Abstract
The Clark Fork and Kootenai River basins lie within the Northern Intermontane Basin physiographic province. The intermontane basins are structurally downdropped relative to the surrounding mountains and filled with basin-fill deposits. Groundwater occurs within the unconsolidated to poorly consolidated Tertiary and Quaternary basin-fill deposits, and to a lesser extent in the fractured bedrock in the surrounding mountains. More than 70,000 wells within the Clark Fork/Kootenai River basins withdraw water from aquifers found in unconsolidated to poorly consolidated deposits and surrounding fractured bedrock. Most wells (92 percent) provide water for domestic purposes, but account for only 9 percent of annual groundwater withdrawals; irrigation, public water supply, and industrial wells—only about 8 percent of wells—account for 90 percent of withdrawals.
Start Date
24-4-2015 11:00 AM
End Date
24-4-2015 11:30 AM
Document Type
Presentation
Groundwater Conditions and Use in the Clark Fork and Kootenai River Basins
The Clark Fork and Kootenai River basins lie within the Northern Intermontane Basin physiographic province. The intermontane basins are structurally downdropped relative to the surrounding mountains and filled with basin-fill deposits. Groundwater occurs within the unconsolidated to poorly consolidated Tertiary and Quaternary basin-fill deposits, and to a lesser extent in the fractured bedrock in the surrounding mountains. More than 70,000 wells within the Clark Fork/Kootenai River basins withdraw water from aquifers found in unconsolidated to poorly consolidated deposits and surrounding fractured bedrock. Most wells (92 percent) provide water for domestic purposes, but account for only 9 percent of annual groundwater withdrawals; irrigation, public water supply, and industrial wells—only about 8 percent of wells—account for 90 percent of withdrawals.