August 26, 2003

New Book Details Civil Engineering Skills Of Ancient Anasazi

‘Water for the Anasazi’ explains how early reservoirs were built in an arid land

download this photo   72dpi .GIF File 300 dpi JPG File       Known for their architectural proficiency, including the spectacular cliff houses of Mesa Verde, the Anasazi were a remarkable group of people. Called the “ancient ones” by the Navajos, they left behind remnants of an advanced civilization, including terraced fields and an ancient road system. They also left behind a mysterious group of rock-ringed, earthen depressions that have long stumped researchers.     An interpretive sign posted by the National Park Service at a site in Mesa Verde National Park, known for decades as Mummy Lake, identified it as either a 1,000-year-old dance platform or an ingenious mesa-top reservoir. The latter theory was given little credence for years due to scientists’ inability to explain how the Anasazi might have engineered a system capable of gathering enough water in that arid land to sustain their society.     Water for the Anasazi: How the Ancients of Mesa Verde Engineered Public Works, by Boulder, Colo., civil engineer Kenneth R. Wright, summarizes his research team’s eight-year study of exactly how the Anasazi mastered such a feat. Edited by Boise State University history professor Todd Shallat, the book is a richly illustrated collaboration between the Public Works Historical Society and the College of Social Sciences and Public Affairs at Boise State, which houses the PWHS editorial offices and publishes the Public Works History newsletter. Water for the Anasazi is No. 22 in an essay series by the PWHS.     Wright uses geologic surveys, pottery shards, carbon dating, ash deposits and pollen samples to determine how four different reservoirs were built and functioned. Used for domestic water and not for irrigation, the reservoirs were relatively shallow (generally between 1.5 and 4 feet in depth). Fed by canals that collected run-off from packed soil, research showed the reservoir bottoms periodically filled with silt and clay, necessitating hand dredging. Over time, the reservoir bottoms rose significantly, forcing adjustment of the inlet canals to ensure that water continued to flow into the basins. One of those raised bottoms created the flat surface erroneously identified as a dance platform so many years later. While scientists are still unsure why the reservoirs were abandoned, a series of horrific droughts was the likely culprit, forcing the Anasazi to abandon the area. Water for the Anasazi is available online through the American Public Works Association at www.apwa.net/bookstore          -30- Water for the Anasazi: How the Ancients of Mesa Verde Engineered Public Works By Kenneth R. Wright, edited by Todd Shallat ISSN 1047-5257, paperback, 81 pages, $15 Public Works Historical Society, 2003 Contact Todd Shallat Department of history 208 426-3701 Media Contact Kathleen Craven communications and marketing 208 426-3275 Return to News home