This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American
If you were to stand at the southwestern-most tip of New York State and pour a glass of milk into the nearest waterway that liquid would eventually flow all the way to New Orleans. Along their way those milky molecules would pass through Cairo, Illinois mixing with raindrops from northwestern Montana at the confluence of the Ohio and Mississippi Rivers before heading down to the Gulf of Mexico.
This gives you an idea of the expansive triangle-shaped Mississippi watershed; a watershed that happens to house some of the most intensely farmed land on earth. All told, the Mississippi-Atchafalaya River Basin or MARB touches 31 states. The land area of the MARB is a whopping 41% of the contiguous United States.
Each summer, after the famers of the American Midwest spread manure or spray anhydrous ammonia over their emerging crops, summer rains (usually) come and carry much of that fertilizer down a massive web of tributaries into the mighty Mississippi River. The annual spike in nutrient (mostly nitrogen, phosphorous, and potassium - NPK) causes massive algal blooms. As the algae decompose bacteria feast on the detritus only to die when there is no more food taking with them dissolved oxygen. The resultant area of low oxygen or hypoxia is eerily named the “Dead Zone.” This is a slight misnomer as the area is not completely dead although the lower oxygen levels do threaten large portions of the aquatic food web. In addition to oxygen deprivation a small percentage of the blooming algae also produce lethal toxins to fish, birds, and mammals. The size of the Dead Zone varies summer to summer from about the size of Delaware to New Hampshire depending on the amount of rainfall.
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Four years ago I wrote a blog-post explaining this expanding problem in the Gulf of Mexico and two US Government mandates pulling the Dead Zone in opposite directions.
In 2008 the Environmental Protection Agency (EPA) set up an Action Plan to reduce the size of the Gulf's Dead Zone. However, this goal stood in opposition to the Energy Independence and Security Act of 2007 (EISA), which requires the production of 36 billion gallons of biofuels by 2022. In recent years most of that “biofuel” has taken the form of corn-ethanol. Some have estimated that up to 40% of the US corn crop has been converted to ethanol, though this calculation may be an over-estimate as it does not take into account what happens to the corn kernels after the soluble sugars have been extracted. Nonetheless, the implementation of EISA has jump-started US ethanol production since 2008. The United States is now the world leader in ethanol production outpacing Brazilian cane-sugar ethanol by a factor of two. All this corn grown for ethanol has meant much more fertilizer spread on the farm fields of America and that much more nutrient flowing into Dead Zones all over the coasts, especially the Gulf of Mexico.
I wanted to follow up on my initial story and see what is going on with EISA and its effect on the Dead Zone today.
Has the Dead Zone shrunk or expanded? Are the opposed mandates still in place? Who is in charge of managing the Dead Zone in the Gulf and the contributing factors like fertilizer run-off?
Shrinking or growing?
It varies. The American Midwest experienced two straight years of drought in 2011 and 2012. Less rain meant less nutrient run-off. Though the Dead Zone was smaller than predicted by the National Oceanic and Atmospheric Administration (NOAA) in 2012, the increased rains throughout the Mississippi watershed in 2013 resulted in a Dead Zone twice as big as last year’s. Fertilizer accumulated during the drought was released with vengeance during the heavy summer rainfall this year. I am curious to see if the horrific flooding we’ve seen recently in Colorado will have any latent effect on the Gulf’s Dead Zone this fall.
What about the mandates?
As far as I can tell the opposing mandates - EISA and the EPA-backed Gulf Hypoxia Action Plan - are still at loggerheads. Though there was a recent slash to the proportion of cellulosic ethanol required to be blended in US gasoline in 2013 the overall goal of 36 billion gallons of biofuel by 2022 remains in place. Both environmentalists AND the oil companies have sued the EPA for not clearly regulating nutrient runoff and forcing companies to conform to the Renewable Fuel Standard respectively.
It seems EISA is not going anywhere fast and with good reason. It has been argued that the implementation of EISA has reduced America’s dependence on foreign oil by 20 percent, supports 400,000 jobs, reduces greenhouse gas emissions by at least 34 percent, saves the average motorist $1,200 per year, and adds $43 billion to gross domestic product.
Say what you want about economics of ethanol as fuel but it is hard to argue these results.
If agriculture is going to keep escalating in order to meet world food demand AND keep up with the EISA mandate how can we hope to reign in the Dead Zone?
Nine environmental groups including the Natural Resources Defense Council, the Gulf Restoration Network, the Sierra Club and the Prairie Rivers Network have come together to force the EPA to set up run-off ground-rules. In a ruling handed down Friday September 20th, 2013, U.S. District Judge Jay Zainey in New Orleans gave the EPA six months to decide whether to set standards for nitrogen and phosphorous in U.S. waterways. If the EPA says no the judge has stipulated that they at least have to explain why such regulation is not needed.
As an environmentalist, it makes me happy to see steps taken to construct a framework for regulation of non-point source pollution like fertilizer run-off but I am struggling to see how the EPA will go about telling farmers to use less fertilizer when they detect too much in the rivers. In any case the EPA has a six months window to figure out how to manage this complex problem.
Dead Zone Judo.
While working on this post an idea occurred to me. A sub-section of EISA requires money be spent on algae-based biofuel research and development. Keeping in mind that the main precursor to the Gulf Dead Zone a gigantic algal bloom, I thought, “why not develop technology to harvest the algae in the Dead Zone itself and use it to extract biofuel?” This takes the source of the problem and turns it into a solution. A quick Google search made me realize I am not the first person to think of this idea. There are companies and universities trying to capture bio-fuels from algal blooms around the country. However, attempts have been met with skepticism. The concern is that the variability and seasonal nature of Dead Zones would make scaling-up harvesting efforts less than economically feasible. But still, the vision of a fleet of mobile bio-rectors seeded with genetically enhanced high-oil producing algae getting dropped smack in the middle of a would-be Dead Zone seems really cool to me. While we wait for the EPA to decide how, or if, it will try to regulate nutrient run-off why not try to figure out how to turn the Dead Zones of the world into floating biofuel farms?