Web App Helps Prevent Soil Erosion

In hilly Missouri, farmers face the problem of soil erosion caused by water runoff. To combat this, they build terraces, an ancient agricultural solution that dates back to at least 4,000 B.C. However, designing terraces is a complicated and time-consuming process, and if done incorrectly can keep farmers from managing their land correctly.

But a new web-based application could bring the ancient tradition into the 21st Century, and reduce the amount of time it takes to design an optimal network of terraces. That could allow farmers to better manage their cropland, possibly meaning more food at the marketplace.

To build terraces, farmers in Missouri normally rely on aerial photos, topographic maps and a surveyor’s professional judgment. They then go to the Missouri branch of the U.S. Department of Agriculture Natural Resources Conservation Service (NRCS) to decide the layout and design of the terraces without cost, as the NRCS is paid by the government to do that. The process of designing a layout takes an entire day, and just one layout option is available. Next, the farmers hire a land improvement contractor, who has all of the necessary construction equipment to build the terraces according to the layout.

The size of each terrace varies per field, but the average field has six or seven terraces that are 1-1/2 to over 3 feet tall, each as long as the entire field and typically 120 to 180 feet apart. Construction costs $1.40 per foot. In 2008, Missouri farmers built 3.6 million feet of terraces and spent $8 million on construction.

If a terraces is not designed right a farmer cannot use the space for crops, leading to an overall lower yield.

The Web-based system reduces the chances that any terraces will be designed incorrectly and creates multiple layout options in a matter of hours. The software code for the program, called MOTERR for Missouri Terraces, was originally written in the early 1980s by a University of Missouri graduate student. Over the last three years, Allen Thompson, an associate professor at the university, reworked MOTERR, enhanced and expanded it, and then developed a Web-based interface for it. Allen believed that a web solution for the terraces could save Missouri farmers half a million dollars a year.

The program lets farmers input topographic information including total area, max elevation, location of ridgelines and waterways, and the system will make terrace layouts based on this information.

“It gives them a perspective they wouldn’t have otherwise,” he said. The app allows farmers to give input and opinions into the design, which they couldn’t do previously.

One of the major natural problems Thompson hopes to reduce with the help of the layout system is gully erosion. This type of erosion happens where water concentrates in a flow channel, producing excessive vertical soil cuts on a sloped surface. Thompson explained that the terrace system breaks up the slope length of the field, which routes water out of it and reduces the potential for gullies. It also improves water quality since it keeps sediments and pesticides in the terraced fields.

Members of the Missouri branch of the NRCS, which has given grants for this program’s development, have used and evaluated the system. Dick Purcell, the state engineer for the Missouri NRCS, said the layout system is one of the best he has seen in the Midwest.

“The challenge is taking expert skill and translating it into software,” Purcell said.

The system, which is currently in beta testing and only accessible to those designing, testing and updating it, will be available free to farmers in late 2011, will be free for farmers to use. The NRCS and local soil and water districts will train the farmers on how to use the system.