3 2 4 1 6 AQUIFER
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WATER CYCLE An aquifer is depleted primarily by u pumping for irrigation and v evapotranspiration from water, soil, and vegetation. The main sources of recharge are w precipitation, x runoff from heavy rains, and y excess irrigation water (as well as industrial wastewater and treated sewage). Rivers and streams z both discharge into the aquifer and carry water away from it, depending on local rainfall and the difference in elevation between riverbed and { water table, among other things. Soil composition is also important. Gravel and sand, being more porous, recharge more quickly. The soils atop the Ogallala are often clay and silt, so it recharges more slowly than some other aquifers. thirsty crops About 95 percent of the water pumped from the Ogallala is used for irrigation. Most of that water is fed into centerpivot irrigation systems, which made large-scale agriculture possible in the Plains. A more efficient technique called subsurface drip irrigation delivers water directly to the roots, greatly reducing waste.
Ogallala Ogallala Aquifer Aquifer Extreme Extreme to to Exceptional Exceptional Drought Drought Severe Severe Drought Drought
move ‘em out Drought has taken a heavy toll on cattle ranching, especially in Texas. Though recent rains have helped, grazing fields were too dry to support grasses over the summer, and the cost of commercial feed soared. Many farmers have been forced to sell off part of their herds.
Proposed Keystone XL Pipeline Keystone Pipeline Source: U.S. Drought Monitor, as of October 24, 2013
winter 2013/2014
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