Reviving the Gulf Coast Dead Zone

Published Dec 1, 2020

What happens upstream… goes downstream. Dr. Rebecca Boehm explains how excess fertilizer on Midwest farms contributes to “dead zones” in the Gulf, and how to reverse course.

In this episode
  • What is the Gulf dead zone?
  • How are Midwest farming practices, mainly the use of fertilizer, impacting Gulf Coast Fisheries?
  • What are some of the economic solutions for farmers and fishers?
Timing and cues

Opener (0:00-0:31)
Intro (0:31-2:06)
Interview part 1(2:06-12:54)
Break (12:54-13:50)
Interview part 2 (13:50-22:37)
Ending segment throw (22:37-23:05)
Ending segment (23:05-27:54)
Outro (27:54-28:56)

Related content
Show credits

Editing and music: Brian Middleton
Research and writing: Jiayu Liang and Pamela Worth
Executive producer: Rich Hayes
Host: Colleen MacDonald

Full transcript

Colleen: Rebecca, welcome to the podcast.

Rebecca: Thank you for having me. I'm really glad to be here.

Colleen: Yeah. So you've been studying the environmental and economic impacts of the Gulf dead zone. And well, the term dead zone sounds kind of ominous. You've got some interesting ideas for solutions in there, but let's start just with a definition of dead zone because we're not talking about a cell phone dead zone here.

Rebecca: Right. Yeah. So a dead zone is an area in ocean water that is devoid of oxygen. So just like humans need oxygen to survive, there needs to be oxygen and ocean water for marine life to be healthy. And so a dead zone is an area where the oxygen levels are very low and that's resulting from nutrient imbalance, essentially, in the ocean water. And so the one that we focused on in our “Reviving the Dead Zone” report was the Gulf of Mexico dead zone which is along, you know, the Southeastern border of the United States. But these dead zones, they can be all over the world. They are all over the world. There's one in the Gulf of Oman in the Arabian Sea and there are many others. But we focused on the Gulf of Mexico dead zone because it is linked... its fate is linked very closely to agricultural production, north along the Mississippi River. And it is the second, typically the second largest in the world, but it varies from year to year.

Colleen: So what causes a dead zone?

Rebecca: Yeah, so as I said, agriculture is very tied into the fate of the Gulf of Mexico dead zone. So nitrogen is a really important nutrient in agricultural production. It ensures good crop yields and it is used a lot in the Midwestern corn and grain production. And the way that farmers typically grow those crops means that a lot of nitrogen leaves the farm and ends up in waterways. And that water carries the nitrogen downstream into the Gulf of Mexico. And so, earlier I said there's a delicate nutrient balance in ocean water, including for nitrogen. So there's a kind of Goldilocks, a right amount of nitrogen in the Gulf of Mexico that's good for marine life, good for fishermen. But the nitrogen that runs off farms in the Midwest ends up in the Gulf and is the leading contributor to the dead zone. That nitrogen coming down the Mississippi every single year, millions of tons, is what creates the dead zone.

Colleen: With all that excess nitrogen, what actually happens then?

Rebecca: Yeah, so once the excess nitrogen finds its way down from the Mississippi River and enters the Gulf of Mexico, it actually produces a lot of algae. Algae is basically plant life, microscopic plant life near the surface of water, ocean water. So the nitrogen actually stimulates more growth of that algae. But then there's this case, there's something called too much of a good thing. So nitrogen is necessary for algae to grow. Algae is what other marine life eat. So it's sort of the beginning of the food chain or the food web in the ocean, but too much of a good thing increases the algal growth, bacteria consume the algae and other species. They produce waste and the waste is what causes the oxygen levels to decrease in the Gulf of Mexico. So too much nitrogen, too much algae, too much waste, not enough oxygen, is sort of the simple way to think about it. It's a pretty complicated process. And so that's really all that nitrogen coming down the Mississippi river is fueling that algae growth and, and causing the dead zone.

Colleen: So this sounds to me like it is something that could be reversed.

Rebecca: Yes. Yes. Absolutely. As I said, agriculture is the leading cause of this problem in the dead zone. And so there are changes to agricultural production that could occur that would reduce the amount of nitrogen fertilizer that ends up in waterways. So one of those ways is cover cropping. So when farmers, you know, they're done for the season, they've grown their crops, farmers can leave their field barren. Planting cover crops, so a crop that just holds in the soil and is there in the time where the main production crop isn't growing can actually keep nitrogen in the soil and keep it from entering waterways. So you can imagine in the fall or winter, there's a heavy rain and that field is just soil, there's no plant life. Any nitrogen that might've been applied could wash off the farm through erosion and end up in a nearby stream or river and it also can leach into the groundwater. So you know, in the Midwest and all over there's aquifers under the ground and nitrogen can enter those aquifers and contaminate groundwater sources. So bottom line is we need to shift some of our agricultural practices to keep the nitrogen out of waterways, keep it on the farm if farmers are gonna use it.

Colleen: So what impact is the dead zone having for communities on the Gulf coast?

