Four boreholes (MW1, MW1UZ, MW2, MW2.1) were drilled in the fall of 2017 and summer of 2018 in upper Redwell Basin, a headwater catchment underlain by hydrothermally altered sedimentary rock in the Elk Mountains near the town of Crested Butte, Colorado. The boreholes were continuously cored using a wireline HQ-sized coring system and sample a combination of Quaternary-aged surficial colluvium and the Cretaceous-aged Mesaverde Formation. In-situ injection-based hydraulic tests were performed in MW1 and MW2 during drilling while advancing using a single-packer apparatus in tandem with an in-line flow meter and interval pressure monitoring. Borehole geophysical logging was performed in MW1, MW1UZ, and MW2.1 in the open holes. The boreholes were completed as vertically discrete nested monitoring wells. Pressure transducers have been deployed in selected wells to monitor groundwater level and fluid temperature over time. This data release includes borehole location and well completion information as well as related hydrologic and geophysical data. The borehole geophysical data directory contains borehole geophysical logs. The hydraulic test data directory contains in-situ packer test data and laboratory permeability/porosity results from selected core samples. The hydrologic monitoring data directory contains groundwater level and temperature data for selected wells.