Test wells being drilled to assess Mexico City’s deep water aquifer

 Mexico's geography in the Press, Updates to Geo-Mexico  Comments Off on Test wells being drilled to assess Mexico City’s deep water aquifer
Sep 132014
 

Pemex, Mexico’s state-owned oil giant, will start drilling the first of two deep exploratory wells in Mexico City later this month to investigate an aquifer deep below the city that is believed to hold vast quantities of potable quality water. For further background, please see our previous post on this topic:

The test wells are part of a $30 million multi-agency study now underway that incorporates experts from the Water System of Mexico City (SACM), the National Water Commission (CONAGUA), the engineering and geology departments of the National Autonomous University of Mexico (UNAM), and Pemex, which is providing the technology to drill the wells.

Later this month, Pemex will start drilling the first 2000-meter-deep test well in the Magdalena Mixhuca Sports City area, in the eastern part of Mexico City. Each well will cost an estimated $7.6 million to complete.

Schematic stratigraphy of the southern portion of the Basin of Mexico.

Schematic stratigraphy of the southern portion of the Basin of Mexico.
Source: Adapted from Mooser, 1990.

Ramón Aguirre, the CEO of SACM, says that the two test wells will target two different zones, increasing the chances of demonstrating the value of the aquifer as a viable source of water for Mexico City. In particular, Aguirre expects the wells to help confirm that there is an impermeable cap of clay separating the deep aquifer from the principal aquifer in the area (from which water is already extracted). An impermeable layer would mean that water could be safely removed from the deep aquifer without leading to downward drainage of water from the aquifer above. It is expected to take about two years for the initial studies to be completed.

In its National Water Plan, CONAGUA has warned that population growth in the Valley of Mexico could result in serious water shortages by 2030, reducing annual availability from about 4,230 cubic meters/person to less than 1,000 cubic meters/person.

The major aquifer currently used lies at a depth of between 60 and 400 meters and is heavily over-utilized. There are about 630 wells in the Federal District alone; all are overexploited and have an average life expectancy of 30 years. Current extraction from the aquifer is around 17,000 liters/second, while its natural recharge capacity is only 8000-9000 liters/second. It is believed that the deep aquifer could be capable of supplying approximately 5000 liters/second.

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Sep 082014
 

In mid-August 2014, this significant fissure (see image) appeared near the city of Hermosillo in northern Mexico, with some press reports opting for headlines such as “The Earth Splits Open”:

fissure-hermosillo-eyewitness-news

While many press reports, especially those in English, tried to link this fissure to faulting and earthquake movements, others were more cautious, saying it was caused by movement of water underground followed by subsidence. Which version is correct? Probably neither is completely correct, since geography often fails to provide a single, definitive reason for things!

The crack is about 1000 meters (two thirds of a mile) long and up to 7 or 8 meters wide and 10 meters deep. While some press reports erroneously claimed that the crack extended across the main, paved, highway #26 between Hermosillo and the coast, its location was actually some distance away from the main highway. The road shown in the image above is a rural, unpaved road about 80 kilometers (50 miles) west of Hermosillo, in an area of farmland, some of which is irrigated.

Could the fissure have been formed by faulting associated with earth tremors or an earthquake? If this was the cause, the fence line, and the line taken by the road would have shifted position and no longer be straight. The image clearly shows that the road has been severed, but provides no evidence that the two sides have shifted position. Indeed, a close-up view confirms that even the existing fence remains in place:

fissure-hermosillo-fence-line

The available evidence therefore rules out faulting (or earth tremors or earthquakes) as the cause of the crack.

Could the fissure have been caused by an underground flow of water followed by subsidence (the collapse of overlying rocks)? This certainly looks more likely though it is hard to imagine significant underground flows of water in an area that is as flat as this. On the other hand, this is (a) an area of newly constructed irrigation ditches and ponds, and (b) it received heavy rainfall a few days before the crack was reported.

