When city rivers get wild

(Intro music)

Hey there. Welcome back to the Scienceline podcast. I’m Jenaye Johnson, your host and the Multimedia Editor here at Scienceline.org. Make sure to subscribe to our show — whether that’s on Apple Podcasts, Spotify, Stitcher, or another platform that you prefer using.

Okay, so what’s on today’s agenda? For our beloved eco-lovers, we’ve got rivers. Plants. Floating habitats. And… Chicago? Though it seems counterintuitive, I’ve got a story for you that involves all of that, situated right in the heart of the Windy City. Let’s dive on in.

Jenaye Johnson: In November, I took a flight to Chicago.

JOHNSON: Okay I’m headed to my gate. I think I’m B12. (background of others in the airport)

FLIGHT ATTENDANT: The airplane is full, so if you do have a large bag, turn around. See if you can find a spot going forward.

Jenaye Johnson: My trip wasn’t for the city’s sports or food scene and certainly not for its weather [SARCASM]. I was more interested in a little pocket of the Chicago River known as the Wild Mile. It’s one of Chicago’s urban floating wetlands. 

(Walking…) 

JOHNSON: Okay, so I think we’re coming across the entrance to the Wild Mile. “Welcome to the Wild Mile!” So there’s a sign here, it’s so fascinating. “Home of the Chonk.” Okay so there’s a Chonk out here, which is a snapper turtle.

(Water splashing, grass rustling)

Jenaye Johnson: The Wild Mile is like a boardwalk — kind of. Except, instead of shops and carnival games lining the river, a beautiful stretch of lush plants entices visitors to take a stroll down its wooden planks. It’s perfect for watching sunrises or sunsets, kayaking and hosting summer field trips.

Jenaye Johnson: Most importantly, the Wild Mile is a floating garden that’s been providing animal habitats since installation began in 2017.

Jenaye Johnson: I’m Jenaye Johnson with Scienceline. We’re going to dig into how these urban wetlands work, how they’re being used, and if they can help solve our problems with dirty water.

(Music fade in + out)  

Jenaye Johnson: But let’s backtrack for a second. What on earth is a floating wetland? Is it in the sky? Is it a bog? Literally just land that’s wet?? [INCREDULOUS] 

(Scientific music starts)

Jenaye Johnson: Basically, a floating wetland is a community of native plants that sits together on top of water. They’re planted on a floating body of soil or degradable materials, like coconut fiber mats. And their roots live underwater. Wetlands occur naturally in the wild, but the ones we’re talking about today are made by people.

Jenaye Johnson: So wetlands of any kind are crucial for river health, mainly because the plant roots are powerful suctions. They can absorb some of the toxins that seep into the water. Mainly nitrogen and phosphorus (thanks, industrial waste [SARCASM]). And they’re the perfect homes for tiny fish which like to snuggle up with the plant roots. Other animals are attracted to the flowers themselves, like snapper turtles, birds and even bats!

(Scientific music fades out)

JOHNSON: There are bats here?? Apparently there are little brown bats and big brown bats. 

NICODEMUS: It is just such a place for exploration and I am routinely surprised by the things that I see.

Jenaye Johnson: That’s Phil Nicodemus. He’s the Director of Research at Urban Rivers. They’re the folks who designed and built the Wild Mile. He wasn’t able to tour the wetlands with me, but I got a chance to chat with him after my visit.

Jenaye Johnson: Phil and his team had a hunch that Chicago could stand to benefit from more wildlife in the city. So they gave it a shot. And that’s sort of how the Wild Mile project came about, so people like me could explore it. 

JOHNSON: Oh my gosh. There’s a tiny little fish here. Right when I got to the edge of the ramp, I spotted this tiny fish. It is sooo cute. It’s smaller than my pinky and my pinky—it’s pretty small. Let me tell you.

(Birds chirping)

JOHNSON: It’s a beautiful spot to birdwatch. Right now, all I’m seeing is geese. But there are probably so many other smaller bird species out here that I’m not noticing slash recognizing, which is totally fine.

Jenaye Johnson: Schools and summer camps host field trips on the Wild Mile too. Urban Rivers loves this. Kids and teens come by for a bit, spot some cool animals, and then … 

NICODEMUS: … they go tell their friends about it and they’re back a month later, with like three friends like, “this is where I saw the heron!” It’s infectious and it’s immediately obvious too.

Jenaye Johnson: Community engagement is part of the reason the Wild Mile even exists. Now, there are more literal reasons why it exists too [LAUGHING]. The floating wetland was proposed because it’s one of the few habitat options that actually fits in the Chicago River. When thinking of natural solutions, there are dozens to choose from. But wetlands are unique because you can just use the river water that’s available and go from there.

