Day Zero: When the wells run dry

Summary

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Short Wave: "Day Zero: When the wells run dry"

NPR | March 23, 2026
Hosts: Regina Barber, Rachel Carlson
Length: ~14 minutes

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Episode Overview

In recognition of World Water Day, this episode explores the growing reality of "Day Zero"—the point at which urban water supplies run out. Hosts Regina Barber and Rachel Carlson, alongside expert guests and eyewitnesses, dive into the causes, consequences, and lived experiences of water shortages worldwide. The episode focuses on memorable crises in cities like Cape Town, Mexico City, Chennai, and Tehran, while challenging listeners to rethink their relationship with water amidst infrastructure challenges and climate change.

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Key Discussion Points & Insights

1. Water Scarcity: A Disappearing "Normal"

• Global Water Bankruptcy Declared (01:01)

  • Rachel quotes Kaveh Madani, Director, UN University Institute for Water, Environment and Health, announcing a "dawn of a new era, global water bankruptcy."
    • Quote: “For much of the world, normal is gone.” (00:58, Kaveh Madani)
  • The declaration calls for a fundamental rethink of how we value and manage water.

• Personal Connection

  • Madani shares the pain of seeing his home city Tehran face an accelerating water crisis:
    • Quote: “Even in my darkest projections, I was not thinking that Tehran would hit this day so early.” (01:49, Kaveh Madani)
  • Water shortages are now part of daily life and expected to worsen globally.

2. What "Day Zero" Looks Like: Learning from Cape Town

• Cape Town’s 2018 Water Crisis: From Hope to Rationing (04:19–05:17)

  • Erin Baker, journalist and Cape Town resident during the drought, describes the shift from hope to strict rationing.
    • Residents were limited to 50 liters (13 gallons) per day. (05:06)

• Breaking Down the Numbers

  • Average US daily use: 82 gallons/person; during Cape Town's crisis: just 13 gallons.
    • Quote: “That’s one 90 second shower, two liters of drinking water, […] one cooked meal, two washings of your hands, two brushing of your teeth, and one flush of the toilet.” (05:31, Erin Baker)
  • Even young children adapted discipline:
    • Quote: “No, Mommy, we can't... I can't shower. I can't take a bath today because of the water. Water issues.” (06:06, Erin Baker)

3. How Cities Reach Day Zero: Shared Patterns

• Four Common Factors (06:32)
  • Leaky infrastructure
  • Mismanagement
  • Depleting aquifers
  • Urban population growth (increasing demand)
• Plus: Climate Change
  • Geography professor Filippo Menga: “Climate change—an enormous sort of bonus card.” (07:01)

4. Infrastructure Failures and Inequity

• Mexico City: A Case Study in Water Loss (07:20)

  • Economist Manuel Pirlo: 30–35% of water lost to leaks. (07:28)
  • An additional 10% is stolen and sold by cartels (07:58), meaning up to 50% of water never reaches consumers.

• Global Scale of Waste

  • In the US: 1 trillion gallons/year lost to household leaks. (07:43)
  • Regina: “So there’s a big engineering problem and a financial one, right?” (07:54)

• Permanent Scarcity for Some

  • Many poor neighborhoods in cities like Mexico City or Cape Town have never had reliable public water:
    • Quote: “Those are the people that live in a day zero situation, always.” (08:32, Filippo Menga)
  • Low-income households may spend up to 20% of income on water (08:59).

• Inequity of Restrictions

  • Study: Wealthiest Cape Town households used 50x more water than the poorest (09:48).

  • Water restrictions applied equally, burdening those already frugal.

    • Quote: “Obviously they understand the value of water because it’s measured in backache.” (09:29, Erin Baker, on water haulers in shantytowns)

5. How Cape Town Avoided Total Collapse

• Emergency Measures and Luck

  • Built temporary desalination plants (10:19).
  • Ultimately, a timely shift in weather “saved” the city:
    • Quote: “What happened was that it started to rain.” (10:33, Filippo Menga)
    • Erin: “It was totally biblical. [...] You do have this sense of relief.” (10:42)
  • Regina: “But that’s not something you can count on in the future, right?” (10:53)

• What if COVID and Day Zero Coincided?

  • Erin notes that combining such water shortages with pandemic sanitation needs would have been “a freaking disaster.” (11:10)

6. Chronic Water Scarcity: Past Crisis, Present Condition

• Challenging the Language of "Crisis"

  • Kaveh Madani: If water "crisis" is ongoing for 50 years, it is no longer a crisis but a chronic, systemic challenge.
    • Quote: “A crisis is a shock [...] if it becomes chronic, it’s part of the system that you need to face.” (11:50, Kaveh Madani)

• Needed: Mindset Shift

  • Kaveh and Erin both emphasize the need to treat water as precious, not free or guaranteed.

