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<br />Introduction <br /> <br />In Colorado many aquatic and wetland ecosystems are supported by ground water flow, <br />including fens, wet meadows, spring complexes and some small streams. Spring complexes are <br />critical habitat for many species of native wildlife and plants as well as domestic livestock. A <br />spring forms where a ground water flow system reaches the soil surface producing a seasonal or <br />perennial discharge. In a few areas ground water discharge may be so strong that a stream <br />forms. In all cases, shallow or deep ground water discharging from unconsolidated alluvium, <br />colluvium, dunes or bedrock provides the driving hydrologic force creating the ground water <br />discharge and supporting the biota of springs. <br />I studied the Spring Creek site, located in the Ragged Mountains in the West Elk Range <br />of the Grand Mesa, Uncompahgre and Grand Mesa National Forest in westem Colorado to <br />analyze the interaction between ground water levels and spring flow. Snowmelt and rain runoff <br />from the Ragged Mountains percolate a massive landslide debris deposit forming a westward <br />flowing colluvial/alluvial ground water flow system. These waters appear to be perched on the <br />Mancos Shale, which is westward dipping in this area. The shale provides a relatively <br />impermeable boundary upon which ground water flow occurs. This flow has lubricated the <br />contact between bedrock and unconsolidated material, allowing landslides to occur. The Spring <br />Creek site occurs where the contact between shale and the unconsolidated material is exposed <br />and water flowing on the shale surface discharges forming the spring complex and supporting <br />Spring Creek. The water flowing through and across the shale accumulates and transports salts <br />and produces alkaline waters. Wetland communities often occur at springs, and at the Spring <br />Creek site a diverse set of communities occUr. Preserving the ecological integrity of the spring <br />complex includes protection of wetland communities at Spring Creek that occur where water <br />discharges from the hillslope. <br />This report presents field data collected at the Spring Creek study site during the fall of <br />2002, winter of 2002-2003, and spring through fall of2003. The goal of this investigation was <br />to determine 1) the natural range of variability in groundwater levels in the study area, 2) <br />develop an understanding of the linkages between surface water and ground water, 3) develop <br />recommendations for hydrologic criteria that could be used to protect plant and aquatic <br />communities, and the ecological functioning of the spring and its ecosystem. <br /> <br />1 <br /> <br />. <br /> <br />. <br /> <br />. <br />