In all probability, the fissure began as a deep but very narrow “subsidence fissure” where differences in irrigation (or in water extraction) caused some parts to be much wetter than others. The soil and rock particles in wetter areas would tend to expand, while those in drier areas would tend to contract. Such differences could lead to the formation of small initial fissures.

Once the fissure had been started, localized heavy rains and the resulting overland flow could then result in streams flowing (temporarily) in these initial fissures. The moving stream water would rapidly widen and deepen the fissures into the scale of crack shown in the photos. The initial fissure may have been formed several years before this widening process occurred.

For a more detailed look at the evidence for this fissure’s formation (and its true location), see Debunked: The Earth Splitting Open – Giant Crack in Mexico.

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Recent progress in waste water treatment in Mexico

 Mexico's geography in the Press  Comments Off on Recent progress in waste water treatment in Mexico
Aug 252014
 

Two wastewater treatment plants have been in the news recently. The first is the $230 million Agua Prieta wastewater treatment plant, located north of Guadalajara in Jalisco, which was formally inaugurated last month. It is the first stage in a plan to restore the heavily polluted Santiago River back to health. The Santiago is the outflow from Lake Chapala and receives pollutants from the industrial zone of El Salto outside Guadalajara. The initial capacity of the Agua Prieta plant is 6,500 liters/second, almost all of which is returned to the river after treatment.

The plant was built by a consortium led by ICA subsidiary Conoisa, Atlatec, and Servicios de Agua Trident under a 20-year concession. President Enrique Peña Nieto claims on his government webpage that, “Integrated, sustainable water management is a government priority. The challenge is even greater because almost 50% of the wastewater returned to the environment does not undergo any form of treatment… The Agua Prieta Wastewater Treatment Plant in Zapopan… [will] improve the quality of life of 3.3 million inhabitants in the metropolitan area of Guadalajara… It will treat 82% of the wastewater in the area, and 100% when the complementary sewage works are completed.”

agua-prieta-wastewater-According to government figures, waste water treatment coverage at the national level is currently 50.3%, with a 2018 target of 63%. Agua Prieta has raised national coverage to 53.3%, and will boost it to 54.3% once the plant is operating at full capacity and treating 8,500 liters/second of wastewater. At the state level, Jalisco is now treating 32% of its wastewater.

The Agua Prieta plant is currently the largest of its kind in Mexico and is powered by biogas derived from the wastewater sludge. However, an even larger plant is under construction, in the state of Hidalgo in central Mexico. The Atotonilco Wastewater Treatment Plant is being built by a consortium, including Mexican construction companies ICA and IDEAL, Mitsui subsidiary Atlatec and Spanish firm Acciona Agua, that won the concession to design, build, and operate this plant for 22 years, at which point the plant will be transferred to federal ownership. Work began in 2010 and is due to be completed by 2015.

The Atotonilco Wastewater Treatment Plant will be the largest wastewater plant in Latin America and one of the largest in the world, with a biological treatment capacity of 23,000 liters/second (1.99 million m3/day). The wastewater treatment is performed by a series of conventional processes, with an additional chemical process during the rainy season. Treated waters from this plant are already being used in agriculture without any additional cleaning steps. The plant is self-sufficient in terms of energy usage, since it converts the methane offgas from the wastewater sludge into electrical energy.

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UNESCO appoints Mexico to oversee its International Hydrological Program

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Jul 102014
 

Mexico has been chosen to head the inter-governmental council that oversees UNESCO’s International Hydrological Program (IHP). The IHP is the only inter-governmental program of the U.N. system devoted to water research, water-resources management, and education and capacity building.

A joint statement issued by Mexico’s Environment Secretariat and Foreign Relations Secretariat says that David Korenfeld, the director of Mexico’s National Water Commission (Conagua) has been named the council’s president for the next two years. In his acceptance speech, Korenfeld called for “greater synergy between decision makers and specialists to combine theory and practice” and stated that “significant challenges remain [in the water sector], including integral basin management, application of the human right to water and water security and sustainability in the context of climate change.

Korenfeld said that one of the IHP’s main objectives must by to strengthen “a confluence of science, technology and public policy aimed at reducing the social and environmental vulnerability of emerging and developing countries amid the challenges of climate change.”

