The Autonomous City of Buenos Aires (CABA), Argentina, has a subsoil rich in streams, practically none of which can be seen visually today, except for a few meters from some of their mouths, in the Río de la Plata and the Riachuelo. Like many other cities in Latin America, Buenos Aires developed along the banks of various natural watercourses (streams, ravines, and small lagoons) and, for decades, it was possible to generate a coexistence between the natural features typical of the rainwater systems and the uses and customs of the population.
The former Federal Capital is crossed by the following streams: Medrano, Vega, White, Maldonado, Radio Antiguo-Ugarteche, Boca-Barracas, Ochoa, Elía, Erézcano, Cildáñez and Larrazabal-Escalada. Of these basins, three of the five most important also extend into the conurbano (the conglomerate of municipalities surrounding the city): the Cildáñez, the Maldonado and the Medrano, which have their headwaters in the Province of Buenos Aires. The vision of progress towards the end of the 19th century and the beginning of the 20th century imposed a rapid advance of the urbanizations on the watercourses, which had become inconvenient obstacles.
The priority was to hide them from the panorama, favoring the development of neighborhoods, infrastructure, and services. In this way, a line of action that sought to reduce the natural features of the terrain to their minimum expression continued. Although there was a time of transition, when Buenos Aires, as a concept of modern city, included in its urban fabric the idea of open-air canals, which served as a place for recreation, this was gradually abandoned. The natural drainage system, composed of the streams that crossed CABA in the open air, was almost completely replaced by a set of outfalls and secondary conduits buried and piped, through works carried out mainly between 1927 and 1954.For those who are not familiar with the technical jargon, a piping («culvert», in English; «canalisation souterraine», in French) is a conduit, usually of reinforced concrete and rectangular or circular section, through which a watercourse is artificially conducted.
I invite everyone to read Matias’ post with the topic of the day.