When workers dug up a street in Flint, Michigan, they discovered something that nobody expected – and it explains alot about America’s water problems.
Sometimes the biggest discoveries happen by accident. Like when Alexander Fleming left a petri dish out and accidentally discovered penicillin. Or when a microwave engineer noticed a chocolate bar melting in his pocket and invented microwave cooking.
But the accidental discovery in Flint, Michigan wasn’t nearly as helpful. In fact, it was pretty terrifying.
In 2019, city workers were digging up old water pipes on Kearsley Street to replace them with new ones. This was part of the big effort to fix Flint’s water system after the lead contamination crisis that made national news.
What they found underground made everyone stop and stare.
The “pipes” they pulled out of the ground weren’t really pipes at all. They were more like cardboard tubes that had been wrapped in some kind of tar paper and buried in the dirt decades ago.
Wait, Cardboard Pipes Are Actually a Thing?
Before you think this sounds completely crazy, cardboard water pipes were actually used in some places during the mid-1900s. They were called “fiber conduit” or “bituminous fiber pipe,” and they were made from compressed wood pulp mixed with coal tar.
The idea was that these pipes would be cheaper than metal ones and wouldn’t rust like iron pipes did. Companies that made them claimed they would last 50 years or more.
Spoiler alert: they didn’t.
What Flint workers found were pipes that had started falling apart decades ago. Some had completely collapsed. Others had holes big enough to stick your fist through. A few had literally turned back into something that looked like wet cardboard.
How Did Nobody Know About This?
Here’s the crazy part – city records showed these sections of pipe as “cast iron” or “ceramic tile.” Nobody in the current city government had any idea that cardboard pipes existed under their streets.
The pipes had been installed sometime in the 1950s or 1960s, when Flint was a booming auto manufacturing city. Back then, the city was growing fast and needed to expand its water system quickly and cheaply.
Some contractor apparently convinced city officials that these fiber pipes were just as good as traditional materials but cost alot less. The pipes got installed, covered up with dirt, and forgotten about.
For decades, nobody thought to question what was actually underground. As long as water came out when people turned on their taps, everything seemed fine.
Mike Glasgow, who worked for Flint’s water department for years, told reporters he was shocked when they started finding the cardboard pipes. “In all my time working on water systems, I had never seen anything like it,” he said.
The Gross Reality of What Was Happening
Think about what it means to have cardboard pipes carrying your drinking water for 60+ years.
These pipes had been underground since the Eisenhower administration. They’d been through countless freeze-thaw cycles, floods, construction projects, and everything else that happens underground in a Rust Belt city.
The cardboard material had been slowly breaking down for decades. Pieces of it were flowing through the water system and coming out of people’s taps. The tar coating was leaching chemicals into the drinking water. And because the pipes had holes and cracks everywhere, contaminated groundwater was seeping in.
Dr Laura Sullivan from Michigan State University, who studied Flint’s water crisis, explained it this way: “Imagine trying to drink through a straw that’s made of wet newspaper. That’s basically what was happening.”
Why This Explains So Much
The cardboard pipe discovery helped explain some of the weird problems Flint had been having with its water for years, even before the lead crisis that made headlines.
Residents had complained about:
- Water that tasted like dirt or paper
- Brown or yellow water coming out of taps
- Weird smells that nobody could identify
- Water pressure that would randomly drop for no apparent reason
City officials had blamed these problems on “aging infrastructure” or “seasonal variations.” They never imagined that parts of their water system were literally made of decomposing cardboard.
The cardboard pipes also made the lead contamination crisis much worse. When the city switched water sources in 2014, the new water was more acidic and ate away at pipe materials faster. The cardboard pipes basically disintegrated, releasing decades worth of accumulated junk into the water system all at once.
Other Cities Started Checking Their Records
After news about Flint’s cardboard pipes got out, other cities started wondering what might be buried under their streets.
It turns out Flint wasn’t the only place that used these pipes. Cities across the Midwest and Northeast had experimented with fiber pipes during the post-World War II construction boom.
Detroit found sections of cardboard pipe in some neighborhoods. Parts of Cleveland had them too. Even some suburbs of Chicago discovered they had miles of these pipes that nobody knew about.
Most cities had better record-keeping than Flint, but not all of them. And even in places with good records, the maps sometimes lied. Contractors didn’t always install what they were supposed too, especially if they could save money by using cheaper materials.
The Cover-Up That Wasn’t Really a Cover-Up
Here’s what’s really wild about this story – nobody was actually trying to hide the cardboard pipes. It wasn’t some big conspiracy.
