Historical Kurit Dam in Tabas: Analysis of the Construction Technology

Studying historical dams and embankments, determining their construction date, and investigating the type of technology and creativity used in their design are of particular importance, yet few studies have addressed these so far. The historical Kurit Dam is located at the edge of the Central Desert of Iran, about 56 km away from Tabas in the province of South Khorasan. This study uses field and library research methods and laboratory experiments. The exact dimensions and drawings of the current situation of the dam structure were surveyed for the first time, and the lifespan and different phases of construction were determined by taking samples from different parts of the dam body. Moreover, the technology used to construct this structure was investigated. The results reveal that this masonry arch dam which was constructed without a diversion tunnel in the river serves as a historical record in terms of technology, phased construction, and installation of all necessary elements of a dam. Results of thermoluminescence dating show this dam is more than 700 years old and is constructed in several phases at different time intervals. After the end of the useful life of the dam when the reservoir was filled with sediments, the dam height was increased and its final height from the riverbed reaches 54.4 m. The first part of the dam body with the height of 16.8 m from the riverbed was constructed in 685 AS. The second, third, and fourth parts, with the intervals of about 50, 350, and 100 years from the previous stage, increased the height of the initial structure by 19.2, 9, and 9.4 m, respectively. This dam was constructed of irregular and regular stone material as well as bricks and was employed by the locals for about seven centuries.