Angkor, Cambodia, was one of the world’s foremost cities in the 13th century. The ancient urbanization extended across more than 1,000 kilometers and boasted an elaborate water infrastructure network—a system of reservoirs, embankments, and canals that irrigated farmland, diffused floodwaters, and distributed water among residents.
In the 15th century, however, the city collapsed, and its inhabitants moved elsewhere. Experts have long speculated about the reasons for Angkor’s demise. A recent study indicates that the vulnerabilities of the infrastructure network, paired with climatological factors, may have contributed.
A team of experts from the University of Sydney recently used archeological data to create mathematical models of Angkor’s system that allowed them to quantify infrastructure damage caused by variations in climate. Their work is published in Science Advances. The model revealed that damage to infrastructure caused by flooding likely contributed significantly to the city’s ultimate collapse.
Complex networks have proven vulnerable to cascading failure when one issue results in a series of system-wide complications, researchers explain. Their model of Angkor’s intricate network was made up of 1013 edges and 617 nodes. It helped them determine that infrastructure damage was most severe in areas that served as primary hubs, according to Ars Technica, which most likely led to a number of downstream failures.
“The water management infrastructure of Angkor had been developed over centuries, becoming very large, tightly interconnected, and dependent on older and aging components,” co-author Mikhail Prokopenko, director of the Complex Systems Research Group at the University of Sydney, said in a press release. “The change in the middle of the 14th century CE, from prolonged drought to particularly wet years, put too much stress on this complex network, making the water distribution unstable.”
Today’s cities are highly complex and are also connected by aging infrastructure, making them increasingly vulnerable to the effects of extreme weather events and climate change. In fact, the factors contributing to Angkor’s water network failure may parallel challenges faced by modern urban communities struggling with complex critical infrastructure.
What are your impressions? What can we learn about ensuring system resilience from Angkor’s experience?
We’ll explore topics such as water system planning and resilience, stormwater management, water reuse, and groundwater recharge at the Western Water Summit January 22–23, 2019. Join us to be a part of the conversation.