Groundwater Monitoring

Groundwater monitoring activities are funded by an Aquifer Protection Area (APA) fee. This is a voter-approved fee which goes toward many projects and initiatives that protect the Spokane Valley-Rathdrum Prairie Aquifer - the same aquifer that supplies drinking water to most residents in the greater Spokane area. This fee is anticipated to come up for renewal in the next few years. For more information about the fee, please visit the APA page.
The Spokane Valley Rathdrum Prairie Aquifer (SVRP Aquifer) is the sole source of water for over 600,000 people in Spokane County, WA and Kootenai County ID, this underground water-bearing rock formation is one of the region's most important resources. The aquifer is unique both for its fast flowing and generous water supply, and for its high susceptibility to contamination.

Since 1977, Spokane County has been monitoring water quality conditions in the aquifer. Currently, Water Resources staff collect samples on a quarterly basis from 29 monitoring wells and 16 public supply wells. Objectives of the groundwater monitoring program include:
  • Establish the areal distribution of groundwater quality from a network of wells covering the Spokane Valley-Rathdrum Prairie Aquifer recharge area
  • Identify water quality impacts from activities on the land surface
  • Evaluate the potential water quality impacts of aquifer discharge on river quality
  • Collect long-term data from wells to establish water quality and quantity trends

SVRP Aquifer Water Level Trends

SVRP 1999-2015 Water Level Data