A new tool could help in choosing the best ways to control pollution on even the smallest of waterways. The tool analyzes data from an area, and can compute the most cost-effective pollution-control strategies for water resources affected by agriculture in just a few hours - a process that currently takes weeks or months.

Indrajeet Chaubey, associate professor of Agricultural and Biological Engineering at Purdue University, combined a best management practices tool with a complex genetic algorithm that can search out the best solutions for non-point source pollution control in a watershed. Chaubey has spent the last several years developing a best management practices tool that takes into consideration all feasible solutions for decreasing non-point source pollution, or pollution that gets into water through runoff.

“When you have got limited resources to control non-point pollution in an area, you have to decide where to best use your resources," Chaubey said. “At the same time, you want to be sure you don't disrupt the agricultural production in an area."

The tool determines the best solution - such as changes in tillage practices, grass coverage, and structural changes on the land - based on the amount of pollution that can be eliminated, the economic impact to agricultural land, and other factors. The calculations used include soil, water, topography, and other data usually collected by governmental agencies. The algorithm assesses which of those practices will result in the most pollution control for the amount of money available with as little disruption to agriculture as possible.

“You have to look at the economic information at the same time. If the solution we provide will negatively impact farmers, it will not be adopted," Chaubey said. “Combining economic analysis with environmental analysis gives solutions that are more likely to be acceptable to farmers and watershed managers."

Current methods used to choose watershed-management practices include funding projects based on a first-come basis or spending on the project or projects seen as most beneficial. The problem is that one major project might break the budget, while several smaller projects could result in better pollution control for the same money.

Chaubey said the system was tested with information from the L'Anguille River Watershed in eastern Arkansas, and further testing is being done on six locations in Indiana. The research is funded by the U.S. Department of Agriculture.

(Purdue University)