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Spokane Valley-Rathdrum Prairie Aquifer Protection District Protecting Our Priceless Water Supply

This story was written by the Our Gem Collaborative team for the CDA Press on Sunday, April 4, 2021. Read the original article.

The Spokane Valley-Rathdrum Prairie (SVRP) aquifer covers about 370 square miles in northern Idaho and eastern Washington. It is composed of ice age flood deposited gravels, cobbles, and boulders and is filled with water. The SVRP aquifer is considered unconfined, meaning it has no protective layer of clay or rock above it to keep out pollutants that are spilled on the ground surface. In fact, our geology is so porous that Hauser and Rathdrum Creeks flow only a short distance before soaking into the aquifer.

The aquifer water is not stagnant however, an elevation change of nearly 600 feet from the northern Rathdrum Prairie to Lake Spokane keeps aquifer water flowing underground south and west to Coeur d’Alene, Post Falls, and into Washington. Because of the permeable nature of the aquifer, groundwater flow velocities can reach approximately 50 feet per day. Along this route, there are multiple large interchanges of water with the Spokane River. Since Spokane River water comes directly from Coeur d’ Alene Lake, protecting Lake water quality also protects the quality of the vast reservoir of drinking water in our aquifer.

The Kootenai County Aquifer Protection District (APD) Budget and Policy Board was approved by voters and established by the Board of County Commissioners in 2007 for the protection of the groundwater quality in the Rathdrum Prairie aquifer. The APD Board is singularly concerned with protecting the aquifer from contamination and depletion. They determine how funding should be spent, they encourage cooperative efforts among relevant agencies, and they develop an annual budget and funding requests for the District. There can be up to 11 Board members, nine of which must meet specific criteria. Current APD Board membership can be found at

Funding for the District comes from a fee for every “parcel” of land in Kootenai County that is within the aquifer boundary. By statute, the fee can range from $5.50 to $12.50 per parcel, per year, and is collected with property taxes. The APD parcel fee has never been more than $8.

Aquifer Protection District funding is typically used for:

  1. Department of Environmental Quality well testing throughout Kootenai County’s aquifer boundaries. This process monitors water quality trends and checks for deterioration in aquifer quality.
  2. Panhandle Health District for their Critical Materials Program that monitors businesses that handle or store large volumes of hazardous liquids that could leak into our aquifer. Panhandle Health District staff do an excellent job educating and assisting those businesses in meeting requirements.
  3. The Confluence Project, a yearlong high school science project focused on critical thinking skills and hands-on expert guided study of groundwater, snowpack and surface water. Student research is highlighted each spring at the Youth Water Summit that attracts about 500 student presenters.
  4. The Spokane River Forum, a bistate annual scientific conference bringing together agencies and organizations devoted to maintaining water quality and quantity in the Spokane River. The forum enables broad sharing of research results and cooperative efforts to preserve and enhance water quality.
  5. Production of the Aquifer Atlas to educate the entire region about the formation, history, function and vulnerability of this incredible water supply. The Atlas is available at your local library, in schools, at Department of Environmental Quality and Panhandle Health District offices and your local Chamber of Commerce. The Atlas is updated every few years with the next edition slated for 2021.

University of Idaho

Physical Address:
1031 N. Academic Way,
Suite 242
Coeur d'Alene, ID 83814

Phone: 208-667-2588

Fax: 208-664-1272



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