    • Quote: “Whenever you have touched the [water] tab, [...] you have to get used to a new sort of life.” (12:30, Kaveh Madani)
    • Erin: “Even now, if I hear a dripping faucet, I have a visceral reaction to, like, this is precious stuff. We can’t let that go.” (12:39)

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Notable Quotes & Memorable Moments

• Kaveh Madani on the hopelessness of being right:
  • “I wish I was wrong. It’s miserable to [...] know that your compatriots are [...] suffering or going to suffer.” (01:50)
• Regina on Water Rationing in Perspective:
  • “How much is that? Like what can you do with 13 gallons?” (05:17)
• Erin on Water Carrying:
  • “They understand the value of water because it’s measured in backache.” (09:29)
• Filippo on Chronic Inequity:
  • “Those are the people that live in a day zero situation, always.” (08:32)
• Kaveh on Crisis Language:
  • “But how can something be a Crisis for almost 50 years? Maybe this is a wrong terminology for a chronic problem at this point.” (11:36)

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Timestamps for Key Segments

• 00:40 — Regina and Rachel introduce the focus on global water shortages
• 01:05 — UN’s declaration of “global water bankruptcy”
• 04:19 — Cape Town’s Day Zero story begins
• 05:06 — Water rationing: 13 gallons per person/day
• 06:32 — Four drivers of Day Zero: leaks, mismanagement, aquifers, urbanization; climate change as “bonus card”
• 07:28 — Manuel Pirlo on Mexico City’s leaking infrastructure
• 08:32 — Chronic day zero for poorest neighborhoods
• 09:48 — Water use inequality in Cape Town
• 10:19 — Emergency desalination & “messianic” rainfall saves Cape Town
• 11:21 — Water crisis + COVID = disaster scenario
• 11:36 — The crisis is now chronic
• 12:39 — Changing everyday water habits and perceptions

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Conclusion

“Day Zero: When the wells run dry” moves beyond alarming headlines to tell a human-centered, global story about water scarcity. The episode powerfully argues that water shortages are not temporary disruptions but an evolving, chronic feature of modern life—exacerbated by infrastructure failures, climate change, and deep inequalities. The vivid accounts from Cape Town and Mexico City, expert analysis, and personal stories all point to a broader imperative: we must fundamentally reassess and value water as the indispensable, vulnerable resource it is.

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Next episode preview:
Tomorrow’s show focuses on aquifers—the water beneath our feet.

Transcript

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[Regina Barber]

You're listening to Shortwave from NPR. Hey, Shortwavers. Regina Barber here with producer Rachel Carlson.

[Rachel Carlson]

Hi. Hey, Gina.

[Regina Barber]

Hey. So in honor of World Water Day, Ewan Burleigh, another producer here at Shortwave, are exploring the ways water touches our lives, from increasing water shortages around the world to how it's affecting agriculture and aquifers.

[Rachel Carlson]

And I've been looking specifically into that first part, shortages.

[Kaveh Madani]

For much of the world, normal is gone.

[Rachel Carlson]

Earlier this year, the United nations declared the dawn of a new era, global

[Kaveh Madani]

water bankruptcy, calling for a fundamental shift in how the global community understands our most vital resource, water.

[Rachel Carlson]

Kaveh Madani is the director of the UN Universities Institute for Water, Environment and Health. And that clip is from a press conference in January. But Kaveh's been thinking about water for way longer than that. He grew up in Tehran with two parents who worked in the water industry,

[Regina Barber]

which of course, is now experiencing more intense water crises because of the war.

[Rachel Carlson]

Yeah. And he says he's been sounding the alarm about water in Tehran for years.

[Kaveh Madani]

I'm known back home for a person who was warning about these days, so this is happening. And then media contacts me and says, how do you feel?

[Regina Barber]

And what does he say?

[Kaveh Madani]

I wish I was wrong. It's miserable to, to, to feel and to, to know that your compatriots are, are suffering or going to suffer. And the chaos, the, the fear, the stress. Even in my darkest projections, I was not thinking that Tehran would hit this day so early.

[Rachel Carlson]

And the longer this goes on, the closer Tehran could get to something called day zero, when a city or a place runs out of water.

