Water access good but it must be good water

Cost of safe drinking water a heavy burden for many and impossible for others

by Todd D. Stong, originally posted on May 21, 2016


Why does Mexico have the highest per-capita consumption of bottled water in the world?

If a community is receiving public water and that supply is in sufficient quantities to sustain normal living, say at least 100 liters per person per day, then the question may be, is the water safe to drink?

It seems clear that most Mexicans (80%-plus) are buying commercial bottled water, two to three liters a day, at a cost that is 200-350 times more than public water. For a peso one can buy about 0.8 to 1.3 liters of bottled water or have the government provide about 350 liters of public water.

This added cost of 5,000-6,000 pesos per year for bottled water for a family as compared to 1,000 pesos a year for public water is a serious burden for the poor, the 55 million Mexicans who live below the poverty line. Clearly the motive for buying bottled water is because people feel that public water may not be not safe.

For the 20% of the nation that cannot afford bottled water, potentially impure, untreated public water may be their only choice. While Mexico has established excellent national standards for water quality that basically address acidity, various minerals and bacteria, it is only bacteria that appears to be monitored, perhaps annually, and that is only at the village well.

To assure that water from a well arrives safely at each home in a community, normal practice is to add chlorine (one to five parts per million). This not only destroys bacteria that may originate at the village well but a residual will continue to act upon any bacteria encountered in the pipes.

It is typically desirable that there be a chlorine residual (0.1-0.5 parts per million) once the water arrives at a home to guarantee it is still free of bacteria.

While Mexico reports that over 90% of pubic water is treated with chlorine, the reality in rural communities is that less than 20% of well water is so treated and that no residual chlorine may be detected at the home’s faucet. The key reason is often that people, due to a lack of education or superstition, object to treating the water with chlorine.

While in Africa once a native whispered in my ear that chlorine was the reason I was white and they, of course, did not wish that to happen to them. In Mexico the added challenge in rural area is that chlorine and injection pumps are often not provided or maintained by the government, or it is too old to be effective.

Another reason for not drinking well water is that there are very seldom any mineral tests by the state. Such tests, perhaps done each three years, may find evidence of various hazards especially in regions with volcanic rock and soil. These hazardous substances (arsenic, lead and nitrogen-ammonia, for example) can have a serious impact (delayed mental development and retardation) for children under age six.

Possible actions?

1. Rein in excessive profits from the sale of over 250 million pesos per day by politically powerful international bottlers. Given the two to four pesos it costs to produce a 19-liter bottle of water, plus a delivery charge of four to six pesos, to sell it at 15 to 25 pesos is too much (50%-400% profit).

2. Educate the public on the need for water chlorination and chlorine’s natural use by the body.

3. Assure the means for adding chlorine to water reaches and is applied at village well sites.

4. Require that all public and private water tests include all minerals of interest for piped and bottled water and be posted on a designated Internet site within 30 days.

5. Add to Mexico’s current promise to its 120 million citizens of access to water the further promise that their water will be pure and safe. Begin with the rural population that is least able to purchase bottled water.

Dr. Todd D. Stong, a licensed professional civil engineer (USA), has served for the past 14 years in Jalisco state as a volunteer engineer adviser to local area governments. His major focus has been on the water and wastewater issues in 42 villages around Lake Chapala as well as job creation. Previously he served for 44 years in the U.S. government and private industry with half his career overseas in infrastructure construction and municipal engineering and half in directing scientific laboratories and research in the U.S. He can be contacted at todd.stong@aridgroup.com.

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