2173 © 2021 The Authors Water Supply | 21.5 | 2021 Historical evolution of urban water conservancy projects in Xi’an, China in the past 3,000 years and its revelations Wei Zhou, Junrui Chai, Zengguang Xu, Yixuan Wang, Kewu Wei and Yungang Dang ABSTRACT Xi’an has a special historical position in ancient China, and it has made great achievements in water Wei Zhou Junrui Chai (corresponding author) conservancy projects in all dynasties. The water network skeleton formed mainly by the ‘Eight Waters’ in Zengguang Xu ’ ‘ Yixuan Wang the territory, along with the historical changes of Xi an, has experienced the Lantian ape-man living by State Key Laboratory of Eco-Hydraulics in the water’, the Western Zhou Fenghao ‘two capitals along the Fenghe River’,andtheQinXianyangcity Northwest Arid Region of China, Xi’an University of Technology, ‘capitalpassedbyWeiheriver’. Developments and changes such as the ‘diversion of water to develop Xi’an 710048, China the capital’ in Chang’an in the Western Han Dynasty, the ‘capital be ringed by eight rivers’ in Chang’an in E-mail: [email protected] ‘ ’ the Sui and Tang Dynasties, reduced water from the end of the Tang Dynasty to the Qing Dynasty, and Wei Zhou the ‘coordinated supply’ after the founding of the People’s Republic of China. After sorting out the Kewu Wei Yungang Dang system,itisbelievedthatthe‘Eight Waters’ in the territory are the original driving force for the flourishing Shanxi Province Institute of Water Resources and Electric Power Investigation and Design, Chang’an in history. From ancient times to the present, with the development of industry, there has Xi’an 710001, China been a trend that human settlements and rivers are farther away. Urban water supply has shifted from groundwater sources to surface water sources. This article investigates the evolution of water conservancy projects in Xi’an from the Paleolithic Age to the present, and studies the relationship between human production and life and water resources. The changing law and development trend of the water supply structure in Xi’an urban area in modern times are analyzed. We have summarized the enlightenment left to us by the practice of water conservancy projects for thousands of years. This paper provides references for the development and planning of water resources in similar cities. Key words | drainage, water diversion, water source engineering, water supply, water transfer HIGHLIGHTS • Water supply methods and water conservancy facilities over thousands of years are summarized. • The variation of water supply in Xi’an urban area in recent decades is investigated. • The development trend of Xi’an’s water supply in the future is analyzed. INTRODUCTION Xi’an, known as ‘Chang’an’ and ‘Haojing’ in ancient times, ancient civilizations, and the starting point of the ancient is the capital of Shaanxi Province, one of the world’s four Silk Road. Xi’an is a historical and cultural city with the richest cultural connotations, the most profound cultural This is an Open Access article distributed under the terms of the Creative heritage, and the most complete preservation of the ancient Commons Attribution Licence (CC BY-NC-ND 4.0), which permits copying city system in the world. It has more than 7,000 years of civi- and redistribution for non-commercial purposes with no derivatives, provided the original work is properly cited (http://creativecommons.org/ lization history, more than 3,100 years of history of the city, licenses/by-nc-nd/4.0/). and more than 1,100 years of history as a capital. Located in doi: 10.2166/ws.2021.043 Downloaded from http://iwaponline.com/ws/article-pdf/21/5/2173/919798/ws021052173.pdf by guest on 27 September 2021 2174 W. Zhou et al. | Historical and revelations of water source project in Xi’an Water Supply | 21.5 | 2021 the middle of the Guanzhong Plain, with Qinling Mountains Bahe River began their cultural creation. According to in the south and Weihe river in the north, the four seasons archaeological research, the Lantian ape-man of Gongwan- are distinct. Since ancient times, Xi’an has been known as gling Mountain reached 1.1 million years ago (Nianhai & ‘Eight Waters Around Chang’an’; ‘Eight Waters’ of Jinghe, Xianzhi ), and this should be one of the earliest active Weihe, Chanhe, Bahe, Juehe, Haohe, Fenghe and Laohe areas of the Chinese nation. In the Stone Age, human rivers. In addition, Zaohe and Xiaohe spatially formed the beings survived only with the products endowed by the natu- water network skeleton in Xi’an. For thousands of years, ral environment. They mainly lived by collecting wild fruits, the ‘eight waters’ have flowed, not only nourishing and nur- hunting and fishing. Constrained by nature and under the turing the people of the ancient city, but also contributing