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The obsenration wells can be subdivided into two types: those which lie within or �ery near the <br />South Platte River floodplain, and those located in tributary �aileys. The number of observation <br />wells in tributary �alfeys exceeds the number along the South Platte floodplain by '�?. <br />An evaluation of the data of beginning water le�els as compared to Spring 2Q02 le�els reveals <br />that approximately 59.5% of the wells have experienced a water le�el decline which compares to <br />a 58.2°/o decline in the 2001 report and 37.7°/o with declines in the 2��D report. By contrast, 6.3% <br />of the wells experienced a rise in the Spring 20�2 as compared to the Spring 1988 water level. <br />This percentage represents a#hird year of reduced number of rises including 10.1 % in 2001 and <br />15.9% in 200D. Declines of Spring 1988 to Spring 2002 range from -0.18� to -11.81 � as campared <br />to the range of -0.�8� to -8.05� in the 2001 repvrt. Declines on the order of 0.01 � are insignificant <br />in that such changes can be caused by wind, earth movement, and the effect of evapo- <br />transpiration and phreatic consumpiion or maybe errors in data recording. The table foflowing this <br />narrative entitled "Table of Vl/aier Le�el Trends of the South Platte Allu�ium through Spring 20�2" <br />recaps the statis#ics to date for this ongoing report in terms of all welfs within the tributary valleys <br />and the South Platte main stem/floodplain. <br />These data also reveal that the a�erages of the water level changes from Spring 1988 to Spring <br />20�2 wells within the tributary valleys (both rises and declines} are more than the averages of the <br />South Platte floodplain alluvium. By comparison, in 2001-2002 the average rise and declines of <br />Spring � 988 vis-a-��s Spr�ng 20D1 changes in the tributary valleys were, for the first time in three <br />years, more than those in the South Platte floodplain. <br />The average annual water level change for the period of record for this report is averaging -0.24 <br />ft/yr in the South Platte floodplains which is twice the annual rate eomputed last year. The <br />tributary vaileys experienced a nearly twenty-fold increase in a�erage annual decline at 0.80�/year. <br />Concurrently, the annual rise of the South Platte floodplain was kess in 20�2 than 2�01. ��erall, <br />the tributary valley rises were non-existent. <br />-2- <br />