Podcast Summary: Short Wave — The World Has a Groundwater Problem. Can We Solve It?

Date: March 24, 2026
Hosts: Emily Kwong, Burleigh McCoy
Guests: Hayes Kelman (Kansas farmer), Deborah Perrone (UC Santa Barbara), Mohammad Shamsadoha ("Shams", University College London), Filippo Menga (University of Bergamo)

Overview

This Short Wave episode, part of a water-themed series, examines the global crisis of groundwater depletion. Hosts Emily Kwong and Burleigh McCoy explore what aquifers are, why they matter, how scientists track their health, and what can be done to stop their decline. The episode features perspectives from farmers, engineers, and political geographers, offering a nuanced look into the intertwined science, data challenges, and social impacts of groundwater use.

Key Discussion Points & Insights

What Are Aquifers and Why Do They Matter?

• Aquifer Defined: "An aquifer is just an underground layer of rock or materials that holds water." (Burleigh McCoy, 00:31)
• Vital Resource: Groundwater from aquifers supplies about half the water people use globally. (Deborah Perrone, 00:52)
• Not a Bathtub: “It's more like water between rocks that gets to the surface through wells and springs.” (Deborah Perrone, 00:44)

The Ogallala Aquifer: A Farmer's Perspective

• Hayes Kelman’s Reality:
  • Noticed well levels dropping significantly during high school. “I started watching how certain wells were just dropping off significantly, how we were removing a sprinkler from... a certain area of land because we didn't have enough water.” (Hayes Kelman, 01:32)
  • The Ogallala, or High Plains Aquifer, spans eight states and is rapidly losing water.
• Impact: Farmers can’t reliably plan harvests because water availability now depends on unpredictable rainfall. (Burleigh McCoy, 02:11)

The Global State of Aquifers

• Massive Data Collection: Researchers analyzed close to 1,700 aquifers, covering about three-quarters of all land tapped for groundwater. (Burleigh McCoy, 04:24, 04:39)
• Findings:
  • About one-third of aquifers studied are losing water, sometimes at catastrophic rates. “Groundwater levels are going down.” (Deborah Perrone, 04:55)
  • Some are drying up entirely, risking drinking water, wetland habitats, and even causing land subsidence—“draining an aquifer can cause the land to actually sink.” (Deborah Perrone, 05:03)
  • On average, declines exceed four inches per year; in some, it’s over 20 inches per year. (Burleigh McCoy, 05:45)
• Domino Effect: When aquifers deplete, other local sources dry up too, creating cascading shortages in water supply. (Deborah Perrone, 06:19)
  • “You’re getting hit twice, you’re getting hit with supply…and then you’re also getting hit with demand.” (Deborah Perrone, 06:19)

The Challenge of Shared Resources

• Aquifers Cross Borders: Multiple countries often access the same underground water, complicating management and negotiation efforts. (Burleigh McCoy, 07:05)
• Supply vs. Demand: Although the world could have enough water, it's about how it’s used.
  • “Water withdrawals over time grow much faster than global population. So it has to do with our lifestyle.” (Filippo Menga, paraphrased by Shams, 07:47)

Data Problems: Tracking the Invisible

• Inconsistent Monitoring: Well data is hard to compare—some are checked daily, others monthly, each aquifer has varying numbers of monitoring wells. (Burleigh McCoy, 08:51)
• Reluctant Governments: “If a government doesn't want to do that or doesn't want to share their data, that's kind of it.” (Deborah Perrone, 08:36)
• The Data is Messy: “One of the hardest parts...was actually reconciling all the different data and trying to make sure that they're comparable across space and time.” (Deborah Perrone, 08:36)

Scientific Tools: Satellites and Gravity

• Alternative: Satellite Sensing: Scientists use paired satellites (like NASA’s GRACE mission) to detect gravitational changes—an indirect measure of water movement. (Shams, 09:11)
  • “...by measuring the distance between the two satellites, you can actually make out how much gravitational field on Earth's surface is changing.” (Shams, 09:11)
• Limitations: Satellites show changes, not absolute water availability, nor local specifics important to farmers. (Burleigh McCoy, 10:07)

Living With Less: The Farmer’s Dilemma

• Hayes Kelman: Working with hydrologists to determine sustainable usage—“they've figured out what amount of water we can pull from the aquifer to become stable because it does have a recharge rate.” (Hayes Kelman, 10:26)
• Economic Complications: Switching to less water-intensive crops (like milo) is hard if there’s no market for them. Water-saving could hurt the wider agricultural economy, affecting livestock and meatpacking, and entire local economies. (Burleigh McCoy, 10:50-11:20; Hayes Kelman, 11:20)
  • “Our economies are based around agriculture, and irrigation is a massive part of that agriculture.” (Hayes Kelman, 11:20)

International Solutions & Hopeful Trends

• Shared Management Example: The 2010 Guarani Aquifer agreement between Argentina, Brazil, Paraguay, and Uruguay aimed to share data and avoid harm but lacked enforceable quotas and has seen slow implementation. (Burleigh McCoy, 11:59)
  • Agreement’s goal: “...ensure multiple, reasonable, sustainable and equitable use of its water resources.” (Treaty, quoted in episode, 12:24)
• Signs of Improvement: In 16% of studied aquifers, water levels are increasing again, often where proactive water management (like reduced extraction) was put into practice. (Deborah Perrone, 12:39)
  • “So it’s not all doom and gloom. And I’m actually cautiously optimistic.” (Deborah Perrone, 12:57)
  • “It is possible, yeah, to turn the tides on our declining aquifers.” (Deborah Perrone, 13:06)

Notable Quotes & Memorable Moments

• Emily Kwong (Wondering Aloud): “Wow. Thank you, aquifers, for keeping us all alive.” (00:55)
• On Data Complexity: “The data is a complete mess.” (Deborah Perrone, 08:36)
• On the Future: “Everything we do is for our kids and for the future.” (Hayes Kelman, 10:47)
• On Water Management: “Everyone knows we need to use less water, but figuring out how is going to take a lot of time and a lot of agreement.” (Burleigh McCoy, 11:40)
• Cautious Optimism: “So it’s not all doom and gloom. And I’m actually cautiously optimistic.” (Deborah Perrone, 12:57)

Key Timestamps

• 00:31–01:54 — What is an aquifer? Hayes Kelman on witnessing water decline.
• 04:24–05:59 — Global aquifer study results; the downward trend and its consequences.
• 06:19–07:26 — Why droughts are “a double hit” and basics of shared aquifers.
• 08:36–09:02 — The messiness of aquifer data and the difficulties in global monitoring.
• 09:11–10:07 — Satellites and invisible groundwater: what we can (and can’t) know.
• 10:26–11:20 — Local water management, economic dilemmas for farmers.
• 11:59–12:34 — The Guarani Aquifer agreement: a rare instance of international cooperation.
• 12:39–13:10 — Evidence of positive trends and reasons for hope.

Final Takeaway

The episode highlights groundwater’s vital but endangered role, the global scope of the crisis, and the immense scientific and political challenges in fixing it. Solutions require collective action, honest data sharing, and lifestyle changes—offering hope, but no easy answers.