When the Spanish arrived on the desert north coast of Peru shortly after 1532, early chroniclers remarked on the verdant, green valleys across the region.
The Spanish immediately recognized the importance of the canal network. They had used similar canal technology in Spain for centuries. So, they set about conscripting Indigenous labor and adapting the irrigation system to their goals.
Just a few decades later, however, historic records describe sand dunes and scrublands invading the green valleys, water shortages, and in 1578, a massive El Niño flood that nearly ended the young colony.
So how did the Indigenous operation of this landscape succeed, where the Spanish and the modern-day agro-industrial complex have repeatedly failed?
CULTURal knowledge WAS CRUCIAL FOR ANCIENT CANAL SYSTEMS
Ancient beliefs, behaviors, and norms—what archaeologists call culture—were fundamentally integrated into technological solutions in this part of Peru in ancient times. Isolating and removing the tools from that knowledge made them less effective.
Scientists, policymakers, and stakeholders searching for models of sustainable agriculture and climate adaptations can look to the archaeological record. Successfully applying past practices to today’s challenges requires learning about the cultures that put those tools to work effectively for so long.
The pre-Hispanic societies of Peru developed agricultural principles around the realities of the desert, which included both dry seasons and flash floods.
Large-scale irrigation infrastructure was combined with low-cost, easily modified canals. Aqueducts doubled as sediment traps to capture nutrients. Canal branches channeled both river water and floodwater. Even check-dams—small dams used to control high-energy floods—worked in multiple ways. Usually made of mounded cobble and gravel, they reduced the energy of flash floods, captured rich sediments, and recharged the water table.
