Irrigation
In order to increase the amount of farmland surrounding the city, a vast network of canals that diverted water from the Moche river into the area around the city was installed. It was only with the construction of these canals that the city's population could increase. Before the canals were dug, the city relied on a number of wells that were dug up to 15 meters into the ground. Many of the canals to the north of the city were destroyed by a catastrophic flood in c. 1100 AD, which was likely the key motivation for a need for the Chimú to refocus their economy towards one rooted in foreign resources rather than subsistence farming. Chan Chan is home to water reserves called huachaques.
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