This Q&A originally appeared in WQP March 2021 issue as "Ancient Maya Filters"
A team of researchers from the University of Cincinnati found evidence of a water filtration system at the Corriental reservoir in Guatemala, which served ancient Maya civilizations in the city of Tikal. WQP Managing Editor Lauren Del Ciello spoke with Dr. Kenneth Tankersley, associate professor of anthropology and geology at the University of Cincinnati, about the process of discovering the system that used zeolite to filter contaminants and provide the community with high quality drinking water more than 2,000 years ago
Lauren Del Ciello: I am imagining the moment members of your team started piecing this together. Can you walk me through that?
Dr. Kenneth Tankersley: That is one of the most exciting things about what I do. There comes a point, which I like to call the “Aha moment,” when you are the only one on the planet that knows. You realize you discovered something that no one else knows about. For me, more importantly, it is considering that Native Americans are never looked upon as having any technological sophistication.
Zeolite is this amazing material. Today, rather than mining zeolite, zeolite is produced synthetically. Zeolite has this amazing aspect in that they have microporosity—meaning they can adsorb and absorb. The porosity of zeolite is microscopic and that is why they would filter out dangerous microbes, and even very tiny amounts at the part per million of mercury. This was crucial to the survival of the Maya. And the Maya figured this out 2,000 years ago.
What is amazing to me is that you look to the western hemisphere and some of the things that endanger indigenous people today... It is the same thing. They are facing contamination.
Del Ciello: What is the magnitude of the discovery when compared to other ancient systems globally?
Tankersley: You have to keep in mind where the Maya lived. The Aztecs, for example, or the Inca, other major civilizations in the western hemisphere. Well, they were drinking crystal clear spring water and they had aquaducts and they had water systems that carried the clear spring water to them. The Maya did not have that option.
Being able to recognize a mineral resource and recognize its ability to cleanse water, that is significant. Archeologists have hailed ancient Greece and ancient Romans when someone thought, “Oh, we’ll use a tightly woven bag and we’ll put water in it and the bag will filter out the things that make us sick.” Or, “I know, we’ll use sand and gravel.” The big problem with many other purification systems is they are actually clarification systems rather than purification systems. This is a significant issue. Just because something is crystal clear and transparent, does not mean you can drink it and does not mean it is not toxic.
Del Ciello: It is amazing what you all have been able to deduce by reading the memory of the earth, so to say.
Tankersley: Absolutely. Archeology is the original forensic science. You can think of archeology as the first forensic science and our cases are very cold. We are in now the second decade of the 21st century. Archeology today is not going out and digging up stones, bones and pots; cleaning them up; and putting them on display in a museum. We’ve gone far beyond that. Today, we have to use interdisciplinary techniques to tease out and understand how were people able to survive. You think about at a time today, when so many people are dying of COVID-19, when there are so many people unemployed, when there are people starving to death in the U.S., how in the world can you justify a science such as archeology? I think about that a lot. I think there is a good rationale.
Water is the most precious resource on the planet and it is endangered. The same issues we need to address for our survival, people had to address those thousands of years ago and — like the Maya — they solved them. There are answers in terms of our own adaptability and our own struggle to survive. They can be found in the past. As with zeolite. For indigenous people today living in the U.S. who are facing those organic and inorganic toxicities, such as the Navajo, the Maya system would work. It could easily. It would be interesting if a company would be interested in very simply scaling it down to where it could be used on your tap. Think of the lives that could be saved.
*Responses have been edited for clarity and length. Listen to the full conversation from the Checking In series at bit.ly/checkingin32.