What surprises lurk in our sewage? How did racist city planners end up saving Black lives? Why does Arizona grow hay for cows in Saudi Arabia? Three strange stories about the most fundamental substance we all take for granted.
 
- SOURCES:- Brian Beach, professor of economics at Vanderbilt University.
- Marc Johnson, professor of molecular microbiology and immunology at the University of Missouri School of Medicine.
- Amy Kirby, program lead for the National Wastewater Surveillance System at the Centers for Disease Control and Prevention.
- Natalie Koch, professor of geography at Syracuse University.
 
- RESOURCES:- Arid Empire: The Entangled Fates of Arizona and Arabia, by Natalie Koch (2023).
- "How a Saudi Firm Tapped a Gusher of Water in Drought-Stricken Arizona," by Isaac Stanley-Becker, Joshua Partlow, and Yvonne Wingett Sanchez (The Washington Post, 2023).
- "Arizona Is in a Race to the Bottom of Its Water Wells, With Saudi Arabia’s Help," by Natalie Koch (The New York Times, 2022).
- "Tracing the Origin of SARS-CoV-2 Omicron-Like Spike Sequences Detected in Wastewater," by Martin Shafer, Devon Gregory, Marc Johnson, et al. (medRxiv, 2022).
- "Water and Waste: A History of Reluctant Policymaking in U.S. Cities," by Brian Beach (Working Paper, 2022).
- Water, Race, and Disease, by Werner Troesken (2004).
- COVID Data Tracker: Wastewater Surveillance, by the Centers for Disease Control and Prevention.
 
- EXTRAS:- "What Is Sportswashing (and Does It Work)?" by Freakonomics Radio (2022).
- "Covid-19," series by Freakonomics Radio (2020-2021).