A couple of weeks ago, I headed up north to Hancock County, IA to find the headwaters of the Boone River. After studying this aerial, I was able to locate these agricultural fields that had been tiled and drained for farming. This is where the Boone River originates.
aerial of the west and east channels emptying into the main channel of the Boone River
west and east channels drain into the main channel of the Boone River....channelization, 8-ft culverts, and corn as far as the eye can see (looking north)
Contrast the above images with these below. This is the mouth of the Boone River, 85 miles to the south, at the confluence with the Des Moines River. This site is magnificent on so many levels....the old channels, the braiding, the deposition and erosion, the sandbars, the floodplain, the river banks, the soils and vegetation, and of course, the power in the movement of water.
Google aerial at the confluence