Coal Creek (CC) is a high-elevation, headwater tributary to the Upper Colorado Basin located in the Ruby-Anthracite Range in the central Colorado Rocky Mountains. The CC watershed is 53 km2 in area and ranges in elevation from 2712 to 3668 meters. CC originates near Lake Irwin and enters the Slate River near the town of Crested Butte before joining East River and eventually the Gunnison River. The watershed is seasonally snow-covered from November through June. The average temperature is 0.9˚C and it receives around 670 mm of precipitation each year, about 66% of which falls as snow (Carroll et al, 2018). The remaining precipitation falls during the summer monsoon season (July through September). Although monsoon rains comprise nearly 40% of the annual precipitation, they contribute minimally to the streamflow because the moisture is taken up by vegetation and lost via evapotranspiration (Carroll et al, 2020). Vegetation in the basin is strongly aspect driven, with north facing aspects dominated by evergreen forest (65%) and south facing aspects dominated by deciduous (9%) and herbaceous (20%) vegetation. High elevation ridges are barren (3%) (Zhi et al, 2019). Discharge in CC is dominated by snowmelt, with average peak flow occurring in June in response to snowmelt. Flows recede throughout the summer and fall, with small peaks in flow due to monsoon events. CC reaches baseflow conditions by early September and they persist throughout the winter until the onset of snowmelt in April. The lower CC watershed is underlain predominately by sandstone (Mesaverde Formation) with glacial till deposits occurring near the streambed. The upper portion of the watershed is underlain by mafic intrusive plutonic rock, emplaced during the Middle Tertiary. Areas of the upper north slope of the watershed are underlain by mudstone (Wasatch Formation).