‘It’s getting worse’ – U.S. failing to stem tide of harmful farm pollutants in Mississippi River

by Keith Schneider | The New Lede, Iowa Capital Dispatch
April 21, 2024

VENICE, Louisiana —  Kindra Arnesen is a 46-year-old commercial fishing boat operator who has spent most of her life among the pelicans and bayous of southern Louisiana, near the juncture where the 2,350-mile-long Mississippi River ends at the Gulf of Mexico.

Clark Porter is a 62-year-old farmer who lives in north-central Iowa where he spends part of his day working as an environmental specialist for the state and the other part raising corn and soybeans on hundreds of acres that his family has owned for over a century.

Though they’ve never met, and live 1,100 miles apart, Arnesen and Porter share a troubling kinship – both of their communities are tied to a deepening water pollution crisis that is fouling the environment and putting public health in peril across multiple U.S. states.

Arnesen’s home lies near an oxygen-depleted expanse of the northern Gulf known as the “dead zone,” where dying algae blooms triggered by contaminants flowing out of the Mississippi River choke off oxygen, suffocating shrimp and other marine life.

Porter’s farm is positioned at the center of the Upper Mississippi River Basin, where streams and other surface waters saturated with farm wastes flood into the big river, and contaminated groundwater permeates drinking water wells. Cancer incidence in Iowa is among the nation’s highest, and is rising.

The culprit at the center of it all is a colossal tide of fertilizer and animal manure that runs off fields in Iowa and other farm states to find its way into the Mississippi River. The same agricultural pollution problems are plaguing other iconic U.S. waterways, including Chesapeake Bay and Lake Erie.

U.S. farmers use more fertilizer and spread more manure than in most other countries, accounting for roughly 10% of global fertilizer use, behind China and India. But while the nutrients contained in animal manure and fertilizer are known to nourish crop growth, the resulting nitrogen and phosphorous that end up in waterways are known to create severe health problems for people.

A grand government plan to address the problem has cost taxpayers billions of dollars with minimal results so far, and nowhere is the problem more pronounced than in the Mississippi River Basin.

The reasons for the persistent pollution problem are multi-fold, including strong industry opposition to regulations to control the farm contaminants, and a perverse system in which some government programs incentivize farming practices that add to the pollution even as other government programs try to induce farmers to reduce the pollution.

“You’re talking about systemic dysfunction,” said Matt Liebman, professor emeritus of agronomy and sustainable agriculture at Iowa State University.

An ‘extraordinary task’

The U.S. Environmental Protection Agency (EPA) has called nutrient pollution “the single greatest challenge to our nation’s water quality,” and acknowledges that much of the nutrient pollution flowing into the northern Gulf originates on agricultural land. For nearly 30 years the agency has led a task force that includes tribal leaders and officials from 12 states working together to try to impede fertilizer and manure from running off cropland at the center of the country.

The task force has set a goal of reducing the five-year average extent of the hypoxic zone in the Gulf to less than 2,000 square miles by 2035. To meet that goal, the task force has been trying to cut total nitrogen and phosphorous loads in the water 20% by 2025 and 48% by 2035.

Key to the effort is a suite of voluntary conservation practices promoted by the U.S. Department of Agriculture (USDA) aimed at reducing the pollution, including idling land, not tilling before planting, using cover crops to protect the soil, and building retention ponds and wetlands to collect and absorb nitrogen. Farmers are also encouraged to plant nitrogen-absorbing vegetation in buffer strips along streams. The USDA said in 2015 that the conservation programs were making headway, but in 2022 reported that efforts to reduce flows of nitrogen and phosphorus off farmland were showing negligible results.

The EPA did not respond to a request for an interview. The USDA said in an email message that in separate reports in 2017 and 2022, agency researchers “documented some promising trends nationally for reducing nutrient losses, such as increases in cover crop use, increased use of advanced technologies such as use of enhanced efficiency fertilizers and use of variable rate fertilizer application technologies, and a slight increase in soil testing. However, the key finding was that there was a national decline in nutrient management over a decade resulting in an increased loss of subsurface nitrogen and soluble phosphorus loss.”

