Educational Media Reviews Online

Major rivers have multiple meanings in all societies – as transportation arteries, as repositories for agricultural wastes and sewage, as sources of fish protein, as water sources, as cites for industrial activity, as recreational hubs, and, as in the case of Mark Twain, an inspiration for the creative muse. But no matter how mighty the Mississippi, it seems that there is simply not enough river to go around to satisfy all the demands that societies have placed on their waterways. And invariably industrial and agricultural uses seem to take precedence, creating rivers that are unrecognizable compared to less than a century ago and unfit for all the other ways a society might use them. This documentary recounts the disturbing transformations in the Mississippi River, which has fueled America’s economic greatness, its mighty heartland, but at crippling environmental and social costs.

Agri-business has perhaps had the greatest negative impact on the river. Farmers typically apply far more chemical fertilizer than the soy or corn can take up, just to make sure they receive optimum yields, but the result is that about half of the chemical fertilizers make their way into waterways as run-off. The massive run-off of phosphates and nitrates from chemical fertilizers into the river has produced dead-zones downstream – un-swimmable and un-drinkable water inhospitable to life, as the narrator so aptly puts it. Those chemical fertilizers originated in the arms business in World War I, as the foundation for powerful explosives. Afterwards chemists turned swords into plowshares, applying nitrogen to agriculture.

While farming practices have poisoned the waters, they have also resulted in the loss of precious topsoil every year, filling the river with sediment that constantly has to be dredged, at huge taxpayer expense. Soil – a non-renewable resource like oil -- is being lost at ten times the rate that it can be replenished, creating the conditions for another dustbowl. Mussels, the natural filters of fresh and salt water, are unable to endure the chemicals in the sediments introduced into waterways, triggering a more general die-off of the entire aquatic bio-system. The impacts are felt all the way to the Gulf of Mexico, where oxygen-starved waters have choked away the shrimp and as a result the livelihood of shrimp fishermen. Run-off of fertilizer makes its way into the water table and drinking water all along the Mississippi and in massive plumes visible from space into the Gulf. Algae feed on the plumes, die, and fall to the sea floor, where bacteria consume the dead algae and along with it oxygen in the water. The dead zone in the Gulf has doubled since 1985 and is now the size of the State of Massachusetts. Meanwhile, US agricultural subsidies encourage farmers to maximize crop yields, resulting in the production and use of even more chemical fertilizers.

Produced by the Bell Museum of Natural History at the University of Minnesota, the documentary relies on a number of experts to tease out the story of contamination, soil loss, and dead zones and their link to agro-industrial practices. Parallel to the scientific story the film investigates the social costs by interviewing the fishermen and others whose livelihoods have been slowly suffocated in the last two decades by the expanding dead zones. The result is to highlight an unintended consequence of America’s incredible agricultural productivity: the death of river and sea life in the Gulf and of the fishermen and women who depend upon it.

While noting the dire impact of overuse of chemical fertilizers, the film also highlights attempts to minimize their use: the use of natural fertilizer from local pig farms, for example, which has the added benefit of building up soil rather than promoting its loss; turning away from a mono-culture by converting some soil from cornfields into pasture for cattle, a practice that also lessens soil erosion; planting clover and other nitrogen-fixing plant cover on fallow fields to prevent erosion and fortify the soil. By highlighting environmentally-friendly practices – and urging the government to switch its subsidies to conservation rather than maximizing crop yields – the film points a way to a solution. The film, above all, highlights the paradox that science and technology are often assumed to provide people with greater control over their environment but they often do just the opposite – triggering unintended consequences that make the world a less rather than more livable place.