A soil conservationist's view of ethanol

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This article first appeared in INHF's Fall 2006 magazine.

by Duane Sand

Cathy Engstrom/INHF

By some calculations, producing one gallon of ethanol is preceded by 20 pounds of soil erosion—which depletes Iowa’s land and pollutes our water. If ethanol is to be a truly renewable fuel, its production must be tied to improved soil conservation.

I have been a proud user of ethanol blend gasoline for many years. I believe renewable fuels are needed to reduce oil dependence, build Iowa’s economy and reduce greenhouse gases that cause global warming. However, ethanol can’t be considered a renewable fuel if its production essentially “mines” precious topsoil from highly erodible slopes.

Little is said about the soil erosion associated with the corn crop that feeds ethanol. According to the USDA National Resources Inventory, water erodes an average of 4.9 tons of topsoil per acre annually from Iowa’s cultivated cropland. When I divide that soil loss by the average corn yield (173 bushels estimated for 2006) and then by 2.7 gallons of ethanol produced per bushel, I find a ratio of 20 pounds of soil washed away per gallon of ethanol produced.

In other words, Iowa’s imminent 2 billion gallon per year ethanol processing capacity is likely associated with over 20 million tons of soil erosion—our free ride paid by future generations. To make ethanol a truly renewable fuel, we must heavily invest in helping farmers improve soil conservation. Crop-based fuels are renewable only when every farmer’s conservation plan shows enough practices are being used to sustain soil productivity.

To get there, we must educate ethanol’s consumers, producers and policy-makers of the need to more than double the conservation investment in Iowa. This is a big request, but it is doable:

• Congress will save billions of dollars in commodity subsidy payments if ethanol raises grain prices as projected. Those savings could easily restore the budget cuts that have prevented Conservation Security Program rewards for all active conservation farmers.
  
  
• At the state level, our legislature generously offers more tax subsidies to gas stations for selling ethanol than it spends on soil conservation incentives for farmers.
  
  
• The state general fund is growing, partly because of the biofuels industry, and much more of that money is needed to protect the natural resources supplying that industry.
  
  
• It is also appropriate to redirect some of Iowa’s motor vehicle use tax and the environmental protection charge on motor fuels so drivers help abate their environmental impacts.
  

Iowa farmers have made steady progress in conserving soil over the last 20 years, and government can now afford to help them do even better. It is time to make greater soil and water conservation investments to pursue a truly renewable energy policy.

Duane Sand is a member of the State Soil Conservation Committee and is a public policy consultant to INHF.

For more information, e-mail Cathy Engstrom, Director of Communications, or call (515) 288-1846.