Water Filtration in the New World
The Maya city of Tikal had an effective water filtration system.
Between about 165 BCE and 1055 CE their main water reservoir used a
mixture of the mineral zeolite and coarse, sand-sized crystalline quartz.
The Maya people in Central America built elaborate systems of
water management during the Late Preclassic to Late Classic cultural period.
The Maya rulers linked themselves with the provision of water
for their people.
Their water system surpassed what the Spanish invaders of the 1500s
had back at home.
Europeans figured out how to filter water with zeolite in the early
twentieth century.
And they assumed, of course, that they must have been the very first to do so.
Zeolite Filtration
The Minoan civilization on Crete used slaked lime and finely ground potsherds
to form a waterproof lining for baths, cisterns, and aqueducts.
The Greeks used volcanic ashes and tuffs in this way at least as early
as 500–400 BCE on Rhodes.
That practice spread east to the Romans, who used volcanic pumice.
With the decline of the Roman empire, much of the practical knowledge
on this technology was lost.
It began to be rediscovered in the 16th century.
Zeolites, however, weren't used for water purification in Europe until
the early 20th century.
Zeolites are a class of microporous minerals.
They're aluminosilicates, based on AlO45–
and SiO44–
tetrahedrons, which are joined into a framework with regularly
spaced and sized pores of molecular dimensions.
This makes them molecular sieves, as they sort molecules by size,
the maximum size that can enter their pores.
They're also adsorbants, able to extract ions or molecules
from a liquid.
Zeolites form naturally where volcanic rocks and ash layers
react with alkaline groundwater.
Now they're produced in large-scale industrial processes,
to be used commercially as adsorbents and catalysts.
The largest single use of zeolite is in laundry detergent.
Non-clumping cat litter is another common household use of zeolites.
Tikal
Tikal, likely called Yax Mutal
or Yax Mutul
by its inhabitants, was the capital city of one of the most powerful
kingdoms of the ancient Maya civilization.
It's in the rainforest in the Petén Basin of today's Guatemala.
Tikal dominated the Maya region economically, politically, and militarily.
Plate 1: View from Temple I, Looking West, showing Temples II, III, and IV.
Teotihuacan in the Valley of Mexico.
Visiting
Teotihuacan
Tikal interacted with cities throughout Mesoamerica, as far north as
Teotihuacan
in the Valley of Mexico.
The city of Tikal covered more than 16 square kilometers,
and had about 3,000 structures.
Population estimates vary from 10,000 to as high as 90,000 in the city,
with totals of about 120,000 and 425,000 within radii of 12 and 25
kilometers, respectively.
Tikal had no water supply other than the rainwater they collected
in ten reservoirs.
The city now gets an average of 1,945 millimeters of rainfall each year.
However, rain arrived irregularly, with long periods of drought.
There are signs of early agriculture at Tikal's site dating back to 1000 BCE.
Large-scale construction including major pyramids and platforms
began around 400–300 BCE
In the first century CE its large northern competitors began to decline,
and Tikal flourished.
By 200 CE Teotihuacan had embassies in Tikal.
View from Pyramid of the Moon in Teotihuacan looking out over the
Plaza of the Moon and the many smaller ritualistic structures,
down the Avenue of the Dead and past the Pyramid of the Sun
toward the Temple of Quetzalcoatl.
On 14 January 378 CE the fourteenth king of Tikal,
Chak Tok Ich'aak or Great Jaguar Paw, was killed.
That same day, Siyah K'ak' or Fire is Born
arrived from the west.
It's thought that Siyah K'ak' was a foreign general serving a figure
represented as Spearthrower Owl,
an image well known in Teotihuacan, likely representing its ruler.
It seems that Siyah K'ak' led an invasion of forces from Teotihuacan,
defeating, capturing, and immediately executing the native king
Chak Tok Ich'aak, with the aid of a powerful faction living at Tikal.
Yax Nuun Ayiin I or First Crocodile, the young son of Spearthrower Owl,
was installed as the fifteenth king of Tikal within a year.
He reigned for 47 years, under the control of Siyah K'ak'
as long as that general lived.
First Crocodile took a wife from the defeated Tikal dynasty,
and his son Siyaj Chan K'awiil II succeeded him.
However, these foreign rulers soon were Mayanized.
In the 400s Tikal's rulers built large systems of ditches and earthworks
along the northern and southern perimeters, joined up to the
natural defenses of swamps to the west and east.
The ditches and earthworks were thought to be purely defensive,
protecting the area of about 120 square kilometers.
Research since 2004 has shown that it was a water collection system.
Plate 6: Temple V, Looking Southeast.
