Cities across time have stretched to secure water. The Romans built aqueducts, the Mayans constructed underground storage chambers, and Hohokam farmers dug more than 500 miles of canals in what is now the U.S. Southwest.
Today’s cities use portfolios of technologies to conserve supply — everything from 60-story dams and chemicals to centrifugal pumps and special toilets. And yet, the cities of tomorrow will have to do more.
A recent United Nations report on drought says climate change is increasing the frequency, severity and duration of droughts, which contribute to food insecurity, poverty and inequality. The report also asserts that “drought has been the single longest-term physical trigger of political change in 5,000 years of recorded human history.” It calls for urgent action and a transformation in governance to manage modern drought risk more effectively.