There is a Navy submarine base in Idaho. Not a recruiting office — an actual submarine test range. At Bayview, on the shore of Lake Pend Oreille, the Naval Surface Warfare Center's Acoustic Research Detachment has been quietly testing submarine and ship designs for decades.
The lake is the whole point. At 1,150 feet deep, Lake Pend Oreille is Idaho's largest, deepest, and quietest body of water, according to the Navy. The rivers and inlets all feed the north end, so the south end sits like a laboratory: nearly still, flat-bottomed, and cold below 100 feet — a free-field, ocean-like environment without the problems and costs of open-ocean operations.
The detachment's star is the Cutthroat, the Large Scale Vehicle 2 and the world's largest unmanned submarine. It evaluates the acoustic performance of large-scale submarine and surface ship models — hull shaping, acoustic dampening, propulsors, sonar systems. Networks of extremely sensitive hydrophones listen from the lake bottom, devices so keen they can pick up rain falling on the surface.
The work done in these waters has supported nearly every major American submarine design of the last six decades. The Virginia class — which includes the USS Idaho (SSN-799), the submarine bearing the state's name — descends from the quiet-ship research refined on this very lake.
The 25-acre detachment sits beside Farragut State Park, on the same shoreline where a different navy once trained 293,000 sailors. The uniforms changed; the mission became silence itself.
The site director has described the lake's south end as an almost laboratory-static environment 1,100 feet deep, with a flat bottom and constant cold below 100 feet that makes the mathematical analysis clean. The Navy has run model-submarine research on this lake since 1967 — a quiet, landlocked mission that keeps American submarines the quietest in the world.