The pipes were installed legally, with permits, by licensed contractors. City inspectors probably even approved them at the time. The fiber pipe companies had legitimate businesses and advertised in trade magazines.
The problem was that over the decades, everyone involved forgot or retired or died. The companies that made the pipes went out of business. The city workers who installed them moved on to other jobs. The records got misfiled or lost.
By the time problems started showing up, nobody was left who remembered what was actually underground.
This is actually a bigger problem than it sounds like. Lots of cities have infrastructure that’s 50, 60, or even 100 years old. The people who built it are long gone, and sometimes the records aren’t as accurate as everyone assumes.
What Happened Next
Once Flint discovered the cardboard pipes, they had to figure out where else these things might be hiding. This meant digging up streets randomly to see what was actually underground, not just what the maps said was there.
They found cardboard pipes in dozens of locations that records showed as having “iron” or “steel” pipes. Some entire neighborhoods had been getting their water through decomposing cardboard for decades.
The city had to replace all of it, which added millions of dollars to their water system repair costs. And since they couldn’t trust their own records anymore, they had to physically inspect thousands of pipe connections to make sure they knew what they were actually working with.
The Bigger Lesson About Infrastructure
The cardboard pipe discovery in Flint is really a story about something much bigger – America’s aging infrastructure and how little we actually know about what we built decades ago.
Cities across the country are full of pipes, bridges, electrical systems, and other infrastructure that’s older than anyone who currently works for the government. The original builders are gone, the companies that made the materials are out of business, and sometimes the records are incomplete or wrong.
This creates a scary situation where cities are maintaining systems they don’t fully understand, using maps that might not be accurate, and making assumptions about materials that could be completely wrong.
Why This Could Happen Anywhere
Before you feel too smug about Flint’s problems, consider this: your city probably has infrastructure mysteries too.
Most American cities built major water, sewer, and electrical systems in the 1950s and 1960s. That was an era of rapid growth, experimental materials, and sometimes questionable construction practices.
Some cities used asbestos cement pipes that are now crumbling. Others used cast iron pipes that have corroded away to almost nothing. A few experimented with early plastic pipes that turned out to have much shorter lifespans than expected.
The scary truth is that most cities don’t actually know exactly what’s underground. They have maps and records that are probably mostly right, but there are always surprises when they start digging.
What You Can Do
This story isn’t meant to make you paranoid about your water, but it is a good reminder that infrastructure problems can hide for decades before anyone notices them.
Here’s what regular people can do:
Pay attention to your water: If it tastes weird, looks funny, or smells strange, don’t just ignore it. Call your water company and ask them to investigate.
Support infrastructure spending: It’s not the most exciting political issue, but cities need money to maintain and replace aging water systems.
Get your water tested: You can buy test kits or hire professionals to check what’s actually coming out of your tap, regardless of what the city says should be there.
Ask questions: If you’re curious about your local water system, most cities have people you can call who will explain where your water comes from and how it gets treated.
The Silver Lining
The one good thing about Flint’s cardboard pipe discovery is that it forced the city to completely rebuild its water system with modern materials and better record-keeping.
New pipes are made of materials that are designed to last 100+ years. Digital records mean future city workers will know exactly what’s underground. And the whole experience has made Flint more carefull about water quality than most cities.
In a weird way, accidentally discovering that your pipes are made of cardboard might be better than never finding out at all. At least then you can fix the problem instead of wondering why your water tastes like wet newspaper.
The Bottom Line
The next time you turn on your tap and clean water comes out, remember that there’s a whole hidden world of pipes, pumps, and treatment systems making that possible.
Most of the time, this hidden infrastructure works pretty well. But sometimes, city workers dig up a street and discover that part of the system is held together with what amounts to 60-year-old cardboard and hope.
Flint’s cardboard pipe discovery is a reminder that our cities are built on layers of decisions made by people who are no longer around to explain them. Sometimes those decisions were good ones. Sometimes they were disasters waiting to happen.
The important thing is to keep checking, keep testing, and keep asking questions. Because if we’ve learned anything from Flint’s experience, it’s that you can’t always trust that what’s supposed to be underground is actually what’s down there.
This article is based on reports from Flint city workers, Michigan State University research on infrastructure failures, and documentation of fiber pipe use in mid-20th century water systems. While “cardboard pipes” is a simplified term, the technical name for these materials was bituminous fiber pipe or fiber conduit, made from compressed wood pulp and coal tar.
This article is for informational purposes only and does not constitute professional advice about water systems or infrastructure. Readers with concerns about their local water quality should contact their municipal water department or consult with qualified professionals.h mentioned reflects ongoing academic and scientific work. Readers are encouraged to consult professionals for specific health concerns.
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