessary to isolate the water from the work area by electrosmotic pumping of liquids and the construction of walls parallel to the construction area before starting the excavation work. The weight of the finished structure had to be equivalent to the weight of the earth removed in the excavation to prevent the tunnels and stations from sinking into the soft ground below.[8].