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Mexicans drink more bottled water per person than anywhere else in the world

 Updates to Geo-Mexico  Comments Off on Mexicans drink more bottled water per person than anywhere else in the world
May 032014
 

Mexicans are the world’s largest consumers of bottled water, both in individual small bottles (1.5 liters or less) and in garrafones (large, 20-liter bottles).

The main reason is a lack of confidence in the purity of public water supplies, resulting in part from perceived inefficiencies in how city water systems are managed and maintained. These concerns may be valid in some parts of Mexico, but are certainly not the case in all areas. Other factors resulting in a high acceptance of bottled water are the convenience, Mexico’s warm climate, and the vigorous publicity and advertising campaigns carried out by bottled water companies. It does not help that consumer groups repeatedly express concerns even about the quality of water in garrafones, claiming that some companies apparently take insufficient precautions to prevent its contamination.

For its part, the National Water Commission repeatedly claims that the problem of water quality is not due to the main distribution lines in Mexico, but to problems at a local level, in the final stages of the network between supply and consumers.

garrafon

Typical 20-liter garrafon

According to Euromonitor International, bottled water consumption in Mexico in 2013 averaged 186.7 liters/person, well ahead of Italy (175.1 liters/person), Nigeria (163.1), Turkey (147.7) and Spain (143.2). [Note that an earlier estimate in 2010 by Beverage Marketing Corporation put per person consumption of bottled water in Mexico at 234 liters a year, with equivalent figures for Italy, Spain and the USA of 191 liters, 119 liters and 110 liters respectively; the difference from 2010 to 2013 is almost certainly due to methodological differences].

Mexico consumes about 13% of all bottled water sold in the world! The only countries consuming more bottled water (in total volume) than Mexico were the much more populous countries of the USA, China and Nigeria.

Bottling water is a highly profitable business. The cost of 1,000 liters from the tap is 25 pesos (about 2 dollars); the same water, sold in bottles, is worth between 6000 and 8500 pesos (450 to 650 dollars).

The bottled water market in Mexico has grown from 6.5 billion dollars in 2009 to 10.4 billion in 2013, according to Euromonitor.  It is dominated by three foreign firms: Danone (France), Coca-Cola (USA) and PepsiCo (USA). Between them, they supply 82% of the market, according to a Euromonitor report, with the three leading brands being Bonafont (Danone) which accounts for 38% of the market, followed by Ciel (Coca-Cola) which has a 25% share and Epura (PepsiCo) 19%.

The cost of bottled water in an average Mexican household is considerable. For instance, assuming an average consumption of 15.55 liters/month/person, and that all water is bought in 1-liter bottles (which cost about 8 pesos each), then the monthly cost per household would be close to 500 pesos (38 dollars).

An industry dominated by four multinationals

Inside the Bottle: An Exposé of the Bottled Water Industry, a book by Canadian activist Tony Clark, provides a vivid and disturbing portrayal of how, worldwide, four big companies – Nestlé, PepsiCo, Coca-Cola and Danone – dominate the bottled water industry. As summarized by infinitewaterinc.com, the book examines several key issues of public concern about the operations of these companies, including how they:

  • pay little or nothing for the water they take from rural springs or public systems;
  • turn ‘water’ into ‘water’ through elaborate treatment processes;
  • produce a product that is not necessarily safer then, nor as regulated as, tap water;
  • package it in plastic bottles made of environmentally destructive toxic chemicals;
  • market it to an unsuspecting public as ‘pure, healthy, safe drinking water’; and
  • sell it at prices hundreds, even thousands of times more costly than ordinary tap water.

