The Truckee River is a beautiful stretch of water draining lake Tahoe of it's water and tourists of their money. One warm weekends, you could probably walk raft-to-raft the entire stretch and never get your feet wet.
This path follows the river from Truckee all the way to Squaw Valley, though many people turn around at the intersection with Alpine Meadows and the River Run restaurant. It's easy, beautiful, and suitable for all abilities. It's crowded, so don't go too fast or get too distracted by the bikinis... I mean rafters.
Unlike some of the other paved paths around Lake Tahoe, this one rarely crosses a road and is far enough from the highway that you are mostly captivated by the river.