A civil engineer studying the use of water by ancients said paleohydrology has shaped the study and research of the Machu Picchu site in South America when he spoke Tuesday night at the University of Tennessee.

Kenneth Wright, civil engineer and founder of Wright Water Engineers and the Wright Paleohydrological Institute, explained paleohydrology is "the study of water use and water handling by ancient people."

Wright said the environment and geography of the site make it a prime candidate to study paleohydrology.

What makes it remarkable is that they did all this without the wheel, without a written language, without iron or steel.
Kenneth Wright

"One of the important things about Machu Picchu is the river that circles it," Wright said. "And that is the Vilcanota River that surrounds Machu Picchu on three sides. Machu Picchu is great for studying hydrology because it gets lots of rain - even more than this city, in Tennessee. It's 80 inches a year, while here you may only get 55."

Through new technology and extensive research, Wright and his colleagues determined that rainfall accumulation had increased during the time the Incas inhabited Machu Picchu from 1450 to 1540. The rainfall and natural springs allowed the Incas to build canals, aqueducts and fountains to provide water to the city's inhabitants.

The Incas who occupied Machu Picchu were not only "masters of sub-surface drainage" and water engineering, but also architecture and slope stabilization, Wright said. "What makes it remarkable is that they did all this without the wheel, without a written language, without iron or steel," he said.

Wright's speech was organized by the East Tennessee Society of the Archaeological Institute of America.