Water-quality data for streams in the Upper North Fork of the Gunnison River, Colorado

Abstract

Coal mining in the upper reaches of the North Fork of the Gunnison River has been a major economic factor in the area for many years. In recent years, concerns about impacts of coal mining on surface-water quality have been raised. To answer such questions, it was necessary to describe the areas natural or background surface-water quality. To achieve this description for the study area, a program for the synoptic collection of water-quality data was established in 1982.Water-quality data was collected on continously flowing streams in the Upper North Fork of the Gunnison River basin in 1982 and 1983. Each site was sampled repetitively as changes occurred in discharge and specific conductance.The water-quality sites in the study area were established in March 1982 and were selected on the basis of differences in geology, land use, and climate. Sites that were sampled in this study are shown in figure 1.Several samples were taken at each site to represent different streamflow and specific-conductance values. Some sites were inaccessible during much of the spring season; therefore, some higher streamflows from snowmelt may not be represented.Onsite measurements of specific conductance, water temperature, pH, and streamflow were recorded for each sample. Analyses and calculations were performed to determine concentrations of major dissolved constituents, nutrients, trace elements, suspended sediment, and water properties. Water sample analyses were performed at the U.S. Geological Survey's Denver Central Laboratory. The trace elements were analyzed for total, dissolved, and suspended concentrations.Onsite measurements and data for the major dissolved constituents collected at sites in this study are shown in tables 2-38 in the "Water-Quality Data" section. Data for nutrients and trace elements from samples collected at these sites are shown in tables 39-75 in the "Water-Quality Data" section.These data are also in the U.S. Geological Survey's National Water Storage and Retrieval System (WATSTORE). In addition, a statistical summary of water-quality data collected at two streamflow-gaging stations prior to the start of this study are in tables 76 and 77. These stations have data from the analyses of enumerable water-quality samples; therefore, only a summary of the data is presented, which includes the number of samples, mean, range, and standard deviation, for each constituent. The data are also available from the U.S. Geological Survey's WATSTORE system. WATER-QUALITY DATAThe following abbreviations are used in tables 2-77.

Effects of a landslide complex on sediment discharges and loads in the Muddy Creek drainage basin and deposition into Paonia Reservoir, west-central Colorado, 1986-87

“…Greater than average precipitation for several consecutive years probably saturated the landslide complex, which increased the pore-water pressure within the complex and enabled the complex to move more easily. (Norris and Maura, 1985). Several streamflow-gaging stations have been operated by the U.S. Geological Survey within the study area; however, none of these stations has been in operation Personnel of the Colorado Geological Survey surveyed profiles of the landslide complex in August 1985, before the greatest movement of the complex in 1986, and again in May and June 1986, after movement of the complex.…”

Summary of the U.S. Geological Survey and U.S. Bureau of Land Management national coal-hydrology program, 1974-84

“…The results of a study undertaken in the drainage basin of the North Fork Gunnison River to determine the regional waterresources system in the area of the Somerset coal field in Gunnison County, Colorado, in coal area 58 is in a report by Norris (1987). A summary of water-quality data collected in streams in the North Fork Gunnison River in Colorado is reported by Norris and Maura (1985).…”