When Rivers Became Drainage. Sanitation, Drainage, and the Creation of the Modern City

Every year, during the rainy season, floods return to Mexico City as if water insisted on running through its old courses. Despite having rivers piped and building roads over them, water accumulates in tunnels, under bridges, and in lower areas, such as the Río de la Piedad Viaduct. These scenes recall the city’s lacustrine past, and the direction taken by the combined drainage system, designed at the end of the 19^th century to clean and drain the Mexican capital, mixing rainwater and wastewater in a single network. Over time, this system became radicalized: rivers, canals and ditches became drains, turning water into a waste vehicle to be expelled out of the basin. This decision marked the way in which the city today experiences its floods and droughts, its subsidence, and its supply problems. This article explains that transition and shows how the modern city was built on that idea.

A TERRITORY AMONG CANALS AND DITCHES
There was a time when the Mexican capital was a patchwork of small settlements, agricultural areas, and water systems. Rivers, canals, and ditches ran through the plateau like liquid paths that articulated towns and neighborhoods; daily life was organized around water. Villages depended on water currents to farm, transport, and other household chores. A canoe on the shore, a spring next to the house, a well that supplied several families: the relationship with the environment was direct and visible.

La Viga Canal, Mexico City, 1902.
 Joseph Wharton

However, for 19^th century engineers, doctors, and officials, the city was “saturated with water” and literally “resting in a swamp.” It was rather composed of “interior ditches, infected wells, perpetually flooded squares, large pipes uncovered and flooded, which were a deposit of all kinds of filth and waste,” so they considered that the subsoil was “infested by decomposing organic matter” (“Las enfermedades de la estación,” 1903). Water bodies, considered swamps of rotten water, sources of disease, dirt and disorder, had to be disciplined by engineering to ensure a healthy environment.

In this context, Roberto Gayol, an engineer of the city at the end of the 19th century, came to the conclusion that the system that best suited the Mexican capital was one combined to simultaneously solve two of the most important concerns of the time: sanitation and drainage, which included expelling stagnant water and waste from the city. Sanitation was to eliminate the unhealthy conditions derived from wastewater, and draining implied channeling excess water out of the basin. Rainwater was thought of as a vehicle to expel excreta and even to clean the conduits, while contributing to the gradual drying up of the lakes, rivers, and canals of the Mexico Basin.

The adoption of this system, however, found intense controversy that went beyond the technical realm to become a political and moral debate about the kind of city that was sought to be built and about the relationship it should maintain with its water. In the Association of Engineers and Architects of Mexico (AIAM) and in the press, there was discussion about what type of sanitation system should be implemented from various techniques available: interception or dry route, pneumatic, and water transport systems in divided and combined modes.

Two imaginaries clashed. The first model, promoted by Gayol, was based on the miasmatic theory that associated unhealthiness with contact with the putrefaction of stagnant filth; a dry city was a civilized city. The second model was defended by agricultural engineer Andrés Basurto, a member of the AIAM attentive to microbial science. He proposed to separate wastewater from rainwater by means of closed pipes, considering that mixing the flows favored the spread of diseases and that sewage water should not be used in agriculture without first destroying germs through heat.

Tools for the manual cleaning of sewers and drains, Mexico City, 1904.
Mobile cart with winch and steel cable to operate the tow “rake” that was inserted into the manholes; the crew would tighten the cable and drag the bundle along the conduit to remove grease and organic matter. This operation complemented the daily hydraulic flushing.
 Museo Archivo de la fotografía

The combined drainage system began operation, however, in 1903 with an underground network of 122 kilometers, covering about 30 square kilometers: the part affected by the floods. The innovation that Gayol was most proud of was its system of washing tanks that in five hours “discharged up to 120 liters per second to carry sediments and keep the drains expeditious throughout the year,” with an approximate use of 18 million liters of water per day, equivalent to more than seven Olympic swimming pools. In addition to rinsing with water, “brushes and heavy mops were used to release grease and debris adhering to the walls.” In total, the cost of this operation was estimated at “82 dollars per mile.”

The collectors of the combined system flowed into the Gran Canal del Desagüe (Great Draining Canal), near San Lázaro. At this point, known as kilometer zero, Gayol installed four pumps and a set of floodgates to regulate the flow and direct it to the initial 47.5-kilometer stretch of the open canal, followed by a dam and a tunnel that took the current towards the rivers that carried the flow to the Gulf of Mexico. This work, built during Porfirio Díaz’s dictatorship and inaugurated in 1900, set a long-term trajectory.

After the Revolution, this infrastructure was incorporated into the State reconstruction project. In 1928, with the creation of the Department of the Federal District (DDF), the works related to combined drainage were resumed and began to be presented as a public service that had to be provided to an expanding population.

During the 1930s, the Planning Law and its Regulations contributed to the idea that traditional rivers and canals—agricultural and navigable—were seen as obstacles to urban development. The aversion was directed at water and at the whole set of identifications of the rural with the precarious, the unproductive, the residual. In this framework, the city grew over old riverbeds, covered them with asphalt and integrated them into the combined system. The original financing came from a loan of 25 million pesos contracted in 1933, with which the drainage networks were expanded and streets were paved.

