Landsat plays key role in water-use maps

US Geological Survey: Data from earth-observing Landsat satellites plays a central role in a new, award-winning type of mapping that tracks water use. Water-use maps help save taxpayer money by increasing the accuracy and effectiveness of public decisions involving water – for instance, in monitoring compliance with legal water rights. The maps are especially important in dry western states where irrigated agriculture accounts for about 85 percent of all water consumption.

Using Landsat imagery supplied by the U.S. Geological Survey in combination with ground-based water data, the Idaho Department of Water Resources and the University of Idaho developed a novel method to create water-use maps that are accurate to the scale of individual fields. The Ash Institute at Harvard University recently cited Idaho’s original design for these maps as an outstanding innovation in American government.

“The USGS Landsat archive, dating back to1972, has proven to be a versatile source of consistent data about land surface conditions,” said Bryant Cramer, USGS Associate Director for Geography. “This advance by the Idaho water monitoring team is both brilliant and practical. Looking forward, it’s indicative of what researchers in many countries can accomplish with the data.”

…As agricultural irrigation needs and swelling city populations amplify demand for scarce water supplies, water management strategy has been forced to shift from increasing water supply to more effectively managing water use at sustainable levels. Thus, accurate water-use mapping is critical. The Landsat-based method can be as much as 80 percent more accurate than traditional measurement methods….

Landsat image of irrigation in the Sahara Desert. No idea whether this is related to the topic of this story, but this looks like a painting by Klee