How did the Aztecs Prevent Flooding in Tenochtitlan?

How did the Aztecs Prevent Flooding in Tenochtitlan?

The Aztecs built dikes, canals, and causeways to defend their capital city of Tenochtitlan from seasonal flooding. Two 2.5-mile-long aqueducts were going in to the city that provided fresh water to the residents. A ten-mile dike was erected by the Aztecs to close off a section of the lake. It kept the water clean and kept the city safe from flooding. 

Even though the Aztecs were described as savage and uncivilized by the early Spanish conquistadors, they were quite advanced. They had a complicated legal system, as well as social stratification and intricate art. Their engineering abilities were also impressive, as they solved their agricultural issues by building raised beds amid the lake that surrounded their island house.

How Did The Aztecs Obtain Clean Water For Tenochtitlan?

The Aztecs used the aqueduct built by Nezahualcoyotl between 1466 and 1478 to bring potable water to Tenochtitlán from springs on the continent. When the first aqueduct proved insufficient, the monarch Ahuizotl built a second aqueduct in the years 1499–1500.

The excrement was utilized as fertilizer on chinampas (floating pieces of land) or sold for use in tanning animal skins on the market. Urine was collected in ceramic jars and used as a mordant for coloring fabric later on. 

The atmosphere of Tenochtitlán was healthy for its period, especially when compared to European cities. Public and personal cleanliness helped to reduce the number of diseases and their severity.

A reliable source of safe drinking water is vital, and the Aztecs were ahead of their time in this regard. While London received its drinking water from the filthy Thames River until 1854, Aztecs had figured out how bring clean water into their cities centuries before.

Where Did Aztecs Get Their Water From?

The Aztecs’ major supply of fresh water at Tenochtitlan was the Chapultepec aqueduct. The Aztecs depended heavily on aqueducts to carry spring water into the city from neighboring hills. This was the purest and most recent.

The Chapultepec aqueduct (acueducto de Chapultepec in Spanish) was built to bring drinkable water to Tenochtitlan, now Mexico City. During the 15th century, the Aztecs built two aqueducts that followed the same course from the springs, the first of which was destroyed by floods and the second by the Spanish.

Lake Texcoco is a spring-fed lake that is both huge and shallow, as it is not supplied by large running rivers. They discovered out that they could float on the water by constructing little rectangle-shaped regions out of reeds and grasses. They could then scrape soil from the shallow lake bed and place it on the floating vegetable plots.

It was a hit with the crops. The fertile lakebed soil, scorching sun, and water from the lake wicking up through the bottom of the beds to irrigate the plants were all very fertile, as you might guess. That was the case. Instead of only one crop, they were able to turn 6-7 crops in a year. This greatly enhanced their food output, allowing them to feed a bigger population and conquer thousands of square kilometers of territory to establish an Empire.

Why Was Tenochtitlan Built On A Lake?

The Aztecs built their city Tenochtitlan on water (specifically on a lake that later became an island) to grow crops and stay protected from outsider enemies. 

The Aztecs built their city based on a mythological belief. According to legend, once the Mexicans departed Azlan, the God Huitzilopochtli gave them specific directions on where they should establish their altepetl (city-state). The instructions were to go locate a location where an Eagle will be perched atop a nopal cactus on an island in the midst of a lake. The Mexican tribe traveled for thousands of years until arriving at the Texcoco Lake, where the prophecy was achieved in 1325.

The Aztecs utilized the floating island to grow their main crop, maize, once it was safe and usable. They also grew a variety of vegetables (avocados, beans, chili peppers, squash, and tomatoes), as well as flowers on occasion. Unfortunately, the Aztecs did not have any animals or machinery to assist them in their job.

Ahuitzotl, the Aztec emperor, tried to construct an aqueduct that would transport fresh water from the mainland to the lakes around Tenochtitlan. In 1502, the aqueduct broke, causing a severe flood in the city.

Did The Aztecs Invent Aqueducts?

No, the Aztecs were not the first to invent aqueducts. In 312 BC, the city of Rome (Italy) received its first Roman aqueduct, the Aqua Appia. Although aqueducts were not invented by the Romans, they were excellent engineers who advanced the design and construction of aqueducts to new heights.

The word aqueduct is derived from the Latin word aqueducts, which is derived from the roots aqua, which means water, and ducere, which means “to lead.” Because of the root word aqua, some people mistakenly spell aqueduct with an A instead of an E, but you’ll know better now.

The Aztecs are famous for their extensive network of aqueducts that provided water for cultivation and bathing.

The waterways were built through the use of slave labor. Slavery was a huge part of the Aztec society and did not cease to be used as labor in the construction of the aqueducts. Slaves worked full days to complete these massive structures and often died on the job.


The Aztec peoples formed a civilized nation that provided clean water resources which made the Aztec civilization ahead of its time. Although the capital Aztec city tragically came to an end, it had rather interesting and vital importance in the building and flourishing of the city. Because no one else desired the area, the Aztecs were allowed to settle there.

It wasn’t the best site to establish a city at first, but the Aztecs quickly created islands where they could produce food. And they succeeded in doing so! They grew a variety of plants such as maize and avocados which flourished the Aztec cuisine later on.