Short Wave - Give Rivers Space: The Simple Flood Risk Fix

Episode Date: June 14, 2023

With much of California's massive snowpack yet to melt, downstream communities remain on high alert for flooding. Hundreds of homes were destroyed or damaged during the record-breaking winter, which tested the state's aging flood infrastructure. To prevent flooding, communities often raise levees next to rivers higher and higher. Today, NPR climate correspondent Lauren Sommer talks about a new approach: just giving rivers some space to flow. Got questions about science? Email us at [e-mail]. We'd love to hear from you!See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Hey, short wavers, Regina Barbara here. There's still a lot of snow in California's mountains. It's been a year for the record books. A year that has showed how a lot of infrastructure for floods just isn't ready to handle all that water. It's been a heartbreaking weekend for the residents of Pahoro in Monterey County. The levee breach Friday put the town underwater. Hundreds of homes were flooded.

And a lot of communities are asking how they can protect. themselves from disasters like these. So we brought NPR's climate correspondent Lauren Summer. She's been reporting on a solution. Hey, Lauren. Hey, Regina. And yes, the whole idea behind this is to work with nature instead of trying to contain it. So there were two communities that flooded this winter, Pajaro and Planaada. And they had a lot in common. They're both lower income, largely home to farm workers, and both flooded when levees broke. So what went wrong with these levees? Like, was the water too high? Yeah, in Paharo, you know, the levy was old and it needed improving and it just wasn't up to handling a major flood. And as a lower income area, it just didn't get enough

attention and resources for its infrastructure. I actually went to another town that has a lot in common with those two towns. Grayson is in California's Central Valley. It's also home to a lot of farm workers and it's right next to a river. You know, naturally when you live by the river, you're nervous when you see the water rising. That's John Mataka. He's a longtime resident there. We were standing next to the San Joaquin River, which was just swollen with water. It was right up next to the houses at the edge of town.

How long were they on alert for these floods? It was for months due to all that snow melting out of the mountains. And John said his community also lacks investment in its infrastructure. There's not just farm workers and people that don't speak English living in these communities. We're people. We're human. We've got needs. And you need to invest in our communities. But, you know, even with all that water there this year, Mataka has felt a little bit better because of something that was invested in nearby. So I believe that it saved our community for some drastic flooding this year. What did they do differently there? So upriver from town,

there are a bunch of levees that could have been raised higher. But instead, the levees were taken down. Basically, they gave the river some room to flood, and a growing number of projects are doing the same thing around the country. Today on the show, flood risk is getting worse with climate change. To protect communities, maybe rivers just need a little space. You're listening to Shortwave from NPR. Okay, Lauren, so you went to see a very different kind of project that can help stop flooding. One that's about letting rivers do their thing. What does it look like?

Yeah, so because of all the rain and snow in California, the thing that rivers wanted to do this spring was flood. And the place I went, which was a few miles up River of Grayson, was just full of water. I was there with John Carlin. He works at the River Restoration Nonprofit River Partners. We'd love to see the flood water on our property. We'd love to see a flood on our property. Okay. It sounds weird, but that's actually what it was designed to do. The water over there just covered this huge area, hundreds of acres, and it was kind of going halfway up all these willow and cottonwood trees, just submerging them, and we actually had to head out into a boat to see it.

Yeah, this was like a tomato field, and now it feels like we're out in the middle of Louisiana and a swamp somewhere. So how were they able to let the river flood safely? Right, yeah, so this land used to be farm fields. It was agricultural land, but it was only protected from the river by these earthen berms, basically these big piles of dirt that hold the water back. Okay. And the landowner had all these problems with flooding. So river partners struck a deal to buy it.

And what they did is, they took the berms down that were holding back the river. And instead, they were relying on these levees and berms that are acres away from the river. So the project is actually known as a levee setback. And that creates this wide space, which is a floodplain. So now normally the river is just flowing down its normal channel, but when there's a lot of water, it spills over into this floodplain. Yeah, most of the year the floodplain is dry and it's been restored with all these native plants and trees. Oh, actually, can we do a quick detour about bunnies? Of course.

Okay, so there are these patches of higher ground that they created too, because there's wildlife that needs a place to go when the water rises. And one of those animals is the riparian brush rabbit. But it's kind of like a foot long. It's very endangered, too. Oh, okay. And so down river from there, the water has actually risen so much that a lot of the rabbits have been getting stranded on these little islands of land. Oh, no.