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World’s longest underground river flows deep beneath the Yucatán Peninsula

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Feb 102014
 

In January 2007, the world’s longest underground river was reported from Mexico’s Yucatán Peninsula. [Prior to that date, the honor was held by the Puerto Princesa Subterranean River in the Philippines]

The Sac Actun (“White Cave”) river system in the Yucatán Peninsula wanders for 153 km (95 miles) through a maze of underground limestone caves. It took British diver Stephen Bogaerts and his German colleague Robbie Schmittner four years to explore the caverns using underwater scooters and specially rigged gas cylinders, before they finally discovered a connection between the Yucatán region’s then second- and third-longest cave systems, known respectively as Sac Actun and Nohoch Nah Chich (“Giant Birdcage”). Following the discovery of a link, the entire system is now known as Sac Actun. The system has a total surveyed length (including dry caves) of 319 kilometers (198 mi), making it the longest cave system in Mexico, and the second longest worldwide. [The longest is the dry Mammoth Cave System, Kentucky, USA, which measures 643.7 km (400 mi) in length].

Sac-Actun cave system

Sac-Actun cave system

Vying with Sac Actun for the title of longest surveyed underwater cave system is the nearby Sistema Ox Bel Ha (“Three Paths of Water”), also in the Tulum municipality of Quintana Roo. As of August 2013, surveys had measured 256.7 kilometers (159.5 mi) of underwater passages.

The underground passages and caverns of the Yucatán Peninsula have been a favored site for cave explorers for decades. Formal mapping of the systems has taken more than 20 years of painstaking work. Access to the systems is via the hundreds of sinkholes (cenotes) that litter the surface of the Peninsula. The Sac Actun system alone includes more than 150 cenotes.

Water management was critical to the Maya as they developed their advanced civilization in this area, a region with very limited surface freshwater. Many of the cenotes in the Yucatán Peninsula have archaeological importance and were utilized by the Maya for ceremonies. Perhaps the best-known (and most visited) cenote is the Sacred Cenote (cenote sagrado) at the archaeological site of Chichen Itza.

The caverns of the Yucatán Peninsula were formed as a result of the slow solution of limestone over thousands of years by percolating, slightly acidic, rainwater. In some cases, cave formations, such as stalactites and stalagmites, have later grown in the caves, formed drip-by-drip from the slow deposition of calcium carbonate from calcium-saturated ground water.

Because the average elevation of the Yucatán Peninsula is only a few meters above sea level, the water in many of the caves is “layered”, with a lens of freshwater overlying a layer of salt water. Rainwater that soaks into the ground becomes ground water, which then moves slowly along the watertable to eventually reach the ocean.

Cave researchers are worried that tourist developments in the Yucatán Peninsula will have adverse impacts on underground water systems, both in terms of water quantity (because of the amounts of fresh water extracted for domestic and tourist use) and in terms of water quality, because even point sources of water pollution (such as excess fertilizers from a golf course) could contaminate underground water supplies over a wide area.

Want to read more?

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Water management progress in the Lerma-Chapala basin

 Books and resources  Comments Off on Water management progress in the Lerma-Chapala basin
Jan 112014
 

The Lerma-Chapala Basin (see map) is one of Mexico’s major river systems, comprising portions of 127 municipalities in five states: México, Querétaro, Michoacán, Guanajuato and Jalisco.

The basin has considerable economic importance. It occupies only 2.9% of Mexico’s total landmass, but is home to 9.3% of Mexico’s total population, and its economic activities account for 11.5% of national GDP. The basin’s GDP (about 80 billion dollars/year) is higher than the GDP of many countries, including Guatemala, Costa Rica, Honduras, Paraguay, Bolivia, Uruguay, Croatia, Jordan, North Korea and Slovenia.

Lerma-Chapala Basin

The Lerma-Chapala Basin. Click map to enlarge. Credit: Tony Burton / Geo-Mexico

Given this level of economic activity, it is probably not surprising that the pressures on natural resources in the basin, especially water, are enormous. Historically, the downstream consequence of the Lerma Basin’s agricultural and industrial success has been an inadequate supply of (heavily polluted) water to Lake Chapala.

Following decades of political inactivity or ineffectiveness in managing the basin’s water resources, solid progress finally appears to have been made. Part of the problem previously was a distinct lack of hard information about this region at the river basin scale. The statistics for such key elements as water usage, number of wells, replenishment rates, etc. were all (to put it politely) contested.

