MesoAmericas & Beyond

Partial reprint from https://www.sciencealert.com/an-ancient-maya-civilisation-had-surprisingly-effective-water-filtration-system

Several ancient civilisations, including the Greeks, Egyptians, and Romans, filtered their water. Sanskrit writings dating back to 2,000 BCE also mention water treatment methods. Now, archaeologists have discovered the Maya of Central America did too – and their water filtration system was incredibly effective.

In a reservoir in what was once the major Maya city of Tikal, the ruins of which crumble in a rainforest in present-day Guatemala, archaeologists have found zeolite and quartz – minerals that are not local to the area, and which are both effective at helping remove contaminants such as microbes, heavy metals, and nitrogen compounds from water.

So effective, in fact, that they are both used in water filtration systems today.

“What’s interesting is this system would still be effective today, and the Maya discovered it more than 2,000 years ago,” said anthropologist Kenneth Barnett Tankersley of the University of Cincinnati.

Zeolite, in particular, is interesting. It’s a natural crystalline compound of silicon and aluminium, linked via shared oxygen atoms to form an open crystal lattice. It has excellent absorption and ion exchange properties, which makes it very effective at filtering water.

The discovery was made in the Corriental reservoir, an important source of drinking water for the residents of Tikal, and one of the largest drinking water reservoirs in use by the Maya for over a thousand years. Mixed in among the sediment at the bottom of the reservoir, the team found what they were looking for: zeolite and coarse quartz sand.

The zeolite was found only in the Corriental reservoir. There’s no way it could have just happened to be there when the reservoir was dug.

In fact, the team believes that the mineral was quarried from a site some 30 kilometres (18 miles) northeast of Tikal. There, volcanic rock forms an aquifer known to produce exceptionally clear water. University of Cincinnati geographer Nicholas Dunning was familiar with the area after previously conducting fieldwork there.

“A lot of people look at Native Americans in the Western Hemisphere as not having the same engineering or technological muscle of places like Greece, Rome, India, or China. But when it comes to water management, the Maya were millennia ahead.”

The research has been published in Scientific Reports.