Puquios

The Puquios are an old system of subterranean aqueducts near the city of Nazca, Peru. Out of 36 Puquios, most are still functioning and relied upon to bring fresh water into the arid desert. The Puquios have never been fully mapped, nor have any been excavated.

There is conflicting research regarding when the aqueducts were actually built. Some archaeologists contend that they were built by Pre-Columbian Nazca architects around A.D. 540 in response to two prolonged droughts during that time, others doubt that. There is a general lack of historical reference both after and prior to the Spanish Empire. The first historical writing of their existence was in 1605 by Reginaldo de Lizárraga, which some contend may indicate that they were built by the Spanish. There, however, is yet no evidence from Spanish texts that mentions a project to build the Puquios, nor is there evidence in early Spanish texts of water systems being already in place when they conquered the territory.

In their book Irrigation and Society in the Peruvian Desert, Katharina Schreiber and Josue Lancho Rojas explore puquios and show evidence that puquios were constructed by a pre-Hispanic civilization. Monica Barnes and David Fleming on the other hand, argue that Schreiber et al misinterpreted evidence and that there are easier explanations for a construction in colonial times. Some investigations have been performed to determine the age of puquios also by using radiocarbon dating of organic materials (Bonn-1972) and accelerator mass spectrometer to date rock varnishes (Clarkson and Dorn 1995). With this technique some puquios were dated to around the 6th and 7th century AD.

Rosa Lasaponara, Nicola Masini and their team of the Italian CNR (National Research Council), in cooperation with the archaeologist Giuseppe Orefici, studied the puquios using satellite imaging. They found clear evidence that the puquio system must previously have been much more developed than it appears today. A series of canals was used to bring to the surface water from underground aquifers and channel it to the areas where it was needed. Any excess was stored in surface reservoirs. To help keep the water flowing chimneys were excavated above the canals in the shape of corkscrewing funnels. These funnels admitted wind into the canals, and the difference in atmospheric pressure along the canal length forced the water through the system and eventually to the desired destination. By means of satellite imagery it was also possible to discover unknown puquios in the Nasca drainage basin;

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