The tailout:  Within the anatomy of trout streams, there is a section of water--- a flow, known as the tailout.  Typically this is found at the end of a pool.  Often it is shallow due to rocks and gravel that have settled here, and typically the current's speed gathers intensity as it passes through, onward to faster water downstream. 

One such tailout often gathering anglers' attention, and offering safe passage to Chimney Hole downriver, is the tailout of the Trestle Flat on Esopus Creek.

Tailout, 11x14 (DtC):