Tikal's Water Filters
Zeolite water purification at Tikal,
an ancient Maya city in Guatemala
A 2020
paper in Nature
described recent research into the water purification system at Tikal.
The native people in North America could get water from naturally
filtered springs.
They could also boil water, and store water in earthenware pottery
that pulled contaminants to the vessel sides.
The Aztec people in today's Mexico brought water from artesian springs
to their cities through aqueducts.
The Inca people in South America also built aqueducts to carry
water from springs in the Andes mountain to their cities.
The Maya cities were built on a limestone karst landscape,
set in a tropical monsoon climate.
The people needed to collect water in reservoirs,
and that water needed filtration.
Buildings at Tikal were painted in bright colors,
including vermillion and red created with pigments based on cinnabar.
That's a form of mercury sulfide or HgS.
Mercury leached out of the paint and contaminated the water reservoirs.
Plate 8: Palace of Five Stories: North Side of Third, Fourth, and Fifth Stories.
Cyanobacteria and blue-green algae were present throughout the region,
and they also contaminated the reservoirs.
Some varieties produced toxins.
The Corriental reservoir was one of the largest at Tikal,
holding about 58 million liters.
It was the only one with a filter system.
The channel bringing water to the reservoir ended with a dry-laid
limestone wall that allowed water to flow through it.
They placed a layer of woven petate, reed or palm fiber matting,
on the upstream side of that porous limestone wall.
Then they added a mixture of zeolite minerals and
quartz crystals about 0.5–2.0 mm in size,
and another petate woven layer on the upstream side of that.
The zeolite — analcime, clinoptilolite, and mordenite —
was carried in from deposits about thirty kilometers to the northeast,
where it had been derived from volcanic tuff.
There are active, dormant, and extinct volcanoes in the region.
The zeolite's adsorbant characteristics let it filter harmful microbes,
nitrogen compounds, and inorganic and organic toxins out of the water.
The Corriental reservoir, with its zeolite filter,
was not contaminated by mercury or blue-green algae.
It was not only the only such one at Tikal,
but the only one in the Maya Lowlands.
Plate 10:
1: The Middle North Chamber of the first story of
the Palace of Two Stories.
2: The Rear Gallery of the fourth story of the Palace of Five Stories,
looking east.
The Corriental zeolite water purification system protected the
residents of Tikal for 1,000 years.
Tikal's water purification engineers built it about 600 years before
the South Asian sand and gravel water filtration described in the
Suśrutasaṃhitā,
often cited as the first water filtration system.
There are thousands of ancient Maya water reservoirs,
but less than fifty have been carefully investigated.
Who knows how many other filtration systems are out there?
The End of Tikal
By the 600s Teotihuacan had no active presence in any Maya city,
and by 700 the center of Teotihuacan had been demolished.
By the 800s the Classic Maya civilization was collapsing across the region.
However, there was still some construction at Tikal.
Temple III, shown below, was the last of the city's major pyramids.
It and some smaller monuments were built to mark the
beginning of the 19th K'atun in 810 CE.
Plate 4: Temple III, Looking Northwest.
June 22, 810, was 9.18.19.17.19,
b'ak'tun 9,
k'atun 18,
tun 19,
unial 17,
k'in 19.
June 23 was 9.19.0.0.0.
The Mayan word for "day" is k'in.
20 k'ins make an unial or winal.
18 unials (or 360 days) make a tun.
20 tuns (or 7,200 days, about 19.71 years) make a k'atun.
20 k'atuns (or 144,000 days, about 394.25 years) make a
b'ak'tun.
The system continues with factors of 20 through piktun,
kalabtun, k'inchiltun, and alautun.
One alautun is 23,040,000,000 days, a little over 63 million years.
The zeolite filter system needed to be rebuilt after a flash flood.
The upper layers of sediment in the Corriental reservoir showed that
the filtration system had been destroyed around 1055 CE and not rebuilt.
Mercury from the cinnabar paint began contaminating the water.
So did the blue-green algae.
It was a time of drought, and the only available water
was covered with the slime of blue-green algae.
Plate 11:
1: Palace of Two Stories and Twenty-One Chambers: Southern Chamber of
Rear Row of Chambers, First Story.
2: Interior of Middle Palace Formerly of One Apartment and Later Divided
into Three Rooms.
In the end, with their water sources so badly contaminated, the residents
of Tikal had no choice but to leave their once-thriving city.
Central authority collapsed, and most of the population left Tikal and
its surroundings betweeen 830 and 950.
The local people knew about the ruins all along, although the Spanish
conquistadors apparently knew nothing about it.
In the 1840s and 1850s the local people guided some explorers
to the ruins of Tikal.
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Confederate Shrine Almost Repurposed As A Toilet
