Data

Near-surface geophysical surveys were completed in September 2020 in a mine-affected drainage near Breckenridge, Colorado, known as French Gulch. The study area was along a 0.3 mile (0.5 kilometer [km]) reach of French Gulch, approximately 2 river miles upstream from its confluence with the Blue River. This data release presents data from three geophysical surveys that used fiber-optic distributed

The U.S. Geological Survey (USGS), in cooperation with the Grand Valley Drainage District and the Colorado Water Conservation Board, conducted a loading analysis for selected constituents and tributaries to the Colorado River in the Grand Valley, western Colorado, using data from 1991 to 2018, to characterize concentrations, stream loading, and load reductions for Escherichia coli, total recoverab

Geospatial datasets were developed to estimate the altitude of the top of bedrock, altitude of the top of the Paradox salt, altitude of the water table in the alluvial aquifer, and the thickness and extent of saturated alluvium in the Paradox Valley in western Colorado. This study was completed by the U.S. Geological Survey (USGS) in cooperation with the Bureau of Reclamation for modeling of brine

The American Tunnel, the Black Hawk mine, the Gold King mine, the Mogul mine, and the Red and Bonita mine are located in the Cement Creek watershed, tributary to the upper Animas River near Silverton, Colorado. All five sites have tunnels that drain groundwater from abandoned underground mine workings to the surface. This draining water has elevated concentrations of metals and degrades water qual

In 2004, the U.S. Geological Survey initiated a large-scale regional study of the Denver Basin aquifer system to evaluate the hydrologic effects of continued pumping and document an updated groundwater-flow model useful for appraisal of hydrologic conditions (Paschke, 2011). This data release includes spatial datasets used as input for a three-dimensional groundwater-flow model of the Denver Basin

Near-surface geophysical surveys were conducted during March 2018 in an irrigated agricultural drainage near Delta, Colorado, locally know as Sunflower Drain. This data release presents results of two surveys, one using fiber-optic distributed temperature sensing (FO-DTS) and the second using a horizontal-to-vertical spectral ratio (HVSR) passive seismic method. For the FO-DTS, a temperature sensi

Native trout in the West suffer a high degree of vulnerability, as highlighted by cutthroat trout, a group of 14 subspecies, most of which have been petitioned for listing under the Endangered Species Act (ESA). In the Southern Rocky Mountains, greenback cutthroat trout (Oncorhynchus clarkii stomias; GBCT) are listed as threatened under the ESA, and few populations remain, in part because of the i

The U.S. Geological Survey (USGS) is actively investigating the use of innovative remote-sensing techniques to estimate surface velocity and discharge of rivers in ungaged basins and river reaches that lack the infrastructure to install conventional streamgaging equipment. By coupling discharge algorithms and sensors capable of measuring surface velocity, streamgage networks can be established in

This dataset contains cross-section geometry and sediment-size data collected in the fall of 2019 from Muddy Creek and North Fork Gunnison River below Paonia Reservoir, western Colorado. Six cross sections were surveyed using Real-Time Kinematic Global Navigation Satellite System (RTK-GNSS) methods to document channel geometry below Paonia Reservoir. One cross section was surveyed on Muddy Creek b

The phenylpyrazole insecticide fipronil and its degradates are a potential surface-water contaminant and toxicant to nontarget species such as aquatic macroinvertebrates. To better understand how fipronil, fipronil sulfide, fipronil sulfone, desulfinyl fipronil, and fipronil amide affect aquatic communities, a 30-day mesocosm experiment was run. Rock trays were colonized with natural benthic commu

In 2019, the U.S. Geological Survey, in cooperation with the Upper Colorado River Wild and Scenic Stakeholder Group, studied the magnitude and frequency of streamflow needed to initiate bedload transport of gravel-sized and finer sediment on the Colorado River to maintain spawning habitat for fish and maintain substrate and interstitial spaces for benthic macroinvertebrates. Bedload transport occu

Dataset includes the analysis results of 49 inorganic chemical elements bound to suspended-sediment particles below Paonia Reservoir during a sediment release in September 2017. Suspended-sediment samples were collected at U.S. Geological Survey (USGS) station number 385626107212000 by following data collection procedures and protocols in Edwards and Glysson (1999). The samples were freeze-dried a