At this moment the Chagrin Flow is at 58 CFS. That is a pretty low flow. The areas that hold fish during low flow times will be the deep holes. They may not be very apparent to the naked eye. As the fall rain comes, the flow of the rivers will begin comming up, and those dry land areas you see will be covered with water.
When I say deep holes, they may only be 3' deep, but that is a deep hole compared to the rest of the water you are looking at. When the flows of the rivers come up, that hole goes from 3' to 5' or greater.
Depending on the species of fish you are looking to catch, will determine where you would want to begin looking for them. With the heat of the summer, most fish are gonna be looking for shade, so if you find the areas of the stream with overhanging trees this would be a good place to start. Also look for those downed trees in the river.
As the water flows next to these downed trees, the current undercuts the tree and digs a deeper hole into the stream bed. Alot of fish like to sit in and around those deep cuts.