to pressure of survival, humans must live near water to solve Xi’an politics, economy, culture, and society. It has had a water sources, food, and even stones. profound impact in many ways. In the Neolithic period, humans could not dig wells for With the continuous expansion of ‘Greater Xi’an’ city water, so it was impossible to stay away from rivers. The scale and rapid population increase, at the end of 2017, water in the river fluctuates and the living area is closer to the total area was 10,752 km2, the population was 12 the river, so it is more convenient to get water, but if it is million, and the per capita water consumption was too close to the river, it will inevitably be washed away 197.9 m3/person (Shaanxi Provincial Water Resources when the water rises. People in the Neolithic period used Bulletin ), accounting for 82% of the province’s per the second-level terraces near the river as their residence, capita water consumption and for 45% of the country’s which should be a rule of experience gained over a long per capita water consumption, which is a typical resource- period of time. The most numerous Neolithic cultural sites scarce city. So, where is the water source that helped Chan- have been discovered along the Bahe and Chanhe Rivers. g’an flourish in history? What kind of water source changes The sites along the Chanhe River are located on the east did it experience afterwards? What is the enlightenment and west banks, while the Bahe River is limited to the east from the historical evolution of water conservancy projects? bank (see Figure 1 for details). In addition, there are also What enlightenment can we learn? This article aims to Neolithic cultural sites found near the Weihe, Fenghe, and explore these issues and obtain useful enlightenment. Laohe river tributaries of the Weihe River that flow down Due to Xi’an’s geographical location and its special histori- from the Qinling Mountains in downtown Xi’an, as well as cal position as a long-term political, economic, and cultural the pond and lakes along the river (Nianhai & Xianzhi center in ancient China, all dynasties have made great contri- ). Primitive humans ‘living by water’ objectively pro- butions to water conservancy. Combing its achievements, it vided very convenient conditions for frequent contacts and can be derived from the ‘living by water’ of Lantian ape- cultural exchanges among settlements in the river network. man, ‘Two capitals along the Fenghe river’ by Fenghao in Wes- tern Zhou Dynasty, ‘Capital passed by Weihe river’ in Historical evolution of urban water conservancy Xianyang City of Qin Dynasty, ‘Prosperous capital’ of Chan- projects g’an in the Western Han Ddynasty; ‘Capital be ringed by eight rivers’ of Chang’an in Sui and Tang Dynasties, ‘Reduced Xi’an was the ancient capital of 13 dynasties, including the water’ after the abandoned city, and the ‘coordinated supply’ Western Zhou, Qin, Western Han, New Dynasty, Former after the founding of the People’s Republic of China. Zhao, Former Qin, Later Qin, Western Wei, Northern Zhou, Sui Dynasty, Tang Dynasty, Eastern Han Dynasty and Western Jin Dynasty, with a history of 1,140 years. HISTORICAL EVOLUTION The transformation of the ancient capital in the thirteen Lantian ape-man’s ‘living by water’ dynasties is a history of the evolution of water conservancy projects, among which urban water conservancy projects in The primitive humans ‘lived by the water’; as early as the the Western Zhou, Qin, Western Han, Sui and Tang dynas- Paleolithic age, the Lantian ape-men on the terraces of the ties are typical. In addition, the water conservancy projects Downloaded from http://iwaponline.com/ws/article-pdf/21/5/2173/919798/ws021052173.pdf by guest on 27 September 2021 2175 W. Zhou et al. | Historical and revelations of water source project in Xi’an Water Supply | 21.5 | 2021 Figure 1 | Distribution of Yangshao cultural sites in the Chanba two rivers basin (screen from ‘Xi’an Banpo’)(Jun 2000). after the abandonment of the capital are in the same line as Xiqi. King Wen and King Wu established Fengjing and the destiny of the city, and appear weak and unsustainable. Haojing on the west and east banks of the Fenghe River respectively, establishing the Western Zhou Dynasty. Since ‘Two capitals along the Fenghe River’ by Fenghao in then, Xi’an began its historical structure as the political, Western Zhou Dynasty economic and cultural center of ancient China, and began its glorious history of building the capital of thirteen emper- In the 11th century BC, people from the Zhou Dynasty ors (Si ). entered the Fenghe River basin on the south bank of the Fengjing and Haojing in the Western Zhou Dynasty Weihe River in the central part of the Guanzhong from were the earliest twin cities in the world.