The Grande Ronde Aquifer is part of the regional Columbia Basin basalt aquifer system and is one of three aquifer systems that make up the Water Resource Inventory Area (WRIA) 32 along with the Wanapum and Saddle Mountain aquifers. The Grand Ronde Aquifer is the main source of drinking water for Pullman, Washington and Moscow, Idaho. For several decades the water levels in the Grande Ronde Aquifer have been in decline – up to 3 feet per year – due to pumping by the cities and universities.
References
Grande Ronde Aquifer Wikipedia(Text) CC BY-SA