Conservation Drainage Systems Win Win for the Environment and the Agricultural Producer

Session 3B
4:10

Stephen W. Baker, Springfield Plastics, Inc.

Corrugated polyethylene drainage pipe has been used for agricultural drainage in the Midwestern United States for approximately forty years. This region is commonly referred to as the “bread basket” of the U.S. and boasts of some of the most fertile soils in the world. These soils respond favorably to drainage. During this same period the demand for agricultural crops has increased dramatically to “feed the world” and supply the increasing demands for bio-fuels. This response to drainage combined with this increase in demand has led to an ever increasing intensity of drainage over this time period. There also has been a significant increase in the use of fertilizers due to this increased demand.

An unintended consequence to the increase in drainage intensity and the increased use in fertilizers is an increase in nitrogen enriched discharges from agricultural drainage systems. These discharges have resulted in more costly treatment systems for drinking water supplies and have been linked to the Hypoxia zone in the Gulf of Mexico. Researchers, in response to this, have been developing and testing conservation drainage systems. These systems are being optimized for water quality benefits and crop production.

This paper will present results of research and demonstration projects in Illinois on two new types of conservation drainage systems. These systems are known as drainage water management systems and bioreactors. Both of these have been shown to reduce the nitrogen discharge from the drainage system. These systems have been around in Illinois for ten years and have been extensively studied the last five years. They show great promise due to their relatively low cost of nutrient removal and the fact that they both are in the field systems. The paper will also include a brief summary of the results of these systems in other areas of North America.