Drainage through the time in Mexico City.

Since the Mexicas arrived in Tenochtitlan (nowadays Mexico City) in 1325 and settled, they developed impressive and innovative engineering works to avoid the floods that affected the inhabitants due to the geographical location of the place and due to the lakes that Formed the area; This hydraulic system distributed: rainwater, water for human consumption and sewage. This system allowed that in times of rains it would be avoided floods, as well as to have some cleaning in the city since the pre-Hispanic inhabitants were extremely clean. On the arrival of the Spaniards to Tenochtitlan, they were surprised to see the hydraulic systems, dykes and a distribution system of hot and cold water that existed in that time, as well as drainage that was said to have the palace of Netzahualcóyotl.

It is important to consider that in Europe between 1300 and 1492 there was no drainage system and the habitants of that time had very unhygienic customs: houses were suffocating and lacking ventilation, the smell of rotting of the graves where the excrement with urine and vinegar was extremely strong and mixed with the stench of urine that was thrown from the windows, not sprinkled with sand. These practices subsequently led to major pandemics in Europe, which killed thousands and destroyed one-third of the population.

During and after the colony between 1555 and 1604, the water level was exceeded and several floods arose which caused the construction of dikes, causeways and several projects that allowed to drain the Valley of Mexico. In 1607 a hydraulic work was approved to dry the lake, which ended eleven months later with the help of thousands of natives who worked hard to dry, which caught the attention of the Spaniards.

New drainage projects were carried out over the years as drainage channels to avoid the problems caused by floods and chaos in the transportation of different kinds of water.

Currently, more than 8 million of people have designed different drainage systems and wastewater treatment plants, which allow the evacuation and control of water levels to avoid flooding which can have serious consequences for the habitants.

Due to the great growth of Mexico City and to avoid the collapse of the drainage, mega hydraulic works are being carried out, such as the Emisor Oriente Tunnel, which aims to solve the problem of subsidence due to the excessive pumping of groundwater and the intense rains that cause drainage to be insufficient. The tunnel will have a distance of 62 kilometers, 7 meters in diameter and an evacuation capacity of 150 cubic meters per second, which will be inaugurated in 2018. This tunnel will dislodge wastewater and rainwater from Mexico City.