Rebecca: So the dead zone occurs every spring summer season. So it's not there all year, it disappears a part of the year. But when it is there, it happens to coincide with the shrimp harvest season. And so increasingly shrimpers sort of have to navigate around this giant dead zone in order to, you know, catch a profitable amount of shrimp. And what happens is the shrimp who may be in the dead zone, they try to leave it. So that forces some shrimp to congregate around the edges of the dead zone, which actually makes it easier for shrimpers to catch them, but also obviously it does affect reproduction of the shrimp.

And in some cases, there's been fewer shrimp to catch. It presents big challenges for shrimpers and other types of fishermen, fisher people in the Gulf. And the fishing industry is a huge industry all along the Gulf, both for commercial production, it supplies a lot of the seafood for restaurants, including New Orleans and all along the Gulf. And, you know, it's obviously important for the tourism industry. So the dead zone is really a problem for the Gulf coast economy that relies on, you know, healthy ocean waters so that it can function.

Colleen: Right. So aside from the economics of it, there's also sort of a cultural aspect to what's happening. Can you talk a little bit about the communities in these areas and what's happening there?

Rebecca: Yeah. In the course of doing the research for this report, we talked to a lot of people on the ground who are affected by the dead zone, who are also affected by hurricanes. This area has multiple big issues it's confronting. It’s a diverse group of people who are shrimping on the Gulf coast, who are fishing, and it ranges from indigenous communities who've lived along the shore for generations and there are also immigrants, especially Vietnamese immigrants who fled Vietnam during the Vietnam war who brought their fishing traditions with them to the U.S. And so there's a range of people who are living off of the Gulf waters and really need it to be healthy so that they can earn a livelihood, but also, continue on with some of their cultural traditions.

Colleen: So in the report, you talk about the economic benefits of getting the dead zone under control. And a lot of the nitrogen is coming from farms in the Midwest. So the solutions are gonna come from the Midwest, which is not the area that is experiencing the problems. So how do we come up with solutions that will incentivize farmers in the Midwest to adopt better practices that will help the Gulf coast?

Rebecca: Yeah that's a great question. And to bring in a little econ 101, when a third party is impacted by a transaction occurring, kind of somewhere else, economists call that an externality. So we have this big externality in the Gulf of Mexico. And as you say, that the solutions do come upstream. And so in our report, we've provided some policy recommendations to make it easier for farmers to adopt practices like cover crops, which I talked about earlier. And, those policies include one that was introduced last year called the agricultural Resilience Act. And so this bill provides funding and resources for farmers to help them adopt these practices because it's hard to a farmer, you know, once you get into doing the thing that you've been doing for a long time, it's hard to shift it. And there's also costs associated with changing how you plant things and how you manage your farm. And so bills like this are really geared toward making shifts that will help keep nitrogen out of waterways, make it easier for farmers to do that.

Colleen: Do you get the sense that farmers want to adopt different practices?

Rebecca: That's a great question. I do think there's an appetite for this. One piece of evidence I can share is that there's a program called the Conservation Stewardship Program the USDA operates and it helps farmers have this sort of whole-farm approach to preserving natural resources like soil, and water, and also it helps them to be more resilient to things like climate change. It helps them adopt practices that do that. And we've seen demand for that program far outstrips how much funding is available. So we think there is an appetite absolutely for this. And I think some of these practices that keep nitrogen on the farm, if it's used, these practices help farmers to be more resilient to climate change. You know, when there's a flood, if you have more organic matter, if you have roots in the soil, it's gonna reduce soil erosion on your land and it's gonna keep that soil on your farm so you can be productive long-term and the soil will hold more water so there's less damage to the farm in the case of an extreme flood. So there's benefits for farmers, but there's also benefits for climate and for water quality for some of these practices that can really reduce nitrogen losses from farms.


Colleen: I've read in the report summary that the solutions will actually save more money than they cost. So this seems like an economic win. Can you talk about that a little bit?

Rebecca: Yeah. So in our analysis, we looked at some recent estimates of how much it would cost for widespread adoption of these practices, like cover cropping and Prairie strict planting, and a few others. If we adopted those at a wide scale in the Midwest, how much would that cost? Because obviously, it's gonna cost them money. Again, farmers have to change the way they do what they're doing, and the costs of that, at least from a policy perspective, would be costs that the government would bear. So we'd be providing incentives or funding for farmers to do this. So we compared those costs to the costs of reducing the damage that the nitrogen causes in the Gulf of Mexico.

So we estimated the impact from the nitrogen on marine habitat and fishing stocks in the Gulf and we found that those benefits in some of our scenarios outweighed those costs that we would have to incur if we were to help farmers make these shifts. So we think getting new funding, getting farmers to adopt these new practices, it is always a challenge. It has been a challenge for a really long time, but what we show in our report is there'd be a major return on investment in the Gulf if we were to move on these policy options that we have to increase the adoption of these sustainable practices that are good for the climate and good for farmers. And I'll say that, in addition to the benefits to the Gulf, that we found that we identified in dollar terms, there's also benefits upstream that we didn't quantify. So we feel like the benefits that we calculated are sort of an underestimate of what the true economic benefits would be if we address this problem focused on the dead zone in the Gulf.