Fortunately, several scientific publications in recent years have redressed the balance, and the Lerma-Chapala Basin is now probably the best documented river basin in Mexico. This has allowed state and federal governments to negotiate a series of management agreements that are showing some positive signs of success.

The first of these key publications was “The Lerma-Chapala Watershed: Evaluation and Management“, edited by Anne M. Hansen and Manfred van Afferden (Klewer Academic/Plenum Publishers, 2001). This collection of articles featured contributions from researchers in several universities and research centers, including the University of Guadalajara, Mexican Institute of Water Technology, Autonomous University of Guadalajara, Baylor University, the Harvard School of Public Health and Environment Canada. Click here for my comprehensive description and review of this volume on MexConnect.com.

Perhaps the single most important publication was the Atlas de la cuenca Lerma-Chapala, construyendo una visión conjunta in 2006. Cotler Ávalos, Helena; Marisa Mazari Hiriart y José de Anda Sánchez (eds.), SEMARNATINE-UNAM-IE, México, 2006, 196 pages. (The link is to a low-resolution pdf of the entire atlas). The atlas’s 196 pages showcase specially-commissioned maps of climate, soils, vegetation, land use, urban growth, water quality,  and a myriad of other topics.

More recently, a Case Study of the Lerma-Chapala river basin: : A fruitful sustainable water management experience was prepared in 2012 for the 4th UN World Water Development Report “Managing water under uncertainty and risk”. This detailed case study should prove to be especially useful in high school and university classes.

The Case Study provides a solid background to the Lerma-Chapala basin, including development indicators, followed by a history of attempts to provide a structural framework for its management.

In the words of its authors, “The Lerma Chapala Case Study is a story of how the rapid economic and demographic growth of post-Second World War Mexico, a period known as the “Mexican Miracle”, turned into a shambles when water resources and sustainable balances were lost, leading to pressure on water resources and their management, including water allocation conflicts and social turbulence.”

On a positive note, the study describes how meticulous study of the main interactions between water and other key development elements such as economic activity and social structures, enabled a thorough assessment on how to drive change in a manner largely accepted by the key stakeholders.

The early results are “stimulating”. “Drawbacks and obstacles are formidable. The main yields are water treatment and allocation, finances, public awareness, participation and involvement. The main obstacles are centralization, turbid interests, weak capacity building, fragile water knowledge; continuity; financial constraints; and weak planning.”

Sustainable water usage is still a long way off. As the Case Study cautions, “There is still much to do, considering the system Lerma-Chapala responds directly to a hydrologic system where joint action and especially abundant involvement of informed users is required, to achieve sustainable use of water resource.”

One minor caveat is that the Case Study does not offer full bibliographic reference for all of the maps it uses, which include several from the previously-described Atlas de la cuenca Lerma-Chapala, construyendo una visión conjunta.

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The city of León in Guanajuato uses Google Earth to monitor its water usage

 Mexico's geography in the Press  Comments Off on The city of León in Guanajuato uses Google Earth to monitor its water usage
Dec 212013
 

León, in the state of Guanajuato, is a prosperous industrial city (population 1.6 million), which built its wealth by processing animal hides obtained from the surrounding ranching areas into all manner of leather goods, especially clothing, accessories and shoes, the range of which goes from casual to ultra-fashionable. León does not just have shoe stores, it has shoe shopping centers!

Founded in 1576 and named for a province in Spain, the city became an important colonial center, well positioned on the main trading routes. It later became important for anti-colonial sentiment. Brothers Juan and Ignacio Aldama, born here in the eighteenth century, became key figures in the Independence movement led by Father Miguel Hidalgo. Shortly after Independence, the city’s shoe industry started, introduced by skilled craftsmen from Puebla.

