| | | Editorials | Environmental | September 2009
Mexico's Goal: Not a Drop Wasted Emilio Godoy - IPS/IFEJ go to original September 20, 2009
| Geomembranes to collect and filter rainwater. (Emilio Godoy/IPS) | | San Felipe del Progreso, Mexico - In his novel "México sediento" (Mexico in a Drought), author Francisco Moreno postulated that drought would lead to war in 2010, just as water shortages helped trigger the fight for Mexico's independence from Spain in 1810 and the Mexican Revolution in 1910.
Although lack of water is nothing new in Mexico, today the country is suffering a severe crisis as a result of the depletion of groundwater and scant rainfall.
In Mexico City, one of the hardest-hit areas, the idea is to make use of what rain does come, which otherwise goes to waste. Some 17 cubic metres of rainwater go down the drain every second.
A good example of utilising rain is under way in the municipality of San Felipe del Progreso, 150 km from the capital, where a rainwater collection and purification plant is operating.
With technology developed by the International Centre for Demonstration and Training in Rainwater (CIDECALLI) of the Postgraduate College of Texcoco, and with funding from private donations, the non-governmental Pro Zona Mazahua Sponsorship invested 1.5 million dollars in the project launched in 2006 to supply clean water to poor rural and semi-rural areas and to prevent gastrointestinal diseases.
"It has been difficult to introduce the water that we purify, because people have gotten used to drinking soft drinks," Manuel Figueroa, head of the plant, told this reporter.
The site has a slope with a geomembrane that channels rain to two enormous basins with more geomembranes, low-permeability sheets made from plastic resins. They filter out particulate matter from the water, which passes to a tank, from which it flows into purification machines and into 19-litre bottles. This final phase takes five hours.
The installed capacity is five million litres, and 4,000 litres are processed daily, of which 2,500 are used for human consumption. The rest goes to irrigating the plant nursery of forest species being grown as part of the project.
The project's brand, "Más-Agua", is distributed to rural homes and schools in the area, populated by Mazahua Indians. The price varies between .75 and 1.10 dollars per bottle.
"We began to look skyward and we asked ourselves why we weren't taking advantage of rainfall, which is a valuable resource and easy to treat and make potable. Our project is 30 years old and they asked me when it would be viable. I responded that it would happen when we reached a crisis. That moment has come," Manuel Anaya, CIDECALLI coordinator, said in an interview for this report.
A group of professors from the Postgraduate College, specialised in agricultural sciences, and from the autonomous universities of Chapingo and Antonio Narro, created CIDECALLI in 2004.
Mexico City proper, home to around 12 million of the 20 million people who live in Greater Mexico City, consumes 33 cubic metres of water per second. Due to leaks in the pipes, every year around 150 million cubic metres are lost. Water from the city's aquifers is consumed at a pace of 55.5 cubic metres per second.
Given the lack of rain in the last three months, the government's National Commission on Water and the water system in the capital have reduced the supply. Officials warn that if the crisis continues, the capital will have no water in February 2010.
The rainwater collection systems are "replicable, economical, accessible and give good results," said Enrique Lomnitz, director of the non-governmental International Renewable Resources Institute-Mexico.
Within the "Urban Island" project, Lomnitz and his team have set up five collection systems in homes in a low-income district in southern Mexico City. The families provide the materials and the project sets it up, free of cost.
The system involves a pre-filtration mechanism, a tank where chlorine disinfects the water, and a filter, for a total cost of 115 to 190 dollars. Each square metre of rooftop can supply one litre of water.
"We are concentrating our efforts on a specific site in order to create a prototype on a neighbourhood scale, one that can be monitored and easily managed," explained Lomnitz, an industrial designer with a degree from the Rhode Island School of Design in the United States.
Faced with a worsening crisis, the non-governmental Centre of Research for Development (CIDAC) designed a pilot project for rainwater collection at 120,000 houses, equivalent to 10 percent of the city's households.
CIDAC proposes that the governments of the capital and of the state of Mexico finance the initiative, whose cost per house is 350 dollars, and which would lead to savings of approximately 7.2 million cubic metres of water annually.
The use of rainwater collected by households in tanks has proved successful in other arid regions of the world, such as Brazil's impoverished Northeast.
The promoters of "Más-Agua" purchased a machine that fills 48 half-litre bottles per minute. But San Felipe del Progreso, a city of 100,000 people, faces the same lack of rainfall as the rest of the country. And if water doesn't fall from the sky, the factory won't have anything to purify. The alternative will be, then, to process water from the area's groundwater and wells.
But, if done right, the water collected during rainfall is enough to cover the dry months, from November to May.
This story is part of a series of features on sustainable development by IPS - Inter Press Service, and IFEJ - International Federation of Environmental Journalists, for the Alliance of Communicators for Sustainable Development (www.complusalliance.org). |
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