The movement of gravel east started when the rip rap fingers were put in to protect the old highway bridge. The river had slowly eroding the West bank so action was taken to protect the bridge foundations. It did just that by moving the gravel East over time. Prior to that the river was a straight shot from the sandstone toe ( above the bridges ) under the bridges to the old gravel bar down stream. The recent movement that took out several acres of the East bank above the bridges in a flood has returned back to more or less the normal track. The gravel build up at the launch is not going anywhere as long as the gravel flow is directed to the East side of the river.

When I was a kid you had a small gravel bar upstream of the old bridge and the water where we went swimming just down from the nursery was 4 ft deep on the East side of the river. The river from the sandstone toe down above the old highway bridge to W's bar was a long deep stretch with the West side being very deep and we used the railroad bridge to jump off of and never hit bottom. By changing the hydrology at the bridges it simply allowed for the river gravel to build up. Best way to think of it is from the sandstone toe above the bridges the river was like a hose cleaning out things until the flows lost that effect and the gravel built up at W's bar. Loose the fire hose effect and gravel builds up.