From ancient wisdom flows modern water solutions

Highly sophisticated water management techniques of ancient civilisations demonstrate the ingenuity of inhabitants who lived with limited water. It appears we need to look to the past to ensure a stable water supply in the future.

Even in today’s information age, there is much to learn from ancient civilisations, particularly when it comes to an essential resource such as water. For example, a recent study revealed how more than three centuries ago, Great Zimbabwe – the largest city in southern Africa during the Middle Ages – stored water in dhaka pits to overcome severe water scarcity and drought.

Professor Innocent Pikirayi of the Department of Anthropology, Archaeology and Development Studies at the University of Pretoria (UP) was part of the research team that discovered how the community of Great Zimbabwe maintained a stable water supply in a region known for periodic droughts and which is presently water-scarce.

The study was conducted in the context of growing water security challenges, currently among the most significant global challenges for human subsistence and environmental health. It highlights the importance of effective strategies for water management and conservation today.

“Our research – conducted with academics from Great Zimbabwe University, the University of Cambridge in the UK and Aarhus University in Denmark – has identified dhaka pits, which were part of the ancient city’s water infrastructure,” Prof Pikirayi says.

These infrastructures were originally interpreted as remnants of excavations of clay (dhaka) used to construct residences.

“However, recent archaeological surveys and excavations, geo-archaeological sampling, and remote sensing techniques like LiDAR (light detection and ranging) revealed that these depressions were part of a very complex, ‘climate-smart’ water management system,” he adds.

Throughout history, human civilisations have engineered extraordinary water management systems that enabled urban growth, agricultural productivity and cultural flourishing.  

“Among the Chinese, Armenians, Persians, Mesopotamians, Egyptians, Romans, Greeks, Aztecs, Incas, Harappans and other societies, there is evidence of sophisticated ancient water infrastructures that present valuable insights for addressing contemporary water disasters, water shortages, water quality and climate change,” says Dr Meisie Rasakanya, an expert on modern water infrastructures. “As such, the civilisations associated with these societies survived for a long time.”

Ancient societies had a thorough understanding of local hydrology and the need for the sustainable management of water. They were also able to accurately read changes to the environment and climate, and respond with long-term solutions to retain or conserve water sources and resources.

“This demonstrates resilience in the face of acute diversity, particularly during the Little Ice Age,” Dr Rasakanya says. “The damming of water in a hilly place such as Great Zimbabwe is indicative of the ability by the ancients to minimise water losses, managing to retain it where sloping and gravity would have encouraged rapid water flows downstream.”

The preservation of the dhaka pits in Great Zimbabwe is evidence of the durability of their construction – an engineering attribute required of all modern water infrastructures, given the challenges of variable rainfall patterns, most of which result in flooding.

“Lessons from Great Zimbabwe as well as other ancient civilisations that need to be put into practice include adopting water management as an integrated system and implementing a holistic approach, from harvesting to storage, distribution and discharge, rather than managing the resource in a fragmented and uncoordinated manner,” Prof Pikirayi says. “Key to this integrated approach is involving communities, because they are integral to the development and sustenance of civilisations.”

Why this research matters

Ancient water management systems offer valuable lessons for addressing contemporary water scarcity challenges in sub-Saharan Africa, particularly in urban areas that are facing similar environmental pressures. Using some of these lessons from the past, we can develop and implement more resilient, sustainable and equitable water management solutions for a world confronted with water scarcity and, in some cases, flooding.

Water-wise lessons from ancient societies

• Ancient Romans and Persians conveyed water to distant places by way of gravity-fed systems such as aqueducts and qanats. 

• The Chimú Indians of Peru harvested nutrient-rich sediments from seasonal floods to fertilise farms and enhance the agricultural potential of soils.

• In Mesopotamia and other parts of Asia, ancient societies addressed water shortages and excesses by constructing canals and reservoirs.

• In sub-Saharan Africa, evidence of furrow construction and terracing shows how ancient societies relayed water and conserved moisture in regions that would be regarded as marginal for agriculture today.

