Which river drains Lake Tahoe?

The Truckee River drains Lake Tahoe. It is the lake’s only surface outlet, leaving from Tahoe City on the northwest shore and flowing northeast through California and Nevada.

The river runs about 121 miles before emptying into Pyramid Lake, an endorheic lake in Nevada’s Great Basin. Unlike the Truckee, Pyramid Lake has no outlet to the sea, so the basin is closed and loses water mainly through evaporation.

The other choices are nearby Great Basin rivers, but they do not drain Lake Tahoe. The Carson River receives some Truckee water through the Derby Diversion, which can cause confusion; that is a human-made transfer, not Tahoe’s natural outlet. The river is also important for Reno-area water supplies, irrigation, recreation and the endangered cui-ui fish of Pyramid Lake.