Archaeological discoveries

Ingenious technique of the Mayas to filter water

In the city of Tikal, the Mayans had their own way of filtering water. An ingenious technique with compounds still used today for the same purpose.

A temple rises above the rainforest in the ancient Mayan city of Tikal.

It is not uncommon to be amazed by the extent of knowledge of civilizations that have disappeared. Researchers from the University of Cincinnati (United States) have just described, on October 22, 2020 in the journal Scientific Reports , an ingenious technique that the Maya used to filter water. Indeed, zeolite, a microporous crystal, was found in one of the largest Mayan drinking water storage facilities.

Drinking water tanks of paramount importance

The Maya were forced to build reservoirs to provide a reliable and sustainable source of drinking water during times of drought in what is now northeastern Guatemala. Like others, the Corriental Reservoir (one of the largest, storing approximately 58,000,000 L) in the city of Tikal was therefore of paramount importance. If blue gold was so precious for this American civilization, it is also because "Tikal and other Mayan cities were built on porous limestone, which made access to water easy Drinking water difficult to obtain for much of the year, especially during seasonal droughts ", notes in a press release the University of Cincinnati.

Researchers have now discovered that the Maya used a system to filter the water in this important reservoir. They used quartz and zeolite (a crystalline compound of silicon and aluminum) to create a sort of molecular sieve to trap harmful microorganisms, nitrogen-rich compounds, heavy metals such as mercury and other toxins.

It is not uncommon to be amazed by the extent of knowledge of civilizations that have disappeared. Researchers from the University of Cincinnati (United States) have just described, on October 22, 2020 in the journal Scientific Reports , an ingenious technique that the Maya used to filter water. Indeed, zeolite, a microporous crystal, was found in one of the largest Mayan drinking water storage facilities.

Drinking water tanks of paramount importance

The Maya were forced to build reservoirs to provide a reliable and sustainable source of drinking water during times of drought in what is now northeastern Guatemala. Like others, the Corriental Reservoir (one of the largest, storing approximately 58,000,000 L) in the city of Tikal was therefore of paramount importance. If blue gold was so precious for this American civilization, it is also because "Tikal and other Mayan cities were built on porous limestone, which made access to water easy Drinking water difficult to obtain for much of the year, especially during seasonal droughts ", notes in a press release the University of Cincinnati.

Researchers have now discovered that the Maya used a system to filter the water in this important reservoir. They used quartz and zeolite (a crystalline compound of silicon and aluminum) to create a sort of molecular sieve to trap harmful microorganisms, nitrogen-rich compounds, heavy metals such as mercury and other toxins. "While a stand-alone sand-sized coarse crystalline quartz filtration system would have been able to clarify the water, it would have had no effect on removing harmful microbes or insoluble or soluble toxins Zeolite was a crucial part of the Corriental water purification system “, underlines the American study, demonstrating all the ingenuity of this civilization. “It is probably thanks to a very intelligent empirical observation that the ancient Mayans saw that this particular material was associated with clean water ", said Nicholas Dunning, co-author of this new study.

This system, which could still work today, was discovered more than 2,000 years ago by the Mayas. However, not all tanks were equipped with them. Indeed, a previous study reported on Sciences et Avenir provided evidence of significant pollution of certain drinking water reservoirs. The identified mercury and algae made the site's liquid unfit for consumption.

READ. Extreme droughts are the cause of the collapse of the Maya

Other techniques used elsewhere in the world

The researchers identified the provenance of the quartz and the zeolite by analyzing the sediments found in the old reservoir. Their trace was found nearly 30 kilometers northeast of the town of Tikal. These compounds were therefore imported at least to serve as a filter. Eventually, the system, whose exact functioning remains hypothetical, was destroyed for some unknown reason and has not been restored. It is possible that the Maya then no longer had access to the necessary raw materials.

The Tikal archaeological record includes the oldest known zeolite water purification system which was developed at a time when cultures elsewhere in the world were experimenting with other water purification methods such as boiling, cloth colanders, porous ceramic containers and sand sieves, say the researchers.