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PrattTribune - Pratt, KS
  • Groundwater levels improve in parts of Kansas

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  • The groundwater level readings for 2013 were different than they have been in four years. The average groundwater level actually rose in central Kansas following years of drought but good moisture in 2013.
    Unfortunately, the western third of the state continues to show decreases in water table levels but the amount of lowering has shown decreases in the same time period.
    The further east in the state measurements are taken, the more likely the ground water table level will be higher.
    “It’s pretty incredible how quickly it increases as you move east,” said Brownie Wilson, Kansas Geological Survey water data manager.
    Wilson said that taking the average of all the wells in Pratt County revealed a change very close to zero. Some areas were up and some down so, on the average, Pratt County didn’t really move.
    The northern part of the county is showing rising levels while the center and southern part are down about a half a foot.
    While Pratt County as a whole has hardly changed, it only takes a short distance outside the county to see bigger increases. Just across the county line to the north in Stafford County, wells are registering increases of two feet.
    Other areas of GMD 5 have shown even more dramatic changes. On the eastern edge of GMD 5 some wells showed a rise in water table level of up to four or even five feet, Wilson said.
    The state sits on aquifers, large underground water areas that cover various parts of the state. The western third sits on the Ogallala Aquifer while Pratt and the surrounding counties sits on the Great Bend Prairie Aquifer.
    Most of the reason for the increase in water level was from higher than normal rainfall amounts in July and August where some areas got from 300 to 400 percent above the average rainfall in the area.
    In the Cheney Lake, the ponds had dried up and the lake was very low but the rains filled the farm ponds and recharged the lake to normal levels.
    A lot of Kansas still remains in drought conditions. While the rainfalls were not drought busters, they were a great boost to water table levels, Wilson said.
    The groundwater level varies across Kansas. In the south central part of the state, the water level is around 50 to 60 feet. That number really jumps in the western part of the state like in Haskell County where the water table level is 400 feet, Wilson said.
    The closer the water table is to the surface, the faster it can recharge from moisture.
    The Kansas Geological Survey and the Kansas Department of Agriculture Division of Water Resources record the water levels across the state.
    Page 2 of 2 - The state is divided into Groundwater Management Districts with Pratt County in GMD 5. Most of the observation is done through irrigation systems although some special wells are dedicated to just water level measurement.
    Some wells have built in sensors that automatically record water levels. In other wells where manual readings are done, a very simple system is used.
    A long steel tape measure is coated with blue chalk then lowered down into the well until it hits the water. The water washes away the chalk then the tape is brought to the surface and the distance between the washed off chalk and the top of the well is recorded. This way of measuring water levels has been used for some 60 years.
    Production wells, such as for irrigation, have to be measured in the manual fashion.
    The information goes into a database and gives the geological survey an accurate indication of water level change.
    Several factors impact the amount of change in the groundwater level. Precipitation is a key factor. If it doesn’t rain much, like in 2011 and 2012, most of the water levels will go down.
    Irrigation is also a key factor. The more irrigation demand on an aquifer, the more the level sinks. In some areas the amount of available water in the last ten years has dropped from thousands of gallons a minute to tens of gallons and some wells have gone dry.
    Irrigating corn takes the most water so some farmers have switched to wheat or milo that take much less water or have reduced the number of acres they irrigate.
    Watering livestock plays a factor in water table level as well.
    Soil type plays a big part in recharging the system. Sandy soil allows water to sink into the aquifer much faster then clay soils where water tends to run off rather than soak into the ground.
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