Hydrology of area 58, northern Great Plains and Rocky Mountain coal provinces, Colorado and Utah

Abstract

Hydrologic information and analyses are needed to aid in decisions to lease Federally owned coal and to prepare the necessary environmental assessments and impact-study reports. This need has become even more critical with the enactment of the Surface Mining Control and Reclamation Act of 1977. This report, which is one of a series covering the Nation's coal areas, presents information thematically by describing single hydrologic topics through the use of brief texts and accompanying maps, graphs, or other illustrations. The topics encompass the complete physical and hydrologic setting of the area. Area 58, located primarily in west-central Colorado, is in the Southern Rocky Mountain and Colorado Plateau physiographic provinces. The area consists of 13,132 square miles of diverse geology, topography, and climate. The diversity results in a broad array of hydrologic characteristics. The Colorado River is the principal river draining the region. The headwaters of the Colorado and most of its tributaries originate in the mountains forming the eastern boundary of the area. This boundary also is the Continental Divide. The U.S. Geological Survey operates a network of hydrologic stations to measure the streamflow and waterquality conditions. This network currently includes 97 stations collecting streamflow data and 12 stations collecting water-quality data. Information is available for many surface-and groundwater sites measured in the past. Data available include rate of flow, water levels, and water quality. These data are available from the U.S. Geological Survey either in published reports or from computer storage through the National Water-Data Exchange (NAWDEX) or the National Water-Data Storage and Retrieval System (WATSTORE). All coal mines in the basin but one are underground. Production from these mines during 1982 totaled almost 1.0 INTRODUCTION 7.7 Objective Report Summarizes Available Hydrologic Data Existing hydrologic conditions and sources of information are identified to aid leasing decisions and preparation and appraisal of environmental impact studies and mine-permit applications. Hydrologic information and analysis are needed to aid in decisions to lease Federally owned coal and to prepare the necessary environmental assessments and impact study reports. This need has become even more critical with the enactment of Public Law 95-87, the "Surface Mining Control and Reclamation Act of 1977." This Act requires an appropriate regulatory agency to issue mining permits based on the review of permit application data to assess hydrologic impacts. This need is partly fulfilled by this report, which broadly characterizes the hydrology of Area 58 in west central Colorado and eastern Utah, a part of the Northern Great Plains, and Rocky Mountain Coal Provinces (fig. 1.1-1). This report is one of a series that describes coal provinces nationwide. MONTROSE

Historical perspective of statewide streamflows during the 2002 and 1977 droughts in Colorado

“…These transmountain diversions primarily are associated with the Denver Water Board, the Colorado-Big Thompson Project, the Fryingpan-Arkansas Project, and several other smaller entities. During a 10-year period (1973-82), these diversions exported an average of about 509,000 acre-ft/yr from the western slope of the Continental Divide to the eastern slope (Chaney and others, 1987). Because of the structure of water rights in Colorado, the majority of these transmountain diversions take place during the snowmelt period.…”

Environmental Setting and Implications on Water Quality, Upper Colorado River Basin, Colorado and Utah

“…Although the magnitude of these floods can be quite large, exceptionally large snowmelt floods that could cause severe flooding are very uncommon. Because of the annual nature of snowmelt floods, most stream channels are capable of carrying these snowmelt floods without extensive bank overflow or substantial flooding (Chaney and others, 1987). Reservoir storage, interbasin water transfers, and local diversions for irrigation also diminish the magnitude of the annual snowmelt floods.…”

“…In the eastern part of the study unit, the flow system primarily involves recharge in the mountainous areas and discharge in the lower valleys. Recharge in the western part of the basin is due to precipitation in the form of snow or rain and discharge occurs in the valleys (Chaney and others, 1987). Most ground water is discharged into streams through seeps along the side or bottom of the stream channel or to the land surface by springs.…”

Using tracers to evaluate streamflow gain-loss characteristics of Terror Creek, in the vicinity of a mine-permit area, Delta County, Colorado, water year 2003

“…Underground coal mining has been active in the North Fork Gunnison River area since about 1900. The Bowie mine has been active in the area between Hubbard and Terror Creeks since about 1952 (Chaney and others, 1987). Mine operators anticipate increasing mining activity to the western part of the mine-permit area, including the area directly beneath the surface of Terror Creek (J.E.…”