(Upbeat music starts)

Jenaye Johnson: And they’ve been able to put the benefits into numbers too. Let’s look at fish, for example. Since the creation of the Wild Mile, researchers have seen increases in several species, including bluntnose minnows, fathead minnows and round goby. They’re just 3 of 7 species that made a return. And sometimes it’s been a big difference. Let’s take the minnows. Before the Wild Mile, researchers who check fish populations might find one or two minnows per haul if they’re lucky. But in a recent haul — they found at least 15. That’s a major improvement.

Jenaye Johnson: Less carp were spotted around the wetlands too, which is a good thing. Those invasive carp have a really bad habit of eating up all the little guys and messing with the ecosystem’s balance.

Jenaye Johnson: Even healthy zooplankton have returned. A study found that for these really microscopic species that kinda look like see-through shrimp, the Wild Mile saw an uptick in them. The increase of these zooplankton was anywhere from 160 to over 270 percent! And that’s just since the Wild Mile officially opened.

(Upbeat music ends)

NICODEMUS: It’s really gotten to a point where it’s actually something to celebrate, and then, taking these lessons that we’ve learned and start to apply these to other areas of the river.

Jenaye Johnson: Aside from the Wild Mile, there are a few more urban wetland projects sprinkled throughout the US. And they’re just as important. 

Jenaye Johnson: The Charles River in Boston is one of them. Max Rome from the Charles River Watershed Association is super-invested in that initiative. He has been for the last six or seven years. His goal is to revitalize the river for small fish, make it clean again, and remind Boston residents of its beauty.   

ROME: There’s places kind of in the middle section of the river that are just incredibly beautiful, that are connected to wetlands and have all these flowering plant communities along, you know, along the banks of the river. And it broadens into this kind of gigantic, glittering sheet of water with the city of Cambridge on one side and the city of Boston on the other side.  

Jenaye Johnson: And the wetland he’s helped develop is full of stunning plants, like pale green bulrush, red hibiscus moscheutos, pink rose mallow and blue verbena.  

Jenaye Johnson: Runners exercise along the riverbank and folks bike to work. Kids fish there, too (ROME: “I wouldn’t necessarily eat the fish”). But it’s more than just a park. As we discussed, floating wetlands can change the environment for the better. Those plants I mentioned are pretty, but they also suck up lots of phosphorus. Max has even measured this — and can see them removing these toxins from the water, slowly and steadily. 

(Pensive music starts)

Jenaye Johnson: So where exactly is the future of floating wetlands headed? It’s a great question, but it depends on sooo many factors.  

Jenaye Johnson: For starters, money. Wetlands can cost hundreds of thousands of dollars. And those are just the small installations [SHOCKED]. Chicago’s Urban Rivers applied for multiple grants while they were still in their nonprofit infancy. They fundraised for years and received educational support from across the pond. Yeah, Britain. The Shedd Aquarium also started to lend a hand financially in 2018. The goal back in 2017 was to receive 100,000 dollars to start—and now, their budget has increased to 3 million.

Jenaye Johnson: Here’s Phil Nicodemus again. He says they went from… 

NICODEMUS: Humble beginnings to still pretty modest current circumstances. 

Jenaye Johnson: So for long-term investments, groups will have to seek out more money not just from the city, but from outside organizations that see the value in conservancy.

Jenaye Johnson: Other obstacles include city permits and maintenance of the space around the wetlands. That means no litter and making sure the fencing is secure. You’ve also got to ward off pesky bugs that can tear the plants up (lanternflies, looking at you). 

(Pensive music ends)

Jenaye Johnson: With enough support, it’s possible for floating wetlands to be present in more major cities across the country. The benefits are small but mighty. And current installations could be bigger in years to come. The Wild Mile is set to expand even more by July of 2024. That’s REALLY soon.

Jenaye Johnson: And if you’re interested, maybe you should stop by Chicago too. The people are pretty cool, but the Wild Mile? That’s where the magic happens. 

JOHNSON: So yeah. I have reached the end of my Wild Mile journey. So just a final note is… this is a gorgeous spot. You know, it just, it feels so alive. It feels like I have a peek into nature in a city where I don’t expect nature to be at all. 

(Birds chirping)

Jenaye Johnson: This episode was produced by Jenaye Johnson. The soundtracks “Glue&Glia” and “Floating Wetlands” were written and provided by Rah Hite. Thank you to Blue Dot Sessions for allowing us to use their music, “Lo Margin” and “The Maison.”

(Outro music fades in)

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Scienceline is a production of NYU’s Science, Health and Environmental Reporting Program. Our theme music is by Jahzzar at the Free Music Archive. And for more information, please visit us at Scienceline.org or shoot us an email at scienceline@gmail.com. See you next time!