The object of Phase 2 is the same as Phase 1, to increase stream flow over a dry riffle.

At this point, the Lemhi spreads out over a gravel bar. Water depth is reduced to mere inches. The solution is an in-stream diversion dam to concentrate water flow for fish migration.

The river is far too shallow to allow passage for a full grown salmon, and an immediate short-term solution to this problem is to restrict the width of the channel.