Forget your fancy faucet. An ancient water feature found in the Maya city of Palenque, Mexico, is the earliest known example of engineered water pressure in the New World.
The area of Palenque, in Chiapas, was first occupied about the year 100 but grew to its largest during the Classic Maya period between 250 and 600. Underground water features are not unusual there. Because the city was built in a constricted area in a break in an escarpment, the Maya routed streams beneath plazas via aqueducts to make more land available for living.
"They were creating urban space," says Kirk French, lecturer in anthropology at Penn State, and also at least partially controlling flooding from the approximately 10 feet of rain that falls during the six-month rainy season.
French first identified the Piedras Bolas Aqueduct, a spring-fed conduit located on steep terrain, in 1999 during a mapping survey of Palenque. In 2006, he returned with Christopher Duffy, professor of civil and environmental engineering, to examine the feature.
The elevation drops about 20 feet from the entrance of the tunnel to its outlet about 200 feet downhill, the researchers report. In cross section, the width of the conduit decreases from 10 square feet near the feeding spring to a half square foot where the water emerges. The combination of gravity and sudden constriction would have caused the water to flow out of the opening under pressure enough, Duffy estimates, to shoot upwards to a height of 20 feet—enough to power a fountain, or to lift water up to the adjacent residential area for use as wastewater disposal.
"Water pressure systems were previously thought to have entered the New World with the arrival of the Spanish," the researchers wrote in a recent issue of the Journal of Archaeological Science. Yet the Piedras Bolas Aqueduct shows that the Maya "had empirical knowledge of closed channel water pressure predating the arrival of Europeans."
Christopher Duffy, Ph.D., is professor of civil and environmental engineering in the College of Engineering, cxg11@psu.edu. Kirk French, Ph.D., is lecturer in anthropology in the College of the Liberal Arts, kirkdfrench@psu.edu. The National Science Foundation and the Foundation for the Advancement of Mesoamerican Studies, Inc., supported this work.