Yeah, they're surrounded by water. So wildlife officials have actually been rescuing them. Okay, so emergency bunny rescuers? Yep. Yeah, it's a job. They actually go around in kayaks and find the rabbits. And some rabbits have actually been plucked from the branches of trees because that's the only place they could go. Oh, no. But, you know, it actually raises a good point because this kind of habitat, this riverfront habitat, it's really rare.

They don't have a lot of places to go because 95% of it has been destroyed in the Central Valley because people have put in farms and cities. And so when there is this wide floodplain like this where the river spreads out and slows down, it's actually really good for young salmon. for birds and a lot of other animals. Got it. So it sounds like wildlife is used to having these flooded areas where the water can spread out. Yeah, absolutely. They're adapted to it. And that's what John described to me while I was there. We're looking back in time. We're looking at what this river used to look like 100 years ago. You know, the era of building dams, it changed everything. You know, rivers used to seasonally just spread out like this before we controlled the flow of water. And so the floodplain is really what the natural cycle is.

And so how does this help the people downstream who are worried about flooding? So the idea is that allowing the water to spread out and giving it some room up here will take the pressure off some of the levees downstream. So it's kind of like extra capacity to hold some of that flood water. I mean, it's tough to show that this one project stopped a flood in Grayson this year. It's not quite that clear cut. But if there are enough projects like this, it can help improve flood safety on a lot of lot of the river. So that brings up the question I have. This was a case where it sounds like the landowner wanted to sell the land, but waterfront property is valuable and plenty of people live there.

It's got to be tough to do a lot of projects like this. Yeah, I mean, that's a huge issue, especially if it's a community of homes that are already there. I mean, there are projects that have done buyouts to buy people out, but as you can imagine, you know, some people will have no interest in leaving their homes. I actually spoke to Julie Rentner, who is president of River Partners, And she says, doing this outside of cities makes the most sense. We have low-hanging fruit where we haven't yet urbanized this floodplain. Those are the spots we really need to prioritize moving on right away before it gets stressful. But, you know, the hard part about that is if you want to build these projects with funding from the federal agency that oversees levies,

which is the U.S. Army Corps of Engineers, they traditionally look at this very narrowly, which is they use a cost-benefit analysis. Basically, they say, is the stuff you're protecting right behind the levy worth more than the cost of building the project? Okay, huh. So it's a rural area. So maybe the land values are lower. And in that case, the math doesn't work out. The land is worth less than the cost of doing the whole construction project. Yeah, exactly.

There is a movement to change that, which the Biden administration is pushing. It's being called engineering with nature. So, you know, maybe in the future, projects could potentially value, other benefits in that equation, too, like the benefits of restoring habitat for wildlife, because otherwise these levy setbacks are really hard to do with that pot of federal funding. And, you know, the other big hurdle is just regulatory. All the laws and regulations were written to keep levies in place. You know, keep them there, keep them maintained, don't move them, don't take them down.

And as Julie told me, you know, the permitting process takes a really long time. We have to find ways to do this more efficiently. It's not okay for it to take 25 years to. undo the paperwork that we put in place a generation or two ago around how we want the world to look. You know, it actually takes an act of Congress to take down a levy that's overseen by the Federal Army Corps of engineers. Wow. Okay. So with all that, it's a solution for places like Grace in California, but will we see a lot more of these projects as a climate solution around the country? They are definitely happening in a lot more places now because, you know, money is going to have to be

spent either way. In the Central Valley alone, it will take as much as 30 billion, dollars over the next 30 years to get flood safety up to par, and that's mostly with traditional levees and flood projects. And concrete infrastructure, you know what people call gray infrastructure, it's much less adaptable to climate change because it's really only built for a certain amount of water. As the climate gets hotter, though, you know, rainfall is getting more intense when there are storms. So that's why there's this interest in working with nature's natural patterns, instead of only continuing this kind of arms race, basically, to contain all that water. Lauren, thank you so much for bringing us this.

Thanks for having me. This episode was produced by Brett Hansen, edited by our managing producer Rebecca Ramirez and fact-checked by Lauren Summer. Thank you, Lauren. Robert Rodriguez was our audio engineer this episode. Beth Donovan is our senior director, and Anya Grenman is our senior vice president of programming. I'm Regina Barber. Thanks for listening to Shortwave. from NPR.