Many if not most farmers will loudly deny that assertion, though many if not most wouldn’t allow tile outlets to be sampled in June, either.
Here is what convinced me I own the Dead Zone. First, our shallow (26') bored well was part of an Illinois Water Survey study in 1992 to measure nitrates and pesticides. Samples taken in January and June, found no detectible pesticide residues, even though chemicals had been applied less than 15' from the well. The N sample returned at 0.44 mg per liter in January and 4.5 mg per liter in June, both below the allowable limit of 10 mg per liter. Yet a tenfold increase had occurred. (Our well is uphill, far from septic field or towns.)
Second, mounting regional research confirms my culpability. To quote from the 2013 Iowa Nutrient Reduction Strategy: "Nonpoint sources account for 92% of the total N inputs and 80% of the total P entering Iowa streams annually." In other words, wastewater treatment plants (sewage and industry) add just 8% of total nutrients. Even allowing generously for natural N and P levels, nonfarm contributions and atmospheric contributions, hydrologists have no trouble pointing the finger at farm runoff. The U.S. Geological Survey concurs, putting the ag contribution at 70%.
The clincher is drought years, when farm streams dry up and nutrient levels fall. During the drought year of 2012, for example, the Zone was the fourth smallest on record, even though nonfarm sources discharged about the same volume of nutrients.
Alternatives to Fault-Finding. It is not in our DNA to admit we are at fault. It’s pretty rare in any industry. So we are left with few other responses:
"Farmers must decide whether to own the dead zone in the gulf caused by nutrient runoff or choose from among blame-shifting replies."
- Dismiss the problem. The idea of knowingly wiping out life in several thousand square miles of ocean is repugnant, but commercial losses to fishing are arguably less than Midwest crop values. To write it off as a cost of business would take self-serving chutzpah but is a familiar tactic.
- Deny guilt despite overwhelming evidence. Such motivated reasoning has proven remarkably popular and effective for other issues.
- Dispute the evidence. Study it to death. Accuse all authority—academia, government, industry, NGOs—of being ideologically motivated. Deploy in-house research to refute condemning data.
- Make it an ideological issue. It’s not about dead plankton in the Gulf; it’s about private property or scriptural admonition or how Founding Fathers would have handled hypoxia.
- Kill the umpire. Mount a crusade against the Environmental Protection Agency, which is required by law to remediate the problem. If pressed, insist we be paid to not pollute, essentially extortion.
- All of the above.
Great credit should go to efforts such as the Iowa Nutrient Reduction Strategy, but I am uneasy about our industry even acknowledging the scope of the problem, let alone shouldering responsibility for a solution. As the Center for Agricultural and Rural Development concluded, "a major change in the landscape will be needed [including] new practices and new crops." The Twitter version: less corn.
One researcher has equated the effort needed to reduce nutrient loading to putting a man on the moon. I wish I could see that commitment even beginning to form. Maybe it will, but I suspect only as a last resort.
- Iowa Nutrient Reduction Strategy (PDF)
- USDA--Natural Resources Conservation Service (NRCS) Nutrient Management Tools
- USGS Circular 1350: Nutrients in the Nation's Streams and Groundwater
- Des Moines struggling to clean nitrates from drinking water blamed on farming, might sue state
- What Is Farm Runoff Doing To The Water? Scientists Wade In
- Solution to Pollution: It Starts on the Farm (PDF via The Iowa Policy Project)
- Can Voluntary Adoption of Agricultural Practices Achieve the Hypoxic Zone Reduction Goals? (via Iowa State University's Center for Agricultural Policy and Rural Development)