• In Great Zimbabwe, the damming of water was critical in sustaining the ancient city for more than two centuries. This was in response to the onset of adverse climate events.

This story first appeared in RE.SEARCH Issue 12: Global.

Researchers

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  Professor Innocent Pikirayi

  Professor Innocent Pikirayi joined the University of Pretoria (UP) in 2004. He is Deputy Dean of the Faculty of Humanities, where he is responsible for postgraduate education and research. He is a graduate of the University of Zimbabwe.  

  In terms of how his field of research, African archaeology, contributes to the betterment of the world, Prof Pikirayi says: “Archaeology examines cultural and human-induced environmental changes over time, determining trends and patterns, and seeks to make sense of these. It offers a unique perspective on human history and culture, and helps us to understand not only where and when people lived on this planet, but also how they have shaped it and continue to modify it. Such information is important in understanding the current human condition.”

  His research is cross-disciplinary. Prof Pikirayi works with researchers such as Prof Søren Kristiansen of the Department of Geoscience at Aarhus University, Denmark, and Dr Federica Sulas, a geo-archaeologist at Cambridge University’s McDonald Institute for Archaeological Research in the UK.

  Prof Pikirayi is part of an international team of scholars from Africa, Europe and the US that is studying ancient complex societies in sub-Saharan Africa, focusing on the Great Zimbabwe civilisation. The team makes use of approaches in historical ecology, geoarchaeology and conventional archaeology. The collaborative research on Great Zimbabwe goes back to 2015/2016, and focuses on the role of water in socio-political formation. Highlights of this research involve the remapping of ancient and present-day water features on the site using light detection and ranging (LiDAR) mapping, which revealed how the ancient community managed and conserved water resources.

  As far as role models go, Prof Pikirayi points to Peter Storr Garlake (1934 – 2011), an architect, archaeologist and author of the book Great Zimbabwe (Thames and Hudson, 1973). Garlake taught him at undergraduate level and inspired his early career in archaeology. Prof Pikirayi has written a tribute to Garlake.

  As for his early career as a scholar, Prof Pikirayi credits his doctoral supervisor Prof Paul JJ Sinclair as being highly influential, especially his doctoral thesis, ‘Space, time, and social formation: A territorial approach to the archaeology and anthropology of Zimbabwe and Mozambique c 0 – 1700 AD’ (Uppsala University, 1987). He also owes his growth as a senior scholar in archaeology to the numerous interactions and collaborations he has had with Prof Peter Ridgway Schmidt of the University of Florida, who encouraged him to employ locally grounded theories in understanding the African past.

  Prof Pikirayi hopes to become a leading scholar in African archaeology, and use archaeology as an avenue towards other frontiers of knowledge (such as volcanology, plate tectonics, and water and soil sediments) about the origins of Earth.

  “Archaeology is about the human experience and condition over time, so it is important to understand past lifeways and how these have developed to the present day. That is why my research matters,” he says.

  “Such past experiences are also important to us in terms of our broader social and cultural context and how we have shaped the world in the form that we see it, live in it and experience it,” he adds. “Some of the lessons we learn from deep history, which archaeology is part of, hold fundamental clues towards understanding the modern human crisis, such as water scarcity, environment and climate change. Archaeology is the surest way of confirming that humans are changing Earth’s environment at an unprecedented timescale. The very same humans need to put mechanisms in place to halt this. My work at Great Zimbabwe speaks to these broader realities.”

  His advice to school learners or undergraduates who are interested in his field is to realise that archaeology is not primarily about the past but about how the past speaks to the present.

  “Once you understand this, learning archaeological theory and methods become extremely easy. In fact, practising archaeology in the field and in the laboratory becomes a passion.”

  His hobbies include landscape gardening, hiking and mountain climbing. In December 2020, during the pandemic, he scaled Mount Kilimanjaro to Uhuru Peak, the highest summit in Africa.

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