Like any wealthy Mexican city, León has lots of old buildings, including the eighteenth century Cathedral with its fine choir stalls and the Nuestra Señora de los Angeles church, embellished by the interesting carvings of a native craftsman. The impressive Town Hall, with its elaborate façade, is a nineteenth century addition, as is the Manuel Doblado Theatre, designed by José Noriega who also had a hand in building theatres in several other cities in the region, including Guanajuato, Aguascalientes and San Luis Potosí.

leon-agua-monitoreoThe city would have even more old buildings today were it not for the disastrous flood of June 1888 when torrential downpours caused the Río Gómez to burst its banks. A wall of water and debris swept away more than 2000 homes, causing 200 fatalities and making 20,000 homeless. Major engineering works shortly afterwards have ensured that the city is now safe from future events of this kind.

The city has grown into one of Mexico’s most important industrial centers. The position of León has been key to its success. The city is located in central Mexico, close to the major urban areas of Mexico City, Querétaro and Guadalajara. On a broader scale, it is close to the major export markets of the USA, Canada and Central America. Market proximity is enhanced by an excellent communications network, including good road and rail links, easy access to several major airports, and to seaports such as Manzanillo.

Like most cities in central Mexico, one of León’s most pressing problems is how to ensure that its residents and industries have an adequate supply of potable water, even though the city was rated #1 in the country in terms of overall performance in this regard in the 2011 report “Water Management in Mexican Cities”.

In order to monitor the city’s water usage more effectively, engineers from the León Potable Water and Sewerage System (SAPAL) have introduced a sophisticated software system that provides real time data about the city’s water network and wells. It enables the engineers to overlay data like address, owner, account status, and water consumption onto a series of screen connected to Google Earth.

The system was developed in-house by local engineers, starting more than a decade ago, at a fraction of the cost of purchasing a similar system from an external provider. The León system is already being closely studied by water experts from other cities and countries.

SAPAL’s Control and Monitoring Center has a video wall, measuring 7.5 by 2 meters, with 24 LED screens. The center functions 24 hours a day, monitoring details of water distribution for more than 9000 data points, including wells, pipelines and holding tanks.

According to Agustín Báez, the city official responsible for SAPAL operations, the objective is “to have measurement from point of extraction to final use” since “what is not measured is not controlled.”

Sources:

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Mexico City explores deep water aquifer

 Mexico's geography in the Press, Updates to Geo-Mexico  Comments Off on Mexico City explores deep water aquifer
Dec 092013
 

Background: The Valley of Mexico is an interior basin about 9000 square km in area. The basin floor sits at an elevation of 2200 meters above sea level and is surrounded by mountains that rise up to more than 5000 meters above sea level. It receives around 700 mm of rainfall a year, with a rainy season from late May to September.

The basin was originally the site of several lakes and marshes, and much of it is underlain by lacustrine sediments up to 100 m thick, beneath which are alluvial sediments up to 500 m thick (see geological cross-section below). These sediments are interstratified with layers of volcanic basalt. Beneath the alluvial sediments are 100 m to 600 m of volcanic deposits, which form the principal Mexico City aquifer (found about 500 m to 1000 m below Mexico City).

As Mexico City has grown, and water demands have increased, this main aquifer has been greatly overexploited, leading to a drop in the level of the water table underground, accompanied by ground subsidence that has had serious consequences for Mexico City:

Feasibility study of a deep aquifer

The National Water Commission (CNA) and Mexico City Water System (SACM) are undertaking a 3-year, 23-million-dollar feasibility study to assess the potential of an aquifer that lies more than 2000 meters below Mexico City. (Our earlier, initial report about this aquifer is here).  The project includes experts from Pemex, CFE and UNAM’s Institute of Geophysics.

Schematic stratigraphy of the southern portion of the Basin of Mexico.

Schematic stratigraphy of the southern portion of the Basin of Mexico.
Source: Adapted from Mooser, 1990.

Initial exploratory wells have shown that the deep aquifer’s water quality is superior to that currently derived from the overexploited shallower wells that extend to depths of around 800m.

