Rathdrum Prairie

The floods left something more useful than a corridor. The gravels, cobbles and boulders they dumped here hold the Spokane Valley-Rathdrum Prairie Aquifer, more than 800 feet thick in places under the northern prairie, which supplies drinking water to more than half a million people in Kootenai County and around Spokane. In 1978 it became the second aquifer the Environmental Protection Agency designated a sole source aquifer. The same open gravels that make it so productive leave it with no protective layer, so what spills on the prairie can reach the water below.

Where it stands

Worth the stop nearby

• Trail of the Coeur d'Alenes — 24 mi
  Seventy-two paved miles laid over a railbed poisoned by a century of ore trains.
• Farragut State Park — 25 mi
  The Navy built its second-largest boot camp 375 miles from the ocean, and still tests submarines on the lake.

More markers nearby

• Treaty Rock (q'emiln) — 4.2 mi
• Coeur d'Alene Lake — 20 mi
• Restoring the Lake — 20 mi
• Pen d'Oreille City — 22 mi