By Joyce Daniels
Michigan Sea Grant

When U-M professor Donald Scavia recently read the label on a container of organic lettuce, he was not surprised to find that the container itself was made from corn.

Scavia, one of several keynote speakers at the Graham Environmental Sustainability Institute Water, Health, + the Environment Conference held at the University of Michigan March 26 and 27, said that even before ethanol demands for corn became dominant, new markets for corn had been cropping up at every turn. Corn is used as a sweetener in practically everything we eat and drink, he noted, and is now used to make "eco-cups" and containers.

The problem, said Scavia, a professor in the U-M School of Natural Resources and Environment (SNRE) and director of the Michigan Sea Grant College Program, is that current policies that promote excessive corn production are having serious and long-term impacts on water quality.

"Corn is a primary driver of agriculture policy in the U.S.," said Scavia, and its growth requires vast amounts of synthetic fertilizer. "It's a particularly 'leaky crop.' Twenty percent of the nitrogen we add to our watersheds, often primarily from fertilizers, ends up leaching into our water systems."

The nitrogen flowing down rivers ends up in our oceans and Great Lakes, where the extra nutrients stimulate algae growth. When the algae die, the decomposition process depletes oxygen, creating hypoxic areas, or dead zones.

Scavia led a team of scientists who conducted an integrated assessment of the causes, consequences and correctives for the Gulf of Mexico dead zone in the 1990s. They concluded that agricultural runoff flowing down the Mississippi River was largely causing the lifeless area. A recent EPA Science Advisory Board review of that work and more recent research confirmed the earlier findings and calls for immediate action to reduce nutrient loads.

Closer to home, a dead zone in Lake Erie has recurred in recent years, and while its nutrient driver is phosphorus instead of nitrogen, agriculture is a primary source, and the dead zone has grown to the size it was in the 1970s.

A Fragmented Policy Framework

Backing up a step in the causal chain, Scavia attributed much of these water quality impacts on agricultural policy. He cited a major policy change in the 1970s, when agricultural loans were replaced by direct subsidies, which, he said, distorted markets and created a situation where corn prices fell and new markets had to be created.

"The move to production-based subsidies encouraged corn to be grown fence row to fence row in response to the í¢â‚¬Ëœget big or get out' policies promoted by the new approach," Scavia said. "Today, commodity subsidies in the key polluting areas of the Mississippi Basin overwhelm conservation subsidies by a 500 to 1 ratio."

Conservation subsidies would help farmers implement such practices as using natural buffer zones, wetland protection, and best management practices to reduce agricultural runoff. "With conservation practices," said Scavia, "we have the tools right now to reduce the size of dead zones."

But there's another problem: Energy policy. In particular, Scavia said, increased demands for ethanol, a corn-based biofuel, called for in the latest Federal energy policies would increase nitrogen and phosphorus inputs to our lakes and rivers-the exact opposite of what's needed to improve water quality.

Showing a map of proposal ethanol plants, with black dots covering the Midwest, Scavia noted, "If all the proposed ethanol plants are built, Iowa will have to import corn."

Scavia also discussed how trade in agricultural products contributes significantly to nutrient pollution and water consumption in the U.S. The continued expansion of corn production, along with water demands from ethanol refineries, said Scavia, will put additional stress on already overdrawn aquifers in drier parts of the country. Combined with impacts caused by a gradually warming climate, the challenge of maintaining an abundant, high quality supply of freshwater will become a human health issue in the U.S.

"All these policies are driving human health issues in ways that we don't really think about," said Scavia. For example, increased nitrates and other agricultural chemicals needed to satisfy the ethanol demand can contaminate groundwater supplies, while increased consumption of corn-based sweeteners contributes to the nation's obesity crisis.

In summary, he noted, there's no comprehensive policy protecting our nation's water resources. While the Clean Water Act, Safe Drinking Water Action, and Great Lakes Water Quality Agreement were all important steps, those policies are ineffective in addressing nonpoint source pollution, including agricultural and urban runoff, and are overwhelmed by counterproductive impacts of energy and trade policies and the lack of coherent Climate policies.

When asked how to best respond to the fragmented policy and "stovepipe solutions" that created this complex social and environmental landscape, Scavia said it's an uphill battle. But, he added, "I like to be positive. This conference and similar events are a step in the right direction."

Scavia is co-author of the book From the Corn Belt to the Gulf.

See: http://rff.org/rff/RFF_Press/CustomBookPages/Cornbelt.cfm.