It is hoped that the feasibility study will confirm that water from the deep aquifer could be an additional viable source of freshwater for the city. Assuming the deep aquifer is hydrologically independent of the shallower aquifers, this  would not only reduce the need to pump water from the shallower aquifers, but would also avoid the ground subsidence resulting from continued shallow-water extraction. The feasibility study will assess whether or not the deep water aquifer is “fossil” water or is still being recharged from precipitation and underground throughflow. If it is being recharged, the experts will calculate its recharge rate to determine the aquifer’s maximum sustainable yield. (The maximum sustainable yield is the “additional groundwater output from the system which will cause minimal and acceptable levels of stress to the ecosystem with maximum benefits to the society and to the economy”).

The first test well is likely to be sunk in the Magdalena Mixhuca Sports City area, in the eastern part of Mexico City.

This potential deep aquifer source of freshwater could play a vital part in ensuring that future generations of Mexico City residents have a dependable and sustainable water supply.

Mexico’s consideration of utilizing deep water aquifers runs counter to the prevailing wisdom in the US where it has long been argued that deep water aquifers will be too costly to utilize for fresh water, will never be used, and are therefore more useful as a repository for waste and can be intentionally polluted.

As a result, as this Huffington Post article explains, “policy-makers often exempt these deep aquifers from clean water protections and allow energy and mining companies to inject pollutants directly into them.”  The article adds that, “the U.S. Environmental Protection Agency has issued more than 1,500 permits for companies to pollute such aquifers in some of the driest regions. Frequently, the reason was that the water lies too deep to be worth protecting.”

References:

Mooser, F. 1990. “Estratigrafía y estructura del Valle de México en el subseulo de la cuenca del Valle de México y su relacíon con la Ingeniería de cimentaciones, a cinco anos del sismo”, in Revista de la Sociedad Mexicana de Mecánica de Suelos. Mexico, D.F.

For a detailed description of Mexico City’s shallower aquifer and its exploitation, see Mexico City’s Water Supply: Improving the Outlook for Sustainability (1995) (viewable online or register for a free download)

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Resources about the geography of chinampas, an ancient form of sustainable agriculture

 Books and resources  Comments Off on Resources about the geography of chinampas, an ancient form of sustainable agriculture
Sep 302013
 

This post describes some of the many online resources about chinampas, one of Mexico’s ancient and most important indigenous forms of sustainable agriculture.

For photos, the best starting point is Dr. Jason Turner’s site about chinampas which includes an extensive bibliography about chinampas as well as several “Virtual Field Trips” (photo sequences). Even though these photo sequences often lack any accompanying descriptions or captions, they cover a wide range of ideas, and are organized in self-explanatory groups such as:

For an article describing a recent tour of a working chinampa in Xochimilco’s Ecological Reserve. illustrated with great photos, try Touring Xochimilco’s farms with De la Chinampa written by Lesley Téllez (self-described food writer with a “deep love for Mexican food and culture”) on her blog “The  Mija Chronicles”.

Youtube also has a variety of chinampa-related resources. In English, the best introduction is Discovery Atlas – Mexico: Xochimilco which provides a good background to the history and covers the basics.

Two Spanish-language Youtube resources provide valuable additional information. Each video lasts about 5 minutes, but neither video has English language subtitles.

The first is Divina Ciudad: De la chinampa a la mesa which looks at one specific project designed to help raise public awareness and aid the conservation of the remaining chinampas in Xochimilco, on the south-eastern outskirts of Mexico City. This project supplies consumers with fresh produce grown on the chinampas in Xochimilco or sourced from within 150 km. See the project’s website – De La Chinampa – for more information.

The second Spanish language video is Profeco TV Reporte Especial: Productos de la Chinampa, un ejemplo de consumo sustentable, This video, made by the federal consumer protection agency Profeco, explains how the produce grown on the chinampas is pesticide-free and relies on sustainable production methods. It calls on viewers to “learn more about the method and help ensure that chinampas do not disappear.”

Book (Spanish)

  • Rojas R., Teresa (Coord) 1995. Presente, pasado y futuro de las chinampas. Mexico DF: Ciesas/Patronato del Parque Ecológico de Xochimilco A.C. This is a collection of 25 papers presented at a 1990 international conference in Mexico City.

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