And that's why they call it a flood plain! This flood plain is located along Gristmill Trail and the Far Mill River in Shelton. Every year there is a flood or two, but not always this big. See the blaze on the tree above marking the trail location?
There was quite a current in the river today. The Far Mill River drops in elevation pretty rapidly, which is why so many mills were located alongside the river. That gives it a strong current. Kayakers also enjoy the current, and are seen putting in at this spot during floods.
This river is only for very experienced kayakers, however. In addition to some falls, there are large standing waves like the one above, caused by rocks below the surface.