Rathdrum, Idaho — Town Sitting on an Underground River of Gravel

Rathdrum was once the county seat of a Kootenai County that covered much of the Idaho Panhandle.

Railroads helped establish the town in the 1880s, and the surrounding prairie became productive agricultural country.

Then Coeur d'Alene grew. Voters moved the county seat there in 1908.

Rathdrum's more important regional asset turned out to be underground.

The Spokane Valley–Rathdrum Prairie Aquifer lies beneath thick deposits of coarse gravel left by glacial and Ice Age flood processes. Water moves rapidly through those sediments and supplies drinking water to hundreds of thousands of people across northern Idaho and eastern Washington.

It is not a giant underground lake. Think of an enormous saturated pile of gravel.

Modern growth has covered more of the prairie with homes and businesses, making protection of that invisible water supply increasingly important.

Rathdrum lost the courthouse. It kept something much larger underneath it.