Iowa has 31 million acres in farmland, with 23 million of that planted to corn and soybeans, Northey said. Nine million acres of land is drained by tiles, underground drains that efficiently remove water from fields.
These drains also mainline nitrogen directly to streams. Underground nitrogen is “the most critical conservation concern” in the Upper Mississippi River Basin, said a 2010 USDA study of conservation practices.
Artificial wetlands can help get the nitrogen out. With the help of a federal conservation program, Iowa has built 70 shallow wetlands to filter tile-line water. “We’re seeing a 40 to 70 percent reduction in the amount of nitrogen coming out,” Northey said. “It’s pretty dramatic.”
The artificial wetlands are expensive, and they don’t work on every property. “We’re building five to 10 a year,” said Northey, a member of the federal-state hypoxia task force. “It would take building hundreds of years to get all of that.”
Scavia, with the University of Michigan, said significant changes are needed to shrink the dead zone – and quickly. The dead zone appears to be reaching a “tipping point” where the system is becoming increasingly sensitive to nutrient inputs, he said, and climate change exacerbates the problem as it warms water and increases intense storms.
Scavia’s solution? Fix the federal “farm bill,” which determines agriculture policy and subsidies. “It’s that difficult, and that simple,” he said. “It’s how much we incentivize producers. I believe farmers understand and do want to protect the environment.”
Voluntary methods are all well and good, said Rota, of the Gulf Restoration Network, but he wants to see enforceable standards as well. His group and others recently filed a lawsuit asking the EPA to set national criteria for nitrogen and phosphorus runoff. “We need that minimum bar to start making progress,” he said, “because so far, we’ve only seen the dead zone trending bigger.”
The EPA has so far refused to set national criteria, saying the best approach is to work with states to develop their own standards and cleanup plans.
For his part, Northey said the first step is education. Through the task force, he has taken Iowa farmers down to the Gulf and brought people from Mississippi back up to see what Iowa farmers are doing.
The rivers forever link farmers in the Midwest and fishers in the Gulf.
“Maybe it doesn’t seem like it when you’re working on your farm on a cold November morning, but we are tied to those folks,” Northey said. “We are tied, up and down the river, all together.”
This article originally ran at Environmental Health News, a news source published by Environmental Health Sciences, a nonprofit media company.
See what we're tweeting about
8 Comments
Add CommentWhat is needed to get a clearer picture of the problem and its sources is to be able to deploy a large number of remote sensing devices that can monitor the water at many locations without having to send samples to a lab. This would give a better indication as to the principle entry points of the nitrates into the rivers and allow a more responsive methodology for characterizing and controlling the situation.
Reply | Report Abuse | Link to thisAs more data is collected, additional sensors can be deployed to narrow the search for the sources. Once sources are identified, they can controlled using either a nitrate tax to make it too expensive to continue allowing nitrates to enter the system or some other sort of incentive to fix the problem locally.
I am sure that there is room for research in ways to break the nitrates down before they reach the gulf as well. Perhaps systems located at the various dams along the way to process the water as it goes through. It would have to be pretty massive to be able to treat the volumes of water flowing through but perhaps it could be distributed more easily along the streams flowing into the rivers instead.
We do live in a world where everything is interconnected and where the miracle cure for one can be the eternal curse for another. We need to remember that we all need to share this planet and live more harmoniously with it.
I can't believe our rivers and the Gulf are being polluted by those evil, rotten, money-mongering oil companies...oh...wait...I mean, farmers.
Reply | Report Abuse | Link to thisThe world is becoming scarier than ever.
Reply | Report Abuse | Link to thisLittle progress is being made because global resources are being diverted combating a non-pollutant (CO2). The real significant pollutants are losing out of the trillions invested globally, with no resultant effect.
Reply | Report Abuse | Link to thisWe need to re-focus our attention (and money) to real solvable pollution problems. GK
"Little progress is being made because global resources are being diverted combating a non-pollutant (CO2)."
Reply | Report Abuse | Link to thisDenial is a mental disease far more debilitating then liberalism. In the end it results in a terminal disease.
Nitrogen increases cause phytoplankton to multiply, but this should increase nutrients for species in the food chain that consume the plankton. As the dead zone grows, so should the abundance of sea food as the oxygen further out returns to the balance nature established. This is not the case as evidenced by increasingly smaller catches in the gulf. Unfortunately there is other pollutants at work that are destroying the food chain farther out. Pesticides (which are made from petrochemicals) and crude oil which has been purposely sunk to the floor of the gulf (does anyone remember or care who NALCO was or how much they spent on lobbying during the worlds worst oil spill?)is suddenly and suspiciously not investigated or even suspect according to this article. The excuse is just that scientists don't understand it all. Apparently no one is getting paid enough to put the blame where it belongs. It is far more convenient to blame individuals that fertilize their lawns and farmers growing corn for ethanol.
Everything has a cause and effect and it should be a no-brainer to look at the total picture, but Americans have been so dumbed down by the mainstream media which is funded by big business (not liberal environmentalists as claimed by those responsible) that the obvious now becomes the ridiculous as evidenced by G. Karst's post above.
CO2 is as much a part of the problem as the rest of the oil and coal industry's pollutants. CO2 increases the acidity of the water and raises the water temperature which both benefit algae and ultimately plankton production and destroys coral which lives on live plankton, not dead decaying plankton and the poisonous bacteria it creates.
It is hardly a misunderstood problem. It is just another case of active denial by the very people and industries that are creating the problem in the first place.
What humans need to do is weigh the beneficial and non-beneficial attributes and choose solutions based on logic not greed.
Nitrogen fertilizer is depleting oxygen the dead zone of the Gulf. Why not pump air to the bottom of the gulf like is done in fish tanks? Why not pay for the operation by a tax on nitrogen fertilizer? Let the polluters pay for the consequences of their pollution.
Reply | Report Abuse | Link to thisIn my opinion, the hidden factor here is depletion of the soil in terms of buried carbon. i.e the nitrogen is not being retained as well by the soil because it is becoming more and more just a 'dry hydroponics' sterile medium.
Reply | Report Abuse | Link to thisWe need to make better soil by getting away from the idea that agriculture is about adding nutrients to a dead inorganic media designed only to stabilize the root system.
Move towards ways of allowing more nutrients from fertilizer to be retained, such as biochar, burying stalks, low tillage, etc. Maybe even letting fields lie fallow and alternating to give bacterial and worms time to establish themselves between crops. Investigate multiple crops in the same field (I know it makes harvesting more complicated but nutrients may be taken up faster. We need to develop actual soil as it is MUCH more resistant to losing nutrients than the basic minerals.
Looking over the responses, I despair of the public seeing agriculture as a biological process. They seem to regard it as an industrial one.
Of course doing the common sense thing and completely eliminating the levees south of New Orleans is just not considered of course.
Reply | Report Abuse | Link to thisIf this was done the waters of the Mississippi would then be filtered by the remaining marshlands that CAN utilize those excess nutrients and regrow themselves.
Destruction of these levees doesn't have to entail destroying communities if done right, but like I said since it's not even considered as an option proper planning has never been done. How pathetic.