Kansas Students Research Water Loss in Aquifer

Here’s the problem with one of the world’s largest aquifers, which supplies about 70 percent of the water in Kansas: Scientists don’t know much about it, like which parts of it lose water the quickest. The High Plains Aquifer, also called the Ogallala Aquifer, is a vast layer of underground rock and sediment that holds water. It stretches from South Dakota to Texas. Water levels in some parts of it, including western Kansas, have dropped as much as 200 feet since the aquifer was first tapped into in the 1940s. “Virtually every earth science student in the United States has been hearing for decades about the developing crisis in water supplies in the Ogallala Aquifer,” said Greg Ludvigson, an associate scientist with the Kansas Geological Survey, who has been hearing about it since his education in the 1970s. But now, recent technology and a $381,000 grant from the National Science Foundation has allowed the Survey to start working on answers. In the next few months, Survey scientists will be drilling in seven locations in southwestern Kansas to collect samples of the aquifer sediment. “We’re looking at it from step one, the bare basics of it,” said Jon Smith, assistant scientist at the Survey and principal investigator of the project. Smith said the project is designed to help scientists understand how the aquifer’s sediment is composed, how it holds water, and how different regions of the aquifer might be more or less productive. “That piece of the puzzle isn’t clear to us yet,” Smith said. “That layering, that architecture of the aquifer.” Scientists have studied the aquifer for a long time – Ludvigson said it’s a water source of strategic importance to the whole country – but the problem has been collecting a reliable sample that doesn’t fall apart. “You go to the beach and stick a coffee can into the sand. If you pull it up, all that sand falls out of the bottom,” Smith said. But now, the Survey will be able to capture foot-long, two-inch-wide samples from as much as 400 feet below the earth’s surface. Smith said the Kansas Survey was the only one in the Midwest with a rig capable of that, and it will be the first to gather these full samples from the High Plains Aquifer. It’s an “exploratory study to show what we’re capable of, right now,” Ludvigson said. The aquifer is vital to irrigation, the lifeblood of farming in western Kansas. Learning which parts of the aquifer are losing water quicker than others can help policy-makers, farmers, and city managers decide how to handle their water supply quicker. Someone down the line will have to make some decision about how much water can be drawn from a certain area, Smith said. “And right now, there’s really not a very good answer to that question.” Scientists will be able to build off the Survey’s research, take the same technology and drill other parts of the aquifer, and also apply the new knowledge to other aquifers around the world. Now, in the months before the project starts, Smith said the Survey has used the rig north of Wichita, drilling into the aquifer, to “run it through its paces and deal with the kinks.” ((26 OCT 2010))














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