Here is a collection of photos from four of the photo points along the South Fork Boise River. Photos from November 24, 2018.
The above photo is from the bracket on the sfboise#17 sign. This site is just downstream of the boat ramp, about a mile downstream of Anderson Ranch Dam.
The quiescent pool in the South Fork is formed from the debris slide from September 12, 2013 that temporarily blocked the river flow as very large boulders tumbled into the river from the landslide. In the past five years much of the material have moved downstream except for the largest boulders that still form a rapid and back up water to form this pool.