Regarding water, Mexico City is struggling with a paradoxical situation: On one hand, there is a shortage of drinking water – and on the other, torrential downpours flood the streets every year. Parque Hídrico Quebradora is designed to usher in a new era of water management.
Mexico City is located in the Valley of Mexico, a high-altitude plateau at over 2,000 meters above sea level. It is surrounded on three sides by mountains, including the two volcanoes Popocatépetl and Iztaccíhuatl. In the middle of the plateau was once Lake Texcoco. On a small island in that lake, the Aztecs founded the city of Tenochtitlan in the early 14th century. The city was destroyed in the siege by Spanish conquistadors, and on its ruins the Spaniards built Mexico City. Today, the metropolis with around 20 million inhabitants is one of the largest in the world. Lake Texcoco was gradually drained as the population grew and it’s now completely dry – with grave consequences. Desert has taken hold, and endemic animal and plant species have died out. Groundwater has been continuously pumped for drinking water, which has caused the water table to drop significantly. Against this background, it seems almost bizarre that the city also has to cope with heavy rains that cause flash flooding of entire neighborhoods every year.
Manuel Perló Cohen (left) is an internationally renowned full-time researcher at the Instituto de Investigaciones Sociales of the Universidad Nacional Autónoma de México (UNAM) in Mexico City. He holds a doctorate from the University of California (UC) in Berkeley. Perló Cohen has investigated the subject of water in several publications, including the question of whether water could one day become the cause of serious conflict in the Valley of Mexico.
Loreta Castro Reguera (below, left) studied architecture and urban design at UNAM, at the Accademia di architettura di Mendrisio (AAM) in Switzerland, and at the Harvard University Graduate School of Design in the USA. For several years she has been dividing her time between a professorship at the School of Architecture at UNAM and her position as design director at the architectural office Taller Capital. She too has dealt with issues of sustainable water management many times.
With approximately two million residents, Iztapalapa is the most populous of Mexico City’s 16 boroughs. The name means “slates over waters”, an allusion to the location on the former south bank of Lake Texcoco. Although the lake is gone, water remains a defining theme for Iztapalapa. Water supply in the borough is deficient. Tap water is not always available and the quality is poor.
The aquifer that used to be the main source of water for the Mexican capital has been pumped nearly dry. Water from other basins is being channeled through the Cutzamala system at great expense, but the supply is enough for only one third of the population of the capital city. Making matters worse, the pipeline system is dilapidated, and around 40 percent of the water is lost. Tank trucks are being used in stop-gap efforts, but the water they deliver is also of poor quality. Bottled drinking water has therefore become part of everyday life in the city. Some families use up to 20 per cent of their income just to buy water.
Paradoxically, Mexico City and Iztapalapa are also struggling with too much water – in the form of heavy downpours. The city is located in the Basin of Mexico, one of the few closed or endhorreic basins in the world. This means that all the rain that falls in the area has no natural exit. This problem is exacerbated by the fact that the basin soil is saturated and the sewer system is clogged with garbage in many places. Adding to the woes, Mexico City is subsiding, which causes damage to the sewer system, as do the earthquakes that repeatedly shake the city. The whole situation is particularly acute in Iztapalapa because the borough is located at the lowest point of the basin and storm water from the higher elevations naturally flows there.
Read the full article: “The shaping of water” in Fifth LafargeHolcim Awards – Sustainable Construction 2017/2018