The Mountain Home Plateau Aquifer, extending westward across southern Elmore County into Ada County, provides municipal supply to the City of Mountain Home and Mountain Home Air Force Base, along with irrigation, commercial, domestic and industrial supplies to farms, dairies, and other businesses in Elmore County.
In addition to groundwater from the aquifer, other water supplies on the Mountain Home Plateau are Snake River water pumped for irrigation of farms, Little Camas Reservoir water conveyed to the area by the Mountain Home Irrigation District from the South Fork Boise River watershed, and water from creeks that flow onto the Plateau from the Danskin Mountains and Bennett Hills.
Snake River at CJ Strike Reservoir
Groundwater levels in the Mountain Home Plateau Aquifer have been declining in portions of the County for more than 40 years, prompting declaration of the Cinder Cone Butte Critical Groundwater Area in 1981 and the Mountain Home Ground Water Management Area in 1982.
The water table has fallen 100 feet or more in some locations. The decline in aquifer water levels threatens the existing economy and for many years has been a severe constraint on economic growth. Without some sort of action, wells will continue to go dry and existing water uses will be curtailed.
Management and administration of groundwater on the Mountain Home Plateau is influenced by four designated areas.
There have been a number of investigations and published reports of groundwater conditions within Elmore County.
South Fork Boise River
Anderson Ranch Reservoir