Groundwater

The conversion of agricultural land to urban residential land is associated with rapid population growth in the Grand Valley of western Colorado. Information regarding the effects of this land-use conversion on deep percolation, irrigation-water application, and associated salt loading to the Colorado River is needed to support water-resource planning and conservation efforts.

More than 70 percent of the municipal water supply in the south Denver metropolitan area is provided by groundwater, and homeowners in rural areas depend solely on self-supplied groundwater for water supply. Increased groundwater withdrawal to meet the demand of the rapidly growing population is causing water levels to decline. The U.S. Geological Survey, in cooperation with the Rural Water...

As part of the National Water Quality Assessment Program (NAWQA), the USGS has evaluated ground-water quality in the High Plains aquifer system. Beginning in 1999 and continuing for a period of 6 years, the High Plains Regional Groundwater Study intensively investigated the quality of groundwater resources within the study area. Water quality impairment coupled with water-level declines focus...

The Denver Basin aquifer system is a critical water resource for growing municipal, industrial, and domestic uses along the semiarid Front Range urban corridor of Colorado. The confined bedrock aquifer system is located along the eastern edge of the Rocky Mountain Front Range where the mountains meet the Great Plains physiographic province. Mining, transportation, agricultural, and urban...

The South Platte River valley between the City of Brighton in Adams County and the town of Fort Lupton in Weld County, Colorado, contains many wetland areas that provide habitat for wildlife in the Front Range Urban Corridor. The extent of aggregate mining along this reach of the South Platte River valley continues to increase as the demand for aggregate grows in response to urban development. The...

The South Platte Decision Support System (SPDSS) is a data base system being developed by the Colorado Water Conservation Board (CWCB) to provide water users, managers, and State of Colorado agencies access to important information related to water management issues affecting the South Platte River system.

In the mid-1990s, the Colorado Division of Water Resources (CDWR) adopted rules governing measurement of tributary groundwater pumpage for the Arkansas River Basin. The rules allowed groundwater pumpage to be determined using one of two approaches—power conversion coefficient (PCC) or totalizing flowmeters (TFM). In addition, the rules allowed a PCC to be applied to the electrical power usage up...

Population growth near Buena Vista and Salida in Chaffee County has caused concern for the long-term availability and quality of groundwater . Groundwater withdrawals from deep wells that are completed in the basin-fill deposits and designed to supply multiple-dwelling developments could cause drawdowns in water levels of the overlying aquifers. Continued development of groundwater supplies in...

The Great Sand Dunes National Monument is located in south-central Colorado along the eastern edge of the San Luis Valley. The predominant feature in the Monument is the 39 square-mile sand dune field which rises up to 750 feet above the valley floor. The dune field is a young geologic feature; U.S. Geological scientists estimate that the dunes are between 2,000 and 12,000 years old. The...

The South Platte River Basin study, conducted as part of the U.S. Geological Survey's National Water-Quality Assessment Program, combines information on water chemistry, physical characteristics, stream habitat, and aquatic life to provide science-based insights for current and emerging water issues in surface waters (streams, rivers, reservoirs) and groundwaters of the South Platte River Basin...

The USGS has assessed the effects of increasing urbanization on ground- and surface-water resources in the Fraser River watershed. The population of Grand County increased 93 percent between the years of 1970 and 1990. The majority of the new development in the watershed will rely on ground water and individual septic disposal systems (ISDS's). This study has assessed the potential effects of ISDS...

MODFLOW is the USGS's modular hydrologic model. MODFLOW is considered an international standard for simulating and predicting groundwater conditions and groundwater/surface-water interactions. Originally developed and released solely as a groundwater-flow simulation code when first published in 1984, MODFLOW's modular structure has provided a robust framework for integration of additional...