Rebecca: We've talked about the problem of Midwest farms in the runoff going all the way down into the Gulf of Mexico, but have you focused at all on nitrogen runoff closer to home and what happens there?

Rebecca: That is what I'm working on right now, actually. I'm so glad that...

Colleen: Really?

Rebecca: Yeah. So, you know, when we do UCS reports, we consult with researchers, you know, and we talked to a lot of people in the course of this report and many of them said, "Hey. You need to look at what's happening upstream because there's water quality issues all along the Mississippi River and near the farms where, you know, where this runoff and the nitrogen losses are happening." And so, we thought it made sense to do our next work in that area.

Colleen: So give me a sneak peek at what you're looking at and what some of the issues are that you're working on.

Rebecca: Yeah. So we're looking at Iowa because there's a lot of grain and corn production in Iowa and also a lot of livestock production. And so what we're looking at now is we're estimating how much nitrogen is used in both crop and livestock production in Iowa. And it's pretty astounding how many billions of pounds of nitrogen go into the system or, you know, the agricultural system in Iowa. And I should say, it may not be clear where the nitrogen comes from, from animals. It comes from their waste. And so, we're trying to quantify like how much is going into the system, how much is entering the waterways, and then what impacts that has on the water quality in Iowa.

Colleen: You're looking at... So there's the nitrogen that's runoff from fertilizer, but there's also nitrogen associated with livestock?

Rebecca: Yeah. So,according to our... This is a draft estimate. I'll give you the sneak peek. In Iowa, there are more livestock animals than humans and those livestock animals like beef cattle, and hogs, and chickens, they produce poop, waste, and that actually contains a lot of nitrogen. Just in our kind of preliminary estimates, you know, in one year in 2017, there were 88 million animals just in Iowa producing 117 billion pounds of manure in one year and then that manure has a lot of nitrogen in it. Nine hundred and ninety-nine million pounds. So that has to be stored somewhere. Something has to be done with it. And so oftentimes it's actually sprayed on land, on farmland, nearby farmland, and then the nitrogen can wash off into waterways, just like with fertilizer. So we've got, again, a lot of nitrogen from crop production and livestock going into the system in Iowa, and nitrogen very easily washes off farms and leaches into the soil into groundwater.

Colleen: So you're talking about this as leaching into water that, what potentially becomes drinking water?

Rebecca: Yes. Yes. That is exactly right. So Iowa relies, like all of us, on groundwater and surface water sources for drinking water. So...

Colleen: So does the nitrogen get filtered out?

Rebecca: Yes. So there are public water systems all over Iowa that have to check for nitrates. Nitrates is what you would find in groundwater or surface water, you know, if it's contaminated from agriculture or livestock production. So yeah, there's federal and state regulations that require monitoring for the nitrate levels. And if it gets to a certain level you have a problem for public health. And so there's a lot of money going into treating drinking water sources for nitrates. And I'll just stop there, I guess.

Colleen: Okay. Yeah. Because we don't wanna give away too much before the report comes out.

Rebecca: Yeah. Well, the only other thing I'll say is to connect it back to the Gulf is that when drinking water systems are treated for nitrates, the nitrates are taken out, they're removed from the drinking water, but then they're put back into surface water and then they end up downstream anyways.

Colleen: Why would they put it back?

Rebecca: It has to go somewhere. It ends up in surface waters and likely ends up in the Gulf of Mexico where we have the dead zone problem.

Colleen: So really we have to get a handle on this, we have to use less of it?

Rebecca: Yes. And a way to do that is some of these practices that we think are good for farmers, good for the climate, and good for soil, cover cropping, like I said.

Colleen: Rebecca, if I were gonna put you in charge of this whole large project to make our systems better, what is a timeline for actually making some of this stuff happen? It's not gonna be quick, but could it be done in 5 years, 10 years, 3 years?

Rebecca: Well, in the current political context, I think given the urgency of climate change, some of the things that we need to do need to happen in that 5 to 10-year period even though that seems quick for having sort of wide-scale shifts in how we grow corn and other crops in the Midwest, in that part of the country. So I think it's sort of... Probably, there's some things that can happen. We just have to make it happen. We need a self-fulfilling prophecy. We need an ambitious goal and we need to be ambitious because of the climate, so we should be.

Colleen: So there are many upsides to adopting these better practices, which is really good news, right? We can do it.

Rebecca: Yes, I think so. And as I said, there's appetite. There's appetite for it among farmers. I think there's some challenges that farmers face that have to be confronted and we need to talk honestly about those challenges and also in the context of the farm economy and crop prices and how that impacts how farmers are doing business. But I think there's some win-win-win scenarios that we need to make possible through federal policy action.

Colleen: Excellent. Well, Rebecca, thanks so much. I'm glad to have a podcast where we can end on an upbeat note. That doesn't happen a lot.

Rebecca: Yeah, especially right now. I'm hopeful. I'm an optimist, so yeah. It was great to talk to you, Colleen.

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