Valle de Chalco, officially named Valle de Chalco Solidaridad, is a municipality located in Mexico State, Mexico, on the eastern outskirts of the metropolitan area of Mexico City. Formerly part of the municipality of Chalco, it was split off as a separate entity in 1994, during the presidency of Salinas de Gortari, under his Programa Nacional de Solidaridad (National Solidarity Program). The municipality lies on the old bed of Lake Chalco, which was substantially drained in the nineteenth century. Technically, the municipal seat is Xico, after a high point of land that once formed an island, and now remains as a small hill within an otherwise monotonous, urban expanse. "Chalco" refers to the Chalca tribe, whose territory covered the area around the lake, prior to the Spanish Conquest of Mexico.
As of 2006, Chalco was part of the world's largest mega-slum, along with Neza and Izta.[1]
Pre-Columbian history
Archeologists date human settlement around Lake Chalco from about 2400 B.C, but major settlement occurred at approximately 1240 B.C., when the first tribe to call itself Chalca migrated to the region. This tribe was followed by others, ethnically and linguistically diverse, who added the name Chalca to their own. By 1410 the Chalca territory had developed into a loose confederation, divided into four, semi-sovereign domains. In the early 14th century the Mexica tribe of the Aztecs settled in nearby territory and began to build their city of Tenochitlan, now Mexico City. Over time, the Chalcas and Mexicas engaged in a number of ritual wars, known as Xōchiyaoyōtl or Flower Wars. During the Spanish Conquest of the Aztecs, the Chalca allied themselves with Hernán Cortes and his troops.[2]
Modern history
Only half a percent of the Earth's water is suitable for human consumption. The other 99.5 percent is saltwater or locked up in glaciers and icecaps. With the world’s population ever-growing, and moving to already water-challenged areas, if there were a way to make some of that 99.5 percent potable, we’d slake a lot of thirst. There is a way, of course. The U.S., and many other countries, have desalination plants that annually produce billions of gallons of water. The processes for doings so, however, are currently too costly to be considered as solutions for places that need, and will need, water most. Better Desalination Solving the tough issues of desalination may require innovations that grow from mixing different disciplines. That's where Sandia National Laboratories’ researcher Tom Mayer comes in. He has the job of identifying researchers with knowledge in different fields and matching them up with new types of research that may lead to better desalination methods. Most people doing research on projects in his long-range R&D program have never before worked in water treatment. " Some of the research may provide just the answers we are looking for," he said. "But we may not see the results for five or ten years." In one instance, Mayer tapped Chris Cornelius, who has been developing membranes for hydrogen fuel cells, to build a better electrodialysis membrane. Electrodialysis removes salts or ions from water with an electric field and special ion-exchange membranes. "Electrodialysis is well-known, but not popular in the U.S.,” Mayer said. “But there are real possibilities for its use. If we develop a better membrane, it may make the technology more attractive." Part of the high cost of turning salt water to fresh is the cost of cleanup. On the coasts, the solution is simple—return the salt and minerals to the ocean. But inland, getting rid of the residual becomes problematic. Richard Kottenstette, who heads the Jumpstart R&D portion of Sandia's Advanced Concepts Desalination program identifies and pursues technologies that are nearly ready for commercialization and that can tackle this problem. Kottenstette is working with the University of South Carolina to investigate better mineral recovery. Cleanly harvested minerals can be sold. Another method reuses water that comes from sewage at the Rio Rancho wastewater treatment plant. "If you use it twice, you double its value," Kottenstette said. Treated wastewater is typically used to water parks and golf courses, but there is a possibility it could be made as fresh as if it came out of an aquifer. The phosphorous from the waste could be turned into fertilizer. Kottenstette also worked with a New Mexico State University graduate student, as well as with the Texas Bureau of Economic Geology, to put Mineral waste from reverse osmosis into a landfill, over a liner that could self-heal if it were breached. What’s Next? The next step after developing a better desalination method is commercialization. That task falls to Sue Collins, who works with Sandia's licensing department. "End-user interest is growing steadily and that is important to our work with the manufacturing community," Collins said. "Our customers and advocates have said repeatedly that the success of commercialization efforts will be measured in gallons of new water produced."
Under the presidency of Porfirio Díaz, much of the drained lake bed formed part of a latifundia, the Hacienda de Xico. Following the Mexican Revolution, land ownership was reformed into the ejido system of communal ownership, and was utilized primarily for dairy farming by the communal owners, or ejidatarios. This began to change near the end of the 1970s, as hundreds of homesteaders, generally from Mexico City and adjacent urbanized areas, descended upon the region. Most purchased their homestead plots illegally from ejidatarios. The new settlement grew despite the lack of basic infrastructure, such as potable water, sewers, electricity, public transport, medical services and schools. It was only with the initiation of the Programa Nacional de Solidaridad, in 1988, that the federal government began to install basic services and, ultimately, regularize the tenancy of 77,000 homesteads.[3]
During the decades of the 1980s and 1990s, Valle de Chalco expanded dramatically in population; by 1995 the city had 287,073 residents. Growth has since slowed, as undeveloped land becomes less available; in 2005, there were 332,279 residents.[4] By the 2010 census it had grown to 357,645.
Towns and villages
Localities (cities, towns, and villages) are:[5]
| Name | 2010 Census Population |
|---|---|
| Xico | 356,352 |
| Colonia Ampliación (San Miguel Tláhuac) | 742 |
| Santa Cruz | 228 |
| El Triángulo | 203 |
| Comalchica | 109 |
| Ejido Tulyehualco (Tabla Número Nueve) | 8 |
| El Invernadero | 3 |
| Las Bombas | 0 |
| Total Municipality | 357,645 |
References
- ^ Mike Davis, Planet of Slums, La Découverte, Paris, 2006 (ISBN 978-2-7071-4915-2), p. 31.
- ^ "History of Chalco". Website of the Municipality of Chalco (in Spanish). Retrieved May 26, 2009. [dead link]
- ^ "Valle de Chalco Solidaridad". Enciclopedia of the Municipalities de Mexico(in Spanish). Retrieved May 25, 2009. [dead link]
- ^ "2005 Mexican Housing and Population Count". Instituto Nacional de Estadistica y Geografica (in Spanish). Retrieved May 26, 2009.
- ^ 2010 census tables: INEGI