The U.S. has spent more than $30 billion since 1997 on efforts to clean up the Mississippi Basin, but in a 2023 progress report to Congress the EPA said much more work is needed. Reducing nutrient loads is “an extraordinary task,” the EPA report states. “Attempts to intercept, treat, or otherwise address nutrients after they are mobilized on the landscape are complex, difficult, and often costly.”

Last summer, the oxygen-depleted Gulf “hypoxic” zone measured roughly 3,000 square miles, which was smaller than in previous years. But experts said that was mostly due to a deep drought in the Midwest that reduced the river’s flow into the Gulf. In 2021, after a wet spring and summer, the Gulf’s hypoxic zone was close to 6,000 square miles.

And despite government efforts, nutrient loads to the Gulf in 2020 tallied roughly 3.7 billion pounds of nitrogen and 452 million pounds of phosphorous from what the government calls the Mississippi/Atchafalaya River Basin (MARB), the task force said in its report. That was up from total MARB nutrient loads to the Gulf in 2017, which were approximately 3.3 billion pounds of nitrogen and 314 million pounds of phosphorus, according to the 2019 task force progress report.

“More nitrogen is coming off the fields,” said R. Eugene Turner, professor emeritus of oceanography and coastal sciences at Louisiana State University and an expert on the Gulf hypoxic zone. “On average the load and the concentrations of nitrogen in the river are not coming down.”

The primary cause is more nitrogen pouring off the land from the big upper Mississippi River Basin farm states. From 2010 to 2022, for instance, the average annual amount of nitrogen leaving farmland in Iowa was 666 million pounds. That was 14% more nitrogen than from 1980-1996, according to state data.

In Minnesota, state authorities found nitrogen in major rivers, including the Mississippi increased from 21% to 55% over the past 20 years, according to a summary report in 2020.

Silvia Secchi, a professor and natural resource economist at the University of Iowa, agreed. Government agencies “tell you they are spending all this money, therefore they must be doing something right. But if you look at water quality data, at what’s really happening, it’s getting worse, not better.

“We have a tremendous amount of nutrients that pollute all the waters here, and end up killing fish and damaging the environment downstream,” Secchi said.

‘Like a jigsaw puzzle’

There’s a reason federal and state agencies count so heavily on conservation practices to cure nutrient pollution. In field trials conducted by agricultural universities, and where farmers apply them over a period of years, they really work. The use of cover crops, which are planted not to be harvested but to provide a protective layer over soil, have been found to significantly reduce nutrient runoff. Planting vegetation in drainage ditches, installing sediment retention ponds, and building wetlands are also known to be effective.

Two of the largest conservation programs are the Conservation Stewardship Program (CSP) and the Environmental Quality Incentives Program (EQIP), both administered by the U.S. Department of Agriculture (USDA).

Last year, the USDA spent $400 million in CSP and EQIP payments in the six biggest Mississippi River Basin farm states – Illinois, Indiana, Iowa, Minnesota, Missouri, and Wisconsin. It’s a portion of the roughly $2 billion that the federal and state governments annually spend on conservation programs in the Mississippi Basin, according to Michael Happ, a researcher at the Minneapolis-based Institute of Agriculture and Trade Policy

But farmers in those six states – the basin’s largest source of nitrogen – applied CSP and EQIP practices to fewer than 3 million acres, according to federal data. That’s less than 3% of the 119 million acres of cropland in those states.

Sociologists who study why producers aren’t flocking to be paid to improve soil, conserve water, reduce runoff, and lower expenses, say the biggest impediments are the substantial changes required in how they farm. And their fear of losing productivity and revenue.

As a specialist with the Iowa Department of Agriculture who counsels farmers on best management practices, Porter explains it this way: “It’s perceived risk. Fear and worry about the effects on their drainage and their bottom line, and on yields. It’s a different system of farming than the one they’re using.”