Beginning of the Grand Drainage Canal in San Lázaro and connecting works with the internal drainage collectors. Mexico City, 1898.
The first photograph records the start of the open-air canal; the following ones show the foundation, the piles, and the gates installed to connect the combined system with the Grand Canal.
 Museo Archivo de la Fotografía

THE EXPANSION OF THE COMBINED SYSTEM MADE THE DIFFERENCES BETWEEN RIVERS, NAVIGABLE CANALS, AND DRAINAGE CHANNELS DISAPPEAR, BY MIXING RAINWATER AND WASTEWATER IN THE SAME INFRASTRUCTURE. THIS INTEGRATION MODIFIED THE FUNCTIONS AND MEANINGS OF WATER BODIES TAKING WATER OUT OF THE CITY REPLACED THE IDEA OF LIVING WITH IT

Large collector installed on Calzada de Los Misterios, Mexico City, 1928 The photographs document the expansion of the combined drainage system undertaken with the creation of the Department of the Federal District.
 Museo Archivo de la Fotografía

The expansion of the combined system made the differences between rivers, navigable canals, and drainage channels disappear, by mixing rainwater and wastewater in the same infrastructure. This integration modified the functions and meanings of water bodies. As the streams were jointed together, they also began to be named interchangeably: rivers and canals were perceived as bodies of dirty water that had to be covered and hidden. Thus, taking water out of the city replaced the idea of living with it.

The path taken explains the current difficulty in introducing separate networks or modifying the organization of flows, since the inherited technical structure persists as the dominant framework in urban water management [see in this issue the review of The Submerged City by Manuel Perló, pp. 330].

PIPES
The canalization works began at the end of the 1930s and were carried out in sections during the following decades. The systematic piping of the rivers that crossed the urban area began. As for the canals, some dried up and others, like the rivers, were incorporated into the network to function as means of capturing and transporting rainwater and wastewater. But starting in the 1960s, these water bodies were channeled to integrate them into the deep drainage system. Only a few canals linked to chinampa agriculture remained in Xochimilco and Tláhuac, which over time have been reduced and are today at permanent risk.

One of the first courses to be piped was the Churubusco river, central axis of the drainage, to which numerous streams from the southwest of the basin tributed, including the Eslava and Magdalena rivers up to the Mixcoac. Later, work was carried out on the La Piedad river, which collected the water of the Becerra and Tacubaya rivers. It was thought that it was a “vital public service” aimed at “turning the bed of the old and cumbersome river into a magnificent boulevard, giving outlet to the sewage through a network of pipes connected to the collectors that rid the capital of the antigenic flow.”

In the 1950s, the piping of the Consulado river was undertaken with the aim of “disappearing one of the antigenic city areas” and giving way to “the creation of a new and beautiful boulevard.” Once piped, “with its paving, profuse lighting, and drainage,” it was believed that the inhabitants would enjoy a climate of hygiene and cleanliness (“Moderna y bella avenida en el Río del Consulado,” 1957).

River piping work on the La Piedad River near Colonia del Valle, Mexico City.
 Museo Archivo de la Fotografía

The paving came to seal riverbeds, to level the land, to cover the bodies of water, and to support new roads. At that time, cement was reputed to be “the greatest civilizer… ready to assume the shape and color that they want to give me and then cut me into a rock of formidable nobility.” This “imperishable artificial stone” became the material of the urban transformations of the 20th century (Monroe, 1925). Cement was a technology of order: its incorporation made it possible to develop a robust road infrastructure that contributed directly to the project of drying out and solidifying the city.

CEMENT WAS A TECHNOLOGY OF ORDER: ITS INCORPORATION MADE IT POSSIBLE TO DEVELOP A ROBUST ROAD INFRASTRUCTURE THAT CONTRIBUTED DIRECTLY TO THE PRO JECT OF DRYING OUT AND SOLIDIFYING THE CITY

Paving work for the completion of the Miguel Alemán Viaduct over the La Piedad River, Mexico City, December 22, 1955
 Museo Archivo de la Fotografía

SHOULD WE UN-PIPE?
Although the names of rivers and canals remain today on those of streets and Metro and Metrobús stations, the city lost with them elements that previously constituted identity, and historical and relational references for its inhabitants. A way of inhabiting detached from water-related practices, disconnected from lake ecosystems, was imposed, generating what Marc Augé has called “non-places” of modernity: functional and anonymous scenarios designed for transit rather than for encounter.

However, the renewed interest in rivers and water restoration policies shows that this past remains open. Analyzing the pipeline as a history of political decisions allows us to recognize that the channels were scenarios where urban priorities, territorial disputes, and specific ways of ordering collective life were settled. Reviewing this process in the light of the present opens the possibility of rethinking the relationship between water, territory, and urban life as a necessary condition for imagining other forms of city and coexistence with water.

Map of rivers and works in the Valle of Mexico, end of the 1940s.
 Archivo del agua

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