Shenandoah National Park, located along the crest of the Blue Ridge Mountains in Virginia, is the origin of the headwaters of three river drainages; the Shenandoah River to the west and the Rappahannock and James Rivers to the east. There are 42 watershed basins on the west side of Shenandoah and 28 watershed basins on the east, combining for a total of about 90 small streams. A chief feature of these high elevation streams is high gradient, with pools interspersed with riffles, rapids, cascades and falls, and bottoms chiefly of large gravel, rubble, boulder, and bedrock. In many places, streams drop over ledges, creating waterfalls up to 28m high. Most streams are heavily shaded and cool or even cold in the summer, and are typically clear with rain-caused turbidity quickly disappearing.