Clark Porter, farmer and environmental specialist with the Iowa Department of Agriculture and Land Stewardship, prepares a nitrogen reducing buffer zone. (Photo by Keith Schneider/The New Lede)

Porter says his Iowa farm is an example of how effective changing farm practices can be in improving water quality. He started planting cover crops in 2011 on 550 acres to reduce erosion, build soil health, and keep excess nitrogen fertilizer in the ground. He constructed buffer zones in low-lying areas to prevent nitrogen from draining into streams. He retired 13 acres and raised a fertilizer-free meadow. The cost has been paid by state and federal grants.

As his diligence and techniques took hold over a decade, the farm’s soil fertility improved and the amount of fertilizer he spread diminished, as did the level of toxic nutrients leaving his land.  Samples of water draining from his farm showed nitrogen concentrations of 1 to 2 parts per million, equivalent to natural background levels.

“It’s a little like a jigsaw puzzle,” said Porter. “It’s a systemic solution with multiple layers of best management practices that you fit together based on your topography, your soil types. It’s all available. It can work.”

Porter is trying to convince other farmers in his state to follow in his footsteps. “I’m getting yields that I’m happy with. I’m not spending as much money on the front end,” he said. “I feel better about the effects on my neighbors and people downstream.”

‘Not like it is now’

One big reason many farmers have not been eager to embrace changes that lead to cleaner water is simply because they have not had to.

The federal Clean Water Act enacted in 1972 provided the EPA and states powerful authority to limit chemicals and contaminants from being discharged into U.S. waterways through a “point source,” defined as pipes and manmade ditches. The law does not consider flows from irrigated croplands or stormwater discharges as point sources.

At the time in the early 1970s, the implications of waiving oversight of farm pollution was not thoroughly evaluated. U.S. agriculture largely consisted of smaller, lower-polluting, mixed crop and livestock farms that grazed animals in manure-absorbing pastures.

But carving farms out of the Clean Water Act’s reach has since proved to be a significant factor in worsening water quality. Had the farm sector been held accountable for its waste, it would have been compelled to keep fertilizer and manure spread on fields out of surface and groundwater. That, in turn, would have kept farms operating at a scale that brought environmental costs in line with revenue.

Another barrier to any meaningful reduction in nutrient pollution is the action by Congress to incentivize farmers to plant corn, a crop that when conventionally grown requires large amounts of nitrogen fertilizer. U.S. farmers grow more corn each year than they can sell, driven by government incentives – a practice that enriches companies selling corn seed and the chemicals used to grow corn – but results in range of harmful environmental injuries, including fouling waterways.

“The scale of the problem dwarfs the level of response, unless you change the design of the dominant crop and livestock production systems,” said ISU’s Liebman.

When it was first identified in the 1950s, what scientists now call the Northern Gulf Hypoxia Zone was seen as a small biological curiosity. But in the 1980s, as researchers gained greater understanding of the peril to marine life, they started mapping the size of the toxic zone, documenting its ominous growth. Congress passed the Harmful Algal Bloom and Hypoxia Research and Control Act in 1998 to address pollution in U.S. coastal waters by pinpointing sources of nutrient contamination and their environmental consequences, and working to slash the pollution.

Now, more than two decades later, the money and time seems largely wasted, at least to Arnesen, who sees the deadly toll the toxic tide takes on marine life in her work operating a fishing boat.

“I started fishing offshore in the Northern Gulf of Mexico 25 years ago,” she said in an interview. “We caught everything. Not like it is now. Algae blooms cause massive fish kills. We’re seeing it all over the northern Gulf. It’s affecting the overall ecology of the system. It also affects me as a human being. We consume water out of the river. I try not to think about it. It scares me.”

This report was originally published by The New Lede and is part of an ongoing series looking at how agricultural policies are affecting human and environmental health.

Iowa Capital Dispatch is part of States Newsroom, a nonprofit news network supported by grants and a coalition of donors as a 501c(3) public charity. Iowa Capital Dispatch maintains editorial independence. Contact Editor Kathie Obradovich for questions: info@iowacapitaldispatch.com. Follow Iowa Capital Dispatch on Facebook and Twitter.

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