[Regina Barber]

Right. We've seen places come close to day zero. Right. So Cape Town in South Africa, Mexico City, Chennai in India.

[Kaveh Madani]

Tehran is not the first place that has experienced a situation like this, and it won't be the last one.

[Regina Barber]

Today on the show, what happens when the taps run dry, how cities are coping and why. Experts say we're overdue for rethinking our relationship to water. You're listening to Shortwave, the science podcast broadcast from npr.

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[Regina Barber]

time I heard about Day Zero was in 2018 for Cape Town's water crisis.

[Rachel Carlson]

Yeah, Cape Town's a really big one and I want to go back even a little further to 2017. Cape Town was experiencing a huge drought. Some water restrictions were in place and people were starting to think about how to conserve water a little bit more.

[Erin Baker]

You don't have to shower every day. We shower every other day, every three days. Make the shower shorter.

[Rachel Carlson]

That's Erin Baker. She's a freelance journalist who lived in cape town from 2014 to 2021.

[Erin Baker]

Wow.

[Regina Barber]

She was there when all of this was going down.

[Rachel Carlson]

Yeah, and she remembers it all super vividly. Erin says in the midst of the drought a lot of people were holding out hope.

[Erin Baker]

Kind of like, well, the rains are going to come, the reservoirs will fill up.

[Rachel Carlson]

But they didn't.

[Erin Baker]

And the rains they kept not coming.

[Rachel Carlson]

On February 1, 2018, every resident in Cape Town was limited to a maximum of 50 liters, or about 13 gallons of water per person per day.

[Regina Barber]

How much is that? Like what can you do with 13 gallons?

[Rachel Carlson]

Not a ton. So the EPA says the average person in the US uses 82 gallons of water per day. So 13 gallons, that's one 90 second

[Erin Baker]

shower, two liters of drinking water. If you have a dog, you always have to counting your dog. That's one sink worth of Hand washed dishes or laundry? One or the other, not both. One cooked meal, two washings of your hands, two brushing of your teeth, and one flush of the toilet.

[Rachel Carlson]

So Erin is doing the math. She's making all of these calculations and trying to figure out, like, how many times do I really need to flush the toilet? Even her daughter, who's 7 or 8 at the time, is aware of it too.

[Erin Baker]

Like, no, Mommy, we can't. I can't shower. I can't take a bath today because of the water. Water issues.

[Kaveh Madani]

Wow.

[Regina Barber]

Yeah. So, like, even kids are taking personal responsibility.

[Rachel Carlson]

Yeah. I mean, Erin told me that the kids were learning about it in school and just all of these questions were circulating.

[Erin Baker]

Do you really want to use your precious water supply? Even if it's recycled water, do you really want to use it for the toilet?

[Regina Barber]

I want to break this down, though. Like, how does a city like Cape Town get to this point?

[Rachel Carlson]

When it comes to day zero, the exact circumstances of every city are different, but there are a few things that they tend to have in common. Among them, leaky infrastructure, mismanagement of water, depleting aquifers, and more people living in cities, meaning more demand for water in concentrated regions.

[Regina Barber]

And climate change.

[Rachel Carlson]

And climate change, Yeah. I talked to Filippo Menga. He's a professor of geography at the University of Bergamo in Italy. And he referred to climate change as

[Filippo Menga]

an enormous sort of bonus card.

[Rachel Carlson]

Really? Not the bonus card you want when your deck already includes all those other things.

[Regina Barber]

Yeah. And I know we're going to get into, like, one of those factors. Aquifers. That's tomorrow's episode. But, Rachel, maybe for today, can we just zoom into that bad infrastructure part?

[Rachel Carlson]

Yeah. I talked about this with Manuel Pirlo. He's an economist in Mexico City, where there's been an ongoing water crisis for years.

[Filippo Menga]

30 to 35% of the available water gets lost in leaks in the public distribution system. Yes.

[Regina Barber]

Wait, like leaky pipes?

[Rachel Carlson]

Yeah. And that's a global problem. In the US the EPA estimates around 1 trillion gallons of water each year are wasted just from household leaks.

[Regina Barber]

Wow.

[Rachel Carlson]

So there's a big engineering problem and

[Regina Barber]

a financial one, right?

[Rachel Carlson]

Yeah. And then on top of that, in

[Filippo Menga]

Mexico City, another 10% gets stolen from the system.

[Regina Barber]

What does he mean by stolen?

[Rachel Carlson]

When water is scarce, it's also profitable. So cartels or groups will steal water from pipes and then sell them for a lot of money.

