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t <br />11 <br />W <br />U <br />_C <br />C <br />O <br />U <br />N <br />Q_ <br />Grand Island <br />— — 100 - Year Average Precipitation � Annual Precipitation <br />1980 1985 1990 1995 <br />Figure 5 <br />From 1980 through 1999, total precipitation at 11 stations in the Central Plate Valley <br />averaged 42 inches greater than normal. The smallest excess precipitation for the period <br />was 20 inches at Paxton, and the largest excess precipitation for the period was 67 inches <br />at Loup City. Several of the stations have received 10 percent or more above normal for <br />the past 19 years. <br />This unusually high precipitation and recharge to ground water over the last 20 years has <br />raised the water table well above levels that existed in the 1950s. High precipitation has <br />also produced generally higher river flows in the last few years. Seven out of the last ten <br />years have seen annual flows higher than the 1935 -99 median flows. <br />CROP CONSUMPTION <br />Vegetation consumes soil moisture, which influences the <br />amount of water added to the water table by rainfall. Evapotranspiration in <br />Evapotranspiration is the amount of water that plants the flood plains <br />consume and that evaporates from the soil surface. This normally does not <br />water is removed from the root zone and does not enter the lower the water table <br />ground water. Plants draw moisture from the plant root enough to cause a <br />zone, which typically is 2 to 6 feet in depth. The root zone loss from the river to <br />may be replenished by irrigation or by precipitation. The ground water. <br />sandy soils in the Platte River Valley can hold 1 to 2 inches <br />of readily available water per foot of soil (the water holding <br />capacity). When the water holding capacity is exceeded, the surplus water percolates to <br />the water table. <br />Ground Water and River Flow Analyses <br />