A large scale renovation of the River Wensum in Norfolk is underway by the Environment Agency and Natural England.
The biggest river restoration project in Europe will see its banks realigned and the river re-routed.
The project is a response to the poor ecology seen in the river compared to national and European levels.
"We're trying to create diversity of flow so we have slow sections that some wildlife like and faster sections," said project manager John Abraham.
The river has been criticised for being dug too deep, wide and straight causing habitats and species to be lost.