[Filippo Menga]

So you have around 50% of the water lost on its way to the consumers.

[Rachel Carlson]

Other estimates say it's around 40%. But either way, the distribution of who is actually getting water usually isn't equal.

[Filippo Menga]

Large parts of the population do not get water at all in Mexico City. They are not attached connected with the public water system. They've never been connected. Those are the people that live in a day zero situation. Always.

[Regina Barber]

Okay, so for some people, day zero has been here for years already.

[Rachel Carlson]

Yeah, exactly.

[Filippo Menga]

Lower income groups spent a lot of their family income in water, sometimes 20% of their whole income. They are the ones who suffer the most. But the problem affects the whole city, there's no question about that.

[Rachel Carlson]

That's something Erin brought up, too, especially for a lot of less wealthy people in Cape Town and the surrounding areas. They were already experiencing water scarcity for years before the drought and before water restrictions went into place.

[Erin Baker]

So the shanty towns and the townships, they were not wasting water because these were the people who had to fill buckets to take the water to their house. So, so obviously they understand the value of water because it's measured in backache.

[Rachel Carlson]

There was one study published in the journal Nature a couple years ago, and it looked at all of this after the fact. They used a model to estimate that the wealthiest households in Cape Town were using over 50 times more water than the lowest income houses they looked at. But everyone had to cut down on their water use or risk being fined, even people who weren't using very much to begin with.

[Regina Barber]

Wow. So even the restrictions weren't necessarily equitable either.

[Rachel Carlson]

Exactly.

[Regina Barber]

So what did end up happening in Cape Town in 2018?

[Rachel Carlson]

Cape Town City officials knew they were in big trouble when it came to water. So they'd started building temporary desalination plants as an emergency measure to have more fresh water for people to use for drinking. But what actually let the city avoid

[Filippo Menga]

day zero, what happened was that it started to rain.

[Regina Barber]

Wow.

[Rachel Carlson]

Filippo called it a messianic rain. And I mentioned that to Aaron and she agreed.

[Erin Baker]

Oh, it felt so good. Yeah, it's totally. It was totally biblical. I mean, we were all. I mean, it's not like we were dancing in the streets. It was cold. But, I mean, you do have this sense of relief.

[Regina Barber]

Oh, but that's not something you can count on in the future, right?

[Rachel Carlson]

Especially not with climate change. They were super lucky. And Erin says a few years later, during COVID all she could think about was how many times every single day people were washing their hands.

[Regina Barber]

Yeah.

[Erin Baker]

And I was just thinking, if we had had the water crisis combined with COVID and the sanitary measures that you needed, that would have been a freaking disaster.

[Rachel Carlson]

So you can kind of hear Gina Aaron's mindset around water has flipped since 2017. And that's the kind of thing Kaveh says needs to happen for all of us. Because people often assume water is abundant, or maybe at worst, they say there's a crisis.

[Kaveh Madani]

But how can something be a Crisis for almost 50 years? Maybe this is a wrong terminology for a chronic problem at this point.

[Rachel Carlson]

Kaveh says maybe we're past the point of crisis.

[Kaveh Madani]

A crisis is a shock. It's a temporary deviation from a normal that you're used to. But if the crisis is there forever, if it becomes chronic, it's part of the system. That's an essential element of the system that you need to face.

[Regina Barber]

Okay, so he's saying this situation isn't temporary, so we need to, like, completely change our approach to water.

[Rachel Carlson]

Exactly. And my conversations with people like Kaveh who study water and people like Erin who understand how precious water water is all came down to one thing. We treat water like it's free, but we can't.

[Kaveh Madani]

Whenever you have, you have touched the tablet, you have had water, and all of a sudden you have to get used to a new sort of life.

[Erin Baker]

Even now, if I hear a dripping faucet, I have a visceral reaction to, like, this is precious stuff. We can't. We can't let that go.

[Regina Barber]

Rachel, thank you so much for bringing us this reporting.

[Rachel Carlson]

Yeah, thank you, Gina.

[Regina Barber]

If you like this episode, tune in tomorrow. We've got another water story for you, this time on Aquifers, the water beneath your feet. And if you have a second, could you share this episode with a friend? It helps us grow and it helps us continue to make episodes like this one. This episode was produced by Bert Shirley McCoy and edited by our showrunner, Rebecca Ramirez. It was fact checked by Aru Nair. The audio engineer was Jimmy Keeley. I'm Regina Barber. Thank you for listening to Short Wave from NPR.

[Erin Baker]

Foreign.

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