Publications

Pueblo Reservoir is one of southeastern Colorado's most valuable water resources. The reservoir provides irrigation, municipal, and industrial water to various entities throughout the region. The reservoir also provides flood control, recreational activities, sport fishing, and wildlife enhancement to the region. The Bureau of Reclamation is working to meet its goal to issue a Final...

Ground- and surface-water samples were collected in the vicinity of the Standard Mine in west-central Colorado in order to characterize the local ground-water flow system, determine metal concentrations in local ground water, and better understand factors controlling the discharge of metal-rich waters from the mine. The sampling program included a one-time sampling of springs, mine adits...

The population of Delta County, Colorado, like that in much of the Western United States, is forecast to increase substantially in the next few decades. A substantial portion of the increased population likely will reside in rural subdivisions and use residential wells for domestic water supplies. In Colorado, a subdivision developer is required to submit a water-supply plan through the...

Data were collected and experiments were conducted from 2003 to 2006 by the U.S. Geological Survey, in cooperation with the Bureau of Land Management, to support research into understanding processes that liberate, disperse, and concentrate erosion byproducts in Mancos Shale landscapes. The study area was the Gunnison Gorge National Conservation Area near Montrose and Delta, Colorado...

The primary purpose of the study described in this report was to determine if the fungicide chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile), three of its transformation products, or selected other pesticides are transported to surface water after use on peanuts or other crops in Texas and Oklahoma. The results summarized here are part of a larger study that includes data from sites...

In 1974, the Colorado River Basin Salinity Control Act was passed into law. This law was enacted to address concerns regarding the salinity content of the Colorado River. The law authorized various construction projects in selected areas or "units" of the Colorado River Basin intended to reduce the salinity load in the Colorado River. One such area was the Grand Valley Salinity Control...

Elevated selenium concentrations in streams are a water-quality concern in western Colorado. The U.S. Geologic Survey, in cooperation with the Colorado Department of Public Health and Environment, summarized selenium loading in the Lower Gunnison River Basin to support the development of total maximum daily selenium loads at sites that represent the cumulative contribution to U.S...

Declining fish health, fish exhibiting external lesions, incidences of intersex, and death, have been observed recently within the Potomac River basin. The basin receives surface runoff and direct inputs from agricultural, industrial, and other human activities. Two locations on the North Fork of the Shenandoah River were selected for study in an attempt to identify chemicals that may...

Following a wildfire, such as the 2002 Missionary Ridge fire, a number of hydrologic hazards may develop that can have an important impact on water resources, businesses, homes, reservoirs, roads, and utilities in the wildland urban interface (areas where homes and commercial developments are interspersed with wildlands) in mountainous areas of the Western United States. This fact sheet...

The Pine River Watershed Stakeholders Group was created in December 1997 to allow local participation in addressing water-quality issues in Los Pi?os River watershed, including Vallecito Reservoir in southwestern Colorado. One water-quality issue identified by the stakeholder group is to increase the understanding of the current water quality of Vallecito Reservoir, its two major inflows...

The lower South Platte River basin of Colorado and Nebraska is an area of intense agriculture supported by surface-water diversions from the river and ground-water pumping from a valley-fill alluvial aquifer. Two well networks consisting of 45 wells installed in the South Platte alluvial aquifer were sampled in the early 1990s and again in the early 2000s to examine near-decadal ground...

Changes in stream chemistry were studied for 4 years following large wildfires that burned in Glacier National Park during the summer of 2003. Burned and unburned drainages were monitored from December 2003 through August 2007 for streamflow, major constituents, nutrients, and suspended sediment following the fires. Stream-water nitrate concentrations showed the greatest response to fire