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Urban Water Chemistry with Stephen MacAvoy and Melissa Pierce

·26 min·1 clip

Steve McAvoy says siloxanes are synthetic compounds nature does not make.

1. The Show About Science episode “Urban Water Chemistry with Stephen MacAvoy and Melissa Pierce” moves between the Chicago River and Washington, D.C. to track urban water chemistry. 2. Nate hosts Melissa Pierce, the Technical Program Director at Current, and Steve McAvoy, a professor at American University, because they explain river monitoring from two cities. 3. The episode asks what it means to test a river, why water quality cannot be judged by sight, and how cities track risks in recreational water. 4. Melissa Pierce says Current is a Chicago-based nonprofit water innovation hub and that its H2Now program launched in 2021. 5. She describes fecal coliform bacteria as indicator organisms found in humans and warm-blooded animals that can signal other pathogens from waste. 6. She says H2Now gives the public real-time microbial water monitoring for the Chicago River during the recreational season. 7. Melissa shifts to Chicago’s 1800s history, when human waste, industrial waste, animal carcasses, and trash were dumped into the river. 8. She explains that the Chicago River once flowed into Lake Michigan, which meant pollution reached the city’s drinking water. 9. She says the city reversed the flow of the Chicago River through the sanitary and shipping canal, completed in 1900. 10. She adds that St. Louis sued Chicago over waste sent downstream and lost, after which St. Louis built a filtration plant. 11. Melissa explains Chicago’s combined sewer system and defines CSO events as combined sewer overflow events during heavy rain. 12. She says the Metropolitan Water Reclamation District of Greater Chicago launched TARP in 1981 and plans for it to hold 17.5 billion gallons. 13. She notes that the EPA gave a recreational thumbs up for the Chicago River in 2012. 14. Steve McAvoy says he studies sediments more than the water column and uses a clamshell sampler on a string. 15. He says he samples five or six stations consistently over 10 years and has built a continuous record of organic contaminants, calcium, and magnesium. 16. He calls urban water chemistry an emerging field and ties it to acid rain dissolving concrete and making D.C. rivers saltier. 17. He describes siloxanes as synthetic compounds that nature does not make and says Europe has banned smaller versions in cosmetics while the United States has not. 18. He says lab studies on Anacostia water found embryo death, stress behavior, and improving PAHs and catfish cancer rates over time. 19. The conversation is an interview format with field-recorded river audio, then quieter conference-room discussion, and the energy stays explanatory and detailed. 20. People interested in Chicago water, river chemistry, and urban environmental monitoring should listen; people wanting a short, light chat about cities may skip it.

As heard by us

City water looks plain until the chemistry starts telling a different story.

A Chicago Riverwalk backdrop gives the episode immediate texture, but the real focus stays on urban water chemistry and the hard fact that water quality has to be tested, not guessed from appearances.

Read the full review in PlayNext →

Why you'd press play

Want a Riverwalk tour that turns into a lesson in how city water is tested and why it changes?

Read the full recommendation in PlayNext →

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