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<br />. <br /> <br />. <br /> <br />. <br /> <br />Discussion <br /> <br /> <br />Spring Creek stage varied by -0.4 feet over the study period, but these stage changes <br /> <br /> <br />nearly doubled the water depth, and reflected an order of magnitude change in flow from winter <br /> <br /> <br />baseflow to summer peak. The rating curve developed for this site is a linear relationship <br /> <br /> <br />because the channel is relatively deep with nearly vertical banks. The six flow measurements <br /> <br /> <br />cover a wide range of flows and measured stage can be used to approximate flow in the future. <br /> <br /> <br />Interestingly, the peak flow occurred long after on-site snowmelt, indicating a relatively long <br /> <br /> <br />response time of the hillslope aquifer to the snowmelt recharge. In addition, while there were <br /> <br /> <br />significant rains from mid-August into October, with several days receiving nearly one inch of <br /> <br /> <br />rain, yet there was no apparent response of the wells or Spring Creek stage to these events. This <br /> <br /> <br />suggests that these rains recharge the large hillslope aquifer, and the rain's effects are well <br /> <br /> <br />buffered. <br /> <br /> <br />Ground water levels were different for wells in the study area. Some wells, such as 5 and <br /> <br /> <br />10 had a seasonal water level change of more than two feet, while others such as well 3 had a <br /> <br /> <br />large annual change, but changed little during the summer. <br /> <br /> <br />At least two water sources supply the springs. The easterly and northern springs at wells <br /> <br /> <br />3 and 4 are alkaline, but have lower dissolved ion concentrations than water at well 2. However, <br /> <br /> <br />inflows near well 2 seem small in comparison to the flows near wells 3 and 4. Chemically, <br /> <br /> <br />Spring Creek water is similar to surface water discharging at springs near wells 3 and 4. <br /> <br /> <br />During the early summer of 2003 the most striking change in Spring Creek wetland water <br /> <br /> <br />levels was the large water table rise in the southern and northern sides of the wetland. In the fall <br /> <br /> <br />of2002 ground water flowed from the southern and northern sides of the wetland, but seepage <br /> <br /> <br />was near the base of the slopes. During early summer of2003, seepage was evident at elevations <br /> <br /> <br />higher than the highest wetland vegetation, and water tables in the wetlands were at the soil <br /> <br /> <br />surface, or water was sheet flowing across the soil surface. To maintain the wetland plants, <br /> <br /> <br />particularly Carex aquatilis, C. utriculata, C. nebraskensis, Mertensia ciliata and Senecio <br /> <br /> <br />triangularis, water levels must be at the soil surface for long periods of time during the summer. <br /> <br /> <br />Thus, ground water flows sufficient to maintain the water table of this spring must occur <br /> <br /> <br />regularly. In summer through fall of 2002, and early spring 2003, water levels at the upper sedge <br /> <br /> <br />zones were well below the soil surface, while by late June 2003 ground water levels had risen to <br /> <br /> <br />the soil surface. During this time, stream flow increased by 10 times. This suggests that the <br /> <br />I3 <br />