ST. LOUIS (AP) — The nation’s rivers and streams remain stubbornly polluted with nutrients that contaminate drinking water and feed a massive dead zone for aquatic life in the Gulf of Mexico, according to a newly released Environmental Protection Agency assessment.
It’s a difficult problem, concentrated in agricultural regions that flow into the Mississippi River. The agency found that more than half of the basin’s miles of rivers and streams are in poor condition for nitrogen and phosphorus from fertilizers flowing into waterways. For decades, federal and state officials have struggled to control farm runoff, the largest source of nutrient pollution that is often not federally regulated.
This problem is expected to become even harder to control as climate change produces more intense storms that dump rain on the Midwest and South. Heavy rains flood farmland, scooping up commercial fertilizers and washing them into nearby rivers.
“It’s really concerning that we’re clearly not meeting the goals we set for ourselves,” said Olivia Dorothy, director of river restoration for the conservation group American Rivers.
The assessment is based on samples collected in 2018 and 2019 and allows experts to compare river conditions in previous sampling rounds, although different sampling areas were used. It takes years for the agency to compile the results and release the report, the most comprehensive assessment of the nation’s river and stream health. While phosphorus levels dropped slightly, nitrogen levels remained almost exactly the same.
Nearly half of the river miles were found to be in poor condition for snails, worms, insects and other bottom-dwelling species, an important indicator of a river’s biological health. Based on species diversity, about a third were assessed as having poor conditions for fish.
“Controlling pollution is a big job. “This is a tough job,” said Tom Wall, EPA’s division manager for watershed restoration, assessment and protection. “Despite the enormous pressures on our waterways, things are not getting worse. And we want to see more progress.”
Water pollution from factories and industry is generally federally regulated. Wall said the Biden administration recently proposed tightening regulations for meat and poultry processing plants to reduce pollution.
When nutrient pollution flows into the Gulf of Mexico, it causes oxygen-consuming bacteria to grow. This creates a so-called “dead zone,” a large area ranging from the size of Rhode Island to the size of New Jersey where it is difficult or impossible for marine animals to survive, according to Nancy Rabalais, professor of oceanography and wetlands. Studying at Louisiana State University
This affects the productivity of commercial fisheries and marine life in general, but nutrient pollution also harms upstream. Too much nitrate in drinking water can affect the way the blood carries oxygen, causing human health problems such as headaches, nausea, and abdominal cramps. It can particularly affect babies and sometimes trigger “blue baby syndrome,” which causes the skin to take on a bluish tint.
EPA established the hypoxia task force in the late 1990s to reduce nutrient pollution and shrink the dead zone, but it relies on voluntary efforts to reduce farm runoff and has not significantly reduced the dead zone.
New regulations, not voluntary efforts, are needed, said Anne Schechinger, Midwest director of the Environmental Working Group. The Biden administration has done a lot to improve drinking water but not enough to reduce agricultural runoff, She said.
Methods to prevent runoff include creating buffers between farmland and waterways, creating new wetlands to filter pollutants, and applying less fertilizer.
This is an issue of political concern, especially in the large Midwestern agricultural states that contribute significantly to the problem. Many of these states cite voluntary conservation programs as evidence that they are addressing the problem, but new EPA data show little progress.
Minnesota is one of several states with so-called “buffer laws” that require vegetation to be planted along rivers, streams and public drainage ditches. But because groundwater and surface water are closely connected in much of the Upper Midwest, nutrient pollution can seep underground through agricultural fields and eventually bypass those buffers and still end up in streams, said Gregory Klinger of Olmsted County, Minnesota. soil and water conservation zone.
Focus should also be placed on preventing overfertilization; Brad Carlson, an extension educator at the University of Minnesota who communicates with farmers about nutrient pollution, said about 30% of farmers still use more than the recommended amount of fertilizer on their fields. problems.
Martin Larsen, a farmer and conservation technician in southeastern Minnesota, said he and other farmers are interested in practices that would reduce nutrient pollution. He broke up the typical corn and soybean rotation with oats and medium red clover; Secondly, it is a type of plant that can naturally increase the nitrogen level in the soil. For a corn crop following an alfalfa planting, he was able to get by with half as much fertilizer compared to a maize-maize rotation.
Growing oats and red clover as cover crops also improves the soil. But Larsen said it’s difficult for most farmers to plant them because they rely on immediate payback for everything they grow. According to 2017 data from the U.S. Department of Agriculture, only 5.1% of harvested farmland is planted with cover crops.
Larsen said more needs to be done to encourage better practices because the regulations are so unpopular. For example, he said, this could include companies changing the makeup of the feed they use for animals, giving farmers the opportunity to plant some crops that use less fertilizer. Or government programs that do more to subsidize things like cover crops.
He said many farmers in his community recognize the need to do things differently. “But at the same time, we feel trapped in the system,” he said.
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Walling reported from Chicago.
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Follow Melina Walling on X: @MelinaWalling.
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