Spillway

This is the spot where the Cher River splits around the island at Saint-Aignan. The south channel flows toward the bridge a little further downriver where a small dam slows the river's flow. Here, the more shallow north channel begins where the river is held back by a spillway. In dry times, the top of the spillway is exposed and the north channel is reduced to a trickle. In times of heavy rains upstream, the spillway is completely submerged as the north channel fills up.

Looking upriver from the spillway at the eastern end of the island.

When I took this photo, the river's flow was more or less normal. The bridge dam and the spillway force the river to back up for several kilometers upstream, creating a small reservoir called the Three Provinces Lake to the east. There is a campground on the south shore and a sand quarry on the northern side. The now defunct Canal de Berry begins at the lake and parallels the river eastward toward Vierzon, then connects to another canal parallel to the Loire, for a length of over 260 kilometers. The canal operated from 1840 until it was closed in 1955. A local association is working to re-open the canal for recreational use and, according to Wikipedia, there are currently 17 kilometers open to public navigation.