Saving Water, One Field at a Time

NASA researchers have developed a computer program to help farmers better manage irrigation systems in real time. The software uses data from NASA satellites, local weather observations, and wireless sensor networks installed in agricultural fields to calculate water balance across a field and provide farmers with information on crop water needs and forecasts that can be accessed from computers or handheld devices.

Nearly 70 percent of the U.S. water supply is used for irrigation. Providing detailed information to farmers, says Rama Nemani, a senior research scientist at NASA Ames Research Center in Moffett Field, California, will help them make the most efficient use of the water available to them.

NASA is working with farmers and vineyard managers in the San Joaquin Valley in California to beta-test the new software as part of an 18-month research project to optimize irrigation management. The software is an advanced version of the Terrestrial Observation and Prediction System (TOPS), which NASA has used for many years to model such things as floods, droughts, and deforestation. The researchers developed software that can process satellite data from NASA and the U.S. Geological Survey and link it with wireless sensor networks’ measurements of ambient conditions like temperature, rainfall, and soil moisture. The system can also incorporate local weather observations and forecasts. The project is the first to combine satellite and surface observations to estimate irrigation needs at the scale of an individual field or vineyard, and distribute the information to farmers in near real time, says Forrest Melton, a project scientist at Ames.

The NASA project will look specifically at crop development over time to provide a complete picture and history of how crops grow. It will look at, for example, what kind of crops grow, when they reach optimal growth, and the density of crop canopies under different conditions. In addition, the project will summarize soil-water balance, estimate crops’ water use, and forecast irrigation demands. The information will be stored in a central database so farmers can compare past and current seasons and better manage their irrigation systems.

The challenge is to put the data into a readily understood form and deliver it efficiently to farmers, says Mehmet Can Vuran, assistant professor of computer science and engineering at the University of Nebraska-Lincoln. But the benefits are obvious. “Sensor data alone can improve irrigation efficiency by 20 to 25 percent, so with less water you can have the same yield,” says Vuran. He believes that the additional information will ultimately save enormous amounts of water.

The researchers plan to make the new data sets available to growers, farm managers, and irrigation consultants in the agriculture industry in early 2011, says Melton.