Prehispanic water pressure: A New World first Kirk D. French a, * , Christopher J. Duffy b a Department of Anthropology, The Pennsylvania State University, 409 Carpenter Building, University Park, PA 16802, USA b Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA 16802, USA article info Article history: Received 26 March 2009 Received in revised form 30 November 2009 Accepted 4 December 2009 Keywords: Maya Water pressure Water management Urbanism Hydrology abstract Ancient cultures have a wide range of water control management techniques, each associated with a particular purpose, including water for consumption, agriculture, flood control, drought relief, and rituals (Scarborough, 2003). One technique that has received limited archaeological attention is the purposeful creation of water pressure to perform useful work. Perhaps the earliest such example was found on the island of Crete in a Minoan palace and dates as early as 1400 BC. Terracotta pipe segments with graded diameter reductions were used to create fountains (Evans, 1921–1935). Although gravity and the weight of water are the most efficient means of generating water pressure in a closed conduit, natural conditions (climate, geology, topographic slope, etc.) that might lead to the construction of water pressure systems are less clear. Here we show that the Classic Maya (AD 250–600) constructed a water pressure system with the potential to control the flow of water within an urban area. By burying a conduit along a steep ephemeral channel passing through a residential group, upland springs could be diverted to build pressure in the conduit to provide a dry-season supply of water. Up to 6 m of hydraulic head could have been recovered to lift water from the pressurized conduit to a point of use. Water pressure systems were previously thought to have entered the New World with the arrival of the Spanish. Yet, archaeological data, seasonal climate conditions, geomorphic setting, and simple hydraulic theory clearly show that the Maya of Palenque in Chiapas, Mexico had empirical knowledge of closed channel water pressure predating the arrival of Europeans. Ó 2009 Elsevier Ltd. All rights reserved. 1. Introduction The ancient Maya are renowned as great builders, but are rarely regarded as great engineers. Their constructions, though often big and impressive, are generally considered unsophisticated in terms of engineering techniques and knowledge, as we understand them today. Most large Maya constructions required only a simple grasp of building techniques as well as a good supply of unskilled laborers. One major exception to this widely held view relates to water control and manipulation. Many Maya centers exhibit sophisticated facilities that captured, routed, stored, or otherwise manipulated water for various purposes. Palenque, one of the best known Classic Maya centers, has what is arguably the most unique and intricate system of water management known anywhere in the Maya Lowlands. Years of archaeological research, including intensive mapping between 1997 and 2000, reveal that this major center, situated on a narrow escarpment at the northern boundaryof the Chiapas Plateau. The site began as a modest settlement about AD 100. Then, during the seventh and eighth centuries, Palenque experienced explosive growth, mushrooming into a dense community with an estimated population of 6000 and approximately 1500 structures d residences, palaces, and temples d under a series of powerful rulers (Barnhart, 2001). The first official acknowledgment of the ruins at Palenque appears in a letter written by Ramo ´ n Ordon ˜ez y Aguiar to the president of the Real Audiencia of Guatemala in 1773 (Gonza ´ les, 1986). Historical research sheds light on a much earlier discovery by Fray Pedro Lorenzo de la Nada (ibid.). In 1560, Fray Domingo de Azcona invited Fray Pedro to work with the Indians in and around the colonial city of San Cristo ´ bal de las Casas. For 6 years Fray Pedro worked closely with the Chol and Tzeltal Indians before visiting the Palenque area. During that time, he became fluent in their native languages. When he reached the lowlands, he assisted the Indians by setting up a new town near the Chacamax River, 8 km southeast of the ruins. Fray Pedro named this new town Palenque, meaning, according to Spanish dictionaries, ‘‘palisade or stockade of wood.’’ Miguel Angel Ferna ´ ndez, Palenque’s head archaeologist during the 1930s, comments in his field reports that ‘‘the natives of the area referred to Palenque [ruins] by the name of Otolum’’ (Gonza ´les, 1986: 5). This name is a word of Chol origin, derived from: otot (house); tul (strong); lum (land), together meaning ‘‘strong house land’’ or ‘‘fortified place’’ (Gonza ´les, 1986; Becerra, * Corresponding author. Tel.: þ1 814 865 1142. E-mail address: kirkdfrench@psu.edu (K.D. French). Contents lists available at ScienceDirect Journal of Archaeological Science journal homepage: http://www.elsevier.com/locate/jas 0305-4403/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.jas.2009.12.003 Journal of Archaeological Science 37 (2010) 1027–1032